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author | root <root@lamia.panaceas.james.local> | 2015-12-19 13:13:57 +0000 |
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committer | root <root@lamia.panaceas.james.local> | 2015-12-19 14:18:03 +0000 |
commit | 1a2238d1bddc823df06f67312d96ccf9de2893cc (patch) | |
tree | c58a3944d674a667f133ea5a730f5037e57d3d2e /uclibc-crosstools-gcc-4.4.2-1/usr/share/info | |
download | bootloader-1a2238d1bddc823df06f67312d96ccf9de2893cc.tar.gz bootloader-1a2238d1bddc823df06f67312d96ccf9de2893cc.tar.bz2 bootloader-1a2238d1bddc823df06f67312d96ccf9de2893cc.zip |
CFE from danitool [without hostTools dir]: https://mega.nz/#!mwZyFK7a!CPT3BKC8dEw29kubtdYxhB91G9vIIismTkgzQ3iUy3k
Diffstat (limited to 'uclibc-crosstools-gcc-4.4.2-1/usr/share/info')
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-rw-r--r-- | uclibc-crosstools-gcc-4.4.2-1/usr/share/info/bfd.info | 11288 | ||||
-rw-r--r-- | uclibc-crosstools-gcc-4.4.2-1/usr/share/info/binutils.info | 4493 | ||||
-rw-r--r-- | uclibc-crosstools-gcc-4.4.2-1/usr/share/info/configure.info | 2773 | ||||
-rw-r--r-- | uclibc-crosstools-gcc-4.4.2-1/usr/share/info/dir | 43 | ||||
-rw-r--r-- | uclibc-crosstools-gcc-4.4.2-1/usr/share/info/gprof.info | 2469 | ||||
-rw-r--r-- | uclibc-crosstools-gcc-4.4.2-1/usr/share/info/ld.info | 7611 | ||||
-rw-r--r-- | uclibc-crosstools-gcc-4.4.2-1/usr/share/info/standards.info | 5576 |
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diff --git a/uclibc-crosstools-gcc-4.4.2-1/usr/share/info/as.info b/uclibc-crosstools-gcc-4.4.2-1/usr/share/info/as.info new file mode 100644 index 0000000..a8d3810 --- /dev/null +++ b/uclibc-crosstools-gcc-4.4.2-1/usr/share/info/as.info @@ -0,0 +1,22073 @@ +This is as.info, produced by makeinfo version 4.8 from as.texinfo. + +START-INFO-DIR-ENTRY +* As: (as). The GNU assembler. +* Gas: (as). The GNU assembler. +END-INFO-DIR-ENTRY + + This file documents the GNU Assembler "as". + + Copyright (C) 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000, 2001, 2002, +2006, 2007, 2008, 2009 Free Software Foundation, Inc. + + Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation; with no +Invariant Sections, with no Front-Cover Texts, and with no Back-Cover +Texts. A copy of the license is included in the section entitled "GNU +Free Documentation License". + + +File: as.info, Node: Top, Next: Overview, Up: (dir) + +Using as +******** + +This file is a user guide to the GNU assembler `as' (GNU Binutils) +version 2.20. + + This document is distributed under the terms of the GNU Free +Documentation License. A copy of the license is included in the +section entitled "GNU Free Documentation License". + +* Menu: + +* Overview:: Overview +* Invoking:: Command-Line Options +* Syntax:: Syntax +* Sections:: Sections and Relocation +* Symbols:: Symbols +* Expressions:: Expressions +* Pseudo Ops:: Assembler Directives + +* Object Attributes:: Object Attributes +* Machine Dependencies:: Machine Dependent Features +* Reporting Bugs:: Reporting Bugs +* Acknowledgements:: Who Did What +* GNU Free Documentation License:: GNU Free Documentation License +* AS Index:: AS Index + + +File: as.info, Node: Overview, Next: Invoking, Prev: Top, Up: Top + +1 Overview +********** + +Here is a brief summary of how to invoke `as'. For details, see *Note +Command-Line Options: Invoking. + + as [-a[cdghlns][=FILE]] [-alternate] [-D] + [-debug-prefix-map OLD=NEW] + [-defsym SYM=VAL] [-f] [-g] [-gstabs] + [-gstabs+] [-gdwarf-2] [-help] [-I DIR] [-J] + [-K] [-L] [-listing-lhs-width=NUM] + [-listing-lhs-width2=NUM] [-listing-rhs-width=NUM] + [-listing-cont-lines=NUM] [-keep-locals] [-o + OBJFILE] [-R] [-reduce-memory-overheads] [-statistics] + [-v] [-version] [-version] [-W] [-warn] + [-fatal-warnings] [-w] [-x] [-Z] [@FILE] + [-target-help] [TARGET-OPTIONS] + [-|FILES ...] + + _Target Alpha options:_ + [-mCPU] + [-mdebug | -no-mdebug] + [-replace | -noreplace] + [-relax] [-g] [-GSIZE] + [-F] [-32addr] + + _Target ARC options:_ + [-marc[5|6|7|8]] + [-EB|-EL] + + _Target ARM options:_ + [-mcpu=PROCESSOR[+EXTENSION...]] + [-march=ARCHITECTURE[+EXTENSION...]] + [-mfpu=FLOATING-POINT-FORMAT] + [-mfloat-abi=ABI] + [-meabi=VER] + [-mthumb] + [-EB|-EL] + [-mapcs-32|-mapcs-26|-mapcs-float| + -mapcs-reentrant] + [-mthumb-interwork] [-k] + + _Target CRIS options:_ + [-underscore | -no-underscore] + [-pic] [-N] + [-emulation=criself | -emulation=crisaout] + [-march=v0_v10 | -march=v10 | -march=v32 | -march=common_v10_v32] + + _Target D10V options:_ + [-O] + + _Target D30V options:_ + [-O|-n|-N] + + _Target H8/300 options:_ + [-h-tick-hex] + + _Target i386 options:_ + [-32|-64] [-n] + [-march=CPU[+EXTENSION...]] [-mtune=CPU] + + _Target i960 options:_ + [-ACA|-ACA_A|-ACB|-ACC|-AKA|-AKB| + -AKC|-AMC] + [-b] [-no-relax] + + _Target IA-64 options:_ + [-mconstant-gp|-mauto-pic] + [-milp32|-milp64|-mlp64|-mp64] + [-mle|mbe] + [-mtune=itanium1|-mtune=itanium2] + [-munwind-check=warning|-munwind-check=error] + [-mhint.b=ok|-mhint.b=warning|-mhint.b=error] + [-x|-xexplicit] [-xauto] [-xdebug] + + _Target IP2K options:_ + [-mip2022|-mip2022ext] + + _Target M32C options:_ + [-m32c|-m16c] [-relax] [-h-tick-hex] + + _Target M32R options:_ + [-m32rx|-[no-]warn-explicit-parallel-conflicts| + -W[n]p] + + _Target M680X0 options:_ + [-l] [-m68000|-m68010|-m68020|...] + + _Target M68HC11 options:_ + [-m68hc11|-m68hc12|-m68hcs12] + [-mshort|-mlong] + [-mshort-double|-mlong-double] + [-force-long-branches] [-short-branches] + [-strict-direct-mode] [-print-insn-syntax] + [-print-opcodes] [-generate-example] + + _Target MCORE options:_ + [-jsri2bsr] [-sifilter] [-relax] + [-mcpu=[210|340]] + _Target MICROBLAZE options:_ + + _Target MIPS options:_ + [-nocpp] [-EL] [-EB] [-O[OPTIMIZATION LEVEL]] + [-g[DEBUG LEVEL]] [-G NUM] [-KPIC] [-call_shared] + [-non_shared] [-xgot [-mvxworks-pic] + [-mabi=ABI] [-32] [-n32] [-64] [-mfp32] [-mgp32] + [-march=CPU] [-mtune=CPU] [-mips1] [-mips2] + [-mips3] [-mips4] [-mips5] [-mips32] [-mips32r2] + [-mips64] [-mips64r2] + [-construct-floats] [-no-construct-floats] + [-trap] [-no-break] [-break] [-no-trap] + [-mfix7000] [-mno-fix7000] + [-mips16] [-no-mips16] + [-msmartmips] [-mno-smartmips] + [-mips3d] [-no-mips3d] + [-mdmx] [-no-mdmx] + [-mdsp] [-mno-dsp] + [-mdspr2] [-mno-dspr2] + [-mmt] [-mno-mt] + [-mdebug] [-no-mdebug] + [-mpdr] [-mno-pdr] + + _Target MMIX options:_ + [-fixed-special-register-names] [-globalize-symbols] + [-gnu-syntax] [-relax] [-no-predefined-symbols] + [-no-expand] [-no-merge-gregs] [-x] + [-linker-allocated-gregs] + + _Target PDP11 options:_ + [-mpic|-mno-pic] [-mall] [-mno-extensions] + [-mEXTENSION|-mno-EXTENSION] + [-mCPU] [-mMACHINE] + + _Target picoJava options:_ + [-mb|-me] + + _Target PowerPC options:_ + [-mpwrx|-mpwr2|-mpwr|-m601|-mppc|-mppc32|-m603|-m604| + -m403|-m405|-mppc64|-m620|-mppc64bridge|-mbooke] + [-mcom|-many|-maltivec|-mvsx] [-memb] + [-mregnames|-mno-regnames] + [-mrelocatable|-mrelocatable-lib] + [-mlittle|-mlittle-endian|-mbig|-mbig-endian] + [-msolaris|-mno-solaris] + + _Target s390 options:_ + [-m31|-m64] [-mesa|-mzarch] [-march=CPU] + [-mregnames|-mno-regnames] + [-mwarn-areg-zero] + + _Target SCORE options:_ + [-EB][-EL][-FIXDD][-NWARN] + [-SCORE5][-SCORE5U][-SCORE7][-SCORE3] + [-march=score7][-march=score3] + [-USE_R1][-KPIC][-O0][-G NUM][-V] + + _Target SPARC options:_ + [-Av6|-Av7|-Av8|-Asparclet|-Asparclite + -Av8plus|-Av8plusa|-Av9|-Av9a] + [-xarch=v8plus|-xarch=v8plusa] [-bump] + [-32|-64] + + _Target TIC54X options:_ + [-mcpu=54[123589]|-mcpu=54[56]lp] [-mfar-mode|-mf] + [-merrors-to-file <FILENAME>|-me <FILENAME>] + + + _Target Z80 options:_ + [-z80] [-r800] + [ -ignore-undocumented-instructions] [-Wnud] + [ -ignore-unportable-instructions] [-Wnup] + [ -warn-undocumented-instructions] [-Wud] + [ -warn-unportable-instructions] [-Wup] + [ -forbid-undocumented-instructions] [-Fud] + [ -forbid-unportable-instructions] [-Fup] + + + _Target Xtensa options:_ + [-[no-]text-section-literals] [-[no-]absolute-literals] + [-[no-]target-align] [-[no-]longcalls] + [-[no-]transform] + [-rename-section OLDNAME=NEWNAME] + +`@FILE' + Read command-line options from FILE. The options read are + inserted in place of the original @FILE option. If FILE does not + exist, or cannot be read, then the option will be treated + literally, and not removed. + + Options in FILE are separated by whitespace. A whitespace + character may be included in an option by surrounding the entire + option in either single or double quotes. Any character + (including a backslash) may be included by prefixing the character + to be included with a backslash. The FILE may itself contain + additional @FILE options; any such options will be processed + recursively. + +`-a[cdghlmns]' + Turn on listings, in any of a variety of ways: + + `-ac' + omit false conditionals + + `-ad' + omit debugging directives + + `-ag' + include general information, like as version and options + passed + + `-ah' + include high-level source + + `-al' + include assembly + + `-am' + include macro expansions + + `-an' + omit forms processing + + `-as' + include symbols + + `=file' + set the name of the listing file + + You may combine these options; for example, use `-aln' for assembly + listing without forms processing. The `=file' option, if used, + must be the last one. By itself, `-a' defaults to `-ahls'. + +`--alternate' + Begin in alternate macro mode. *Note `.altmacro': Altmacro. + +`-D' + Ignored. This option is accepted for script compatibility with + calls to other assemblers. + +`--debug-prefix-map OLD=NEW' + When assembling files in directory `OLD', record debugging + information describing them as in `NEW' instead. + +`--defsym SYM=VALUE' + Define the symbol SYM to be VALUE before assembling the input file. + VALUE must be an integer constant. As in C, a leading `0x' + indicates a hexadecimal value, and a leading `0' indicates an octal + value. The value of the symbol can be overridden inside a source + file via the use of a `.set' pseudo-op. + +`-f' + "fast"--skip whitespace and comment preprocessing (assume source is + compiler output). + +`-g' +`--gen-debug' + Generate debugging information for each assembler source line + using whichever debug format is preferred by the target. This + currently means either STABS, ECOFF or DWARF2. + +`--gstabs' + Generate stabs debugging information for each assembler line. This + may help debugging assembler code, if the debugger can handle it. + +`--gstabs+' + Generate stabs debugging information for each assembler line, with + GNU extensions that probably only gdb can handle, and that could + make other debuggers crash or refuse to read your program. This + may help debugging assembler code. Currently the only GNU + extension is the location of the current working directory at + assembling time. + +`--gdwarf-2' + Generate DWARF2 debugging information for each assembler line. + This may help debugging assembler code, if the debugger can handle + it. Note--this option is only supported by some targets, not all + of them. + +`--help' + Print a summary of the command line options and exit. + +`--target-help' + Print a summary of all target specific options and exit. + +`-I DIR' + Add directory DIR to the search list for `.include' directives. + +`-J' + Don't warn about signed overflow. + +`-K' + Issue warnings when difference tables altered for long + displacements. + +`-L' +`--keep-locals' + Keep (in the symbol table) local symbols. These symbols start with + system-specific local label prefixes, typically `.L' for ELF + systems or `L' for traditional a.out systems. *Note Symbol + Names::. + +`--listing-lhs-width=NUMBER' + Set the maximum width, in words, of the output data column for an + assembler listing to NUMBER. + +`--listing-lhs-width2=NUMBER' + Set the maximum width, in words, of the output data column for + continuation lines in an assembler listing to NUMBER. + +`--listing-rhs-width=NUMBER' + Set the maximum width of an input source line, as displayed in a + listing, to NUMBER bytes. + +`--listing-cont-lines=NUMBER' + Set the maximum number of lines printed in a listing for a single + line of input to NUMBER + 1. + +`-o OBJFILE' + Name the object-file output from `as' OBJFILE. + +`-R' + Fold the data section into the text section. + + Set the default size of GAS's hash tables to a prime number close + to NUMBER. Increasing this value can reduce the length of time it + takes the assembler to perform its tasks, at the expense of + increasing the assembler's memory requirements. Similarly + reducing this value can reduce the memory requirements at the + expense of speed. + +`--reduce-memory-overheads' + This option reduces GAS's memory requirements, at the expense of + making the assembly processes slower. Currently this switch is a + synonym for `--hash-size=4051', but in the future it may have + other effects as well. + +`--statistics' + Print the maximum space (in bytes) and total time (in seconds) + used by assembly. + +`--strip-local-absolute' + Remove local absolute symbols from the outgoing symbol table. + +`-v' +`-version' + Print the `as' version. + +`--version' + Print the `as' version and exit. + +`-W' +`--no-warn' + Suppress warning messages. + +`--fatal-warnings' + Treat warnings as errors. + +`--warn' + Don't suppress warning messages or treat them as errors. + +`-w' + Ignored. + +`-x' + Ignored. + +`-Z' + Generate an object file even after errors. + +`-- | FILES ...' + Standard input, or source files to assemble. + + + The following options are available when as is configured for an ARC +processor. + +`-marc[5|6|7|8]' + This option selects the core processor variant. + +`-EB | -EL' + Select either big-endian (-EB) or little-endian (-EL) output. + + The following options are available when as is configured for the ARM +processor family. + +`-mcpu=PROCESSOR[+EXTENSION...]' + Specify which ARM processor variant is the target. + +`-march=ARCHITECTURE[+EXTENSION...]' + Specify which ARM architecture variant is used by the target. + +`-mfpu=FLOATING-POINT-FORMAT' + Select which Floating Point architecture is the target. + +`-mfloat-abi=ABI' + Select which floating point ABI is in use. + +`-mthumb' + Enable Thumb only instruction decoding. + +`-mapcs-32 | -mapcs-26 | -mapcs-float | -mapcs-reentrant' + Select which procedure calling convention is in use. + +`-EB | -EL' + Select either big-endian (-EB) or little-endian (-EL) output. + +`-mthumb-interwork' + Specify that the code has been generated with interworking between + Thumb and ARM code in mind. + +`-k' + Specify that PIC code has been generated. + + See the info pages for documentation of the CRIS-specific options. + + The following options are available when as is configured for a D10V +processor. +`-O' + Optimize output by parallelizing instructions. + + The following options are available when as is configured for a D30V +processor. +`-O' + Optimize output by parallelizing instructions. + +`-n' + Warn when nops are generated. + +`-N' + Warn when a nop after a 32-bit multiply instruction is generated. + + The following options are available when as is configured for the +Intel 80960 processor. + +`-ACA | -ACA_A | -ACB | -ACC | -AKA | -AKB | -AKC | -AMC' + Specify which variant of the 960 architecture is the target. + +`-b' + Add code to collect statistics about branches taken. + +`-no-relax' + Do not alter compare-and-branch instructions for long + displacements; error if necessary. + + + The following options are available when as is configured for the +Ubicom IP2K series. + +`-mip2022ext' + Specifies that the extended IP2022 instructions are allowed. + +`-mip2022' + Restores the default behaviour, which restricts the permitted + instructions to just the basic IP2022 ones. + + + The following options are available when as is configured for the +Renesas M32C and M16C processors. + +`-m32c' + Assemble M32C instructions. + +`-m16c' + Assemble M16C instructions (the default). + +`-relax' + Enable support for link-time relaxations. + +`-h-tick-hex' + Support H'00 style hex constants in addition to 0x00 style. + + + The following options are available when as is configured for the +Renesas M32R (formerly Mitsubishi M32R) series. + +`--m32rx' + Specify which processor in the M32R family is the target. The + default is normally the M32R, but this option changes it to the + M32RX. + +`--warn-explicit-parallel-conflicts or --Wp' + Produce warning messages when questionable parallel constructs are + encountered. + +`--no-warn-explicit-parallel-conflicts or --Wnp' + Do not produce warning messages when questionable parallel + constructs are encountered. + + + The following options are available when as is configured for the +Motorola 68000 series. + +`-l' + Shorten references to undefined symbols, to one word instead of + two. + +`-m68000 | -m68008 | -m68010 | -m68020 | -m68030' +`| -m68040 | -m68060 | -m68302 | -m68331 | -m68332' +`| -m68333 | -m68340 | -mcpu32 | -m5200' + Specify what processor in the 68000 family is the target. The + default is normally the 68020, but this can be changed at + configuration time. + +`-m68881 | -m68882 | -mno-68881 | -mno-68882' + The target machine does (or does not) have a floating-point + coprocessor. The default is to assume a coprocessor for 68020, + 68030, and cpu32. Although the basic 68000 is not compatible with + the 68881, a combination of the two can be specified, since it's + possible to do emulation of the coprocessor instructions with the + main processor. + +`-m68851 | -mno-68851' + The target machine does (or does not) have a memory-management + unit coprocessor. The default is to assume an MMU for 68020 and + up. + + + For details about the PDP-11 machine dependent features options, see +*Note PDP-11-Options::. + +`-mpic | -mno-pic' + Generate position-independent (or position-dependent) code. The + default is `-mpic'. + +`-mall' +`-mall-extensions' + Enable all instruction set extensions. This is the default. + +`-mno-extensions' + Disable all instruction set extensions. + +`-mEXTENSION | -mno-EXTENSION' + Enable (or disable) a particular instruction set extension. + +`-mCPU' + Enable the instruction set extensions supported by a particular + CPU, and disable all other extensions. + +`-mMACHINE' + Enable the instruction set extensions supported by a particular + machine model, and disable all other extensions. + + The following options are available when as is configured for a +picoJava processor. + +`-mb' + Generate "big endian" format output. + +`-ml' + Generate "little endian" format output. + + + The following options are available when as is configured for the +Motorola 68HC11 or 68HC12 series. + +`-m68hc11 | -m68hc12 | -m68hcs12' + Specify what processor is the target. The default is defined by + the configuration option when building the assembler. + +`-mshort' + Specify to use the 16-bit integer ABI. + +`-mlong' + Specify to use the 32-bit integer ABI. + +`-mshort-double' + Specify to use the 32-bit double ABI. + +`-mlong-double' + Specify to use the 64-bit double ABI. + +`--force-long-branches' + Relative branches are turned into absolute ones. This concerns + conditional branches, unconditional branches and branches to a sub + routine. + +`-S | --short-branches' + Do not turn relative branches into absolute ones when the offset + is out of range. + +`--strict-direct-mode' + Do not turn the direct addressing mode into extended addressing + mode when the instruction does not support direct addressing mode. + +`--print-insn-syntax' + Print the syntax of instruction in case of error. + +`--print-opcodes' + print the list of instructions with syntax and then exit. + +`--generate-example' + print an example of instruction for each possible instruction and + then exit. This option is only useful for testing `as'. + + + The following options are available when `as' is configured for the +SPARC architecture: + +`-Av6 | -Av7 | -Av8 | -Asparclet | -Asparclite' +`-Av8plus | -Av8plusa | -Av9 | -Av9a' + Explicitly select a variant of the SPARC architecture. + + `-Av8plus' and `-Av8plusa' select a 32 bit environment. `-Av9' + and `-Av9a' select a 64 bit environment. + + `-Av8plusa' and `-Av9a' enable the SPARC V9 instruction set with + UltraSPARC extensions. + +`-xarch=v8plus | -xarch=v8plusa' + For compatibility with the Solaris v9 assembler. These options are + equivalent to -Av8plus and -Av8plusa, respectively. + +`-bump' + Warn when the assembler switches to another architecture. + + The following options are available when as is configured for the +'c54x architecture. + +`-mfar-mode' + Enable extended addressing mode. All addresses and relocations + will assume extended addressing (usually 23 bits). + +`-mcpu=CPU_VERSION' + Sets the CPU version being compiled for. + +`-merrors-to-file FILENAME' + Redirect error output to a file, for broken systems which don't + support such behaviour in the shell. + + The following options are available when as is configured for a MIPS +processor. + +`-G NUM' + This option sets the largest size of an object that can be + referenced implicitly with the `gp' register. It is only accepted + for targets that use ECOFF format, such as a DECstation running + Ultrix. The default value is 8. + +`-EB' + Generate "big endian" format output. + +`-EL' + Generate "little endian" format output. + +`-mips1' +`-mips2' +`-mips3' +`-mips4' +`-mips5' +`-mips32' +`-mips32r2' +`-mips64' +`-mips64r2' + Generate code for a particular MIPS Instruction Set Architecture + level. `-mips1' is an alias for `-march=r3000', `-mips2' is an + alias for `-march=r6000', `-mips3' is an alias for `-march=r4000' + and `-mips4' is an alias for `-march=r8000'. `-mips5', `-mips32', + `-mips32r2', `-mips64', and `-mips64r2' correspond to generic + `MIPS V', `MIPS32', `MIPS32 Release 2', `MIPS64', and `MIPS64 + Release 2' ISA processors, respectively. + +`-march=CPU' + Generate code for a particular MIPS cpu. + +`-mtune=CPU' + Schedule and tune for a particular MIPS cpu. + +`-mfix7000' +`-mno-fix7000' + Cause nops to be inserted if the read of the destination register + of an mfhi or mflo instruction occurs in the following two + instructions. + +`-mdebug' +`-no-mdebug' + Cause stabs-style debugging output to go into an ECOFF-style + .mdebug section instead of the standard ELF .stabs sections. + +`-mpdr' +`-mno-pdr' + Control generation of `.pdr' sections. + +`-mgp32' +`-mfp32' + The register sizes are normally inferred from the ISA and ABI, but + these flags force a certain group of registers to be treated as 32 + bits wide at all times. `-mgp32' controls the size of + general-purpose registers and `-mfp32' controls the size of + floating-point registers. + +`-mips16' +`-no-mips16' + Generate code for the MIPS 16 processor. This is equivalent to + putting `.set mips16' at the start of the assembly file. + `-no-mips16' turns off this option. + +`-msmartmips' +`-mno-smartmips' + Enables the SmartMIPS extension to the MIPS32 instruction set. + This is equivalent to putting `.set smartmips' at the start of the + assembly file. `-mno-smartmips' turns off this option. + +`-mips3d' +`-no-mips3d' + Generate code for the MIPS-3D Application Specific Extension. + This tells the assembler to accept MIPS-3D instructions. + `-no-mips3d' turns off this option. + +`-mdmx' +`-no-mdmx' + Generate code for the MDMX Application Specific Extension. This + tells the assembler to accept MDMX instructions. `-no-mdmx' turns + off this option. + +`-mdsp' +`-mno-dsp' + Generate code for the DSP Release 1 Application Specific Extension. + This tells the assembler to accept DSP Release 1 instructions. + `-mno-dsp' turns off this option. + +`-mdspr2' +`-mno-dspr2' + Generate code for the DSP Release 2 Application Specific Extension. + This option implies -mdsp. This tells the assembler to accept DSP + Release 2 instructions. `-mno-dspr2' turns off this option. + +`-mmt' +`-mno-mt' + Generate code for the MT Application Specific Extension. This + tells the assembler to accept MT instructions. `-mno-mt' turns + off this option. + +`--construct-floats' +`--no-construct-floats' + The `--no-construct-floats' option disables the construction of + double width floating point constants by loading the two halves of + the value into the two single width floating point registers that + make up the double width register. By default + `--construct-floats' is selected, allowing construction of these + floating point constants. + +`--emulation=NAME' + This option causes `as' to emulate `as' configured for some other + target, in all respects, including output format (choosing between + ELF and ECOFF only), handling of pseudo-opcodes which may generate + debugging information or store symbol table information, and + default endianness. The available configuration names are: + `mipsecoff', `mipself', `mipslecoff', `mipsbecoff', `mipslelf', + `mipsbelf'. The first two do not alter the default endianness + from that of the primary target for which the assembler was + configured; the others change the default to little- or big-endian + as indicated by the `b' or `l' in the name. Using `-EB' or `-EL' + will override the endianness selection in any case. + + This option is currently supported only when the primary target + `as' is configured for is a MIPS ELF or ECOFF target. + Furthermore, the primary target or others specified with + `--enable-targets=...' at configuration time must include support + for the other format, if both are to be available. For example, + the Irix 5 configuration includes support for both. + + Eventually, this option will support more configurations, with more + fine-grained control over the assembler's behavior, and will be + supported for more processors. + +`-nocpp' + `as' ignores this option. It is accepted for compatibility with + the native tools. + +`--trap' +`--no-trap' +`--break' +`--no-break' + Control how to deal with multiplication overflow and division by + zero. `--trap' or `--no-break' (which are synonyms) take a trap + exception (and only work for Instruction Set Architecture level 2 + and higher); `--break' or `--no-trap' (also synonyms, and the + default) take a break exception. + +`-n' + When this option is used, `as' will issue a warning every time it + generates a nop instruction from a macro. + + The following options are available when as is configured for an +MCore processor. + +`-jsri2bsr' +`-nojsri2bsr' + Enable or disable the JSRI to BSR transformation. By default this + is enabled. The command line option `-nojsri2bsr' can be used to + disable it. + +`-sifilter' +`-nosifilter' + Enable or disable the silicon filter behaviour. By default this + is disabled. The default can be overridden by the `-sifilter' + command line option. + +`-relax' + Alter jump instructions for long displacements. + +`-mcpu=[210|340]' + Select the cpu type on the target hardware. This controls which + instructions can be assembled. + +`-EB' + Assemble for a big endian target. + +`-EL' + Assemble for a little endian target. + + + See the info pages for documentation of the MMIX-specific options. + + The following options are available when as is configured for the +s390 processor family. + +`-m31' +`-m64' + Select the word size, either 31/32 bits or 64 bits. + +`-mesa' + +`-mzarch' + Select the architecture mode, either the Enterprise System + Architecture (esa) or the z/Architecture mode (zarch). + +`-march=PROCESSOR' + Specify which s390 processor variant is the target, `g6', `g6', + `z900', `z990', `z9-109', `z9-ec', or `z10'. + +`-mregnames' +`-mno-regnames' + Allow or disallow symbolic names for registers. + +`-mwarn-areg-zero' + Warn whenever the operand for a base or index register has been + specified but evaluates to zero. + + The following options are available when as is configured for an +Xtensa processor. + +`--text-section-literals | --no-text-section-literals' + With `--text-section-literals', literal pools are interspersed in + the text section. The default is `--no-text-section-literals', + which places literals in a separate section in the output file. + These options only affect literals referenced via PC-relative + `L32R' instructions; literals for absolute mode `L32R' + instructions are handled separately. + +`--absolute-literals | --no-absolute-literals' + Indicate to the assembler whether `L32R' instructions use absolute + or PC-relative addressing. The default is to assume absolute + addressing if the Xtensa processor includes the absolute `L32R' + addressing option. Otherwise, only the PC-relative `L32R' mode + can be used. + +`--target-align | --no-target-align' + Enable or disable automatic alignment to reduce branch penalties + at the expense of some code density. The default is + `--target-align'. + +`--longcalls | --no-longcalls' + Enable or disable transformation of call instructions to allow + calls across a greater range of addresses. The default is + `--no-longcalls'. + +`--transform | --no-transform' + Enable or disable all assembler transformations of Xtensa + instructions. The default is `--transform'; `--no-transform' + should be used only in the rare cases when the instructions must + be exactly as specified in the assembly source. + +`--rename-section OLDNAME=NEWNAME' + When generating output sections, rename the OLDNAME section to + NEWNAME. + + The following options are available when as is configured for a Z80 +family processor. +`-z80' + Assemble for Z80 processor. + +`-r800' + Assemble for R800 processor. + +`-ignore-undocumented-instructions' +`-Wnud' + Assemble undocumented Z80 instructions that also work on R800 + without warning. + +`-ignore-unportable-instructions' +`-Wnup' + Assemble all undocumented Z80 instructions without warning. + +`-warn-undocumented-instructions' +`-Wud' + Issue a warning for undocumented Z80 instructions that also work + on R800. + +`-warn-unportable-instructions' +`-Wup' + Issue a warning for undocumented Z80 instructions that do not work + on R800. + +`-forbid-undocumented-instructions' +`-Fud' + Treat all undocumented instructions as errors. + +`-forbid-unportable-instructions' +`-Fup' + Treat undocumented Z80 instructions that do not work on R800 as + errors. + +* Menu: + +* Manual:: Structure of this Manual +* GNU Assembler:: The GNU Assembler +* Object Formats:: Object File Formats +* Command Line:: Command Line +* Input Files:: Input Files +* Object:: Output (Object) File +* Errors:: Error and Warning Messages + + +File: as.info, Node: Manual, Next: GNU Assembler, Up: Overview + +1.1 Structure of this Manual +============================ + +This manual is intended to describe what you need to know to use GNU +`as'. We cover the syntax expected in source files, including notation +for symbols, constants, and expressions; the directives that `as' +understands; and of course how to invoke `as'. + + This manual also describes some of the machine-dependent features of +various flavors of the assembler. + + On the other hand, this manual is _not_ intended as an introduction +to programming in assembly language--let alone programming in general! +In a similar vein, we make no attempt to introduce the machine +architecture; we do _not_ describe the instruction set, standard +mnemonics, registers or addressing modes that are standard to a +particular architecture. You may want to consult the manufacturer's +machine architecture manual for this information. + + +File: as.info, Node: GNU Assembler, Next: Object Formats, Prev: Manual, Up: Overview + +1.2 The GNU Assembler +===================== + +GNU `as' is really a family of assemblers. If you use (or have used) +the GNU assembler on one architecture, you should find a fairly similar +environment when you use it on another architecture. Each version has +much in common with the others, including object file formats, most +assembler directives (often called "pseudo-ops") and assembler syntax. + + `as' is primarily intended to assemble the output of the GNU C +compiler `gcc' for use by the linker `ld'. Nevertheless, we've tried +to make `as' assemble correctly everything that other assemblers for +the same machine would assemble. Any exceptions are documented +explicitly (*note Machine Dependencies::). This doesn't mean `as' +always uses the same syntax as another assembler for the same +architecture; for example, we know of several incompatible versions of +680x0 assembly language syntax. + + Unlike older assemblers, `as' is designed to assemble a source +program in one pass of the source file. This has a subtle impact on the +`.org' directive (*note `.org': Org.). + + +File: as.info, Node: Object Formats, Next: Command Line, Prev: GNU Assembler, Up: Overview + +1.3 Object File Formats +======================= + +The GNU assembler can be configured to produce several alternative +object file formats. For the most part, this does not affect how you +write assembly language programs; but directives for debugging symbols +are typically different in different file formats. *Note Symbol +Attributes: Symbol Attributes. + + +File: as.info, Node: Command Line, Next: Input Files, Prev: Object Formats, Up: Overview + +1.4 Command Line +================ + +After the program name `as', the command line may contain options and +file names. Options may appear in any order, and may be before, after, +or between file names. The order of file names is significant. + + `--' (two hyphens) by itself names the standard input file +explicitly, as one of the files for `as' to assemble. + + Except for `--' any command line argument that begins with a hyphen +(`-') is an option. Each option changes the behavior of `as'. No +option changes the way another option works. An option is a `-' +followed by one or more letters; the case of the letter is important. +All options are optional. + + Some options expect exactly one file name to follow them. The file +name may either immediately follow the option's letter (compatible with +older assemblers) or it may be the next command argument (GNU +standard). These two command lines are equivalent: + + as -o my-object-file.o mumble.s + as -omy-object-file.o mumble.s + + +File: as.info, Node: Input Files, Next: Object, Prev: Command Line, Up: Overview + +1.5 Input Files +=============== + +We use the phrase "source program", abbreviated "source", to describe +the program input to one run of `as'. The program may be in one or +more files; how the source is partitioned into files doesn't change the +meaning of the source. + + The source program is a concatenation of the text in all the files, +in the order specified. + + Each time you run `as' it assembles exactly one source program. The +source program is made up of one or more files. (The standard input is +also a file.) + + You give `as' a command line that has zero or more input file names. +The input files are read (from left file name to right). A command +line argument (in any position) that has no special meaning is taken to +be an input file name. + + If you give `as' no file names it attempts to read one input file +from the `as' standard input, which is normally your terminal. You may +have to type <ctl-D> to tell `as' there is no more program to assemble. + + Use `--' if you need to explicitly name the standard input file in +your command line. + + If the source is empty, `as' produces a small, empty object file. + +Filenames and Line-numbers +-------------------------- + +There are two ways of locating a line in the input file (or files) and +either may be used in reporting error messages. One way refers to a +line number in a physical file; the other refers to a line number in a +"logical" file. *Note Error and Warning Messages: Errors. + + "Physical files" are those files named in the command line given to +`as'. + + "Logical files" are simply names declared explicitly by assembler +directives; they bear no relation to physical files. Logical file +names help error messages reflect the original source file, when `as' +source is itself synthesized from other files. `as' understands the +`#' directives emitted by the `gcc' preprocessor. See also *Note +`.file': File. + + +File: as.info, Node: Object, Next: Errors, Prev: Input Files, Up: Overview + +1.6 Output (Object) File +======================== + +Every time you run `as' it produces an output file, which is your +assembly language program translated into numbers. This file is the +object file. Its default name is `a.out'. You can give it another +name by using the `-o' option. Conventionally, object file names end +with `.o'. The default name is used for historical reasons: older +assemblers were capable of assembling self-contained programs directly +into a runnable program. (For some formats, this isn't currently +possible, but it can be done for the `a.out' format.) + + The object file is meant for input to the linker `ld'. It contains +assembled program code, information to help `ld' integrate the +assembled program into a runnable file, and (optionally) symbolic +information for the debugger. + + +File: as.info, Node: Errors, Prev: Object, Up: Overview + +1.7 Error and Warning Messages +============================== + +`as' may write warnings and error messages to the standard error file +(usually your terminal). This should not happen when a compiler runs +`as' automatically. Warnings report an assumption made so that `as' +could keep assembling a flawed program; errors report a grave problem +that stops the assembly. + + Warning messages have the format + + file_name:NNN:Warning Message Text + +(where NNN is a line number). If a logical file name has been given +(*note `.file': File.) it is used for the filename, otherwise the name +of the current input file is used. If a logical line number was given +(*note `.line': Line.) then it is used to calculate the number printed, +otherwise the actual line in the current source file is printed. The +message text is intended to be self explanatory (in the grand Unix +tradition). + + Error messages have the format + file_name:NNN:FATAL:Error Message Text + The file name and line number are derived as for warning messages. +The actual message text may be rather less explanatory because many of +them aren't supposed to happen. + + +File: as.info, Node: Invoking, Next: Syntax, Prev: Overview, Up: Top + +2 Command-Line Options +********************** + +This chapter describes command-line options available in _all_ versions +of the GNU assembler; see *Note Machine Dependencies::, for options +specific to particular machine architectures. + + If you are invoking `as' via the GNU C compiler, you can use the +`-Wa' option to pass arguments through to the assembler. The assembler +arguments must be separated from each other (and the `-Wa') by commas. +For example: + + gcc -c -g -O -Wa,-alh,-L file.c + +This passes two options to the assembler: `-alh' (emit a listing to +standard output with high-level and assembly source) and `-L' (retain +local symbols in the symbol table). + + Usually you do not need to use this `-Wa' mechanism, since many +compiler command-line options are automatically passed to the assembler +by the compiler. (You can call the GNU compiler driver with the `-v' +option to see precisely what options it passes to each compilation +pass, including the assembler.) + +* Menu: + +* a:: -a[cdghlns] enable listings +* alternate:: --alternate enable alternate macro syntax +* D:: -D for compatibility +* f:: -f to work faster +* I:: -I for .include search path + +* K:: -K for difference tables + +* L:: -L to retain local symbols +* listing:: --listing-XXX to configure listing output +* M:: -M or --mri to assemble in MRI compatibility mode +* MD:: --MD for dependency tracking +* o:: -o to name the object file +* R:: -R to join data and text sections +* statistics:: --statistics to see statistics about assembly +* traditional-format:: --traditional-format for compatible output +* v:: -v to announce version +* W:: -W, --no-warn, --warn, --fatal-warnings to control warnings +* Z:: -Z to make object file even after errors + + +File: as.info, Node: a, Next: alternate, Up: Invoking + +2.1 Enable Listings: `-a[cdghlns]' +================================== + +These options enable listing output from the assembler. By itself, +`-a' requests high-level, assembly, and symbols listing. You can use +other letters to select specific options for the list: `-ah' requests a +high-level language listing, `-al' requests an output-program assembly +listing, and `-as' requests a symbol table listing. High-level +listings require that a compiler debugging option like `-g' be used, +and that assembly listings (`-al') be requested also. + + Use the `-ag' option to print a first section with general assembly +information, like as version, switches passed, or time stamp. + + Use the `-ac' option to omit false conditionals from a listing. Any +lines which are not assembled because of a false `.if' (or `.ifdef', or +any other conditional), or a true `.if' followed by an `.else', will be +omitted from the listing. + + Use the `-ad' option to omit debugging directives from the listing. + + Once you have specified one of these options, you can further control +listing output and its appearance using the directives `.list', +`.nolist', `.psize', `.eject', `.title', and `.sbttl'. The `-an' +option turns off all forms processing. If you do not request listing +output with one of the `-a' options, the listing-control directives +have no effect. + + The letters after `-a' may be combined into one option, _e.g._, +`-aln'. + + Note if the assembler source is coming from the standard input (e.g., +because it is being created by `gcc' and the `-pipe' command line switch +is being used) then the listing will not contain any comments or +preprocessor directives. This is because the listing code buffers +input source lines from stdin only after they have been preprocessed by +the assembler. This reduces memory usage and makes the code more +efficient. + + +File: as.info, Node: alternate, Next: D, Prev: a, Up: Invoking + +2.2 `--alternate' +================= + +Begin in alternate macro mode, see *Note `.altmacro': Altmacro. + + +File: as.info, Node: D, Next: f, Prev: alternate, Up: Invoking + +2.3 `-D' +======== + +This option has no effect whatsoever, but it is accepted to make it more +likely that scripts written for other assemblers also work with `as'. + + +File: as.info, Node: f, Next: I, Prev: D, Up: Invoking + +2.4 Work Faster: `-f' +===================== + +`-f' should only be used when assembling programs written by a +(trusted) compiler. `-f' stops the assembler from doing whitespace and +comment preprocessing on the input file(s) before assembling them. +*Note Preprocessing: Preprocessing. + + _Warning:_ if you use `-f' when the files actually need to be + preprocessed (if they contain comments, for example), `as' does + not work correctly. + + +File: as.info, Node: I, Next: K, Prev: f, Up: Invoking + +2.5 `.include' Search Path: `-I' PATH +===================================== + +Use this option to add a PATH to the list of directories `as' searches +for files specified in `.include' directives (*note `.include': +Include.). You may use `-I' as many times as necessary to include a +variety of paths. The current working directory is always searched +first; after that, `as' searches any `-I' directories in the same order +as they were specified (left to right) on the command line. + + +File: as.info, Node: K, Next: L, Prev: I, Up: Invoking + +2.6 Difference Tables: `-K' +=========================== + +`as' sometimes alters the code emitted for directives of the form +`.word SYM1-SYM2'. *Note `.word': Word. You can use the `-K' option +if you want a warning issued when this is done. + + +File: as.info, Node: L, Next: listing, Prev: K, Up: Invoking + +2.7 Include Local Symbols: `-L' +=============================== + +Symbols beginning with system-specific local label prefixes, typically +`.L' for ELF systems or `L' for traditional a.out systems, are called +"local symbols". *Note Symbol Names::. Normally you do not see such +symbols when debugging, because they are intended for the use of +programs (like compilers) that compose assembler programs, not for your +notice. Normally both `as' and `ld' discard such symbols, so you do +not normally debug with them. + + This option tells `as' to retain those local symbols in the object +file. Usually if you do this you also tell the linker `ld' to preserve +those symbols. + + +File: as.info, Node: listing, Next: M, Prev: L, Up: Invoking + +2.8 Configuring listing output: `--listing' +=========================================== + +The listing feature of the assembler can be enabled via the command +line switch `-a' (*note a::). This feature combines the input source +file(s) with a hex dump of the corresponding locations in the output +object file, and displays them as a listing file. The format of this +listing can be controlled by directives inside the assembler source +(i.e., `.list' (*note List::), `.title' (*note Title::), `.sbttl' +(*note Sbttl::), `.psize' (*note Psize::), and `.eject' (*note Eject::) +and also by the following switches: + +`--listing-lhs-width=`number'' + Sets the maximum width, in words, of the first line of the hex + byte dump. This dump appears on the left hand side of the listing + output. + +`--listing-lhs-width2=`number'' + Sets the maximum width, in words, of any further lines of the hex + byte dump for a given input source line. If this value is not + specified, it defaults to being the same as the value specified + for `--listing-lhs-width'. If neither switch is used the default + is to one. + +`--listing-rhs-width=`number'' + Sets the maximum width, in characters, of the source line that is + displayed alongside the hex dump. The default value for this + parameter is 100. The source line is displayed on the right hand + side of the listing output. + +`--listing-cont-lines=`number'' + Sets the maximum number of continuation lines of hex dump that + will be displayed for a given single line of source input. The + default value is 4. + + +File: as.info, Node: M, Next: MD, Prev: listing, Up: Invoking + +2.9 Assemble in MRI Compatibility Mode: `-M' +============================================ + +The `-M' or `--mri' option selects MRI compatibility mode. This +changes the syntax and pseudo-op handling of `as' to make it compatible +with the `ASM68K' or the `ASM960' (depending upon the configured +target) assembler from Microtec Research. The exact nature of the MRI +syntax will not be documented here; see the MRI manuals for more +information. Note in particular that the handling of macros and macro +arguments is somewhat different. The purpose of this option is to +permit assembling existing MRI assembler code using `as'. + + The MRI compatibility is not complete. Certain operations of the +MRI assembler depend upon its object file format, and can not be +supported using other object file formats. Supporting these would +require enhancing each object file format individually. These are: + + * global symbols in common section + + The m68k MRI assembler supports common sections which are merged + by the linker. Other object file formats do not support this. + `as' handles common sections by treating them as a single common + symbol. It permits local symbols to be defined within a common + section, but it can not support global symbols, since it has no + way to describe them. + + * complex relocations + + The MRI assemblers support relocations against a negated section + address, and relocations which combine the start addresses of two + or more sections. These are not support by other object file + formats. + + * `END' pseudo-op specifying start address + + The MRI `END' pseudo-op permits the specification of a start + address. This is not supported by other object file formats. The + start address may instead be specified using the `-e' option to + the linker, or in a linker script. + + * `IDNT', `.ident' and `NAME' pseudo-ops + + The MRI `IDNT', `.ident' and `NAME' pseudo-ops assign a module + name to the output file. This is not supported by other object + file formats. + + * `ORG' pseudo-op + + The m68k MRI `ORG' pseudo-op begins an absolute section at a given + address. This differs from the usual `as' `.org' pseudo-op, which + changes the location within the current section. Absolute + sections are not supported by other object file formats. The + address of a section may be assigned within a linker script. + + There are some other features of the MRI assembler which are not +supported by `as', typically either because they are difficult or +because they seem of little consequence. Some of these may be +supported in future releases. + + * EBCDIC strings + + EBCDIC strings are not supported. + + * packed binary coded decimal + + Packed binary coded decimal is not supported. This means that the + `DC.P' and `DCB.P' pseudo-ops are not supported. + + * `FEQU' pseudo-op + + The m68k `FEQU' pseudo-op is not supported. + + * `NOOBJ' pseudo-op + + The m68k `NOOBJ' pseudo-op is not supported. + + * `OPT' branch control options + + The m68k `OPT' branch control options--`B', `BRS', `BRB', `BRL', + and `BRW'--are ignored. `as' automatically relaxes all branches, + whether forward or backward, to an appropriate size, so these + options serve no purpose. + + * `OPT' list control options + + The following m68k `OPT' list control options are ignored: `C', + `CEX', `CL', `CRE', `E', `G', `I', `M', `MEX', `MC', `MD', `X'. + + * other `OPT' options + + The following m68k `OPT' options are ignored: `NEST', `O', `OLD', + `OP', `P', `PCO', `PCR', `PCS', `R'. + + * `OPT' `D' option is default + + The m68k `OPT' `D' option is the default, unlike the MRI assembler. + `OPT NOD' may be used to turn it off. + + * `XREF' pseudo-op. + + The m68k `XREF' pseudo-op is ignored. + + * `.debug' pseudo-op + + The i960 `.debug' pseudo-op is not supported. + + * `.extended' pseudo-op + + The i960 `.extended' pseudo-op is not supported. + + * `.list' pseudo-op. + + The various options of the i960 `.list' pseudo-op are not + supported. + + * `.optimize' pseudo-op + + The i960 `.optimize' pseudo-op is not supported. + + * `.output' pseudo-op + + The i960 `.output' pseudo-op is not supported. + + * `.setreal' pseudo-op + + The i960 `.setreal' pseudo-op is not supported. + + + +File: as.info, Node: MD, Next: o, Prev: M, Up: Invoking + +2.10 Dependency Tracking: `--MD' +================================ + +`as' can generate a dependency file for the file it creates. This file +consists of a single rule suitable for `make' describing the +dependencies of the main source file. + + The rule is written to the file named in its argument. + + This feature is used in the automatic updating of makefiles. + + +File: as.info, Node: o, Next: R, Prev: MD, Up: Invoking + +2.11 Name the Object File: `-o' +=============================== + +There is always one object file output when you run `as'. By default +it has the name `a.out' (or `b.out', for Intel 960 targets only). You +use this option (which takes exactly one filename) to give the object +file a different name. + + Whatever the object file is called, `as' overwrites any existing +file of the same name. + + +File: as.info, Node: R, Next: statistics, Prev: o, Up: Invoking + +2.12 Join Data and Text Sections: `-R' +====================================== + +`-R' tells `as' to write the object file as if all data-section data +lives in the text section. This is only done at the very last moment: +your binary data are the same, but data section parts are relocated +differently. The data section part of your object file is zero bytes +long because all its bytes are appended to the text section. (*Note +Sections and Relocation: Sections.) + + When you specify `-R' it would be possible to generate shorter +address displacements (because we do not have to cross between text and +data section). We refrain from doing this simply for compatibility with +older versions of `as'. In future, `-R' may work this way. + + When `as' is configured for COFF or ELF output, this option is only +useful if you use sections named `.text' and `.data'. + + `-R' is not supported for any of the HPPA targets. Using `-R' +generates a warning from `as'. + + +File: as.info, Node: statistics, Next: traditional-format, Prev: R, Up: Invoking + +2.13 Display Assembly Statistics: `--statistics' +================================================ + +Use `--statistics' to display two statistics about the resources used by +`as': the maximum amount of space allocated during the assembly (in +bytes), and the total execution time taken for the assembly (in CPU +seconds). + + +File: as.info, Node: traditional-format, Next: v, Prev: statistics, Up: Invoking + +2.14 Compatible Output: `--traditional-format' +============================================== + +For some targets, the output of `as' is different in some ways from the +output of some existing assembler. This switch requests `as' to use +the traditional format instead. + + For example, it disables the exception frame optimizations which +`as' normally does by default on `gcc' output. + + +File: as.info, Node: v, Next: W, Prev: traditional-format, Up: Invoking + +2.15 Announce Version: `-v' +=========================== + +You can find out what version of as is running by including the option +`-v' (which you can also spell as `-version') on the command line. + + +File: as.info, Node: W, Next: Z, Prev: v, Up: Invoking + +2.16 Control Warnings: `-W', `--warn', `--no-warn', `--fatal-warnings' +====================================================================== + +`as' should never give a warning or error message when assembling +compiler output. But programs written by people often cause `as' to +give a warning that a particular assumption was made. All such +warnings are directed to the standard error file. + + If you use the `-W' and `--no-warn' options, no warnings are issued. +This only affects the warning messages: it does not change any +particular of how `as' assembles your file. Errors, which stop the +assembly, are still reported. + + If you use the `--fatal-warnings' option, `as' considers files that +generate warnings to be in error. + + You can switch these options off again by specifying `--warn', which +causes warnings to be output as usual. + + +File: as.info, Node: Z, Prev: W, Up: Invoking + +2.17 Generate Object File in Spite of Errors: `-Z' +================================================== + +After an error message, `as' normally produces no output. If for some +reason you are interested in object file output even after `as' gives +an error message on your program, use the `-Z' option. If there are +any errors, `as' continues anyways, and writes an object file after a +final warning message of the form `N errors, M warnings, generating bad +object file.' + + +File: as.info, Node: Syntax, Next: Sections, Prev: Invoking, Up: Top + +3 Syntax +******** + +This chapter describes the machine-independent syntax allowed in a +source file. `as' syntax is similar to what many other assemblers use; +it is inspired by the BSD 4.2 assembler, except that `as' does not +assemble Vax bit-fields. + +* Menu: + +* Preprocessing:: Preprocessing +* Whitespace:: Whitespace +* Comments:: Comments +* Symbol Intro:: Symbols +* Statements:: Statements +* Constants:: Constants + + +File: as.info, Node: Preprocessing, Next: Whitespace, Up: Syntax + +3.1 Preprocessing +================= + +The `as' internal preprocessor: + * adjusts and removes extra whitespace. It leaves one space or tab + before the keywords on a line, and turns any other whitespace on + the line into a single space. + + * removes all comments, replacing them with a single space, or an + appropriate number of newlines. + + * converts character constants into the appropriate numeric values. + + It does not do macro processing, include file handling, or anything +else you may get from your C compiler's preprocessor. You can do +include file processing with the `.include' directive (*note +`.include': Include.). You can use the GNU C compiler driver to get +other "CPP" style preprocessing by giving the input file a `.S' suffix. +*Note Options Controlling the Kind of Output: (gcc.info)Overall +Options. + + Excess whitespace, comments, and character constants cannot be used +in the portions of the input text that are not preprocessed. + + If the first line of an input file is `#NO_APP' or if you use the +`-f' option, whitespace and comments are not removed from the input +file. Within an input file, you can ask for whitespace and comment +removal in specific portions of the by putting a line that says `#APP' +before the text that may contain whitespace or comments, and putting a +line that says `#NO_APP' after this text. This feature is mainly +intend to support `asm' statements in compilers whose output is +otherwise free of comments and whitespace. + + +File: as.info, Node: Whitespace, Next: Comments, Prev: Preprocessing, Up: Syntax + +3.2 Whitespace +============== + +"Whitespace" is one or more blanks or tabs, in any order. Whitespace +is used to separate symbols, and to make programs neater for people to +read. Unless within character constants (*note Character Constants: +Characters.), any whitespace means the same as exactly one space. + + +File: as.info, Node: Comments, Next: Symbol Intro, Prev: Whitespace, Up: Syntax + +3.3 Comments +============ + +There are two ways of rendering comments to `as'. In both cases the +comment is equivalent to one space. + + Anything from `/*' through the next `*/' is a comment. This means +you may not nest these comments. + + /* + The only way to include a newline ('\n') in a comment + is to use this sort of comment. + */ + + /* This sort of comment does not nest. */ + + Anything from the "line comment" character to the next newline is +considered a comment and is ignored. The line comment character is `;' +on the ARC; `@' on the ARM; `;' for the H8/300 family; `;' for the HPPA; +`#' on the i386 and x86-64; `#' on the i960; `;' for the PDP-11; `;' +for picoJava; `#' for Motorola PowerPC; `#' for IBM S/390; `#' for the +Sunplus SCORE; `!' for the Renesas / SuperH SH; `!' on the SPARC; `#' +on the ip2k; `#' on the m32c; `#' on the m32r; `|' on the 680x0; `#' on +the 68HC11 and 68HC12; `#' on the Vax; `;' for the Z80; `!' for the +Z8000; `#' on the V850; `#' for Xtensa systems; see *Note Machine +Dependencies::. + + On some machines there are two different line comment characters. +One character only begins a comment if it is the first non-whitespace +character on a line, while the other always begins a comment. + + The V850 assembler also supports a double dash as starting a comment +that extends to the end of the line. + + `--'; + + To be compatible with past assemblers, lines that begin with `#' +have a special interpretation. Following the `#' should be an absolute +expression (*note Expressions::): the logical line number of the _next_ +line. Then a string (*note Strings: Strings.) is allowed: if present +it is a new logical file name. The rest of the line, if any, should be +whitespace. + + If the first non-whitespace characters on the line are not numeric, +the line is ignored. (Just like a comment.) + + # This is an ordinary comment. + # 42-6 "new_file_name" # New logical file name + # This is logical line # 36. + This feature is deprecated, and may disappear from future versions +of `as'. + + +File: as.info, Node: Symbol Intro, Next: Statements, Prev: Comments, Up: Syntax + +3.4 Symbols +=========== + +A "symbol" is one or more characters chosen from the set of all letters +(both upper and lower case), digits and the three characters `_.$'. On +most machines, you can also use `$' in symbol names; exceptions are +noted in *Note Machine Dependencies::. No symbol may begin with a +digit. Case is significant. There is no length limit: all characters +are significant. Symbols are delimited by characters not in that set, +or by the beginning of a file (since the source program must end with a +newline, the end of a file is not a possible symbol delimiter). *Note +Symbols::. + + +File: as.info, Node: Statements, Next: Constants, Prev: Symbol Intro, Up: Syntax + +3.5 Statements +============== + +A "statement" ends at a newline character (`\n') or line separator +character. (The line separator is usually `;', unless this conflicts +with the comment character; see *Note Machine Dependencies::.) The +newline or separator character is considered part of the preceding +statement. Newlines and separators within character constants are an +exception: they do not end statements. + +It is an error to end any statement with end-of-file: the last +character of any input file should be a newline. + + An empty statement is allowed, and may include whitespace. It is +ignored. + + A statement begins with zero or more labels, optionally followed by a +key symbol which determines what kind of statement it is. The key +symbol determines the syntax of the rest of the statement. If the +symbol begins with a dot `.' then the statement is an assembler +directive: typically valid for any computer. If the symbol begins with +a letter the statement is an assembly language "instruction": it +assembles into a machine language instruction. Different versions of +`as' for different computers recognize different instructions. In +fact, the same symbol may represent a different instruction in a +different computer's assembly language. + + A label is a symbol immediately followed by a colon (`:'). +Whitespace before a label or after a colon is permitted, but you may not +have whitespace between a label's symbol and its colon. *Note Labels::. + + For HPPA targets, labels need not be immediately followed by a +colon, but the definition of a label must begin in column zero. This +also implies that only one label may be defined on each line. + + label: .directive followed by something + another_label: # This is an empty statement. + instruction operand_1, operand_2, ... + + +File: as.info, Node: Constants, Prev: Statements, Up: Syntax + +3.6 Constants +============= + +A constant is a number, written so that its value is known by +inspection, without knowing any context. Like this: + .byte 74, 0112, 092, 0x4A, 0X4a, 'J, '\J # All the same value. + .ascii "Ring the bell\7" # A string constant. + .octa 0x123456789abcdef0123456789ABCDEF0 # A bignum. + .float 0f-314159265358979323846264338327\ + 95028841971.693993751E-40 # - pi, a flonum. + +* Menu: + +* Characters:: Character Constants +* Numbers:: Number Constants + + +File: as.info, Node: Characters, Next: Numbers, Up: Constants + +3.6.1 Character Constants +------------------------- + +There are two kinds of character constants. A "character" stands for +one character in one byte and its value may be used in numeric +expressions. String constants (properly called string _literals_) are +potentially many bytes and their values may not be used in arithmetic +expressions. + +* Menu: + +* Strings:: Strings +* Chars:: Characters + + +File: as.info, Node: Strings, Next: Chars, Up: Characters + +3.6.1.1 Strings +............... + +A "string" is written between double-quotes. It may contain +double-quotes or null characters. The way to get special characters +into a string is to "escape" these characters: precede them with a +backslash `\' character. For example `\\' represents one backslash: +the first `\' is an escape which tells `as' to interpret the second +character literally as a backslash (which prevents `as' from +recognizing the second `\' as an escape character). The complete list +of escapes follows. + +`\b' + Mnemonic for backspace; for ASCII this is octal code 010. + +`\f' + Mnemonic for FormFeed; for ASCII this is octal code 014. + +`\n' + Mnemonic for newline; for ASCII this is octal code 012. + +`\r' + Mnemonic for carriage-Return; for ASCII this is octal code 015. + +`\t' + Mnemonic for horizontal Tab; for ASCII this is octal code 011. + +`\ DIGIT DIGIT DIGIT' + An octal character code. The numeric code is 3 octal digits. For + compatibility with other Unix systems, 8 and 9 are accepted as + digits: for example, `\008' has the value 010, and `\009' the + value 011. + +`\`x' HEX-DIGITS...' + A hex character code. All trailing hex digits are combined. + Either upper or lower case `x' works. + +`\\' + Represents one `\' character. + +`\"' + Represents one `"' character. Needed in strings to represent this + character, because an unescaped `"' would end the string. + +`\ ANYTHING-ELSE' + Any other character when escaped by `\' gives a warning, but + assembles as if the `\' was not present. The idea is that if you + used an escape sequence you clearly didn't want the literal + interpretation of the following character. However `as' has no + other interpretation, so `as' knows it is giving you the wrong + code and warns you of the fact. + + Which characters are escapable, and what those escapes represent, +varies widely among assemblers. The current set is what we think the +BSD 4.2 assembler recognizes, and is a subset of what most C compilers +recognize. If you are in doubt, do not use an escape sequence. + + +File: as.info, Node: Chars, Prev: Strings, Up: Characters + +3.6.1.2 Characters +.................. + +A single character may be written as a single quote immediately +followed by that character. The same escapes apply to characters as to +strings. So if you want to write the character backslash, you must +write `'\\' where the first `\' escapes the second `\'. As you can +see, the quote is an acute accent, not a grave accent. A newline +immediately following an acute accent is taken as a literal character +and does not count as the end of a statement. The value of a character +constant in a numeric expression is the machine's byte-wide code for +that character. `as' assumes your character code is ASCII: `'A' means +65, `'B' means 66, and so on. + + +File: as.info, Node: Numbers, Prev: Characters, Up: Constants + +3.6.2 Number Constants +---------------------- + +`as' distinguishes three kinds of numbers according to how they are +stored in the target machine. _Integers_ are numbers that would fit +into an `int' in the C language. _Bignums_ are integers, but they are +stored in more than 32 bits. _Flonums_ are floating point numbers, +described below. + +* Menu: + +* Integers:: Integers +* Bignums:: Bignums +* Flonums:: Flonums + + +File: as.info, Node: Integers, Next: Bignums, Up: Numbers + +3.6.2.1 Integers +................ + +A binary integer is `0b' or `0B' followed by zero or more of the binary +digits `01'. + + An octal integer is `0' followed by zero or more of the octal digits +(`01234567'). + + A decimal integer starts with a non-zero digit followed by zero or +more digits (`0123456789'). + + A hexadecimal integer is `0x' or `0X' followed by one or more +hexadecimal digits chosen from `0123456789abcdefABCDEF'. + + Integers have the usual values. To denote a negative integer, use +the prefix operator `-' discussed under expressions (*note Prefix +Operators: Prefix Ops.). + + +File: as.info, Node: Bignums, Next: Flonums, Prev: Integers, Up: Numbers + +3.6.2.2 Bignums +............... + +A "bignum" has the same syntax and semantics as an integer except that +the number (or its negative) takes more than 32 bits to represent in +binary. The distinction is made because in some places integers are +permitted while bignums are not. + + +File: as.info, Node: Flonums, Prev: Bignums, Up: Numbers + +3.6.2.3 Flonums +............... + +A "flonum" represents a floating point number. The translation is +indirect: a decimal floating point number from the text is converted by +`as' to a generic binary floating point number of more than sufficient +precision. This generic floating point number is converted to a +particular computer's floating point format (or formats) by a portion +of `as' specialized to that computer. + + A flonum is written by writing (in order) + * The digit `0'. (`0' is optional on the HPPA.) + + * A letter, to tell `as' the rest of the number is a flonum. `e' is + recommended. Case is not important. + + On the H8/300, Renesas / SuperH SH, and AMD 29K architectures, the + letter must be one of the letters `DFPRSX' (in upper or lower + case). + + On the ARC, the letter must be one of the letters `DFRS' (in upper + or lower case). + + On the Intel 960 architecture, the letter must be one of the + letters `DFT' (in upper or lower case). + + On the HPPA architecture, the letter must be `E' (upper case only). + + * An optional sign: either `+' or `-'. + + * An optional "integer part": zero or more decimal digits. + + * An optional "fractional part": `.' followed by zero or more + decimal digits. + + * An optional exponent, consisting of: + + * An `E' or `e'. + + * Optional sign: either `+' or `-'. + + * One or more decimal digits. + + + At least one of the integer part or the fractional part must be +present. The floating point number has the usual base-10 value. + + `as' does all processing using integers. Flonums are computed +independently of any floating point hardware in the computer running +`as'. + + +File: as.info, Node: Sections, Next: Symbols, Prev: Syntax, Up: Top + +4 Sections and Relocation +************************* + +* Menu: + +* Secs Background:: Background +* Ld Sections:: Linker Sections +* As Sections:: Assembler Internal Sections +* Sub-Sections:: Sub-Sections +* bss:: bss Section + + +File: as.info, Node: Secs Background, Next: Ld Sections, Up: Sections + +4.1 Background +============== + +Roughly, a section is a range of addresses, with no gaps; all data "in" +those addresses is treated the same for some particular purpose. For +example there may be a "read only" section. + + The linker `ld' reads many object files (partial programs) and +combines their contents to form a runnable program. When `as' emits an +object file, the partial program is assumed to start at address 0. +`ld' assigns the final addresses for the partial program, so that +different partial programs do not overlap. This is actually an +oversimplification, but it suffices to explain how `as' uses sections. + + `ld' moves blocks of bytes of your program to their run-time +addresses. These blocks slide to their run-time addresses as rigid +units; their length does not change and neither does the order of bytes +within them. Such a rigid unit is called a _section_. Assigning +run-time addresses to sections is called "relocation". It includes the +task of adjusting mentions of object-file addresses so they refer to +the proper run-time addresses. For the H8/300, and for the Renesas / +SuperH SH, `as' pads sections if needed to ensure they end on a word +(sixteen bit) boundary. + + An object file written by `as' has at least three sections, any of +which may be empty. These are named "text", "data" and "bss" sections. + + When it generates COFF or ELF output, `as' can also generate +whatever other named sections you specify using the `.section' +directive (*note `.section': Section.). If you do not use any +directives that place output in the `.text' or `.data' sections, these +sections still exist, but are empty. + + When `as' generates SOM or ELF output for the HPPA, `as' can also +generate whatever other named sections you specify using the `.space' +and `.subspace' directives. See `HP9000 Series 800 Assembly Language +Reference Manual' (HP 92432-90001) for details on the `.space' and +`.subspace' assembler directives. + + Additionally, `as' uses different names for the standard text, data, +and bss sections when generating SOM output. Program text is placed +into the `$CODE$' section, data into `$DATA$', and BSS into `$BSS$'. + + Within the object file, the text section starts at address `0', the +data section follows, and the bss section follows the data section. + + When generating either SOM or ELF output files on the HPPA, the text +section starts at address `0', the data section at address `0x4000000', +and the bss section follows the data section. + + To let `ld' know which data changes when the sections are relocated, +and how to change that data, `as' also writes to the object file +details of the relocation needed. To perform relocation `ld' must +know, each time an address in the object file is mentioned: + * Where in the object file is the beginning of this reference to an + address? + + * How long (in bytes) is this reference? + + * Which section does the address refer to? What is the numeric + value of + (ADDRESS) - (START-ADDRESS OF SECTION)? + + * Is the reference to an address "Program-Counter relative"? + + In fact, every address `as' ever uses is expressed as + (SECTION) + (OFFSET INTO SECTION) + Further, most expressions `as' computes have this section-relative +nature. (For some object formats, such as SOM for the HPPA, some +expressions are symbol-relative instead.) + + In this manual we use the notation {SECNAME N} to mean "offset N +into section SECNAME." + + Apart from text, data and bss sections you need to know about the +"absolute" section. When `ld' mixes partial programs, addresses in the +absolute section remain unchanged. For example, address `{absolute 0}' +is "relocated" to run-time address 0 by `ld'. Although the linker +never arranges two partial programs' data sections with overlapping +addresses after linking, _by definition_ their absolute sections must +overlap. Address `{absolute 239}' in one part of a program is always +the same address when the program is running as address `{absolute +239}' in any other part of the program. + + The idea of sections is extended to the "undefined" section. Any +address whose section is unknown at assembly time is by definition +rendered {undefined U}--where U is filled in later. Since numbers are +always defined, the only way to generate an undefined address is to +mention an undefined symbol. A reference to a named common block would +be such a symbol: its value is unknown at assembly time so it has +section _undefined_. + + By analogy the word _section_ is used to describe groups of sections +in the linked program. `ld' puts all partial programs' text sections +in contiguous addresses in the linked program. It is customary to +refer to the _text section_ of a program, meaning all the addresses of +all partial programs' text sections. Likewise for data and bss +sections. + + Some sections are manipulated by `ld'; others are invented for use +of `as' and have no meaning except during assembly. + + +File: as.info, Node: Ld Sections, Next: As Sections, Prev: Secs Background, Up: Sections + +4.2 Linker Sections +=================== + +`ld' deals with just four kinds of sections, summarized below. + +*named sections* +*text section* +*data section* + These sections hold your program. `as' and `ld' treat them as + separate but equal sections. Anything you can say of one section + is true of another. When the program is running, however, it is + customary for the text section to be unalterable. The text + section is often shared among processes: it contains instructions, + constants and the like. The data section of a running program is + usually alterable: for example, C variables would be stored in the + data section. + +*bss section* + This section contains zeroed bytes when your program begins + running. It is used to hold uninitialized variables or common + storage. The length of each partial program's bss section is + important, but because it starts out containing zeroed bytes there + is no need to store explicit zero bytes in the object file. The + bss section was invented to eliminate those explicit zeros from + object files. + +*absolute section* + Address 0 of this section is always "relocated" to runtime address + 0. This is useful if you want to refer to an address that `ld' + must not change when relocating. In this sense we speak of + absolute addresses being "unrelocatable": they do not change + during relocation. + +*undefined section* + This "section" is a catch-all for address references to objects + not in the preceding sections. + + An idealized example of three relocatable sections follows. The +example uses the traditional section names `.text' and `.data'. Memory +addresses are on the horizontal axis. + + +-----+----+--+ + partial program # 1: |ttttt|dddd|00| + +-----+----+--+ + + text data bss + seg. seg. seg. + + +---+---+---+ + partial program # 2: |TTT|DDD|000| + +---+---+---+ + + +--+---+-----+--+----+---+-----+~~ + linked program: | |TTT|ttttt| |dddd|DDD|00000| + +--+---+-----+--+----+---+-----+~~ + + addresses: 0 ... + + +File: as.info, Node: As Sections, Next: Sub-Sections, Prev: Ld Sections, Up: Sections + +4.3 Assembler Internal Sections +=============================== + +These sections are meant only for the internal use of `as'. They have +no meaning at run-time. You do not really need to know about these +sections for most purposes; but they can be mentioned in `as' warning +messages, so it might be helpful to have an idea of their meanings to +`as'. These sections are used to permit the value of every expression +in your assembly language program to be a section-relative address. + +ASSEMBLER-INTERNAL-LOGIC-ERROR! + An internal assembler logic error has been found. This means + there is a bug in the assembler. + +expr section + The assembler stores complex expression internally as combinations + of symbols. When it needs to represent an expression as a symbol, + it puts it in the expr section. + + +File: as.info, Node: Sub-Sections, Next: bss, Prev: As Sections, Up: Sections + +4.4 Sub-Sections +================ + +Assembled bytes conventionally fall into two sections: text and data. +You may have separate groups of data in named sections that you want to +end up near to each other in the object file, even though they are not +contiguous in the assembler source. `as' allows you to use +"subsections" for this purpose. Within each section, there can be +numbered subsections with values from 0 to 8192. Objects assembled +into the same subsection go into the object file together with other +objects in the same subsection. For example, a compiler might want to +store constants in the text section, but might not want to have them +interspersed with the program being assembled. In this case, the +compiler could issue a `.text 0' before each section of code being +output, and a `.text 1' before each group of constants being output. + +Subsections are optional. If you do not use subsections, everything +goes in subsection number zero. + + Each subsection is zero-padded up to a multiple of four bytes. +(Subsections may be padded a different amount on different flavors of +`as'.) + + Subsections appear in your object file in numeric order, lowest +numbered to highest. (All this to be compatible with other people's +assemblers.) The object file contains no representation of +subsections; `ld' and other programs that manipulate object files see +no trace of them. They just see all your text subsections as a text +section, and all your data subsections as a data section. + + To specify which subsection you want subsequent statements assembled +into, use a numeric argument to specify it, in a `.text EXPRESSION' or +a `.data EXPRESSION' statement. When generating COFF output, you can +also use an extra subsection argument with arbitrary named sections: +`.section NAME, EXPRESSION'. When generating ELF output, you can also +use the `.subsection' directive (*note SubSection::) to specify a +subsection: `.subsection EXPRESSION'. EXPRESSION should be an absolute +expression (*note Expressions::). If you just say `.text' then `.text +0' is assumed. Likewise `.data' means `.data 0'. Assembly begins in +`text 0'. For instance: + .text 0 # The default subsection is text 0 anyway. + .ascii "This lives in the first text subsection. *" + .text 1 + .ascii "But this lives in the second text subsection." + .data 0 + .ascii "This lives in the data section," + .ascii "in the first data subsection." + .text 0 + .ascii "This lives in the first text section," + .ascii "immediately following the asterisk (*)." + + Each section has a "location counter" incremented by one for every +byte assembled into that section. Because subsections are merely a +convenience restricted to `as' there is no concept of a subsection +location counter. There is no way to directly manipulate a location +counter--but the `.align' directive changes it, and any label +definition captures its current value. The location counter of the +section where statements are being assembled is said to be the "active" +location counter. + + +File: as.info, Node: bss, Prev: Sub-Sections, Up: Sections + +4.5 bss Section +=============== + +The bss section is used for local common variable storage. You may +allocate address space in the bss section, but you may not dictate data +to load into it before your program executes. When your program starts +running, all the contents of the bss section are zeroed bytes. + + The `.lcomm' pseudo-op defines a symbol in the bss section; see +*Note `.lcomm': Lcomm. + + The `.comm' pseudo-op may be used to declare a common symbol, which +is another form of uninitialized symbol; see *Note `.comm': Comm. + + When assembling for a target which supports multiple sections, such +as ELF or COFF, you may switch into the `.bss' section and define +symbols as usual; see *Note `.section': Section. You may only assemble +zero values into the section. Typically the section will only contain +symbol definitions and `.skip' directives (*note `.skip': Skip.). + + +File: as.info, Node: Symbols, Next: Expressions, Prev: Sections, Up: Top + +5 Symbols +********* + +Symbols are a central concept: the programmer uses symbols to name +things, the linker uses symbols to link, and the debugger uses symbols +to debug. + + _Warning:_ `as' does not place symbols in the object file in the + same order they were declared. This may break some debuggers. + +* Menu: + +* Labels:: Labels +* Setting Symbols:: Giving Symbols Other Values +* Symbol Names:: Symbol Names +* Dot:: The Special Dot Symbol +* Symbol Attributes:: Symbol Attributes + + +File: as.info, Node: Labels, Next: Setting Symbols, Up: Symbols + +5.1 Labels +========== + +A "label" is written as a symbol immediately followed by a colon `:'. +The symbol then represents the current value of the active location +counter, and is, for example, a suitable instruction operand. You are +warned if you use the same symbol to represent two different locations: +the first definition overrides any other definitions. + + On the HPPA, the usual form for a label need not be immediately +followed by a colon, but instead must start in column zero. Only one +label may be defined on a single line. To work around this, the HPPA +version of `as' also provides a special directive `.label' for defining +labels more flexibly. + + +File: as.info, Node: Setting Symbols, Next: Symbol Names, Prev: Labels, Up: Symbols + +5.2 Giving Symbols Other Values +=============================== + +A symbol can be given an arbitrary value by writing a symbol, followed +by an equals sign `=', followed by an expression (*note Expressions::). +This is equivalent to using the `.set' directive. *Note `.set': Set. +In the same way, using a double equals sign `='`=' here represents an +equivalent of the `.eqv' directive. *Note `.eqv': Eqv. + + Blackfin does not support symbol assignment with `='. + + +File: as.info, Node: Symbol Names, Next: Dot, Prev: Setting Symbols, Up: Symbols + +5.3 Symbol Names +================ + +Symbol names begin with a letter or with one of `._'. On most +machines, you can also use `$' in symbol names; exceptions are noted in +*Note Machine Dependencies::. That character may be followed by any +string of digits, letters, dollar signs (unless otherwise noted for a +particular target machine), and underscores. + +Case of letters is significant: `foo' is a different symbol name than +`Foo'. + + Each symbol has exactly one name. Each name in an assembly language +program refers to exactly one symbol. You may use that symbol name any +number of times in a program. + +Local Symbol Names +------------------ + +A local symbol is any symbol beginning with certain local label +prefixes. By default, the local label prefix is `.L' for ELF systems or +`L' for traditional a.out systems, but each target may have its own set +of local label prefixes. On the HPPA local symbols begin with `L$'. + + Local symbols are defined and used within the assembler, but they are +normally not saved in object files. Thus, they are not visible when +debugging. You may use the `-L' option (*note Include Local Symbols: +`-L': L.) to retain the local symbols in the object files. + +Local Labels +------------ + +Local labels help compilers and programmers use names temporarily. +They create symbols which are guaranteed to be unique over the entire +scope of the input source code and which can be referred to by a simple +notation. To define a local label, write a label of the form `N:' +(where N represents any positive integer). To refer to the most recent +previous definition of that label write `Nb', using the same number as +when you defined the label. To refer to the next definition of a local +label, write `Nf'--the `b' stands for "backwards" and the `f' stands +for "forwards". + + There is no restriction on how you can use these labels, and you can +reuse them too. So that it is possible to repeatedly define the same +local label (using the same number `N'), although you can only refer to +the most recently defined local label of that number (for a backwards +reference) or the next definition of a specific local label for a +forward reference. It is also worth noting that the first 10 local +labels (`0:'...`9:') are implemented in a slightly more efficient +manner than the others. + + Here is an example: + + 1: branch 1f + 2: branch 1b + 1: branch 2f + 2: branch 1b + + Which is the equivalent of: + + label_1: branch label_3 + label_2: branch label_1 + label_3: branch label_4 + label_4: branch label_3 + + Local label names are only a notational device. They are immediately +transformed into more conventional symbol names before the assembler +uses them. The symbol names are stored in the symbol table, appear in +error messages, and are optionally emitted to the object file. The +names are constructed using these parts: + +`_local label prefix_' + All local symbols begin with the system-specific local label + prefix. Normally both `as' and `ld' forget symbols that start + with the local label prefix. These labels are used for symbols + you are never intended to see. If you use the `-L' option then + `as' retains these symbols in the object file. If you also + instruct `ld' to retain these symbols, you may use them in + debugging. + +`NUMBER' + This is the number that was used in the local label definition. + So if the label is written `55:' then the number is `55'. + +`C-B' + This unusual character is included so you do not accidentally + invent a symbol of the same name. The character has ASCII value + of `\002' (control-B). + +`_ordinal number_' + This is a serial number to keep the labels distinct. The first + definition of `0:' gets the number `1'. The 15th definition of + `0:' gets the number `15', and so on. Likewise the first + definition of `1:' gets the number `1' and its 15th definition + gets `15' as well. + + So for example, the first `1:' may be named `.L1C-B1', and the 44th +`3:' may be named `.L3C-B44'. + +Dollar Local Labels +------------------- + +`as' also supports an even more local form of local labels called +dollar labels. These labels go out of scope (i.e., they become +undefined) as soon as a non-local label is defined. Thus they remain +valid for only a small region of the input source code. Normal local +labels, by contrast, remain in scope for the entire file, or until they +are redefined by another occurrence of the same local label. + + Dollar labels are defined in exactly the same way as ordinary local +labels, except that they have a dollar sign suffix to their numeric +value, e.g., `55$:'. + + They can also be distinguished from ordinary local labels by their +transformed names which use ASCII character `\001' (control-A) as the +magic character to distinguish them from ordinary labels. For example, +the fifth definition of `6$' may be named `.L6C-A5'. + + +File: as.info, Node: Dot, Next: Symbol Attributes, Prev: Symbol Names, Up: Symbols + +5.4 The Special Dot Symbol +========================== + +The special symbol `.' refers to the current address that `as' is +assembling into. Thus, the expression `melvin: .long .' defines +`melvin' to contain its own address. Assigning a value to `.' is +treated the same as a `.org' directive. Thus, the expression `.=.+4' +is the same as saying `.space 4'. + + +File: as.info, Node: Symbol Attributes, Prev: Dot, Up: Symbols + +5.5 Symbol Attributes +===================== + +Every symbol has, as well as its name, the attributes "Value" and +"Type". Depending on output format, symbols can also have auxiliary +attributes. + + If you use a symbol without defining it, `as' assumes zero for all +these attributes, and probably won't warn you. This makes the symbol +an externally defined symbol, which is generally what you would want. + +* Menu: + +* Symbol Value:: Value +* Symbol Type:: Type + + +* a.out Symbols:: Symbol Attributes: `a.out' + +* COFF Symbols:: Symbol Attributes for COFF + +* SOM Symbols:: Symbol Attributes for SOM + + +File: as.info, Node: Symbol Value, Next: Symbol Type, Up: Symbol Attributes + +5.5.1 Value +----------- + +The value of a symbol is (usually) 32 bits. For a symbol which labels a +location in the text, data, bss or absolute sections the value is the +number of addresses from the start of that section to the label. +Naturally for text, data and bss sections the value of a symbol changes +as `ld' changes section base addresses during linking. Absolute +symbols' values do not change during linking: that is why they are +called absolute. + + The value of an undefined symbol is treated in a special way. If it +is 0 then the symbol is not defined in this assembler source file, and +`ld' tries to determine its value from other files linked into the same +program. You make this kind of symbol simply by mentioning a symbol +name without defining it. A non-zero value represents a `.comm' common +declaration. The value is how much common storage to reserve, in bytes +(addresses). The symbol refers to the first address of the allocated +storage. + + +File: as.info, Node: Symbol Type, Next: a.out Symbols, Prev: Symbol Value, Up: Symbol Attributes + +5.5.2 Type +---------- + +The type attribute of a symbol contains relocation (section) +information, any flag settings indicating that a symbol is external, and +(optionally), other information for linkers and debuggers. The exact +format depends on the object-code output format in use. + + +File: as.info, Node: a.out Symbols, Next: COFF Symbols, Prev: Symbol Type, Up: Symbol Attributes + +5.5.3 Symbol Attributes: `a.out' +-------------------------------- + +* Menu: + +* Symbol Desc:: Descriptor +* Symbol Other:: Other + + +File: as.info, Node: Symbol Desc, Next: Symbol Other, Up: a.out Symbols + +5.5.3.1 Descriptor +.................. + +This is an arbitrary 16-bit value. You may establish a symbol's +descriptor value by using a `.desc' statement (*note `.desc': Desc.). +A descriptor value means nothing to `as'. + + +File: as.info, Node: Symbol Other, Prev: Symbol Desc, Up: a.out Symbols + +5.5.3.2 Other +............. + +This is an arbitrary 8-bit value. It means nothing to `as'. + + +File: as.info, Node: COFF Symbols, Next: SOM Symbols, Prev: a.out Symbols, Up: Symbol Attributes + +5.5.4 Symbol Attributes for COFF +-------------------------------- + +The COFF format supports a multitude of auxiliary symbol attributes; +like the primary symbol attributes, they are set between `.def' and +`.endef' directives. + +5.5.4.1 Primary Attributes +.......................... + +The symbol name is set with `.def'; the value and type, respectively, +with `.val' and `.type'. + +5.5.4.2 Auxiliary Attributes +............................ + +The `as' directives `.dim', `.line', `.scl', `.size', `.tag', and +`.weak' can generate auxiliary symbol table information for COFF. + + +File: as.info, Node: SOM Symbols, Prev: COFF Symbols, Up: Symbol Attributes + +5.5.5 Symbol Attributes for SOM +------------------------------- + +The SOM format for the HPPA supports a multitude of symbol attributes +set with the `.EXPORT' and `.IMPORT' directives. + + The attributes are described in `HP9000 Series 800 Assembly Language +Reference Manual' (HP 92432-90001) under the `IMPORT' and `EXPORT' +assembler directive documentation. + + +File: as.info, Node: Expressions, Next: Pseudo Ops, Prev: Symbols, Up: Top + +6 Expressions +************* + +An "expression" specifies an address or numeric value. Whitespace may +precede and/or follow an expression. + + The result of an expression must be an absolute number, or else an +offset into a particular section. If an expression is not absolute, +and there is not enough information when `as' sees the expression to +know its section, a second pass over the source program might be +necessary to interpret the expression--but the second pass is currently +not implemented. `as' aborts with an error message in this situation. + +* Menu: + +* Empty Exprs:: Empty Expressions +* Integer Exprs:: Integer Expressions + + +File: as.info, Node: Empty Exprs, Next: Integer Exprs, Up: Expressions + +6.1 Empty Expressions +===================== + +An empty expression has no value: it is just whitespace or null. +Wherever an absolute expression is required, you may omit the +expression, and `as' assumes a value of (absolute) 0. This is +compatible with other assemblers. + + +File: as.info, Node: Integer Exprs, Prev: Empty Exprs, Up: Expressions + +6.2 Integer Expressions +======================= + +An "integer expression" is one or more _arguments_ delimited by +_operators_. + +* Menu: + +* Arguments:: Arguments +* Operators:: Operators +* Prefix Ops:: Prefix Operators +* Infix Ops:: Infix Operators + + +File: as.info, Node: Arguments, Next: Operators, Up: Integer Exprs + +6.2.1 Arguments +--------------- + +"Arguments" are symbols, numbers or subexpressions. In other contexts +arguments are sometimes called "arithmetic operands". In this manual, +to avoid confusing them with the "instruction operands" of the machine +language, we use the term "argument" to refer to parts of expressions +only, reserving the word "operand" to refer only to machine instruction +operands. + + Symbols are evaluated to yield {SECTION NNN} where SECTION is one of +text, data, bss, absolute, or undefined. NNN is a signed, 2's +complement 32 bit integer. + + Numbers are usually integers. + + A number can be a flonum or bignum. In this case, you are warned +that only the low order 32 bits are used, and `as' pretends these 32 +bits are an integer. You may write integer-manipulating instructions +that act on exotic constants, compatible with other assemblers. + + Subexpressions are a left parenthesis `(' followed by an integer +expression, followed by a right parenthesis `)'; or a prefix operator +followed by an argument. + + +File: as.info, Node: Operators, Next: Prefix Ops, Prev: Arguments, Up: Integer Exprs + +6.2.2 Operators +--------------- + +"Operators" are arithmetic functions, like `+' or `%'. Prefix +operators are followed by an argument. Infix operators appear between +their arguments. Operators may be preceded and/or followed by +whitespace. + + +File: as.info, Node: Prefix Ops, Next: Infix Ops, Prev: Operators, Up: Integer Exprs + +6.2.3 Prefix Operator +--------------------- + +`as' has the following "prefix operators". They each take one +argument, which must be absolute. + +`-' + "Negation". Two's complement negation. + +`~' + "Complementation". Bitwise not. + + +File: as.info, Node: Infix Ops, Prev: Prefix Ops, Up: Integer Exprs + +6.2.4 Infix Operators +--------------------- + +"Infix operators" take two arguments, one on either side. Operators +have precedence, but operations with equal precedence are performed left +to right. Apart from `+' or `-', both arguments must be absolute, and +the result is absolute. + + 1. Highest Precedence + + `*' + "Multiplication". + + `/' + "Division". Truncation is the same as the C operator `/' + + `%' + "Remainder". + + `<<' + "Shift Left". Same as the C operator `<<'. + + `>>' + "Shift Right". Same as the C operator `>>'. + + 2. Intermediate precedence + + `|' + "Bitwise Inclusive Or". + + `&' + "Bitwise And". + + `^' + "Bitwise Exclusive Or". + + `!' + "Bitwise Or Not". + + 3. Low Precedence + + `+' + "Addition". If either argument is absolute, the result has + the section of the other argument. You may not add together + arguments from different sections. + + `-' + "Subtraction". If the right argument is absolute, the result + has the section of the left argument. If both arguments are + in the same section, the result is absolute. You may not + subtract arguments from different sections. + + `==' + "Is Equal To" + + `<>' + `!=' + "Is Not Equal To" + + `<' + "Is Less Than" + + `>' + "Is Greater Than" + + `>=' + "Is Greater Than Or Equal To" + + `<=' + "Is Less Than Or Equal To" + + The comparison operators can be used as infix operators. A + true results has a value of -1 whereas a false result has a + value of 0. Note, these operators perform signed + comparisons. + + 4. Lowest Precedence + + `&&' + "Logical And". + + `||' + "Logical Or". + + These two logical operations can be used to combine the + results of sub expressions. Note, unlike the comparison + operators a true result returns a value of 1 but a false + results does still return 0. Also note that the logical or + operator has a slightly lower precedence than logical and. + + + In short, it's only meaningful to add or subtract the _offsets_ in an +address; you can only have a defined section in one of the two +arguments. + + +File: as.info, Node: Pseudo Ops, Next: Object Attributes, Prev: Expressions, Up: Top + +7 Assembler Directives +********************** + +All assembler directives have names that begin with a period (`.'). +The rest of the name is letters, usually in lower case. + + This chapter discusses directives that are available regardless of +the target machine configuration for the GNU assembler. Some machine +configurations provide additional directives. *Note Machine +Dependencies::. + +* Menu: + +* Abort:: `.abort' + +* ABORT (COFF):: `.ABORT' + +* Align:: `.align ABS-EXPR , ABS-EXPR' +* Altmacro:: `.altmacro' +* Ascii:: `.ascii "STRING"'... +* Asciz:: `.asciz "STRING"'... +* Balign:: `.balign ABS-EXPR , ABS-EXPR' +* Byte:: `.byte EXPRESSIONS' +* CFI directives:: `.cfi_startproc [simple]', `.cfi_endproc', etc. +* Comm:: `.comm SYMBOL , LENGTH ' +* Data:: `.data SUBSECTION' + +* Def:: `.def NAME' + +* Desc:: `.desc SYMBOL, ABS-EXPRESSION' + +* Dim:: `.dim' + +* Double:: `.double FLONUMS' +* Eject:: `.eject' +* Else:: `.else' +* Elseif:: `.elseif' +* End:: `.end' + +* Endef:: `.endef' + +* Endfunc:: `.endfunc' +* Endif:: `.endif' +* Equ:: `.equ SYMBOL, EXPRESSION' +* Equiv:: `.equiv SYMBOL, EXPRESSION' +* Eqv:: `.eqv SYMBOL, EXPRESSION' +* Err:: `.err' +* Error:: `.error STRING' +* Exitm:: `.exitm' +* Extern:: `.extern' +* Fail:: `.fail' +* File:: `.file' +* Fill:: `.fill REPEAT , SIZE , VALUE' +* Float:: `.float FLONUMS' +* Func:: `.func' +* Global:: `.global SYMBOL', `.globl SYMBOL' + +* Gnu_attribute:: `.gnu_attribute TAG,VALUE' +* Hidden:: `.hidden NAMES' + +* hword:: `.hword EXPRESSIONS' +* Ident:: `.ident' +* If:: `.if ABSOLUTE EXPRESSION' +* Incbin:: `.incbin "FILE"[,SKIP[,COUNT]]' +* Include:: `.include "FILE"' +* Int:: `.int EXPRESSIONS' + +* Internal:: `.internal NAMES' + +* Irp:: `.irp SYMBOL,VALUES'... +* Irpc:: `.irpc SYMBOL,VALUES'... +* Lcomm:: `.lcomm SYMBOL , LENGTH' +* Lflags:: `.lflags' + +* Line:: `.line LINE-NUMBER' + +* Linkonce:: `.linkonce [TYPE]' +* List:: `.list' +* Ln:: `.ln LINE-NUMBER' +* Loc:: `.loc FILENO LINENO' +* Loc_mark_labels:: `.loc_mark_labels ENABLE' + +* Local:: `.local NAMES' + +* Long:: `.long EXPRESSIONS' + +* Macro:: `.macro NAME ARGS'... +* MRI:: `.mri VAL' +* Noaltmacro:: `.noaltmacro' +* Nolist:: `.nolist' +* Octa:: `.octa BIGNUMS' +* Org:: `.org NEW-LC, FILL' +* P2align:: `.p2align ABS-EXPR, ABS-EXPR, ABS-EXPR' + +* PopSection:: `.popsection' +* Previous:: `.previous' + +* Print:: `.print STRING' + +* Protected:: `.protected NAMES' + +* Psize:: `.psize LINES, COLUMNS' +* Purgem:: `.purgem NAME' + +* PushSection:: `.pushsection NAME' + +* Quad:: `.quad BIGNUMS' +* Reloc:: `.reloc OFFSET, RELOC_NAME[, EXPRESSION]' +* Rept:: `.rept COUNT' +* Sbttl:: `.sbttl "SUBHEADING"' + +* Scl:: `.scl CLASS' + +* Section:: `.section NAME[, FLAGS]' + +* Set:: `.set SYMBOL, EXPRESSION' +* Short:: `.short EXPRESSIONS' +* Single:: `.single FLONUMS' + +* Size:: `.size [NAME , EXPRESSION]' + +* Skip:: `.skip SIZE , FILL' + +* Sleb128:: `.sleb128 EXPRESSIONS' + +* Space:: `.space SIZE , FILL' + +* Stab:: `.stabd, .stabn, .stabs' + +* String:: `.string "STR"', `.string8 "STR"', `.string16 "STR"', `.string32 "STR"', `.string64 "STR"' +* Struct:: `.struct EXPRESSION' + +* SubSection:: `.subsection' +* Symver:: `.symver NAME,NAME2@NODENAME' + + +* Tag:: `.tag STRUCTNAME' + +* Text:: `.text SUBSECTION' +* Title:: `.title "HEADING"' + +* Type:: `.type <INT | NAME , TYPE DESCRIPTION>' + +* Uleb128:: `.uleb128 EXPRESSIONS' + +* Val:: `.val ADDR' + + +* Version:: `.version "STRING"' +* VTableEntry:: `.vtable_entry TABLE, OFFSET' +* VTableInherit:: `.vtable_inherit CHILD, PARENT' + +* Warning:: `.warning STRING' +* Weak:: `.weak NAMES' +* Weakref:: `.weakref ALIAS, SYMBOL' +* Word:: `.word EXPRESSIONS' +* Deprecated:: Deprecated Directives + + +File: as.info, Node: Abort, Next: ABORT (COFF), Up: Pseudo Ops + +7.1 `.abort' +============ + +This directive stops the assembly immediately. It is for compatibility +with other assemblers. The original idea was that the assembly +language source would be piped into the assembler. If the sender of +the source quit, it could use this directive tells `as' to quit also. +One day `.abort' will not be supported. + + +File: as.info, Node: ABORT (COFF), Next: Align, Prev: Abort, Up: Pseudo Ops + +7.2 `.ABORT' (COFF) +=================== + +When producing COFF output, `as' accepts this directive as a synonym +for `.abort'. + + +File: as.info, Node: Align, Next: Altmacro, Prev: ABORT (COFF), Up: Pseudo Ops + +7.3 `.align ABS-EXPR, ABS-EXPR, ABS-EXPR' +========================================= + +Pad the location counter (in the current subsection) to a particular +storage boundary. The first expression (which must be absolute) is the +alignment required, as described below. + + The second expression (also absolute) gives the fill value to be +stored in the padding bytes. It (and the comma) may be omitted. If it +is omitted, the padding bytes are normally zero. However, on some +systems, if the section is marked as containing code and the fill value +is omitted, the space is filled with no-op instructions. + + The third expression is also absolute, and is also optional. If it +is present, it is the maximum number of bytes that should be skipped by +this alignment directive. If doing the alignment would require +skipping more bytes than the specified maximum, then the alignment is +not done at all. You can omit the fill value (the second argument) +entirely by simply using two commas after the required alignment; this +can be useful if you want the alignment to be filled with no-op +instructions when appropriate. + + The way the required alignment is specified varies from system to +system. For the arc, hppa, i386 using ELF, i860, iq2000, m68k, or32, +s390, sparc, tic4x, tic80 and xtensa, the first expression is the +alignment request in bytes. For example `.align 8' advances the +location counter until it is a multiple of 8. If the location counter +is already a multiple of 8, no change is needed. For the tic54x, the +first expression is the alignment request in words. + + For other systems, including ppc, i386 using a.out format, arm and +strongarm, it is the number of low-order zero bits the location counter +must have after advancement. For example `.align 3' advances the +location counter until it a multiple of 8. If the location counter is +already a multiple of 8, no change is needed. + + This inconsistency is due to the different behaviors of the various +native assemblers for these systems which GAS must emulate. GAS also +provides `.balign' and `.p2align' directives, described later, which +have a consistent behavior across all architectures (but are specific +to GAS). + + +File: as.info, Node: Altmacro, Next: Ascii, Prev: Align, Up: Pseudo Ops + +7.4 `.altmacro' +=============== + +Enable alternate macro mode, enabling: + +`LOCAL NAME [ , ... ]' + One additional directive, `LOCAL', is available. It is used to + generate a string replacement for each of the NAME arguments, and + replace any instances of NAME in each macro expansion. The + replacement string is unique in the assembly, and different for + each separate macro expansion. `LOCAL' allows you to write macros + that define symbols, without fear of conflict between separate + macro expansions. + +`String delimiters' + You can write strings delimited in these other ways besides + `"STRING"': + + `'STRING'' + You can delimit strings with single-quote characters. + + `<STRING>' + You can delimit strings with matching angle brackets. + +`single-character string escape' + To include any single character literally in a string (even if the + character would otherwise have some special meaning), you can + prefix the character with `!' (an exclamation mark). For example, + you can write `<4.3 !> 5.4!!>' to get the literal text `4.3 > + 5.4!'. + +`Expression results as strings' + You can write `%EXPR' to evaluate the expression EXPR and use the + result as a string. + + +File: as.info, Node: Ascii, Next: Asciz, Prev: Altmacro, Up: Pseudo Ops + +7.5 `.ascii "STRING"'... +======================== + +`.ascii' expects zero or more string literals (*note Strings::) +separated by commas. It assembles each string (with no automatic +trailing zero byte) into consecutive addresses. + + +File: as.info, Node: Asciz, Next: Balign, Prev: Ascii, Up: Pseudo Ops + +7.6 `.asciz "STRING"'... +======================== + +`.asciz' is just like `.ascii', but each string is followed by a zero +byte. The "z" in `.asciz' stands for "zero". + + +File: as.info, Node: Balign, Next: Byte, Prev: Asciz, Up: Pseudo Ops + +7.7 `.balign[wl] ABS-EXPR, ABS-EXPR, ABS-EXPR' +============================================== + +Pad the location counter (in the current subsection) to a particular +storage boundary. The first expression (which must be absolute) is the +alignment request in bytes. For example `.balign 8' advances the +location counter until it is a multiple of 8. If the location counter +is already a multiple of 8, no change is needed. + + The second expression (also absolute) gives the fill value to be +stored in the padding bytes. It (and the comma) may be omitted. If it +is omitted, the padding bytes are normally zero. However, on some +systems, if the section is marked as containing code and the fill value +is omitted, the space is filled with no-op instructions. + + The third expression is also absolute, and is also optional. If it +is present, it is the maximum number of bytes that should be skipped by +this alignment directive. If doing the alignment would require +skipping more bytes than the specified maximum, then the alignment is +not done at all. You can omit the fill value (the second argument) +entirely by simply using two commas after the required alignment; this +can be useful if you want the alignment to be filled with no-op +instructions when appropriate. + + The `.balignw' and `.balignl' directives are variants of the +`.balign' directive. The `.balignw' directive treats the fill pattern +as a two byte word value. The `.balignl' directives treats the fill +pattern as a four byte longword value. For example, `.balignw +4,0x368d' will align to a multiple of 4. If it skips two bytes, they +will be filled in with the value 0x368d (the exact placement of the +bytes depends upon the endianness of the processor). If it skips 1 or +3 bytes, the fill value is undefined. + + +File: as.info, Node: Byte, Next: CFI directives, Prev: Balign, Up: Pseudo Ops + +7.8 `.byte EXPRESSIONS' +======================= + +`.byte' expects zero or more expressions, separated by commas. Each +expression is assembled into the next byte. + + +File: as.info, Node: CFI directives, Next: Comm, Prev: Byte, Up: Pseudo Ops + +7.9 `.cfi_startproc [simple]' +============================= + +`.cfi_startproc' is used at the beginning of each function that should +have an entry in `.eh_frame'. It initializes some internal data +structures. Don't forget to close the function by `.cfi_endproc'. + +7.10 `.cfi_sections SECTION_LIST' +================================= + +`.cfi_sections' may be used to specify whether CFI directives should +emit `.eh_frame' section and/or `.debug_frame' section. If +SECTION_LIST is `.eh_frame', `.eh_frame' is emitted, if SECTION_LIST is +`.debug_frame', `.debug_frame' is emitted. To emit both use +`.eh_frame, .debug_frame'. The default if this directive is not used +is `.cfi_sections .eh_frame'. + + Unless `.cfi_startproc' is used along with parameter `simple' it +also emits some architecture dependent initial CFI instructions. + +7.11 `.cfi_endproc' +=================== + +`.cfi_endproc' is used at the end of a function where it closes its +unwind entry previously opened by `.cfi_startproc', and emits it to +`.eh_frame'. + +7.12 `.cfi_personality ENCODING [, EXP]' +======================================== + +`.cfi_personality' defines personality routine and its encoding. +ENCODING must be a constant determining how the personality should be +encoded. If it is 255 (`DW_EH_PE_omit'), second argument is not +present, otherwise second argument should be a constant or a symbol +name. When using indirect encodings, the symbol provided should be the +location where personality can be loaded from, not the personality +routine itself. The default after `.cfi_startproc' is +`.cfi_personality 0xff', no personality routine. + +7.13 `.cfi_lsda ENCODING [, EXP]' +================================= + +`.cfi_lsda' defines LSDA and its encoding. ENCODING must be a constant +determining how the LSDA should be encoded. If it is 255 +(`DW_EH_PE_omit'), second argument is not present, otherwise second +argument should be a constant or a symbol name. The default after +`.cfi_startproc' is `.cfi_lsda 0xff', no LSDA. + +7.14 `.cfi_def_cfa REGISTER, OFFSET' +==================================== + +`.cfi_def_cfa' defines a rule for computing CFA as: take address from +REGISTER and add OFFSET to it. + +7.15 `.cfi_def_cfa_register REGISTER' +===================================== + +`.cfi_def_cfa_register' modifies a rule for computing CFA. From now on +REGISTER will be used instead of the old one. Offset remains the same. + +7.16 `.cfi_def_cfa_offset OFFSET' +================================= + +`.cfi_def_cfa_offset' modifies a rule for computing CFA. Register +remains the same, but OFFSET is new. Note that it is the absolute +offset that will be added to a defined register to compute CFA address. + +7.17 `.cfi_adjust_cfa_offset OFFSET' +==================================== + +Same as `.cfi_def_cfa_offset' but OFFSET is a relative value that is +added/substracted from the previous offset. + +7.18 `.cfi_offset REGISTER, OFFSET' +=================================== + +Previous value of REGISTER is saved at offset OFFSET from CFA. + +7.19 `.cfi_rel_offset REGISTER, OFFSET' +======================================= + +Previous value of REGISTER is saved at offset OFFSET from the current +CFA register. This is transformed to `.cfi_offset' using the known +displacement of the CFA register from the CFA. This is often easier to +use, because the number will match the code it's annotating. + +7.20 `.cfi_register REGISTER1, REGISTER2' +========================================= + +Previous value of REGISTER1 is saved in register REGISTER2. + +7.21 `.cfi_restore REGISTER' +============================ + +`.cfi_restore' says that the rule for REGISTER is now the same as it +was at the beginning of the function, after all initial instruction +added by `.cfi_startproc' were executed. + +7.22 `.cfi_undefined REGISTER' +============================== + +From now on the previous value of REGISTER can't be restored anymore. + +7.23 `.cfi_same_value REGISTER' +=============================== + +Current value of REGISTER is the same like in the previous frame, i.e. +no restoration needed. + +7.24 `.cfi_remember_state', +=========================== + +First save all current rules for all registers by `.cfi_remember_state', +then totally screw them up by subsequent `.cfi_*' directives and when +everything is hopelessly bad, use `.cfi_restore_state' to restore the +previous saved state. + +7.25 `.cfi_return_column REGISTER' +================================== + +Change return column REGISTER, i.e. the return address is either +directly in REGISTER or can be accessed by rules for REGISTER. + +7.26 `.cfi_signal_frame' +======================== + +Mark current function as signal trampoline. + +7.27 `.cfi_window_save' +======================= + +SPARC register window has been saved. + +7.28 `.cfi_escape' EXPRESSION[, ...] +==================================== + +Allows the user to add arbitrary bytes to the unwind info. One might +use this to add OS-specific CFI opcodes, or generic CFI opcodes that +GAS does not yet support. + +7.29 `.cfi_val_encoded_addr REGISTER, ENCODING, LABEL' +====================================================== + +The current value of REGISTER is LABEL. The value of LABEL will be +encoded in the output file according to ENCODING; see the description +of `.cfi_personality' for details on this encoding. + + The usefulness of equating a register to a fixed label is probably +limited to the return address register. Here, it can be useful to mark +a code segment that has only one return address which is reached by a +direct branch and no copy of the return address exists in memory or +another register. + + +File: as.info, Node: Comm, Next: Data, Prev: CFI directives, Up: Pseudo Ops + +7.30 `.comm SYMBOL , LENGTH ' +============================= + +`.comm' declares a common symbol named SYMBOL. When linking, a common +symbol in one object file may be merged with a defined or common symbol +of the same name in another object file. If `ld' does not see a +definition for the symbol-just one or more common symbols-then it will +allocate LENGTH bytes of uninitialized memory. LENGTH must be an +absolute expression. If `ld' sees multiple common symbols with the +same name, and they do not all have the same size, it will allocate +space using the largest size. + + When using ELF or (as a GNU extension) PE, the `.comm' directive +takes an optional third argument. This is the desired alignment of the +symbol, specified for ELF as a byte boundary (for example, an alignment +of 16 means that the least significant 4 bits of the address should be +zero), and for PE as a power of two (for example, an alignment of 5 +means aligned to a 32-byte boundary). The alignment must be an +absolute expression, and it must be a power of two. If `ld' allocates +uninitialized memory for the common symbol, it will use the alignment +when placing the symbol. If no alignment is specified, `as' will set +the alignment to the largest power of two less than or equal to the +size of the symbol, up to a maximum of 16 on ELF, or the default +section alignment of 4 on PE(1). + + The syntax for `.comm' differs slightly on the HPPA. The syntax is +`SYMBOL .comm, LENGTH'; SYMBOL is optional. + + ---------- Footnotes ---------- + + (1) This is not the same as the executable image file alignment +controlled by `ld''s `--section-alignment' option; image file sections +in PE are aligned to multiples of 4096, which is far too large an +alignment for ordinary variables. It is rather the default alignment +for (non-debug) sections within object (`*.o') files, which are less +strictly aligned. + + +File: as.info, Node: Data, Next: Def, Prev: Comm, Up: Pseudo Ops + +7.31 `.data SUBSECTION' +======================= + +`.data' tells `as' to assemble the following statements onto the end of +the data subsection numbered SUBSECTION (which is an absolute +expression). If SUBSECTION is omitted, it defaults to zero. + + +File: as.info, Node: Def, Next: Desc, Prev: Data, Up: Pseudo Ops + +7.32 `.def NAME' +================ + +Begin defining debugging information for a symbol NAME; the definition +extends until the `.endef' directive is encountered. + + +File: as.info, Node: Desc, Next: Dim, Prev: Def, Up: Pseudo Ops + +7.33 `.desc SYMBOL, ABS-EXPRESSION' +=================================== + +This directive sets the descriptor of the symbol (*note Symbol +Attributes::) to the low 16 bits of an absolute expression. + + The `.desc' directive is not available when `as' is configured for +COFF output; it is only for `a.out' or `b.out' object format. For the +sake of compatibility, `as' accepts it, but produces no output, when +configured for COFF. + + +File: as.info, Node: Dim, Next: Double, Prev: Desc, Up: Pseudo Ops + +7.34 `.dim' +=========== + +This directive is generated by compilers to include auxiliary debugging +information in the symbol table. It is only permitted inside +`.def'/`.endef' pairs. + + +File: as.info, Node: Double, Next: Eject, Prev: Dim, Up: Pseudo Ops + +7.35 `.double FLONUMS' +====================== + +`.double' expects zero or more flonums, separated by commas. It +assembles floating point numbers. The exact kind of floating point +numbers emitted depends on how `as' is configured. *Note Machine +Dependencies::. + + +File: as.info, Node: Eject, Next: Else, Prev: Double, Up: Pseudo Ops + +7.36 `.eject' +============= + +Force a page break at this point, when generating assembly listings. + + +File: as.info, Node: Else, Next: Elseif, Prev: Eject, Up: Pseudo Ops + +7.37 `.else' +============ + +`.else' is part of the `as' support for conditional assembly; see *Note +`.if': If. It marks the beginning of a section of code to be assembled +if the condition for the preceding `.if' was false. + + +File: as.info, Node: Elseif, Next: End, Prev: Else, Up: Pseudo Ops + +7.38 `.elseif' +============== + +`.elseif' is part of the `as' support for conditional assembly; see +*Note `.if': If. It is shorthand for beginning a new `.if' block that +would otherwise fill the entire `.else' section. + + +File: as.info, Node: End, Next: Endef, Prev: Elseif, Up: Pseudo Ops + +7.39 `.end' +=========== + +`.end' marks the end of the assembly file. `as' does not process +anything in the file past the `.end' directive. + + +File: as.info, Node: Endef, Next: Endfunc, Prev: End, Up: Pseudo Ops + +7.40 `.endef' +============= + +This directive flags the end of a symbol definition begun with `.def'. + + +File: as.info, Node: Endfunc, Next: Endif, Prev: Endef, Up: Pseudo Ops + +7.41 `.endfunc' +=============== + +`.endfunc' marks the end of a function specified with `.func'. + + +File: as.info, Node: Endif, Next: Equ, Prev: Endfunc, Up: Pseudo Ops + +7.42 `.endif' +============= + +`.endif' is part of the `as' support for conditional assembly; it marks +the end of a block of code that is only assembled conditionally. *Note +`.if': If. + + +File: as.info, Node: Equ, Next: Equiv, Prev: Endif, Up: Pseudo Ops + +7.43 `.equ SYMBOL, EXPRESSION' +============================== + +This directive sets the value of SYMBOL to EXPRESSION. It is +synonymous with `.set'; see *Note `.set': Set. + + The syntax for `equ' on the HPPA is `SYMBOL .equ EXPRESSION'. + + The syntax for `equ' on the Z80 is `SYMBOL equ EXPRESSION'. On the +Z80 it is an eror if SYMBOL is already defined, but the symbol is not +protected from later redefinition. Compare *Note Equiv::. + + +File: as.info, Node: Equiv, Next: Eqv, Prev: Equ, Up: Pseudo Ops + +7.44 `.equiv SYMBOL, EXPRESSION' +================================ + +The `.equiv' directive is like `.equ' and `.set', except that the +assembler will signal an error if SYMBOL is already defined. Note a +symbol which has been referenced but not actually defined is considered +to be undefined. + + Except for the contents of the error message, this is roughly +equivalent to + .ifdef SYM + .err + .endif + .equ SYM,VAL + plus it protects the symbol from later redefinition. + + +File: as.info, Node: Eqv, Next: Err, Prev: Equiv, Up: Pseudo Ops + +7.45 `.eqv SYMBOL, EXPRESSION' +============================== + +The `.eqv' directive is like `.equiv', but no attempt is made to +evaluate the expression or any part of it immediately. Instead each +time the resulting symbol is used in an expression, a snapshot of its +current value is taken. + + +File: as.info, Node: Err, Next: Error, Prev: Eqv, Up: Pseudo Ops + +7.46 `.err' +=========== + +If `as' assembles a `.err' directive, it will print an error message +and, unless the `-Z' option was used, it will not generate an object +file. This can be used to signal an error in conditionally compiled +code. + + +File: as.info, Node: Error, Next: Exitm, Prev: Err, Up: Pseudo Ops + +7.47 `.error "STRING"' +====================== + +Similarly to `.err', this directive emits an error, but you can specify +a string that will be emitted as the error message. If you don't +specify the message, it defaults to `".error directive invoked in +source file"'. *Note Error and Warning Messages: Errors. + + .error "This code has not been assembled and tested." + + +File: as.info, Node: Exitm, Next: Extern, Prev: Error, Up: Pseudo Ops + +7.48 `.exitm' +============= + +Exit early from the current macro definition. *Note Macro::. + + +File: as.info, Node: Extern, Next: Fail, Prev: Exitm, Up: Pseudo Ops + +7.49 `.extern' +============== + +`.extern' is accepted in the source program--for compatibility with +other assemblers--but it is ignored. `as' treats all undefined symbols +as external. + + +File: as.info, Node: Fail, Next: File, Prev: Extern, Up: Pseudo Ops + +7.50 `.fail EXPRESSION' +======================= + +Generates an error or a warning. If the value of the EXPRESSION is 500 +or more, `as' will print a warning message. If the value is less than +500, `as' will print an error message. The message will include the +value of EXPRESSION. This can occasionally be useful inside complex +nested macros or conditional assembly. + + +File: as.info, Node: File, Next: Fill, Prev: Fail, Up: Pseudo Ops + +7.51 `.file' +============ + +There are two different versions of the `.file' directive. Targets +that support DWARF2 line number information use the DWARF2 version of +`.file'. Other targets use the default version. + +Default Version +--------------- + +This version of the `.file' directive tells `as' that we are about to +start a new logical file. The syntax is: + + .file STRING + + STRING is the new file name. In general, the filename is recognized +whether or not it is surrounded by quotes `"'; but if you wish to +specify an empty file name, you must give the quotes-`""'. This +statement may go away in future: it is only recognized to be compatible +with old `as' programs. + +DWARF2 Version +-------------- + +When emitting DWARF2 line number information, `.file' assigns filenames +to the `.debug_line' file name table. The syntax is: + + .file FILENO FILENAME + + The FILENO operand should be a unique positive integer to use as the +index of the entry in the table. The FILENAME operand is a C string +literal. + + The detail of filename indices is exposed to the user because the +filename table is shared with the `.debug_info' section of the DWARF2 +debugging information, and thus the user must know the exact indices +that table entries will have. + + +File: as.info, Node: Fill, Next: Float, Prev: File, Up: Pseudo Ops + +7.52 `.fill REPEAT , SIZE , VALUE' +================================== + +REPEAT, SIZE and VALUE are absolute expressions. This emits REPEAT +copies of SIZE bytes. REPEAT may be zero or more. SIZE may be zero or +more, but if it is more than 8, then it is deemed to have the value 8, +compatible with other people's assemblers. The contents of each REPEAT +bytes is taken from an 8-byte number. The highest order 4 bytes are +zero. The lowest order 4 bytes are VALUE rendered in the byte-order of +an integer on the computer `as' is assembling for. Each SIZE bytes in +a repetition is taken from the lowest order SIZE bytes of this number. +Again, this bizarre behavior is compatible with other people's +assemblers. + + SIZE and VALUE are optional. If the second comma and VALUE are +absent, VALUE is assumed zero. If the first comma and following tokens +are absent, SIZE is assumed to be 1. + + +File: as.info, Node: Float, Next: Func, Prev: Fill, Up: Pseudo Ops + +7.53 `.float FLONUMS' +===================== + +This directive assembles zero or more flonums, separated by commas. It +has the same effect as `.single'. The exact kind of floating point +numbers emitted depends on how `as' is configured. *Note Machine +Dependencies::. + + +File: as.info, Node: Func, Next: Global, Prev: Float, Up: Pseudo Ops + +7.54 `.func NAME[,LABEL]' +========================= + +`.func' emits debugging information to denote function NAME, and is +ignored unless the file is assembled with debugging enabled. Only +`--gstabs[+]' is currently supported. LABEL is the entry point of the +function and if omitted NAME prepended with the `leading char' is used. +`leading char' is usually `_' or nothing, depending on the target. All +functions are currently defined to have `void' return type. The +function must be terminated with `.endfunc'. + + +File: as.info, Node: Global, Next: Gnu_attribute, Prev: Func, Up: Pseudo Ops + +7.55 `.global SYMBOL', `.globl SYMBOL' +====================================== + +`.global' makes the symbol visible to `ld'. If you define SYMBOL in +your partial program, its value is made available to other partial +programs that are linked with it. Otherwise, SYMBOL takes its +attributes from a symbol of the same name from another file linked into +the same program. + + Both spellings (`.globl' and `.global') are accepted, for +compatibility with other assemblers. + + On the HPPA, `.global' is not always enough to make it accessible to +other partial programs. You may need the HPPA-only `.EXPORT' directive +as well. *Note HPPA Assembler Directives: HPPA Directives. + + +File: as.info, Node: Gnu_attribute, Next: Hidden, Prev: Global, Up: Pseudo Ops + +7.56 `.gnu_attribute TAG,VALUE' +=============================== + +Record a GNU object attribute for this file. *Note Object Attributes::. + + +File: as.info, Node: Hidden, Next: hword, Prev: Gnu_attribute, Up: Pseudo Ops + +7.57 `.hidden NAMES' +==================== + +This is one of the ELF visibility directives. The other two are +`.internal' (*note `.internal': Internal.) and `.protected' (*note +`.protected': Protected.). + + This directive overrides the named symbols default visibility (which +is set by their binding: local, global or weak). The directive sets +the visibility to `hidden' which means that the symbols are not visible +to other components. Such symbols are always considered to be +`protected' as well. + + +File: as.info, Node: hword, Next: Ident, Prev: Hidden, Up: Pseudo Ops + +7.58 `.hword EXPRESSIONS' +========================= + +This expects zero or more EXPRESSIONS, and emits a 16 bit number for +each. + + This directive is a synonym for `.short'; depending on the target +architecture, it may also be a synonym for `.word'. + + +File: as.info, Node: Ident, Next: If, Prev: hword, Up: Pseudo Ops + +7.59 `.ident' +============= + +This directive is used by some assemblers to place tags in object +files. The behavior of this directive varies depending on the target. +When using the a.out object file format, `as' simply accepts the +directive for source-file compatibility with existing assemblers, but +does not emit anything for it. When using COFF, comments are emitted +to the `.comment' or `.rdata' section, depending on the target. When +using ELF, comments are emitted to the `.comment' section. + + +File: as.info, Node: If, Next: Incbin, Prev: Ident, Up: Pseudo Ops + +7.60 `.if ABSOLUTE EXPRESSION' +============================== + +`.if' marks the beginning of a section of code which is only considered +part of the source program being assembled if the argument (which must +be an ABSOLUTE EXPRESSION) is non-zero. The end of the conditional +section of code must be marked by `.endif' (*note `.endif': Endif.); +optionally, you may include code for the alternative condition, flagged +by `.else' (*note `.else': Else.). If you have several conditions to +check, `.elseif' may be used to avoid nesting blocks if/else within +each subsequent `.else' block. + + The following variants of `.if' are also supported: +`.ifdef SYMBOL' + Assembles the following section of code if the specified SYMBOL + has been defined. Note a symbol which has been referenced but not + yet defined is considered to be undefined. + +`.ifb TEXT' + Assembles the following section of code if the operand is blank + (empty). + +`.ifc STRING1,STRING2' + Assembles the following section of code if the two strings are the + same. The strings may be optionally quoted with single quotes. + If they are not quoted, the first string stops at the first comma, + and the second string stops at the end of the line. Strings which + contain whitespace should be quoted. The string comparison is + case sensitive. + +`.ifeq ABSOLUTE EXPRESSION' + Assembles the following section of code if the argument is zero. + +`.ifeqs STRING1,STRING2' + Another form of `.ifc'. The strings must be quoted using double + quotes. + +`.ifge ABSOLUTE EXPRESSION' + Assembles the following section of code if the argument is greater + than or equal to zero. + +`.ifgt ABSOLUTE EXPRESSION' + Assembles the following section of code if the argument is greater + than zero. + +`.ifle ABSOLUTE EXPRESSION' + Assembles the following section of code if the argument is less + than or equal to zero. + +`.iflt ABSOLUTE EXPRESSION' + Assembles the following section of code if the argument is less + than zero. + +`.ifnb TEXT' + Like `.ifb', but the sense of the test is reversed: this assembles + the following section of code if the operand is non-blank + (non-empty). + +`.ifnc STRING1,STRING2.' + Like `.ifc', but the sense of the test is reversed: this assembles + the following section of code if the two strings are not the same. + +`.ifndef SYMBOL' +`.ifnotdef SYMBOL' + Assembles the following section of code if the specified SYMBOL + has not been defined. Both spelling variants are equivalent. + Note a symbol which has been referenced but not yet defined is + considered to be undefined. + +`.ifne ABSOLUTE EXPRESSION' + Assembles the following section of code if the argument is not + equal to zero (in other words, this is equivalent to `.if'). + +`.ifnes STRING1,STRING2' + Like `.ifeqs', but the sense of the test is reversed: this + assembles the following section of code if the two strings are not + the same. + + +File: as.info, Node: Incbin, Next: Include, Prev: If, Up: Pseudo Ops + +7.61 `.incbin "FILE"[,SKIP[,COUNT]]' +==================================== + +The `incbin' directive includes FILE verbatim at the current location. +You can control the search paths used with the `-I' command-line option +(*note Command-Line Options: Invoking.). Quotation marks are required +around FILE. + + The SKIP argument skips a number of bytes from the start of the +FILE. The COUNT argument indicates the maximum number of bytes to +read. Note that the data is not aligned in any way, so it is the user's +responsibility to make sure that proper alignment is provided both +before and after the `incbin' directive. + + +File: as.info, Node: Include, Next: Int, Prev: Incbin, Up: Pseudo Ops + +7.62 `.include "FILE"' +====================== + +This directive provides a way to include supporting files at specified +points in your source program. The code from FILE is assembled as if +it followed the point of the `.include'; when the end of the included +file is reached, assembly of the original file continues. You can +control the search paths used with the `-I' command-line option (*note +Command-Line Options: Invoking.). Quotation marks are required around +FILE. + + +File: as.info, Node: Int, Next: Internal, Prev: Include, Up: Pseudo Ops + +7.63 `.int EXPRESSIONS' +======================= + +Expect zero or more EXPRESSIONS, of any section, separated by commas. +For each expression, emit a number that, at run time, is the value of +that expression. The byte order and bit size of the number depends on +what kind of target the assembly is for. + + +File: as.info, Node: Internal, Next: Irp, Prev: Int, Up: Pseudo Ops + +7.64 `.internal NAMES' +====================== + +This is one of the ELF visibility directives. The other two are +`.hidden' (*note `.hidden': Hidden.) and `.protected' (*note +`.protected': Protected.). + + This directive overrides the named symbols default visibility (which +is set by their binding: local, global or weak). The directive sets +the visibility to `internal' which means that the symbols are +considered to be `hidden' (i.e., not visible to other components), and +that some extra, processor specific processing must also be performed +upon the symbols as well. + + +File: as.info, Node: Irp, Next: Irpc, Prev: Internal, Up: Pseudo Ops + +7.65 `.irp SYMBOL,VALUES'... +============================ + +Evaluate a sequence of statements assigning different values to SYMBOL. +The sequence of statements starts at the `.irp' directive, and is +terminated by an `.endr' directive. For each VALUE, SYMBOL is set to +VALUE, and the sequence of statements is assembled. If no VALUE is +listed, the sequence of statements is assembled once, with SYMBOL set +to the null string. To refer to SYMBOL within the sequence of +statements, use \SYMBOL. + + For example, assembling + + .irp param,1,2,3 + move d\param,sp@- + .endr + + is equivalent to assembling + + move d1,sp@- + move d2,sp@- + move d3,sp@- + + For some caveats with the spelling of SYMBOL, see also *Note Macro::. + + +File: as.info, Node: Irpc, Next: Lcomm, Prev: Irp, Up: Pseudo Ops + +7.66 `.irpc SYMBOL,VALUES'... +============================= + +Evaluate a sequence of statements assigning different values to SYMBOL. +The sequence of statements starts at the `.irpc' directive, and is +terminated by an `.endr' directive. For each character in VALUE, +SYMBOL is set to the character, and the sequence of statements is +assembled. If no VALUE is listed, the sequence of statements is +assembled once, with SYMBOL set to the null string. To refer to SYMBOL +within the sequence of statements, use \SYMBOL. + + For example, assembling + + .irpc param,123 + move d\param,sp@- + .endr + + is equivalent to assembling + + move d1,sp@- + move d2,sp@- + move d3,sp@- + + For some caveats with the spelling of SYMBOL, see also the discussion +at *Note Macro::. + + +File: as.info, Node: Lcomm, Next: Lflags, Prev: Irpc, Up: Pseudo Ops + +7.67 `.lcomm SYMBOL , LENGTH' +============================= + +Reserve LENGTH (an absolute expression) bytes for a local common +denoted by SYMBOL. The section and value of SYMBOL are those of the +new local common. The addresses are allocated in the bss section, so +that at run-time the bytes start off zeroed. SYMBOL is not declared +global (*note `.global': Global.), so is normally not visible to `ld'. + + Some targets permit a third argument to be used with `.lcomm'. This +argument specifies the desired alignment of the symbol in the bss +section. + + The syntax for `.lcomm' differs slightly on the HPPA. The syntax is +`SYMBOL .lcomm, LENGTH'; SYMBOL is optional. + + +File: as.info, Node: Lflags, Next: Line, Prev: Lcomm, Up: Pseudo Ops + +7.68 `.lflags' +============== + +`as' accepts this directive, for compatibility with other assemblers, +but ignores it. + + +File: as.info, Node: Line, Next: Linkonce, Prev: Lflags, Up: Pseudo Ops + +7.69 `.line LINE-NUMBER' +======================== + +Change the logical line number. LINE-NUMBER must be an absolute +expression. The next line has that logical line number. Therefore any +other statements on the current line (after a statement separator +character) are reported as on logical line number LINE-NUMBER - 1. One +day `as' will no longer support this directive: it is recognized only +for compatibility with existing assembler programs. + +Even though this is a directive associated with the `a.out' or `b.out' +object-code formats, `as' still recognizes it when producing COFF +output, and treats `.line' as though it were the COFF `.ln' _if_ it is +found outside a `.def'/`.endef' pair. + + Inside a `.def', `.line' is, instead, one of the directives used by +compilers to generate auxiliary symbol information for debugging. + + +File: as.info, Node: Linkonce, Next: List, Prev: Line, Up: Pseudo Ops + +7.70 `.linkonce [TYPE]' +======================= + +Mark the current section so that the linker only includes a single copy +of it. This may be used to include the same section in several +different object files, but ensure that the linker will only include it +once in the final output file. The `.linkonce' pseudo-op must be used +for each instance of the section. Duplicate sections are detected +based on the section name, so it should be unique. + + This directive is only supported by a few object file formats; as of +this writing, the only object file format which supports it is the +Portable Executable format used on Windows NT. + + The TYPE argument is optional. If specified, it must be one of the +following strings. For example: + .linkonce same_size + Not all types may be supported on all object file formats. + +`discard' + Silently discard duplicate sections. This is the default. + +`one_only' + Warn if there are duplicate sections, but still keep only one copy. + +`same_size' + Warn if any of the duplicates have different sizes. + +`same_contents' + Warn if any of the duplicates do not have exactly the same + contents. + + +File: as.info, Node: List, Next: Ln, Prev: Linkonce, Up: Pseudo Ops + +7.71 `.list' +============ + +Control (in conjunction with the `.nolist' directive) whether or not +assembly listings are generated. These two directives maintain an +internal counter (which is zero initially). `.list' increments the +counter, and `.nolist' decrements it. Assembly listings are generated +whenever the counter is greater than zero. + + By default, listings are disabled. When you enable them (with the +`-a' command line option; *note Command-Line Options: Invoking.), the +initial value of the listing counter is one. + + +File: as.info, Node: Ln, Next: Loc, Prev: List, Up: Pseudo Ops + +7.72 `.ln LINE-NUMBER' +====================== + +`.ln' is a synonym for `.line'. + + +File: as.info, Node: Loc, Next: Loc_mark_labels, Prev: Ln, Up: Pseudo Ops + +7.73 `.loc FILENO LINENO [COLUMN] [OPTIONS]' +============================================ + +When emitting DWARF2 line number information, the `.loc' directive will +add a row to the `.debug_line' line number matrix corresponding to the +immediately following assembly instruction. The FILENO, LINENO, and +optional COLUMN arguments will be applied to the `.debug_line' state +machine before the row is added. + + The OPTIONS are a sequence of the following tokens in any order: + +`basic_block' + This option will set the `basic_block' register in the + `.debug_line' state machine to `true'. + +`prologue_end' + This option will set the `prologue_end' register in the + `.debug_line' state machine to `true'. + +`epilogue_begin' + This option will set the `epilogue_begin' register in the + `.debug_line' state machine to `true'. + +`is_stmt VALUE' + This option will set the `is_stmt' register in the `.debug_line' + state machine to `value', which must be either 0 or 1. + +`isa VALUE' + This directive will set the `isa' register in the `.debug_line' + state machine to VALUE, which must be an unsigned integer. + +`discriminator VALUE' + This directive will set the `discriminator' register in the + `.debug_line' state machine to VALUE, which must be an unsigned + integer. + + + +File: as.info, Node: Loc_mark_labels, Next: Local, Prev: Loc, Up: Pseudo Ops + +7.74 `.loc_mark_labels ENABLE' +============================== + +When emitting DWARF2 line number information, the `.loc_mark_labels' +directive makes the assembler emit an entry to the `.debug_line' line +number matrix with the `basic_block' register in the state machine set +whenever a code label is seen. The ENABLE argument should be either 1 +or 0, to enable or disable this function respectively. + + +File: as.info, Node: Local, Next: Long, Prev: Loc_mark_labels, Up: Pseudo Ops + +7.75 `.local NAMES' +=================== + +This directive, which is available for ELF targets, marks each symbol in +the comma-separated list of `names' as a local symbol so that it will +not be externally visible. If the symbols do not already exist, they +will be created. + + For targets where the `.lcomm' directive (*note Lcomm::) does not +accept an alignment argument, which is the case for most ELF targets, +the `.local' directive can be used in combination with `.comm' (*note +Comm::) to define aligned local common data. + + +File: as.info, Node: Long, Next: Macro, Prev: Local, Up: Pseudo Ops + +7.76 `.long EXPRESSIONS' +======================== + +`.long' is the same as `.int'. *Note `.int': Int. + + +File: as.info, Node: Macro, Next: MRI, Prev: Long, Up: Pseudo Ops + +7.77 `.macro' +============= + +The commands `.macro' and `.endm' allow you to define macros that +generate assembly output. For example, this definition specifies a +macro `sum' that puts a sequence of numbers into memory: + + .macro sum from=0, to=5 + .long \from + .if \to-\from + sum "(\from+1)",\to + .endif + .endm + +With that definition, `SUM 0,5' is equivalent to this assembly input: + + .long 0 + .long 1 + .long 2 + .long 3 + .long 4 + .long 5 + +`.macro MACNAME' +`.macro MACNAME MACARGS ...' + Begin the definition of a macro called MACNAME. If your macro + definition requires arguments, specify their names after the macro + name, separated by commas or spaces. You can qualify the macro + argument to indicate whether all invocations must specify a + non-blank value (through `:`req''), or whether it takes all of the + remaining arguments (through `:`vararg''). You can supply a + default value for any macro argument by following the name with + `=DEFLT'. You cannot define two macros with the same MACNAME + unless it has been subject to the `.purgem' directive (*note + Purgem::) between the two definitions. For example, these are all + valid `.macro' statements: + + `.macro comm' + Begin the definition of a macro called `comm', which takes no + arguments. + + `.macro plus1 p, p1' + `.macro plus1 p p1' + Either statement begins the definition of a macro called + `plus1', which takes two arguments; within the macro + definition, write `\p' or `\p1' to evaluate the arguments. + + `.macro reserve_str p1=0 p2' + Begin the definition of a macro called `reserve_str', with two + arguments. The first argument has a default value, but not + the second. After the definition is complete, you can call + the macro either as `reserve_str A,B' (with `\p1' evaluating + to A and `\p2' evaluating to B), or as `reserve_str ,B' (with + `\p1' evaluating as the default, in this case `0', and `\p2' + evaluating to B). + + `.macro m p1:req, p2=0, p3:vararg' + Begin the definition of a macro called `m', with at least + three arguments. The first argument must always have a value + specified, but not the second, which instead has a default + value. The third formal will get assigned all remaining + arguments specified at invocation time. + + When you call a macro, you can specify the argument values + either by position, or by keyword. For example, `sum 9,17' + is equivalent to `sum to=17, from=9'. + + + Note that since each of the MACARGS can be an identifier exactly + as any other one permitted by the target architecture, there may be + occasional problems if the target hand-crafts special meanings to + certain characters when they occur in a special position. For + example, if the colon (`:') is generally permitted to be part of a + symbol name, but the architecture specific code special-cases it + when occurring as the final character of a symbol (to denote a + label), then the macro parameter replacement code will have no way + of knowing that and consider the whole construct (including the + colon) an identifier, and check only this identifier for being the + subject to parameter substitution. So for example this macro + definition: + + .macro label l + \l: + .endm + + might not work as expected. Invoking `label foo' might not create + a label called `foo' but instead just insert the text `\l:' into + the assembler source, probably generating an error about an + unrecognised identifier. + + Similarly problems might occur with the period character (`.') + which is often allowed inside opcode names (and hence identifier + names). So for example constructing a macro to build an opcode + from a base name and a length specifier like this: + + .macro opcode base length + \base.\length + .endm + + and invoking it as `opcode store l' will not create a `store.l' + instruction but instead generate some kind of error as the + assembler tries to interpret the text `\base.\length'. + + There are several possible ways around this problem: + + `Insert white space' + If it is possible to use white space characters then this is + the simplest solution. eg: + + .macro label l + \l : + .endm + + `Use `\()'' + The string `\()' can be used to separate the end of a macro + argument from the following text. eg: + + .macro opcode base length + \base\().\length + .endm + + `Use the alternate macro syntax mode' + In the alternative macro syntax mode the ampersand character + (`&') can be used as a separator. eg: + + .altmacro + .macro label l + l&: + .endm + + Note: this problem of correctly identifying string parameters to + pseudo ops also applies to the identifiers used in `.irp' (*note + Irp::) and `.irpc' (*note Irpc::) as well. + +`.endm' + Mark the end of a macro definition. + +`.exitm' + Exit early from the current macro definition. + +`\@' + `as' maintains a counter of how many macros it has executed in + this pseudo-variable; you can copy that number to your output with + `\@', but _only within a macro definition_. + +`LOCAL NAME [ , ... ]' + _Warning: `LOCAL' is only available if you select "alternate macro + syntax" with `--alternate' or `.altmacro'._ *Note `.altmacro': + Altmacro. + + +File: as.info, Node: MRI, Next: Noaltmacro, Prev: Macro, Up: Pseudo Ops + +7.78 `.mri VAL' +=============== + +If VAL is non-zero, this tells `as' to enter MRI mode. If VAL is zero, +this tells `as' to exit MRI mode. This change affects code assembled +until the next `.mri' directive, or until the end of the file. *Note +MRI mode: M. + + +File: as.info, Node: Noaltmacro, Next: Nolist, Prev: MRI, Up: Pseudo Ops + +7.79 `.noaltmacro' +================== + +Disable alternate macro mode. *Note Altmacro::. + + +File: as.info, Node: Nolist, Next: Octa, Prev: Noaltmacro, Up: Pseudo Ops + +7.80 `.nolist' +============== + +Control (in conjunction with the `.list' directive) whether or not +assembly listings are generated. These two directives maintain an +internal counter (which is zero initially). `.list' increments the +counter, and `.nolist' decrements it. Assembly listings are generated +whenever the counter is greater than zero. + + +File: as.info, Node: Octa, Next: Org, Prev: Nolist, Up: Pseudo Ops + +7.81 `.octa BIGNUMS' +==================== + +This directive expects zero or more bignums, separated by commas. For +each bignum, it emits a 16-byte integer. + + The term "octa" comes from contexts in which a "word" is two bytes; +hence _octa_-word for 16 bytes. + + +File: as.info, Node: Org, Next: P2align, Prev: Octa, Up: Pseudo Ops + +7.82 `.org NEW-LC , FILL' +========================= + +Advance the location counter of the current section to NEW-LC. NEW-LC +is either an absolute expression or an expression with the same section +as the current subsection. That is, you can't use `.org' to cross +sections: if NEW-LC has the wrong section, the `.org' directive is +ignored. To be compatible with former assemblers, if the section of +NEW-LC is absolute, `as' issues a warning, then pretends the section of +NEW-LC is the same as the current subsection. + + `.org' may only increase the location counter, or leave it +unchanged; you cannot use `.org' to move the location counter backwards. + + Because `as' tries to assemble programs in one pass, NEW-LC may not +be undefined. If you really detest this restriction we eagerly await a +chance to share your improved assembler. + + Beware that the origin is relative to the start of the section, not +to the start of the subsection. This is compatible with other people's +assemblers. + + When the location counter (of the current subsection) is advanced, +the intervening bytes are filled with FILL which should be an absolute +expression. If the comma and FILL are omitted, FILL defaults to zero. + + +File: as.info, Node: P2align, Next: PopSection, Prev: Org, Up: Pseudo Ops + +7.83 `.p2align[wl] ABS-EXPR, ABS-EXPR, ABS-EXPR' +================================================ + +Pad the location counter (in the current subsection) to a particular +storage boundary. The first expression (which must be absolute) is the +number of low-order zero bits the location counter must have after +advancement. For example `.p2align 3' advances the location counter +until it a multiple of 8. If the location counter is already a +multiple of 8, no change is needed. + + The second expression (also absolute) gives the fill value to be +stored in the padding bytes. It (and the comma) may be omitted. If it +is omitted, the padding bytes are normally zero. However, on some +systems, if the section is marked as containing code and the fill value +is omitted, the space is filled with no-op instructions. + + The third expression is also absolute, and is also optional. If it +is present, it is the maximum number of bytes that should be skipped by +this alignment directive. If doing the alignment would require +skipping more bytes than the specified maximum, then the alignment is +not done at all. You can omit the fill value (the second argument) +entirely by simply using two commas after the required alignment; this +can be useful if you want the alignment to be filled with no-op +instructions when appropriate. + + The `.p2alignw' and `.p2alignl' directives are variants of the +`.p2align' directive. The `.p2alignw' directive treats the fill +pattern as a two byte word value. The `.p2alignl' directives treats the +fill pattern as a four byte longword value. For example, `.p2alignw +2,0x368d' will align to a multiple of 4. If it skips two bytes, they +will be filled in with the value 0x368d (the exact placement of the +bytes depends upon the endianness of the processor). If it skips 1 or +3 bytes, the fill value is undefined. + + +File: as.info, Node: PopSection, Next: Previous, Prev: P2align, Up: Pseudo Ops + +7.84 `.popsection' +================== + +This is one of the ELF section stack manipulation directives. The +others are `.section' (*note Section::), `.subsection' (*note +SubSection::), `.pushsection' (*note PushSection::), and `.previous' +(*note Previous::). + + This directive replaces the current section (and subsection) with +the top section (and subsection) on the section stack. This section is +popped off the stack. + + +File: as.info, Node: Previous, Next: Print, Prev: PopSection, Up: Pseudo Ops + +7.85 `.previous' +================ + +This is one of the ELF section stack manipulation directives. The +others are `.section' (*note Section::), `.subsection' (*note +SubSection::), `.pushsection' (*note PushSection::), and `.popsection' +(*note PopSection::). + + This directive swaps the current section (and subsection) with most +recently referenced section/subsection pair prior to this one. Multiple +`.previous' directives in a row will flip between two sections (and +their subsections). For example: + + .section A + .subsection 1 + .word 0x1234 + .subsection 2 + .word 0x5678 + .previous + .word 0x9abc + + Will place 0x1234 and 0x9abc into subsection 1 and 0x5678 into +subsection 2 of section A. Whilst: + + .section A + .subsection 1 + # Now in section A subsection 1 + .word 0x1234 + .section B + .subsection 0 + # Now in section B subsection 0 + .word 0x5678 + .subsection 1 + # Now in section B subsection 1 + .word 0x9abc + .previous + # Now in section B subsection 0 + .word 0xdef0 + + Will place 0x1234 into section A, 0x5678 and 0xdef0 into subsection +0 of section B and 0x9abc into subsection 1 of section B. + + In terms of the section stack, this directive swaps the current +section with the top section on the section stack. + + +File: as.info, Node: Print, Next: Protected, Prev: Previous, Up: Pseudo Ops + +7.86 `.print STRING' +==================== + +`as' will print STRING on the standard output during assembly. You +must put STRING in double quotes. + + +File: as.info, Node: Protected, Next: Psize, Prev: Print, Up: Pseudo Ops + +7.87 `.protected NAMES' +======================= + +This is one of the ELF visibility directives. The other two are +`.hidden' (*note Hidden::) and `.internal' (*note Internal::). + + This directive overrides the named symbols default visibility (which +is set by their binding: local, global or weak). The directive sets +the visibility to `protected' which means that any references to the +symbols from within the components that defines them must be resolved +to the definition in that component, even if a definition in another +component would normally preempt this. + + +File: as.info, Node: Psize, Next: Purgem, Prev: Protected, Up: Pseudo Ops + +7.88 `.psize LINES , COLUMNS' +============================= + +Use this directive to declare the number of lines--and, optionally, the +number of columns--to use for each page, when generating listings. + + If you do not use `.psize', listings use a default line-count of 60. +You may omit the comma and COLUMNS specification; the default width is +200 columns. + + `as' generates formfeeds whenever the specified number of lines is +exceeded (or whenever you explicitly request one, using `.eject'). + + If you specify LINES as `0', no formfeeds are generated save those +explicitly specified with `.eject'. + + +File: as.info, Node: Purgem, Next: PushSection, Prev: Psize, Up: Pseudo Ops + +7.89 `.purgem NAME' +=================== + +Undefine the macro NAME, so that later uses of the string will not be +expanded. *Note Macro::. + + +File: as.info, Node: PushSection, Next: Quad, Prev: Purgem, Up: Pseudo Ops + +7.90 `.pushsection NAME [, SUBSECTION] [, "FLAGS"[, @TYPE[,ARGUMENTS]]]' +======================================================================== + +This is one of the ELF section stack manipulation directives. The +others are `.section' (*note Section::), `.subsection' (*note +SubSection::), `.popsection' (*note PopSection::), and `.previous' +(*note Previous::). + + This directive pushes the current section (and subsection) onto the +top of the section stack, and then replaces the current section and +subsection with `name' and `subsection'. The optional `flags', `type' +and `arguments' are treated the same as in the `.section' (*note +Section::) directive. + + +File: as.info, Node: Quad, Next: Reloc, Prev: PushSection, Up: Pseudo Ops + +7.91 `.quad BIGNUMS' +==================== + +`.quad' expects zero or more bignums, separated by commas. For each +bignum, it emits an 8-byte integer. If the bignum won't fit in 8 +bytes, it prints a warning message; and just takes the lowest order 8 +bytes of the bignum. + + The term "quad" comes from contexts in which a "word" is two bytes; +hence _quad_-word for 8 bytes. + + +File: as.info, Node: Reloc, Next: Rept, Prev: Quad, Up: Pseudo Ops + +7.92 `.reloc OFFSET, RELOC_NAME[, EXPRESSION]' +============================================== + +Generate a relocation at OFFSET of type RELOC_NAME with value +EXPRESSION. If OFFSET is a number, the relocation is generated in the +current section. If OFFSET is an expression that resolves to a symbol +plus offset, the relocation is generated in the given symbol's section. +EXPRESSION, if present, must resolve to a symbol plus addend or to an +absolute value, but note that not all targets support an addend. e.g. +ELF REL targets such as i386 store an addend in the section contents +rather than in the relocation. This low level interface does not +support addends stored in the section. + + +File: as.info, Node: Rept, Next: Sbttl, Prev: Reloc, Up: Pseudo Ops + +7.93 `.rept COUNT' +================== + +Repeat the sequence of lines between the `.rept' directive and the next +`.endr' directive COUNT times. + + For example, assembling + + .rept 3 + .long 0 + .endr + + is equivalent to assembling + + .long 0 + .long 0 + .long 0 + + +File: as.info, Node: Sbttl, Next: Scl, Prev: Rept, Up: Pseudo Ops + +7.94 `.sbttl "SUBHEADING"' +========================== + +Use SUBHEADING as the title (third line, immediately after the title +line) when generating assembly listings. + + This directive affects subsequent pages, as well as the current page +if it appears within ten lines of the top of a page. + + +File: as.info, Node: Scl, Next: Section, Prev: Sbttl, Up: Pseudo Ops + +7.95 `.scl CLASS' +================= + +Set the storage-class value for a symbol. This directive may only be +used inside a `.def'/`.endef' pair. Storage class may flag whether a +symbol is static or external, or it may record further symbolic +debugging information. + + +File: as.info, Node: Section, Next: Set, Prev: Scl, Up: Pseudo Ops + +7.96 `.section NAME' +==================== + +Use the `.section' directive to assemble the following code into a +section named NAME. + + This directive is only supported for targets that actually support +arbitrarily named sections; on `a.out' targets, for example, it is not +accepted, even with a standard `a.out' section name. + +COFF Version +------------ + + For COFF targets, the `.section' directive is used in one of the +following ways: + + .section NAME[, "FLAGS"] + .section NAME[, SUBSECTION] + + If the optional argument is quoted, it is taken as flags to use for +the section. Each flag is a single character. The following flags are +recognized: +`b' + bss section (uninitialized data) + +`n' + section is not loaded + +`w' + writable section + +`d' + data section + +`r' + read-only section + +`x' + executable section + +`s' + shared section (meaningful for PE targets) + +`a' + ignored. (For compatibility with the ELF version) + +`y' + section is not readable (meaningful for PE targets) + + If no flags are specified, the default flags depend upon the section +name. If the section name is not recognized, the default will be for +the section to be loaded and writable. Note the `n' and `w' flags +remove attributes from the section, rather than adding them, so if they +are used on their own it will be as if no flags had been specified at +all. + + If the optional argument to the `.section' directive is not quoted, +it is taken as a subsection number (*note Sub-Sections::). + +ELF Version +----------- + + This is one of the ELF section stack manipulation directives. The +others are `.subsection' (*note SubSection::), `.pushsection' (*note +PushSection::), `.popsection' (*note PopSection::), and `.previous' +(*note Previous::). + + For ELF targets, the `.section' directive is used like this: + + .section NAME [, "FLAGS"[, @TYPE[,FLAG_SPECIFIC_ARGUMENTS]]] + + The optional FLAGS argument is a quoted string which may contain any +combination of the following characters: +`a' + section is allocatable + +`w' + section is writable + +`x' + section is executable + +`M' + section is mergeable + +`S' + section contains zero terminated strings + +`G' + section is a member of a section group + +`T' + section is used for thread-local-storage + + The optional TYPE argument may contain one of the following +constants: +`@progbits' + section contains data + +`@nobits' + section does not contain data (i.e., section only occupies space) + +`@note' + section contains data which is used by things other than the + program + +`@init_array' + section contains an array of pointers to init functions + +`@fini_array' + section contains an array of pointers to finish functions + +`@preinit_array' + section contains an array of pointers to pre-init functions + + Many targets only support the first three section types. + + Note on targets where the `@' character is the start of a comment (eg +ARM) then another character is used instead. For example the ARM port +uses the `%' character. + + If FLAGS contains the `M' symbol then the TYPE argument must be +specified as well as an extra argument--ENTSIZE--like this: + + .section NAME , "FLAGS"M, @TYPE, ENTSIZE + + Sections with the `M' flag but not `S' flag must contain fixed size +constants, each ENTSIZE octets long. Sections with both `M' and `S' +must contain zero terminated strings where each character is ENTSIZE +bytes long. The linker may remove duplicates within sections with the +same name, same entity size and same flags. ENTSIZE must be an +absolute expression. For sections with both `M' and `S', a string +which is a suffix of a larger string is considered a duplicate. Thus +`"def"' will be merged with `"abcdef"'; A reference to the first +`"def"' will be changed to a reference to `"abcdef"+3'. + + If FLAGS contains the `G' symbol then the TYPE argument must be +present along with an additional field like this: + + .section NAME , "FLAGS"G, @TYPE, GROUPNAME[, LINKAGE] + + The GROUPNAME field specifies the name of the section group to which +this particular section belongs. The optional linkage field can +contain: +`comdat' + indicates that only one copy of this section should be retained + +`.gnu.linkonce' + an alias for comdat + + Note: if both the M and G flags are present then the fields for the +Merge flag should come first, like this: + + .section NAME , "FLAGS"MG, @TYPE, ENTSIZE, GROUPNAME[, LINKAGE] + + If no flags are specified, the default flags depend upon the section +name. If the section name is not recognized, the default will be for +the section to have none of the above flags: it will not be allocated +in memory, nor writable, nor executable. The section will contain data. + + For ELF targets, the assembler supports another type of `.section' +directive for compatibility with the Solaris assembler: + + .section "NAME"[, FLAGS...] + + Note that the section name is quoted. There may be a sequence of +comma separated flags: +`#alloc' + section is allocatable + +`#write' + section is writable + +`#execinstr' + section is executable + +`#tls' + section is used for thread local storage + + This directive replaces the current section and subsection. See the +contents of the gas testsuite directory `gas/testsuite/gas/elf' for +some examples of how this directive and the other section stack +directives work. + + +File: as.info, Node: Set, Next: Short, Prev: Section, Up: Pseudo Ops + +7.97 `.set SYMBOL, EXPRESSION' +============================== + +Set the value of SYMBOL to EXPRESSION. This changes SYMBOL's value and +type to conform to EXPRESSION. If SYMBOL was flagged as external, it +remains flagged (*note Symbol Attributes::). + + You may `.set' a symbol many times in the same assembly. + + If you `.set' a global symbol, the value stored in the object file +is the last value stored into it. + + The syntax for `set' on the HPPA is `SYMBOL .set EXPRESSION'. + + On Z80 `set' is a real instruction, use `SYMBOL defl EXPRESSION' +instead. + + +File: as.info, Node: Short, Next: Single, Prev: Set, Up: Pseudo Ops + +7.98 `.short EXPRESSIONS' +========================= + +`.short' is normally the same as `.word'. *Note `.word': Word. + + In some configurations, however, `.short' and `.word' generate +numbers of different lengths. *Note Machine Dependencies::. + + +File: as.info, Node: Single, Next: Size, Prev: Short, Up: Pseudo Ops + +7.99 `.single FLONUMS' +====================== + +This directive assembles zero or more flonums, separated by commas. It +has the same effect as `.float'. The exact kind of floating point +numbers emitted depends on how `as' is configured. *Note Machine +Dependencies::. + + +File: as.info, Node: Size, Next: Skip, Prev: Single, Up: Pseudo Ops + +7.100 `.size' +============= + +This directive is used to set the size associated with a symbol. + +COFF Version +------------ + + For COFF targets, the `.size' directive is only permitted inside +`.def'/`.endef' pairs. It is used like this: + + .size EXPRESSION + +ELF Version +----------- + + For ELF targets, the `.size' directive is used like this: + + .size NAME , EXPRESSION + + This directive sets the size associated with a symbol NAME. The +size in bytes is computed from EXPRESSION which can make use of label +arithmetic. This directive is typically used to set the size of +function symbols. + + +File: as.info, Node: Skip, Next: Sleb128, Prev: Size, Up: Pseudo Ops + +7.101 `.skip SIZE , FILL' +========================= + +This directive emits SIZE bytes, each of value FILL. Both SIZE and +FILL are absolute expressions. If the comma and FILL are omitted, FILL +is assumed to be zero. This is the same as `.space'. + + +File: as.info, Node: Sleb128, Next: Space, Prev: Skip, Up: Pseudo Ops + +7.102 `.sleb128 EXPRESSIONS' +============================ + +SLEB128 stands for "signed little endian base 128." This is a compact, +variable length representation of numbers used by the DWARF symbolic +debugging format. *Note `.uleb128': Uleb128. + + +File: as.info, Node: Space, Next: Stab, Prev: Sleb128, Up: Pseudo Ops + +7.103 `.space SIZE , FILL' +========================== + +This directive emits SIZE bytes, each of value FILL. Both SIZE and +FILL are absolute expressions. If the comma and FILL are omitted, FILL +is assumed to be zero. This is the same as `.skip'. + + _Warning:_ `.space' has a completely different meaning for HPPA + targets; use `.block' as a substitute. See `HP9000 Series 800 + Assembly Language Reference Manual' (HP 92432-90001) for the + meaning of the `.space' directive. *Note HPPA Assembler + Directives: HPPA Directives, for a summary. + + +File: as.info, Node: Stab, Next: String, Prev: Space, Up: Pseudo Ops + +7.104 `.stabd, .stabn, .stabs' +============================== + +There are three directives that begin `.stab'. All emit symbols (*note +Symbols::), for use by symbolic debuggers. The symbols are not entered +in the `as' hash table: they cannot be referenced elsewhere in the +source file. Up to five fields are required: + +STRING + This is the symbol's name. It may contain any character except + `\000', so is more general than ordinary symbol names. Some + debuggers used to code arbitrarily complex structures into symbol + names using this field. + +TYPE + An absolute expression. The symbol's type is set to the low 8 + bits of this expression. Any bit pattern is permitted, but `ld' + and debuggers choke on silly bit patterns. + +OTHER + An absolute expression. The symbol's "other" attribute is set to + the low 8 bits of this expression. + +DESC + An absolute expression. The symbol's descriptor is set to the low + 16 bits of this expression. + +VALUE + An absolute expression which becomes the symbol's value. + + If a warning is detected while reading a `.stabd', `.stabn', or +`.stabs' statement, the symbol has probably already been created; you +get a half-formed symbol in your object file. This is compatible with +earlier assemblers! + +`.stabd TYPE , OTHER , DESC' + The "name" of the symbol generated is not even an empty string. + It is a null pointer, for compatibility. Older assemblers used a + null pointer so they didn't waste space in object files with empty + strings. + + The symbol's value is set to the location counter, relocatably. + When your program is linked, the value of this symbol is the + address of the location counter when the `.stabd' was assembled. + +`.stabn TYPE , OTHER , DESC , VALUE' + The name of the symbol is set to the empty string `""'. + +`.stabs STRING , TYPE , OTHER , DESC , VALUE' + All five fields are specified. + + +File: as.info, Node: String, Next: Struct, Prev: Stab, Up: Pseudo Ops + +7.105 `.string' "STR", `.string8' "STR", `.string16' +==================================================== + +"STR", `.string32' "STR", `.string64' "STR" + + Copy the characters in STR to the object file. You may specify more +than one string to copy, separated by commas. Unless otherwise +specified for a particular machine, the assembler marks the end of each +string with a 0 byte. You can use any of the escape sequences +described in *Note Strings: Strings. + + The variants `string16', `string32' and `string64' differ from the +`string' pseudo opcode in that each 8-bit character from STR is copied +and expanded to 16, 32 or 64 bits respectively. The expanded characters +are stored in target endianness byte order. + + Example: + .string32 "BYE" + expands to: + .string "B\0\0\0Y\0\0\0E\0\0\0" /* On little endian targets. */ + .string "\0\0\0B\0\0\0Y\0\0\0E" /* On big endian targets. */ + + +File: as.info, Node: Struct, Next: SubSection, Prev: String, Up: Pseudo Ops + +7.106 `.struct EXPRESSION' +========================== + +Switch to the absolute section, and set the section offset to +EXPRESSION, which must be an absolute expression. You might use this +as follows: + .struct 0 + field1: + .struct field1 + 4 + field2: + .struct field2 + 4 + field3: + This would define the symbol `field1' to have the value 0, the symbol +`field2' to have the value 4, and the symbol `field3' to have the value +8. Assembly would be left in the absolute section, and you would need +to use a `.section' directive of some sort to change to some other +section before further assembly. + + +File: as.info, Node: SubSection, Next: Symver, Prev: Struct, Up: Pseudo Ops + +7.107 `.subsection NAME' +======================== + +This is one of the ELF section stack manipulation directives. The +others are `.section' (*note Section::), `.pushsection' (*note +PushSection::), `.popsection' (*note PopSection::), and `.previous' +(*note Previous::). + + This directive replaces the current subsection with `name'. The +current section is not changed. The replaced subsection is put onto +the section stack in place of the then current top of stack subsection. + + +File: as.info, Node: Symver, Next: Tag, Prev: SubSection, Up: Pseudo Ops + +7.108 `.symver' +=============== + +Use the `.symver' directive to bind symbols to specific version nodes +within a source file. This is only supported on ELF platforms, and is +typically used when assembling files to be linked into a shared library. +There are cases where it may make sense to use this in objects to be +bound into an application itself so as to override a versioned symbol +from a shared library. + + For ELF targets, the `.symver' directive can be used like this: + .symver NAME, NAME2@NODENAME + If the symbol NAME is defined within the file being assembled, the +`.symver' directive effectively creates a symbol alias with the name +NAME2@NODENAME, and in fact the main reason that we just don't try and +create a regular alias is that the @ character isn't permitted in +symbol names. The NAME2 part of the name is the actual name of the +symbol by which it will be externally referenced. The name NAME itself +is merely a name of convenience that is used so that it is possible to +have definitions for multiple versions of a function within a single +source file, and so that the compiler can unambiguously know which +version of a function is being mentioned. The NODENAME portion of the +alias should be the name of a node specified in the version script +supplied to the linker when building a shared library. If you are +attempting to override a versioned symbol from a shared library, then +NODENAME should correspond to the nodename of the symbol you are trying +to override. + + If the symbol NAME is not defined within the file being assembled, +all references to NAME will be changed to NAME2@NODENAME. If no +reference to NAME is made, NAME2@NODENAME will be removed from the +symbol table. + + Another usage of the `.symver' directive is: + .symver NAME, NAME2@@NODENAME + In this case, the symbol NAME must exist and be defined within the +file being assembled. It is similar to NAME2@NODENAME. The difference +is NAME2@@NODENAME will also be used to resolve references to NAME2 by +the linker. + + The third usage of the `.symver' directive is: + .symver NAME, NAME2@@@NODENAME + When NAME is not defined within the file being assembled, it is +treated as NAME2@NODENAME. When NAME is defined within the file being +assembled, the symbol name, NAME, will be changed to NAME2@@NODENAME. + + +File: as.info, Node: Tag, Next: Text, Prev: Symver, Up: Pseudo Ops + +7.109 `.tag STRUCTNAME' +======================= + +This directive is generated by compilers to include auxiliary debugging +information in the symbol table. It is only permitted inside +`.def'/`.endef' pairs. Tags are used to link structure definitions in +the symbol table with instances of those structures. + + +File: as.info, Node: Text, Next: Title, Prev: Tag, Up: Pseudo Ops + +7.110 `.text SUBSECTION' +======================== + +Tells `as' to assemble the following statements onto the end of the +text subsection numbered SUBSECTION, which is an absolute expression. +If SUBSECTION is omitted, subsection number zero is used. + + +File: as.info, Node: Title, Next: Type, Prev: Text, Up: Pseudo Ops + +7.111 `.title "HEADING"' +======================== + +Use HEADING as the title (second line, immediately after the source +file name and pagenumber) when generating assembly listings. + + This directive affects subsequent pages, as well as the current page +if it appears within ten lines of the top of a page. + + +File: as.info, Node: Type, Next: Uleb128, Prev: Title, Up: Pseudo Ops + +7.112 `.type' +============= + +This directive is used to set the type of a symbol. + +COFF Version +------------ + + For COFF targets, this directive is permitted only within +`.def'/`.endef' pairs. It is used like this: + + .type INT + + This records the integer INT as the type attribute of a symbol table +entry. + +ELF Version +----------- + + For ELF targets, the `.type' directive is used like this: + + .type NAME , TYPE DESCRIPTION + + This sets the type of symbol NAME to be either a function symbol or +an object symbol. There are five different syntaxes supported for the +TYPE DESCRIPTION field, in order to provide compatibility with various +other assemblers. + + Because some of the characters used in these syntaxes (such as `@' +and `#') are comment characters for some architectures, some of the +syntaxes below do not work on all architectures. The first variant +will be accepted by the GNU assembler on all architectures so that +variant should be used for maximum portability, if you do not need to +assemble your code with other assemblers. + + The syntaxes supported are: + + .type <name> STT_<TYPE_IN_UPPER_CASE> + .type <name>,#<type> + .type <name>,@<type> + .type <name>,%<type> + .type <name>,"<type>" + + The types supported are: + +`STT_FUNC' +`function' + Mark the symbol as being a function name. + +`STT_GNU_IFUNC' +`gnu_indirect_function' + Mark the symbol as an indirect function when evaluated during reloc + processing. (This is only supported on Linux targeted assemblers). + +`STT_OBJECT' +`object' + Mark the symbol as being a data object. + +`STT_TLS' +`tls_object' + Mark the symbol as being a thead-local data object. + +`STT_COMMON' +`common' + Mark the symbol as being a common data object. + +`STT_NOTYPE' +`notype' + Does not mark the symbol in any way. It is supported just for + completeness. + +`gnu_unique_object' + Marks the symbol as being a globally unique data object. The + dynamic linker will make sure that in the entire process there is + just one symbol with this name and type in use. (This is only + supported on Linux targeted assemblers). + + + Note: Some targets support extra types in addition to those listed +above. + + +File: as.info, Node: Uleb128, Next: Val, Prev: Type, Up: Pseudo Ops + +7.113 `.uleb128 EXPRESSIONS' +============================ + +ULEB128 stands for "unsigned little endian base 128." This is a +compact, variable length representation of numbers used by the DWARF +symbolic debugging format. *Note `.sleb128': Sleb128. + + +File: as.info, Node: Val, Next: Version, Prev: Uleb128, Up: Pseudo Ops + +7.114 `.val ADDR' +================= + +This directive, permitted only within `.def'/`.endef' pairs, records +the address ADDR as the value attribute of a symbol table entry. + + +File: as.info, Node: Version, Next: VTableEntry, Prev: Val, Up: Pseudo Ops + +7.115 `.version "STRING"' +========================= + +This directive creates a `.note' section and places into it an ELF +formatted note of type NT_VERSION. The note's name is set to `string'. + + +File: as.info, Node: VTableEntry, Next: VTableInherit, Prev: Version, Up: Pseudo Ops + +7.116 `.vtable_entry TABLE, OFFSET' +=================================== + +This directive finds or creates a symbol `table' and creates a +`VTABLE_ENTRY' relocation for it with an addend of `offset'. + + +File: as.info, Node: VTableInherit, Next: Warning, Prev: VTableEntry, Up: Pseudo Ops + +7.117 `.vtable_inherit CHILD, PARENT' +===================================== + +This directive finds the symbol `child' and finds or creates the symbol +`parent' and then creates a `VTABLE_INHERIT' relocation for the parent +whose addend is the value of the child symbol. As a special case the +parent name of `0' is treated as referring to the `*ABS*' section. + + +File: as.info, Node: Warning, Next: Weak, Prev: VTableInherit, Up: Pseudo Ops + +7.118 `.warning "STRING"' +========================= + +Similar to the directive `.error' (*note `.error "STRING"': Error.), +but just emits a warning. + + +File: as.info, Node: Weak, Next: Weakref, Prev: Warning, Up: Pseudo Ops + +7.119 `.weak NAMES' +=================== + +This directive sets the weak attribute on the comma separated list of +symbol `names'. If the symbols do not already exist, they will be +created. + + On COFF targets other than PE, weak symbols are a GNU extension. +This directive sets the weak attribute on the comma separated list of +symbol `names'. If the symbols do not already exist, they will be +created. + + On the PE target, weak symbols are supported natively as weak +aliases. When a weak symbol is created that is not an alias, GAS +creates an alternate symbol to hold the default value. + + +File: as.info, Node: Weakref, Next: Word, Prev: Weak, Up: Pseudo Ops + +7.120 `.weakref ALIAS, TARGET' +============================== + +This directive creates an alias to the target symbol that enables the +symbol to be referenced with weak-symbol semantics, but without +actually making it weak. If direct references or definitions of the +symbol are present, then the symbol will not be weak, but if all +references to it are through weak references, the symbol will be marked +as weak in the symbol table. + + The effect is equivalent to moving all references to the alias to a +separate assembly source file, renaming the alias to the symbol in it, +declaring the symbol as weak there, and running a reloadable link to +merge the object files resulting from the assembly of the new source +file and the old source file that had the references to the alias +removed. + + The alias itself never makes to the symbol table, and is entirely +handled within the assembler. + + +File: as.info, Node: Word, Next: Deprecated, Prev: Weakref, Up: Pseudo Ops + +7.121 `.word EXPRESSIONS' +========================= + +This directive expects zero or more EXPRESSIONS, of any section, +separated by commas. + + The size of the number emitted, and its byte order, depend on what +target computer the assembly is for. + + _Warning: Special Treatment to support Compilers_ + + Machines with a 32-bit address space, but that do less than 32-bit +addressing, require the following special treatment. If the machine of +interest to you does 32-bit addressing (or doesn't require it; *note +Machine Dependencies::), you can ignore this issue. + + In order to assemble compiler output into something that works, `as' +occasionally does strange things to `.word' directives. Directives of +the form `.word sym1-sym2' are often emitted by compilers as part of +jump tables. Therefore, when `as' assembles a directive of the form +`.word sym1-sym2', and the difference between `sym1' and `sym2' does +not fit in 16 bits, `as' creates a "secondary jump table", immediately +before the next label. This secondary jump table is preceded by a +short-jump to the first byte after the secondary table. This +short-jump prevents the flow of control from accidentally falling into +the new table. Inside the table is a long-jump to `sym2'. The +original `.word' contains `sym1' minus the address of the long-jump to +`sym2'. + + If there were several occurrences of `.word sym1-sym2' before the +secondary jump table, all of them are adjusted. If there was a `.word +sym3-sym4', that also did not fit in sixteen bits, a long-jump to +`sym4' is included in the secondary jump table, and the `.word' +directives are adjusted to contain `sym3' minus the address of the +long-jump to `sym4'; and so on, for as many entries in the original +jump table as necessary. + + +File: as.info, Node: Deprecated, Prev: Word, Up: Pseudo Ops + +7.122 Deprecated Directives +=========================== + +One day these directives won't work. They are included for +compatibility with older assemblers. +.abort + +.line + + +File: as.info, Node: Object Attributes, Next: Machine Dependencies, Prev: Pseudo Ops, Up: Top + +8 Object Attributes +******************* + +`as' assembles source files written for a specific architecture into +object files for that architecture. But not all object files are alike. +Many architectures support incompatible variations. For instance, +floating point arguments might be passed in floating point registers if +the object file requires hardware floating point support--or floating +point arguments might be passed in integer registers if the object file +supports processors with no hardware floating point unit. Or, if two +objects are built for different generations of the same architecture, +the combination may require the newer generation at run-time. + + This information is useful during and after linking. At link time, +`ld' can warn about incompatible object files. After link time, tools +like `gdb' can use it to process the linked file correctly. + + Compatibility information is recorded as a series of object +attributes. Each attribute has a "vendor", "tag", and "value". The +vendor is a string, and indicates who sets the meaning of the tag. The +tag is an integer, and indicates what property the attribute describes. +The value may be a string or an integer, and indicates how the +property affects this object. Missing attributes are the same as +attributes with a zero value or empty string value. + + Object attributes were developed as part of the ABI for the ARM +Architecture. The file format is documented in `ELF for the ARM +Architecture'. + +* Menu: + +* GNU Object Attributes:: GNU Object Attributes +* Defining New Object Attributes:: Defining New Object Attributes + + +File: as.info, Node: GNU Object Attributes, Next: Defining New Object Attributes, Up: Object Attributes + +8.1 GNU Object Attributes +========================= + +The `.gnu_attribute' directive records an object attribute with vendor +`gnu'. + + Except for `Tag_compatibility', which has both an integer and a +string for its value, GNU attributes have a string value if the tag +number is odd and an integer value if the tag number is even. The +second bit (`TAG & 2' is set for architecture-independent attributes +and clear for architecture-dependent ones. + +8.1.1 Common GNU attributes +--------------------------- + +These attributes are valid on all architectures. + +Tag_compatibility (32) + The compatibility attribute takes an integer flag value and a + vendor name. If the flag value is 0, the file is compatible with + other toolchains. If it is 1, then the file is only compatible + with the named toolchain. If it is greater than 1, the file can + only be processed by other toolchains under some private + arrangement indicated by the flag value and the vendor name. + +8.1.2 MIPS Attributes +--------------------- + +Tag_GNU_MIPS_ABI_FP (4) + The floating-point ABI used by this object file. The value will + be: + + * 0 for files not affected by the floating-point ABI. + + * 1 for files using the hardware floating-point with a standard + double-precision FPU. + + * 2 for files using the hardware floating-point ABI with a + single-precision FPU. + + * 3 for files using the software floating-point ABI. + + * 4 for files using the hardware floating-point ABI with 64-bit + wide double-precision floating-point registers and 32-bit + wide general purpose registers. + +8.1.3 PowerPC Attributes +------------------------ + +Tag_GNU_Power_ABI_FP (4) + The floating-point ABI used by this object file. The value will + be: + + * 0 for files not affected by the floating-point ABI. + + * 1 for files using double-precision hardware floating-point + ABI. + + * 2 for files using the software floating-point ABI. + + * 3 for files using single-precision hardware floating-point + ABI. + +Tag_GNU_Power_ABI_Vector (8) + The vector ABI used by this object file. The value will be: + + * 0 for files not affected by the vector ABI. + + * 1 for files using general purpose registers to pass vectors. + + * 2 for files using AltiVec registers to pass vectors. + + * 3 for files using SPE registers to pass vectors. + + +File: as.info, Node: Defining New Object Attributes, Prev: GNU Object Attributes, Up: Object Attributes + +8.2 Defining New Object Attributes +================================== + +If you want to define a new GNU object attribute, here are the places +you will need to modify. New attributes should be discussed on the +`binutils' mailing list. + + * This manual, which is the official register of attributes. + + * The header for your architecture `include/elf', to define the tag. + + * The `bfd' support file for your architecture, to merge the + attribute and issue any appropriate link warnings. + + * Test cases in `ld/testsuite' for merging and link warnings. + + * `binutils/readelf.c' to display your attribute. + + * GCC, if you want the compiler to mark the attribute automatically. + + +File: as.info, Node: Machine Dependencies, Next: Reporting Bugs, Prev: Object Attributes, Up: Top + +9 Machine Dependent Features +**************************** + +The machine instruction sets are (almost by definition) different on +each machine where `as' runs. Floating point representations vary as +well, and `as' often supports a few additional directives or +command-line options for compatibility with other assemblers on a +particular platform. Finally, some versions of `as' support special +pseudo-instructions for branch optimization. + + This chapter discusses most of these differences, though it does not +include details on any machine's instruction set. For details on that +subject, see the hardware manufacturer's manual. + +* Menu: + + +* Alpha-Dependent:: Alpha Dependent Features + +* ARC-Dependent:: ARC Dependent Features + +* ARM-Dependent:: ARM Dependent Features + +* AVR-Dependent:: AVR Dependent Features + +* Blackfin-Dependent:: Blackfin Dependent Features + +* CR16-Dependent:: CR16 Dependent Features + +* CRIS-Dependent:: CRIS Dependent Features + +* D10V-Dependent:: D10V Dependent Features + +* D30V-Dependent:: D30V Dependent Features + +* H8/300-Dependent:: Renesas H8/300 Dependent Features + +* HPPA-Dependent:: HPPA Dependent Features + +* ESA/390-Dependent:: IBM ESA/390 Dependent Features + +* i386-Dependent:: Intel 80386 and AMD x86-64 Dependent Features + +* i860-Dependent:: Intel 80860 Dependent Features + +* i960-Dependent:: Intel 80960 Dependent Features + +* IA-64-Dependent:: Intel IA-64 Dependent Features + +* IP2K-Dependent:: IP2K Dependent Features + +* LM32-Dependent:: LM32 Dependent Features + +* M32C-Dependent:: M32C Dependent Features + +* M32R-Dependent:: M32R Dependent Features + +* M68K-Dependent:: M680x0 Dependent Features + +* M68HC11-Dependent:: M68HC11 and 68HC12 Dependent Features + +* MicroBlaze-Dependent:: MICROBLAZE Dependent Features + +* MIPS-Dependent:: MIPS Dependent Features + +* MMIX-Dependent:: MMIX Dependent Features + +* MSP430-Dependent:: MSP430 Dependent Features + +* SH-Dependent:: Renesas / SuperH SH Dependent Features +* SH64-Dependent:: SuperH SH64 Dependent Features + +* PDP-11-Dependent:: PDP-11 Dependent Features + +* PJ-Dependent:: picoJava Dependent Features + +* PPC-Dependent:: PowerPC Dependent Features + +* S/390-Dependent:: IBM S/390 Dependent Features + +* SCORE-Dependent:: SCORE Dependent Features + +* Sparc-Dependent:: SPARC Dependent Features + +* TIC54X-Dependent:: TI TMS320C54x Dependent Features + +* V850-Dependent:: V850 Dependent Features + +* Xtensa-Dependent:: Xtensa Dependent Features + +* Z80-Dependent:: Z80 Dependent Features + +* Z8000-Dependent:: Z8000 Dependent Features + +* Vax-Dependent:: VAX Dependent Features + + +File: as.info, Node: Alpha-Dependent, Next: ARC-Dependent, Up: Machine Dependencies + +9.1 Alpha Dependent Features +============================ + +* Menu: + +* Alpha Notes:: Notes +* Alpha Options:: Options +* Alpha Syntax:: Syntax +* Alpha Floating Point:: Floating Point +* Alpha Directives:: Alpha Machine Directives +* Alpha Opcodes:: Opcodes + + +File: as.info, Node: Alpha Notes, Next: Alpha Options, Up: Alpha-Dependent + +9.1.1 Notes +----------- + +The documentation here is primarily for the ELF object format. `as' +also supports the ECOFF and EVAX formats, but features specific to +these formats are not yet documented. + + +File: as.info, Node: Alpha Options, Next: Alpha Syntax, Prev: Alpha Notes, Up: Alpha-Dependent + +9.1.2 Options +------------- + +`-mCPU' + This option specifies the target processor. If an attempt is made + to assemble an instruction which will not execute on the target + processor, the assembler may either expand the instruction as a + macro or issue an error message. This option is equivalent to the + `.arch' directive. + + The following processor names are recognized: `21064', `21064a', + `21066', `21068', `21164', `21164a', `21164pc', `21264', `21264a', + `21264b', `ev4', `ev5', `lca45', `ev5', `ev56', `pca56', `ev6', + `ev67', `ev68'. The special name `all' may be used to allow the + assembler to accept instructions valid for any Alpha processor. + + In order to support existing practice in OSF/1 with respect to + `.arch', and existing practice within `MILO' (the Linux ARC + bootloader), the numbered processor names (e.g. 21064) enable the + processor-specific PALcode instructions, while the + "electro-vlasic" names (e.g. `ev4') do not. + +`-mdebug' +`-no-mdebug' + Enables or disables the generation of `.mdebug' encapsulation for + stabs directives and procedure descriptors. The default is to + automatically enable `.mdebug' when the first stabs directive is + seen. + +`-relax' + This option forces all relocations to be put into the object file, + instead of saving space and resolving some relocations at assembly + time. Note that this option does not propagate all symbol + arithmetic into the object file, because not all symbol arithmetic + can be represented. However, the option can still be useful in + specific applications. + +`-replace' + +`-noreplace' + Enables or disables the optimization of procedure calls, both at + assemblage and at link time. These options are only available for + VMS targets and `-replace' is the default. See section 1.4.1 of + the OpenVMS Linker Utility Manual. + +`-g' + This option is used when the compiler generates debug information. + When `gcc' is using `mips-tfile' to generate debug information + for ECOFF, local labels must be passed through to the object file. + Otherwise this option has no effect. + +`-GSIZE' + A local common symbol larger than SIZE is placed in `.bss', while + smaller symbols are placed in `.sbss'. + +`-F' +`-32addr' + These options are ignored for backward compatibility. + + +File: as.info, Node: Alpha Syntax, Next: Alpha Floating Point, Prev: Alpha Options, Up: Alpha-Dependent + +9.1.3 Syntax +------------ + +The assembler syntax closely follow the Alpha Reference Manual; +assembler directives and general syntax closely follow the OSF/1 and +OpenVMS syntax, with a few differences for ELF. + +* Menu: + +* Alpha-Chars:: Special Characters +* Alpha-Regs:: Register Names +* Alpha-Relocs:: Relocations + + +File: as.info, Node: Alpha-Chars, Next: Alpha-Regs, Up: Alpha Syntax + +9.1.3.1 Special Characters +.......................... + +`#' is the line comment character. + + `;' can be used instead of a newline to separate statements. + + +File: as.info, Node: Alpha-Regs, Next: Alpha-Relocs, Prev: Alpha-Chars, Up: Alpha Syntax + +9.1.3.2 Register Names +...................... + +The 32 integer registers are referred to as `$N' or `$rN'. In +addition, registers 15, 28, 29, and 30 may be referred to by the +symbols `$fp', `$at', `$gp', and `$sp' respectively. + + The 32 floating-point registers are referred to as `$fN'. + + +File: as.info, Node: Alpha-Relocs, Prev: Alpha-Regs, Up: Alpha Syntax + +9.1.3.3 Relocations +................... + +Some of these relocations are available for ECOFF, but mostly only for +ELF. They are modeled after the relocation format introduced in +Digital Unix 4.0, but there are additions. + + The format is `!TAG' or `!TAG!NUMBER' where TAG is the name of the +relocation. In some cases NUMBER is used to relate specific +instructions. + + The relocation is placed at the end of the instruction like so: + + ldah $0,a($29) !gprelhigh + lda $0,a($0) !gprellow + ldq $1,b($29) !literal!100 + ldl $2,0($1) !lituse_base!100 + +`!literal' +`!literal!N' + Used with an `ldq' instruction to load the address of a symbol + from the GOT. + + A sequence number N is optional, and if present is used to pair + `lituse' relocations with this `literal' relocation. The `lituse' + relocations are used by the linker to optimize the code based on + the final location of the symbol. + + Note that these optimizations are dependent on the data flow of the + program. Therefore, if _any_ `lituse' is paired with a `literal' + relocation, then _all_ uses of the register set by the `literal' + instruction must also be marked with `lituse' relocations. This + is because the original `literal' instruction may be deleted or + transformed into another instruction. + + Also note that there may be a one-to-many relationship between + `literal' and `lituse', but not a many-to-one. That is, if there + are two code paths that load up the same address and feed the + value to a single use, then the use may not use a `lituse' + relocation. + +`!lituse_base!N' + Used with any memory format instruction (e.g. `ldl') to indicate + that the literal is used for an address load. The offset field of + the instruction must be zero. During relaxation, the code may be + altered to use a gp-relative load. + +`!lituse_jsr!N' + Used with a register branch format instruction (e.g. `jsr') to + indicate that the literal is used for a call. During relaxation, + the code may be altered to use a direct branch (e.g. `bsr'). + +`!lituse_jsrdirect!N' + Similar to `lituse_jsr', but also that this call cannot be vectored + through a PLT entry. This is useful for functions with special + calling conventions which do not allow the normal call-clobbered + registers to be clobbered. + +`!lituse_bytoff!N' + Used with a byte mask instruction (e.g. `extbl') to indicate that + only the low 3 bits of the address are relevant. During + relaxation, the code may be altered to use an immediate instead of + a register shift. + +`!lituse_addr!N' + Used with any other instruction to indicate that the original + address is in fact used, and the original `ldq' instruction may + not be altered or deleted. This is useful in conjunction with + `lituse_jsr' to test whether a weak symbol is defined. + + ldq $27,foo($29) !literal!1 + beq $27,is_undef !lituse_addr!1 + jsr $26,($27),foo !lituse_jsr!1 + +`!lituse_tlsgd!N' + Used with a register branch format instruction to indicate that the + literal is the call to `__tls_get_addr' used to compute the + address of the thread-local storage variable whose descriptor was + loaded with `!tlsgd!N'. + +`!lituse_tlsldm!N' + Used with a register branch format instruction to indicate that the + literal is the call to `__tls_get_addr' used to compute the + address of the base of the thread-local storage block for the + current module. The descriptor for the module must have been + loaded with `!tlsldm!N'. + +`!gpdisp!N' + Used with `ldah' and `lda' to load the GP from the current + address, a-la the `ldgp' macro. The source register for the + `ldah' instruction must contain the address of the `ldah' + instruction. There must be exactly one `lda' instruction paired + with the `ldah' instruction, though it may appear anywhere in the + instruction stream. The immediate operands must be zero. + + bsr $26,foo + ldah $29,0($26) !gpdisp!1 + lda $29,0($29) !gpdisp!1 + +`!gprelhigh' + Used with an `ldah' instruction to add the high 16 bits of a + 32-bit displacement from the GP. + +`!gprellow' + Used with any memory format instruction to add the low 16 bits of a + 32-bit displacement from the GP. + +`!gprel' + Used with any memory format instruction to add a 16-bit + displacement from the GP. + +`!samegp' + Used with any branch format instruction to skip the GP load at the + target address. The referenced symbol must have the same GP as the + source object file, and it must be declared to either not use `$27' + or perform a standard GP load in the first two instructions via the + `.prologue' directive. + +`!tlsgd' +`!tlsgd!N' + Used with an `lda' instruction to load the address of a TLS + descriptor for a symbol in the GOT. + + The sequence number N is optional, and if present it used to pair + the descriptor load with both the `literal' loading the address of + the `__tls_get_addr' function and the `lituse_tlsgd' marking the + call to that function. + + For proper relaxation, both the `tlsgd', `literal' and `lituse' + relocations must be in the same extended basic block. That is, + the relocation with the lowest address must be executed first at + runtime. + +`!tlsldm' +`!tlsldm!N' + Used with an `lda' instruction to load the address of a TLS + descriptor for the current module in the GOT. + + Similar in other respects to `tlsgd'. + +`!gotdtprel' + Used with an `ldq' instruction to load the offset of the TLS + symbol within its module's thread-local storage block. Also known + as the dynamic thread pointer offset or dtp-relative offset. + +`!dtprelhi' +`!dtprello' +`!dtprel' + Like `gprel' relocations except they compute dtp-relative offsets. + +`!gottprel' + Used with an `ldq' instruction to load the offset of the TLS + symbol from the thread pointer. Also known as the tp-relative + offset. + +`!tprelhi' +`!tprello' +`!tprel' + Like `gprel' relocations except they compute tp-relative offsets. + + +File: as.info, Node: Alpha Floating Point, Next: Alpha Directives, Prev: Alpha Syntax, Up: Alpha-Dependent + +9.1.4 Floating Point +-------------------- + +The Alpha family uses both IEEE and VAX floating-point numbers. + + +File: as.info, Node: Alpha Directives, Next: Alpha Opcodes, Prev: Alpha Floating Point, Up: Alpha-Dependent + +9.1.5 Alpha Assembler Directives +-------------------------------- + +`as' for the Alpha supports many additional directives for +compatibility with the native assembler. This section describes them +only briefly. + + These are the additional directives in `as' for the Alpha: + +`.arch CPU' + Specifies the target processor. This is equivalent to the `-mCPU' + command-line option. *Note Options: Alpha Options, for a list of + values for CPU. + +`.ent FUNCTION[, N]' + Mark the beginning of FUNCTION. An optional number may follow for + compatibility with the OSF/1 assembler, but is ignored. When + generating `.mdebug' information, this will create a procedure + descriptor for the function. In ELF, it will mark the symbol as a + function a-la the generic `.type' directive. + +`.end FUNCTION' + Mark the end of FUNCTION. In ELF, it will set the size of the + symbol a-la the generic `.size' directive. + +`.mask MASK, OFFSET' + Indicate which of the integer registers are saved in the current + function's stack frame. MASK is interpreted a bit mask in which + bit N set indicates that register N is saved. The registers are + saved in a block located OFFSET bytes from the "canonical frame + address" (CFA) which is the value of the stack pointer on entry to + the function. The registers are saved sequentially, except that + the return address register (normally `$26') is saved first. + + This and the other directives that describe the stack frame are + currently only used when generating `.mdebug' information. They + may in the future be used to generate DWARF2 `.debug_frame' unwind + information for hand written assembly. + +`.fmask MASK, OFFSET' + Indicate which of the floating-point registers are saved in the + current stack frame. The MASK and OFFSET parameters are + interpreted as with `.mask'. + +`.frame FRAMEREG, FRAMEOFFSET, RETREG[, ARGOFFSET]' + Describes the shape of the stack frame. The frame pointer in use + is FRAMEREG; normally this is either `$fp' or `$sp'. The frame + pointer is FRAMEOFFSET bytes below the CFA. The return address is + initially located in RETREG until it is saved as indicated in + `.mask'. For compatibility with OSF/1 an optional ARGOFFSET + parameter is accepted and ignored. It is believed to indicate the + offset from the CFA to the saved argument registers. + +`.prologue N' + Indicate that the stack frame is set up and all registers have been + spilled. The argument N indicates whether and how the function + uses the incoming "procedure vector" (the address of the called + function) in `$27'. 0 indicates that `$27' is not used; 1 + indicates that the first two instructions of the function use `$27' + to perform a load of the GP register; 2 indicates that `$27' is + used in some non-standard way and so the linker cannot elide the + load of the procedure vector during relaxation. + +`.usepv FUNCTION, WHICH' + Used to indicate the use of the `$27' register, similar to + `.prologue', but without the other semantics of needing to be + inside an open `.ent'/`.end' block. + + The WHICH argument should be either `no', indicating that `$27' is + not used, or `std', indicating that the first two instructions of + the function perform a GP load. + + One might use this directive instead of `.prologue' if you are + also using dwarf2 CFI directives. + +`.gprel32 EXPRESSION' + Computes the difference between the address in EXPRESSION and the + GP for the current object file, and stores it in 4 bytes. In + addition to being smaller than a full 8 byte address, this also + does not require a dynamic relocation when used in a shared + library. + +`.t_floating EXPRESSION' + Stores EXPRESSION as an IEEE double precision value. + +`.s_floating EXPRESSION' + Stores EXPRESSION as an IEEE single precision value. + +`.f_floating EXPRESSION' + Stores EXPRESSION as a VAX F format value. + +`.g_floating EXPRESSION' + Stores EXPRESSION as a VAX G format value. + +`.d_floating EXPRESSION' + Stores EXPRESSION as a VAX D format value. + +`.set FEATURE' + Enables or disables various assembler features. Using the positive + name of the feature enables while using `noFEATURE' disables. + + `at' + Indicates that macro expansions may clobber the "assembler + temporary" (`$at' or `$28') register. Some macros may not be + expanded without this and will generate an error message if + `noat' is in effect. When `at' is in effect, a warning will + be generated if `$at' is used by the programmer. + + `macro' + Enables the expansion of macro instructions. Note that + variants of real instructions, such as `br label' vs `br + $31,label' are considered alternate forms and not macros. + + `move' + `reorder' + `volatile' + These control whether and how the assembler may re-order + instructions. Accepted for compatibility with the OSF/1 + assembler, but `as' does not do instruction scheduling, so + these features are ignored. + + The following directives are recognized for compatibility with the +OSF/1 assembler but are ignored. + + .proc .aproc + .reguse .livereg + .option .aent + .ugen .eflag + .alias .noalias + + +File: as.info, Node: Alpha Opcodes, Prev: Alpha Directives, Up: Alpha-Dependent + +9.1.6 Opcodes +------------- + +For detailed information on the Alpha machine instruction set, see the +Alpha Architecture Handbook +(ftp://ftp.digital.com/pub/Digital/info/semiconductor/literature/alphaahb.pdf). + + +File: as.info, Node: ARC-Dependent, Next: ARM-Dependent, Prev: Alpha-Dependent, Up: Machine Dependencies + +9.2 ARC Dependent Features +========================== + +* Menu: + +* ARC Options:: Options +* ARC Syntax:: Syntax +* ARC Floating Point:: Floating Point +* ARC Directives:: ARC Machine Directives +* ARC Opcodes:: Opcodes + + +File: as.info, Node: ARC Options, Next: ARC Syntax, Up: ARC-Dependent + +9.2.1 Options +------------- + +`-marc[5|6|7|8]' + This option selects the core processor variant. Using `-marc' is + the same as `-marc6', which is also the default. + + `arc5' + Base instruction set. + + `arc6' + Jump-and-link (jl) instruction. No requirement of an + instruction between setting flags and conditional jump. For + example: + + mov.f r0,r1 + beq foo + + `arc7' + Break (brk) and sleep (sleep) instructions. + + `arc8' + Software interrupt (swi) instruction. + + + Note: the `.option' directive can to be used to select a core + variant from within assembly code. + +`-EB' + This option specifies that the output generated by the assembler + should be marked as being encoded for a big-endian processor. + +`-EL' + This option specifies that the output generated by the assembler + should be marked as being encoded for a little-endian processor - + this is the default. + + + +File: as.info, Node: ARC Syntax, Next: ARC Floating Point, Prev: ARC Options, Up: ARC-Dependent + +9.2.2 Syntax +------------ + +* Menu: + +* ARC-Chars:: Special Characters +* ARC-Regs:: Register Names + + +File: as.info, Node: ARC-Chars, Next: ARC-Regs, Up: ARC Syntax + +9.2.2.1 Special Characters +.......................... + +*TODO* + + +File: as.info, Node: ARC-Regs, Prev: ARC-Chars, Up: ARC Syntax + +9.2.2.2 Register Names +...................... + +*TODO* + + +File: as.info, Node: ARC Floating Point, Next: ARC Directives, Prev: ARC Syntax, Up: ARC-Dependent + +9.2.3 Floating Point +-------------------- + +The ARC core does not currently have hardware floating point support. +Software floating point support is provided by `GCC' and uses IEEE +floating-point numbers. + + +File: as.info, Node: ARC Directives, Next: ARC Opcodes, Prev: ARC Floating Point, Up: ARC-Dependent + +9.2.4 ARC Machine Directives +---------------------------- + +The ARC version of `as' supports the following additional machine +directives: + +`.2byte EXPRESSIONS' + *TODO* + +`.3byte EXPRESSIONS' + *TODO* + +`.4byte EXPRESSIONS' + *TODO* + +`.extAuxRegister NAME,ADDRESS,MODE' + The ARCtangent A4 has extensible auxiliary register space. The + auxiliary registers can be defined in the assembler source code by + using this directive. The first parameter is the NAME of the new + auxiallry register. The second parameter is the ADDRESS of the + register in the auxiliary register memory map for the variant of + the ARC. The third parameter specifies the MODE in which the + register can be operated is and it can be one of: + + `r (readonly)' + + `w (write only)' + + `r|w (read or write)' + + For example: + + .extAuxRegister mulhi,0x12,w + + This specifies an extension auxiliary register called _mulhi_ + which is at address 0x12 in the memory space and which is only + writable. + +`.extCondCode SUFFIX,VALUE' + The condition codes on the ARCtangent A4 are extensible and can be + specified by means of this assembler directive. They are specified + by the suffix and the value for the condition code. They can be + used to specify extra condition codes with any values. For + example: + + .extCondCode is_busy,0x14 + + add.is_busy r1,r2,r3 + bis_busy _main + +`.extCoreRegister NAME,REGNUM,MODE,SHORTCUT' + Specifies an extension core register NAME for the application. + This allows a register NAME with a valid REGNUM between 0 and 60, + with the following as valid values for MODE + + `_r_ (readonly)' + + `_w_ (write only)' + + `_r|w_ (read or write)' + + The other parameter gives a description of the register having a + SHORTCUT in the pipeline. The valid values are: + + `can_shortcut' + + `cannot_shortcut' + + For example: + + .extCoreRegister mlo,57,r,can_shortcut + + This defines an extension core register mlo with the value 57 which + can shortcut the pipeline. + +`.extInstruction NAME,OPCODE,SUBOPCODE,SUFFIXCLASS,SYNTAXCLASS' + The ARCtangent A4 allows the user to specify extension + instructions. The extension instructions are not macros. The + assembler creates encodings for use of these instructions + according to the specification by the user. The parameters are: + + *NAME + Name of the extension instruction + + *OPCODE + Opcode to be used. (Bits 27:31 in the encoding). Valid values + 0x10-0x1f or 0x03 + + *SUBOPCODE + Subopcode to be used. Valid values are from 0x09-0x3f. + However the correct value also depends on SYNTAXCLASS + + *SUFFIXCLASS + Determines the kinds of suffixes to be allowed. Valid values + are `SUFFIX_NONE', `SUFFIX_COND', `SUFFIX_FLAG' which + indicates the absence or presence of conditional suffixes and + flag setting by the extension instruction. It is also + possible to specify that an instruction sets the flags and is + conditional by using `SUFFIX_CODE' | `SUFFIX_FLAG'. + + *SYNTAXCLASS + Determines the syntax class for the instruction. It can have + the following values: + + ``SYNTAX_2OP':' + 2 Operand Instruction + + ``SYNTAX_3OP':' + 3 Operand Instruction + + In addition there could be modifiers for the syntax class as + described below: + + Syntax Class Modifiers are: + + - `OP1_MUST_BE_IMM': Modifies syntax class SYNTAX_3OP, + specifying that the first operand of a three-operand + instruction must be an immediate (i.e., the result is + discarded). OP1_MUST_BE_IMM is used by bitwise ORing it + with SYNTAX_3OP as given in the example below. This + could usually be used to set the flags using specific + instructions and not retain results. + + - `OP1_IMM_IMPLIED': Modifies syntax class SYNTAX_20P, it + specifies that there is an implied immediate destination + operand which does not appear in the syntax. For + example, if the source code contains an instruction like: + + inst r1,r2 + + it really means that the first argument is an implied + immediate (that is, the result is discarded). This is + the same as though the source code were: inst 0,r1,r2. + You use OP1_IMM_IMPLIED by bitwise ORing it with + SYNTAX_20P. + + + For example, defining 64-bit multiplier with immediate operands: + + .extInstruction mp64,0x14,0x0,SUFFIX_COND | SUFFIX_FLAG , + SYNTAX_3OP|OP1_MUST_BE_IMM + + The above specifies an extension instruction called mp64 which has + 3 operands, sets the flags, can be used with a condition code, for + which the first operand is an immediate. (Equivalent to + discarding the result of the operation). + + .extInstruction mul64,0x14,0x00,SUFFIX_COND, SYNTAX_2OP|OP1_IMM_IMPLIED + + This describes a 2 operand instruction with an implicit first + immediate operand. The result of this operation would be + discarded. + +`.half EXPRESSIONS' + *TODO* + +`.long EXPRESSIONS' + *TODO* + +`.option ARC|ARC5|ARC6|ARC7|ARC8' + The `.option' directive must be followed by the desired core + version. Again `arc' is an alias for `arc6'. + + Note: the `.option' directive overrides the command line option + `-marc'; a warning is emitted when the version is not consistent + between the two - even for the implicit default core version + (arc6). + +`.short EXPRESSIONS' + *TODO* + +`.word EXPRESSIONS' + *TODO* + + + +File: as.info, Node: ARC Opcodes, Prev: ARC Directives, Up: ARC-Dependent + +9.2.5 Opcodes +------------- + +For information on the ARC instruction set, see `ARC Programmers +Reference Manual', ARC International (www.arc.com) + + +File: as.info, Node: ARM-Dependent, Next: AVR-Dependent, Prev: ARC-Dependent, Up: Machine Dependencies + +9.3 ARM Dependent Features +========================== + +* Menu: + +* ARM Options:: Options +* ARM Syntax:: Syntax +* ARM Floating Point:: Floating Point +* ARM Directives:: ARM Machine Directives +* ARM Opcodes:: Opcodes +* ARM Mapping Symbols:: Mapping Symbols +* ARM Unwinding Tutorial:: Unwinding + + +File: as.info, Node: ARM Options, Next: ARM Syntax, Up: ARM-Dependent + +9.3.1 Options +------------- + +`-mcpu=PROCESSOR[+EXTENSION...]' + This option specifies the target processor. The assembler will + issue an error message if an attempt is made to assemble an + instruction which will not execute on the target processor. The + following processor names are recognized: `arm1', `arm2', `arm250', + `arm3', `arm6', `arm60', `arm600', `arm610', `arm620', `arm7', + `arm7m', `arm7d', `arm7dm', `arm7di', `arm7dmi', `arm70', `arm700', + `arm700i', `arm710', `arm710t', `arm720', `arm720t', `arm740t', + `arm710c', `arm7100', `arm7500', `arm7500fe', `arm7t', `arm7tdmi', + `arm7tdmi-s', `arm8', `arm810', `strongarm', `strongarm1', + `strongarm110', `strongarm1100', `strongarm1110', `arm9', `arm920', + `arm920t', `arm922t', `arm940t', `arm9tdmi', `fa526' (Faraday + FA526 processor), `fa626' (Faraday FA626 processor), `arm9e', + `arm926e', `arm926ej-s', `arm946e-r0', `arm946e', `arm946e-s', + `arm966e-r0', `arm966e', `arm966e-s', `arm968e-s', `arm10t', + `arm10tdmi', `arm10e', `arm1020', `arm1020t', `arm1020e', + `arm1022e', `arm1026ej-s', `fa626te' (Faraday FA626TE processor), + `fa726te' (Faraday FA726TE processor), `arm1136j-s', `arm1136jf-s', + `arm1156t2-s', `arm1156t2f-s', `arm1176jz-s', `arm1176jzf-s', + `mpcore', `mpcorenovfp', `cortex-a8', `cortex-a9', `cortex-r4', + `cortex-m3', `cortex-m1', `cortex-m0', `ep9312' (ARM920 with + Cirrus Maverick coprocessor), `i80200' (Intel XScale processor) + `iwmmxt' (Intel(r) XScale processor with Wireless MMX(tm) + technology coprocessor) and `xscale'. The special name `all' may + be used to allow the assembler to accept instructions valid for + any ARM processor. + + In addition to the basic instruction set, the assembler can be + told to accept various extension mnemonics that extend the + processor using the co-processor instruction space. For example, + `-mcpu=arm920+maverick' is equivalent to specifying + `-mcpu=ep9312'. The following extensions are currently supported: + `+maverick' `+iwmmxt' and `+xscale'. + +`-march=ARCHITECTURE[+EXTENSION...]' + This option specifies the target architecture. The assembler will + issue an error message if an attempt is made to assemble an + instruction which will not execute on the target architecture. + The following architecture names are recognized: `armv1', `armv2', + `armv2a', `armv2s', `armv3', `armv3m', `armv4', `armv4xm', + `armv4t', `armv4txm', `armv5', `armv5t', `armv5txm', `armv5te', + `armv5texp', `armv6', `armv6j', `armv6k', `armv6z', `armv6zk', + `armv7', `armv7-a', `armv7-r', `armv7-m', `iwmmxt' and `xscale'. + If both `-mcpu' and `-march' are specified, the assembler will use + the setting for `-mcpu'. + + The architecture option can be extended with the same instruction + set extension options as the `-mcpu' option. + +`-mfpu=FLOATING-POINT-FORMAT' + This option specifies the floating point format to assemble for. + The assembler will issue an error message if an attempt is made to + assemble an instruction which will not execute on the target + floating point unit. The following format options are recognized: + `softfpa', `fpe', `fpe2', `fpe3', `fpa', `fpa10', `fpa11', + `arm7500fe', `softvfp', `softvfp+vfp', `vfp', `vfp10', `vfp10-r0', + `vfp9', `vfpxd', `vfpv2' `vfpv3' `vfpv3-d16' `arm1020t', + `arm1020e', `arm1136jf-s', `maverick' and `neon'. + + In addition to determining which instructions are assembled, this + option also affects the way in which the `.double' assembler + directive behaves when assembling little-endian code. + + The default is dependent on the processor selected. For + Architecture 5 or later, the default is to assembler for VFP + instructions; for earlier architectures the default is to assemble + for FPA instructions. + +`-mthumb' + This option specifies that the assembler should start assembling + Thumb instructions; that is, it should behave as though the file + starts with a `.code 16' directive. + +`-mthumb-interwork' + This option specifies that the output generated by the assembler + should be marked as supporting interworking. + +`-mimplicit-it=never' +`-mimplicit-it=always' +`-mimplicit-it=arm' +`-mimplicit-it=thumb' + The `-mimplicit-it' option controls the behavior of the assembler + when conditional instructions are not enclosed in IT blocks. + There are four possible behaviors. If `never' is specified, such + constructs cause a warning in ARM code and an error in Thumb-2 + code. If `always' is specified, such constructs are accepted in + both ARM and Thumb-2 code, where the IT instruction is added + implicitly. If `arm' is specified, such constructs are accepted + in ARM code and cause an error in Thumb-2 code. If `thumb' is + specified, such constructs cause a warning in ARM code and are + accepted in Thumb-2 code. If you omit this option, the behavior + is equivalent to `-mimplicit-it=arm'. + +`-mapcs `[26|32]'' + This option specifies that the output generated by the assembler + should be marked as supporting the indicated version of the Arm + Procedure. Calling Standard. + +`-matpcs' + This option specifies that the output generated by the assembler + should be marked as supporting the Arm/Thumb Procedure Calling + Standard. If enabled this option will cause the assembler to + create an empty debugging section in the object file called + .arm.atpcs. Debuggers can use this to determine the ABI being + used by. + +`-mapcs-float' + This indicates the floating point variant of the APCS should be + used. In this variant floating point arguments are passed in FP + registers rather than integer registers. + +`-mapcs-reentrant' + This indicates that the reentrant variant of the APCS should be + used. This variant supports position independent code. + +`-mfloat-abi=ABI' + This option specifies that the output generated by the assembler + should be marked as using specified floating point ABI. The + following values are recognized: `soft', `softfp' and `hard'. + +`-meabi=VER' + This option specifies which EABI version the produced object files + should conform to. The following values are recognized: `gnu', `4' + and `5'. + +`-EB' + This option specifies that the output generated by the assembler + should be marked as being encoded for a big-endian processor. + +`-EL' + This option specifies that the output generated by the assembler + should be marked as being encoded for a little-endian processor. + +`-k' + This option specifies that the output of the assembler should be + marked as position-independent code (PIC). + +`--fix-v4bx' + Allow `BX' instructions in ARMv4 code. This is intended for use + with the linker option of the same name. + +`-mwarn-deprecated' +`-mno-warn-deprecated' + Enable or disable warnings about using deprecated options or + features. The default is to warn. + + + +File: as.info, Node: ARM Syntax, Next: ARM Floating Point, Prev: ARM Options, Up: ARM-Dependent + +9.3.2 Syntax +------------ + +* Menu: + +* ARM-Instruction-Set:: Instruction Set +* ARM-Chars:: Special Characters +* ARM-Regs:: Register Names +* ARM-Relocations:: Relocations + + +File: as.info, Node: ARM-Instruction-Set, Next: ARM-Chars, Up: ARM Syntax + +9.3.2.1 Instruction Set Syntax +.............................. + +Two slightly different syntaxes are support for ARM and THUMB +instructions. The default, `divided', uses the old style where ARM and +THUMB instructions had their own, separate syntaxes. The new, +`unified' syntax, which can be selected via the `.syntax' directive, +and has the following main features: + +* + Immediate operands do not require a `#' prefix. + +* + The `IT' instruction may appear, and if it does it is validated + against subsequent conditional affixes. In ARM mode it does not + generate machine code, in THUMB mode it does. + +* + For ARM instructions the conditional affixes always appear at the + end of the instruction. For THUMB instructions conditional + affixes can be used, but only inside the scope of an `IT' + instruction. + +* + All of the instructions new to the V6T2 architecture (and later) + are available. (Only a few such instructions can be written in the + `divided' syntax). + +* + The `.N' and `.W' suffixes are recognized and honored. + +* + All instructions set the flags if and only if they have an `s' + affix. + + +File: as.info, Node: ARM-Chars, Next: ARM-Regs, Prev: ARM-Instruction-Set, Up: ARM Syntax + +9.3.2.2 Special Characters +.......................... + +The presence of a `@' on a line indicates the start of a comment that +extends to the end of the current line. If a `#' appears as the first +character of a line, the whole line is treated as a comment. + + The `;' character can be used instead of a newline to separate +statements. + + Either `#' or `$' can be used to indicate immediate operands. + + *TODO* Explain about /data modifier on symbols. + + +File: as.info, Node: ARM-Regs, Next: ARM-Relocations, Prev: ARM-Chars, Up: ARM Syntax + +9.3.2.3 Register Names +...................... + +*TODO* Explain about ARM register naming, and the predefined names. + + +File: as.info, Node: ARM Floating Point, Next: ARM Directives, Prev: ARM Syntax, Up: ARM-Dependent + +9.3.3 Floating Point +-------------------- + +The ARM family uses IEEE floating-point numbers. + + +File: as.info, Node: ARM-Relocations, Prev: ARM-Regs, Up: ARM Syntax + +9.3.3.1 ARM relocation generation +................................. + +Specific data relocations can be generated by putting the relocation +name in parentheses after the symbol name. For example: + + .word foo(TARGET1) + + This will generate an `R_ARM_TARGET1' relocation against the symbol +FOO. The following relocations are supported: `GOT', `GOTOFF', +`TARGET1', `TARGET2', `SBREL', `TLSGD', `TLSLDM', `TLSLDO', `GOTTPOFF' +and `TPOFF'. + + For compatibility with older toolchains the assembler also accepts +`(PLT)' after branch targets. This will generate the deprecated +`R_ARM_PLT32' relocation. + + Relocations for `MOVW' and `MOVT' instructions can be generated by +prefixing the value with `#:lower16:' and `#:upper16' respectively. +For example to load the 32-bit address of foo into r0: + + MOVW r0, #:lower16:foo + MOVT r0, #:upper16:foo + + +File: as.info, Node: ARM Directives, Next: ARM Opcodes, Prev: ARM Floating Point, Up: ARM-Dependent + +9.3.4 ARM Machine Directives +---------------------------- + +`.2byte EXPRESSION [, EXPRESSION]*' +`.4byte EXPRESSION [, EXPRESSION]*' +`.8byte EXPRESSION [, EXPRESSION]*' + These directives write 2, 4 or 8 byte values to the output section. + +`.align EXPRESSION [, EXPRESSION]' + This is the generic .ALIGN directive. For the ARM however if the + first argument is zero (ie no alignment is needed) the assembler + will behave as if the argument had been 2 (ie pad to the next four + byte boundary). This is for compatibility with ARM's own + assembler. + +`.arch NAME' + Select the target architecture. Valid values for NAME are the + same as for the `-march' commandline option. + +`.arm' + This performs the same action as .CODE 32. + +`.pad #COUNT' + Generate unwinder annotations for a stack adjustment of COUNT + bytes. A positive value indicates the function prologue allocated + stack space by decrementing the stack pointer. + +`.bss' + This directive switches to the `.bss' section. + +`.cantunwind' + Prevents unwinding through the current function. No personality + routine or exception table data is required or permitted. + +`.code `[16|32]'' + This directive selects the instruction set being generated. The + value 16 selects Thumb, with the value 32 selecting ARM. + +`.cpu NAME' + Select the target processor. Valid values for NAME are the same as + for the `-mcpu' commandline option. + +`NAME .dn REGISTER NAME [.TYPE] [[INDEX]]' + +`NAME .qn REGISTER NAME [.TYPE] [[INDEX]]' + The `dn' and `qn' directives are used to create typed and/or + indexed register aliases for use in Advanced SIMD Extension (Neon) + instructions. The former should be used to create aliases of + double-precision registers, and the latter to create aliases of + quad-precision registers. + + If these directives are used to create typed aliases, those + aliases can be used in Neon instructions instead of writing types + after the mnemonic or after each operand. For example: + + x .dn d2.f32 + y .dn d3.f32 + z .dn d4.f32[1] + vmul x,y,z + + This is equivalent to writing the following: + + vmul.f32 d2,d3,d4[1] + + Aliases created using `dn' or `qn' can be destroyed using `unreq'. + +`.eabi_attribute TAG, VALUE' + Set the EABI object attribute TAG to VALUE. + + The TAG is either an attribute number, or one of the following: + `Tag_CPU_raw_name', `Tag_CPU_name', `Tag_CPU_arch', + `Tag_CPU_arch_profile', `Tag_ARM_ISA_use', `Tag_THUMB_ISA_use', + `Tag_VFP_arch', `Tag_WMMX_arch', `Tag_Advanced_SIMD_arch', + `Tag_PCS_config', `Tag_ABI_PCS_R9_use', `Tag_ABI_PCS_RW_data', + `Tag_ABI_PCS_RO_data', `Tag_ABI_PCS_GOT_use', + `Tag_ABI_PCS_wchar_t', `Tag_ABI_FP_rounding', + `Tag_ABI_FP_denormal', `Tag_ABI_FP_exceptions', + `Tag_ABI_FP_user_exceptions', `Tag_ABI_FP_number_model', + `Tag_ABI_align8_needed', `Tag_ABI_align8_preserved', + `Tag_ABI_enum_size', `Tag_ABI_HardFP_use', `Tag_ABI_VFP_args', + `Tag_ABI_WMMX_args', `Tag_ABI_optimization_goals', + `Tag_ABI_FP_optimization_goals', `Tag_compatibility', + `Tag_CPU_unaligned_access', `Tag_VFP_HP_extension', + `Tag_ABI_FP_16bit_format', `Tag_nodefaults', + `Tag_also_compatible_with', `Tag_conformance', `Tag_T2EE_use', + `Tag_Virtualization_use', `Tag_MPextension_use' + + The VALUE is either a `number', `"string"', or `number, "string"' + depending on the tag. + +`.even' + This directive aligns to an even-numbered address. + +`.extend EXPRESSION [, EXPRESSION]*' +`.ldouble EXPRESSION [, EXPRESSION]*' + These directives write 12byte long double floating-point values to + the output section. These are not compatible with current ARM + processors or ABIs. + +`.fnend' + Marks the end of a function with an unwind table entry. The + unwind index table entry is created when this directive is + processed. + + If no personality routine has been specified then standard + personality routine 0 or 1 will be used, depending on the number + of unwind opcodes required. + +`.fnstart' + Marks the start of a function with an unwind table entry. + +`.force_thumb' + This directive forces the selection of Thumb instructions, even if + the target processor does not support those instructions + +`.fpu NAME' + Select the floating-point unit to assemble for. Valid values for + NAME are the same as for the `-mfpu' commandline option. + +`.handlerdata' + Marks the end of the current function, and the start of the + exception table entry for that function. Anything between this + directive and the `.fnend' directive will be added to the + exception table entry. + + Must be preceded by a `.personality' or `.personalityindex' + directive. + +`.inst OPCODE [ , ... ]' + +`.inst.n OPCODE [ , ... ]' + +`.inst.w OPCODE [ , ... ]' + Generates the instruction corresponding to the numerical value + OPCODE. `.inst.n' and `.inst.w' allow the Thumb instruction size + to be specified explicitly, overriding the normal encoding rules. + +`.ldouble EXPRESSION [, EXPRESSION]*' + See `.extend'. + +`.ltorg' + This directive causes the current contents of the literal pool to + be dumped into the current section (which is assumed to be the + .text section) at the current location (aligned to a word + boundary). `GAS' maintains a separate literal pool for each + section and each sub-section. The `.ltorg' directive will only + affect the literal pool of the current section and sub-section. + At the end of assembly all remaining, un-empty literal pools will + automatically be dumped. + + Note - older versions of `GAS' would dump the current literal pool + any time a section change occurred. This is no longer done, since + it prevents accurate control of the placement of literal pools. + +`.movsp REG [, #OFFSET]' + Tell the unwinder that REG contains an offset from the current + stack pointer. If OFFSET is not specified then it is assumed to be + zero. + +`.object_arch NAME' + Override the architecture recorded in the EABI object attribute + section. Valid values for NAME are the same as for the `.arch' + directive. Typically this is useful when code uses runtime + detection of CPU features. + +`.packed EXPRESSION [, EXPRESSION]*' + This directive writes 12-byte packed floating-point values to the + output section. These are not compatible with current ARM + processors or ABIs. + +`.pad #COUNT' + Generate unwinder annotations for a stack adjustment of COUNT + bytes. A positive value indicates the function prologue allocated + stack space by decrementing the stack pointer. + +`.personality NAME' + Sets the personality routine for the current function to NAME. + +`.personalityindex INDEX' + Sets the personality routine for the current function to the EABI + standard routine number INDEX + +`.pool' + This is a synonym for .ltorg. + +`NAME .req REGISTER NAME' + This creates an alias for REGISTER NAME called NAME. For example: + + foo .req r0 + +`.save REGLIST' + Generate unwinder annotations to restore the registers in REGLIST. + The format of REGLIST is the same as the corresponding + store-multiple instruction. + + _core registers_ + .save {r4, r5, r6, lr} + stmfd sp!, {r4, r5, r6, lr} + _FPA registers_ + .save f4, 2 + sfmfd f4, 2, [sp]! + _VFP registers_ + .save {d8, d9, d10} + fstmdx sp!, {d8, d9, d10} + _iWMMXt registers_ + .save {wr10, wr11} + wstrd wr11, [sp, #-8]! + wstrd wr10, [sp, #-8]! + or + .save wr11 + wstrd wr11, [sp, #-8]! + .save wr10 + wstrd wr10, [sp, #-8]! + +`.setfp FPREG, SPREG [, #OFFSET]' + Make all unwinder annotations relative to a frame pointer. + Without this the unwinder will use offsets from the stack pointer. + + The syntax of this directive is the same as the `sub' or `mov' + instruction used to set the frame pointer. SPREG must be either + `sp' or mentioned in a previous `.movsp' directive. + + .movsp ip + mov ip, sp + ... + .setfp fp, ip, #4 + sub fp, ip, #4 + +`.secrel32 EXPRESSION [, EXPRESSION]*' + This directive emits relocations that evaluate to the + section-relative offset of each expression's symbol. This + directive is only supported for PE targets. + +`.syntax [`unified' | `divided']' + This directive sets the Instruction Set Syntax as described in the + *Note ARM-Instruction-Set:: section. + +`.thumb' + This performs the same action as .CODE 16. + +`.thumb_func' + This directive specifies that the following symbol is the name of a + Thumb encoded function. This information is necessary in order to + allow the assembler and linker to generate correct code for + interworking between Arm and Thumb instructions and should be used + even if interworking is not going to be performed. The presence + of this directive also implies `.thumb' + + This directive is not neccessary when generating EABI objects. On + these targets the encoding is implicit when generating Thumb code. + +`.thumb_set' + This performs the equivalent of a `.set' directive in that it + creates a symbol which is an alias for another symbol (possibly + not yet defined). This directive also has the added property in + that it marks the aliased symbol as being a thumb function entry + point, in the same way that the `.thumb_func' directive does. + +`.unreq ALIAS-NAME' + This undefines a register alias which was previously defined using + the `req', `dn' or `qn' directives. For example: + + foo .req r0 + .unreq foo + + An error occurs if the name is undefined. Note - this pseudo op + can be used to delete builtin in register name aliases (eg 'r0'). + This should only be done if it is really necessary. + +`.unwind_raw OFFSET, BYTE1, ...' + Insert one of more arbitary unwind opcode bytes, which are known + to adjust the stack pointer by OFFSET bytes. + + For example `.unwind_raw 4, 0xb1, 0x01' is equivalent to `.save + {r0}' + +`.vsave VFP-REGLIST' + Generate unwinder annotations to restore the VFP registers in + VFP-REGLIST using FLDMD. Also works for VFPv3 registers that are + to be restored using VLDM. The format of VFP-REGLIST is the same + as the corresponding store-multiple instruction. + + _VFP registers_ + .vsave {d8, d9, d10} + fstmdd sp!, {d8, d9, d10} + _VFPv3 registers_ + .vsave {d15, d16, d17} + vstm sp!, {d15, d16, d17} + + Since FLDMX and FSTMX are now deprecated, this directive should be + used in favour of `.save' for saving VFP registers for ARMv6 and + above. + + + +File: as.info, Node: ARM Opcodes, Next: ARM Mapping Symbols, Prev: ARM Directives, Up: ARM-Dependent + +9.3.5 Opcodes +------------- + +`as' implements all the standard ARM opcodes. It also implements +several pseudo opcodes, including several synthetic load instructions. + +`NOP' + nop + + This pseudo op will always evaluate to a legal ARM instruction + that does nothing. Currently it will evaluate to MOV r0, r0. + +`LDR' + ldr <register> , = <expression> + + If expression evaluates to a numeric constant then a MOV or MVN + instruction will be used in place of the LDR instruction, if the + constant can be generated by either of these instructions. + Otherwise the constant will be placed into the nearest literal + pool (if it not already there) and a PC relative LDR instruction + will be generated. + +`ADR' + adr <register> <label> + + This instruction will load the address of LABEL into the indicated + register. The instruction will evaluate to a PC relative ADD or + SUB instruction depending upon where the label is located. If the + label is out of range, or if it is not defined in the same file + (and section) as the ADR instruction, then an error will be + generated. This instruction will not make use of the literal pool. + +`ADRL' + adrl <register> <label> + + This instruction will load the address of LABEL into the indicated + register. The instruction will evaluate to one or two PC relative + ADD or SUB instructions depending upon where the label is located. + If a second instruction is not needed a NOP instruction will be + generated in its place, so that this instruction is always 8 bytes + long. + + If the label is out of range, or if it is not defined in the same + file (and section) as the ADRL instruction, then an error will be + generated. This instruction will not make use of the literal pool. + + + For information on the ARM or Thumb instruction sets, see `ARM +Software Development Toolkit Reference Manual', Advanced RISC Machines +Ltd. + + +File: as.info, Node: ARM Mapping Symbols, Next: ARM Unwinding Tutorial, Prev: ARM Opcodes, Up: ARM-Dependent + +9.3.6 Mapping Symbols +--------------------- + +The ARM ELF specification requires that special symbols be inserted +into object files to mark certain features: + +`$a' + At the start of a region of code containing ARM instructions. + +`$t' + At the start of a region of code containing THUMB instructions. + +`$d' + At the start of a region of data. + + + The assembler will automatically insert these symbols for you - there +is no need to code them yourself. Support for tagging symbols ($b, $f, +$p and $m) which is also mentioned in the current ARM ELF specification +is not implemented. This is because they have been dropped from the +new EABI and so tools cannot rely upon their presence. + + +File: as.info, Node: ARM Unwinding Tutorial, Prev: ARM Mapping Symbols, Up: ARM-Dependent + +9.3.7 Unwinding +--------------- + +The ABI for the ARM Architecture specifies a standard format for +exception unwind information. This information is used when an +exception is thrown to determine where control should be transferred. +In particular, the unwind information is used to determine which +function called the function that threw the exception, and which +function called that one, and so forth. This information is also used +to restore the values of callee-saved registers in the function +catching the exception. + + If you are writing functions in assembly code, and those functions +call other functions that throw exceptions, you must use assembly +pseudo ops to ensure that appropriate exception unwind information is +generated. Otherwise, if one of the functions called by your assembly +code throws an exception, the run-time library will be unable to unwind +the stack through your assembly code and your program will not behave +correctly. + + To illustrate the use of these pseudo ops, we will examine the code +that G++ generates for the following C++ input: + + +void callee (int *); + +int +caller () +{ + int i; + callee (&i); + return i; +} + + This example does not show how to throw or catch an exception from +assembly code. That is a much more complex operation and should always +be done in a high-level language, such as C++, that directly supports +exceptions. + + The code generated by one particular version of G++ when compiling +the example above is: + + +_Z6callerv: + .fnstart +.LFB2: + @ Function supports interworking. + @ args = 0, pretend = 0, frame = 8 + @ frame_needed = 1, uses_anonymous_args = 0 + stmfd sp!, {fp, lr} + .save {fp, lr} +.LCFI0: + .setfp fp, sp, #4 + add fp, sp, #4 +.LCFI1: + .pad #8 + sub sp, sp, #8 +.LCFI2: + sub r3, fp, #8 + mov r0, r3 + bl _Z6calleePi + ldr r3, [fp, #-8] + mov r0, r3 + sub sp, fp, #4 + ldmfd sp!, {fp, lr} + bx lr +.LFE2: + .fnend + + Of course, the sequence of instructions varies based on the options +you pass to GCC and on the version of GCC in use. The exact +instructions are not important since we are focusing on the pseudo ops +that are used to generate unwind information. + + An important assumption made by the unwinder is that the stack frame +does not change during the body of the function. In particular, since +we assume that the assembly code does not itself throw an exception, +the only point where an exception can be thrown is from a call, such as +the `bl' instruction above. At each call site, the same saved +registers (including `lr', which indicates the return address) must be +located in the same locations relative to the frame pointer. + + The `.fnstart' (*note .fnstart pseudo op: arm_fnstart.) pseudo op +appears immediately before the first instruction of the function while +the `.fnend' (*note .fnend pseudo op: arm_fnend.) pseudo op appears +immediately after the last instruction of the function. These pseudo +ops specify the range of the function. + + Only the order of the other pseudos ops (e.g., `.setfp' or `.pad') +matters; their exact locations are irrelevant. In the example above, +the compiler emits the pseudo ops with particular instructions. That +makes it easier to understand the code, but it is not required for +correctness. It would work just as well to emit all of the pseudo ops +other than `.fnend' in the same order, but immediately after `.fnstart'. + + The `.save' (*note .save pseudo op: arm_save.) pseudo op indicates +registers that have been saved to the stack so that they can be +restored before the function returns. The argument to the `.save' +pseudo op is a list of registers to save. If a register is +"callee-saved" (as specified by the ABI) and is modified by the +function you are writing, then your code must save the value before it +is modified and restore the original value before the function returns. +If an exception is thrown, the run-time library restores the values of +these registers from their locations on the stack before returning +control to the exception handler. (Of course, if an exception is not +thrown, the function that contains the `.save' pseudo op restores these +registers in the function epilogue, as is done with the `ldmfd' +instruction above.) + + You do not have to save callee-saved registers at the very beginning +of the function and you do not need to use the `.save' pseudo op +immediately following the point at which the registers are saved. +However, if you modify a callee-saved register, you must save it on the +stack before modifying it and before calling any functions which might +throw an exception. And, you must use the `.save' pseudo op to +indicate that you have done so. + + The `.pad' (*note .pad: arm_pad.) pseudo op indicates a modification +of the stack pointer that does not save any registers. The argument is +the number of bytes (in decimal) that are subtracted from the stack +pointer. (On ARM CPUs, the stack grows downwards, so subtracting from +the stack pointer increases the size of the stack.) + + The `.setfp' (*note .setfp pseudo op: arm_setfp.) pseudo op +indicates the register that contains the frame pointer. The first +argument is the register that is set, which is typically `fp'. The +second argument indicates the register from which the frame pointer +takes its value. The third argument, if present, is the value (in +decimal) added to the register specified by the second argument to +compute the value of the frame pointer. You should not modify the +frame pointer in the body of the function. + + If you do not use a frame pointer, then you should not use the +`.setfp' pseudo op. If you do not use a frame pointer, then you should +avoid modifying the stack pointer outside of the function prologue. +Otherwise, the run-time library will be unable to find saved registers +when it is unwinding the stack. + + The pseudo ops described above are sufficient for writing assembly +code that calls functions which may throw exceptions. If you need to +know more about the object-file format used to represent unwind +information, you may consult the `Exception Handling ABI for the ARM +Architecture' available from `http://infocenter.arm.com'. + + +File: as.info, Node: AVR-Dependent, Next: Blackfin-Dependent, Prev: ARM-Dependent, Up: Machine Dependencies + +9.4 AVR Dependent Features +========================== + +* Menu: + +* AVR Options:: Options +* AVR Syntax:: Syntax +* AVR Opcodes:: Opcodes + + +File: as.info, Node: AVR Options, Next: AVR Syntax, Up: AVR-Dependent + +9.4.1 Options +------------- + +`-mmcu=MCU' + Specify ATMEL AVR instruction set or MCU type. + + Instruction set avr1 is for the minimal AVR core, not supported by + the C compiler, only for assembler programs (MCU types: at90s1200, + attiny11, attiny12, attiny15, attiny28). + + Instruction set avr2 (default) is for the classic AVR core with up + to 8K program memory space (MCU types: at90s2313, at90s2323, + at90s2333, at90s2343, attiny22, attiny26, at90s4414, at90s4433, + at90s4434, at90s8515, at90c8534, at90s8535). + + Instruction set avr25 is for the classic AVR core with up to 8K + program memory space plus the MOVW instruction (MCU types: + attiny13, attiny13a, attiny2313, attiny2313a, attiny24, attiny24a, + attiny4313, attiny44, attiny44a, attiny84, attiny25, attiny45, + attiny85, attiny261, attiny261a, attiny461, attiny861, attiny861a, + attiny87, attiny43u, attiny48, attiny88, at86rf401, ata6289). + + Instruction set avr3 is for the classic AVR core with up to 128K + program memory space (MCU types: at43usb355, at76c711). + + Instruction set avr31 is for the classic AVR core with exactly + 128K program memory space (MCU types: atmega103, at43usb320). + + Instruction set avr35 is for classic AVR core plus MOVW, CALL, and + JMP instructions (MCU types: attiny167, attiny327, at90usb82, + at90usb162, atmega8u2, atmega16u2, atmega32u2). + + Instruction set avr4 is for the enhanced AVR core with up to 8K + program memory space (MCU types: atmega48, atmega48p,atmega8, + atmega88, atmega88p, atmega8515, atmega8535, atmega8hva, + atmega4hvd, atmega8hvd, at90pwm1, at90pwm2, at90pwm2b, at90pwm3, + at90pwm3b, at90pwm81, atmega8m1, atmega8c1). + + Instruction set avr5 is for the enhanced AVR core with up to 128K + program memory space (MCU types: atmega16, atmega161, atmega162, + atmega163, atmega164p, atmega165, atmega165p, atmega168, + atmega168p, atmega169, atmega169p, atmega16c1, atmega32, + atmega323, atmega324p, atmega325, atmega325p, atmega3250, + atmega3250p, atmega328p, atmega329, atmega329p, atmega3290, + atmega3290p, atmega406, atmega64, atmega640, atmega644, + atmega644p, atmega644pa, atmega645, atmega6450, atmega649, + atmega6490, atmega16hva, atmega16hvb, atmega32hvb, at90can32, + at90can64, at90pwm216, at90pwm316, atmega32c1, atmega64c1, + atmega16m1, atmega32m1, atmega64m1, atmega16u4, atmega32u4, + atmega32u6, at90usb646, at90usb647, at94k, at90scr100). + + Instruction set avr51 is for the enhanced AVR core with exactly + 128K program memory space (MCU types: atmega128, atmega1280, + atmega1281, atmega1284p, atmega128rfa1, at90can128, at90usb1286, + at90usb1287, m3000f, m3000s, m3001b). + + Instruction set avr6 is for the enhanced AVR core with a 3-byte PC + (MCU types: atmega2560, atmega2561). + +`-mall-opcodes' + Accept all AVR opcodes, even if not supported by `-mmcu'. + +`-mno-skip-bug' + This option disable warnings for skipping two-word instructions. + +`-mno-wrap' + This option reject `rjmp/rcall' instructions with 8K wrap-around. + + + +File: as.info, Node: AVR Syntax, Next: AVR Opcodes, Prev: AVR Options, Up: AVR-Dependent + +9.4.2 Syntax +------------ + +* Menu: + +* AVR-Chars:: Special Characters +* AVR-Regs:: Register Names +* AVR-Modifiers:: Relocatable Expression Modifiers + + +File: as.info, Node: AVR-Chars, Next: AVR-Regs, Up: AVR Syntax + +9.4.2.1 Special Characters +.......................... + +The presence of a `;' on a line indicates the start of a comment that +extends to the end of the current line. If a `#' appears as the first +character of a line, the whole line is treated as a comment. + + The `$' character can be used instead of a newline to separate +statements. + + +File: as.info, Node: AVR-Regs, Next: AVR-Modifiers, Prev: AVR-Chars, Up: AVR Syntax + +9.4.2.2 Register Names +...................... + +The AVR has 32 x 8-bit general purpose working registers `r0', `r1', +... `r31'. Six of the 32 registers can be used as three 16-bit +indirect address register pointers for Data Space addressing. One of +the these address pointers can also be used as an address pointer for +look up tables in Flash program memory. These added function registers +are the 16-bit `X', `Y' and `Z' - registers. + + X = r26:r27 + Y = r28:r29 + Z = r30:r31 + + +File: as.info, Node: AVR-Modifiers, Prev: AVR-Regs, Up: AVR Syntax + +9.4.2.3 Relocatable Expression Modifiers +........................................ + +The assembler supports several modifiers when using relocatable +addresses in AVR instruction operands. The general syntax is the +following: + + modifier(relocatable-expression) + +`lo8' + This modifier allows you to use bits 0 through 7 of an address + expression as 8 bit relocatable expression. + +`hi8' + This modifier allows you to use bits 7 through 15 of an address + expression as 8 bit relocatable expression. This is useful with, + for example, the AVR `ldi' instruction and `lo8' modifier. + + For example + + ldi r26, lo8(sym+10) + ldi r27, hi8(sym+10) + +`hh8' + This modifier allows you to use bits 16 through 23 of an address + expression as 8 bit relocatable expression. Also, can be useful + for loading 32 bit constants. + +`hlo8' + Synonym of `hh8'. + +`hhi8' + This modifier allows you to use bits 24 through 31 of an + expression as 8 bit expression. This is useful with, for example, + the AVR `ldi' instruction and `lo8', `hi8', `hlo8', `hhi8', + modifier. + + For example + + ldi r26, lo8(285774925) + ldi r27, hi8(285774925) + ldi r28, hlo8(285774925) + ldi r29, hhi8(285774925) + ; r29,r28,r27,r26 = 285774925 + +`pm_lo8' + This modifier allows you to use bits 0 through 7 of an address + expression as 8 bit relocatable expression. This modifier useful + for addressing data or code from Flash/Program memory. The using + of `pm_lo8' similar to `lo8'. + +`pm_hi8' + This modifier allows you to use bits 8 through 15 of an address + expression as 8 bit relocatable expression. This modifier useful + for addressing data or code from Flash/Program memory. + +`pm_hh8' + This modifier allows you to use bits 15 through 23 of an address + expression as 8 bit relocatable expression. This modifier useful + for addressing data or code from Flash/Program memory. + + + +File: as.info, Node: AVR Opcodes, Prev: AVR Syntax, Up: AVR-Dependent + +9.4.3 Opcodes +------------- + +For detailed information on the AVR machine instruction set, see +`www.atmel.com/products/AVR'. + + `as' implements all the standard AVR opcodes. The following table +summarizes the AVR opcodes, and their arguments. + + Legend: + r any register + d `ldi' register (r16-r31) + v `movw' even register (r0, r2, ..., r28, r30) + a `fmul' register (r16-r23) + w `adiw' register (r24,r26,r28,r30) + e pointer registers (X,Y,Z) + b base pointer register and displacement ([YZ]+disp) + z Z pointer register (for [e]lpm Rd,Z[+]) + M immediate value from 0 to 255 + n immediate value from 0 to 255 ( n = ~M ). Relocation impossible + s immediate value from 0 to 7 + P Port address value from 0 to 63. (in, out) + p Port address value from 0 to 31. (cbi, sbi, sbic, sbis) + K immediate value from 0 to 63 (used in `adiw', `sbiw') + i immediate value + l signed pc relative offset from -64 to 63 + L signed pc relative offset from -2048 to 2047 + h absolute code address (call, jmp) + S immediate value from 0 to 7 (S = s << 4) + ? use this opcode entry if no parameters, else use next opcode entry + + 1001010010001000 clc + 1001010011011000 clh + 1001010011111000 cli + 1001010010101000 cln + 1001010011001000 cls + 1001010011101000 clt + 1001010010111000 clv + 1001010010011000 clz + 1001010000001000 sec + 1001010001011000 seh + 1001010001111000 sei + 1001010000101000 sen + 1001010001001000 ses + 1001010001101000 set + 1001010000111000 sev + 1001010000011000 sez + 100101001SSS1000 bclr S + 100101000SSS1000 bset S + 1001010100001001 icall + 1001010000001001 ijmp + 1001010111001000 lpm ? + 1001000ddddd010+ lpm r,z + 1001010111011000 elpm ? + 1001000ddddd011+ elpm r,z + 0000000000000000 nop + 1001010100001000 ret + 1001010100011000 reti + 1001010110001000 sleep + 1001010110011000 break + 1001010110101000 wdr + 1001010111101000 spm + 000111rdddddrrrr adc r,r + 000011rdddddrrrr add r,r + 001000rdddddrrrr and r,r + 000101rdddddrrrr cp r,r + 000001rdddddrrrr cpc r,r + 000100rdddddrrrr cpse r,r + 001001rdddddrrrr eor r,r + 001011rdddddrrrr mov r,r + 100111rdddddrrrr mul r,r + 001010rdddddrrrr or r,r + 000010rdddddrrrr sbc r,r + 000110rdddddrrrr sub r,r + 001001rdddddrrrr clr r + 000011rdddddrrrr lsl r + 000111rdddddrrrr rol r + 001000rdddddrrrr tst r + 0111KKKKddddKKKK andi d,M + 0111KKKKddddKKKK cbr d,n + 1110KKKKddddKKKK ldi d,M + 11101111dddd1111 ser d + 0110KKKKddddKKKK ori d,M + 0110KKKKddddKKKK sbr d,M + 0011KKKKddddKKKK cpi d,M + 0100KKKKddddKKKK sbci d,M + 0101KKKKddddKKKK subi d,M + 1111110rrrrr0sss sbrc r,s + 1111111rrrrr0sss sbrs r,s + 1111100ddddd0sss bld r,s + 1111101ddddd0sss bst r,s + 10110PPdddddPPPP in r,P + 10111PPrrrrrPPPP out P,r + 10010110KKddKKKK adiw w,K + 10010111KKddKKKK sbiw w,K + 10011000pppppsss cbi p,s + 10011010pppppsss sbi p,s + 10011001pppppsss sbic p,s + 10011011pppppsss sbis p,s + 111101lllllll000 brcc l + 111100lllllll000 brcs l + 111100lllllll001 breq l + 111101lllllll100 brge l + 111101lllllll101 brhc l + 111100lllllll101 brhs l + 111101lllllll111 brid l + 111100lllllll111 brie l + 111100lllllll000 brlo l + 111100lllllll100 brlt l + 111100lllllll010 brmi l + 111101lllllll001 brne l + 111101lllllll010 brpl l + 111101lllllll000 brsh l + 111101lllllll110 brtc l + 111100lllllll110 brts l + 111101lllllll011 brvc l + 111100lllllll011 brvs l + 111101lllllllsss brbc s,l + 111100lllllllsss brbs s,l + 1101LLLLLLLLLLLL rcall L + 1100LLLLLLLLLLLL rjmp L + 1001010hhhhh111h call h + 1001010hhhhh110h jmp h + 1001010rrrrr0101 asr r + 1001010rrrrr0000 com r + 1001010rrrrr1010 dec r + 1001010rrrrr0011 inc r + 1001010rrrrr0110 lsr r + 1001010rrrrr0001 neg r + 1001000rrrrr1111 pop r + 1001001rrrrr1111 push r + 1001010rrrrr0111 ror r + 1001010rrrrr0010 swap r + 00000001ddddrrrr movw v,v + 00000010ddddrrrr muls d,d + 000000110ddd0rrr mulsu a,a + 000000110ddd1rrr fmul a,a + 000000111ddd0rrr fmuls a,a + 000000111ddd1rrr fmulsu a,a + 1001001ddddd0000 sts i,r + 1001000ddddd0000 lds r,i + 10o0oo0dddddbooo ldd r,b + 100!000dddddee-+ ld r,e + 10o0oo1rrrrrbooo std b,r + 100!001rrrrree-+ st e,r + 1001010100011001 eicall + 1001010000011001 eijmp + + +File: as.info, Node: Blackfin-Dependent, Next: CR16-Dependent, Prev: AVR-Dependent, Up: Machine Dependencies + +9.5 Blackfin Dependent Features +=============================== + +* Menu: + +* Blackfin Options:: Blackfin Options +* Blackfin Syntax:: Blackfin Syntax +* Blackfin Directives:: Blackfin Directives + + +File: as.info, Node: Blackfin Options, Next: Blackfin Syntax, Up: Blackfin-Dependent + +9.5.1 Options +------------- + +`-mcpu=PROCESSOR[-SIREVISION]' + This option specifies the target processor. The optional + SIREVISION is not used in assembler. It's here such that GCC can + easily pass down its `-mcpu=' option. The assembler will issue an + error message if an attempt is made to assemble an instruction + which will not execute on the target processor. The following + processor names are recognized: `bf512', `bf514', `bf516', `bf518', + `bf522', `bf523', `bf524', `bf525', `bf526', `bf527', `bf531', + `bf532', `bf533', `bf534', `bf535' (not implemented yet), `bf536', + `bf537', `bf538', `bf539', `bf542', `bf542m', `bf544', `bf544m', + `bf547', `bf547m', `bf548', `bf548m', `bf549', `bf549m', and + `bf561'. + + + +File: as.info, Node: Blackfin Syntax, Next: Blackfin Directives, Prev: Blackfin Options, Up: Blackfin-Dependent + +9.5.2 Syntax +------------ + +`Special Characters' + Assembler input is free format and may appear anywhere on the line. + One instruction may extend across multiple lines or more than one + instruction may appear on the same line. White space (space, tab, + comments or newline) may appear anywhere between tokens. A token + must not have embedded spaces. Tokens include numbers, register + names, keywords, user identifiers, and also some multicharacter + special symbols like "+=", "/*" or "||". + +`Instruction Delimiting' + A semicolon must terminate every instruction. Sometimes a complete + instruction will consist of more than one operation. There are two + cases where this occurs. The first is when two general operations + are combined. Normally a comma separates the different parts, as + in + + a0= r3.h * r2.l, a1 = r3.l * r2.h ; + + The second case occurs when a general instruction is combined with + one or two memory references for joint issue. The latter portions + are set off by a "||" token. + + a0 = r3.h * r2.l || r1 = [p3++] || r4 = [i2++]; + +`Register Names' + The assembler treats register names and instruction keywords in a + case insensitive manner. User identifiers are case sensitive. + Thus, R3.l, R3.L, r3.l and r3.L are all equivalent input to the + assembler. + + Register names are reserved and may not be used as program + identifiers. + + Some operations (such as "Move Register") require a register pair. + Register pairs are always data registers and are denoted using a + colon, eg., R3:2. The larger number must be written firsts. Note + that the hardware only supports odd-even pairs, eg., R7:6, R5:4, + R3:2, and R1:0. + + Some instructions (such as -SP (Push Multiple)) require a group of + adjacent registers. Adjacent registers are denoted in the syntax + by the range enclosed in parentheses and separated by a colon, + eg., (R7:3). Again, the larger number appears first. + + Portions of a particular register may be individually specified. + This is written with a dot (".") following the register name and + then a letter denoting the desired portion. For 32-bit registers, + ".H" denotes the most significant ("High") portion. ".L" denotes + the least-significant portion. The subdivisions of the 40-bit + registers are described later. + +`Accumulators' + The set of 40-bit registers A1 and A0 that normally contain data + that is being manipulated. Each accumulator can be accessed in + four ways. + + `one 40-bit register' + The register will be referred to as A1 or A0. + + `one 32-bit register' + The registers are designated as A1.W or A0.W. + + `two 16-bit registers' + The registers are designated as A1.H, A1.L, A0.H or A0.L. + + `one 8-bit register' + The registers are designated as A1.X or A0.X for the bits that + extend beyond bit 31. + +`Data Registers' + The set of 32-bit registers (R0, R1, R2, R3, R4, R5, R6 and R7) + that normally contain data for manipulation. These are + abbreviated as D-register or Dreg. Data registers can be accessed + as 32-bit registers or as two independent 16-bit registers. The + least significant 16 bits of each register is called the "low" + half and is designated with ".L" following the register name. The + most significant 16 bits are called the "high" half and is + designated with ".H" following the name. + + R7.L, r2.h, r4.L, R0.H + +`Pointer Registers' + The set of 32-bit registers (P0, P1, P2, P3, P4, P5, SP and FP) + that normally contain byte addresses of data structures. These are + abbreviated as P-register or Preg. + + p2, p5, fp, sp + +`Stack Pointer SP' + The stack pointer contains the 32-bit address of the last occupied + byte location in the stack. The stack grows by decrementing the + stack pointer. + +`Frame Pointer FP' + The frame pointer contains the 32-bit address of the previous frame + pointer in the stack. It is located at the top of a frame. + +`Loop Top' + LT0 and LT1. These registers contain the 32-bit address of the + top of a zero overhead loop. + +`Loop Count' + LC0 and LC1. These registers contain the 32-bit counter of the + zero overhead loop executions. + +`Loop Bottom' + LB0 and LB1. These registers contain the 32-bit address of the + bottom of a zero overhead loop. + +`Index Registers' + The set of 32-bit registers (I0, I1, I2, I3) that normally contain + byte addresses of data structures. Abbreviated I-register or Ireg. + +`Modify Registers' + The set of 32-bit registers (M0, M1, M2, M3) that normally contain + offset values that are added and subracted to one of the index + registers. Abbreviated as Mreg. + +`Length Registers' + The set of 32-bit registers (L0, L1, L2, L3) that normally contain + the length in bytes of the circular buffer. Abbreviated as Lreg. + Clear the Lreg to disable circular addressing for the + corresponding Ireg. + +`Base Registers' + The set of 32-bit registers (B0, B1, B2, B3) that normally contain + the base address in bytes of the circular buffer. Abbreviated as + Breg. + +`Floating Point' + The Blackfin family has no hardware floating point but the .float + directive generates ieee floating point numbers for use with + software floating point libraries. + +`Blackfin Opcodes' + For detailed information on the Blackfin machine instruction set, + see the Blackfin(r) Processor Instruction Set Reference. + + + +File: as.info, Node: Blackfin Directives, Prev: Blackfin Syntax, Up: Blackfin-Dependent + +9.5.3 Directives +---------------- + +The following directives are provided for compatibility with the VDSP +assembler. + +`.byte2' + Initializes a four byte data object. + +`.byte4' + Initializes a two byte data object. + +`.db' + TBD + +`.dd' + TBD + +`.dw' + TBD + +`.var' + Define and initialize a 32 bit data object. + + +File: as.info, Node: CR16-Dependent, Next: CRIS-Dependent, Prev: Blackfin-Dependent, Up: Machine Dependencies + +9.6 CR16 Dependent Features +=========================== + +* Menu: + +* CR16 Operand Qualifiers:: CR16 Machine Operand Qualifiers + + +File: as.info, Node: CR16 Operand Qualifiers, Up: CR16-Dependent + +9.6.1 CR16 Operand Qualifiers +----------------------------- + +The National Semiconductor CR16 target of `as' has a few machine +dependent operand qualifiers. + + Operand expression type qualifier is an optional field in the +instruction operand, to determines the type of the expression field of +an operand. The `@' is required. CR16 architecture uses one of the +following expression qualifiers: + +`s' + - `Specifies expression operand type as small' + +`m' + - `Specifies expression operand type as medium' + +`l' + - `Specifies expression operand type as large' + +`c' + - `Specifies the CR16 Assembler generates a relocation entry for + the operand, where pc has implied bit, the expression is adjusted + accordingly. The linker uses the relocation entry to update the + operand address at link time.' + +`got/GOT' + - `Specifies the CR16 Assembler generates a relocation entry for + the operand, offset from Global Offset Table. The linker uses this + relocation entry to update the operand address at link time' + +`cgot/cGOT' + - `Specifies the CompactRISC Assembler generates a relocation + entry for the operand, where pc has implied bit, the expression is + adjusted accordingly. The linker uses the relocation entry to + update the operand address at link time.' + + CR16 target operand qualifiers and its size (in bits): + +`Immediate Operand' + - s --- 4 bits + +`' + - m --- 16 bits, for movb and movw instructions. + +`' + - m --- 20 bits, movd instructions. + +`' + - l --- 32 bits + +`Absolute Operand' + - s --- Illegal specifier for this operand. + +`' + - m --- 20 bits, movd instructions. + +`Displacement Operand' + - s --- 8 bits + +`' + - m --- 16 bits + +`' + - l --- 24 bits + + For example: + 1 `movw $_myfun@c,r1' + + This loads the address of _myfun, shifted right by 1, into r1. + + 2 `movd $_myfun@c,(r2,r1)' + + This loads the address of _myfun, shifted right by 1, into register-pair r2-r1. + + 3 `_myfun_ptr:' + `.long _myfun@c' + `loadd _myfun_ptr, (r1,r0)' + `jal (r1,r0)' + + This .long directive, the address of _myfunc, shifted right by 1 at link time. + + 4 `loadd _data1@GOT(r12), (r1,r0)' + + This loads the address of _data1, into global offset table (ie GOT) and its offset value from GOT loads into register-pair r2-r1. + + 5 `loadd _myfunc@cGOT(r12), (r1,r0)' + + This loads the address of _myfun, shifted right by 1, into global offset table (ie GOT) and its offset value from GOT loads into register-pair r1-r0. + + +File: as.info, Node: CRIS-Dependent, Next: D10V-Dependent, Prev: CR16-Dependent, Up: Machine Dependencies + +9.7 CRIS Dependent Features +=========================== + +* Menu: + +* CRIS-Opts:: Command-line Options +* CRIS-Expand:: Instruction expansion +* CRIS-Symbols:: Symbols +* CRIS-Syntax:: Syntax + + +File: as.info, Node: CRIS-Opts, Next: CRIS-Expand, Up: CRIS-Dependent + +9.7.1 Command-line Options +-------------------------- + +The CRIS version of `as' has these machine-dependent command-line +options. + + The format of the generated object files can be either ELF or a.out, +specified by the command-line options `--emulation=crisaout' and +`--emulation=criself'. The default is ELF (criself), unless `as' has +been configured specifically for a.out by using the configuration name +`cris-axis-aout'. + + There are two different link-incompatible ELF object file variants +for CRIS, for use in environments where symbols are expected to be +prefixed by a leading `_' character and for environments without such a +symbol prefix. The variant used for GNU/Linux port has no symbol +prefix. Which variant to produce is specified by either of the options +`--underscore' and `--no-underscore'. The default is `--underscore'. +Since symbols in CRIS a.out objects are expected to have a `_' prefix, +specifying `--no-underscore' when generating a.out objects is an error. +Besides the object format difference, the effect of this option is to +parse register names differently (*note crisnous::). The +`--no-underscore' option makes a `$' register prefix mandatory. + + The option `--pic' must be passed to `as' in order to recognize the +symbol syntax used for ELF (SVR4 PIC) position-independent-code (*note +crispic::). This will also affect expansion of instructions. The +expansion with `--pic' will use PC-relative rather than (slightly +faster) absolute addresses in those expansions. + + The option `--march=ARCHITECTURE' specifies the recognized +instruction set and recognized register names. It also controls the +architecture type of the object file. Valid values for ARCHITECTURE +are: +`v0_v10' + All instructions and register names for any architecture variant + in the set v0...v10 are recognized. This is the default if the + target is configured as cris-*. + +`v10' + Only instructions and register names for CRIS v10 (as found in + ETRAX 100 LX) are recognized. This is the default if the target + is configured as crisv10-*. + +`v32' + Only instructions and register names for CRIS v32 (code name + Guinness) are recognized. This is the default if the target is + configured as crisv32-*. This value implies `--no-mul-bug-abort'. + (A subsequent `--mul-bug-abort' will turn it back on.) + +`common_v10_v32' + Only instructions with register names and addressing modes with + opcodes common to the v10 and v32 are recognized. + + When `-N' is specified, `as' will emit a warning when a 16-bit +branch instruction is expanded into a 32-bit multiple-instruction +construct (*note CRIS-Expand::). + + Some versions of the CRIS v10, for example in the Etrax 100 LX, +contain a bug that causes destabilizing memory accesses when a multiply +instruction is executed with certain values in the first operand just +before a cache-miss. When the `--mul-bug-abort' command line option is +active (the default value), `as' will refuse to assemble a file +containing a multiply instruction at a dangerous offset, one that could +be the last on a cache-line, or is in a section with insufficient +alignment. This placement checking does not catch any case where the +multiply instruction is dangerously placed because it is located in a +delay-slot. The `--mul-bug-abort' command line option turns off the +checking. + + +File: as.info, Node: CRIS-Expand, Next: CRIS-Symbols, Prev: CRIS-Opts, Up: CRIS-Dependent + +9.7.2 Instruction expansion +--------------------------- + +`as' will silently choose an instruction that fits the operand size for +`[register+constant]' operands. For example, the offset `127' in +`move.d [r3+127],r4' fits in an instruction using a signed-byte offset. +Similarly, `move.d [r2+32767],r1' will generate an instruction using a +16-bit offset. For symbolic expressions and constants that do not fit +in 16 bits including the sign bit, a 32-bit offset is generated. + + For branches, `as' will expand from a 16-bit branch instruction into +a sequence of instructions that can reach a full 32-bit address. Since +this does not correspond to a single instruction, such expansions can +optionally be warned about. *Note CRIS-Opts::. + + If the operand is found to fit the range, a `lapc' mnemonic will +translate to a `lapcq' instruction. Use `lapc.d' to force the 32-bit +`lapc' instruction. + + Similarly, the `addo' mnemonic will translate to the shortest +fitting instruction of `addoq', `addo.w' and `addo.d', when used with a +operand that is a constant known at assembly time. + + +File: as.info, Node: CRIS-Symbols, Next: CRIS-Syntax, Prev: CRIS-Expand, Up: CRIS-Dependent + +9.7.3 Symbols +------------- + +Some symbols are defined by the assembler. They're intended to be used +in conditional assembly, for example: + .if ..asm.arch.cris.v32 + CODE FOR CRIS V32 + .elseif ..asm.arch.cris.common_v10_v32 + CODE COMMON TO CRIS V32 AND CRIS V10 + .elseif ..asm.arch.cris.v10 | ..asm.arch.cris.any_v0_v10 + CODE FOR V10 + .else + .error "Code needs to be added here." + .endif + + These symbols are defined in the assembler, reflecting command-line +options, either when specified or the default. They are always +defined, to 0 or 1. +`..asm.arch.cris.any_v0_v10' + This symbol is non-zero when `--march=v0_v10' is specified or the + default. + +`..asm.arch.cris.common_v10_v32' + Set according to the option `--march=common_v10_v32'. + +`..asm.arch.cris.v10' + Reflects the option `--march=v10'. + +`..asm.arch.cris.v32' + Corresponds to `--march=v10'. + + Speaking of symbols, when a symbol is used in code, it can have a +suffix modifying its value for use in position-independent code. *Note +CRIS-Pic::. + + +File: as.info, Node: CRIS-Syntax, Prev: CRIS-Symbols, Up: CRIS-Dependent + +9.7.4 Syntax +------------ + +There are different aspects of the CRIS assembly syntax. + +* Menu: + +* CRIS-Chars:: Special Characters +* CRIS-Pic:: Position-Independent Code Symbols +* CRIS-Regs:: Register Names +* CRIS-Pseudos:: Assembler Directives + + +File: as.info, Node: CRIS-Chars, Next: CRIS-Pic, Up: CRIS-Syntax + +9.7.4.1 Special Characters +.......................... + +The character `#' is a line comment character. It starts a comment if +and only if it is placed at the beginning of a line. + + A `;' character starts a comment anywhere on the line, causing all +characters up to the end of the line to be ignored. + + A `@' character is handled as a line separator equivalent to a +logical new-line character (except in a comment), so separate +instructions can be specified on a single line. + + +File: as.info, Node: CRIS-Pic, Next: CRIS-Regs, Prev: CRIS-Chars, Up: CRIS-Syntax + +9.7.4.2 Symbols in position-independent code +............................................ + +When generating position-independent code (SVR4 PIC) for use in +cris-axis-linux-gnu or crisv32-axis-linux-gnu shared libraries, symbol +suffixes are used to specify what kind of run-time symbol lookup will +be used, expressed in the object as different _relocation types_. +Usually, all absolute symbol values must be located in a table, the +_global offset table_, leaving the code position-independent; +independent of values of global symbols and independent of the address +of the code. The suffix modifies the value of the symbol, into for +example an index into the global offset table where the real symbol +value is entered, or a PC-relative value, or a value relative to the +start of the global offset table. All symbol suffixes start with the +character `:' (omitted in the list below). Every symbol use in code or +a read-only section must therefore have a PIC suffix to enable a useful +shared library to be created. Usually, these constructs must not be +used with an additive constant offset as is usually allowed, i.e. no 4 +as in `symbol + 4' is allowed. This restriction is checked at +link-time, not at assembly-time. + +`GOT' + Attaching this suffix to a symbol in an instruction causes the + symbol to be entered into the global offset table. The value is a + 32-bit index for that symbol into the global offset table. The + name of the corresponding relocation is `R_CRIS_32_GOT'. Example: + `move.d [$r0+extsym:GOT],$r9' + +`GOT16' + Same as for `GOT', but the value is a 16-bit index into the global + offset table. The corresponding relocation is `R_CRIS_16_GOT'. + Example: `move.d [$r0+asymbol:GOT16],$r10' + +`PLT' + This suffix is used for function symbols. It causes a _procedure + linkage table_, an array of code stubs, to be created at the time + the shared object is created or linked against, together with a + global offset table entry. The value is a pc-relative offset to + the corresponding stub code in the procedure linkage table. This + arrangement causes the run-time symbol resolver to be called to + look up and set the value of the symbol the first time the + function is called (at latest; depending environment variables). + It is only safe to leave the symbol unresolved this way if all + references are function calls. The name of the relocation is + `R_CRIS_32_PLT_PCREL'. Example: `add.d fnname:PLT,$pc' + +`PLTG' + Like PLT, but the value is relative to the beginning of the global + offset table. The relocation is `R_CRIS_32_PLT_GOTREL'. Example: + `move.d fnname:PLTG,$r3' + +`GOTPLT' + Similar to `PLT', but the value of the symbol is a 32-bit index + into the global offset table. This is somewhat of a mix between + the effect of the `GOT' and the `PLT' suffix; the difference to + `GOT' is that there will be a procedure linkage table entry + created, and that the symbol is assumed to be a function entry and + will be resolved by the run-time resolver as with `PLT'. The + relocation is `R_CRIS_32_GOTPLT'. Example: `jsr + [$r0+fnname:GOTPLT]' + +`GOTPLT16' + A variant of `GOTPLT' giving a 16-bit value. Its relocation name + is `R_CRIS_16_GOTPLT'. Example: `jsr [$r0+fnname:GOTPLT16]' + +`GOTOFF' + This suffix must only be attached to a local symbol, but may be + used in an expression adding an offset. The value is the address + of the symbol relative to the start of the global offset table. + The relocation name is `R_CRIS_32_GOTREL'. Example: `move.d + [$r0+localsym:GOTOFF],r3' + + +File: as.info, Node: CRIS-Regs, Next: CRIS-Pseudos, Prev: CRIS-Pic, Up: CRIS-Syntax + +9.7.4.3 Register names +...................... + +A `$' character may always prefix a general or special register name in +an instruction operand but is mandatory when the option +`--no-underscore' is specified or when the `.syntax register_prefix' +directive is in effect (*note crisnous::). Register names are +case-insensitive. + + +File: as.info, Node: CRIS-Pseudos, Prev: CRIS-Regs, Up: CRIS-Syntax + +9.7.4.4 Assembler Directives +............................ + +There are a few CRIS-specific pseudo-directives in addition to the +generic ones. *Note Pseudo Ops::. Constants emitted by +pseudo-directives are in little-endian order for CRIS. There is no +support for floating-point-specific directives for CRIS. + +`.dword EXPRESSIONS' + The `.dword' directive is a synonym for `.int', expecting zero or + more EXPRESSIONS, separated by commas. For each expression, a + 32-bit little-endian constant is emitted. + +`.syntax ARGUMENT' + The `.syntax' directive takes as ARGUMENT one of the following + case-sensitive choices. + + `no_register_prefix' + The `.syntax no_register_prefix' directive makes a `$' + character prefix on all registers optional. It overrides a + previous setting, including the corresponding effect of the + option `--no-underscore'. If this directive is used when + ordinary symbols do not have a `_' character prefix, care + must be taken to avoid ambiguities whether an operand is a + register or a symbol; using symbols with names the same as + general or special registers then invoke undefined behavior. + + `register_prefix' + This directive makes a `$' character prefix on all registers + mandatory. It overrides a previous setting, including the + corresponding effect of the option `--underscore'. + + `leading_underscore' + This is an assertion directive, emitting an error if the + `--no-underscore' option is in effect. + + `no_leading_underscore' + This is the opposite of the `.syntax leading_underscore' + directive and emits an error if the option `--underscore' is + in effect. + +`.arch ARGUMENT' + This is an assertion directive, giving an error if the specified + ARGUMENT is not the same as the specified or default value for the + `--march=ARCHITECTURE' option (*note march-option::). + + + +File: as.info, Node: D10V-Dependent, Next: D30V-Dependent, Prev: CRIS-Dependent, Up: Machine Dependencies + +9.8 D10V Dependent Features +=========================== + +* Menu: + +* D10V-Opts:: D10V Options +* D10V-Syntax:: Syntax +* D10V-Float:: Floating Point +* D10V-Opcodes:: Opcodes + + +File: as.info, Node: D10V-Opts, Next: D10V-Syntax, Up: D10V-Dependent + +9.8.1 D10V Options +------------------ + +The Mitsubishi D10V version of `as' has a few machine dependent options. + +`-O' + The D10V can often execute two sub-instructions in parallel. When + this option is used, `as' will attempt to optimize its output by + detecting when instructions can be executed in parallel. + +`--nowarnswap' + To optimize execution performance, `as' will sometimes swap the + order of instructions. Normally this generates a warning. When + this option is used, no warning will be generated when + instructions are swapped. + +`--gstabs-packing' + +`--no-gstabs-packing' + `as' packs adjacent short instructions into a single packed + instruction. `--no-gstabs-packing' turns instruction packing off if + `--gstabs' is specified as well; `--gstabs-packing' (the default) + turns instruction packing on even when `--gstabs' is specified. + + +File: as.info, Node: D10V-Syntax, Next: D10V-Float, Prev: D10V-Opts, Up: D10V-Dependent + +9.8.2 Syntax +------------ + +The D10V syntax is based on the syntax in Mitsubishi's D10V +architecture manual. The differences are detailed below. + +* Menu: + +* D10V-Size:: Size Modifiers +* D10V-Subs:: Sub-Instructions +* D10V-Chars:: Special Characters +* D10V-Regs:: Register Names +* D10V-Addressing:: Addressing Modes +* D10V-Word:: @WORD Modifier + + +File: as.info, Node: D10V-Size, Next: D10V-Subs, Up: D10V-Syntax + +9.8.2.1 Size Modifiers +...................... + +The D10V version of `as' uses the instruction names in the D10V +Architecture Manual. However, the names in the manual are sometimes +ambiguous. There are instruction names that can assemble to a short or +long form opcode. How does the assembler pick the correct form? `as' +will always pick the smallest form if it can. When dealing with a +symbol that is not defined yet when a line is being assembled, it will +always use the long form. If you need to force the assembler to use +either the short or long form of the instruction, you can append either +`.s' (short) or `.l' (long) to it. For example, if you are writing an +assembly program and you want to do a branch to a symbol that is +defined later in your program, you can write `bra.s foo'. Objdump +and GDB will always append `.s' or `.l' to instructions which have both +short and long forms. + + +File: as.info, Node: D10V-Subs, Next: D10V-Chars, Prev: D10V-Size, Up: D10V-Syntax + +9.8.2.2 Sub-Instructions +........................ + +The D10V assembler takes as input a series of instructions, either +one-per-line, or in the special two-per-line format described in the +next section. Some of these instructions will be short-form or +sub-instructions. These sub-instructions can be packed into a single +instruction. The assembler will do this automatically. It will also +detect when it should not pack instructions. For example, when a label +is defined, the next instruction will never be packaged with the +previous one. Whenever a branch and link instruction is called, it +will not be packaged with the next instruction so the return address +will be valid. Nops are automatically inserted when necessary. + + If you do not want the assembler automatically making these +decisions, you can control the packaging and execution type (parallel +or sequential) with the special execution symbols described in the next +section. + + +File: as.info, Node: D10V-Chars, Next: D10V-Regs, Prev: D10V-Subs, Up: D10V-Syntax + +9.8.2.3 Special Characters +.......................... + +`;' and `#' are the line comment characters. Sub-instructions may be +executed in order, in reverse-order, or in parallel. Instructions +listed in the standard one-per-line format will be executed +sequentially. To specify the executing order, use the following +symbols: +`->' + Sequential with instruction on the left first. + +`<-' + Sequential with instruction on the right first. + +`||' + Parallel + The D10V syntax allows either one instruction per line, one +instruction per line with the execution symbol, or two instructions per +line. For example +`abs a1 -> abs r0' + Execute these sequentially. The instruction on the right is in + the right container and is executed second. + +`abs r0 <- abs a1' + Execute these reverse-sequentially. The instruction on the right + is in the right container, and is executed first. + +`ld2w r2,@r8+ || mac a0,r0,r7' + Execute these in parallel. + +`ld2w r2,@r8+ ||' +`mac a0,r0,r7' + Two-line format. Execute these in parallel. + +`ld2w r2,@r8+' +`mac a0,r0,r7' + Two-line format. Execute these sequentially. Assembler will put + them in the proper containers. + +`ld2w r2,@r8+ ->' +`mac a0,r0,r7' + Two-line format. Execute these sequentially. Same as above but + second instruction will always go into right container. + Since `$' has no special meaning, you may use it in symbol names. + + +File: as.info, Node: D10V-Regs, Next: D10V-Addressing, Prev: D10V-Chars, Up: D10V-Syntax + +9.8.2.4 Register Names +...................... + +You can use the predefined symbols `r0' through `r15' to refer to the +D10V registers. You can also use `sp' as an alias for `r15'. The +accumulators are `a0' and `a1'. There are special register-pair names +that may optionally be used in opcodes that require even-numbered +registers. Register names are not case sensitive. + + Register Pairs +`r0-r1' + +`r2-r3' + +`r4-r5' + +`r6-r7' + +`r8-r9' + +`r10-r11' + +`r12-r13' + +`r14-r15' + + The D10V also has predefined symbols for these control registers and +status bits: +`psw' + Processor Status Word + +`bpsw' + Backup Processor Status Word + +`pc' + Program Counter + +`bpc' + Backup Program Counter + +`rpt_c' + Repeat Count + +`rpt_s' + Repeat Start address + +`rpt_e' + Repeat End address + +`mod_s' + Modulo Start address + +`mod_e' + Modulo End address + +`iba' + Instruction Break Address + +`f0' + Flag 0 + +`f1' + Flag 1 + +`c' + Carry flag + + +File: as.info, Node: D10V-Addressing, Next: D10V-Word, Prev: D10V-Regs, Up: D10V-Syntax + +9.8.2.5 Addressing Modes +........................ + +`as' understands the following addressing modes for the D10V. `RN' in +the following refers to any of the numbered registers, but _not_ the +control registers. +`RN' + Register direct + +`@RN' + Register indirect + +`@RN+' + Register indirect with post-increment + +`@RN-' + Register indirect with post-decrement + +`@-SP' + Register indirect with pre-decrement + +`@(DISP, RN)' + Register indirect with displacement + +`ADDR' + PC relative address (for branch or rep). + +`#IMM' + Immediate data (the `#' is optional and ignored) + + +File: as.info, Node: D10V-Word, Prev: D10V-Addressing, Up: D10V-Syntax + +9.8.2.6 @WORD Modifier +...................... + +Any symbol followed by `@word' will be replaced by the symbol's value +shifted right by 2. This is used in situations such as loading a +register with the address of a function (or any other code fragment). +For example, if you want to load a register with the location of the +function `main' then jump to that function, you could do it as follows: + ldi r2, main@word + jmp r2 + + +File: as.info, Node: D10V-Float, Next: D10V-Opcodes, Prev: D10V-Syntax, Up: D10V-Dependent + +9.8.3 Floating Point +-------------------- + +The D10V has no hardware floating point, but the `.float' and `.double' +directives generates IEEE floating-point numbers for compatibility with +other development tools. + + +File: as.info, Node: D10V-Opcodes, Prev: D10V-Float, Up: D10V-Dependent + +9.8.4 Opcodes +------------- + +For detailed information on the D10V machine instruction set, see `D10V +Architecture: A VLIW Microprocessor for Multimedia Applications' +(Mitsubishi Electric Corp.). `as' implements all the standard D10V +opcodes. The only changes are those described in the section on size +modifiers + + +File: as.info, Node: D30V-Dependent, Next: H8/300-Dependent, Prev: D10V-Dependent, Up: Machine Dependencies + +9.9 D30V Dependent Features +=========================== + +* Menu: + +* D30V-Opts:: D30V Options +* D30V-Syntax:: Syntax +* D30V-Float:: Floating Point +* D30V-Opcodes:: Opcodes + + +File: as.info, Node: D30V-Opts, Next: D30V-Syntax, Up: D30V-Dependent + +9.9.1 D30V Options +------------------ + +The Mitsubishi D30V version of `as' has a few machine dependent options. + +`-O' + The D30V can often execute two sub-instructions in parallel. When + this option is used, `as' will attempt to optimize its output by + detecting when instructions can be executed in parallel. + +`-n' + When this option is used, `as' will issue a warning every time it + adds a nop instruction. + +`-N' + When this option is used, `as' will issue a warning if it needs to + insert a nop after a 32-bit multiply before a load or 16-bit + multiply instruction. + + +File: as.info, Node: D30V-Syntax, Next: D30V-Float, Prev: D30V-Opts, Up: D30V-Dependent + +9.9.2 Syntax +------------ + +The D30V syntax is based on the syntax in Mitsubishi's D30V +architecture manual. The differences are detailed below. + +* Menu: + +* D30V-Size:: Size Modifiers +* D30V-Subs:: Sub-Instructions +* D30V-Chars:: Special Characters +* D30V-Guarded:: Guarded Execution +* D30V-Regs:: Register Names +* D30V-Addressing:: Addressing Modes + + +File: as.info, Node: D30V-Size, Next: D30V-Subs, Up: D30V-Syntax + +9.9.2.1 Size Modifiers +...................... + +The D30V version of `as' uses the instruction names in the D30V +Architecture Manual. However, the names in the manual are sometimes +ambiguous. There are instruction names that can assemble to a short or +long form opcode. How does the assembler pick the correct form? `as' +will always pick the smallest form if it can. When dealing with a +symbol that is not defined yet when a line is being assembled, it will +always use the long form. If you need to force the assembler to use +either the short or long form of the instruction, you can append either +`.s' (short) or `.l' (long) to it. For example, if you are writing an +assembly program and you want to do a branch to a symbol that is +defined later in your program, you can write `bra.s foo'. Objdump and +GDB will always append `.s' or `.l' to instructions which have both +short and long forms. + + +File: as.info, Node: D30V-Subs, Next: D30V-Chars, Prev: D30V-Size, Up: D30V-Syntax + +9.9.2.2 Sub-Instructions +........................ + +The D30V assembler takes as input a series of instructions, either +one-per-line, or in the special two-per-line format described in the +next section. Some of these instructions will be short-form or +sub-instructions. These sub-instructions can be packed into a single +instruction. The assembler will do this automatically. It will also +detect when it should not pack instructions. For example, when a label +is defined, the next instruction will never be packaged with the +previous one. Whenever a branch and link instruction is called, it +will not be packaged with the next instruction so the return address +will be valid. Nops are automatically inserted when necessary. + + If you do not want the assembler automatically making these +decisions, you can control the packaging and execution type (parallel +or sequential) with the special execution symbols described in the next +section. + + +File: as.info, Node: D30V-Chars, Next: D30V-Guarded, Prev: D30V-Subs, Up: D30V-Syntax + +9.9.2.3 Special Characters +.......................... + +`;' and `#' are the line comment characters. Sub-instructions may be +executed in order, in reverse-order, or in parallel. Instructions +listed in the standard one-per-line format will be executed +sequentially unless you use the `-O' option. + + To specify the executing order, use the following symbols: +`->' + Sequential with instruction on the left first. + +`<-' + Sequential with instruction on the right first. + +`||' + Parallel + + The D30V syntax allows either one instruction per line, one +instruction per line with the execution symbol, or two instructions per +line. For example +`abs r2,r3 -> abs r4,r5' + Execute these sequentially. The instruction on the right is in + the right container and is executed second. + +`abs r2,r3 <- abs r4,r5' + Execute these reverse-sequentially. The instruction on the right + is in the right container, and is executed first. + +`abs r2,r3 || abs r4,r5' + Execute these in parallel. + +`ldw r2,@(r3,r4) ||' +`mulx r6,r8,r9' + Two-line format. Execute these in parallel. + +`mulx a0,r8,r9' +`stw r2,@(r3,r4)' + Two-line format. Execute these sequentially unless `-O' option is + used. If the `-O' option is used, the assembler will determine if + the instructions could be done in parallel (the above two + instructions can be done in parallel), and if so, emit them as + parallel instructions. The assembler will put them in the proper + containers. In the above example, the assembler will put the + `stw' instruction in left container and the `mulx' instruction in + the right container. + +`stw r2,@(r3,r4) ->' +`mulx a0,r8,r9' + Two-line format. Execute the `stw' instruction followed by the + `mulx' instruction sequentially. The first instruction goes in the + left container and the second instruction goes into right + container. The assembler will give an error if the machine + ordering constraints are violated. + +`stw r2,@(r3,r4) <-' +`mulx a0,r8,r9' + Same as previous example, except that the `mulx' instruction is + executed before the `stw' instruction. + + Since `$' has no special meaning, you may use it in symbol names. + + +File: as.info, Node: D30V-Guarded, Next: D30V-Regs, Prev: D30V-Chars, Up: D30V-Syntax + +9.9.2.4 Guarded Execution +......................... + +`as' supports the full range of guarded execution directives for each +instruction. Just append the directive after the instruction proper. +The directives are: + +`/tx' + Execute the instruction if flag f0 is true. + +`/fx' + Execute the instruction if flag f0 is false. + +`/xt' + Execute the instruction if flag f1 is true. + +`/xf' + Execute the instruction if flag f1 is false. + +`/tt' + Execute the instruction if both flags f0 and f1 are true. + +`/tf' + Execute the instruction if flag f0 is true and flag f1 is false. + + +File: as.info, Node: D30V-Regs, Next: D30V-Addressing, Prev: D30V-Guarded, Up: D30V-Syntax + +9.9.2.5 Register Names +...................... + +You can use the predefined symbols `r0' through `r63' to refer to the +D30V registers. You can also use `sp' as an alias for `r63' and `link' +as an alias for `r62'. The accumulators are `a0' and `a1'. + + The D30V also has predefined symbols for these control registers and +status bits: +`psw' + Processor Status Word + +`bpsw' + Backup Processor Status Word + +`pc' + Program Counter + +`bpc' + Backup Program Counter + +`rpt_c' + Repeat Count + +`rpt_s' + Repeat Start address + +`rpt_e' + Repeat End address + +`mod_s' + Modulo Start address + +`mod_e' + Modulo End address + +`iba' + Instruction Break Address + +`f0' + Flag 0 + +`f1' + Flag 1 + +`f2' + Flag 2 + +`f3' + Flag 3 + +`f4' + Flag 4 + +`f5' + Flag 5 + +`f6' + Flag 6 + +`f7' + Flag 7 + +`s' + Same as flag 4 (saturation flag) + +`v' + Same as flag 5 (overflow flag) + +`va' + Same as flag 6 (sticky overflow flag) + +`c' + Same as flag 7 (carry/borrow flag) + +`b' + Same as flag 7 (carry/borrow flag) + + +File: as.info, Node: D30V-Addressing, Prev: D30V-Regs, Up: D30V-Syntax + +9.9.2.6 Addressing Modes +........................ + +`as' understands the following addressing modes for the D30V. `RN' in +the following refers to any of the numbered registers, but _not_ the +control registers. +`RN' + Register direct + +`@RN' + Register indirect + +`@RN+' + Register indirect with post-increment + +`@RN-' + Register indirect with post-decrement + +`@-SP' + Register indirect with pre-decrement + +`@(DISP, RN)' + Register indirect with displacement + +`ADDR' + PC relative address (for branch or rep). + +`#IMM' + Immediate data (the `#' is optional and ignored) + + +File: as.info, Node: D30V-Float, Next: D30V-Opcodes, Prev: D30V-Syntax, Up: D30V-Dependent + +9.9.3 Floating Point +-------------------- + +The D30V has no hardware floating point, but the `.float' and `.double' +directives generates IEEE floating-point numbers for compatibility with +other development tools. + + +File: as.info, Node: D30V-Opcodes, Prev: D30V-Float, Up: D30V-Dependent + +9.9.4 Opcodes +------------- + +For detailed information on the D30V machine instruction set, see `D30V +Architecture: A VLIW Microprocessor for Multimedia Applications' +(Mitsubishi Electric Corp.). `as' implements all the standard D30V +opcodes. The only changes are those described in the section on size +modifiers + + +File: as.info, Node: H8/300-Dependent, Next: HPPA-Dependent, Prev: D30V-Dependent, Up: Machine Dependencies + +9.10 H8/300 Dependent Features +============================== + +* Menu: + +* H8/300 Options:: Options +* H8/300 Syntax:: Syntax +* H8/300 Floating Point:: Floating Point +* H8/300 Directives:: H8/300 Machine Directives +* H8/300 Opcodes:: Opcodes + + +File: as.info, Node: H8/300 Options, Next: H8/300 Syntax, Up: H8/300-Dependent + +9.10.1 Options +-------------- + +The Renesas H8/300 version of `as' has one machine-dependent option: + +`-h-tick-hex' + Support H'00 style hex constants in addition to 0x00 style. + + + +File: as.info, Node: H8/300 Syntax, Next: H8/300 Floating Point, Prev: H8/300 Options, Up: H8/300-Dependent + +9.10.2 Syntax +------------- + +* Menu: + +* H8/300-Chars:: Special Characters +* H8/300-Regs:: Register Names +* H8/300-Addressing:: Addressing Modes + + +File: as.info, Node: H8/300-Chars, Next: H8/300-Regs, Up: H8/300 Syntax + +9.10.2.1 Special Characters +........................... + +`;' is the line comment character. + + `$' can be used instead of a newline to separate statements. +Therefore _you may not use `$' in symbol names_ on the H8/300. + + +File: as.info, Node: H8/300-Regs, Next: H8/300-Addressing, Prev: H8/300-Chars, Up: H8/300 Syntax + +9.10.2.2 Register Names +....................... + +You can use predefined symbols of the form `rNh' and `rNl' to refer to +the H8/300 registers as sixteen 8-bit general-purpose registers. N is +a digit from `0' to `7'); for instance, both `r0h' and `r7l' are valid +register names. + + You can also use the eight predefined symbols `rN' to refer to the +H8/300 registers as 16-bit registers (you must use this form for +addressing). + + On the H8/300H, you can also use the eight predefined symbols `erN' +(`er0' ... `er7') to refer to the 32-bit general purpose registers. + + The two control registers are called `pc' (program counter; a 16-bit +register, except on the H8/300H where it is 24 bits) and `ccr' +(condition code register; an 8-bit register). `r7' is used as the +stack pointer, and can also be called `sp'. + + +File: as.info, Node: H8/300-Addressing, Prev: H8/300-Regs, Up: H8/300 Syntax + +9.10.2.3 Addressing Modes +......................... + +as understands the following addressing modes for the H8/300: +`rN' + Register direct + +`@rN' + Register indirect + +`@(D, rN)' +`@(D:16, rN)' +`@(D:24, rN)' + Register indirect: 16-bit or 24-bit displacement D from register + N. (24-bit displacements are only meaningful on the H8/300H.) + +`@rN+' + Register indirect with post-increment + +`@-rN' + Register indirect with pre-decrement + +``@'AA' +``@'AA:8' +``@'AA:16' +``@'AA:24' + Absolute address `aa'. (The address size `:24' only makes sense + on the H8/300H.) + +`#XX' +`#XX:8' +`#XX:16' +`#XX:32' + Immediate data XX. You may specify the `:8', `:16', or `:32' for + clarity, if you wish; but `as' neither requires this nor uses + it--the data size required is taken from context. + +``@'`@'AA' +``@'`@'AA:8' + Memory indirect. You may specify the `:8' for clarity, if you + wish; but `as' neither requires this nor uses it. + + +File: as.info, Node: H8/300 Floating Point, Next: H8/300 Directives, Prev: H8/300 Syntax, Up: H8/300-Dependent + +9.10.3 Floating Point +--------------------- + +The H8/300 family has no hardware floating point, but the `.float' +directive generates IEEE floating-point numbers for compatibility with +other development tools. + + +File: as.info, Node: H8/300 Directives, Next: H8/300 Opcodes, Prev: H8/300 Floating Point, Up: H8/300-Dependent + +9.10.4 H8/300 Machine Directives +-------------------------------- + +`as' has the following machine-dependent directives for the H8/300: + +`.h8300h' + Recognize and emit additional instructions for the H8/300H + variant, and also make `.int' emit 32-bit numbers rather than the + usual (16-bit) for the H8/300 family. + +`.h8300s' + Recognize and emit additional instructions for the H8S variant, and + also make `.int' emit 32-bit numbers rather than the usual (16-bit) + for the H8/300 family. + +`.h8300hn' + Recognize and emit additional instructions for the H8/300H variant + in normal mode, and also make `.int' emit 32-bit numbers rather + than the usual (16-bit) for the H8/300 family. + +`.h8300sn' + Recognize and emit additional instructions for the H8S variant in + normal mode, and also make `.int' emit 32-bit numbers rather than + the usual (16-bit) for the H8/300 family. + + On the H8/300 family (including the H8/300H) `.word' directives +generate 16-bit numbers. + + +File: as.info, Node: H8/300 Opcodes, Prev: H8/300 Directives, Up: H8/300-Dependent + +9.10.5 Opcodes +-------------- + +For detailed information on the H8/300 machine instruction set, see +`H8/300 Series Programming Manual'. For information specific to the +H8/300H, see `H8/300H Series Programming Manual' (Renesas). + + `as' implements all the standard H8/300 opcodes. No additional +pseudo-instructions are needed on this family. + + The following table summarizes the H8/300 opcodes, and their +arguments. Entries marked `*' are opcodes used only on the H8/300H. + + Legend: + Rs source register + Rd destination register + abs absolute address + imm immediate data + disp:N N-bit displacement from a register + pcrel:N N-bit displacement relative to program counter + + add.b #imm,rd * andc #imm,ccr + add.b rs,rd band #imm,rd + add.w rs,rd band #imm,@rd + * add.w #imm,rd band #imm,@abs:8 + * add.l rs,rd bra pcrel:8 + * add.l #imm,rd * bra pcrel:16 + adds #imm,rd bt pcrel:8 + addx #imm,rd * bt pcrel:16 + addx rs,rd brn pcrel:8 + and.b #imm,rd * brn pcrel:16 + and.b rs,rd bf pcrel:8 + * and.w rs,rd * bf pcrel:16 + * and.w #imm,rd bhi pcrel:8 + * and.l #imm,rd * bhi pcrel:16 + * and.l rs,rd bls pcrel:8 + + * bls pcrel:16 bld #imm,rd + bcc pcrel:8 bld #imm,@rd + * bcc pcrel:16 bld #imm,@abs:8 + bhs pcrel:8 bnot #imm,rd + * bhs pcrel:16 bnot #imm,@rd + bcs pcrel:8 bnot #imm,@abs:8 + * bcs pcrel:16 bnot rs,rd + blo pcrel:8 bnot rs,@rd + * blo pcrel:16 bnot rs,@abs:8 + bne pcrel:8 bor #imm,rd + * bne pcrel:16 bor #imm,@rd + beq pcrel:8 bor #imm,@abs:8 + * beq pcrel:16 bset #imm,rd + bvc pcrel:8 bset #imm,@rd + * bvc pcrel:16 bset #imm,@abs:8 + bvs pcrel:8 bset rs,rd + * bvs pcrel:16 bset rs,@rd + bpl pcrel:8 bset rs,@abs:8 + * bpl pcrel:16 bsr pcrel:8 + bmi pcrel:8 bsr pcrel:16 + * bmi pcrel:16 bst #imm,rd + bge pcrel:8 bst #imm,@rd + * bge pcrel:16 bst #imm,@abs:8 + blt pcrel:8 btst #imm,rd + * blt pcrel:16 btst #imm,@rd + bgt pcrel:8 btst #imm,@abs:8 + * bgt pcrel:16 btst rs,rd + ble pcrel:8 btst rs,@rd + * ble pcrel:16 btst rs,@abs:8 + bclr #imm,rd bxor #imm,rd + bclr #imm,@rd bxor #imm,@rd + bclr #imm,@abs:8 bxor #imm,@abs:8 + bclr rs,rd cmp.b #imm,rd + bclr rs,@rd cmp.b rs,rd + bclr rs,@abs:8 cmp.w rs,rd + biand #imm,rd cmp.w rs,rd + biand #imm,@rd * cmp.w #imm,rd + biand #imm,@abs:8 * cmp.l #imm,rd + bild #imm,rd * cmp.l rs,rd + bild #imm,@rd daa rs + bild #imm,@abs:8 das rs + bior #imm,rd dec.b rs + bior #imm,@rd * dec.w #imm,rd + bior #imm,@abs:8 * dec.l #imm,rd + bist #imm,rd divxu.b rs,rd + bist #imm,@rd * divxu.w rs,rd + bist #imm,@abs:8 * divxs.b rs,rd + bixor #imm,rd * divxs.w rs,rd + bixor #imm,@rd eepmov + bixor #imm,@abs:8 * eepmovw + + * exts.w rd mov.w rs,@abs:16 + * exts.l rd * mov.l #imm,rd + * extu.w rd * mov.l rs,rd + * extu.l rd * mov.l @rs,rd + inc rs * mov.l @(disp:16,rs),rd + * inc.w #imm,rd * mov.l @(disp:24,rs),rd + * inc.l #imm,rd * mov.l @rs+,rd + jmp @rs * mov.l @abs:16,rd + jmp abs * mov.l @abs:24,rd + jmp @@abs:8 * mov.l rs,@rd + jsr @rs * mov.l rs,@(disp:16,rd) + jsr abs * mov.l rs,@(disp:24,rd) + jsr @@abs:8 * mov.l rs,@-rd + ldc #imm,ccr * mov.l rs,@abs:16 + ldc rs,ccr * mov.l rs,@abs:24 + * ldc @abs:16,ccr movfpe @abs:16,rd + * ldc @abs:24,ccr movtpe rs,@abs:16 + * ldc @(disp:16,rs),ccr mulxu.b rs,rd + * ldc @(disp:24,rs),ccr * mulxu.w rs,rd + * ldc @rs+,ccr * mulxs.b rs,rd + * ldc @rs,ccr * mulxs.w rs,rd + * mov.b @(disp:24,rs),rd neg.b rs + * mov.b rs,@(disp:24,rd) * neg.w rs + mov.b @abs:16,rd * neg.l rs + mov.b rs,rd nop + mov.b @abs:8,rd not.b rs + mov.b rs,@abs:8 * not.w rs + mov.b rs,rd * not.l rs + mov.b #imm,rd or.b #imm,rd + mov.b @rs,rd or.b rs,rd + mov.b @(disp:16,rs),rd * or.w #imm,rd + mov.b @rs+,rd * or.w rs,rd + mov.b @abs:8,rd * or.l #imm,rd + mov.b rs,@rd * or.l rs,rd + mov.b rs,@(disp:16,rd) orc #imm,ccr + mov.b rs,@-rd pop.w rs + mov.b rs,@abs:8 * pop.l rs + mov.w rs,@rd push.w rs + * mov.w @(disp:24,rs),rd * push.l rs + * mov.w rs,@(disp:24,rd) rotl.b rs + * mov.w @abs:24,rd * rotl.w rs + * mov.w rs,@abs:24 * rotl.l rs + mov.w rs,rd rotr.b rs + mov.w #imm,rd * rotr.w rs + mov.w @rs,rd * rotr.l rs + mov.w @(disp:16,rs),rd rotxl.b rs + mov.w @rs+,rd * rotxl.w rs + mov.w @abs:16,rd * rotxl.l rs + mov.w rs,@(disp:16,rd) rotxr.b rs + mov.w rs,@-rd * rotxr.w rs + + * rotxr.l rs * stc ccr,@(disp:24,rd) + bpt * stc ccr,@-rd + rte * stc ccr,@abs:16 + rts * stc ccr,@abs:24 + shal.b rs sub.b rs,rd + * shal.w rs sub.w rs,rd + * shal.l rs * sub.w #imm,rd + shar.b rs * sub.l rs,rd + * shar.w rs * sub.l #imm,rd + * shar.l rs subs #imm,rd + shll.b rs subx #imm,rd + * shll.w rs subx rs,rd + * shll.l rs * trapa #imm + shlr.b rs xor #imm,rd + * shlr.w rs xor rs,rd + * shlr.l rs * xor.w #imm,rd + sleep * xor.w rs,rd + stc ccr,rd * xor.l #imm,rd + * stc ccr,@rs * xor.l rs,rd + * stc ccr,@(disp:16,rd) xorc #imm,ccr + + Four H8/300 instructions (`add', `cmp', `mov', `sub') are defined +with variants using the suffixes `.b', `.w', and `.l' to specify the +size of a memory operand. `as' supports these suffixes, but does not +require them; since one of the operands is always a register, `as' can +deduce the correct size. + + For example, since `r0' refers to a 16-bit register, + mov r0,@foo +is equivalent to + mov.w r0,@foo + + If you use the size suffixes, `as' issues a warning when the suffix +and the register size do not match. + + +File: as.info, Node: HPPA-Dependent, Next: ESA/390-Dependent, Prev: H8/300-Dependent, Up: Machine Dependencies + +9.11 HPPA Dependent Features +============================ + +* Menu: + +* HPPA Notes:: Notes +* HPPA Options:: Options +* HPPA Syntax:: Syntax +* HPPA Floating Point:: Floating Point +* HPPA Directives:: HPPA Machine Directives +* HPPA Opcodes:: Opcodes + + +File: as.info, Node: HPPA Notes, Next: HPPA Options, Up: HPPA-Dependent + +9.11.1 Notes +------------ + +As a back end for GNU CC `as' has been throughly tested and should work +extremely well. We have tested it only minimally on hand written +assembly code and no one has tested it much on the assembly output from +the HP compilers. + + The format of the debugging sections has changed since the original +`as' port (version 1.3X) was released; therefore, you must rebuild all +HPPA objects and libraries with the new assembler so that you can debug +the final executable. + + The HPPA `as' port generates a small subset of the relocations +available in the SOM and ELF object file formats. Additional relocation +support will be added as it becomes necessary. + + +File: as.info, Node: HPPA Options, Next: HPPA Syntax, Prev: HPPA Notes, Up: HPPA-Dependent + +9.11.2 Options +-------------- + +`as' has no machine-dependent command-line options for the HPPA. + + +File: as.info, Node: HPPA Syntax, Next: HPPA Floating Point, Prev: HPPA Options, Up: HPPA-Dependent + +9.11.3 Syntax +------------- + +The assembler syntax closely follows the HPPA instruction set reference +manual; assembler directives and general syntax closely follow the HPPA +assembly language reference manual, with a few noteworthy differences. + + First, a colon may immediately follow a label definition. This is +simply for compatibility with how most assembly language programmers +write code. + + Some obscure expression parsing problems may affect hand written +code which uses the `spop' instructions, or code which makes significant +use of the `!' line separator. + + `as' is much less forgiving about missing arguments and other +similar oversights than the HP assembler. `as' notifies you of missing +arguments as syntax errors; this is regarded as a feature, not a bug. + + Finally, `as' allows you to use an external symbol without +explicitly importing the symbol. _Warning:_ in the future this will be +an error for HPPA targets. + + Special characters for HPPA targets include: + + `;' is the line comment character. + + `!' can be used instead of a newline to separate statements. + + Since `$' has no special meaning, you may use it in symbol names. + + +File: as.info, Node: HPPA Floating Point, Next: HPPA Directives, Prev: HPPA Syntax, Up: HPPA-Dependent + +9.11.4 Floating Point +--------------------- + +The HPPA family uses IEEE floating-point numbers. + + +File: as.info, Node: HPPA Directives, Next: HPPA Opcodes, Prev: HPPA Floating Point, Up: HPPA-Dependent + +9.11.5 HPPA Assembler Directives +-------------------------------- + +`as' for the HPPA supports many additional directives for compatibility +with the native assembler. This section describes them only briefly. +For detailed information on HPPA-specific assembler directives, see +`HP9000 Series 800 Assembly Language Reference Manual' (HP 92432-90001). + + `as' does _not_ support the following assembler directives described +in the HP manual: + + .endm .liston + .enter .locct + .leave .macro + .listoff + + Beyond those implemented for compatibility, `as' supports one +additional assembler directive for the HPPA: `.param'. It conveys +register argument locations for static functions. Its syntax closely +follows the `.export' directive. + + These are the additional directives in `as' for the HPPA: + +`.block N' +`.blockz N' + Reserve N bytes of storage, and initialize them to zero. + +`.call' + Mark the beginning of a procedure call. Only the special case + with _no arguments_ is allowed. + +`.callinfo [ PARAM=VALUE, ... ] [ FLAG, ... ]' + Specify a number of parameters and flags that define the + environment for a procedure. + + PARAM may be any of `frame' (frame size), `entry_gr' (end of + general register range), `entry_fr' (end of float register range), + `entry_sr' (end of space register range). + + The values for FLAG are `calls' or `caller' (proc has + subroutines), `no_calls' (proc does not call subroutines), + `save_rp' (preserve return pointer), `save_sp' (proc preserves + stack pointer), `no_unwind' (do not unwind this proc), `hpux_int' + (proc is interrupt routine). + +`.code' + Assemble into the standard section called `$TEXT$', subsection + `$CODE$'. + +`.copyright "STRING"' + In the SOM object format, insert STRING into the object code, + marked as a copyright string. + +`.copyright "STRING"' + In the ELF object format, insert STRING into the object code, + marked as a version string. + +`.enter' + Not yet supported; the assembler rejects programs containing this + directive. + +`.entry' + Mark the beginning of a procedure. + +`.exit' + Mark the end of a procedure. + +`.export NAME [ ,TYP ] [ ,PARAM=R ]' + Make a procedure NAME available to callers. TYP, if present, must + be one of `absolute', `code' (ELF only, not SOM), `data', `entry', + `data', `entry', `millicode', `plabel', `pri_prog', or `sec_prog'. + + PARAM, if present, provides either relocation information for the + procedure arguments and result, or a privilege level. PARAM may be + `argwN' (where N ranges from `0' to `3', and indicates one of four + one-word arguments); `rtnval' (the procedure's result); or + `priv_lev' (privilege level). For arguments or the result, R + specifies how to relocate, and must be one of `no' (not + relocatable), `gr' (argument is in general register), `fr' (in + floating point register), or `fu' (upper half of float register). + For `priv_lev', R is an integer. + +`.half N' + Define a two-byte integer constant N; synonym for the portable + `as' directive `.short'. + +`.import NAME [ ,TYP ]' + Converse of `.export'; make a procedure available to call. The + arguments use the same conventions as the first two arguments for + `.export'. + +`.label NAME' + Define NAME as a label for the current assembly location. + +`.leave' + Not yet supported; the assembler rejects programs containing this + directive. + +`.origin LC' + Advance location counter to LC. Synonym for the `as' portable + directive `.org'. + +`.param NAME [ ,TYP ] [ ,PARAM=R ]' + Similar to `.export', but used for static procedures. + +`.proc' + Use preceding the first statement of a procedure. + +`.procend' + Use following the last statement of a procedure. + +`LABEL .reg EXPR' + Synonym for `.equ'; define LABEL with the absolute expression EXPR + as its value. + +`.space SECNAME [ ,PARAMS ]' + Switch to section SECNAME, creating a new section by that name if + necessary. You may only use PARAMS when creating a new section, + not when switching to an existing one. SECNAME may identify a + section by number rather than by name. + + If specified, the list PARAMS declares attributes of the section, + identified by keywords. The keywords recognized are `spnum=EXP' + (identify this section by the number EXP, an absolute expression), + `sort=EXP' (order sections according to this sort key when linking; + EXP is an absolute expression), `unloadable' (section contains no + loadable data), `notdefined' (this section defined elsewhere), and + `private' (data in this section not available to other programs). + +`.spnum SECNAM' + Allocate four bytes of storage, and initialize them with the + section number of the section named SECNAM. (You can define the + section number with the HPPA `.space' directive.) + +`.string "STR"' + Copy the characters in the string STR to the object file. *Note + Strings: Strings, for information on escape sequences you can use + in `as' strings. + + _Warning!_ The HPPA version of `.string' differs from the usual + `as' definition: it does _not_ write a zero byte after copying STR. + +`.stringz "STR"' + Like `.string', but appends a zero byte after copying STR to object + file. + +`.subspa NAME [ ,PARAMS ]' +`.nsubspa NAME [ ,PARAMS ]' + Similar to `.space', but selects a subsection NAME within the + current section. You may only specify PARAMS when you create a + subsection (in the first instance of `.subspa' for this NAME). + + If specified, the list PARAMS declares attributes of the + subsection, identified by keywords. The keywords recognized are + `quad=EXPR' ("quadrant" for this subsection), `align=EXPR' + (alignment for beginning of this subsection; a power of two), + `access=EXPR' (value for "access rights" field), `sort=EXPR' + (sorting order for this subspace in link), `code_only' (subsection + contains only code), `unloadable' (subsection cannot be loaded + into memory), `comdat' (subsection is comdat), `common' + (subsection is common block), `dup_comm' (subsection may have + duplicate names), or `zero' (subsection is all zeros, do not write + in object file). + + `.nsubspa' always creates a new subspace with the given name, even + if one with the same name already exists. + + `comdat', `common' and `dup_comm' can be used to implement various + flavors of one-only support when using the SOM linker. The SOM + linker only supports specific combinations of these flags. The + details are not documented. A brief description is provided here. + + `comdat' provides a form of linkonce support. It is useful for + both code and data subspaces. A `comdat' subspace has a key symbol + marked by the `is_comdat' flag or `ST_COMDAT'. Only the first + subspace for any given key is selected. The key symbol becomes + universal in shared links. This is similar to the behavior of + `secondary_def' symbols. + + `common' provides Fortran named common support. It is only useful + for data subspaces. Symbols with the flag `is_common' retain this + flag in shared links. Referencing a `is_common' symbol in a shared + library from outside the library doesn't work. Thus, `is_common' + symbols must be output whenever they are needed. + + `common' and `dup_comm' together provide Cobol common support. + The subspaces in this case must all be the same length. + Otherwise, this support is similar to the Fortran common support. + + `dup_comm' by itself provides a type of one-only support for code. + Only the first `dup_comm' subspace is selected. There is a rather + complex algorithm to compare subspaces. Code symbols marked with + the `dup_common' flag are hidden. This support was intended for + "C++ duplicate inlines". + + A simplified technique is used to mark the flags of symbols based + on the flags of their subspace. A symbol with the scope + SS_UNIVERSAL and type ST_ENTRY, ST_CODE or ST_DATA is marked with + the corresponding settings of `comdat', `common' and `dup_comm' + from the subspace, respectively. This avoids having to introduce + additional directives to mark these symbols. The HP assembler + sets `is_common' from `common'. However, it doesn't set the + `dup_common' from `dup_comm'. It doesn't have `comdat' support. + +`.version "STR"' + Write STR as version identifier in object code. + + +File: as.info, Node: HPPA Opcodes, Prev: HPPA Directives, Up: HPPA-Dependent + +9.11.6 Opcodes +-------------- + +For detailed information on the HPPA machine instruction set, see +`PA-RISC Architecture and Instruction Set Reference Manual' (HP +09740-90039). + + +File: as.info, Node: ESA/390-Dependent, Next: i386-Dependent, Prev: HPPA-Dependent, Up: Machine Dependencies + +9.12 ESA/390 Dependent Features +=============================== + +* Menu: + +* ESA/390 Notes:: Notes +* ESA/390 Options:: Options +* ESA/390 Syntax:: Syntax +* ESA/390 Floating Point:: Floating Point +* ESA/390 Directives:: ESA/390 Machine Directives +* ESA/390 Opcodes:: Opcodes + + +File: as.info, Node: ESA/390 Notes, Next: ESA/390 Options, Up: ESA/390-Dependent + +9.12.1 Notes +------------ + +The ESA/390 `as' port is currently intended to be a back-end for the +GNU CC compiler. It is not HLASM compatible, although it does support +a subset of some of the HLASM directives. The only supported binary +file format is ELF; none of the usual MVS/VM/OE/USS object file +formats, such as ESD or XSD, are supported. + + When used with the GNU CC compiler, the ESA/390 `as' will produce +correct, fully relocated, functional binaries, and has been used to +compile and execute large projects. However, many aspects should still +be considered experimental; these include shared library support, +dynamically loadable objects, and any relocation other than the 31-bit +relocation. + + +File: as.info, Node: ESA/390 Options, Next: ESA/390 Syntax, Prev: ESA/390 Notes, Up: ESA/390-Dependent + +9.12.2 Options +-------------- + +`as' has no machine-dependent command-line options for the ESA/390. + + +File: as.info, Node: ESA/390 Syntax, Next: ESA/390 Floating Point, Prev: ESA/390 Options, Up: ESA/390-Dependent + +9.12.3 Syntax +------------- + +The opcode/operand syntax follows the ESA/390 Principles of Operation +manual; assembler directives and general syntax are loosely based on the +prevailing AT&T/SVR4/ELF/Solaris style notation. HLASM-style directives +are _not_ supported for the most part, with the exception of those +described herein. + + A leading dot in front of directives is optional, and the case of +directives is ignored; thus for example, .using and USING have the same +effect. + + A colon may immediately follow a label definition. This is simply +for compatibility with how most assembly language programmers write +code. + + `#' is the line comment character. + + `;' can be used instead of a newline to separate statements. + + Since `$' has no special meaning, you may use it in symbol names. + + Registers can be given the symbolic names r0..r15, fp0, fp2, fp4, +fp6. By using thesse symbolic names, `as' can detect simple syntax +errors. The name rarg or r.arg is a synonym for r11, rtca or r.tca for +r12, sp, r.sp, dsa r.dsa for r13, lr or r.lr for r14, rbase or r.base +for r3 and rpgt or r.pgt for r4. + + `*' is the current location counter. Unlike `.' it is always +relative to the last USING directive. Note that this means that +expressions cannot use multiplication, as any occurrence of `*' will be +interpreted as a location counter. + + All labels are relative to the last USING. Thus, branches to a label +always imply the use of base+displacement. + + Many of the usual forms of address constants / address literals are +supported. Thus, + .using *,r3 + L r15,=A(some_routine) + LM r6,r7,=V(some_longlong_extern) + A r1,=F'12' + AH r0,=H'42' + ME r6,=E'3.1416' + MD r6,=D'3.14159265358979' + O r6,=XL4'cacad0d0' + .ltorg + should all behave as expected: that is, an entry in the literal pool +will be created (or reused if it already exists), and the instruction +operands will be the displacement into the literal pool using the +current base register (as last declared with the `.using' directive). + + +File: as.info, Node: ESA/390 Floating Point, Next: ESA/390 Directives, Prev: ESA/390 Syntax, Up: ESA/390-Dependent + +9.12.4 Floating Point +--------------------- + +The assembler generates only IEEE floating-point numbers. The older +floating point formats are not supported. + + +File: as.info, Node: ESA/390 Directives, Next: ESA/390 Opcodes, Prev: ESA/390 Floating Point, Up: ESA/390-Dependent + +9.12.5 ESA/390 Assembler Directives +----------------------------------- + +`as' for the ESA/390 supports all of the standard ELF/SVR4 assembler +directives that are documented in the main part of this documentation. +Several additional directives are supported in order to implement the +ESA/390 addressing model. The most important of these are `.using' and +`.ltorg' + + These are the additional directives in `as' for the ESA/390: + +`.dc' + A small subset of the usual DC directive is supported. + +`.drop REGNO' + Stop using REGNO as the base register. The REGNO must have been + previously declared with a `.using' directive in the same section + as the current section. + +`.ebcdic STRING' + Emit the EBCDIC equivalent of the indicated string. The emitted + string will be null terminated. Note that the directives + `.string' etc. emit ascii strings by default. + +`EQU' + The standard HLASM-style EQU directive is not supported; however, + the standard `as' directive .equ can be used to the same effect. + +`.ltorg' + Dump the literal pool accumulated so far; begin a new literal pool. + The literal pool will be written in the current section; in order + to generate correct assembly, a `.using' must have been previously + specified in the same section. + +`.using EXPR,REGNO' + Use REGNO as the base register for all subsequent RX, RS, and SS + form instructions. The EXPR will be evaluated to obtain the base + address; usually, EXPR will merely be `*'. + + This assembler allows two `.using' directives to be simultaneously + outstanding, one in the `.text' section, and one in another section + (typically, the `.data' section). This feature allows dynamically + loaded objects to be implemented in a relatively straightforward + way. A `.using' directive must always be specified in the `.text' + section; this will specify the base register that will be used for + branches in the `.text' section. A second `.using' may be + specified in another section; this will specify the base register + that is used for non-label address literals. When a second + `.using' is specified, then the subsequent `.ltorg' must be put in + the same section; otherwise an error will result. + + Thus, for example, the following code uses `r3' to address branch + targets and `r4' to address the literal pool, which has been + written to the `.data' section. The is, the constants + `=A(some_routine)', `=H'42'' and `=E'3.1416'' will all appear in + the `.data' section. + + .data + .using LITPOOL,r4 + .text + BASR r3,0 + .using *,r3 + B START + .long LITPOOL + START: + L r4,4(,r3) + L r15,=A(some_routine) + LTR r15,r15 + BNE LABEL + AH r0,=H'42' + LABEL: + ME r6,=E'3.1416' + .data + LITPOOL: + .ltorg + + Note that this dual-`.using' directive semantics extends and is + not compatible with HLASM semantics. Note that this assembler + directive does not support the full range of HLASM semantics. + + + +File: as.info, Node: ESA/390 Opcodes, Prev: ESA/390 Directives, Up: ESA/390-Dependent + +9.12.6 Opcodes +-------------- + +For detailed information on the ESA/390 machine instruction set, see +`ESA/390 Principles of Operation' (IBM Publication Number DZ9AR004). + + +File: as.info, Node: i386-Dependent, Next: i860-Dependent, Prev: ESA/390-Dependent, Up: Machine Dependencies + +9.13 80386 Dependent Features +============================= + + The i386 version `as' supports both the original Intel 386 +architecture in both 16 and 32-bit mode as well as AMD x86-64 +architecture extending the Intel architecture to 64-bits. + +* Menu: + +* i386-Options:: Options +* i386-Directives:: X86 specific directives +* i386-Syntax:: AT&T Syntax versus Intel Syntax +* i386-Mnemonics:: Instruction Naming +* i386-Regs:: Register Naming +* i386-Prefixes:: Instruction Prefixes +* i386-Memory:: Memory References +* i386-Jumps:: Handling of Jump Instructions +* i386-Float:: Floating Point +* i386-SIMD:: Intel's MMX and AMD's 3DNow! SIMD Operations +* i386-16bit:: Writing 16-bit Code +* i386-Arch:: Specifying an x86 CPU architecture +* i386-Bugs:: AT&T Syntax bugs +* i386-Notes:: Notes + + +File: as.info, Node: i386-Options, Next: i386-Directives, Up: i386-Dependent + +9.13.1 Options +-------------- + +The i386 version of `as' has a few machine dependent options: + +`--32 | --64' + Select the word size, either 32 bits or 64 bits. Selecting 32-bit + implies Intel i386 architecture, while 64-bit implies AMD x86-64 + architecture. + + These options are only available with the ELF object file format, + and require that the necessary BFD support has been included (on a + 32-bit platform you have to add -enable-64-bit-bfd to configure + enable 64-bit usage and use x86-64 as target platform). + +`-n' + By default, x86 GAS replaces multiple nop instructions used for + alignment within code sections with multi-byte nop instructions + such as leal 0(%esi,1),%esi. This switch disables the + optimization. + +`--divide' + On SVR4-derived platforms, the character `/' is treated as a + comment character, which means that it cannot be used in + expressions. The `--divide' option turns `/' into a normal + character. This does not disable `/' at the beginning of a line + starting a comment, or affect using `#' for starting a comment. + +`-march=CPU[+EXTENSION...]' + This option specifies the target processor. The assembler will + issue an error message if an attempt is made to assemble an + instruction which will not execute on the target processor. The + following processor names are recognized: `i8086', `i186', `i286', + `i386', `i486', `i586', `i686', `pentium', `pentiumpro', + `pentiumii', `pentiumiii', `pentium4', `prescott', `nocona', + `core', `core2', `corei7', `l1om', `k6', `k6_2', `athlon', + `opteron', `k8', `amdfam10', `generic32' and `generic64'. + + In addition to the basic instruction set, the assembler can be + told to accept various extension mnemonics. For example, + `-march=i686+sse4+vmx' extends I686 with SSE4 and VMX. The + following extensions are currently supported: `8087', `287', `387', + `no87', `mmx', `nommx', `sse', `sse2', `sse3', `ssse3', `sse4.1', + `sse4.2', `sse4', `nosse', `avx', `noavx', `vmx', `smx', `xsave', + `aes', `pclmul', `fma', `movbe', `ept', `clflush', `syscall', + `rdtscp', `3dnow', `3dnowa', `sse4a', `sse5', `svme', `abm' and + `padlock'. Note that rather than extending a basic instruction + set, the extension mnemonics starting with `no' revoke the + respective functionality. + + When the `.arch' directive is used with `-march', the `.arch' + directive will take precedent. + +`-mtune=CPU' + This option specifies a processor to optimize for. When used in + conjunction with the `-march' option, only instructions of the + processor specified by the `-march' option will be generated. + + Valid CPU values are identical to the processor list of + `-march=CPU'. + +`-msse2avx' + This option specifies that the assembler should encode SSE + instructions with VEX prefix. + +`-msse-check=NONE' + +`-msse-check=WARNING' + +`-msse-check=ERROR' + These options control if the assembler should check SSE + intructions. `-msse-check=NONE' will make the assembler not to + check SSE instructions, which is the default. + `-msse-check=WARNING' will make the assembler issue a warning for + any SSE intruction. `-msse-check=ERROR' will make the assembler + issue an error for any SSE intruction. + +`-mmnemonic=ATT' + +`-mmnemonic=INTEL' + This option specifies instruction mnemonic for matching + instructions. The `.att_mnemonic' and `.intel_mnemonic' + directives will take precedent. + +`-msyntax=ATT' + +`-msyntax=INTEL' + This option specifies instruction syntax when processing + instructions. The `.att_syntax' and `.intel_syntax' directives + will take precedent. + +`-mnaked-reg' + This opetion specifies that registers don't require a `%' prefix. + The `.att_syntax' and `.intel_syntax' directives will take + precedent. + + + +File: as.info, Node: i386-Directives, Next: i386-Syntax, Prev: i386-Options, Up: i386-Dependent + +9.13.2 x86 specific Directives +------------------------------ + +`.lcomm SYMBOL , LENGTH[, ALIGNMENT]' + Reserve LENGTH (an absolute expression) bytes for a local common + denoted by SYMBOL. The section and value of SYMBOL are those of + the new local common. The addresses are allocated in the bss + section, so that at run-time the bytes start off zeroed. Since + SYMBOL is not declared global, it is normally not visible to `ld'. + The optional third parameter, ALIGNMENT, specifies the desired + alignment of the symbol in the bss section. + + This directive is only available for COFF based x86 targets. + + + +File: as.info, Node: i386-Syntax, Next: i386-Mnemonics, Prev: i386-Directives, Up: i386-Dependent + +9.13.3 AT&T Syntax versus Intel Syntax +-------------------------------------- + +`as' now supports assembly using Intel assembler syntax. +`.intel_syntax' selects Intel mode, and `.att_syntax' switches back to +the usual AT&T mode for compatibility with the output of `gcc'. Either +of these directives may have an optional argument, `prefix', or +`noprefix' specifying whether registers require a `%' prefix. AT&T +System V/386 assembler syntax is quite different from Intel syntax. We +mention these differences because almost all 80386 documents use Intel +syntax. Notable differences between the two syntaxes are: + + * AT&T immediate operands are preceded by `$'; Intel immediate + operands are undelimited (Intel `push 4' is AT&T `pushl $4'). + AT&T register operands are preceded by `%'; Intel register operands + are undelimited. AT&T absolute (as opposed to PC relative) + jump/call operands are prefixed by `*'; they are undelimited in + Intel syntax. + + * AT&T and Intel syntax use the opposite order for source and + destination operands. Intel `add eax, 4' is `addl $4, %eax'. The + `source, dest' convention is maintained for compatibility with + previous Unix assemblers. Note that `bound', `invlpga', and + instructions with 2 immediate operands, such as the `enter' + instruction, do _not_ have reversed order. *Note i386-Bugs::. + + * In AT&T syntax the size of memory operands is determined from the + last character of the instruction mnemonic. Mnemonic suffixes of + `b', `w', `l' and `q' specify byte (8-bit), word (16-bit), long + (32-bit) and quadruple word (64-bit) memory references. Intel + syntax accomplishes this by prefixing memory operands (_not_ the + instruction mnemonics) with `byte ptr', `word ptr', `dword ptr' + and `qword ptr'. Thus, Intel `mov al, byte ptr FOO' is `movb FOO, + %al' in AT&T syntax. + + * Immediate form long jumps and calls are `lcall/ljmp $SECTION, + $OFFSET' in AT&T syntax; the Intel syntax is `call/jmp far + SECTION:OFFSET'. Also, the far return instruction is `lret + $STACK-ADJUST' in AT&T syntax; Intel syntax is `ret far + STACK-ADJUST'. + + * The AT&T assembler does not provide support for multiple section + programs. Unix style systems expect all programs to be single + sections. + + +File: as.info, Node: i386-Mnemonics, Next: i386-Regs, Prev: i386-Syntax, Up: i386-Dependent + +9.13.4 Instruction Naming +------------------------- + +Instruction mnemonics are suffixed with one character modifiers which +specify the size of operands. The letters `b', `w', `l' and `q' +specify byte, word, long and quadruple word operands. If no suffix is +specified by an instruction then `as' tries to fill in the missing +suffix based on the destination register operand (the last one by +convention). Thus, `mov %ax, %bx' is equivalent to `movw %ax, %bx'; +also, `mov $1, %bx' is equivalent to `movw $1, bx'. Note that this is +incompatible with the AT&T Unix assembler which assumes that a missing +mnemonic suffix implies long operand size. (This incompatibility does +not affect compiler output since compilers always explicitly specify +the mnemonic suffix.) + + Almost all instructions have the same names in AT&T and Intel format. +There are a few exceptions. The sign extend and zero extend +instructions need two sizes to specify them. They need a size to +sign/zero extend _from_ and a size to zero extend _to_. This is +accomplished by using two instruction mnemonic suffixes in AT&T syntax. +Base names for sign extend and zero extend are `movs...' and `movz...' +in AT&T syntax (`movsx' and `movzx' in Intel syntax). The instruction +mnemonic suffixes are tacked on to this base name, the _from_ suffix +before the _to_ suffix. Thus, `movsbl %al, %edx' is AT&T syntax for +"move sign extend _from_ %al _to_ %edx." Possible suffixes, thus, are +`bl' (from byte to long), `bw' (from byte to word), `wl' (from word to +long), `bq' (from byte to quadruple word), `wq' (from word to quadruple +word), and `lq' (from long to quadruple word). + + Different encoding options can be specified via optional mnemonic +suffix. `.s' suffix swaps 2 register operands in encoding when moving +from one register to another. + + The Intel-syntax conversion instructions + + * `cbw' -- sign-extend byte in `%al' to word in `%ax', + + * `cwde' -- sign-extend word in `%ax' to long in `%eax', + + * `cwd' -- sign-extend word in `%ax' to long in `%dx:%ax', + + * `cdq' -- sign-extend dword in `%eax' to quad in `%edx:%eax', + + * `cdqe' -- sign-extend dword in `%eax' to quad in `%rax' (x86-64 + only), + + * `cqo' -- sign-extend quad in `%rax' to octuple in `%rdx:%rax' + (x86-64 only), + +are called `cbtw', `cwtl', `cwtd', `cltd', `cltq', and `cqto' in AT&T +naming. `as' accepts either naming for these instructions. + + Far call/jump instructions are `lcall' and `ljmp' in AT&T syntax, +but are `call far' and `jump far' in Intel convention. + +9.13.5 AT&T Mnemonic versus Intel Mnemonic +------------------------------------------ + +`as' supports assembly using Intel mnemonic. `.intel_mnemonic' selects +Intel mnemonic with Intel syntax, and `.att_mnemonic' switches back to +the usual AT&T mnemonic with AT&T syntax for compatibility with the +output of `gcc'. Several x87 instructions, `fadd', `fdiv', `fdivp', +`fdivr', `fdivrp', `fmul', `fsub', `fsubp', `fsubr' and `fsubrp', are +implemented in AT&T System V/386 assembler with different mnemonics +from those in Intel IA32 specification. `gcc' generates those +instructions with AT&T mnemonic. + + +File: as.info, Node: i386-Regs, Next: i386-Prefixes, Prev: i386-Mnemonics, Up: i386-Dependent + +9.13.6 Register Naming +---------------------- + +Register operands are always prefixed with `%'. The 80386 registers +consist of + + * the 8 32-bit registers `%eax' (the accumulator), `%ebx', `%ecx', + `%edx', `%edi', `%esi', `%ebp' (the frame pointer), and `%esp' + (the stack pointer). + + * the 8 16-bit low-ends of these: `%ax', `%bx', `%cx', `%dx', `%di', + `%si', `%bp', and `%sp'. + + * the 8 8-bit registers: `%ah', `%al', `%bh', `%bl', `%ch', `%cl', + `%dh', and `%dl' (These are the high-bytes and low-bytes of `%ax', + `%bx', `%cx', and `%dx') + + * the 6 section registers `%cs' (code section), `%ds' (data + section), `%ss' (stack section), `%es', `%fs', and `%gs'. + + * the 3 processor control registers `%cr0', `%cr2', and `%cr3'. + + * the 6 debug registers `%db0', `%db1', `%db2', `%db3', `%db6', and + `%db7'. + + * the 2 test registers `%tr6' and `%tr7'. + + * the 8 floating point register stack `%st' or equivalently + `%st(0)', `%st(1)', `%st(2)', `%st(3)', `%st(4)', `%st(5)', + `%st(6)', and `%st(7)'. These registers are overloaded by 8 MMX + registers `%mm0', `%mm1', `%mm2', `%mm3', `%mm4', `%mm5', `%mm6' + and `%mm7'. + + * the 8 SSE registers registers `%xmm0', `%xmm1', `%xmm2', `%xmm3', + `%xmm4', `%xmm5', `%xmm6' and `%xmm7'. + + The AMD x86-64 architecture extends the register set by: + + * enhancing the 8 32-bit registers to 64-bit: `%rax' (the + accumulator), `%rbx', `%rcx', `%rdx', `%rdi', `%rsi', `%rbp' (the + frame pointer), `%rsp' (the stack pointer) + + * the 8 extended registers `%r8'-`%r15'. + + * the 8 32-bit low ends of the extended registers: `%r8d'-`%r15d' + + * the 8 16-bit low ends of the extended registers: `%r8w'-`%r15w' + + * the 8 8-bit low ends of the extended registers: `%r8b'-`%r15b' + + * the 4 8-bit registers: `%sil', `%dil', `%bpl', `%spl'. + + * the 8 debug registers: `%db8'-`%db15'. + + * the 8 SSE registers: `%xmm8'-`%xmm15'. + + +File: as.info, Node: i386-Prefixes, Next: i386-Memory, Prev: i386-Regs, Up: i386-Dependent + +9.13.7 Instruction Prefixes +--------------------------- + +Instruction prefixes are used to modify the following instruction. They +are used to repeat string instructions, to provide section overrides, to +perform bus lock operations, and to change operand and address sizes. +(Most instructions that normally operate on 32-bit operands will use +16-bit operands if the instruction has an "operand size" prefix.) +Instruction prefixes are best written on the same line as the +instruction they act upon. For example, the `scas' (scan string) +instruction is repeated with: + + repne scas %es:(%edi),%al + + You may also place prefixes on the lines immediately preceding the +instruction, but this circumvents checks that `as' does with prefixes, +and will not work with all prefixes. + + Here is a list of instruction prefixes: + + * Section override prefixes `cs', `ds', `ss', `es', `fs', `gs'. + These are automatically added by specifying using the + SECTION:MEMORY-OPERAND form for memory references. + + * Operand/Address size prefixes `data16' and `addr16' change 32-bit + operands/addresses into 16-bit operands/addresses, while `data32' + and `addr32' change 16-bit ones (in a `.code16' section) into + 32-bit operands/addresses. These prefixes _must_ appear on the + same line of code as the instruction they modify. For example, in + a 16-bit `.code16' section, you might write: + + addr32 jmpl *(%ebx) + + * The bus lock prefix `lock' inhibits interrupts during execution of + the instruction it precedes. (This is only valid with certain + instructions; see a 80386 manual for details). + + * The wait for coprocessor prefix `wait' waits for the coprocessor to + complete the current instruction. This should never be needed for + the 80386/80387 combination. + + * The `rep', `repe', and `repne' prefixes are added to string + instructions to make them repeat `%ecx' times (`%cx' times if the + current address size is 16-bits). + + * The `rex' family of prefixes is used by x86-64 to encode + extensions to i386 instruction set. The `rex' prefix has four + bits -- an operand size overwrite (`64') used to change operand + size from 32-bit to 64-bit and X, Y and Z extensions bits used to + extend the register set. + + You may write the `rex' prefixes directly. The `rex64xyz' + instruction emits `rex' prefix with all the bits set. By omitting + the `64', `x', `y' or `z' you may write other prefixes as well. + Normally, there is no need to write the prefixes explicitly, since + gas will automatically generate them based on the instruction + operands. + + +File: as.info, Node: i386-Memory, Next: i386-Jumps, Prev: i386-Prefixes, Up: i386-Dependent + +9.13.8 Memory References +------------------------ + +An Intel syntax indirect memory reference of the form + + SECTION:[BASE + INDEX*SCALE + DISP] + +is translated into the AT&T syntax + + SECTION:DISP(BASE, INDEX, SCALE) + +where BASE and INDEX are the optional 32-bit base and index registers, +DISP is the optional displacement, and SCALE, taking the values 1, 2, +4, and 8, multiplies INDEX to calculate the address of the operand. If +no SCALE is specified, SCALE is taken to be 1. SECTION specifies the +optional section register for the memory operand, and may override the +default section register (see a 80386 manual for section register +defaults). Note that section overrides in AT&T syntax _must_ be +preceded by a `%'. If you specify a section override which coincides +with the default section register, `as' does _not_ output any section +register override prefixes to assemble the given instruction. Thus, +section overrides can be specified to emphasize which section register +is used for a given memory operand. + + Here are some examples of Intel and AT&T style memory references: + +AT&T: `-4(%ebp)', Intel: `[ebp - 4]' + BASE is `%ebp'; DISP is `-4'. SECTION is missing, and the default + section is used (`%ss' for addressing with `%ebp' as the base + register). INDEX, SCALE are both missing. + +AT&T: `foo(,%eax,4)', Intel: `[foo + eax*4]' + INDEX is `%eax' (scaled by a SCALE 4); DISP is `foo'. All other + fields are missing. The section register here defaults to `%ds'. + +AT&T: `foo(,1)'; Intel `[foo]' + This uses the value pointed to by `foo' as a memory operand. Note + that BASE and INDEX are both missing, but there is only _one_ `,'. + This is a syntactic exception. + +AT&T: `%gs:foo'; Intel `gs:foo' + This selects the contents of the variable `foo' with section + register SECTION being `%gs'. + + Absolute (as opposed to PC relative) call and jump operands must be +prefixed with `*'. If no `*' is specified, `as' always chooses PC +relative addressing for jump/call labels. + + Any instruction that has a memory operand, but no register operand, +_must_ specify its size (byte, word, long, or quadruple) with an +instruction mnemonic suffix (`b', `w', `l' or `q', respectively). + + The x86-64 architecture adds an RIP (instruction pointer relative) +addressing. This addressing mode is specified by using `rip' as a base +register. Only constant offsets are valid. For example: + +AT&T: `1234(%rip)', Intel: `[rip + 1234]' + Points to the address 1234 bytes past the end of the current + instruction. + +AT&T: `symbol(%rip)', Intel: `[rip + symbol]' + Points to the `symbol' in RIP relative way, this is shorter than + the default absolute addressing. + + Other addressing modes remain unchanged in x86-64 architecture, +except registers used are 64-bit instead of 32-bit. + + +File: as.info, Node: i386-Jumps, Next: i386-Float, Prev: i386-Memory, Up: i386-Dependent + +9.13.9 Handling of Jump Instructions +------------------------------------ + +Jump instructions are always optimized to use the smallest possible +displacements. This is accomplished by using byte (8-bit) displacement +jumps whenever the target is sufficiently close. If a byte displacement +is insufficient a long displacement is used. We do not support word +(16-bit) displacement jumps in 32-bit mode (i.e. prefixing the jump +instruction with the `data16' instruction prefix), since the 80386 +insists upon masking `%eip' to 16 bits after the word displacement is +added. (See also *note i386-Arch::) + + Note that the `jcxz', `jecxz', `loop', `loopz', `loope', `loopnz' +and `loopne' instructions only come in byte displacements, so that if +you use these instructions (`gcc' does not use them) you may get an +error message (and incorrect code). The AT&T 80386 assembler tries to +get around this problem by expanding `jcxz foo' to + + jcxz cx_zero + jmp cx_nonzero + cx_zero: jmp foo + cx_nonzero: + + +File: as.info, Node: i386-Float, Next: i386-SIMD, Prev: i386-Jumps, Up: i386-Dependent + +9.13.10 Floating Point +---------------------- + +All 80387 floating point types except packed BCD are supported. (BCD +support may be added without much difficulty). These data types are +16-, 32-, and 64- bit integers, and single (32-bit), double (64-bit), +and extended (80-bit) precision floating point. Each supported type +has an instruction mnemonic suffix and a constructor associated with +it. Instruction mnemonic suffixes specify the operand's data type. +Constructors build these data types into memory. + + * Floating point constructors are `.float' or `.single', `.double', + and `.tfloat' for 32-, 64-, and 80-bit formats. These correspond + to instruction mnemonic suffixes `s', `l', and `t'. `t' stands for + 80-bit (ten byte) real. The 80387 only supports this format via + the `fldt' (load 80-bit real to stack top) and `fstpt' (store + 80-bit real and pop stack) instructions. + + * Integer constructors are `.word', `.long' or `.int', and `.quad' + for the 16-, 32-, and 64-bit integer formats. The corresponding + instruction mnemonic suffixes are `s' (single), `l' (long), and + `q' (quad). As with the 80-bit real format, the 64-bit `q' format + is only present in the `fildq' (load quad integer to stack top) + and `fistpq' (store quad integer and pop stack) instructions. + + Register to register operations should not use instruction mnemonic +suffixes. `fstl %st, %st(1)' will give a warning, and be assembled as +if you wrote `fst %st, %st(1)', since all register to register +operations use 80-bit floating point operands. (Contrast this with +`fstl %st, mem', which converts `%st' from 80-bit to 64-bit floating +point format, then stores the result in the 4 byte location `mem') + + +File: as.info, Node: i386-SIMD, Next: i386-16bit, Prev: i386-Float, Up: i386-Dependent + +9.13.11 Intel's MMX and AMD's 3DNow! SIMD Operations +---------------------------------------------------- + +`as' supports Intel's MMX instruction set (SIMD instructions for +integer data), available on Intel's Pentium MMX processors and Pentium +II processors, AMD's K6 and K6-2 processors, Cyrix' M2 processor, and +probably others. It also supports AMD's 3DNow! instruction set (SIMD +instructions for 32-bit floating point data) available on AMD's K6-2 +processor and possibly others in the future. + + Currently, `as' does not support Intel's floating point SIMD, Katmai +(KNI). + + The eight 64-bit MMX operands, also used by 3DNow!, are called +`%mm0', `%mm1', ... `%mm7'. They contain eight 8-bit integers, four +16-bit integers, two 32-bit integers, one 64-bit integer, or two 32-bit +floating point values. The MMX registers cannot be used at the same +time as the floating point stack. + + See Intel and AMD documentation, keeping in mind that the operand +order in instructions is reversed from the Intel syntax. + + +File: as.info, Node: i386-16bit, Next: i386-Arch, Prev: i386-SIMD, Up: i386-Dependent + +9.13.12 Writing 16-bit Code +--------------------------- + +While `as' normally writes only "pure" 32-bit i386 code or 64-bit +x86-64 code depending on the default configuration, it also supports +writing code to run in real mode or in 16-bit protected mode code +segments. To do this, put a `.code16' or `.code16gcc' directive before +the assembly language instructions to be run in 16-bit mode. You can +switch `as' back to writing normal 32-bit code with the `.code32' +directive. + + `.code16gcc' provides experimental support for generating 16-bit +code from gcc, and differs from `.code16' in that `call', `ret', +`enter', `leave', `push', `pop', `pusha', `popa', `pushf', and `popf' +instructions default to 32-bit size. This is so that the stack pointer +is manipulated in the same way over function calls, allowing access to +function parameters at the same stack offsets as in 32-bit mode. +`.code16gcc' also automatically adds address size prefixes where +necessary to use the 32-bit addressing modes that gcc generates. + + The code which `as' generates in 16-bit mode will not necessarily +run on a 16-bit pre-80386 processor. To write code that runs on such a +processor, you must refrain from using _any_ 32-bit constructs which +require `as' to output address or operand size prefixes. + + Note that writing 16-bit code instructions by explicitly specifying a +prefix or an instruction mnemonic suffix within a 32-bit code section +generates different machine instructions than those generated for a +16-bit code segment. In a 32-bit code section, the following code +generates the machine opcode bytes `66 6a 04', which pushes the value +`4' onto the stack, decrementing `%esp' by 2. + + pushw $4 + + The same code in a 16-bit code section would generate the machine +opcode bytes `6a 04' (i.e., without the operand size prefix), which is +correct since the processor default operand size is assumed to be 16 +bits in a 16-bit code section. + + +File: as.info, Node: i386-Bugs, Next: i386-Notes, Prev: i386-Arch, Up: i386-Dependent + +9.13.13 AT&T Syntax bugs +------------------------ + +The UnixWare assembler, and probably other AT&T derived ix86 Unix +assemblers, generate floating point instructions with reversed source +and destination registers in certain cases. Unfortunately, gcc and +possibly many other programs use this reversed syntax, so we're stuck +with it. + + For example + + fsub %st,%st(3) + results in `%st(3)' being updated to `%st - %st(3)' rather than the +expected `%st(3) - %st'. This happens with all the non-commutative +arithmetic floating point operations with two register operands where +the source register is `%st' and the destination register is `%st(i)'. + + +File: as.info, Node: i386-Arch, Next: i386-Bugs, Prev: i386-16bit, Up: i386-Dependent + +9.13.14 Specifying CPU Architecture +----------------------------------- + +`as' may be told to assemble for a particular CPU (sub-)architecture +with the `.arch CPU_TYPE' directive. This directive enables a warning +when gas detects an instruction that is not supported on the CPU +specified. The choices for CPU_TYPE are: + +`i8086' `i186' `i286' `i386' +`i486' `i586' `i686' `pentium' +`pentiumpro' `pentiumii' `pentiumiii' `pentium4' +`prescott' `nocona' `core' `core2' +`corei7' `l1om' +`k6' `k6_2' `athlon' `k8' +`amdfam10' +`generic32' `generic64' +`.mmx' `.sse' `.sse2' `.sse3' +`.ssse3' `.sse4.1' `.sse4.2' `.sse4' +`.avx' `.vmx' `.smx' `.xsave' +`.aes' `.pclmul' `.fma' `.movbe' +`.ept' `.clflush' +`.3dnow' `.3dnowa' `.sse4a' `.sse5' +`.syscall' `.rdtscp' `.svme' `.abm' +`.padlock' + + Apart from the warning, there are only two other effects on `as' +operation; Firstly, if you specify a CPU other than `i486', then shift +by one instructions such as `sarl $1, %eax' will automatically use a +two byte opcode sequence. The larger three byte opcode sequence is +used on the 486 (and when no architecture is specified) because it +executes faster on the 486. Note that you can explicitly request the +two byte opcode by writing `sarl %eax'. Secondly, if you specify +`i8086', `i186', or `i286', _and_ `.code16' or `.code16gcc' then byte +offset conditional jumps will be promoted when necessary to a two +instruction sequence consisting of a conditional jump of the opposite +sense around an unconditional jump to the target. + + Following the CPU architecture (but not a sub-architecture, which +are those starting with a dot), you may specify `jumps' or `nojumps' to +control automatic promotion of conditional jumps. `jumps' is the +default, and enables jump promotion; All external jumps will be of the +long variety, and file-local jumps will be promoted as necessary. +(*note i386-Jumps::) `nojumps' leaves external conditional jumps as +byte offset jumps, and warns about file-local conditional jumps that +`as' promotes. Unconditional jumps are treated as for `jumps'. + + For example + + .arch i8086,nojumps + + +File: as.info, Node: i386-Notes, Prev: i386-Bugs, Up: i386-Dependent + +9.13.15 Notes +------------- + +There is some trickery concerning the `mul' and `imul' instructions +that deserves mention. The 16-, 32-, 64- and 128-bit expanding +multiplies (base opcode `0xf6'; extension 4 for `mul' and 5 for `imul') +can be output only in the one operand form. Thus, `imul %ebx, %eax' +does _not_ select the expanding multiply; the expanding multiply would +clobber the `%edx' register, and this would confuse `gcc' output. Use +`imul %ebx' to get the 64-bit product in `%edx:%eax'. + + We have added a two operand form of `imul' when the first operand is +an immediate mode expression and the second operand is a register. +This is just a shorthand, so that, multiplying `%eax' by 69, for +example, can be done with `imul $69, %eax' rather than `imul $69, %eax, +%eax'. + + +File: as.info, Node: i860-Dependent, Next: i960-Dependent, Prev: i386-Dependent, Up: Machine Dependencies + +9.14 Intel i860 Dependent Features +================================== + +* Menu: + +* Notes-i860:: i860 Notes +* Options-i860:: i860 Command-line Options +* Directives-i860:: i860 Machine Directives +* Opcodes for i860:: i860 Opcodes + + +File: as.info, Node: Notes-i860, Next: Options-i860, Up: i860-Dependent + +9.14.1 i860 Notes +----------------- + +This is a fairly complete i860 assembler which is compatible with the +UNIX System V/860 Release 4 assembler. However, it does not currently +support SVR4 PIC (i.e., `@GOT, @GOTOFF, @PLT'). + + Like the SVR4/860 assembler, the output object format is ELF32. +Currently, this is the only supported object format. If there is +sufficient interest, other formats such as COFF may be implemented. + + Both the Intel and AT&T/SVR4 syntaxes are supported, with the latter +being the default. One difference is that AT&T syntax requires the '%' +prefix on register names while Intel syntax does not. Another +difference is in the specification of relocatable expressions. The +Intel syntax is `ha%expression' whereas the SVR4 syntax is +`[expression]@ha' (and similarly for the "l" and "h" selectors). + + +File: as.info, Node: Options-i860, Next: Directives-i860, Prev: Notes-i860, Up: i860-Dependent + +9.14.2 i860 Command-line Options +-------------------------------- + +9.14.2.1 SVR4 compatibility options +................................... + +`-V' + Print assembler version. + +`-Qy' + Ignored. + +`-Qn' + Ignored. + +9.14.2.2 Other options +...................... + +`-EL' + Select little endian output (this is the default). + +`-EB' + Select big endian output. Note that the i860 always reads + instructions as little endian data, so this option only effects + data and not instructions. + +`-mwarn-expand' + Emit a warning message if any pseudo-instruction expansions + occurred. For example, a `or' instruction with an immediate + larger than 16-bits will be expanded into two instructions. This + is a very undesirable feature to rely on, so this flag can help + detect any code where it happens. One use of it, for instance, has + been to find and eliminate any place where `gcc' may emit these + pseudo-instructions. + +`-mxp' + Enable support for the i860XP instructions and control registers. + By default, this option is disabled so that only the base + instruction set (i.e., i860XR) is supported. + +`-mintel-syntax' + The i860 assembler defaults to AT&T/SVR4 syntax. This option + enables the Intel syntax. + + +File: as.info, Node: Directives-i860, Next: Opcodes for i860, Prev: Options-i860, Up: i860-Dependent + +9.14.3 i860 Machine Directives +------------------------------ + +`.dual' + Enter dual instruction mode. While this directive is supported, the + preferred way to use dual instruction mode is to explicitly code + the dual bit with the `d.' prefix. + +`.enddual' + Exit dual instruction mode. While this directive is supported, the + preferred way to use dual instruction mode is to explicitly code + the dual bit with the `d.' prefix. + +`.atmp' + Change the temporary register used when expanding pseudo + operations. The default register is `r31'. + + The `.dual', `.enddual', and `.atmp' directives are available only +in the Intel syntax mode. + + Both syntaxes allow for the standard `.align' directive. However, +the Intel syntax additionally allows keywords for the alignment +parameter: "`.align type'", where `type' is one of `.short', `.long', +`.quad', `.single', `.double' representing alignments of 2, 4, 16, 4, +and 8, respectively. + + +File: as.info, Node: Opcodes for i860, Prev: Directives-i860, Up: i860-Dependent + +9.14.4 i860 Opcodes +------------------- + +All of the Intel i860XR and i860XP machine instructions are supported. +Please see either _i860 Microprocessor Programmer's Reference Manual_ +or _i860 Microprocessor Architecture_ for more information. + +9.14.4.1 Other instruction support (pseudo-instructions) +........................................................ + +For compatibility with some other i860 assemblers, a number of +pseudo-instructions are supported. While these are supported, they are +a very undesirable feature that should be avoided - in particular, when +they result in an expansion to multiple actual i860 instructions. Below +are the pseudo-instructions that result in expansions. + * Load large immediate into general register: + + The pseudo-instruction `mov imm,%rn' (where the immediate does not + fit within a signed 16-bit field) will be expanded into: + orh large_imm@h,%r0,%rn + or large_imm@l,%rn,%rn + + * Load/store with relocatable address expression: + + For example, the pseudo-instruction `ld.b addr_exp(%rx),%rn' will + be expanded into: + orh addr_exp@ha,%rx,%r31 + ld.l addr_exp@l(%r31),%rn + + The analogous expansions apply to `ld.x, st.x, fld.x, pfld.x, + fst.x', and `pst.x' as well. + + * Signed large immediate with add/subtract: + + If any of the arithmetic operations `adds, addu, subs, subu' are + used with an immediate larger than 16-bits (signed), then they + will be expanded. For instance, the pseudo-instruction `adds + large_imm,%rx,%rn' expands to: + orh large_imm@h,%r0,%r31 + or large_imm@l,%r31,%r31 + adds %r31,%rx,%rn + + * Unsigned large immediate with logical operations: + + Logical operations (`or, andnot, or, xor') also result in + expansions. The pseudo-instruction `or large_imm,%rx,%rn' results + in: + orh large_imm@h,%rx,%r31 + or large_imm@l,%r31,%rn + + Similarly for the others, except for `and' which expands to: + andnot (-1 - large_imm)@h,%rx,%r31 + andnot (-1 - large_imm)@l,%r31,%rn + + +File: as.info, Node: i960-Dependent, Next: IA-64-Dependent, Prev: i860-Dependent, Up: Machine Dependencies + +9.15 Intel 80960 Dependent Features +=================================== + +* Menu: + +* Options-i960:: i960 Command-line Options +* Floating Point-i960:: Floating Point +* Directives-i960:: i960 Machine Directives +* Opcodes for i960:: i960 Opcodes + + +File: as.info, Node: Options-i960, Next: Floating Point-i960, Up: i960-Dependent + +9.15.1 i960 Command-line Options +-------------------------------- + +`-ACA | -ACA_A | -ACB | -ACC | -AKA | -AKB | -AKC | -AMC' + Select the 80960 architecture. Instructions or features not + supported by the selected architecture cause fatal errors. + + `-ACA' is equivalent to `-ACA_A'; `-AKC' is equivalent to `-AMC'. + Synonyms are provided for compatibility with other tools. + + If you do not specify any of these options, `as' generates code + for any instruction or feature that is supported by _some_ version + of the 960 (even if this means mixing architectures!). In + principle, `as' attempts to deduce the minimal sufficient + processor type if none is specified; depending on the object code + format, the processor type may be recorded in the object file. If + it is critical that the `as' output match a specific architecture, + specify that architecture explicitly. + +`-b' + Add code to collect information about conditional branches taken, + for later optimization using branch prediction bits. (The + conditional branch instructions have branch prediction bits in the + CA, CB, and CC architectures.) If BR represents a conditional + branch instruction, the following represents the code generated by + the assembler when `-b' is specified: + + call INCREMENT ROUTINE + .word 0 # pre-counter + Label: BR + call INCREMENT ROUTINE + .word 0 # post-counter + + The counter following a branch records the number of times that + branch was _not_ taken; the difference between the two counters is + the number of times the branch _was_ taken. + + A table of every such `Label' is also generated, so that the + external postprocessor `gbr960' (supplied by Intel) can locate all + the counters. This table is always labeled `__BRANCH_TABLE__'; + this is a local symbol to permit collecting statistics for many + separate object files. The table is word aligned, and begins with + a two-word header. The first word, initialized to 0, is used in + maintaining linked lists of branch tables. The second word is a + count of the number of entries in the table, which follow + immediately: each is a word, pointing to one of the labels + illustrated above. + + +------------+------------+------------+ ... +------------+ + | | | | | | + | *NEXT | COUNT: N | *BRLAB 1 | | *BRLAB N | + | | | | | | + +------------+------------+------------+ ... +------------+ + + __BRANCH_TABLE__ layout + + The first word of the header is used to locate multiple branch + tables, since each object file may contain one. Normally the links + are maintained with a call to an initialization routine, placed at + the beginning of each function in the file. The GNU C compiler + generates these calls automatically when you give it a `-b' option. + For further details, see the documentation of `gbr960'. + +`-no-relax' + Normally, Compare-and-Branch instructions with targets that require + displacements greater than 13 bits (or that have external targets) + are replaced with the corresponding compare (or `chkbit') and + branch instructions. You can use the `-no-relax' option to + specify that `as' should generate errors instead, if the target + displacement is larger than 13 bits. + + This option does not affect the Compare-and-Jump instructions; the + code emitted for them is _always_ adjusted when necessary + (depending on displacement size), regardless of whether you use + `-no-relax'. + + +File: as.info, Node: Floating Point-i960, Next: Directives-i960, Prev: Options-i960, Up: i960-Dependent + +9.15.2 Floating Point +--------------------- + +`as' generates IEEE floating-point numbers for the directives `.float', +`.double', `.extended', and `.single'. + + +File: as.info, Node: Directives-i960, Next: Opcodes for i960, Prev: Floating Point-i960, Up: i960-Dependent + +9.15.3 i960 Machine Directives +------------------------------ + +`.bss SYMBOL, LENGTH, ALIGN' + Reserve LENGTH bytes in the bss section for a local SYMBOL, + aligned to the power of two specified by ALIGN. LENGTH and ALIGN + must be positive absolute expressions. This directive differs + from `.lcomm' only in that it permits you to specify an alignment. + *Note `.lcomm': Lcomm. + +`.extended FLONUMS' + `.extended' expects zero or more flonums, separated by commas; for + each flonum, `.extended' emits an IEEE extended-format (80-bit) + floating-point number. + +`.leafproc CALL-LAB, BAL-LAB' + You can use the `.leafproc' directive in conjunction with the + optimized `callj' instruction to enable faster calls of leaf + procedures. If a procedure is known to call no other procedures, + you may define an entry point that skips procedure prolog code + (and that does not depend on system-supplied saved context), and + declare it as the BAL-LAB using `.leafproc'. If the procedure + also has an entry point that goes through the normal prolog, you + can specify that entry point as CALL-LAB. + + A `.leafproc' declaration is meant for use in conjunction with the + optimized call instruction `callj'; the directive records the data + needed later to choose between converting the `callj' into a `bal' + or a `call'. + + CALL-LAB is optional; if only one argument is present, or if the + two arguments are identical, the single argument is assumed to be + the `bal' entry point. + +`.sysproc NAME, INDEX' + The `.sysproc' directive defines a name for a system procedure. + After you define it using `.sysproc', you can use NAME to refer to + the system procedure identified by INDEX when calling procedures + with the optimized call instruction `callj'. + + Both arguments are required; INDEX must be between 0 and 31 + (inclusive). + + +File: as.info, Node: Opcodes for i960, Prev: Directives-i960, Up: i960-Dependent + +9.15.4 i960 Opcodes +------------------- + +All Intel 960 machine instructions are supported; *note i960 +Command-line Options: Options-i960. for a discussion of selecting the +instruction subset for a particular 960 architecture. + + Some opcodes are processed beyond simply emitting a single +corresponding instruction: `callj', and Compare-and-Branch or +Compare-and-Jump instructions with target displacements larger than 13 +bits. + +* Menu: + +* callj-i960:: `callj' +* Compare-and-branch-i960:: Compare-and-Branch + + +File: as.info, Node: callj-i960, Next: Compare-and-branch-i960, Up: Opcodes for i960 + +9.15.4.1 `callj' +................ + +You can write `callj' to have the assembler or the linker determine the +most appropriate form of subroutine call: `call', `bal', or `calls'. +If the assembly source contains enough information--a `.leafproc' or +`.sysproc' directive defining the operand--then `as' translates the +`callj'; if not, it simply emits the `callj', leaving it for the linker +to resolve. + + +File: as.info, Node: Compare-and-branch-i960, Prev: callj-i960, Up: Opcodes for i960 + +9.15.4.2 Compare-and-Branch +........................... + +The 960 architectures provide combined Compare-and-Branch instructions +that permit you to store the branch target in the lower 13 bits of the +instruction word itself. However, if you specify a branch target far +enough away that its address won't fit in 13 bits, the assembler can +either issue an error, or convert your Compare-and-Branch instruction +into separate instructions to do the compare and the branch. + + Whether `as' gives an error or expands the instruction depends on +two choices you can make: whether you use the `-no-relax' option, and +whether you use a "Compare and Branch" instruction or a "Compare and +Jump" instruction. The "Jump" instructions are _always_ expanded if +necessary; the "Branch" instructions are expanded when necessary +_unless_ you specify `-no-relax'--in which case `as' gives an error +instead. + + These are the Compare-and-Branch instructions, their "Jump" variants, +and the instruction pairs they may expand into: + + Compare and + Branch Jump Expanded to + ------ ------ ------------ + bbc chkbit; bno + bbs chkbit; bo + cmpibe cmpije cmpi; be + cmpibg cmpijg cmpi; bg + cmpibge cmpijge cmpi; bge + cmpibl cmpijl cmpi; bl + cmpible cmpijle cmpi; ble + cmpibno cmpijno cmpi; bno + cmpibne cmpijne cmpi; bne + cmpibo cmpijo cmpi; bo + cmpobe cmpoje cmpo; be + cmpobg cmpojg cmpo; bg + cmpobge cmpojge cmpo; bge + cmpobl cmpojl cmpo; bl + cmpoble cmpojle cmpo; ble + cmpobne cmpojne cmpo; bne + + +File: as.info, Node: IA-64-Dependent, Next: IP2K-Dependent, Prev: i960-Dependent, Up: Machine Dependencies + +9.16 IA-64 Dependent Features +============================= + +* Menu: + +* IA-64 Options:: Options +* IA-64 Syntax:: Syntax +* IA-64 Opcodes:: Opcodes + + +File: as.info, Node: IA-64 Options, Next: IA-64 Syntax, Up: IA-64-Dependent + +9.16.1 Options +-------------- + +`-mconstant-gp' + This option instructs the assembler to mark the resulting object + file as using the "constant GP" model. With this model, it is + assumed that the entire program uses a single global pointer (GP) + value. Note that this option does not in any fashion affect the + machine code emitted by the assembler. All it does is turn on the + EF_IA_64_CONS_GP flag in the ELF file header. + +`-mauto-pic' + This option instructs the assembler to mark the resulting object + file as using the "constant GP without function descriptor" data + model. This model is like the "constant GP" model, except that it + additionally does away with function descriptors. What this means + is that the address of a function refers directly to the + function's code entry-point. Normally, such an address would + refer to a function descriptor, which contains both the code + entry-point and the GP-value needed by the function. Note that + this option does not in any fashion affect the machine code + emitted by the assembler. All it does is turn on the + EF_IA_64_NOFUNCDESC_CONS_GP flag in the ELF file header. + +`-milp32' + +`-milp64' + +`-mlp64' + +`-mp64' + These options select the data model. The assembler defaults to + `-mlp64' (LP64 data model). + +`-mle' + +`-mbe' + These options select the byte order. The `-mle' option selects + little-endian byte order (default) and `-mbe' selects big-endian + byte order. Note that IA-64 machine code always uses + little-endian byte order. + +`-mtune=itanium1' + +`-mtune=itanium2' + Tune for a particular IA-64 CPU, ITANIUM1 or ITANIUM2. The default + is ITANIUM2. + +`-munwind-check=warning' + +`-munwind-check=error' + These options control what the assembler will do when performing + consistency checks on unwind directives. `-munwind-check=warning' + will make the assembler issue a warning when an unwind directive + check fails. This is the default. `-munwind-check=error' will + make the assembler issue an error when an unwind directive check + fails. + +`-mhint.b=ok' + +`-mhint.b=warning' + +`-mhint.b=error' + These options control what the assembler will do when the `hint.b' + instruction is used. `-mhint.b=ok' will make the assembler accept + `hint.b'. `-mint.b=warning' will make the assembler issue a + warning when `hint.b' is used. `-mhint.b=error' will make the + assembler treat `hint.b' as an error, which is the default. + +`-x' + +`-xexplicit' + These options turn on dependency violation checking. + +`-xauto' + This option instructs the assembler to automatically insert stop + bits where necessary to remove dependency violations. This is the + default mode. + +`-xnone' + This option turns off dependency violation checking. + +`-xdebug' + This turns on debug output intended to help tracking down bugs in + the dependency violation checker. + +`-xdebugn' + This is a shortcut for -xnone -xdebug. + +`-xdebugx' + This is a shortcut for -xexplicit -xdebug. + + + +File: as.info, Node: IA-64 Syntax, Next: IA-64 Opcodes, Prev: IA-64 Options, Up: IA-64-Dependent + +9.16.2 Syntax +------------- + +The assembler syntax closely follows the IA-64 Assembly Language +Reference Guide. + +* Menu: + +* IA-64-Chars:: Special Characters +* IA-64-Regs:: Register Names +* IA-64-Bits:: Bit Names + + +File: as.info, Node: IA-64-Chars, Next: IA-64-Regs, Up: IA-64 Syntax + +9.16.2.1 Special Characters +........................... + +`//' is the line comment token. + + `;' can be used instead of a newline to separate statements. + + +File: as.info, Node: IA-64-Regs, Next: IA-64-Bits, Prev: IA-64-Chars, Up: IA-64 Syntax + +9.16.2.2 Register Names +....................... + +The 128 integer registers are referred to as `rN'. The 128 +floating-point registers are referred to as `fN'. The 128 application +registers are referred to as `arN'. The 128 control registers are +referred to as `crN'. The 64 one-bit predicate registers are referred +to as `pN'. The 8 branch registers are referred to as `bN'. In +addition, the assembler defines a number of aliases: `gp' (`r1'), `sp' +(`r12'), `rp' (`b0'), `ret0' (`r8'), `ret1' (`r9'), `ret2' (`r10'), +`ret3' (`r9'), `fargN' (`f8+N'), and `fretN' (`f8+N'). + + For convenience, the assembler also defines aliases for all named +application and control registers. For example, `ar.bsp' refers to the +register backing store pointer (`ar17'). Similarly, `cr.eoi' refers to +the end-of-interrupt register (`cr67'). + + +File: as.info, Node: IA-64-Bits, Prev: IA-64-Regs, Up: IA-64 Syntax + +9.16.2.3 IA-64 Processor-Status-Register (PSR) Bit Names +........................................................ + +The assembler defines bit masks for each of the bits in the IA-64 +processor status register. For example, `psr.ic' corresponds to a +value of 0x2000. These masks are primarily intended for use with the +`ssm'/`sum' and `rsm'/`rum' instructions, but they can be used anywhere +else where an integer constant is expected. + + +File: as.info, Node: IA-64 Opcodes, Prev: IA-64 Syntax, Up: IA-64-Dependent + +9.16.3 Opcodes +-------------- + +For detailed information on the IA-64 machine instruction set, see the +IA-64 Architecture Handbook +(http://developer.intel.com/design/itanium/arch_spec.htm). + + +File: as.info, Node: IP2K-Dependent, Next: LM32-Dependent, Prev: IA-64-Dependent, Up: Machine Dependencies + +9.17 IP2K Dependent Features +============================ + +* Menu: + +* IP2K-Opts:: IP2K Options + + +File: as.info, Node: IP2K-Opts, Up: IP2K-Dependent + +9.17.1 IP2K Options +------------------- + +The Ubicom IP2K version of `as' has a few machine dependent options: + +`-mip2022ext' + `as' can assemble the extended IP2022 instructions, but it will + only do so if this is specifically allowed via this command line + option. + +`-mip2022' + This option restores the assembler's default behaviour of not + permitting the extended IP2022 instructions to be assembled. + + + +File: as.info, Node: LM32-Dependent, Next: M32C-Dependent, Prev: IP2K-Dependent, Up: Machine Dependencies + +9.18 LM32 Dependent Features +============================ + +* Menu: + +* LM32 Options:: Options +* LM32 Syntax:: Syntax +* LM32 Opcodes:: Opcodes + + +File: as.info, Node: LM32 Options, Next: LM32 Syntax, Up: LM32-Dependent + +9.18.1 Options +-------------- + +`-mmultiply-enabled' + Enable multiply instructions. + +`-mdivide-enabled' + Enable divide instructions. + +`-mbarrel-shift-enabled' + Enable barrel-shift instructions. + +`-msign-extend-enabled' + Enable sign extend instructions. + +`-muser-enabled' + Enable user defined instructions. + +`-micache-enabled' + Enable instruction cache related CSRs. + +`-mdcache-enabled' + Enable data cache related CSRs. + +`-mbreak-enabled' + Enable break instructions. + +`-mall-enabled' + Enable all instructions and CSRs. + + + +File: as.info, Node: LM32 Syntax, Next: LM32 Opcodes, Prev: LM32 Options, Up: LM32-Dependent + +9.18.2 Syntax +------------- + +* Menu: + +* LM32-Regs:: Register Names +* LM32-Modifiers:: Relocatable Expression Modifiers + + +File: as.info, Node: LM32-Regs, Next: LM32-Modifiers, Up: LM32 Syntax + +9.18.2.1 Register Names +....................... + +LM32 has 32 x 32-bit general purpose registers `r0', `r1', ... `r31'. + + The following aliases are defined: `gp' - `r26', `fp' - `r27', `sp' +- `r28', `ra' - `r29', `ea' - `r30', `ba' - `r31'. + + LM32 has the following Control and Status Registers (CSRs). + +`IE' + Interrupt enable. + +`IM' + Interrupt mask. + +`IP' + Interrupt pending. + +`ICC' + Instruction cache control. + +`DCC' + Data cache control. + +`CC' + Cycle counter. + +`CFG' + Configuration. + +`EBA' + Exception base address. + +`DC' + Debug control. + +`DEBA' + Debug exception base address. + +`JTX' + JTAG transmit. + +`JRX' + JTAG receive. + +`BP0' + Breakpoint 0. + +`BP1' + Breakpoint 1. + +`BP2' + Breakpoint 2. + +`BP3' + Breakpoint 3. + +`WP0' + Watchpoint 0. + +`WP1' + Watchpoint 1. + +`WP2' + Watchpoint 2. + +`WP3' + Watchpoint 3. + + +File: as.info, Node: LM32-Modifiers, Prev: LM32-Regs, Up: LM32 Syntax + +9.18.2.2 Relocatable Expression Modifiers +......................................... + +The assembler supports several modifiers when using relocatable +addresses in LM32 instruction operands. The general syntax is the +following: + + modifier(relocatable-expression) + +`lo' + This modifier allows you to use bits 0 through 15 of an address + expression as 16 bit relocatable expression. + +`hi' + This modifier allows you to use bits 16 through 23 of an address + expression as 16 bit relocatable expression. + + For example + + ori r4, r4, lo(sym+10) + orhi r4, r4, hi(sym+10) + +`gp' + This modified creates a 16-bit relocatable expression that is the + offset of the symbol from the global pointer. + + mva r4, gp(sym) + +`got' + This modifier places a symbol in the GOT and creates a 16-bit + relocatable expression that is the offset into the GOT of this + symbol. + + lw r4, (gp+got(sym)) + +`gotofflo16' + This modifier allows you to use the bits 0 through 15 of an + address which is an offset from the GOT. + +`gotoffhi16' + This modifier allows you to use the bits 16 through 31 of an + address which is an offset from the GOT. + + orhi r4, r4, gotoffhi16(lsym) + addi r4, r4, gotofflo16(lsym) + + + +File: as.info, Node: LM32 Opcodes, Prev: LM32 Syntax, Up: LM32-Dependent + +9.18.3 Opcodes +-------------- + +For detailed information on the LM32 machine instruction set, see +`http://www.latticesemi.com/products/intellectualproperty/ipcores/mico32/'. + + `as' implements all the standard LM32 opcodes. + + +File: as.info, Node: M32C-Dependent, Next: M32R-Dependent, Prev: LM32-Dependent, Up: Machine Dependencies + +9.19 M32C Dependent Features +============================ + + `as' can assemble code for several different members of the Renesas +M32C family. Normally the default is to assemble code for the M16C +microprocessor. The `-m32c' option may be used to change the default +to the M32C microprocessor. + +* Menu: + +* M32C-Opts:: M32C Options +* M32C-Modifiers:: Symbolic Operand Modifiers + + +File: as.info, Node: M32C-Opts, Next: M32C-Modifiers, Up: M32C-Dependent + +9.19.1 M32C Options +------------------- + +The Renesas M32C version of `as' has these machine-dependent options: + +`-m32c' + Assemble M32C instructions. + +`-m16c' + Assemble M16C instructions (default). + +`-relax' + Enable support for link-time relaxations. + +`-h-tick-hex' + Support H'00 style hex constants in addition to 0x00 style. + + + +File: as.info, Node: M32C-Modifiers, Prev: M32C-Opts, Up: M32C-Dependent + +9.19.2 Symbolic Operand Modifiers +--------------------------------- + +The assembler supports several modifiers when using symbol addresses in +M32C instruction operands. The general syntax is the following: + + %modifier(symbol) + +`%dsp8' +`%dsp16' + These modifiers override the assembler's assumptions about how big + a symbol's address is. Normally, when it sees an operand like + `sym[a0]' it assumes `sym' may require the widest displacement + field (16 bits for `-m16c', 24 bits for `-m32c'). These modifiers + tell it to assume the address will fit in an 8 or 16 bit + (respectively) unsigned displacement. Note that, of course, if it + doesn't actually fit you will get linker errors. Example: + + mov.w %dsp8(sym)[a0],r1 + mov.b #0,%dsp8(sym)[a0] + +`%hi8' + This modifier allows you to load bits 16 through 23 of a 24 bit + address into an 8 bit register. This is useful with, for example, + the M16C `smovf' instruction, which expects a 20 bit address in + `r1h' and `a0'. Example: + + mov.b #%hi8(sym),r1h + mov.w #%lo16(sym),a0 + smovf.b + +`%lo16' + Likewise, this modifier allows you to load bits 0 through 15 of a + 24 bit address into a 16 bit register. + +`%hi16' + This modifier allows you to load bits 16 through 31 of a 32 bit + address into a 16 bit register. While the M32C family only has 24 + bits of address space, it does support addresses in pairs of 16 bit + registers (like `a1a0' for the `lde' instruction). This modifier + is for loading the upper half in such cases. Example: + + mov.w #%hi16(sym),a1 + mov.w #%lo16(sym),a0 + ... + lde.w [a1a0],r1 + + + +File: as.info, Node: M32R-Dependent, Next: M68K-Dependent, Prev: M32C-Dependent, Up: Machine Dependencies + +9.20 M32R Dependent Features +============================ + +* Menu: + +* M32R-Opts:: M32R Options +* M32R-Directives:: M32R Directives +* M32R-Warnings:: M32R Warnings + + +File: as.info, Node: M32R-Opts, Next: M32R-Directives, Up: M32R-Dependent + +9.20.1 M32R Options +------------------- + +The Renease M32R version of `as' has a few machine dependent options: + +`-m32rx' + `as' can assemble code for several different members of the + Renesas M32R family. Normally the default is to assemble code for + the M32R microprocessor. This option may be used to change the + default to the M32RX microprocessor, which adds some more + instructions to the basic M32R instruction set, and some + additional parameters to some of the original instructions. + +`-m32r2' + This option changes the target processor to the the M32R2 + microprocessor. + +`-m32r' + This option can be used to restore the assembler's default + behaviour of assembling for the M32R microprocessor. This can be + useful if the default has been changed by a previous command line + option. + +`-little' + This option tells the assembler to produce little-endian code and + data. The default is dependent upon how the toolchain was + configured. + +`-EL' + This is a synonym for _-little_. + +`-big' + This option tells the assembler to produce big-endian code and + data. + +`-EB' + This is a synonum for _-big_. + +`-KPIC' + This option specifies that the output of the assembler should be + marked as position-independent code (PIC). + +`-parallel' + This option tells the assembler to attempts to combine two + sequential instructions into a single, parallel instruction, where + it is legal to do so. + +`-no-parallel' + This option disables a previously enabled _-parallel_ option. + +`-no-bitinst' + This option disables the support for the extended bit-field + instructions provided by the M32R2. If this support needs to be + re-enabled the _-bitinst_ switch can be used to restore it. + +`-O' + This option tells the assembler to attempt to optimize the + instructions that it produces. This includes filling delay slots + and converting sequential instructions into parallel ones. This + option implies _-parallel_. + +`-warn-explicit-parallel-conflicts' + Instructs `as' to produce warning messages when questionable + parallel instructions are encountered. This option is enabled by + default, but `gcc' disables it when it invokes `as' directly. + Questionable instructions are those whose behaviour would be + different if they were executed sequentially. For example the + code fragment `mv r1, r2 || mv r3, r1' produces a different result + from `mv r1, r2 \n mv r3, r1' since the former moves r1 into r3 + and then r2 into r1, whereas the later moves r2 into r1 and r3. + +`-Wp' + This is a shorter synonym for the + _-warn-explicit-parallel-conflicts_ option. + +`-no-warn-explicit-parallel-conflicts' + Instructs `as' not to produce warning messages when questionable + parallel instructions are encountered. + +`-Wnp' + This is a shorter synonym for the + _-no-warn-explicit-parallel-conflicts_ option. + +`-ignore-parallel-conflicts' + This option tells the assembler's to stop checking parallel + instructions for constraint violations. This ability is provided + for hardware vendors testing chip designs and should not be used + under normal circumstances. + +`-no-ignore-parallel-conflicts' + This option restores the assembler's default behaviour of checking + parallel instructions to detect constraint violations. + +`-Ip' + This is a shorter synonym for the _-ignore-parallel-conflicts_ + option. + +`-nIp' + This is a shorter synonym for the _-no-ignore-parallel-conflicts_ + option. + +`-warn-unmatched-high' + This option tells the assembler to produce a warning message if a + `.high' pseudo op is encountered without a matching `.low' pseudo + op. The presence of such an unmatched pseudo op usually indicates + a programming error. + +`-no-warn-unmatched-high' + Disables a previously enabled _-warn-unmatched-high_ option. + +`-Wuh' + This is a shorter synonym for the _-warn-unmatched-high_ option. + +`-Wnuh' + This is a shorter synonym for the _-no-warn-unmatched-high_ option. + + + +File: as.info, Node: M32R-Directives, Next: M32R-Warnings, Prev: M32R-Opts, Up: M32R-Dependent + +9.20.2 M32R Directives +---------------------- + +The Renease M32R version of `as' has a few architecture specific +directives: + +`low EXPRESSION' + The `low' directive computes the value of its expression and + places the lower 16-bits of the result into the immediate-field of + the instruction. For example: + + or3 r0, r0, #low(0x12345678) ; compute r0 = r0 | 0x5678 + add3, r0, r0, #low(fred) ; compute r0 = r0 + low 16-bits of address of fred + +`high EXPRESSION' + The `high' directive computes the value of its expression and + places the upper 16-bits of the result into the immediate-field of + the instruction. For example: + + seth r0, #high(0x12345678) ; compute r0 = 0x12340000 + seth, r0, #high(fred) ; compute r0 = upper 16-bits of address of fred + +`shigh EXPRESSION' + The `shigh' directive is very similar to the `high' directive. It + also computes the value of its expression and places the upper + 16-bits of the result into the immediate-field of the instruction. + The difference is that `shigh' also checks to see if the lower + 16-bits could be interpreted as a signed number, and if so it + assumes that a borrow will occur from the upper-16 bits. To + compensate for this the `shigh' directive pre-biases the upper 16 + bit value by adding one to it. For example: + + For example: + + seth r0, #shigh(0x12345678) ; compute r0 = 0x12340000 + seth r0, #shigh(0x00008000) ; compute r0 = 0x00010000 + + In the second example the lower 16-bits are 0x8000. If these are + treated as a signed value and sign extended to 32-bits then the + value becomes 0xffff8000. If this value is then added to + 0x00010000 then the result is 0x00008000. + + This behaviour is to allow for the different semantics of the + `or3' and `add3' instructions. The `or3' instruction treats its + 16-bit immediate argument as unsigned whereas the `add3' treats + its 16-bit immediate as a signed value. So for example: + + seth r0, #shigh(0x00008000) + add3 r0, r0, #low(0x00008000) + + Produces the correct result in r0, whereas: + + seth r0, #shigh(0x00008000) + or3 r0, r0, #low(0x00008000) + + Stores 0xffff8000 into r0. + + Note - the `shigh' directive does not know where in the assembly + source code the lower 16-bits of the value are going set, so it + cannot check to make sure that an `or3' instruction is being used + rather than an `add3' instruction. It is up to the programmer to + make sure that correct directives are used. + +`.m32r' + The directive performs a similar thing as the _-m32r_ command line + option. It tells the assembler to only accept M32R instructions + from now on. An instructions from later M32R architectures are + refused. + +`.m32rx' + The directive performs a similar thing as the _-m32rx_ command + line option. It tells the assembler to start accepting the extra + instructions in the M32RX ISA as well as the ordinary M32R ISA. + +`.m32r2' + The directive performs a similar thing as the _-m32r2_ command + line option. It tells the assembler to start accepting the extra + instructions in the M32R2 ISA as well as the ordinary M32R ISA. + +`.little' + The directive performs a similar thing as the _-little_ command + line option. It tells the assembler to start producing + little-endian code and data. This option should be used with care + as producing mixed-endian binary files is fraught with danger. + +`.big' + The directive performs a similar thing as the _-big_ command line + option. It tells the assembler to start producing big-endian code + and data. This option should be used with care as producing + mixed-endian binary files is fraught with danger. + + + +File: as.info, Node: M32R-Warnings, Prev: M32R-Directives, Up: M32R-Dependent + +9.20.3 M32R Warnings +-------------------- + +There are several warning and error messages that can be produced by +`as' which are specific to the M32R: + +`output of 1st instruction is the same as an input to 2nd instruction - is this intentional ?' + This message is only produced if warnings for explicit parallel + conflicts have been enabled. It indicates that the assembler has + encountered a parallel instruction in which the destination + register of the left hand instruction is used as an input register + in the right hand instruction. For example in this code fragment + `mv r1, r2 || neg r3, r1' register r1 is the destination of the + move instruction and the input to the neg instruction. + +`output of 2nd instruction is the same as an input to 1st instruction - is this intentional ?' + This message is only produced if warnings for explicit parallel + conflicts have been enabled. It indicates that the assembler has + encountered a parallel instruction in which the destination + register of the right hand instruction is used as an input + register in the left hand instruction. For example in this code + fragment `mv r1, r2 || neg r2, r3' register r2 is the destination + of the neg instruction and the input to the move instruction. + +`instruction `...' is for the M32RX only' + This message is produced when the assembler encounters an + instruction which is only supported by the M32Rx processor, and + the `-m32rx' command line flag has not been specified to allow + assembly of such instructions. + +`unknown instruction `...'' + This message is produced when the assembler encounters an + instruction which it does not recognize. + +`only the NOP instruction can be issued in parallel on the m32r' + This message is produced when the assembler encounters a parallel + instruction which does not involve a NOP instruction and the + `-m32rx' command line flag has not been specified. Only the M32Rx + processor is able to execute two instructions in parallel. + +`instruction `...' cannot be executed in parallel.' + This message is produced when the assembler encounters a parallel + instruction which is made up of one or two instructions which + cannot be executed in parallel. + +`Instructions share the same execution pipeline' + This message is produced when the assembler encounters a parallel + instruction whoes components both use the same execution pipeline. + +`Instructions write to the same destination register.' + This message is produced when the assembler encounters a parallel + instruction where both components attempt to modify the same + register. For example these code fragments will produce this + message: `mv r1, r2 || neg r1, r3' `jl r0 || mv r14, r1' `st r2, + @-r1 || mv r1, r3' `mv r1, r2 || ld r0, @r1+' `cmp r1, r2 || addx + r3, r4' (Both write to the condition bit) + + + +File: as.info, Node: M68K-Dependent, Next: M68HC11-Dependent, Prev: M32R-Dependent, Up: Machine Dependencies + +9.21 M680x0 Dependent Features +============================== + +* Menu: + +* M68K-Opts:: M680x0 Options +* M68K-Syntax:: Syntax +* M68K-Moto-Syntax:: Motorola Syntax +* M68K-Float:: Floating Point +* M68K-Directives:: 680x0 Machine Directives +* M68K-opcodes:: Opcodes + + +File: as.info, Node: M68K-Opts, Next: M68K-Syntax, Up: M68K-Dependent + +9.21.1 M680x0 Options +--------------------- + +The Motorola 680x0 version of `as' has a few machine dependent options: + +`-march=ARCHITECTURE' + This option specifies a target architecture. The following + architectures are recognized: `68000', `68010', `68020', `68030', + `68040', `68060', `cpu32', `isaa', `isaaplus', `isab', `isac' and + `cfv4e'. + +`-mcpu=CPU' + This option specifies a target cpu. When used in conjunction with + the `-march' option, the cpu must be within the specified + architecture. Also, the generic features of the architecture are + used for instruction generation, rather than those of the specific + chip. + +`-m[no-]68851' + +`-m[no-]68881' + +`-m[no-]div' + +`-m[no-]usp' + +`-m[no-]float' + +`-m[no-]mac' + +`-m[no-]emac' + Enable or disable various architecture specific features. If a + chip or architecture by default supports an option (for instance + `-march=isaaplus' includes the `-mdiv' option), explicitly + disabling the option will override the default. + +`-l' + You can use the `-l' option to shorten the size of references to + undefined symbols. If you do not use the `-l' option, references + to undefined symbols are wide enough for a full `long' (32 bits). + (Since `as' cannot know where these symbols end up, `as' can only + allocate space for the linker to fill in later. Since `as' does + not know how far away these symbols are, it allocates as much + space as it can.) If you use this option, the references are only + one word wide (16 bits). This may be useful if you want the + object file to be as small as possible, and you know that the + relevant symbols are always less than 17 bits away. + +`--register-prefix-optional' + For some configurations, especially those where the compiler + normally does not prepend an underscore to the names of user + variables, the assembler requires a `%' before any use of a + register name. This is intended to let the assembler distinguish + between C variables and functions named `a0' through `a7', and so + on. The `%' is always accepted, but is not required for certain + configurations, notably `sun3'. The `--register-prefix-optional' + option may be used to permit omitting the `%' even for + configurations for which it is normally required. If this is + done, it will generally be impossible to refer to C variables and + functions with the same names as register names. + +`--bitwise-or' + Normally the character `|' is treated as a comment character, which + means that it can not be used in expressions. The `--bitwise-or' + option turns `|' into a normal character. In this mode, you must + either use C style comments, or start comments with a `#' character + at the beginning of a line. + +`--base-size-default-16 --base-size-default-32' + If you use an addressing mode with a base register without + specifying the size, `as' will normally use the full 32 bit value. + For example, the addressing mode `%a0@(%d0)' is equivalent to + `%a0@(%d0:l)'. You may use the `--base-size-default-16' option to + tell `as' to default to using the 16 bit value. In this case, + `%a0@(%d0)' is equivalent to `%a0@(%d0:w)'. You may use the + `--base-size-default-32' option to restore the default behaviour. + +`--disp-size-default-16 --disp-size-default-32' + If you use an addressing mode with a displacement, and the value + of the displacement is not known, `as' will normally assume that + the value is 32 bits. For example, if the symbol `disp' has not + been defined, `as' will assemble the addressing mode + `%a0@(disp,%d0)' as though `disp' is a 32 bit value. You may use + the `--disp-size-default-16' option to tell `as' to instead assume + that the displacement is 16 bits. In this case, `as' will + assemble `%a0@(disp,%d0)' as though `disp' is a 16 bit value. You + may use the `--disp-size-default-32' option to restore the default + behaviour. + +`--pcrel' + Always keep branches PC-relative. In the M680x0 architecture all + branches are defined as PC-relative. However, on some processors + they are limited to word displacements maximum. When `as' needs a + long branch that is not available, it normally emits an absolute + jump instead. This option disables this substitution. When this + option is given and no long branches are available, only word + branches will be emitted. An error message will be generated if a + word branch cannot reach its target. This option has no effect on + 68020 and other processors that have long branches. *note Branch + Improvement: M68K-Branch. + +`-m68000' + `as' can assemble code for several different members of the + Motorola 680x0 family. The default depends upon how `as' was + configured when it was built; normally, the default is to assemble + code for the 68020 microprocessor. The following options may be + used to change the default. These options control which + instructions and addressing modes are permitted. The members of + the 680x0 family are very similar. For detailed information about + the differences, see the Motorola manuals. + + `-m68000' + `-m68ec000' + `-m68hc000' + `-m68hc001' + `-m68008' + `-m68302' + `-m68306' + `-m68307' + `-m68322' + `-m68356' + Assemble for the 68000. `-m68008', `-m68302', and so on are + synonyms for `-m68000', since the chips are the same from the + point of view of the assembler. + + `-m68010' + Assemble for the 68010. + + `-m68020' + `-m68ec020' + Assemble for the 68020. This is normally the default. + + `-m68030' + `-m68ec030' + Assemble for the 68030. + + `-m68040' + `-m68ec040' + Assemble for the 68040. + + `-m68060' + `-m68ec060' + Assemble for the 68060. + + `-mcpu32' + `-m68330' + `-m68331' + `-m68332' + `-m68333' + `-m68334' + `-m68336' + `-m68340' + `-m68341' + `-m68349' + `-m68360' + Assemble for the CPU32 family of chips. + + `-m5200' + + `-m5202' + + `-m5204' + + `-m5206' + + `-m5206e' + + `-m521x' + + `-m5249' + + `-m528x' + + `-m5307' + + `-m5407' + + `-m547x' + + `-m548x' + + `-mcfv4' + + `-mcfv4e' + Assemble for the ColdFire family of chips. + + `-m68881' + `-m68882' + Assemble 68881 floating point instructions. This is the + default for the 68020, 68030, and the CPU32. The 68040 and + 68060 always support floating point instructions. + + `-mno-68881' + Do not assemble 68881 floating point instructions. This is + the default for 68000 and the 68010. The 68040 and 68060 + always support floating point instructions, even if this + option is used. + + `-m68851' + Assemble 68851 MMU instructions. This is the default for the + 68020, 68030, and 68060. The 68040 accepts a somewhat + different set of MMU instructions; `-m68851' and `-m68040' + should not be used together. + + `-mno-68851' + Do not assemble 68851 MMU instructions. This is the default + for the 68000, 68010, and the CPU32. The 68040 accepts a + somewhat different set of MMU instructions. + + +File: as.info, Node: M68K-Syntax, Next: M68K-Moto-Syntax, Prev: M68K-Opts, Up: M68K-Dependent + +9.21.2 Syntax +------------- + +This syntax for the Motorola 680x0 was developed at MIT. + + The 680x0 version of `as' uses instructions names and syntax +compatible with the Sun assembler. Intervening periods are ignored; +for example, `movl' is equivalent to `mov.l'. + + In the following table APC stands for any of the address registers +(`%a0' through `%a7'), the program counter (`%pc'), the zero-address +relative to the program counter (`%zpc'), a suppressed address register +(`%za0' through `%za7'), or it may be omitted entirely. The use of +SIZE means one of `w' or `l', and it may be omitted, along with the +leading colon, unless a scale is also specified. The use of SCALE +means one of `1', `2', `4', or `8', and it may always be omitted along +with the leading colon. + + The following addressing modes are understood: +"Immediate" + `#NUMBER' + +"Data Register" + `%d0' through `%d7' + +"Address Register" + `%a0' through `%a7' + `%a7' is also known as `%sp', i.e., the Stack Pointer. `%a6' is + also known as `%fp', the Frame Pointer. + +"Address Register Indirect" + `%a0@' through `%a7@' + +"Address Register Postincrement" + `%a0@+' through `%a7@+' + +"Address Register Predecrement" + `%a0@-' through `%a7@-' + +"Indirect Plus Offset" + `APC@(NUMBER)' + +"Index" + `APC@(NUMBER,REGISTER:SIZE:SCALE)' + + The NUMBER may be omitted. + +"Postindex" + `APC@(NUMBER)@(ONUMBER,REGISTER:SIZE:SCALE)' + + The ONUMBER or the REGISTER, but not both, may be omitted. + +"Preindex" + `APC@(NUMBER,REGISTER:SIZE:SCALE)@(ONUMBER)' + + The NUMBER may be omitted. Omitting the REGISTER produces the + Postindex addressing mode. + +"Absolute" + `SYMBOL', or `DIGITS', optionally followed by `:b', `:w', or `:l'. + + +File: as.info, Node: M68K-Moto-Syntax, Next: M68K-Float, Prev: M68K-Syntax, Up: M68K-Dependent + +9.21.3 Motorola Syntax +---------------------- + +The standard Motorola syntax for this chip differs from the syntax +already discussed (*note Syntax: M68K-Syntax.). `as' can accept +Motorola syntax for operands, even if MIT syntax is used for other +operands in the same instruction. The two kinds of syntax are fully +compatible. + + In the following table APC stands for any of the address registers +(`%a0' through `%a7'), the program counter (`%pc'), the zero-address +relative to the program counter (`%zpc'), or a suppressed address +register (`%za0' through `%za7'). The use of SIZE means one of `w' or +`l', and it may always be omitted along with the leading dot. The use +of SCALE means one of `1', `2', `4', or `8', and it may always be +omitted along with the leading asterisk. + + The following additional addressing modes are understood: + +"Address Register Indirect" + `(%a0)' through `(%a7)' + `%a7' is also known as `%sp', i.e., the Stack Pointer. `%a6' is + also known as `%fp', the Frame Pointer. + +"Address Register Postincrement" + `(%a0)+' through `(%a7)+' + +"Address Register Predecrement" + `-(%a0)' through `-(%a7)' + +"Indirect Plus Offset" + `NUMBER(%A0)' through `NUMBER(%A7)', or `NUMBER(%PC)'. + + The NUMBER may also appear within the parentheses, as in + `(NUMBER,%A0)'. When used with the PC, the NUMBER may be omitted + (with an address register, omitting the NUMBER produces Address + Register Indirect mode). + +"Index" + `NUMBER(APC,REGISTER.SIZE*SCALE)' + + The NUMBER may be omitted, or it may appear within the + parentheses. The APC may be omitted. The REGISTER and the APC + may appear in either order. If both APC and REGISTER are address + registers, and the SIZE and SCALE are omitted, then the first + register is taken as the base register, and the second as the + index register. + +"Postindex" + `([NUMBER,APC],REGISTER.SIZE*SCALE,ONUMBER)' + + The ONUMBER, or the REGISTER, or both, may be omitted. Either the + NUMBER or the APC may be omitted, but not both. + +"Preindex" + `([NUMBER,APC,REGISTER.SIZE*SCALE],ONUMBER)' + + The NUMBER, or the APC, or the REGISTER, or any two of them, may + be omitted. The ONUMBER may be omitted. The REGISTER and the APC + may appear in either order. If both APC and REGISTER are address + registers, and the SIZE and SCALE are omitted, then the first + register is taken as the base register, and the second as the + index register. + + +File: as.info, Node: M68K-Float, Next: M68K-Directives, Prev: M68K-Moto-Syntax, Up: M68K-Dependent + +9.21.4 Floating Point +--------------------- + +Packed decimal (P) format floating literals are not supported. Feel +free to add the code! + + The floating point formats generated by directives are these. + +`.float' + `Single' precision floating point constants. + +`.double' + `Double' precision floating point constants. + +`.extend' +`.ldouble' + `Extended' precision (`long double') floating point constants. + + +File: as.info, Node: M68K-Directives, Next: M68K-opcodes, Prev: M68K-Float, Up: M68K-Dependent + +9.21.5 680x0 Machine Directives +------------------------------- + +In order to be compatible with the Sun assembler the 680x0 assembler +understands the following directives. + +`.data1' + This directive is identical to a `.data 1' directive. + +`.data2' + This directive is identical to a `.data 2' directive. + +`.even' + This directive is a special case of the `.align' directive; it + aligns the output to an even byte boundary. + +`.skip' + This directive is identical to a `.space' directive. + +`.arch NAME' + Select the target architecture and extension features. Valid + values for NAME are the same as for the `-march' command line + option. This directive cannot be specified after any instructions + have been assembled. If it is given multiple times, or in + conjunction with the `-march' option, all uses must be for the + same architecture and extension set. + +`.cpu NAME' + Select the target cpu. Valid valuse for NAME are the same as for + the `-mcpu' command line option. This directive cannot be + specified after any instructions have been assembled. If it is + given multiple times, or in conjunction with the `-mopt' option, + all uses must be for the same cpu. + + + +File: as.info, Node: M68K-opcodes, Prev: M68K-Directives, Up: M68K-Dependent + +9.21.6 Opcodes +-------------- + +* Menu: + +* M68K-Branch:: Branch Improvement +* M68K-Chars:: Special Characters + + +File: as.info, Node: M68K-Branch, Next: M68K-Chars, Up: M68K-opcodes + +9.21.6.1 Branch Improvement +........................... + +Certain pseudo opcodes are permitted for branch instructions. They +expand to the shortest branch instruction that reach the target. +Generally these mnemonics are made by substituting `j' for `b' at the +start of a Motorola mnemonic. + + The following table summarizes the pseudo-operations. A `*' flags +cases that are more fully described after the table: + + Displacement + +------------------------------------------------------------ + | 68020 68000/10, not PC-relative OK + Pseudo-Op |BYTE WORD LONG ABSOLUTE LONG JUMP ** + +------------------------------------------------------------ + jbsr |bsrs bsrw bsrl jsr + jra |bras braw bral jmp + * jXX |bXXs bXXw bXXl bNXs;jmp + * dbXX | N/A dbXXw dbXX;bras;bral dbXX;bras;jmp + fjXX | N/A fbXXw fbXXl N/A + + XX: condition + NX: negative of condition XX + `*'--see full description below + `**'--this expansion mode is disallowed by `--pcrel' + +`jbsr' +`jra' + These are the simplest jump pseudo-operations; they always map to + one particular machine instruction, depending on the displacement + to the branch target. This instruction will be a byte or word + branch is that is sufficient. Otherwise, a long branch will be + emitted if available. If no long branches are available and the + `--pcrel' option is not given, an absolute long jump will be + emitted instead. If no long branches are available, the `--pcrel' + option is given, and a word branch cannot reach the target, an + error message is generated. + + In addition to standard branch operands, `as' allows these + pseudo-operations to have all operands that are allowed for jsr + and jmp, substituting these instructions if the operand given is + not valid for a branch instruction. + +`jXX' + Here, `jXX' stands for an entire family of pseudo-operations, + where XX is a conditional branch or condition-code test. The full + list of pseudo-ops in this family is: + jhi jls jcc jcs jne jeq jvc + jvs jpl jmi jge jlt jgt jle + + Usually, each of these pseudo-operations expands to a single branch + instruction. However, if a word branch is not sufficient, no long + branches are available, and the `--pcrel' option is not given, `as' + issues a longer code fragment in terms of NX, the opposite + condition to XX. For example, under these conditions: + jXX foo + gives + bNXs oof + jmp foo + oof: + +`dbXX' + The full family of pseudo-operations covered here is + dbhi dbls dbcc dbcs dbne dbeq dbvc + dbvs dbpl dbmi dbge dblt dbgt dble + dbf dbra dbt + + Motorola `dbXX' instructions allow word displacements only. When + a word displacement is sufficient, each of these pseudo-operations + expands to the corresponding Motorola instruction. When a word + displacement is not sufficient and long branches are available, + when the source reads `dbXX foo', `as' emits + dbXX oo1 + bras oo2 + oo1:bral foo + oo2: + + If, however, long branches are not available and the `--pcrel' + option is not given, `as' emits + dbXX oo1 + bras oo2 + oo1:jmp foo + oo2: + +`fjXX' + This family includes + fjne fjeq fjge fjlt fjgt fjle fjf + fjt fjgl fjgle fjnge fjngl fjngle fjngt + fjnle fjnlt fjoge fjogl fjogt fjole fjolt + fjor fjseq fjsf fjsne fjst fjueq fjuge + fjugt fjule fjult fjun + + Each of these pseudo-operations always expands to a single Motorola + coprocessor branch instruction, word or long. All Motorola + coprocessor branch instructions allow both word and long + displacements. + + + +File: as.info, Node: M68K-Chars, Prev: M68K-Branch, Up: M68K-opcodes + +9.21.6.2 Special Characters +........................... + +The immediate character is `#' for Sun compatibility. The line-comment +character is `|' (unless the `--bitwise-or' option is used). If a `#' +appears at the beginning of a line, it is treated as a comment unless +it looks like `# line file', in which case it is treated normally. + + +File: as.info, Node: M68HC11-Dependent, Next: MicroBlaze-Dependent, Prev: M68K-Dependent, Up: Machine Dependencies + +9.22 M68HC11 and M68HC12 Dependent Features +=========================================== + +* Menu: + +* M68HC11-Opts:: M68HC11 and M68HC12 Options +* M68HC11-Syntax:: Syntax +* M68HC11-Modifiers:: Symbolic Operand Modifiers +* M68HC11-Directives:: Assembler Directives +* M68HC11-Float:: Floating Point +* M68HC11-opcodes:: Opcodes + + +File: as.info, Node: M68HC11-Opts, Next: M68HC11-Syntax, Up: M68HC11-Dependent + +9.22.1 M68HC11 and M68HC12 Options +---------------------------------- + +The Motorola 68HC11 and 68HC12 version of `as' have a few machine +dependent options. + +`-m68hc11' + This option switches the assembler in the M68HC11 mode. In this + mode, the assembler only accepts 68HC11 operands and mnemonics. It + produces code for the 68HC11. + +`-m68hc12' + This option switches the assembler in the M68HC12 mode. In this + mode, the assembler also accepts 68HC12 operands and mnemonics. It + produces code for the 68HC12. A few 68HC11 instructions are + replaced by some 68HC12 instructions as recommended by Motorola + specifications. + +`-m68hcs12' + This option switches the assembler in the M68HCS12 mode. This + mode is similar to `-m68hc12' but specifies to assemble for the + 68HCS12 series. The only difference is on the assembling of the + `movb' and `movw' instruction when a PC-relative operand is used. + +`-mshort' + This option controls the ABI and indicates to use a 16-bit integer + ABI. It has no effect on the assembled instructions. This is the + default. + +`-mlong' + This option controls the ABI and indicates to use a 32-bit integer + ABI. + +`-mshort-double' + This option controls the ABI and indicates to use a 32-bit float + ABI. This is the default. + +`-mlong-double' + This option controls the ABI and indicates to use a 64-bit float + ABI. + +`--strict-direct-mode' + You can use the `--strict-direct-mode' option to disable the + automatic translation of direct page mode addressing into extended + mode when the instruction does not support direct mode. For + example, the `clr' instruction does not support direct page mode + addressing. When it is used with the direct page mode, `as' will + ignore it and generate an absolute addressing. This option + prevents `as' from doing this, and the wrong usage of the direct + page mode will raise an error. + +`--short-branches' + The `--short-branches' option turns off the translation of + relative branches into absolute branches when the branch offset is + out of range. By default `as' transforms the relative branch + (`bsr', `bgt', `bge', `beq', `bne', `ble', `blt', `bhi', `bcc', + `bls', `bcs', `bmi', `bvs', `bvs', `bra') into an absolute branch + when the offset is out of the -128 .. 127 range. In that case, + the `bsr' instruction is translated into a `jsr', the `bra' + instruction is translated into a `jmp' and the conditional + branches instructions are inverted and followed by a `jmp'. This + option disables these translations and `as' will generate an error + if a relative branch is out of range. This option does not affect + the optimization associated to the `jbra', `jbsr' and `jbXX' + pseudo opcodes. + +`--force-long-branches' + The `--force-long-branches' option forces the translation of + relative branches into absolute branches. This option does not + affect the optimization associated to the `jbra', `jbsr' and + `jbXX' pseudo opcodes. + +`--print-insn-syntax' + You can use the `--print-insn-syntax' option to obtain the syntax + description of the instruction when an error is detected. + +`--print-opcodes' + The `--print-opcodes' option prints the list of all the + instructions with their syntax. The first item of each line + represents the instruction name and the rest of the line indicates + the possible operands for that instruction. The list is printed in + alphabetical order. Once the list is printed `as' exits. + +`--generate-example' + The `--generate-example' option is similar to `--print-opcodes' + but it generates an example for each instruction instead. + + +File: as.info, Node: M68HC11-Syntax, Next: M68HC11-Modifiers, Prev: M68HC11-Opts, Up: M68HC11-Dependent + +9.22.2 Syntax +------------- + +In the M68HC11 syntax, the instruction name comes first and it may be +followed by one or several operands (up to three). Operands are +separated by comma (`,'). In the normal mode, `as' will complain if too +many operands are specified for a given instruction. In the MRI mode +(turned on with `-M' option), it will treat them as comments. Example: + + inx + lda #23 + bset 2,x #4 + brclr *bot #8 foo + + The following addressing modes are understood for 68HC11 and 68HC12: +"Immediate" + `#NUMBER' + +"Address Register" + `NUMBER,X', `NUMBER,Y' + + The NUMBER may be omitted in which case 0 is assumed. + +"Direct Addressing mode" + `*SYMBOL', or `*DIGITS' + +"Absolute" + `SYMBOL', or `DIGITS' + + The M68HC12 has other more complex addressing modes. All of them are +supported and they are represented below: + +"Constant Offset Indexed Addressing Mode" + `NUMBER,REG' + + The NUMBER may be omitted in which case 0 is assumed. The + register can be either `X', `Y', `SP' or `PC'. The assembler will + use the smaller post-byte definition according to the constant + value (5-bit constant offset, 9-bit constant offset or 16-bit + constant offset). If the constant is not known by the assembler + it will use the 16-bit constant offset post-byte and the value + will be resolved at link time. + +"Offset Indexed Indirect" + `[NUMBER,REG]' + + The register can be either `X', `Y', `SP' or `PC'. + +"Auto Pre-Increment/Pre-Decrement/Post-Increment/Post-Decrement" + `NUMBER,-REG' `NUMBER,+REG' `NUMBER,REG-' `NUMBER,REG+' + + The number must be in the range `-8'..`+8' and must not be 0. The + register can be either `X', `Y', `SP' or `PC'. + +"Accumulator Offset" + `ACC,REG' + + The accumulator register can be either `A', `B' or `D'. The + register can be either `X', `Y', `SP' or `PC'. + +"Accumulator D offset indexed-indirect" + `[D,REG]' + + The register can be either `X', `Y', `SP' or `PC'. + + + For example: + + ldab 1024,sp + ldd [10,x] + orab 3,+x + stab -2,y- + ldx a,pc + sty [d,sp] + + +File: as.info, Node: M68HC11-Modifiers, Next: M68HC11-Directives, Prev: M68HC11-Syntax, Up: M68HC11-Dependent + +9.22.3 Symbolic Operand Modifiers +--------------------------------- + +The assembler supports several modifiers when using symbol addresses in +68HC11 and 68HC12 instruction operands. The general syntax is the +following: + + %modifier(symbol) + +`%addr' + This modifier indicates to the assembler and linker to use the + 16-bit physical address corresponding to the symbol. This is + intended to be used on memory window systems to map a symbol in + the memory bank window. If the symbol is in a memory expansion + part, the physical address corresponds to the symbol address + within the memory bank window. If the symbol is not in a memory + expansion part, this is the symbol address (using or not using the + %addr modifier has no effect in that case). + +`%page' + This modifier indicates to use the memory page number corresponding + to the symbol. If the symbol is in a memory expansion part, its + page number is computed by the linker as a number used to map the + page containing the symbol in the memory bank window. If the + symbol is not in a memory expansion part, the page number is 0. + +`%hi' + This modifier indicates to use the 8-bit high part of the physical + address of the symbol. + +`%lo' + This modifier indicates to use the 8-bit low part of the physical + address of the symbol. + + + For example a 68HC12 call to a function `foo_example' stored in +memory expansion part could be written as follows: + + call %addr(foo_example),%page(foo_example) + + and this is equivalent to + + call foo_example + + And for 68HC11 it could be written as follows: + + ldab #%page(foo_example) + stab _page_switch + jsr %addr(foo_example) + + +File: as.info, Node: M68HC11-Directives, Next: M68HC11-Float, Prev: M68HC11-Modifiers, Up: M68HC11-Dependent + +9.22.4 Assembler Directives +--------------------------- + +The 68HC11 and 68HC12 version of `as' have the following specific +assembler directives: + +`.relax' + The relax directive is used by the `GNU Compiler' to emit a + specific relocation to mark a group of instructions for linker + relaxation. The sequence of instructions within the group must be + known to the linker so that relaxation can be performed. + +`.mode [mshort|mlong|mshort-double|mlong-double]' + This directive specifies the ABI. It overrides the `-mshort', + `-mlong', `-mshort-double' and `-mlong-double' options. + +`.far SYMBOL' + This directive marks the symbol as a `far' symbol meaning that it + uses a `call/rtc' calling convention as opposed to `jsr/rts'. + During a final link, the linker will identify references to the + `far' symbol and will verify the proper calling convention. + +`.interrupt SYMBOL' + This directive marks the symbol as an interrupt entry point. This + information is then used by the debugger to correctly unwind the + frame across interrupts. + +`.xrefb SYMBOL' + This directive is defined for compatibility with the + `Specification for Motorola 8 and 16-Bit Assembly Language Input + Standard' and is ignored. + + + +File: as.info, Node: M68HC11-Float, Next: M68HC11-opcodes, Prev: M68HC11-Directives, Up: M68HC11-Dependent + +9.22.5 Floating Point +--------------------- + +Packed decimal (P) format floating literals are not supported. Feel +free to add the code! + + The floating point formats generated by directives are these. + +`.float' + `Single' precision floating point constants. + +`.double' + `Double' precision floating point constants. + +`.extend' +`.ldouble' + `Extended' precision (`long double') floating point constants. + + +File: as.info, Node: M68HC11-opcodes, Prev: M68HC11-Float, Up: M68HC11-Dependent + +9.22.6 Opcodes +-------------- + +* Menu: + +* M68HC11-Branch:: Branch Improvement + + +File: as.info, Node: M68HC11-Branch, Up: M68HC11-opcodes + +9.22.6.1 Branch Improvement +........................... + +Certain pseudo opcodes are permitted for branch instructions. They +expand to the shortest branch instruction that reach the target. +Generally these mnemonics are made by prepending `j' to the start of +Motorola mnemonic. These pseudo opcodes are not affected by the +`--short-branches' or `--force-long-branches' options. + + The following table summarizes the pseudo-operations. + + Displacement Width + +-------------------------------------------------------------+ + | Options | + | --short-branches --force-long-branches | + +--------------------------+----------------------------------+ + Op |BYTE WORD | BYTE WORD | + +--------------------------+----------------------------------+ + bsr | bsr <pc-rel> <error> | jsr <abs> | + bra | bra <pc-rel> <error> | jmp <abs> | + jbsr | bsr <pc-rel> jsr <abs> | bsr <pc-rel> jsr <abs> | + jbra | bra <pc-rel> jmp <abs> | bra <pc-rel> jmp <abs> | + bXX | bXX <pc-rel> <error> | bNX +3; jmp <abs> | + jbXX | bXX <pc-rel> bNX +3; | bXX <pc-rel> bNX +3; jmp <abs> | + | jmp <abs> | | + +--------------------------+----------------------------------+ + XX: condition + NX: negative of condition XX + +`jbsr' +`jbra' + These are the simplest jump pseudo-operations; they always map to + one particular machine instruction, depending on the displacement + to the branch target. + +`jbXX' + Here, `jbXX' stands for an entire family of pseudo-operations, + where XX is a conditional branch or condition-code test. The full + list of pseudo-ops in this family is: + jbcc jbeq jbge jbgt jbhi jbvs jbpl jblo + jbcs jbne jblt jble jbls jbvc jbmi + + For the cases of non-PC relative displacements and long + displacements, `as' issues a longer code fragment in terms of NX, + the opposite condition to XX. For example, for the non-PC + relative case: + jbXX foo + gives + bNXs oof + jmp foo + oof: + + + +File: as.info, Node: MicroBlaze-Dependent, Next: MIPS-Dependent, Prev: M68HC11-Dependent, Up: Machine Dependencies + +9.23 MicroBlaze Dependent Features +================================== + + The Xilinx MicroBlaze processor family includes several variants, +all using the same core instruction set. This chapter covers features +of the GNU assembler that are specific to the MicroBlaze architecture. +For details about the MicroBlaze instruction set, please see the +`MicroBlaze Processor Reference Guide (UG081)' available at +www.xilinx.com. + +* Menu: + +* MicroBlaze Directives:: Directives for MicroBlaze Processors. + + +File: as.info, Node: MicroBlaze Directives, Up: MicroBlaze-Dependent + +9.23.1 Directives +----------------- + +A number of assembler directives are available for MicroBlaze. + +`.data8 EXPRESSION,...' + This directive is an alias for `.byte'. Each expression is + assembled into an eight-bit value. + +`.data16 EXPRESSION,...' + This directive is an alias for `.hword'. Each expression is + assembled into an 16-bit value. + +`.data32 EXPRESSION,...' + This directive is an alias for `.word'. Each expression is + assembled into an 32-bit value. + +`.ent NAME[,LABEL]' + This directive is an alias for `.func' denoting the start of + function NAME at (optional) LABEL. + +`.end NAME[,LABEL]' + This directive is an alias for `.endfunc' denoting the end of + function NAME. + +`.gpword LABEL,...' + This directive is an alias for `.rva'. The resolved address of + LABEL is stored in the data section. + +`.weakext LABEL' + Declare that LABEL is a weak external symbol. + +`.rodata' + Switch to .rodata section. Equivalent to `.section .rodata' + +`.sdata2' + Switch to .sdata2 section. Equivalent to `.section .sdata2' + +`.sdata' + Switch to .sdata section. Equivalent to `.section .sdata' + +`.bss' + Switch to .bss section. Equivalent to `.section .bss' + +`.sbss' + Switch to .sbss section. Equivalent to `.section .sbss' + + +File: as.info, Node: MIPS-Dependent, Next: MMIX-Dependent, Prev: MicroBlaze-Dependent, Up: Machine Dependencies + +9.24 MIPS Dependent Features +============================ + + GNU `as' for MIPS architectures supports several different MIPS +processors, and MIPS ISA levels I through V, MIPS32, and MIPS64. For +information about the MIPS instruction set, see `MIPS RISC +Architecture', by Kane and Heindrich (Prentice-Hall). For an overview +of MIPS assembly conventions, see "Appendix D: Assembly Language +Programming" in the same work. + +* Menu: + +* MIPS Opts:: Assembler options +* MIPS Object:: ECOFF object code +* MIPS Stabs:: Directives for debugging information +* MIPS ISA:: Directives to override the ISA level +* MIPS symbol sizes:: Directives to override the size of symbols +* MIPS autoextend:: Directives for extending MIPS 16 bit instructions +* MIPS insn:: Directive to mark data as an instruction +* MIPS option stack:: Directives to save and restore options +* MIPS ASE instruction generation overrides:: Directives to control + generation of MIPS ASE instructions +* MIPS floating-point:: Directives to override floating-point options + + +File: as.info, Node: MIPS Opts, Next: MIPS Object, Up: MIPS-Dependent + +9.24.1 Assembler options +------------------------ + +The MIPS configurations of GNU `as' support these special options: + +`-G NUM' + This option sets the largest size of an object that can be + referenced implicitly with the `gp' register. It is only accepted + for targets that use ECOFF format. The default value is 8. + +`-EB' +`-EL' + Any MIPS configuration of `as' can select big-endian or + little-endian output at run time (unlike the other GNU development + tools, which must be configured for one or the other). Use `-EB' + to select big-endian output, and `-EL' for little-endian. + +`-KPIC' + Generate SVR4-style PIC. This option tells the assembler to + generate SVR4-style position-independent macro expansions. It + also tells the assembler to mark the output file as PIC. + +`-mvxworks-pic' + Generate VxWorks PIC. This option tells the assembler to generate + VxWorks-style position-independent macro expansions. + +`-mips1' +`-mips2' +`-mips3' +`-mips4' +`-mips5' +`-mips32' +`-mips32r2' +`-mips64' +`-mips64r2' + Generate code for a particular MIPS Instruction Set Architecture + level. `-mips1' corresponds to the R2000 and R3000 processors, + `-mips2' to the R6000 processor, `-mips3' to the R4000 processor, + and `-mips4' to the R8000 and R10000 processors. `-mips5', + `-mips32', `-mips32r2', `-mips64', and `-mips64r2' correspond to + generic MIPS V, MIPS32, MIPS32 RELEASE 2, MIPS64, and MIPS64 + RELEASE 2 ISA processors, respectively. You can also switch + instruction sets during the assembly; see *Note Directives to + override the ISA level: MIPS ISA. + +`-mgp32' +`-mfp32' + Some macros have different expansions for 32-bit and 64-bit + registers. The register sizes are normally inferred from the ISA + and ABI, but these flags force a certain group of registers to be + treated as 32 bits wide at all times. `-mgp32' controls the size + of general-purpose registers and `-mfp32' controls the size of + floating-point registers. + + The `.set gp=32' and `.set fp=32' directives allow the size of + registers to be changed for parts of an object. The default value + is restored by `.set gp=default' and `.set fp=default'. + + On some MIPS variants there is a 32-bit mode flag; when this flag + is set, 64-bit instructions generate a trap. Also, some 32-bit + OSes only save the 32-bit registers on a context switch, so it is + essential never to use the 64-bit registers. + +`-mgp64' +`-mfp64' + Assume that 64-bit registers are available. This is provided in + the interests of symmetry with `-mgp32' and `-mfp32'. + + The `.set gp=64' and `.set fp=64' directives allow the size of + registers to be changed for parts of an object. The default value + is restored by `.set gp=default' and `.set fp=default'. + +`-mips16' +`-no-mips16' + Generate code for the MIPS 16 processor. This is equivalent to + putting `.set mips16' at the start of the assembly file. + `-no-mips16' turns off this option. + +`-msmartmips' +`-mno-smartmips' + Enables the SmartMIPS extensions to the MIPS32 instruction set, + which provides a number of new instructions which target smartcard + and cryptographic applications. This is equivalent to putting + `.set smartmips' at the start of the assembly file. + `-mno-smartmips' turns off this option. + +`-mips3d' +`-no-mips3d' + Generate code for the MIPS-3D Application Specific Extension. + This tells the assembler to accept MIPS-3D instructions. + `-no-mips3d' turns off this option. + +`-mdmx' +`-no-mdmx' + Generate code for the MDMX Application Specific Extension. This + tells the assembler to accept MDMX instructions. `-no-mdmx' turns + off this option. + +`-mdsp' +`-mno-dsp' + Generate code for the DSP Release 1 Application Specific Extension. + This tells the assembler to accept DSP Release 1 instructions. + `-mno-dsp' turns off this option. + +`-mdspr2' +`-mno-dspr2' + Generate code for the DSP Release 2 Application Specific Extension. + This option implies -mdsp. This tells the assembler to accept DSP + Release 2 instructions. `-mno-dspr2' turns off this option. + +`-mmt' +`-mno-mt' + Generate code for the MT Application Specific Extension. This + tells the assembler to accept MT instructions. `-mno-mt' turns + off this option. + +`-mfix7000' +`-mno-fix7000' + Cause nops to be inserted if the read of the destination register + of an mfhi or mflo instruction occurs in the following two + instructions. + +`-mfix-vr4120' +`-no-mfix-vr4120' + Insert nops to work around certain VR4120 errata. This option is + intended to be used on GCC-generated code: it is not designed to + catch all problems in hand-written assembler code. + +`-mfix-vr4130' +`-no-mfix-vr4130' + Insert nops to work around the VR4130 `mflo'/`mfhi' errata. + +`-mfix-24k' +`-no-mfix-24k' + Insert nops to work around the 24K `eret'/`deret' errata. + +`-m4010' +`-no-m4010' + Generate code for the LSI R4010 chip. This tells the assembler to + accept the R4010 specific instructions (`addciu', `ffc', etc.), + and to not schedule `nop' instructions around accesses to the `HI' + and `LO' registers. `-no-m4010' turns off this option. + +`-m4650' +`-no-m4650' + Generate code for the MIPS R4650 chip. This tells the assembler + to accept the `mad' and `madu' instruction, and to not schedule + `nop' instructions around accesses to the `HI' and `LO' registers. + `-no-m4650' turns off this option. + +`-m3900' +`-no-m3900' +`-m4100' +`-no-m4100' + For each option `-mNNNN', generate code for the MIPS RNNNN chip. + This tells the assembler to accept instructions specific to that + chip, and to schedule for that chip's hazards. + +`-march=CPU' + Generate code for a particular MIPS cpu. It is exactly equivalent + to `-mCPU', except that there are more value of CPU understood. + Valid CPU value are: + + 2000, 3000, 3900, 4000, 4010, 4100, 4111, vr4120, vr4130, + vr4181, 4300, 4400, 4600, 4650, 5000, rm5200, rm5230, rm5231, + rm5261, rm5721, vr5400, vr5500, 6000, rm7000, 8000, rm9000, + 10000, 12000, 14000, 16000, 4kc, 4km, 4kp, 4ksc, 4kec, 4kem, + 4kep, 4ksd, m4k, m4kp, 24kc, 24kf2_1, 24kf, 24kf1_1, 24kec, + 24kef2_1, 24kef, 24kef1_1, 34kc, 34kf2_1, 34kf, 34kf1_1, 74kc, + 74kf2_1, 74kf, 74kf1_1, 74kf3_2, 1004kc, 1004kf2_1, 1004kf, + 1004kf1_1, 5kc, 5kf, 20kc, 25kf, sb1, sb1a, loongson2e, + loongson2f, octeon, xlr + + For compatibility reasons, `Nx' and `Bfx' are accepted as synonyms + for `Nf1_1'. These values are deprecated. + +`-mtune=CPU' + Schedule and tune for a particular MIPS cpu. Valid CPU values are + identical to `-march=CPU'. + +`-mabi=ABI' + Record which ABI the source code uses. The recognized arguments + are: `32', `n32', `o64', `64' and `eabi'. + +`-msym32' +`-mno-sym32' + Equivalent to adding `.set sym32' or `.set nosym32' to the + beginning of the assembler input. *Note MIPS symbol sizes::. + +`-nocpp' + This option is ignored. It is accepted for command-line + compatibility with other assemblers, which use it to turn off C + style preprocessing. With GNU `as', there is no need for + `-nocpp', because the GNU assembler itself never runs the C + preprocessor. + +`-msoft-float' +`-mhard-float' + Disable or enable floating-point instructions. Note that by + default floating-point instructions are always allowed even with + CPU targets that don't have support for these instructions. + +`-msingle-float' +`-mdouble-float' + Disable or enable double-precision floating-point operations. Note + that by default double-precision floating-point operations are + always allowed even with CPU targets that don't have support for + these operations. + +`--construct-floats' +`--no-construct-floats' + The `--no-construct-floats' option disables the construction of + double width floating point constants by loading the two halves of + the value into the two single width floating point registers that + make up the double width register. This feature is useful if the + processor support the FR bit in its status register, and this bit + is known (by the programmer) to be set. This bit prevents the + aliasing of the double width register by the single width + registers. + + By default `--construct-floats' is selected, allowing construction + of these floating point constants. + +`--trap' +`--no-break' + `as' automatically macro expands certain division and + multiplication instructions to check for overflow and division by + zero. This option causes `as' to generate code to take a trap + exception rather than a break exception when an error is detected. + The trap instructions are only supported at Instruction Set + Architecture level 2 and higher. + +`--break' +`--no-trap' + Generate code to take a break exception rather than a trap + exception when an error is detected. This is the default. + +`-mpdr' +`-mno-pdr' + Control generation of `.pdr' sections. Off by default on IRIX, on + elsewhere. + +`-mshared' +`-mno-shared' + When generating code using the Unix calling conventions (selected + by `-KPIC' or `-mcall_shared'), gas will normally generate code + which can go into a shared library. The `-mno-shared' option + tells gas to generate code which uses the calling convention, but + can not go into a shared library. The resulting code is slightly + more efficient. This option only affects the handling of the + `.cpload' and `.cpsetup' pseudo-ops. + + +File: as.info, Node: MIPS Object, Next: MIPS Stabs, Prev: MIPS Opts, Up: MIPS-Dependent + +9.24.2 MIPS ECOFF object code +----------------------------- + +Assembling for a MIPS ECOFF target supports some additional sections +besides the usual `.text', `.data' and `.bss'. The additional sections +are `.rdata', used for read-only data, `.sdata', used for small data, +and `.sbss', used for small common objects. + + When assembling for ECOFF, the assembler uses the `$gp' (`$28') +register to form the address of a "small object". Any object in the +`.sdata' or `.sbss' sections is considered "small" in this sense. For +external objects, or for objects in the `.bss' section, you can use the +`gcc' `-G' option to control the size of objects addressed via `$gp'; +the default value is 8, meaning that a reference to any object eight +bytes or smaller uses `$gp'. Passing `-G 0' to `as' prevents it from +using the `$gp' register on the basis of object size (but the assembler +uses `$gp' for objects in `.sdata' or `sbss' in any case). The size of +an object in the `.bss' section is set by the `.comm' or `.lcomm' +directive that defines it. The size of an external object may be set +with the `.extern' directive. For example, `.extern sym,4' declares +that the object at `sym' is 4 bytes in length, whie leaving `sym' +otherwise undefined. + + Using small ECOFF objects requires linker support, and assumes that +the `$gp' register is correctly initialized (normally done +automatically by the startup code). MIPS ECOFF assembly code must not +modify the `$gp' register. + + +File: as.info, Node: MIPS Stabs, Next: MIPS ISA, Prev: MIPS Object, Up: MIPS-Dependent + +9.24.3 Directives for debugging information +------------------------------------------- + +MIPS ECOFF `as' supports several directives used for generating +debugging information which are not support by traditional MIPS +assemblers. These are `.def', `.endef', `.dim', `.file', `.scl', +`.size', `.tag', `.type', `.val', `.stabd', `.stabn', and `.stabs'. +The debugging information generated by the three `.stab' directives can +only be read by GDB, not by traditional MIPS debuggers (this +enhancement is required to fully support C++ debugging). These +directives are primarily used by compilers, not assembly language +programmers! + + +File: as.info, Node: MIPS symbol sizes, Next: MIPS autoextend, Prev: MIPS ISA, Up: MIPS-Dependent + +9.24.4 Directives to override the size of symbols +------------------------------------------------- + +The n64 ABI allows symbols to have any 64-bit value. Although this +provides a great deal of flexibility, it means that some macros have +much longer expansions than their 32-bit counterparts. For example, +the non-PIC expansion of `dla $4,sym' is usually: + + lui $4,%highest(sym) + lui $1,%hi(sym) + daddiu $4,$4,%higher(sym) + daddiu $1,$1,%lo(sym) + dsll32 $4,$4,0 + daddu $4,$4,$1 + + whereas the 32-bit expansion is simply: + + lui $4,%hi(sym) + daddiu $4,$4,%lo(sym) + + n64 code is sometimes constructed in such a way that all symbolic +constants are known to have 32-bit values, and in such cases, it's +preferable to use the 32-bit expansion instead of the 64-bit expansion. + + You can use the `.set sym32' directive to tell the assembler that, +from this point on, all expressions of the form `SYMBOL' or `SYMBOL + +OFFSET' have 32-bit values. For example: + + .set sym32 + dla $4,sym + lw $4,sym+16 + sw $4,sym+0x8000($4) + + will cause the assembler to treat `sym', `sym+16' and `sym+0x8000' +as 32-bit values. The handling of non-symbolic addresses is not +affected. + + The directive `.set nosym32' ends a `.set sym32' block and reverts +to the normal behavior. It is also possible to change the symbol size +using the command-line options `-msym32' and `-mno-sym32'. + + These options and directives are always accepted, but at present, +they have no effect for anything other than n64. + + +File: as.info, Node: MIPS ISA, Next: MIPS symbol sizes, Prev: MIPS Stabs, Up: MIPS-Dependent + +9.24.5 Directives to override the ISA level +------------------------------------------- + +GNU `as' supports an additional directive to change the MIPS +Instruction Set Architecture level on the fly: `.set mipsN'. N should +be a number from 0 to 5, or 32, 32r2, 64 or 64r2. The values other +than 0 make the assembler accept instructions for the corresponding ISA +level, from that point on in the assembly. `.set mipsN' affects not +only which instructions are permitted, but also how certain macros are +expanded. `.set mips0' restores the ISA level to its original level: +either the level you selected with command line options, or the default +for your configuration. You can use this feature to permit specific +MIPS3 instructions while assembling in 32 bit mode. Use this directive +with care! + + The `.set arch=CPU' directive provides even finer control. It +changes the effective CPU target and allows the assembler to use +instructions specific to a particular CPU. All CPUs supported by the +`-march' command line option are also selectable by this directive. +The original value is restored by `.set arch=default'. + + The directive `.set mips16' puts the assembler into MIPS 16 mode, in +which it will assemble instructions for the MIPS 16 processor. Use +`.set nomips16' to return to normal 32 bit mode. + + Traditional MIPS assemblers do not support this directive. + + +File: as.info, Node: MIPS autoextend, Next: MIPS insn, Prev: MIPS symbol sizes, Up: MIPS-Dependent + +9.24.6 Directives for extending MIPS 16 bit instructions +-------------------------------------------------------- + +By default, MIPS 16 instructions are automatically extended to 32 bits +when necessary. The directive `.set noautoextend' will turn this off. +When `.set noautoextend' is in effect, any 32 bit instruction must be +explicitly extended with the `.e' modifier (e.g., `li.e $4,1000'). The +directive `.set autoextend' may be used to once again automatically +extend instructions when necessary. + + This directive is only meaningful when in MIPS 16 mode. Traditional +MIPS assemblers do not support this directive. + + +File: as.info, Node: MIPS insn, Next: MIPS option stack, Prev: MIPS autoextend, Up: MIPS-Dependent + +9.24.7 Directive to mark data as an instruction +----------------------------------------------- + +The `.insn' directive tells `as' that the following data is actually +instructions. This makes a difference in MIPS 16 mode: when loading +the address of a label which precedes instructions, `as' automatically +adds 1 to the value, so that jumping to the loaded address will do the +right thing. + + The `.global' and `.globl' directives supported by `as' will by +default mark the symbol as pointing to a region of data not code. This +means that, for example, any instructions following such a symbol will +not be disassembled by `objdump' as it will regard them as data. To +change this behaviour an optional section name can be placed after the +symbol name in the `.global' directive. If this section exists and is +known to be a code section, then the symbol will be marked as poiting at +code not data. Ie the syntax for the directive is: + + `.global SYMBOL[ SECTION][, SYMBOL[ SECTION]] ...', + + Here is a short example: + + .global foo .text, bar, baz .data + foo: + nop + bar: + .word 0x0 + baz: + .word 0x1 + + +File: as.info, Node: MIPS option stack, Next: MIPS ASE instruction generation overrides, Prev: MIPS insn, Up: MIPS-Dependent + +9.24.8 Directives to save and restore options +--------------------------------------------- + +The directives `.set push' and `.set pop' may be used to save and +restore the current settings for all the options which are controlled +by `.set'. The `.set push' directive saves the current settings on a +stack. The `.set pop' directive pops the stack and restores the +settings. + + These directives can be useful inside an macro which must change an +option such as the ISA level or instruction reordering but does not want +to change the state of the code which invoked the macro. + + Traditional MIPS assemblers do not support these directives. + + +File: as.info, Node: MIPS ASE instruction generation overrides, Next: MIPS floating-point, Prev: MIPS option stack, Up: MIPS-Dependent + +9.24.9 Directives to control generation of MIPS ASE instructions +---------------------------------------------------------------- + +The directive `.set mips3d' makes the assembler accept instructions +from the MIPS-3D Application Specific Extension from that point on in +the assembly. The `.set nomips3d' directive prevents MIPS-3D +instructions from being accepted. + + The directive `.set smartmips' makes the assembler accept +instructions from the SmartMIPS Application Specific Extension to the +MIPS32 ISA from that point on in the assembly. The `.set nosmartmips' +directive prevents SmartMIPS instructions from being accepted. + + The directive `.set mdmx' makes the assembler accept instructions +from the MDMX Application Specific Extension from that point on in the +assembly. The `.set nomdmx' directive prevents MDMX instructions from +being accepted. + + The directive `.set dsp' makes the assembler accept instructions +from the DSP Release 1 Application Specific Extension from that point +on in the assembly. The `.set nodsp' directive prevents DSP Release 1 +instructions from being accepted. + + The directive `.set dspr2' makes the assembler accept instructions +from the DSP Release 2 Application Specific Extension from that point +on in the assembly. This dirctive implies `.set dsp'. The `.set +nodspr2' directive prevents DSP Release 2 instructions from being +accepted. + + The directive `.set mt' makes the assembler accept instructions from +the MT Application Specific Extension from that point on in the +assembly. The `.set nomt' directive prevents MT instructions from +being accepted. + + Traditional MIPS assemblers do not support these directives. + + +File: as.info, Node: MIPS floating-point, Prev: MIPS ASE instruction generation overrides, Up: MIPS-Dependent + +9.24.10 Directives to override floating-point options +----------------------------------------------------- + +The directives `.set softfloat' and `.set hardfloat' provide finer +control of disabling and enabling float-point instructions. These +directives always override the default (that hard-float instructions +are accepted) or the command-line options (`-msoft-float' and +`-mhard-float'). + + The directives `.set singlefloat' and `.set doublefloat' provide +finer control of disabling and enabling double-precision float-point +operations. These directives always override the default (that +double-precision operations are accepted) or the command-line options +(`-msingle-float' and `-mdouble-float'). + + Traditional MIPS assemblers do not support these directives. + + +File: as.info, Node: MMIX-Dependent, Next: MSP430-Dependent, Prev: MIPS-Dependent, Up: Machine Dependencies + +9.25 MMIX Dependent Features +============================ + +* Menu: + +* MMIX-Opts:: Command-line Options +* MMIX-Expand:: Instruction expansion +* MMIX-Syntax:: Syntax +* MMIX-mmixal:: Differences to `mmixal' syntax and semantics + + +File: as.info, Node: MMIX-Opts, Next: MMIX-Expand, Up: MMIX-Dependent + +9.25.1 Command-line Options +--------------------------- + +The MMIX version of `as' has some machine-dependent options. + + When `--fixed-special-register-names' is specified, only the register +names specified in *Note MMIX-Regs:: are recognized in the instructions +`PUT' and `GET'. + + You can use the `--globalize-symbols' to make all symbols global. +This option is useful when splitting up a `mmixal' program into several +files. + + The `--gnu-syntax' turns off most syntax compatibility with +`mmixal'. Its usability is currently doubtful. + + The `--relax' option is not fully supported, but will eventually make +the object file prepared for linker relaxation. + + If you want to avoid inadvertently calling a predefined symbol and +would rather get an error, for example when using `as' with a compiler +or other machine-generated code, specify `--no-predefined-syms'. This +turns off built-in predefined definitions of all such symbols, +including rounding-mode symbols, segment symbols, `BIT' symbols, and +`TRAP' symbols used in `mmix' "system calls". It also turns off +predefined special-register names, except when used in `PUT' and `GET' +instructions. + + By default, some instructions are expanded to fit the size of the +operand or an external symbol (*note MMIX-Expand::). By passing +`--no-expand', no such expansion will be done, instead causing errors +at link time if the operand does not fit. + + The `mmixal' documentation (*note mmixsite::) specifies that global +registers allocated with the `GREG' directive (*note MMIX-greg::) and +initialized to the same non-zero value, will refer to the same global +register. This isn't strictly enforceable in `as' since the final +addresses aren't known until link-time, but it will do an effort unless +the `--no-merge-gregs' option is specified. (Register merging isn't +yet implemented in `ld'.) + + `as' will warn every time it expands an instruction to fit an +operand unless the option `-x' is specified. It is believed that this +behaviour is more useful than just mimicking `mmixal''s behaviour, in +which instructions are only expanded if the `-x' option is specified, +and assembly fails otherwise, when an instruction needs to be expanded. +It needs to be kept in mind that `mmixal' is both an assembler and +linker, while `as' will expand instructions that at link stage can be +contracted. (Though linker relaxation isn't yet implemented in `ld'.) +The option `-x' also imples `--linker-allocated-gregs'. + + If instruction expansion is enabled, `as' can expand a `PUSHJ' +instruction into a series of instructions. The shortest expansion is +to not expand it, but just mark the call as redirectable to a stub, +which `ld' creates at link-time, but only if the original `PUSHJ' +instruction is found not to reach the target. The stub consists of the +necessary instructions to form a jump to the target. This happens if +`as' can assert that the `PUSHJ' instruction can reach such a stub. +The option `--no-pushj-stubs' disables this shorter expansion, and the +longer series of instructions is then created at assembly-time. The +option `--no-stubs' is a synonym, intended for compatibility with +future releases, where generation of stubs for other instructions may +be implemented. + + Usually a two-operand-expression (*note GREG-base::) without a +matching `GREG' directive is treated as an error by `as'. When the +option `--linker-allocated-gregs' is in effect, they are instead passed +through to the linker, which will allocate as many global registers as +is needed. + + +File: as.info, Node: MMIX-Expand, Next: MMIX-Syntax, Prev: MMIX-Opts, Up: MMIX-Dependent + +9.25.2 Instruction expansion +---------------------------- + +When `as' encounters an instruction with an operand that is either not +known or does not fit the operand size of the instruction, `as' (and +`ld') will expand the instruction into a sequence of instructions +semantically equivalent to the operand fitting the instruction. +Expansion will take place for the following instructions: + +`GETA' + Expands to a sequence of four instructions: `SETL', `INCML', + `INCMH' and `INCH'. The operand must be a multiple of four. + +Conditional branches + A branch instruction is turned into a branch with the complemented + condition and prediction bit over five instructions; four + instructions setting `$255' to the operand value, which like with + `GETA' must be a multiple of four, and a final `GO $255,$255,0'. + +`PUSHJ' + Similar to expansion for conditional branches; four instructions + set `$255' to the operand value, followed by a `PUSHGO + $255,$255,0'. + +`JMP' + Similar to conditional branches and `PUSHJ'. The final instruction + is `GO $255,$255,0'. + + The linker `ld' is expected to shrink these expansions for code +assembled with `--relax' (though not currently implemented). + + +File: as.info, Node: MMIX-Syntax, Next: MMIX-mmixal, Prev: MMIX-Expand, Up: MMIX-Dependent + +9.25.3 Syntax +------------- + +The assembly syntax is supposed to be upward compatible with that +described in Sections 1.3 and 1.4 of `The Art of Computer Programming, +Volume 1'. Draft versions of those chapters as well as other MMIX +information is located at +`http://www-cs-faculty.stanford.edu/~knuth/mmix-news.html'. Most code +examples from the mmixal package located there should work unmodified +when assembled and linked as single files, with a few noteworthy +exceptions (*note MMIX-mmixal::). + + Before an instruction is emitted, the current location is aligned to +the next four-byte boundary. If a label is defined at the beginning of +the line, its value will be the aligned value. + + In addition to the traditional hex-prefix `0x', a hexadecimal number +can also be specified by the prefix character `#'. + + After all operands to an MMIX instruction or directive have been +specified, the rest of the line is ignored, treated as a comment. + +* Menu: + +* MMIX-Chars:: Special Characters +* MMIX-Symbols:: Symbols +* MMIX-Regs:: Register Names +* MMIX-Pseudos:: Assembler Directives + + +File: as.info, Node: MMIX-Chars, Next: MMIX-Symbols, Up: MMIX-Syntax + +9.25.3.1 Special Characters +........................... + +The characters `*' and `#' are line comment characters; each start a +comment at the beginning of a line, but only at the beginning of a +line. A `#' prefixes a hexadecimal number if found elsewhere on a line. + + Two other characters, `%' and `!', each start a comment anywhere on +the line. Thus you can't use the `modulus' and `not' operators in +expressions normally associated with these two characters. + + A `;' is a line separator, treated as a new-line, so separate +instructions can be specified on a single line. + + +File: as.info, Node: MMIX-Symbols, Next: MMIX-Regs, Prev: MMIX-Chars, Up: MMIX-Syntax + +9.25.3.2 Symbols +................ + +The character `:' is permitted in identifiers. There are two +exceptions to it being treated as any other symbol character: if a +symbol begins with `:', it means that the symbol is in the global +namespace and that the current prefix should not be prepended to that +symbol (*note MMIX-prefix::). The `:' is then not considered part of +the symbol. For a symbol in the label position (first on a line), a `:' +at the end of a symbol is silently stripped off. A label is permitted, +but not required, to be followed by a `:', as with many other assembly +formats. + + The character `@' in an expression, is a synonym for `.', the +current location. + + In addition to the common forward and backward local symbol formats +(*note Symbol Names::), they can be specified with upper-case `B' and +`F', as in `8B' and `9F'. A local label defined for the current +position is written with a `H' appended to the number: + 3H LDB $0,$1,2 + This and traditional local-label formats cannot be mixed: a label +must be defined and referred to using the same format. + + There's a minor caveat: just as for the ordinary local symbols, the +local symbols are translated into ordinary symbols using control +characters are to hide the ordinal number of the symbol. +Unfortunately, these symbols are not translated back in error messages. +Thus you may see confusing error messages when local symbols are used. +Control characters `\003' (control-C) and `\004' (control-D) are used +for the MMIX-specific local-symbol syntax. + + The symbol `Main' is handled specially; it is always global. + + By defining the symbols `__.MMIX.start..text' and +`__.MMIX.start..data', the address of respectively the `.text' and +`.data' segments of the final program can be defined, though when +linking more than one object file, the code or data in the object file +containing the symbol is not guaranteed to be start at that position; +just the final executable. *Note MMIX-loc::. + + +File: as.info, Node: MMIX-Regs, Next: MMIX-Pseudos, Prev: MMIX-Symbols, Up: MMIX-Syntax + +9.25.3.3 Register names +....................... + +Local and global registers are specified as `$0' to `$255'. The +recognized special register names are `rJ', `rA', `rB', `rC', `rD', +`rE', `rF', `rG', `rH', `rI', `rK', `rL', `rM', `rN', `rO', `rP', `rQ', +`rR', `rS', `rT', `rU', `rV', `rW', `rX', `rY', `rZ', `rBB', `rTT', +`rWW', `rXX', `rYY' and `rZZ'. A leading `:' is optional for special +register names. + + Local and global symbols can be equated to register names and used in +place of ordinary registers. + + Similarly for special registers, local and global symbols can be +used. Also, symbols equated from numbers and constant expressions are +allowed in place of a special register, except when either of the +options `--no-predefined-syms' and `--fixed-special-register-names' are +specified. Then only the special register names above are allowed for +the instructions having a special register operand; `GET' and `PUT'. + + +File: as.info, Node: MMIX-Pseudos, Prev: MMIX-Regs, Up: MMIX-Syntax + +9.25.3.4 Assembler Directives +............................. + +`LOC' + The `LOC' directive sets the current location to the value of the + operand field, which may include changing sections. If the + operand is a constant, the section is set to either `.data' if the + value is `0x2000000000000000' or larger, else it is set to `.text'. + Within a section, the current location may only be changed to + monotonically higher addresses. A LOC expression must be a + previously defined symbol or a "pure" constant. + + An example, which sets the label PREV to the current location, and + updates the current location to eight bytes forward: + prev LOC @+8 + + When a LOC has a constant as its operand, a symbol + `__.MMIX.start..text' or `__.MMIX.start..data' is defined + depending on the address as mentioned above. Each such symbol is + interpreted as special by the linker, locating the section at that + address. Note that if multiple files are linked, the first object + file with that section will be mapped to that address (not + necessarily the file with the LOC definition). + +`LOCAL' + Example: + LOCAL external_symbol + LOCAL 42 + .local asymbol + + This directive-operation generates a link-time assertion that the + operand does not correspond to a global register. The operand is + an expression that at link-time resolves to a register symbol or a + number. A number is treated as the register having that number. + There is one restriction on the use of this directive: the + pseudo-directive must be placed in a section with contents, code + or data. + +`IS' + The `IS' directive: + asymbol IS an_expression + sets the symbol `asymbol' to `an_expression'. A symbol may not be + set more than once using this directive. Local labels may be set + using this directive, for example: + 5H IS @+4 + +`GREG' + This directive reserves a global register, gives it an initial + value and optionally gives it a symbolic name. Some examples: + + areg GREG + breg GREG data_value + GREG data_buffer + .greg creg, another_data_value + + The symbolic register name can be used in place of a (non-special) + register. If a value isn't provided, it defaults to zero. Unless + the option `--no-merge-gregs' is specified, non-zero registers + allocated with this directive may be eliminated by `as'; another + register with the same value used in its place. Any of the + instructions `CSWAP', `GO', `LDA', `LDBU', `LDB', `LDHT', `LDOU', + `LDO', `LDSF', `LDTU', `LDT', `LDUNC', `LDVTS', `LDWU', `LDW', + `PREGO', `PRELD', `PREST', `PUSHGO', `STBU', `STB', `STCO', `STHT', + `STOU', `STSF', `STTU', `STT', `STUNC', `SYNCD', `SYNCID', can + have a value nearby an initial value in place of its second and + third operands. Here, "nearby" is defined as within the range + 0...255 from the initial value of such an allocated register. + + buffer1 BYTE 0,0,0,0,0 + buffer2 BYTE 0,0,0,0,0 + ... + GREG buffer1 + LDOU $42,buffer2 + In the example above, the `Y' field of the `LDOUI' instruction + (LDOU with a constant Z) will be replaced with the global register + allocated for `buffer1', and the `Z' field will have the value 5, + the offset from `buffer1' to `buffer2'. The result is equivalent + to this code: + buffer1 BYTE 0,0,0,0,0 + buffer2 BYTE 0,0,0,0,0 + ... + tmpreg GREG buffer1 + LDOU $42,tmpreg,(buffer2-buffer1) + + Global registers allocated with this directive are allocated in + order higher-to-lower within a file. Other than that, the exact + order of register allocation and elimination is undefined. For + example, the order is undefined when more than one file with such + directives are linked together. With the options `-x' and + `--linker-allocated-gregs', `GREG' directives for two-operand + cases like the one mentioned above can be omitted. Sufficient + global registers will then be allocated by the linker. + +`BYTE' + The `BYTE' directive takes a series of operands separated by a + comma. If an operand is a string (*note Strings::), each + character of that string is emitted as a byte. Other operands + must be constant expressions without forward references, in the + range 0...255. If you need operands having expressions with + forward references, use `.byte' (*note Byte::). An operand can be + omitted, defaulting to a zero value. + +`WYDE' +`TETRA' +`OCTA' + The directives `WYDE', `TETRA' and `OCTA' emit constants of two, + four and eight bytes size respectively. Before anything else + happens for the directive, the current location is aligned to the + respective constant-size boundary. If a label is defined at the + beginning of the line, its value will be that after the alignment. + A single operand can be omitted, defaulting to a zero value + emitted for the directive. Operands can be expressed as strings + (*note Strings::), in which case each character in the string is + emitted as a separate constant of the size indicated by the + directive. + +`PREFIX' + The `PREFIX' directive sets a symbol name prefix to be prepended to + all symbols (except local symbols, *note MMIX-Symbols::), that are + not prefixed with `:', until the next `PREFIX' directive. Such + prefixes accumulate. For example, + PREFIX a + PREFIX b + c IS 0 + defines a symbol `abc' with the value 0. + +`BSPEC' +`ESPEC' + A pair of `BSPEC' and `ESPEC' directives delimit a section of + special contents (without specified semantics). Example: + BSPEC 42 + TETRA 1,2,3 + ESPEC + The single operand to `BSPEC' must be number in the range 0...255. + The `BSPEC' number 80 is used by the GNU binutils implementation. + + +File: as.info, Node: MMIX-mmixal, Prev: MMIX-Syntax, Up: MMIX-Dependent + +9.25.4 Differences to `mmixal' +------------------------------ + +The binutils `as' and `ld' combination has a few differences in +function compared to `mmixal' (*note mmixsite::). + + The replacement of a symbol with a GREG-allocated register (*note +GREG-base::) is not handled the exactly same way in `as' as in +`mmixal'. This is apparent in the `mmixal' example file `inout.mms', +where different registers with different offsets, eventually yielding +the same address, are used in the first instruction. This type of +difference should however not affect the function of any program unless +it has specific assumptions about the allocated register number. + + Line numbers (in the `mmo' object format) are currently not +supported. + + Expression operator precedence is not that of mmixal: operator +precedence is that of the C programming language. It's recommended to +use parentheses to explicitly specify wanted operator precedence +whenever more than one type of operators are used. + + The serialize unary operator `&', the fractional division operator +`//', the logical not operator `!' and the modulus operator `%' are not +available. + + Symbols are not global by default, unless the option +`--globalize-symbols' is passed. Use the `.global' directive to +globalize symbols (*note Global::). + + Operand syntax is a bit stricter with `as' than `mmixal'. For +example, you can't say `addu 1,2,3', instead you must write `addu +$1,$2,3'. + + You can't LOC to a lower address than those already visited (i.e., +"backwards"). + + A LOC directive must come before any emitted code. + + Predefined symbols are visible as file-local symbols after use. (In +the ELF file, that is--the linked mmo file has no notion of a file-local +symbol.) + + Some mapping of constant expressions to sections in LOC expressions +is attempted, but that functionality is easily confused and should be +avoided unless compatibility with `mmixal' is required. A LOC +expression to `0x2000000000000000' or higher, maps to the `.data' +section and lower addresses map to the `.text' section (*note +MMIX-loc::). + + The code and data areas are each contiguous. Sparse programs with +far-away LOC directives will take up the same amount of space as a +contiguous program with zeros filled in the gaps between the LOC +directives. If you need sparse programs, you might try and get the +wanted effect with a linker script and splitting up the code parts into +sections (*note Section::). Assembly code for this, to be compatible +with `mmixal', would look something like: + .if 0 + LOC away_expression + .else + .section away,"ax" + .fi + `as' will not execute the LOC directive and `mmixal' ignores the +lines with `.'. This construct can be used generally to help +compatibility. + + Symbols can't be defined twice-not even to the same value. + + Instruction mnemonics are recognized case-insensitive, though the +`IS' and `GREG' pseudo-operations must be specified in upper-case +characters. + + There's no unicode support. + + The following is a list of programs in `mmix.tar.gz', available at +`http://www-cs-faculty.stanford.edu/~knuth/mmix-news.html', last +checked with the version dated 2001-08-25 (md5sum +c393470cfc86fac040487d22d2bf0172) that assemble with `mmixal' but do +not assemble with `as': + +`silly.mms' + LOC to a previous address. + +`sim.mms' + Redefines symbol `Done'. + +`test.mms' + Uses the serial operator `&'. + + +File: as.info, Node: MSP430-Dependent, Next: SH-Dependent, Prev: MMIX-Dependent, Up: Machine Dependencies + +9.26 MSP 430 Dependent Features +=============================== + +* Menu: + +* MSP430 Options:: Options +* MSP430 Syntax:: Syntax +* MSP430 Floating Point:: Floating Point +* MSP430 Directives:: MSP 430 Machine Directives +* MSP430 Opcodes:: Opcodes +* MSP430 Profiling Capability:: Profiling Capability + + +File: as.info, Node: MSP430 Options, Next: MSP430 Syntax, Up: MSP430-Dependent + +9.26.1 Options +-------------- + +`-m' + select the mpu arch. Currently has no effect. + +`-mP' + enables polymorph instructions handler. + +`-mQ' + enables relaxation at assembly time. DANGEROUS! + + + +File: as.info, Node: MSP430 Syntax, Next: MSP430 Floating Point, Prev: MSP430 Options, Up: MSP430-Dependent + +9.26.2 Syntax +------------- + +* Menu: + +* MSP430-Macros:: Macros +* MSP430-Chars:: Special Characters +* MSP430-Regs:: Register Names +* MSP430-Ext:: Assembler Extensions + + +File: as.info, Node: MSP430-Macros, Next: MSP430-Chars, Up: MSP430 Syntax + +9.26.2.1 Macros +............... + +The macro syntax used on the MSP 430 is like that described in the MSP +430 Family Assembler Specification. Normal `as' macros should still +work. + + Additional built-in macros are: + +`llo(exp)' + Extracts least significant word from 32-bit expression 'exp'. + +`lhi(exp)' + Extracts most significant word from 32-bit expression 'exp'. + +`hlo(exp)' + Extracts 3rd word from 64-bit expression 'exp'. + +`hhi(exp)' + Extracts 4rd word from 64-bit expression 'exp'. + + + They normally being used as an immediate source operand. + mov #llo(1), r10 ; == mov #1, r10 + mov #lhi(1), r10 ; == mov #0, r10 + + +File: as.info, Node: MSP430-Chars, Next: MSP430-Regs, Prev: MSP430-Macros, Up: MSP430 Syntax + +9.26.2.2 Special Characters +........................... + +`;' is the line comment character. + + The character `$' in jump instructions indicates current location and +implemented only for TI syntax compatibility. + + +File: as.info, Node: MSP430-Regs, Next: MSP430-Ext, Prev: MSP430-Chars, Up: MSP430 Syntax + +9.26.2.3 Register Names +....................... + +General-purpose registers are represented by predefined symbols of the +form `rN' (for global registers), where N represents a number between +`0' and `15'. The leading letters may be in either upper or lower +case; for example, `r13' and `R7' are both valid register names. + + Register names `PC', `SP' and `SR' cannot be used as register names +and will be treated as variables. Use `r0', `r1', and `r2' instead. + + +File: as.info, Node: MSP430-Ext, Prev: MSP430-Regs, Up: MSP430 Syntax + +9.26.2.4 Assembler Extensions +............................. + +`@rN' + As destination operand being treated as `0(rn)' + +`0(rN)' + As source operand being treated as `@rn' + +`jCOND +N' + Skips next N bytes followed by jump instruction and equivalent to + `jCOND $+N+2' + + + Also, there are some instructions, which cannot be found in other +assemblers. These are branch instructions, which has different opcodes +upon jump distance. They all got PC relative addressing mode. + +`beq label' + A polymorph instruction which is `jeq label' in case if jump + distance within allowed range for cpu's jump instruction. If not, + this unrolls into a sequence of + jne $+6 + br label + +`bne label' + A polymorph instruction which is `jne label' or `jeq +4; br label' + +`blt label' + A polymorph instruction which is `jl label' or `jge +4; br label' + +`bltn label' + A polymorph instruction which is `jn label' or `jn +2; jmp +4; br + label' + +`bltu label' + A polymorph instruction which is `jlo label' or `jhs +2; br label' + +`bge label' + A polymorph instruction which is `jge label' or `jl +4; br label' + +`bgeu label' + A polymorph instruction which is `jhs label' or `jlo +4; br label' + +`bgt label' + A polymorph instruction which is `jeq +2; jge label' or `jeq +6; + jl +4; br label' + +`bgtu label' + A polymorph instruction which is `jeq +2; jhs label' or `jeq +6; + jlo +4; br label' + +`bleu label' + A polymorph instruction which is `jeq label; jlo label' or `jeq + +2; jhs +4; br label' + +`ble label' + A polymorph instruction which is `jeq label; jl label' or `jeq + +2; jge +4; br label' + +`jump label' + A polymorph instruction which is `jmp label' or `br label' + + +File: as.info, Node: MSP430 Floating Point, Next: MSP430 Directives, Prev: MSP430 Syntax, Up: MSP430-Dependent + +9.26.3 Floating Point +--------------------- + +The MSP 430 family uses IEEE 32-bit floating-point numbers. + + +File: as.info, Node: MSP430 Directives, Next: MSP430 Opcodes, Prev: MSP430 Floating Point, Up: MSP430-Dependent + +9.26.4 MSP 430 Machine Directives +--------------------------------- + +`.file' + This directive is ignored; it is accepted for compatibility with + other MSP 430 assemblers. + + _Warning:_ in other versions of the GNU assembler, `.file' is + used for the directive called `.app-file' in the MSP 430 + support. + +`.line' + This directive is ignored; it is accepted for compatibility with + other MSP 430 assemblers. + +`.arch' + Currently this directive is ignored; it is accepted for + compatibility with other MSP 430 assemblers. + +`.profiler' + This directive instructs assembler to add new profile entry to the + object file. + + + +File: as.info, Node: MSP430 Opcodes, Next: MSP430 Profiling Capability, Prev: MSP430 Directives, Up: MSP430-Dependent + +9.26.5 Opcodes +-------------- + +`as' implements all the standard MSP 430 opcodes. No additional +pseudo-instructions are needed on this family. + + For information on the 430 machine instruction set, see `MSP430 +User's Manual, document slau049d', Texas Instrument, Inc. + + +File: as.info, Node: MSP430 Profiling Capability, Prev: MSP430 Opcodes, Up: MSP430-Dependent + +9.26.6 Profiling Capability +--------------------------- + +It is a performance hit to use gcc's profiling approach for this tiny +target. Even more - jtag hardware facility does not perform any +profiling functions. However we've got gdb's built-in simulator where +we can do anything. + + We define new section `.profiler' which holds all profiling +information. We define new pseudo operation `.profiler' which will +instruct assembler to add new profile entry to the object file. Profile +should take place at the present address. + + Pseudo operation format: + + `.profiler flags,function_to_profile [, cycle_corrector, extra]' + + where: + + `flags' is a combination of the following characters: + + `s' + function entry + + `x' + function exit + + `i' + function is in init section + + `f' + function is in fini section + + `l' + library call + + `c' + libc standard call + + `d' + stack value demand + + `I' + interrupt service routine + + `P' + prologue start + + `p' + prologue end + + `E' + epilogue start + + `e' + epilogue end + + `j' + long jump / sjlj unwind + + `a' + an arbitrary code fragment + + `t' + extra parameter saved (a constant value like frame size) + +`function_to_profile' + a function address + +`cycle_corrector' + a value which should be added to the cycle counter, zero if + omitted. + +`extra' + any extra parameter, zero if omitted. + + + For example: + .global fxx + .type fxx,@function + fxx: + .LFrameOffset_fxx=0x08 + .profiler "scdP", fxx ; function entry. + ; we also demand stack value to be saved + push r11 + push r10 + push r9 + push r8 + .profiler "cdpt",fxx,0, .LFrameOffset_fxx ; check stack value at this point + ; (this is a prologue end) + ; note, that spare var filled with + ; the farme size + mov r15,r8 + ... + .profiler cdE,fxx ; check stack + pop r8 + pop r9 + pop r10 + pop r11 + .profiler xcde,fxx,3 ; exit adds 3 to the cycle counter + ret ; cause 'ret' insn takes 3 cycles + + +File: as.info, Node: PDP-11-Dependent, Next: PJ-Dependent, Prev: SH64-Dependent, Up: Machine Dependencies + +9.27 PDP-11 Dependent Features +============================== + +* Menu: + +* PDP-11-Options:: Options +* PDP-11-Pseudos:: Assembler Directives +* PDP-11-Syntax:: DEC Syntax versus BSD Syntax +* PDP-11-Mnemonics:: Instruction Naming +* PDP-11-Synthetic:: Synthetic Instructions + + +File: as.info, Node: PDP-11-Options, Next: PDP-11-Pseudos, Up: PDP-11-Dependent + +9.27.1 Options +-------------- + +The PDP-11 version of `as' has a rich set of machine dependent options. + +9.27.1.1 Code Generation Options +................................ + +`-mpic | -mno-pic' + Generate position-independent (or position-dependent) code. + + The default is to generate position-independent code. + +9.27.1.2 Instruction Set Extension Options +.......................................... + +These options enables or disables the use of extensions over the base +line instruction set as introduced by the first PDP-11 CPU: the KA11. +Most options come in two variants: a `-m'EXTENSION that enables +EXTENSION, and a `-mno-'EXTENSION that disables EXTENSION. + + The default is to enable all extensions. + +`-mall | -mall-extensions' + Enable all instruction set extensions. + +`-mno-extensions' + Disable all instruction set extensions. + +`-mcis | -mno-cis' + Enable (or disable) the use of the commercial instruction set, + which consists of these instructions: `ADDNI', `ADDN', `ADDPI', + `ADDP', `ASHNI', `ASHN', `ASHPI', `ASHP', `CMPCI', `CMPC', + `CMPNI', `CMPN', `CMPPI', `CMPP', `CVTLNI', `CVTLN', `CVTLPI', + `CVTLP', `CVTNLI', `CVTNL', `CVTNPI', `CVTNP', `CVTPLI', `CVTPL', + `CVTPNI', `CVTPN', `DIVPI', `DIVP', `L2DR', `L3DR', `LOCCI', + `LOCC', `MATCI', `MATC', `MOVCI', `MOVC', `MOVRCI', `MOVRC', + `MOVTCI', `MOVTC', `MULPI', `MULP', `SCANCI', `SCANC', `SKPCI', + `SKPC', `SPANCI', `SPANC', `SUBNI', `SUBN', `SUBPI', and `SUBP'. + +`-mcsm | -mno-csm' + Enable (or disable) the use of the `CSM' instruction. + +`-meis | -mno-eis' + Enable (or disable) the use of the extended instruction set, which + consists of these instructions: `ASHC', `ASH', `DIV', `MARK', + `MUL', `RTT', `SOB' `SXT', and `XOR'. + +`-mfis | -mkev11' +`-mno-fis | -mno-kev11' + Enable (or disable) the use of the KEV11 floating-point + instructions: `FADD', `FDIV', `FMUL', and `FSUB'. + +`-mfpp | -mfpu | -mfp-11' +`-mno-fpp | -mno-fpu | -mno-fp-11' + Enable (or disable) the use of FP-11 floating-point instructions: + `ABSF', `ADDF', `CFCC', `CLRF', `CMPF', `DIVF', `LDCFF', `LDCIF', + `LDEXP', `LDF', `LDFPS', `MODF', `MULF', `NEGF', `SETD', `SETF', + `SETI', `SETL', `STCFF', `STCFI', `STEXP', `STF', `STFPS', `STST', + `SUBF', and `TSTF'. + +`-mlimited-eis | -mno-limited-eis' + Enable (or disable) the use of the limited extended instruction + set: `MARK', `RTT', `SOB', `SXT', and `XOR'. + + The -mno-limited-eis options also implies -mno-eis. + +`-mmfpt | -mno-mfpt' + Enable (or disable) the use of the `MFPT' instruction. + +`-mmultiproc | -mno-multiproc' + Enable (or disable) the use of multiprocessor instructions: + `TSTSET' and `WRTLCK'. + +`-mmxps | -mno-mxps' + Enable (or disable) the use of the `MFPS' and `MTPS' instructions. + +`-mspl | -mno-spl' + Enable (or disable) the use of the `SPL' instruction. + + Enable (or disable) the use of the microcode instructions: `LDUB', + `MED', and `XFC'. + +9.27.1.3 CPU Model Options +.......................... + +These options enable the instruction set extensions supported by a +particular CPU, and disables all other extensions. + +`-mka11' + KA11 CPU. Base line instruction set only. + +`-mkb11' + KB11 CPU. Enable extended instruction set and `SPL'. + +`-mkd11a' + KD11-A CPU. Enable limited extended instruction set. + +`-mkd11b' + KD11-B CPU. Base line instruction set only. + +`-mkd11d' + KD11-D CPU. Base line instruction set only. + +`-mkd11e' + KD11-E CPU. Enable extended instruction set, `MFPS', and `MTPS'. + +`-mkd11f | -mkd11h | -mkd11q' + KD11-F, KD11-H, or KD11-Q CPU. Enable limited extended + instruction set, `MFPS', and `MTPS'. + +`-mkd11k' + KD11-K CPU. Enable extended instruction set, `LDUB', `MED', + `MFPS', `MFPT', `MTPS', and `XFC'. + +`-mkd11z' + KD11-Z CPU. Enable extended instruction set, `CSM', `MFPS', + `MFPT', `MTPS', and `SPL'. + +`-mf11' + F11 CPU. Enable extended instruction set, `MFPS', `MFPT', and + `MTPS'. + +`-mj11' + J11 CPU. Enable extended instruction set, `CSM', `MFPS', `MFPT', + `MTPS', `SPL', `TSTSET', and `WRTLCK'. + +`-mt11' + T11 CPU. Enable limited extended instruction set, `MFPS', and + `MTPS'. + +9.27.1.4 Machine Model Options +.............................. + +These options enable the instruction set extensions supported by a +particular machine model, and disables all other extensions. + +`-m11/03' + Same as `-mkd11f'. + +`-m11/04' + Same as `-mkd11d'. + +`-m11/05 | -m11/10' + Same as `-mkd11b'. + +`-m11/15 | -m11/20' + Same as `-mka11'. + +`-m11/21' + Same as `-mt11'. + +`-m11/23 | -m11/24' + Same as `-mf11'. + +`-m11/34' + Same as `-mkd11e'. + +`-m11/34a' + Ame as `-mkd11e' `-mfpp'. + +`-m11/35 | -m11/40' + Same as `-mkd11a'. + +`-m11/44' + Same as `-mkd11z'. + +`-m11/45 | -m11/50 | -m11/55 | -m11/70' + Same as `-mkb11'. + +`-m11/53 | -m11/73 | -m11/83 | -m11/84 | -m11/93 | -m11/94' + Same as `-mj11'. + +`-m11/60' + Same as `-mkd11k'. + + +File: as.info, Node: PDP-11-Pseudos, Next: PDP-11-Syntax, Prev: PDP-11-Options, Up: PDP-11-Dependent + +9.27.2 Assembler Directives +--------------------------- + +The PDP-11 version of `as' has a few machine dependent assembler +directives. + +`.bss' + Switch to the `bss' section. + +`.even' + Align the location counter to an even number. + + +File: as.info, Node: PDP-11-Syntax, Next: PDP-11-Mnemonics, Prev: PDP-11-Pseudos, Up: PDP-11-Dependent + +9.27.3 PDP-11 Assembly Language Syntax +-------------------------------------- + +`as' supports both DEC syntax and BSD syntax. The only difference is +that in DEC syntax, a `#' character is used to denote an immediate +constants, while in BSD syntax the character for this purpose is `$'. + + general-purpose registers are named `r0' through `r7'. Mnemonic +alternatives for `r6' and `r7' are `sp' and `pc', respectively. + + Floating-point registers are named `ac0' through `ac3', or +alternatively `fr0' through `fr3'. + + Comments are started with a `#' or a `/' character, and extend to +the end of the line. (FIXME: clash with immediates?) + + +File: as.info, Node: PDP-11-Mnemonics, Next: PDP-11-Synthetic, Prev: PDP-11-Syntax, Up: PDP-11-Dependent + +9.27.4 Instruction Naming +------------------------- + +Some instructions have alternative names. + +`BCC' + `BHIS' + +`BCS' + `BLO' + +`L2DR' + `L2D' + +`L3DR' + `L3D' + +`SYS' + `TRAP' + + +File: as.info, Node: PDP-11-Synthetic, Prev: PDP-11-Mnemonics, Up: PDP-11-Dependent + +9.27.5 Synthetic Instructions +----------------------------- + +The `JBR' and `J'CC synthetic instructions are not supported yet. + + +File: as.info, Node: PJ-Dependent, Next: PPC-Dependent, Prev: PDP-11-Dependent, Up: Machine Dependencies + +9.28 picoJava Dependent Features +================================ + +* Menu: + +* PJ Options:: Options + + +File: as.info, Node: PJ Options, Up: PJ-Dependent + +9.28.1 Options +-------------- + +`as' has two additional command-line options for the picoJava +architecture. +`-ml' + This option selects little endian data output. + +`-mb' + This option selects big endian data output. + + +File: as.info, Node: PPC-Dependent, Next: S/390-Dependent, Prev: PJ-Dependent, Up: Machine Dependencies + +9.29 PowerPC Dependent Features +=============================== + +* Menu: + +* PowerPC-Opts:: Options +* PowerPC-Pseudo:: PowerPC Assembler Directives + + +File: as.info, Node: PowerPC-Opts, Next: PowerPC-Pseudo, Up: PPC-Dependent + +9.29.1 Options +-------------- + +The PowerPC chip family includes several successive levels, using the +same core instruction set, but including a few additional instructions +at each level. There are exceptions to this however. For details on +what instructions each variant supports, please see the chip's +architecture reference manual. + + The following table lists all available PowerPC options. + +`-mpwrx | -mpwr2' + Generate code for POWER/2 (RIOS2). + +`-mpwr' + Generate code for POWER (RIOS1) + +`-m601' + Generate code for PowerPC 601. + +`-mppc, -mppc32, -m603, -m604' + Generate code for PowerPC 603/604. + +`-m403, -m405' + Generate code for PowerPC 403/405. + +`-m440' + Generate code for PowerPC 440. BookE and some 405 instructions. + +`-m476' + Generate code for PowerPC 476. + +`-m7400, -m7410, -m7450, -m7455' + Generate code for PowerPC 7400/7410/7450/7455. + +`-m750cl' + Generate code for PowerPC 750CL. + +`-mppc64, -m620' + Generate code for PowerPC 620/625/630. + +`-me500, -me500x2' + Generate code for Motorola e500 core complex. + +`-mspe' + Generate code for Motorola SPE instructions. + +`-mppc64bridge' + Generate code for PowerPC 64, including bridge insns. + +`-mbooke' + Generate code for 32-bit BookE. + +`-ma2' + Generate code for A2 architecture. + +`-me300' + Generate code for PowerPC e300 family. + +`-maltivec' + Generate code for processors with AltiVec instructions. + +`-mvsx' + Generate code for processors with Vector-Scalar (VSX) instructions. + +`-mpower4' + Generate code for Power4 architecture. + +`-mpower5' + Generate code for Power5 architecture. + +`-mpower6' + Generate code for Power6 architecture. + +`-mpower7' + Generate code for Power7 architecture. + +`-mcell' + Generate code for Cell Broadband Engine architecture. + +`-mcom' + Generate code Power/PowerPC common instructions. + +`-many' + Generate code for any architecture (PWR/PWRX/PPC). + +`-mregnames' + Allow symbolic names for registers. + +`-mno-regnames' + Do not allow symbolic names for registers. + +`-mrelocatable' + Support for GCC's -mrelocatable option. + +`-mrelocatable-lib' + Support for GCC's -mrelocatable-lib option. + +`-memb' + Set PPC_EMB bit in ELF flags. + +`-mlittle, -mlittle-endian' + Generate code for a little endian machine. + +`-mbig, -mbig-endian' + Generate code for a big endian machine. + +`-msolaris' + Generate code for Solaris. + +`-mno-solaris' + Do not generate code for Solaris. + + +File: as.info, Node: PowerPC-Pseudo, Prev: PowerPC-Opts, Up: PPC-Dependent + +9.29.2 PowerPC Assembler Directives +----------------------------------- + +A number of assembler directives are available for PowerPC. The +following table is far from complete. + +`.machine "string"' + This directive allows you to change the machine for which code is + generated. `"string"' may be any of the -m cpu selection options + (without the -m) enclosed in double quotes, `"push"', or `"pop"'. + `.machine "push"' saves the currently selected cpu, which may be + restored with `.machine "pop"'. + + +File: as.info, Node: S/390-Dependent, Next: SCORE-Dependent, Prev: PPC-Dependent, Up: Machine Dependencies + +9.30 IBM S/390 Dependent Features +================================= + + The s390 version of `as' supports two architectures modes and seven +chip levels. The architecture modes are the Enterprise System +Architecture (ESA) and the newer z/Architecture mode. The chip levels +are g5, g6, z900, z990, z9-109, z9-ec and z10. + +* Menu: + +* s390 Options:: Command-line Options. +* s390 Characters:: Special Characters. +* s390 Syntax:: Assembler Instruction syntax. +* s390 Directives:: Assembler Directives. +* s390 Floating Point:: Floating Point. + + +File: as.info, Node: s390 Options, Next: s390 Characters, Up: S/390-Dependent + +9.30.1 Options +-------------- + +The following table lists all available s390 specific options: + +`-m31 | -m64' + Select 31- or 64-bit ABI implying a word size of 32- or 64-bit. + + These options are only available with the ELF object file format, + and require that the necessary BFD support has been included (on a + 31-bit platform you must add -enable-64-bit-bfd on the call to the + configure script to enable 64-bit usage and use s390x as target + platform). + +`-mesa | -mzarch' + Select the architecture mode, either the Enterprise System + Architecture (esa) mode or the z/Architecture mode (zarch). + + The 64-bit instructions are only available with the z/Architecture + mode. The combination of `-m64' and `-mesa' results in a warning + message. + +`-march=CPU' + This option specifies the target processor. The following + processor names are recognized: `g5', `g6', `z900', `z990', + `z9-109', `z9-ec' and `z10'. Assembling an instruction that is + not supported on the target processor results in an error message. + Do not specify `g5' or `g6' with `-mzarch'. + +`-mregnames' + Allow symbolic names for registers. + +`-mno-regnames' + Do not allow symbolic names for registers. + +`-mwarn-areg-zero' + Warn whenever the operand for a base or index register has been + specified but evaluates to zero. This can indicate the misuse of + general purpose register 0 as an address register. + + + +File: as.info, Node: s390 Characters, Next: s390 Syntax, Prev: s390 Options, Up: S/390-Dependent + +9.30.2 Special Characters +------------------------- + +`#' is the line comment character. + + +File: as.info, Node: s390 Syntax, Next: s390 Directives, Prev: s390 Characters, Up: S/390-Dependent + +9.30.3 Instruction syntax +------------------------- + +The assembler syntax closely follows the syntax outlined in Enterprise +Systems Architecture/390 Principles of Operation (SA22-7201) and the +z/Architecture Principles of Operation (SA22-7832). + + Each instruction has two major parts, the instruction mnemonic and +the instruction operands. The instruction format varies. + +* Menu: + +* s390 Register:: Register Naming +* s390 Mnemonics:: Instruction Mnemonics +* s390 Operands:: Instruction Operands +* s390 Formats:: Instruction Formats +* s390 Aliases:: Instruction Aliases +* s390 Operand Modifier:: Instruction Operand Modifier +* s390 Instruction Marker:: Instruction Marker +* s390 Literal Pool Entries:: Literal Pool Entries + + +File: as.info, Node: s390 Register, Next: s390 Mnemonics, Up: s390 Syntax + +9.30.3.1 Register naming +........................ + +The `as' recognizes a number of predefined symbols for the various +processor registers. A register specification in one of the instruction +formats is an unsigned integer between 0 and 15. The specific +instruction and the position of the register in the instruction format +denotes the type of the register. The register symbols are prefixed with +`%': + + %rN the 16 general purpose registers, 0 <= N <= 15 + %fN the 16 floating point registers, 0 <= N <= 15 + %aN the 16 access registers, 0 <= N <= 15 + %cN the 16 control registers, 0 <= N <= 15 + %lit an alias for the general purpose register %r13 + %sp an alias for the general purpose register %r15 + + +File: as.info, Node: s390 Mnemonics, Next: s390 Operands, Prev: s390 Register, Up: s390 Syntax + +9.30.3.2 Instruction Mnemonics +.............................. + +All instructions documented in the Principles of Operation are supported +with the mnemonic and order of operands as described. The instruction +mnemonic identifies the instruction format (*Note s390 Formats::) and +the specific operation code for the instruction. For example, the `lr' +mnemonic denotes the instruction format `RR' with the operation code +`0x18'. + + The definition of the various mnemonics follows a scheme, where the +first character usually hint at the type of the instruction: + + a add instruction, for example `al' for add logical 32-bit + b branch instruction, for example `bc' for branch on condition + c compare or convert instruction, for example `cr' for compare + register 32-bit + d divide instruction, for example `dlr' devide logical register + 64-bit to 32-bit + i insert instruction, for example `ic' insert character + l load instruction, for example `ltr' load and test register + mv move instruction, for example `mvc' move character + m multiply instruction, for example `mh' multiply halfword + n and instruction, for example `ni' and immediate + o or instruction, for example `oc' or character + sla, sll shift left single instruction + sra, srl shift right single instruction + st store instruction, for example `stm' store multiple + s subtract instruction, for example `slr' subtract + logical 32-bit + t test or translate instruction, of example `tm' test under mask + x exclusive or instruction, for example `xc' exclusive or + character + + Certain characters at the end of the mnemonic may describe a property +of the instruction: + + c the instruction uses a 8-bit character operand + f the instruction extends a 32-bit operand to 64 bit + g the operands are treated as 64-bit values + h the operand uses a 16-bit halfword operand + i the instruction uses an immediate operand + l the instruction uses unsigned, logical operands + m the instruction uses a mask or operates on multiple values + r if r is the last character, the instruction operates on registers + y the instruction uses 20-bit displacements + + There are many exceptions to the scheme outlined in the above lists, +in particular for the priviledged instructions. For non-priviledged +instruction it works quite well, for example the instruction `clgfr' c: +compare instruction, l: unsigned operands, g: 64-bit operands, f: 32- +to 64-bit extension, r: register operands. The instruction compares an +64-bit value in a register with the zero extended 32-bit value from a +second register. For a complete list of all mnemonics see appendix B +in the Principles of Operation. + + +File: as.info, Node: s390 Operands, Next: s390 Formats, Prev: s390 Mnemonics, Up: s390 Syntax + +9.30.3.3 Instruction Operands +............................. + +Instruction operands can be grouped into three classes, operands located +in registers, immediate operands, and operands in storage. + + A register operand can be located in general, floating-point, access, +or control register. The register is identified by a four-bit field. +The field containing the register operand is called the R field. + + Immediate operands are contained within the instruction and can have +8, 16 or 32 bits. The field containing the immediate operand is called +the I field. Dependent on the instruction the I field is either signed +or unsigned. + + A storage operand consists of an address and a length. The address +of a storage operands can be specified in any of these ways: + + * The content of a single general R + + * The sum of the content of a general register called the base + register B plus the content of a displacement field D + + * The sum of the contents of two general registers called the index + register X and the base register B plus the content of a + displacement field + + * The sum of the current instruction address and a 32-bit signed + immediate field multiplied by two. + + The length of a storage operand can be: + + * Implied by the instruction + + * Specified by a bitmask + + * Specified by a four-bit or eight-bit length field L + + * Specified by the content of a general register + + The notation for storage operand addresses formed from multiple +fields is as follows: + +`Dn(Bn)' + the address for operand number n is formed from the content of + general register Bn called the base register and the displacement + field Dn. + +`Dn(Xn,Bn)' + the address for operand number n is formed from the content of + general register Xn called the index register, general register Bn + called the base register and the displacement field Dn. + +`Dn(Ln,Bn)' + the address for operand number n is formed from the content of + general regiser Bn called the base register and the displacement + field Dn. The length of the operand n is specified by the field + Ln. + + The base registers Bn and the index registers Xn of a storage +operand can be skipped. If Bn and Xn are skipped, a zero will be stored +to the operand field. The notation changes as follows: + + full notation short notation + ------------------------------------------ + Dn(0,Bn) Dn(Bn) + Dn(0,0) Dn + Dn(0) Dn + Dn(Ln,0) Dn(Ln) + + +File: as.info, Node: s390 Formats, Next: s390 Aliases, Prev: s390 Operands, Up: s390 Syntax + +9.30.3.4 Instruction Formats +............................ + +The Principles of Operation manuals lists 26 instruction formats where +some of the formats have multiple variants. For the `.insn' pseudo +directive the assembler recognizes some of the formats. Typically, the +most general variant of the instruction format is used by the `.insn' +directive. + + The following table lists the abbreviations used in the table of +instruction formats: + + OpCode / OpCd Part of the op code. + Bx Base register number for operand x. + Dx Displacement for operand x. + DLx Displacement lower 12 bits for operand x. + DHx Displacement higher 8-bits for operand x. + Rx Register number for operand x. + Xx Index register number for operand x. + Ix Signed immediate for operand x. + Ux Unsigned immediate for operand x. + + An instruction is two, four, or six bytes in length and must be +aligned on a 2 byte boundary. The first two bits of the instruction +specify the length of the instruction, 00 indicates a two byte +instruction, 01 and 10 indicates a four byte instruction, and 11 +indicates a six byte instruction. + + The following table lists the s390 instruction formats that are +available with the `.insn' pseudo directive: + +`E format' + + +-------------+ + | OpCode | + +-------------+ + 0 15 + +`RI format: <insn> R1,I2' + + +--------+----+----+------------------+ + | OpCode | R1 |OpCd| I2 | + +--------+----+----+------------------+ + 0 8 12 16 31 + +`RIE format: <insn> R1,R3,I2' + + +--------+----+----+------------------+--------+--------+ + | OpCode | R1 | R3 | I2 |////////| OpCode | + +--------+----+----+------------------+--------+--------+ + 0 8 12 16 32 40 47 + +`RIL format: <insn> R1,I2' + + +--------+----+----+------------------------------------+ + | OpCode | R1 |OpCd| I2 | + +--------+----+----+------------------------------------+ + 0 8 12 16 47 + +`RILU format: <insn> R1,U2' + + +--------+----+----+------------------------------------+ + | OpCode | R1 |OpCd| U2 | + +--------+----+----+------------------------------------+ + 0 8 12 16 47 + +`RIS format: <insn> R1,I2,M3,D4(B4)' + + +--------+----+----+----+-------------+--------+--------+ + | OpCode | R1 | M3 | B4 | D4 | I2 | Opcode | + +--------+----+----+----+-------------+--------+--------+ + 0 8 12 16 20 32 36 47 + +`RR format: <insn> R1,R2' + + +--------+----+----+ + | OpCode | R1 | R2 | + +--------+----+----+ + 0 8 12 15 + +`RRE format: <insn> R1,R2' + + +------------------+--------+----+----+ + | OpCode |////////| R1 | R2 | + +------------------+--------+----+----+ + 0 16 24 28 31 + +`RRF format: <insn> R1,R2,R3,M4' + + +------------------+----+----+----+----+ + | OpCode | R3 | M4 | R1 | R2 | + +------------------+----+----+----+----+ + 0 16 20 24 28 31 + +`RRS format: <insn> R1,R2,M3,D4(B4)' + + +--------+----+----+----+-------------+----+----+--------+ + | OpCode | R1 | R3 | B4 | D4 | M3 |////| OpCode | + +--------+----+----+----+-------------+----+----+--------+ + 0 8 12 16 20 32 36 40 47 + +`RS format: <insn> R1,R3,D2(B2)' + + +--------+----+----+----+-------------+ + | OpCode | R1 | R3 | B2 | D2 | + +--------+----+----+----+-------------+ + 0 8 12 16 20 31 + +`RSE format: <insn> R1,R3,D2(B2)' + + +--------+----+----+----+-------------+--------+--------+ + | OpCode | R1 | R3 | B2 | D2 |////////| OpCode | + +--------+----+----+----+-------------+--------+--------+ + 0 8 12 16 20 32 40 47 + +`RSI format: <insn> R1,R3,I2' + + +--------+----+----+------------------------------------+ + | OpCode | R1 | R3 | I2 | + +--------+----+----+------------------------------------+ + 0 8 12 16 47 + +`RSY format: <insn> R1,R3,D2(B2)' + + +--------+----+----+----+-------------+--------+--------+ + | OpCode | R1 | R3 | B2 | DL2 | DH2 | OpCode | + +--------+----+----+----+-------------+--------+--------+ + 0 8 12 16 20 32 40 47 + +`RX format: <insn> R1,D2(X2,B2)' + + +--------+----+----+----+-------------+ + | OpCode | R1 | X2 | B2 | D2 | + +--------+----+----+----+-------------+ + 0 8 12 16 20 31 + +`RXE format: <insn> R1,D2(X2,B2)' + + +--------+----+----+----+-------------+--------+--------+ + | OpCode | R1 | X2 | B2 | D2 |////////| OpCode | + +--------+----+----+----+-------------+--------+--------+ + 0 8 12 16 20 32 40 47 + +`RXF format: <insn> R1,R3,D2(X2,B2)' + + +--------+----+----+----+-------------+----+---+--------+ + | OpCode | R3 | X2 | B2 | D2 | R1 |///| OpCode | + +--------+----+----+----+-------------+----+---+--------+ + 0 8 12 16 20 32 36 40 47 + +`RXY format: <insn> R1,D2(X2,B2)' + + +--------+----+----+----+-------------+--------+--------+ + | OpCode | R1 | X2 | B2 | DL2 | DH2 | OpCode | + +--------+----+----+----+-------------+--------+--------+ + 0 8 12 16 20 32 36 40 47 + +`S format: <insn> D2(B2)' + + +------------------+----+-------------+ + | OpCode | B2 | D2 | + +------------------+----+-------------+ + 0 16 20 31 + +`SI format: <insn> D1(B1),I2' + + +--------+---------+----+-------------+ + | OpCode | I2 | B1 | D1 | + +--------+---------+----+-------------+ + 0 8 16 20 31 + +`SIY format: <insn> D1(B1),U2' + + +--------+---------+----+-------------+--------+--------+ + | OpCode | I2 | B1 | DL1 | DH1 | OpCode | + +--------+---------+----+-------------+--------+--------+ + 0 8 16 20 32 36 40 47 + +`SIL format: <insn> D1(B1),I2' + + +------------------+----+-------------+-----------------+ + | OpCode | B1 | D1 | I2 | + +------------------+----+-------------+-----------------+ + 0 16 20 32 47 + +`SS format: <insn> D1(R1,B1),D2(B3),R3' + + +--------+----+----+----+-------------+----+------------+ + | OpCode | R1 | R3 | B1 | D1 | B2 | D2 | + +--------+----+----+----+-------------+----+------------+ + 0 8 12 16 20 32 36 47 + +`SSE format: <insn> D1(B1),D2(B2)' + + +------------------+----+-------------+----+------------+ + | OpCode | B1 | D1 | B2 | D2 | + +------------------+----+-------------+----+------------+ + 0 8 12 16 20 32 36 47 + +`SSF format: <insn> D1(B1),D2(B2),R3' + + +--------+----+----+----+-------------+----+------------+ + | OpCode | R3 |OpCd| B1 | D1 | B2 | D2 | + +--------+----+----+----+-------------+----+------------+ + 0 8 12 16 20 32 36 47 + + + For the complete list of all instruction format variants see the +Principles of Operation manuals. + + +File: as.info, Node: s390 Aliases, Next: s390 Operand Modifier, Prev: s390 Formats, Up: s390 Syntax + +9.30.3.5 Instruction Aliases +............................ + +A specific bit pattern can have multiple mnemonics, for example the bit +pattern `0xa7000000' has the mnemonics `tmh' and `tmlh'. In addition, +there are a number of mnemonics recognized by `as' that are not present +in the Principles of Operation. These are the short forms of the +branch instructions, where the condition code mask operand is encoded +in the mnemonic. This is relevant for the branch instructions, the +compare and branch instructions, and the compare and trap instructions. + + For the branch instructions there are 20 condition code strings that +can be used as part of the mnemonic in place of a mask operand in the +instruction format: + + instruction short form + ------------------------------------------ + bcr M1,R2 b<m>r R2 + bc M1,D2(X2,B2) b<m> D2(X2,B2) + brc M1,I2 j<m> I2 + brcl M1,I2 jg<m> I2 + + In the mnemonic for a branch instruction the condition code string +<m> can be any of the following: + + o jump on overflow / if ones + h jump on A high + p jump on plus + nle jump on not low or equal + l jump on A low + m jump on minus + nhe jump on not high or equal + lh jump on low or high + ne jump on A not equal B + nz jump on not zero / if not zeros + e jump on A equal B + z jump on zero / if zeroes + nlh jump on not low or high + he jump on high or equal + nl jump on A not low + nm jump on not minus / if not mixed + le jump on low or equal + nh jump on A not high + np jump on not plus + no jump on not overflow / if not ones + + For the compare and branch, and compare and trap instructions there +are 12 condition code strings that can be used as part of the mnemonic +in place of a mask operand in the instruction format: + + instruction short form + -------------------------------------------------------- + crb R1,R2,M3,D4(B4) crb<m> R1,R2,D4(B4) + cgrb R1,R2,M3,D4(B4) cgrb<m> R1,R2,D4(B4) + crj R1,R2,M3,I4 crj<m> R1,R2,I4 + cgrj R1,R2,M3,I4 cgrj<m> R1,R2,I4 + cib R1,I2,M3,D4(B4) cib<m> R1,I2,D4(B4) + cgib R1,I2,M3,D4(B4) cgib<m> R1,I2,D4(B4) + cij R1,I2,M3,I4 cij<m> R1,I2,I4 + cgij R1,I2,M3,I4 cgij<m> R1,I2,I4 + crt R1,R2,M3 crt<m> R1,R2 + cgrt R1,R2,M3 cgrt<m> R1,R2 + cit R1,I2,M3 cit<m> R1,I2 + cgit R1,I2,M3 cgit<m> R1,I2 + clrb R1,R2,M3,D4(B4) clrb<m> R1,R2,D4(B4) + clgrb R1,R2,M3,D4(B4) clgrb<m> R1,R2,D4(B4) + clrj R1,R2,M3,I4 clrj<m> R1,R2,I4 + clgrj R1,R2,M3,I4 clgrj<m> R1,R2,I4 + clib R1,I2,M3,D4(B4) clib<m> R1,I2,D4(B4) + clgib R1,I2,M3,D4(B4) clgib<m> R1,I2,D4(B4) + clij R1,I2,M3,I4 clij<m> R1,I2,I4 + clgij R1,I2,M3,I4 clgij<m> R1,I2,I4 + clrt R1,R2,M3 clrt<m> R1,R2 + clgrt R1,R2,M3 clgrt<m> R1,R2 + clfit R1,I2,M3 clfit<m> R1,I2 + clgit R1,I2,M3 clgit<m> R1,I2 + + In the mnemonic for a compare and branch and compare and trap +instruction the condition code string <m> can be any of the following: + + h jump on A high + nle jump on not low or equal + l jump on A low + nhe jump on not high or equal + ne jump on A not equal B + lh jump on low or high + e jump on A equal B + nlh jump on not low or high + nl jump on A not low + he jump on high or equal + nh jump on A not high + le jump on low or equal + + +File: as.info, Node: s390 Operand Modifier, Next: s390 Instruction Marker, Prev: s390 Aliases, Up: s390 Syntax + +9.30.3.6 Instruction Operand Modifier +..................................... + +If a symbol modifier is attached to a symbol in an expression for an +instruction operand field, the symbol term is replaced with a reference +to an object in the global offset table (GOT) or the procedure linkage +table (PLT). The following expressions are allowed: `symbol@modifier + +constant', `symbol@modifier + label + constant', and `symbol@modifier - +label + constant'. The term `symbol' is the symbol that will be +entered into the GOT or PLT, `label' is a local label, and `constant' +is an arbitrary expression that the assembler can evaluate to a +constant value. + + The term `(symbol + constant1)@modifier +/- label + constant2' is +also accepted but a warning message is printed and the term is +converted to `symbol@modifier +/- label + constant1 + constant2'. + +`@got' +`@got12' + The @got modifier can be used for displacement fields, 16-bit + immediate fields and 32-bit pc-relative immediate fields. The + @got12 modifier is synonym to @got. The symbol is added to the + GOT. For displacement fields and 16-bit immediate fields the + symbol term is replaced with the offset from the start of the GOT + to the GOT slot for the symbol. For a 32-bit pc-relative field + the pc-relative offset to the GOT slot from the current + instruction address is used. + +`@gotent' + The @gotent modifier can be used for 32-bit pc-relative immediate + fields. The symbol is added to the GOT and the symbol term is + replaced with the pc-relative offset from the current instruction + to the GOT slot for the symbol. + +`@gotoff' + The @gotoff modifier can be used for 16-bit immediate fields. The + symbol term is replaced with the offset from the start of the GOT + to the address of the symbol. + +`@gotplt' + The @gotplt modifier can be used for displacement fields, 16-bit + immediate fields, and 32-bit pc-relative immediate fields. A + procedure linkage table entry is generated for the symbol and a + jump slot for the symbol is added to the GOT. For displacement + fields and 16-bit immediate fields the symbol term is replaced + with the offset from the start of the GOT to the jump slot for the + symbol. For a 32-bit pc-relative field the pc-relative offset to + the jump slot from the current instruction address is used. + +`@plt' + The @plt modifier can be used for 16-bit and 32-bit pc-relative + immediate fields. A procedure linkage table entry is generated for + the symbol. The symbol term is replaced with the relative offset + from the current instruction to the PLT entry for the symbol. + +`@pltoff' + The @pltoff modifier can be used for 16-bit immediate fields. The + symbol term is replaced with the offset from the start of the PLT + to the address of the symbol. + +`@gotntpoff' + The @gotntpoff modifier can be used for displacement fields. The + symbol is added to the static TLS block and the negated offset to + the symbol in the static TLS block is added to the GOT. The symbol + term is replaced with the offset to the GOT slot from the start of + the GOT. + +`@indntpoff' + The @indntpoff modifier can be used for 32-bit pc-relative + immediate fields. The symbol is added to the static TLS block and + the negated offset to the symbol in the static TLS block is added + to the GOT. The symbol term is replaced with the pc-relative + offset to the GOT slot from the current instruction address. + + For more information about the thread local storage modifiers +`gotntpoff' and `indntpoff' see the ELF extension documentation `ELF +Handling For Thread-Local Storage'. + + +File: as.info, Node: s390 Instruction Marker, Next: s390 Literal Pool Entries, Prev: s390 Operand Modifier, Up: s390 Syntax + +9.30.3.7 Instruction Marker +........................... + +The thread local storage instruction markers are used by the linker to +perform code optimization. + +`:tls_load' + The :tls_load marker is used to flag the load instruction in the + initial exec TLS model that retrieves the offset from the thread + pointer to a thread local storage variable from the GOT. + +`:tls_gdcall' + The :tls_gdcall marker is used to flag the branch-and-save + instruction to the __tls_get_offset function in the global dynamic + TLS model. + +`:tls_ldcall' + The :tls_ldcall marker is used to flag the branch-and-save + instruction to the __tls_get_offset function in the local dynamic + TLS model. + + For more information about the thread local storage instruction +marker and the linker optimizations see the ELF extension documentation +`ELF Handling For Thread-Local Storage'. + + +File: as.info, Node: s390 Literal Pool Entries, Prev: s390 Instruction Marker, Up: s390 Syntax + +9.30.3.8 Literal Pool Entries +............................. + +A literal pool is a collection of values. To access the values a pointer +to the literal pool is loaded to a register, the literal pool register. +Usually, register %r13 is used as the literal pool register (*Note s390 +Register::). Literal pool entries are created by adding the suffix +:lit1, :lit2, :lit4, or :lit8 to the end of an expression for an +instruction operand. The expression is added to the literal pool and the +operand is replaced with the offset to the literal in the literal pool. + +`:lit1' + The literal pool entry is created as an 8-bit value. An operand + modifier must not be used for the original expression. + +`:lit2' + The literal pool entry is created as a 16 bit value. The operand + modifier @got may be used in the original expression. The term + `x@got:lit2' will put the got offset for the global symbol x to + the literal pool as 16 bit value. + +`:lit4' + The literal pool entry is created as a 32-bit value. The operand + modifier @got and @plt may be used in the original expression. The + term `x@got:lit4' will put the got offset for the global symbol x + to the literal pool as a 32-bit value. The term `x@plt:lit4' will + put the plt offset for the global symbol x to the literal pool as + a 32-bit value. + +`:lit8' + The literal pool entry is created as a 64-bit value. The operand + modifier @got and @plt may be used in the original expression. The + term `x@got:lit8' will put the got offset for the global symbol x + to the literal pool as a 64-bit value. The term `x@plt:lit8' will + put the plt offset for the global symbol x to the literal pool as + a 64-bit value. + + The assembler directive `.ltorg' is used to emit all literal pool +entries to the current position. + + +File: as.info, Node: s390 Directives, Next: s390 Floating Point, Prev: s390 Syntax, Up: S/390-Dependent + +9.30.4 Assembler Directives +--------------------------- + +`as' for s390 supports all of the standard ELF assembler directives as +outlined in the main part of this document. Some directives have been +extended and there are some additional directives, which are only +available for the s390 `as'. + +`.insn' + This directive permits the numeric representation of an + instructions and makes the assembler insert the operands according + to one of the instructions formats for `.insn' (*Note s390 + Formats::). For example, the instruction `l %r1,24(%r15)' could + be written as `.insn rx,0x58000000,%r1,24(%r15)'. + +`.short' +`.long' +`.quad' + This directive places one or more 16-bit (.short), 32-bit (.long), + or 64-bit (.quad) values into the current section. If an ELF or + TLS modifier is used only the following expressions are allowed: + `symbol@modifier + constant', `symbol@modifier + label + + constant', and `symbol@modifier - label + constant'. The + following modifiers are available: + `@got' + `@got12' + The @got modifier can be used for .short, .long and .quad. + The @got12 modifier is synonym to @got. The symbol is added + to the GOT. The symbol term is replaced with offset from the + start of the GOT to the GOT slot for the symbol. + + `@gotoff' + The @gotoff modifier can be used for .short, .long and .quad. + The symbol term is replaced with the offset from the start of + the GOT to the address of the symbol. + + `@gotplt' + The @gotplt modifier can be used for .long and .quad. A + procedure linkage table entry is generated for the symbol and + a jump slot for the symbol is added to the GOT. The symbol + term is replaced with the offset from the start of the GOT to + the jump slot for the symbol. + + `@plt' + The @plt modifier can be used for .long and .quad. A + procedure linkage table entry us generated for the symbol. + The symbol term is replaced with the address of the PLT entry + for the symbol. + + `@pltoff' + The @pltoff modifier can be used for .short, .long and .quad. + The symbol term is replaced with the offset from the start of + the PLT to the address of the symbol. + + `@tlsgd' + `@tlsldm' + The @tlsgd and @tlsldm modifier can be used for .long and + .quad. A tls_index structure for the symbol is added to the + GOT. The symbol term is replaced with the offset from the + start of the GOT to the tls_index structure. + + `@gotntpoff' + `@indntpoff' + The @gotntpoff and @indntpoff modifier can be used for .long + and .quad. The symbol is added to the static TLS block and + the negated offset to the symbol in the static TLS block is + added to the GOT. For @gotntpoff the symbol term is replaced + with the offset from the start of the GOT to the GOT slot, + for @indntpoff the symbol term is replaced with the address + of the GOT slot. + + `@dtpoff' + The @dtpoff modifier can be used for .long and .quad. The + symbol term is replaced with the offset of the symbol + relative to the start of the TLS block it is contained in. + + `@ntpoff' + The @ntpoff modifier can be used for .long and .quad. The + symbol term is replaced with the offset of the symbol + relative to the TCB pointer. + + For more information about the thread local storage modifiers see + the ELF extension documentation `ELF Handling For Thread-Local + Storage'. + +`.ltorg' + This directive causes the current contents of the literal pool to + be dumped to the current location (*Note s390 Literal Pool + Entries::). + + +File: as.info, Node: s390 Floating Point, Prev: s390 Directives, Up: S/390-Dependent + +9.30.5 Floating Point +--------------------- + +The assembler recognizes both the IEEE floating-point instruction and +the hexadecimal floating-point instructions. The floating-point +constructors `.float', `.single', and `.double' always emit the IEEE +format. To assemble hexadecimal floating-point constants the `.long' +and `.quad' directives must be used. + + +File: as.info, Node: SCORE-Dependent, Next: Sparc-Dependent, Prev: S/390-Dependent, Up: Machine Dependencies + +9.31 SCORE Dependent Features +============================= + +* Menu: + +* SCORE-Opts:: Assembler options +* SCORE-Pseudo:: SCORE Assembler Directives + + +File: as.info, Node: SCORE-Opts, Next: SCORE-Pseudo, Up: SCORE-Dependent + +9.31.1 Options +-------------- + +The following table lists all available SCORE options. + +`-G NUM' + This option sets the largest size of an object that can be + referenced implicitly with the `gp' register. The default value is + 8. + +`-EB' + Assemble code for a big-endian cpu + +`-EL' + Assemble code for a little-endian cpu + +`-FIXDD' + Assemble code for fix data dependency + +`-NWARN' + Assemble code for no warning message for fix data dependency + +`-SCORE5' + Assemble code for target is SCORE5 + +`-SCORE5U' + Assemble code for target is SCORE5U + +`-SCORE7' + Assemble code for target is SCORE7, this is default setting + +`-SCORE3' + Assemble code for target is SCORE3 + +`-march=score7' + Assemble code for target is SCORE7, this is default setting + +`-march=score3' + Assemble code for target is SCORE3 + +`-USE_R1' + Assemble code for no warning message when using temp register r1 + +`-KPIC' + Generate code for PIC. This option tells the assembler to generate + score position-independent macro expansions. It also tells the + assembler to mark the output file as PIC. + +`-O0' + Assembler will not perform any optimizations + +`-V' + Sunplus release version + + + +File: as.info, Node: SCORE-Pseudo, Prev: SCORE-Opts, Up: SCORE-Dependent + +9.31.2 SCORE Assembler Directives +--------------------------------- + +A number of assembler directives are available for SCORE. The +following table is far from complete. + +`.set nwarn' + Let the assembler not to generate warnings if the source machine + language instructions happen data dependency. + +`.set fixdd' + Let the assembler to insert bubbles (32 bit nop instruction / 16 + bit nop! Instruction) if the source machine language instructions + happen data dependency. + +`.set nofixdd' + Let the assembler to generate warnings if the source machine + language instructions happen data dependency. (Default) + +`.set r1' + Let the assembler not to generate warnings if the source program + uses r1. allow user to use r1 + +`set nor1' + Let the assembler to generate warnings if the source program uses + r1. (Default) + +`.sdata' + Tell the assembler to add subsequent data into the sdata section + +`.rdata' + Tell the assembler to add subsequent data into the rdata section + +`.frame "frame-register", "offset", "return-pc-register"' + Describe a stack frame. "frame-register" is the frame register, + "offset" is the distance from the frame register to the virtual + frame pointer, "return-pc-register" is the return program register. + You must use ".ent" before ".frame" and only one ".frame" can be + used per ".ent". + +`.mask "bitmask", "frameoffset"' + Indicate which of the integer registers are saved in the current + function's stack frame, this is for the debugger to explain the + frame chain. + +`.ent "proc-name"' + Set the beginning of the procedure "proc_name". Use this directive + when you want to generate information for the debugger. + +`.end proc-name' + Set the end of a procedure. Use this directive to generate + information for the debugger. + +`.bss' + Switch the destination of following statements into the bss + section, which is used for data that is uninitialized anywhere. + + + +File: as.info, Node: SH-Dependent, Next: SH64-Dependent, Prev: MSP430-Dependent, Up: Machine Dependencies + +9.32 Renesas / SuperH SH Dependent Features +=========================================== + +* Menu: + +* SH Options:: Options +* SH Syntax:: Syntax +* SH Floating Point:: Floating Point +* SH Directives:: SH Machine Directives +* SH Opcodes:: Opcodes + + +File: as.info, Node: SH Options, Next: SH Syntax, Up: SH-Dependent + +9.32.1 Options +-------------- + +`as' has following command-line options for the Renesas (formerly +Hitachi) / SuperH SH family. + +`--little' + Generate little endian code. + +`--big' + Generate big endian code. + +`--relax' + Alter jump instructions for long displacements. + +`--small' + Align sections to 4 byte boundaries, not 16. + +`--dsp' + Enable sh-dsp insns, and disable sh3e / sh4 insns. + +`--renesas' + Disable optimization with section symbol for compatibility with + Renesas assembler. + +`--allow-reg-prefix' + Allow '$' as a register name prefix. + +`--isa=sh4 | sh4a' + Specify the sh4 or sh4a instruction set. + +`--isa=dsp' + Enable sh-dsp insns, and disable sh3e / sh4 insns. + +`--isa=fp' + Enable sh2e, sh3e, sh4, and sh4a insn sets. + +`--isa=all' + Enable sh1, sh2, sh2e, sh3, sh3e, sh4, sh4a, and sh-dsp insn sets. + +`-h-tick-hex' + Support H'00 style hex constants in addition to 0x00 style. + + + +File: as.info, Node: SH Syntax, Next: SH Floating Point, Prev: SH Options, Up: SH-Dependent + +9.32.2 Syntax +------------- + +* Menu: + +* SH-Chars:: Special Characters +* SH-Regs:: Register Names +* SH-Addressing:: Addressing Modes + + +File: as.info, Node: SH-Chars, Next: SH-Regs, Up: SH Syntax + +9.32.2.1 Special Characters +........................... + +`!' is the line comment character. + + You can use `;' instead of a newline to separate statements. + + Since `$' has no special meaning, you may use it in symbol names. + + +File: as.info, Node: SH-Regs, Next: SH-Addressing, Prev: SH-Chars, Up: SH Syntax + +9.32.2.2 Register Names +....................... + +You can use the predefined symbols `r0', `r1', `r2', `r3', `r4', `r5', +`r6', `r7', `r8', `r9', `r10', `r11', `r12', `r13', `r14', and `r15' to +refer to the SH registers. + + The SH also has these control registers: + +`pr' + procedure register (holds return address) + +`pc' + program counter + +`mach' +`macl' + high and low multiply accumulator registers + +`sr' + status register + +`gbr' + global base register + +`vbr' + vector base register (for interrupt vectors) + + +File: as.info, Node: SH-Addressing, Prev: SH-Regs, Up: SH Syntax + +9.32.2.3 Addressing Modes +......................... + +`as' understands the following addressing modes for the SH. `RN' in +the following refers to any of the numbered registers, but _not_ the +control registers. + +`RN' + Register direct + +`@RN' + Register indirect + +`@-RN' + Register indirect with pre-decrement + +`@RN+' + Register indirect with post-increment + +`@(DISP, RN)' + Register indirect with displacement + +`@(R0, RN)' + Register indexed + +`@(DISP, GBR)' + `GBR' offset + +`@(R0, GBR)' + GBR indexed + +`ADDR' +`@(DISP, PC)' + PC relative address (for branch or for addressing memory). The + `as' implementation allows you to use the simpler form ADDR + anywhere a PC relative address is called for; the alternate form + is supported for compatibility with other assemblers. + +`#IMM' + Immediate data + + +File: as.info, Node: SH Floating Point, Next: SH Directives, Prev: SH Syntax, Up: SH-Dependent + +9.32.3 Floating Point +--------------------- + +SH2E, SH3E and SH4 groups have on-chip floating-point unit (FPU). Other +SH groups can use `.float' directive to generate IEEE floating-point +numbers. + + SH2E and SH3E support single-precision floating point calculations as +well as entirely PCAPI compatible emulation of double-precision +floating point calculations. SH2E and SH3E instructions are a subset of +the floating point calculations conforming to the IEEE754 standard. + + In addition to single-precision and double-precision floating-point +operation capability, the on-chip FPU of SH4 has a 128-bit graphic +engine that enables 32-bit floating-point data to be processed 128 bits +at a time. It also supports 4 * 4 array operations and inner product +operations. Also, a superscalar architecture is employed that enables +simultaneous execution of two instructions (including FPU +instructions), providing performance of up to twice that of +conventional architectures at the same frequency. + + +File: as.info, Node: SH Directives, Next: SH Opcodes, Prev: SH Floating Point, Up: SH-Dependent + +9.32.4 SH Machine Directives +---------------------------- + +`uaword' +`ualong' + `as' will issue a warning when a misaligned `.word' or `.long' + directive is used. You may use `.uaword' or `.ualong' to indicate + that the value is intentionally misaligned. + + +File: as.info, Node: SH Opcodes, Prev: SH Directives, Up: SH-Dependent + +9.32.5 Opcodes +-------------- + +For detailed information on the SH machine instruction set, see +`SH-Microcomputer User's Manual' (Renesas) or `SH-4 32-bit CPU Core +Architecture' (SuperH) and `SuperH (SH) 64-Bit RISC Series' (SuperH). + + `as' implements all the standard SH opcodes. No additional +pseudo-instructions are needed on this family. Note, however, that +because `as' supports a simpler form of PC-relative addressing, you may +simply write (for example) + + mov.l bar,r0 + +where other assemblers might require an explicit displacement to `bar' +from the program counter: + + mov.l @(DISP, PC) + + Here is a summary of SH opcodes: + + Legend: + Rn a numbered register + Rm another numbered register + #imm immediate data + disp displacement + disp8 8-bit displacement + disp12 12-bit displacement + + add #imm,Rn lds.l @Rn+,PR + add Rm,Rn mac.w @Rm+,@Rn+ + addc Rm,Rn mov #imm,Rn + addv Rm,Rn mov Rm,Rn + and #imm,R0 mov.b Rm,@(R0,Rn) + and Rm,Rn mov.b Rm,@-Rn + and.b #imm,@(R0,GBR) mov.b Rm,@Rn + bf disp8 mov.b @(disp,Rm),R0 + bra disp12 mov.b @(disp,GBR),R0 + bsr disp12 mov.b @(R0,Rm),Rn + bt disp8 mov.b @Rm+,Rn + clrmac mov.b @Rm,Rn + clrt mov.b R0,@(disp,Rm) + cmp/eq #imm,R0 mov.b R0,@(disp,GBR) + cmp/eq Rm,Rn mov.l Rm,@(disp,Rn) + cmp/ge Rm,Rn mov.l Rm,@(R0,Rn) + cmp/gt Rm,Rn mov.l Rm,@-Rn + cmp/hi Rm,Rn mov.l Rm,@Rn + cmp/hs Rm,Rn mov.l @(disp,Rn),Rm + cmp/pl Rn mov.l @(disp,GBR),R0 + cmp/pz Rn mov.l @(disp,PC),Rn + cmp/str Rm,Rn mov.l @(R0,Rm),Rn + div0s Rm,Rn mov.l @Rm+,Rn + div0u mov.l @Rm,Rn + div1 Rm,Rn mov.l R0,@(disp,GBR) + exts.b Rm,Rn mov.w Rm,@(R0,Rn) + exts.w Rm,Rn mov.w Rm,@-Rn + extu.b Rm,Rn mov.w Rm,@Rn + extu.w Rm,Rn mov.w @(disp,Rm),R0 + jmp @Rn mov.w @(disp,GBR),R0 + jsr @Rn mov.w @(disp,PC),Rn + ldc Rn,GBR mov.w @(R0,Rm),Rn + ldc Rn,SR mov.w @Rm+,Rn + ldc Rn,VBR mov.w @Rm,Rn + ldc.l @Rn+,GBR mov.w R0,@(disp,Rm) + ldc.l @Rn+,SR mov.w R0,@(disp,GBR) + ldc.l @Rn+,VBR mova @(disp,PC),R0 + lds Rn,MACH movt Rn + lds Rn,MACL muls Rm,Rn + lds Rn,PR mulu Rm,Rn + lds.l @Rn+,MACH neg Rm,Rn + lds.l @Rn+,MACL negc Rm,Rn + + nop stc VBR,Rn + not Rm,Rn stc.l GBR,@-Rn + or #imm,R0 stc.l SR,@-Rn + or Rm,Rn stc.l VBR,@-Rn + or.b #imm,@(R0,GBR) sts MACH,Rn + rotcl Rn sts MACL,Rn + rotcr Rn sts PR,Rn + rotl Rn sts.l MACH,@-Rn + rotr Rn sts.l MACL,@-Rn + rte sts.l PR,@-Rn + rts sub Rm,Rn + sett subc Rm,Rn + shal Rn subv Rm,Rn + shar Rn swap.b Rm,Rn + shll Rn swap.w Rm,Rn + shll16 Rn tas.b @Rn + shll2 Rn trapa #imm + shll8 Rn tst #imm,R0 + shlr Rn tst Rm,Rn + shlr16 Rn tst.b #imm,@(R0,GBR) + shlr2 Rn xor #imm,R0 + shlr8 Rn xor Rm,Rn + sleep xor.b #imm,@(R0,GBR) + stc GBR,Rn xtrct Rm,Rn + stc SR,Rn + + +File: as.info, Node: SH64-Dependent, Next: PDP-11-Dependent, Prev: SH-Dependent, Up: Machine Dependencies + +9.33 SuperH SH64 Dependent Features +=================================== + +* Menu: + +* SH64 Options:: Options +* SH64 Syntax:: Syntax +* SH64 Directives:: SH64 Machine Directives +* SH64 Opcodes:: Opcodes + + +File: as.info, Node: SH64 Options, Next: SH64 Syntax, Up: SH64-Dependent + +9.33.1 Options +-------------- + +`-isa=sh4 | sh4a' + Specify the sh4 or sh4a instruction set. + +`-isa=dsp' + Enable sh-dsp insns, and disable sh3e / sh4 insns. + +`-isa=fp' + Enable sh2e, sh3e, sh4, and sh4a insn sets. + +`-isa=all' + Enable sh1, sh2, sh2e, sh3, sh3e, sh4, sh4a, and sh-dsp insn sets. + +`-isa=shmedia | -isa=shcompact' + Specify the default instruction set. `SHmedia' specifies the + 32-bit opcodes, and `SHcompact' specifies the 16-bit opcodes + compatible with previous SH families. The default depends on the + ABI selected; the default for the 64-bit ABI is SHmedia, and the + default for the 32-bit ABI is SHcompact. If neither the ABI nor + the ISA is specified, the default is 32-bit SHcompact. + + Note that the `.mode' pseudo-op is not permitted if the ISA is not + specified on the command line. + +`-abi=32 | -abi=64' + Specify the default ABI. If the ISA is specified and the ABI is + not, the default ABI depends on the ISA, with SHmedia defaulting + to 64-bit and SHcompact defaulting to 32-bit. + + Note that the `.abi' pseudo-op is not permitted if the ABI is not + specified on the command line. When the ABI is specified on the + command line, any `.abi' pseudo-ops in the source must match it. + +`-shcompact-const-crange' + Emit code-range descriptors for constants in SHcompact code + sections. + +`-no-mix' + Disallow SHmedia code in the same section as constants and + SHcompact code. + +`-no-expand' + Do not expand MOVI, PT, PTA or PTB instructions. + +`-expand-pt32' + With -abi=64, expand PT, PTA and PTB instructions to 32 bits only. + +`-h-tick-hex' + Support H'00 style hex constants in addition to 0x00 style. + + + +File: as.info, Node: SH64 Syntax, Next: SH64 Directives, Prev: SH64 Options, Up: SH64-Dependent + +9.33.2 Syntax +------------- + +* Menu: + +* SH64-Chars:: Special Characters +* SH64-Regs:: Register Names +* SH64-Addressing:: Addressing Modes + + +File: as.info, Node: SH64-Chars, Next: SH64-Regs, Up: SH64 Syntax + +9.33.2.1 Special Characters +........................... + +`!' is the line comment character. + + You can use `;' instead of a newline to separate statements. + + Since `$' has no special meaning, you may use it in symbol names. + + +File: as.info, Node: SH64-Regs, Next: SH64-Addressing, Prev: SH64-Chars, Up: SH64 Syntax + +9.33.2.2 Register Names +....................... + +You can use the predefined symbols `r0' through `r63' to refer to the +SH64 general registers, `cr0' through `cr63' for control registers, +`tr0' through `tr7' for target address registers, `fr0' through `fr63' +for single-precision floating point registers, `dr0' through `dr62' +(even numbered registers only) for double-precision floating point +registers, `fv0' through `fv60' (multiples of four only) for +single-precision floating point vectors, `fp0' through `fp62' (even +numbered registers only) for single-precision floating point pairs, +`mtrx0' through `mtrx48' (multiples of 16 only) for 4x4 matrices of +single-precision floating point registers, `pc' for the program +counter, and `fpscr' for the floating point status and control register. + + You can also refer to the control registers by the mnemonics `sr', +`ssr', `pssr', `intevt', `expevt', `pexpevt', `tra', `spc', `pspc', +`resvec', `vbr', `tea', `dcr', `kcr0', `kcr1', `ctc', and `usr'. + + +File: as.info, Node: SH64-Addressing, Prev: SH64-Regs, Up: SH64 Syntax + +9.33.2.3 Addressing Modes +......................... + +SH64 operands consist of either a register or immediate value. The +immediate value can be a constant or label reference (or portion of a +label reference), as in this example: + + movi 4,r2 + pt function, tr4 + movi (function >> 16) & 65535,r0 + shori function & 65535, r0 + ld.l r0,4,r0 + + Instruction label references can reference labels in either SHmedia +or SHcompact. To differentiate between the two, labels in SHmedia +sections will always have the least significant bit set (i.e. they will +be odd), which SHcompact labels will have the least significant bit +reset (i.e. they will be even). If you need to reference the actual +address of a label, you can use the `datalabel' modifier, as in this +example: + + .long function + .long datalabel function + + In that example, the first longword may or may not have the least +significant bit set depending on whether the label is an SHmedia label +or an SHcompact label. The second longword will be the actual address +of the label, regardless of what type of label it is. + + +File: as.info, Node: SH64 Directives, Next: SH64 Opcodes, Prev: SH64 Syntax, Up: SH64-Dependent + +9.33.3 SH64 Machine Directives +------------------------------ + +In addition to the SH directives, the SH64 provides the following +directives: + +`.mode [shmedia|shcompact]' +`.isa [shmedia|shcompact]' + Specify the ISA for the following instructions (the two directives + are equivalent). Note that programs such as `objdump' rely on + symbolic labels to determine when such mode switches occur (by + checking the least significant bit of the label's address), so + such mode/isa changes should always be followed by a label (in + practice, this is true anyway). Note that you cannot use these + directives if you didn't specify an ISA on the command line. + +`.abi [32|64]' + Specify the ABI for the following instructions. Note that you + cannot use this directive unless you specified an ABI on the + command line, and the ABIs specified must match. + +`.uaquad' + Like .uaword and .ualong, this allows you to specify an + intentionally unaligned quadword (64 bit word). + + + +File: as.info, Node: SH64 Opcodes, Prev: SH64 Directives, Up: SH64-Dependent + +9.33.4 Opcodes +-------------- + +For detailed information on the SH64 machine instruction set, see +`SuperH 64 bit RISC Series Architecture Manual' (SuperH, Inc.). + + `as' implements all the standard SH64 opcodes. In addition, the +following pseudo-opcodes may be expanded into one or more alternate +opcodes: + +`movi' + If the value doesn't fit into a standard `movi' opcode, `as' will + replace the `movi' with a sequence of `movi' and `shori' opcodes. + +`pt' + This expands to a sequence of `movi' and `shori' opcode, followed + by a `ptrel' opcode, or to a `pta' or `ptb' opcode, depending on + the label referenced. + + + +File: as.info, Node: Sparc-Dependent, Next: TIC54X-Dependent, Prev: SCORE-Dependent, Up: Machine Dependencies + +9.34 SPARC Dependent Features +============================= + +* Menu: + +* Sparc-Opts:: Options +* Sparc-Aligned-Data:: Option to enforce aligned data +* Sparc-Syntax:: Syntax +* Sparc-Float:: Floating Point +* Sparc-Directives:: Sparc Machine Directives + + +File: as.info, Node: Sparc-Opts, Next: Sparc-Aligned-Data, Up: Sparc-Dependent + +9.34.1 Options +-------------- + +The SPARC chip family includes several successive versions, using the +same core instruction set, but including a few additional instructions +at each version. There are exceptions to this however. For details on +what instructions each variant supports, please see the chip's +architecture reference manual. + + By default, `as' assumes the core instruction set (SPARC v6), but +"bumps" the architecture level as needed: it switches to successively +higher architectures as it encounters instructions that only exist in +the higher levels. + + If not configured for SPARC v9 (`sparc64-*-*') GAS will not bump +past sparclite by default, an option must be passed to enable the v9 +instructions. + + GAS treats sparclite as being compatible with v8, unless an +architecture is explicitly requested. SPARC v9 is always incompatible +with sparclite. + +`-Av6 | -Av7 | -Av8 | -Asparclet | -Asparclite' +`-Av8plus | -Av8plusa | -Av9 | -Av9a' + Use one of the `-A' options to select one of the SPARC + architectures explicitly. If you select an architecture + explicitly, `as' reports a fatal error if it encounters an + instruction or feature requiring an incompatible or higher level. + + `-Av8plus' and `-Av8plusa' select a 32 bit environment. + + `-Av9' and `-Av9a' select a 64 bit environment and are not + available unless GAS is explicitly configured with 64 bit + environment support. + + `-Av8plusa' and `-Av9a' enable the SPARC V9 instruction set with + UltraSPARC extensions. + +`-xarch=v8plus | -xarch=v8plusa' + For compatibility with the SunOS v9 assembler. These options are + equivalent to -Av8plus and -Av8plusa, respectively. + +`-bump' + Warn whenever it is necessary to switch to another level. If an + architecture level is explicitly requested, GAS will not issue + warnings until that level is reached, and will then bump the level + as required (except between incompatible levels). + +`-32 | -64' + Select the word size, either 32 bits or 64 bits. These options + are only available with the ELF object file format, and require + that the necessary BFD support has been included. + + +File: as.info, Node: Sparc-Aligned-Data, Next: Sparc-Syntax, Prev: Sparc-Opts, Up: Sparc-Dependent + +9.34.2 Enforcing aligned data +----------------------------- + +SPARC GAS normally permits data to be misaligned. For example, it +permits the `.long' pseudo-op to be used on a byte boundary. However, +the native SunOS assemblers issue an error when they see misaligned +data. + + You can use the `--enforce-aligned-data' option to make SPARC GAS +also issue an error about misaligned data, just as the SunOS assemblers +do. + + The `--enforce-aligned-data' option is not the default because gcc +issues misaligned data pseudo-ops when it initializes certain packed +data structures (structures defined using the `packed' attribute). You +may have to assemble with GAS in order to initialize packed data +structures in your own code. + + +File: as.info, Node: Sparc-Syntax, Next: Sparc-Float, Prev: Sparc-Aligned-Data, Up: Sparc-Dependent + +9.34.3 Sparc Syntax +------------------- + +The assembler syntax closely follows The Sparc Architecture Manual, +versions 8 and 9, as well as most extensions defined by Sun for their +UltraSPARC and Niagara line of processors. + +* Menu: + +* Sparc-Chars:: Special Characters +* Sparc-Regs:: Register Names +* Sparc-Constants:: Constant Names +* Sparc-Relocs:: Relocations +* Sparc-Size-Translations:: Size Translations + + +File: as.info, Node: Sparc-Chars, Next: Sparc-Regs, Up: Sparc-Syntax + +9.34.3.1 Special Characters +........................... + +`#' is the line comment character. + + `;' can be used instead of a newline to separate statements. + + +File: as.info, Node: Sparc-Regs, Next: Sparc-Constants, Prev: Sparc-Chars, Up: Sparc-Syntax + +9.34.3.2 Register Names +....................... + +The Sparc integer register file is broken down into global, outgoing, +local, and incoming. + + * The 8 global registers are referred to as `%gN'. + + * The 8 outgoing registers are referred to as `%oN'. + + * The 8 local registers are referred to as `%lN'. + + * The 8 incoming registers are referred to as `%iN'. + + * The frame pointer register `%i6' can be referenced using the alias + `%fp'. + + * The stack pointer register `%o6' can be referenced using the alias + `%sp'. + + Floating point registers are simply referred to as `%fN'. When +assembling for pre-V9, only 32 floating point registers are available. +For V9 and later there are 64, but there are restrictions when +referencing the upper 32 registers. They can only be accessed as +double or quad, and thus only even or quad numbered accesses are +allowed. For example, `%f34' is a legal floating point register, but +`%f35' is not. + + Certain V9 instructions allow access to ancillary state registers. +Most simply they can be referred to as `%asrN' where N can be from 16 +to 31. However, there are some aliases defined to reference ASR +registers defined for various UltraSPARC processors: + + * The tick compare register is referred to as `%tick_cmpr'. + + * The system tick register is referred to as `%stick'. An alias, + `%sys_tick', exists but is deprecated and should not be used by + new software. + + * The system tick compare register is referred to as `%stick_cmpr'. + An alias, `%sys_tick_cmpr', exists but is deprecated and should + not be used by new software. + + * The software interrupt register is referred to as `%softint'. + + * The set software interrupt register is referred to as + `%set_softint'. The mnemonic `%softint_set' is provided as an + alias. + + * The clear software interrupt register is referred to as + `%clear_softint'. The mnemonic `%softint_clear' is provided as an + alias. + + * The performance instrumentation counters register is referred to as + `%pic'. + + * The performance control register is referred to as `%pcr'. + + * The graphics status register is referred to as `%gsr'. + + * The V9 dispatch control register is referred to as `%dcr'. + + Various V9 branch and conditional move instructions allow +specification of which set of integer condition codes to test. These +are referred to as `%xcc' and `%icc'. + + In V9, there are 4 sets of floating point condition codes which are +referred to as `%fccN'. + + Several special privileged and non-privileged registers exist: + + * The V9 address space identifier register is referred to as `%asi'. + + * The V9 restorable windows register is referred to as `%canrestore'. + + * The V9 savable windows register is referred to as `%cansave'. + + * The V9 clean windows register is referred to as `%cleanwin'. + + * The V9 current window pointer register is referred to as `%cwp'. + + * The floating-point queue register is referred to as `%fq'. + + * The V8 co-processor queue register is referred to as `%cq'. + + * The floating point status register is referred to as `%fsr'. + + * The other windows register is referred to as `%otherwin'. + + * The V9 program counter register is referred to as `%pc'. + + * The V9 next program counter register is referred to as `%npc'. + + * The V9 processor interrupt level register is referred to as `%pil'. + + * The V9 processor state register is referred to as `%pstate'. + + * The trap base address register is referred to as `%tba'. + + * The V9 tick register is referred to as `%tick'. + + * The V9 trap level is referred to as `%tl'. + + * The V9 trap program counter is referred to as `%tpc'. + + * The V9 trap next program counter is referred to as `%tnpc'. + + * The V9 trap state is referred to as `%tstate'. + + * The V9 trap type is referred to as `%tt'. + + * The V9 condition codes is referred to as `%ccr'. + + * The V9 floating-point registers state is referred to as `%fprs'. + + * The V9 version register is referred to as `%ver'. + + * The V9 window state register is referred to as `%wstate'. + + * The Y register is referred to as `%y'. + + * The V8 window invalid mask register is referred to as `%wim'. + + * The V8 processor state register is referred to as `%psr'. + + * The V9 global register level register is referred to as `%gl'. + + Several special register names exist for hypervisor mode code: + + * The hyperprivileged processor state register is referred to as + `%hpstate'. + + * The hyperprivileged trap state register is referred to as + `%htstate'. + + * The hyperprivileged interrupt pending register is referred to as + `%hintp'. + + * The hyperprivileged trap base address register is referred to as + `%htba'. + + * The hyperprivileged implementation version register is referred to + as `%hver'. + + * The hyperprivileged system tick compare register is referred to as + `%hstick_cmpr'. Note that there is no `%hstick' register, the + normal `%stick' is used. + + +File: as.info, Node: Sparc-Constants, Next: Sparc-Relocs, Prev: Sparc-Regs, Up: Sparc-Syntax + +9.34.3.3 Constants +.................. + +Several Sparc instructions take an immediate operand field for which +mnemonic names exist. Two such examples are `membar' and `prefetch'. +Another example are the set of V9 memory access instruction that allow +specification of an address space identifier. + + The `membar' instruction specifies a memory barrier that is the +defined by the operand which is a bitmask. The supported mask +mnemonics are: + + * `#Sync' requests that all operations (including nonmemory + reference operations) appearing prior to the `membar' must have + been performed and the effects of any exceptions become visible + before any instructions after the `membar' may be initiated. This + corresponds to `membar' cmask field bit 2. + + * `#MemIssue' requests that all memory reference operations + appearing prior to the `membar' must have been performed before + any memory operation after the `membar' may be initiated. This + corresponds to `membar' cmask field bit 1. + + * `#Lookaside' requests that a store appearing prior to the `membar' + must complete before any load following the `membar' referencing + the same address can be initiated. This corresponds to `membar' + cmask field bit 0. + + * `#StoreStore' defines that the effects of all stores appearing + prior to the `membar' instruction must be visible to all + processors before the effect of any stores following the `membar'. + Equivalent to the deprecated `stbar' instruction. This + corresponds to `membar' mmask field bit 3. + + * `#LoadStore' defines all loads appearing prior to the `membar' + instruction must have been performed before the effect of any + stores following the `membar' is visible to any other processor. + This corresponds to `membar' mmask field bit 2. + + * `#StoreLoad' defines that the effects of all stores appearing + prior to the `membar' instruction must be visible to all + processors before loads following the `membar' may be performed. + This corresponds to `membar' mmask field bit 1. + + * `#LoadLoad' defines that all loads appearing prior to the `membar' + instruction must have been performed before any loads following + the `membar' may be performed. This corresponds to `membar' mmask + field bit 0. + + + These values can be ored together, for example: + + membar #Sync + membar #StoreLoad | #LoadLoad + membar #StoreLoad | #StoreStore + + The `prefetch' and `prefetcha' instructions take a prefetch function +code. The following prefetch function code constant mnemonics are +available: + + * `#n_reads' requests a prefetch for several reads, and corresponds + to a prefetch function code of 0. + + `#one_read' requests a prefetch for one read, and corresponds to a + prefetch function code of 1. + + `#n_writes' requests a prefetch for several writes (and possibly + reads), and corresponds to a prefetch function code of 2. + + `#one_write' requests a prefetch for one write, and corresponds to + a prefetch function code of 3. + + `#page' requests a prefetch page, and corresponds to a prefetch + function code of 4. + + `#invalidate' requests a prefetch invalidate, and corresponds to a + prefetch function code of 16. + + `#unified' requests a prefetch to the nearest unified cache, and + corresponds to a prefetch function code of 17. + + `#n_reads_strong' requests a strong prefetch for several reads, + and corresponds to a prefetch function code of 20. + + `#one_read_strong' requests a strong prefetch for one read, and + corresponds to a prefetch function code of 21. + + `#n_writes_strong' requests a strong prefetch for several writes, + and corresponds to a prefetch function code of 22. + + `#one_write_strong' requests a strong prefetch for one write, and + corresponds to a prefetch function code of 23. + + Onle one prefetch code may be specified. Here are some examples: + + prefetch [%l0 + %l2], #one_read + prefetch [%g2 + 8], #n_writes + prefetcha [%g1] 0x8, #unified + prefetcha [%o0 + 0x10] %asi, #n_reads + + The actual behavior of a given prefetch function code is processor + specific. If a processor does not implement a given prefetch + function code, it will treat the prefetch instruction as a nop. + + For instructions that accept an immediate address space identifier, + `as' provides many mnemonics corresponding to V9 defined as well + as UltraSPARC and Niagara extended values. For example, `#ASI_P' + and `#ASI_BLK_INIT_QUAD_LDD_AIUS'. See the V9 and processor + specific manuals for details. + + + +File: as.info, Node: Sparc-Relocs, Next: Sparc-Size-Translations, Prev: Sparc-Constants, Up: Sparc-Syntax + +9.34.3.4 Relocations +.................... + +ELF relocations are available as defined in the 32-bit and 64-bit Sparc +ELF specifications. + + `R_SPARC_HI22' is obtained using `%hi' and `R_SPARC_LO10' is +obtained using `%lo'. Likewise `R_SPARC_HIX22' is obtained from `%hix' +and `R_SPARC_LOX10' is obtained using `%lox'. For example: + + sethi %hi(symbol), %g1 + or %g1, %lo(symbol), %g1 + + sethi %hix(symbol), %g1 + xor %g1, %lox(symbol), %g1 + + These "high" mnemonics extract bits 31:10 of their operand, and the +"low" mnemonics extract bits 9:0 of their operand. + + V9 code model relocations can be requested as follows: + + * `R_SPARC_HH22' is requested using `%hh'. It can also be generated + using `%uhi'. + + * `R_SPARC_HM10' is requested using `%hm'. It can also be generated + using `%ulo'. + + * `R_SPARC_LM22' is requested using `%lm'. + + * `R_SPARC_H44' is requested using `%h44'. + + * `R_SPARC_M44' is requested using `%m44'. + + * `R_SPARC_L44' is requested using `%l44'. + + The PC relative relocation `R_SPARC_PC22' can be obtained by +enclosing an operand inside of `%pc22'. Likewise, the `R_SPARC_PC10' +relocation can be obtained using `%pc10'. These are mostly used when +assembling PIC code. For example, the standard PIC sequence on Sparc +to get the base of the global offset table, PC relative, into a +register, can be performed as: + + sethi %pc22(_GLOBAL_OFFSET_TABLE_-4), %l7 + add %l7, %pc10(_GLOBAL_OFFSET_TABLE_+4), %l7 + + Several relocations exist to allow the link editor to potentially +optimize GOT data references. The `R_SPARC_GOTDATA_OP_HIX22' +relocation can obtained by enclosing an operand inside of +`%gdop_hix22'. The `R_SPARC_GOTDATA_OP_LOX10' relocation can obtained +by enclosing an operand inside of `%gdop_lox10'. Likewise, +`R_SPARC_GOTDATA_OP' can be obtained by enclosing an operand inside of +`%gdop'. For example, assuming the GOT base is in register `%l7': + + sethi %gdop_hix22(symbol), %l1 + xor %l1, %gdop_lox10(symbol), %l1 + ld [%l7 + %l1], %l2, %gdop(symbol) + + There are many relocations that can be requested for access to +thread local storage variables. All of the Sparc TLS mnemonics are +supported: + + * `R_SPARC_TLS_GD_HI22' is requested using `%tgd_hi22'. + + * `R_SPARC_TLS_GD_LO10' is requested using `%tgd_lo10'. + + * `R_SPARC_TLS_GD_ADD' is requested using `%tgd_add'. + + * `R_SPARC_TLS_GD_CALL' is requested using `%tgd_call'. + + * `R_SPARC_TLS_LDM_HI22' is requested using `%tldm_hi22'. + + * `R_SPARC_TLS_LDM_LO10' is requested using `%tldm_lo10'. + + * `R_SPARC_TLS_LDM_ADD' is requested using `%tldm_add'. + + * `R_SPARC_TLS_LDM_CALL' is requested using `%tldm_call'. + + * `R_SPARC_TLS_LDO_HIX22' is requested using `%tldo_hix22'. + + * `R_SPARC_TLS_LDO_LOX10' is requested using `%tldo_lox10'. + + * `R_SPARC_TLS_LDO_ADD' is requested using `%tldo_add'. + + * `R_SPARC_TLS_IE_HI22' is requested using `%tie_hi22'. + + * `R_SPARC_TLS_IE_LO10' is requested using `%tie_lo10'. + + * `R_SPARC_TLS_IE_LD' is requested using `%tie_ld'. + + * `R_SPARC_TLS_IE_LDX' is requested using `%tie_ldx'. + + * `R_SPARC_TLS_IE_ADD' is requested using `%tie_add'. + + * `R_SPARC_TLS_LE_HIX22' is requested using `%tle_hix22'. + + * `R_SPARC_TLS_LE_LOX10' is requested using `%tle_lox10'. + + Here are some example TLS model sequences. + + First, General Dynamic: + + sethi %tgd_hi22(symbol), %l1 + add %l1, %tgd_lo10(symbol), %l1 + add %l7, %l1, %o0, %tgd_add(symbol) + call __tls_get_addr, %tgd_call(symbol) + nop + + Local Dynamic: + + sethi %tldm_hi22(symbol), %l1 + add %l1, %tldm_lo10(symbol), %l1 + add %l7, %l1, %o0, %tldm_add(symbol) + call __tls_get_addr, %tldm_call(symbol) + nop + + sethi %tldo_hix22(symbol), %l1 + xor %l1, %tldo_lox10(symbol), %l1 + add %o0, %l1, %l1, %tldo_add(symbol) + + Initial Exec: + + sethi %tie_hi22(symbol), %l1 + add %l1, %tie_lo10(symbol), %l1 + ld [%l7 + %l1], %o0, %tie_ld(symbol) + add %g7, %o0, %o0, %tie_add(symbol) + + sethi %tie_hi22(symbol), %l1 + add %l1, %tie_lo10(symbol), %l1 + ldx [%l7 + %l1], %o0, %tie_ldx(symbol) + add %g7, %o0, %o0, %tie_add(symbol) + + And finally, Local Exec: + + sethi %tle_hix22(symbol), %l1 + add %l1, %tle_lox10(symbol), %l1 + add %g7, %l1, %l1 + + When assembling for 64-bit, and a secondary constant addend is +specified in an address expression that would normally generate an +`R_SPARC_LO10' relocation, the assembler will emit an `R_SPARC_OLO10' +instead. + + +File: as.info, Node: Sparc-Size-Translations, Prev: Sparc-Relocs, Up: Sparc-Syntax + +9.34.3.5 Size Translations +.......................... + +Often it is desirable to write code in an operand size agnostic manner. +`as' provides support for this via operand size opcode translations. +Translations are supported for loads, stores, shifts, compare-and-swap +atomics, and the `clr' synthetic instruction. + + If generating 32-bit code, `as' will generate the 32-bit opcode. +Whereas if 64-bit code is being generated, the 64-bit opcode will be +emitted. For example `ldn' will be transformed into `ld' for 32-bit +code and `ldx' for 64-bit code. + + Here is an example meant to demonstrate all the supported opcode +translations: + + ldn [%o0], %o1 + ldna [%o0] %asi, %o2 + stn %o1, [%o0] + stna %o2, [%o0] %asi + slln %o3, 3, %o3 + srln %o4, 8, %o4 + sran %o5, 12, %o5 + casn [%o0], %o1, %o2 + casna [%o0] %asi, %o1, %o2 + clrn %g1 + + In 32-bit mode `as' will emit: + + ld [%o0], %o1 + lda [%o0] %asi, %o2 + st %o1, [%o0] + sta %o2, [%o0] %asi + sll %o3, 3, %o3 + srl %o4, 8, %o4 + sra %o5, 12, %o5 + cas [%o0], %o1, %o2 + casa [%o0] %asi, %o1, %o2 + clr %g1 + + And in 64-bit mode `as' will emit: + + ldx [%o0], %o1 + ldxa [%o0] %asi, %o2 + stx %o1, [%o0] + stxa %o2, [%o0] %asi + sllx %o3, 3, %o3 + srlx %o4, 8, %o4 + srax %o5, 12, %o5 + casx [%o0], %o1, %o2 + casxa [%o0] %asi, %o1, %o2 + clrx %g1 + + Finally, the `.nword' translating directive is supported as well. +It is documented in the section on Sparc machine directives. + + +File: as.info, Node: Sparc-Float, Next: Sparc-Directives, Prev: Sparc-Syntax, Up: Sparc-Dependent + +9.34.4 Floating Point +--------------------- + +The Sparc uses IEEE floating-point numbers. + + +File: as.info, Node: Sparc-Directives, Prev: Sparc-Float, Up: Sparc-Dependent + +9.34.5 Sparc Machine Directives +------------------------------- + +The Sparc version of `as' supports the following additional machine +directives: + +`.align' + This must be followed by the desired alignment in bytes. + +`.common' + This must be followed by a symbol name, a positive number, and + `"bss"'. This behaves somewhat like `.comm', but the syntax is + different. + +`.half' + This is functionally identical to `.short'. + +`.nword' + On the Sparc, the `.nword' directive produces native word sized + value, ie. if assembling with -32 it is equivalent to `.word', if + assembling with -64 it is equivalent to `.xword'. + +`.proc' + This directive is ignored. Any text following it on the same line + is also ignored. + +`.register' + This directive declares use of a global application or system + register. It must be followed by a register name %g2, %g3, %g6 or + %g7, comma and the symbol name for that register. If symbol name + is `#scratch', it is a scratch register, if it is `#ignore', it + just suppresses any errors about using undeclared global register, + but does not emit any information about it into the object file. + This can be useful e.g. if you save the register before use and + restore it after. + +`.reserve' + This must be followed by a symbol name, a positive number, and + `"bss"'. This behaves somewhat like `.lcomm', but the syntax is + different. + +`.seg' + This must be followed by `"text"', `"data"', or `"data1"'. It + behaves like `.text', `.data', or `.data 1'. + +`.skip' + This is functionally identical to the `.space' directive. + +`.word' + On the Sparc, the `.word' directive produces 32 bit values, + instead of the 16 bit values it produces on many other machines. + +`.xword' + On the Sparc V9 processor, the `.xword' directive produces 64 bit + values. + + +File: as.info, Node: TIC54X-Dependent, Next: V850-Dependent, Prev: Sparc-Dependent, Up: Machine Dependencies + +9.35 TIC54X Dependent Features +============================== + +* Menu: + +* TIC54X-Opts:: Command-line Options +* TIC54X-Block:: Blocking +* TIC54X-Env:: Environment Settings +* TIC54X-Constants:: Constants Syntax +* TIC54X-Subsyms:: String Substitution +* TIC54X-Locals:: Local Label Syntax +* TIC54X-Builtins:: Builtin Assembler Math Functions +* TIC54X-Ext:: Extended Addressing Support +* TIC54X-Directives:: Directives +* TIC54X-Macros:: Macro Features +* TIC54X-MMRegs:: Memory-mapped Registers + + +File: as.info, Node: TIC54X-Opts, Next: TIC54X-Block, Up: TIC54X-Dependent + +9.35.1 Options +-------------- + +The TMS320C54X version of `as' has a few machine-dependent options. + + You can use the `-mfar-mode' option to enable extended addressing +mode. All addresses will be assumed to be > 16 bits, and the +appropriate relocation types will be used. This option is equivalent +to using the `.far_mode' directive in the assembly code. If you do not +use the `-mfar-mode' option, all references will be assumed to be 16 +bits. This option may be abbreviated to `-mf'. + + You can use the `-mcpu' option to specify a particular CPU. This +option is equivalent to using the `.version' directive in the assembly +code. For recognized CPU codes, see *Note `.version': +TIC54X-Directives. The default CPU version is `542'. + + You can use the `-merrors-to-file' option to redirect error output +to a file (this provided for those deficient environments which don't +provide adequate output redirection). This option may be abbreviated to +`-me'. + + +File: as.info, Node: TIC54X-Block, Next: TIC54X-Env, Prev: TIC54X-Opts, Up: TIC54X-Dependent + +9.35.2 Blocking +--------------- + +A blocked section or memory block is guaranteed not to cross the +blocking boundary (usually a page, or 128 words) if it is smaller than +the blocking size, or to start on a page boundary if it is larger than +the blocking size. + + +File: as.info, Node: TIC54X-Env, Next: TIC54X-Constants, Prev: TIC54X-Block, Up: TIC54X-Dependent + +9.35.3 Environment Settings +--------------------------- + +`C54XDSP_DIR' and `A_DIR' are semicolon-separated paths which are added +to the list of directories normally searched for source and include +files. `C54XDSP_DIR' will override `A_DIR'. + + +File: as.info, Node: TIC54X-Constants, Next: TIC54X-Subsyms, Prev: TIC54X-Env, Up: TIC54X-Dependent + +9.35.4 Constants Syntax +----------------------- + +The TIC54X version of `as' allows the following additional constant +formats, using a suffix to indicate the radix: + + Binary `000000B, 011000b' + Octal `10Q, 224q' + Hexadecimal `45h, 0FH' + + +File: as.info, Node: TIC54X-Subsyms, Next: TIC54X-Locals, Prev: TIC54X-Constants, Up: TIC54X-Dependent + +9.35.5 String Substitution +-------------------------- + +A subset of allowable symbols (which we'll call subsyms) may be assigned +arbitrary string values. This is roughly equivalent to C preprocessor +#define macros. When `as' encounters one of these symbols, the symbol +is replaced in the input stream by its string value. Subsym names +*must* begin with a letter. + + Subsyms may be defined using the `.asg' and `.eval' directives +(*Note `.asg': TIC54X-Directives, *Note `.eval': TIC54X-Directives. + + Expansion is recursive until a previously encountered symbol is +seen, at which point substitution stops. + + In this example, x is replaced with SYM2; SYM2 is replaced with +SYM1, and SYM1 is replaced with x. At this point, x has already been +encountered and the substitution stops. + + .asg "x",SYM1 + .asg "SYM1",SYM2 + .asg "SYM2",x + add x,a ; final code assembled is "add x, a" + + Macro parameters are converted to subsyms; a side effect of this is +the normal `as' '\ARG' dereferencing syntax is unnecessary. Subsyms +defined within a macro will have global scope, unless the `.var' +directive is used to identify the subsym as a local macro variable +*note `.var': TIC54X-Directives. + + Substitution may be forced in situations where replacement might be +ambiguous by placing colons on either side of the subsym. The following +code: + + .eval "10",x + LAB:X: add #x, a + + When assembled becomes: + + LAB10 add #10, a + + Smaller parts of the string assigned to a subsym may be accessed with +the following syntax: + +``:SYMBOL(CHAR_INDEX):'' + Evaluates to a single-character string, the character at + CHAR_INDEX. + +``:SYMBOL(START,LENGTH):'' + Evaluates to a substring of SYMBOL beginning at START with length + LENGTH. + + +File: as.info, Node: TIC54X-Locals, Next: TIC54X-Builtins, Prev: TIC54X-Subsyms, Up: TIC54X-Dependent + +9.35.6 Local Labels +------------------- + +Local labels may be defined in two ways: + + * $N, where N is a decimal number between 0 and 9 + + * LABEL?, where LABEL is any legal symbol name. + + Local labels thus defined may be redefined or automatically +generated. The scope of a local label is based on when it may be +undefined or reset. This happens when one of the following situations +is encountered: + + * .newblock directive *note `.newblock': TIC54X-Directives. + + * The current section is changed (.sect, .text, or .data) + + * Entering or leaving an included file + + * The macro scope where the label was defined is exited + + +File: as.info, Node: TIC54X-Builtins, Next: TIC54X-Ext, Prev: TIC54X-Locals, Up: TIC54X-Dependent + +9.35.7 Math Builtins +-------------------- + +The following built-in functions may be used to generate a +floating-point value. All return a floating-point value except `$cvi', +`$int', and `$sgn', which return an integer value. + +``$acos(EXPR)'' + Returns the floating point arccosine of EXPR. + +``$asin(EXPR)'' + Returns the floating point arcsine of EXPR. + +``$atan(EXPR)'' + Returns the floating point arctangent of EXPR. + +``$atan2(EXPR1,EXPR2)'' + Returns the floating point arctangent of EXPR1 / EXPR2. + +``$ceil(EXPR)'' + Returns the smallest integer not less than EXPR as floating point. + +``$cosh(EXPR)'' + Returns the floating point hyperbolic cosine of EXPR. + +``$cos(EXPR)'' + Returns the floating point cosine of EXPR. + +``$cvf(EXPR)'' + Returns the integer value EXPR converted to floating-point. + +``$cvi(EXPR)'' + Returns the floating point value EXPR converted to integer. + +``$exp(EXPR)'' + Returns the floating point value e ^ EXPR. + +``$fabs(EXPR)'' + Returns the floating point absolute value of EXPR. + +``$floor(EXPR)'' + Returns the largest integer that is not greater than EXPR as + floating point. + +``$fmod(EXPR1,EXPR2)'' + Returns the floating point remainder of EXPR1 / EXPR2. + +``$int(EXPR)'' + Returns 1 if EXPR evaluates to an integer, zero otherwise. + +``$ldexp(EXPR1,EXPR2)'' + Returns the floating point value EXPR1 * 2 ^ EXPR2. + +``$log10(EXPR)'' + Returns the base 10 logarithm of EXPR. + +``$log(EXPR)'' + Returns the natural logarithm of EXPR. + +``$max(EXPR1,EXPR2)'' + Returns the floating point maximum of EXPR1 and EXPR2. + +``$min(EXPR1,EXPR2)'' + Returns the floating point minimum of EXPR1 and EXPR2. + +``$pow(EXPR1,EXPR2)'' + Returns the floating point value EXPR1 ^ EXPR2. + +``$round(EXPR)'' + Returns the nearest integer to EXPR as a floating point number. + +``$sgn(EXPR)'' + Returns -1, 0, or 1 based on the sign of EXPR. + +``$sin(EXPR)'' + Returns the floating point sine of EXPR. + +``$sinh(EXPR)'' + Returns the floating point hyperbolic sine of EXPR. + +``$sqrt(EXPR)'' + Returns the floating point square root of EXPR. + +``$tan(EXPR)'' + Returns the floating point tangent of EXPR. + +``$tanh(EXPR)'' + Returns the floating point hyperbolic tangent of EXPR. + +``$trunc(EXPR)'' + Returns the integer value of EXPR truncated towards zero as + floating point. + + + +File: as.info, Node: TIC54X-Ext, Next: TIC54X-Directives, Prev: TIC54X-Builtins, Up: TIC54X-Dependent + +9.35.8 Extended Addressing +-------------------------- + +The `LDX' pseudo-op is provided for loading the extended addressing bits +of a label or address. For example, if an address `_label' resides in +extended program memory, the value of `_label' may be loaded as follows: + ldx #_label,16,a ; loads extended bits of _label + or #_label,a ; loads lower 16 bits of _label + bacc a ; full address is in accumulator A + + +File: as.info, Node: TIC54X-Directives, Next: TIC54X-Macros, Prev: TIC54X-Ext, Up: TIC54X-Dependent + +9.35.9 Directives +----------------- + +`.align [SIZE]' +`.even' + Align the section program counter on the next boundary, based on + SIZE. SIZE may be any power of 2. `.even' is equivalent to + `.align' with a SIZE of 2. + `1' + Align SPC to word boundary + + `2' + Align SPC to longword boundary (same as .even) + + `128' + Align SPC to page boundary + +`.asg STRING, NAME' + Assign NAME the string STRING. String replacement is performed on + STRING before assignment. + +`.eval STRING, NAME' + Evaluate the contents of string STRING and assign the result as a + string to the subsym NAME. String replacement is performed on + STRING before assignment. + +`.bss SYMBOL, SIZE [, [BLOCKING_FLAG] [,ALIGNMENT_FLAG]]' + Reserve space for SYMBOL in the .bss section. SIZE is in words. + If present, BLOCKING_FLAG indicates the allocated space should be + aligned on a page boundary if it would otherwise cross a page + boundary. If present, ALIGNMENT_FLAG causes the assembler to + allocate SIZE on a long word boundary. + +`.byte VALUE [,...,VALUE_N]' +`.ubyte VALUE [,...,VALUE_N]' +`.char VALUE [,...,VALUE_N]' +`.uchar VALUE [,...,VALUE_N]' + Place one or more bytes into consecutive words of the current + section. The upper 8 bits of each word is zero-filled. If a + label is used, it points to the word allocated for the first byte + encountered. + +`.clink ["SECTION_NAME"]' + Set STYP_CLINK flag for this section, which indicates to the + linker that if no symbols from this section are referenced, the + section should not be included in the link. If SECTION_NAME is + omitted, the current section is used. + +`.c_mode' + TBD. + +`.copy "FILENAME" | FILENAME' +`.include "FILENAME" | FILENAME' + Read source statements from FILENAME. The normal include search + path is used. Normally .copy will cause statements from the + included file to be printed in the assembly listing and .include + will not, but this distinction is not currently implemented. + +`.data' + Begin assembling code into the .data section. + +`.double VALUE [,...,VALUE_N]' +`.ldouble VALUE [,...,VALUE_N]' +`.float VALUE [,...,VALUE_N]' +`.xfloat VALUE [,...,VALUE_N]' + Place an IEEE single-precision floating-point representation of + one or more floating-point values into the current section. All + but `.xfloat' align the result on a longword boundary. Values are + stored most-significant word first. + +`.drlist' +`.drnolist' + Control printing of directives to the listing file. Ignored. + +`.emsg STRING' +`.mmsg STRING' +`.wmsg STRING' + Emit a user-defined error, message, or warning, respectively. + +`.far_mode' + Use extended addressing when assembling statements. This should + appear only once per file, and is equivalent to the -mfar-mode + option *note `-mfar-mode': TIC54X-Opts. + +`.fclist' +`.fcnolist' + Control printing of false conditional blocks to the listing file. + +`.field VALUE [,SIZE]' + Initialize a bitfield of SIZE bits in the current section. If + VALUE is relocatable, then SIZE must be 16. SIZE defaults to 16 + bits. If VALUE does not fit into SIZE bits, the value will be + truncated. Successive `.field' directives will pack starting at + the current word, filling the most significant bits first, and + aligning to the start of the next word if the field size does not + fit into the space remaining in the current word. A `.align' + directive with an operand of 1 will force the next `.field' + directive to begin packing into a new word. If a label is used, it + points to the word that contains the specified field. + +`.global SYMBOL [,...,SYMBOL_N]' +`.def SYMBOL [,...,SYMBOL_N]' +`.ref SYMBOL [,...,SYMBOL_N]' + `.def' nominally identifies a symbol defined in the current file + and available to other files. `.ref' identifies a symbol used in + the current file but defined elsewhere. Both map to the standard + `.global' directive. + +`.half VALUE [,...,VALUE_N]' +`.uhalf VALUE [,...,VALUE_N]' +`.short VALUE [,...,VALUE_N]' +`.ushort VALUE [,...,VALUE_N]' +`.int VALUE [,...,VALUE_N]' +`.uint VALUE [,...,VALUE_N]' +`.word VALUE [,...,VALUE_N]' +`.uword VALUE [,...,VALUE_N]' + Place one or more values into consecutive words of the current + section. If a label is used, it points to the word allocated for + the first value encountered. + +`.label SYMBOL' + Define a special SYMBOL to refer to the load time address of the + current section program counter. + +`.length' +`.width' + Set the page length and width of the output listing file. Ignored. + +`.list' +`.nolist' + Control whether the source listing is printed. Ignored. + +`.long VALUE [,...,VALUE_N]' +`.ulong VALUE [,...,VALUE_N]' +`.xlong VALUE [,...,VALUE_N]' + Place one or more 32-bit values into consecutive words in the + current section. The most significant word is stored first. + `.long' and `.ulong' align the result on a longword boundary; + `xlong' does not. + +`.loop [COUNT]' +`.break [CONDITION]' +`.endloop' + Repeatedly assemble a block of code. `.loop' begins the block, and + `.endloop' marks its termination. COUNT defaults to 1024, and + indicates the number of times the block should be repeated. + `.break' terminates the loop so that assembly begins after the + `.endloop' directive. The optional CONDITION will cause the loop + to terminate only if it evaluates to zero. + +`MACRO_NAME .macro [PARAM1][,...PARAM_N]' +`[.mexit]' +`.endm' + See the section on macros for more explanation (*Note + TIC54X-Macros::. + +`.mlib "FILENAME" | FILENAME' + Load the macro library FILENAME. FILENAME must be an archived + library (BFD ar-compatible) of text files, expected to contain + only macro definitions. The standard include search path is used. + +`.mlist' + +`.mnolist' + Control whether to include macro and loop block expansions in the + listing output. Ignored. + +`.mmregs' + Define global symbolic names for the 'c54x registers. Supposedly + equivalent to executing `.set' directives for each register with + its memory-mapped value, but in reality is provided only for + compatibility and does nothing. + +`.newblock' + This directive resets any TIC54X local labels currently defined. + Normal `as' local labels are unaffected. + +`.option OPTION_LIST' + Set listing options. Ignored. + +`.sblock "SECTION_NAME" | SECTION_NAME [,"NAME_N" | NAME_N]' + Designate SECTION_NAME for blocking. Blocking guarantees that a + section will start on a page boundary (128 words) if it would + otherwise cross a page boundary. Only initialized sections may be + designated with this directive. See also *Note TIC54X-Block::. + +`.sect "SECTION_NAME"' + Define a named initialized section and make it the current section. + +`SYMBOL .set "VALUE"' +`SYMBOL .equ "VALUE"' + Equate a constant VALUE to a SYMBOL, which is placed in the symbol + table. SYMBOL may not be previously defined. + +`.space SIZE_IN_BITS' +`.bes SIZE_IN_BITS' + Reserve the given number of bits in the current section and + zero-fill them. If a label is used with `.space', it points to the + *first* word reserved. With `.bes', the label points to the + *last* word reserved. + +`.sslist' +`.ssnolist' + Controls the inclusion of subsym replacement in the listing + output. Ignored. + +`.string "STRING" [,...,"STRING_N"]' +`.pstring "STRING" [,...,"STRING_N"]' + Place 8-bit characters from STRING into the current section. + `.string' zero-fills the upper 8 bits of each word, while + `.pstring' puts two characters into each word, filling the + most-significant bits first. Unused space is zero-filled. If a + label is used, it points to the first word initialized. + +`[STAG] .struct [OFFSET]' +`[NAME_1] element [COUNT_1]' +`[NAME_2] element [COUNT_2]' +`[TNAME] .tag STAGX [TCOUNT]' +`...' +`[NAME_N] element [COUNT_N]' +`[SSIZE] .endstruct' +`LABEL .tag [STAG]' + Assign symbolic offsets to the elements of a structure. STAG + defines a symbol to use to reference the structure. OFFSET + indicates a starting value to use for the first element + encountered; otherwise it defaults to zero. Each element can have + a named offset, NAME, which is a symbol assigned the value of the + element's offset into the structure. If STAG is missing, these + become global symbols. COUNT adjusts the offset that many times, + as if `element' were an array. `element' may be one of `.byte', + `.word', `.long', `.float', or any equivalent of those, and the + structure offset is adjusted accordingly. `.field' and `.string' + are also allowed; the size of `.field' is one bit, and `.string' + is considered to be one word in size. Only element descriptors, + structure/union tags, `.align' and conditional assembly directives + are allowed within `.struct'/`.endstruct'. `.align' aligns member + offsets to word boundaries only. SSIZE, if provided, will always + be assigned the size of the structure. + + The `.tag' directive, in addition to being used to define a + structure/union element within a structure, may be used to apply a + structure to a symbol. Once applied to LABEL, the individual + structure elements may be applied to LABEL to produce the desired + offsets using LABEL as the structure base. + +`.tab' + Set the tab size in the output listing. Ignored. + +`[UTAG] .union' +`[NAME_1] element [COUNT_1]' +`[NAME_2] element [COUNT_2]' +`[TNAME] .tag UTAGX[,TCOUNT]' +`...' +`[NAME_N] element [COUNT_N]' +`[USIZE] .endstruct' +`LABEL .tag [UTAG]' + Similar to `.struct', but the offset after each element is reset to + zero, and the USIZE is set to the maximum of all defined elements. + Starting offset for the union is always zero. + +`[SYMBOL] .usect "SECTION_NAME", SIZE, [,[BLOCKING_FLAG] [,ALIGNMENT_FLAG]]' + Reserve space for variables in a named, uninitialized section + (similar to .bss). `.usect' allows definitions sections + independent of .bss. SYMBOL points to the first location reserved + by this allocation. The symbol may be used as a variable name. + SIZE is the allocated size in words. BLOCKING_FLAG indicates + whether to block this section on a page boundary (128 words) + (*note TIC54X-Block::). ALIGNMENT FLAG indicates whether the + section should be longword-aligned. + +`.var SYM[,..., SYM_N]' + Define a subsym to be a local variable within a macro. See *Note + TIC54X-Macros::. + +`.version VERSION' + Set which processor to build instructions for. Though the + following values are accepted, the op is ignored. + `541' + `542' + `543' + `545' + `545LP' + `546LP' + `548' + `549' + + +File: as.info, Node: TIC54X-Macros, Next: TIC54X-MMRegs, Prev: TIC54X-Directives, Up: TIC54X-Dependent + +9.35.10 Macros +-------------- + +Macros do not require explicit dereferencing of arguments (i.e., \ARG). + + During macro expansion, the macro parameters are converted to +subsyms. If the number of arguments passed the macro invocation +exceeds the number of parameters defined, the last parameter is +assigned the string equivalent of all remaining arguments. If fewer +arguments are given than parameters, the missing parameters are +assigned empty strings. To include a comma in an argument, you must +enclose the argument in quotes. + + The following built-in subsym functions allow examination of the +string value of subsyms (or ordinary strings). The arguments are +strings unless otherwise indicated (subsyms passed as args will be +replaced by the strings they represent). +``$symlen(STR)'' + Returns the length of STR. + +``$symcmp(STR1,STR2)'' + Returns 0 if STR1 == STR2, non-zero otherwise. + +``$firstch(STR,CH)'' + Returns index of the first occurrence of character constant CH in + STR. + +``$lastch(STR,CH)'' + Returns index of the last occurrence of character constant CH in + STR. + +``$isdefed(SYMBOL)'' + Returns zero if the symbol SYMBOL is not in the symbol table, + non-zero otherwise. + +``$ismember(SYMBOL,LIST)'' + Assign the first member of comma-separated string LIST to SYMBOL; + LIST is reassigned the remainder of the list. Returns zero if + LIST is a null string. Both arguments must be subsyms. + +``$iscons(EXPR)'' + Returns 1 if string EXPR is binary, 2 if octal, 3 if hexadecimal, + 4 if a character, 5 if decimal, and zero if not an integer. + +``$isname(NAME)'' + Returns 1 if NAME is a valid symbol name, zero otherwise. + +``$isreg(REG)'' + Returns 1 if REG is a valid predefined register name (AR0-AR7 + only). + +``$structsz(STAG)'' + Returns the size of the structure or union represented by STAG. + +``$structacc(STAG)'' + Returns the reference point of the structure or union represented + by STAG. Always returns zero. + + + +File: as.info, Node: TIC54X-MMRegs, Prev: TIC54X-Macros, Up: TIC54X-Dependent + +9.35.11 Memory-mapped Registers +------------------------------- + +The following symbols are recognized as memory-mapped registers: + + + +File: as.info, Node: Z80-Dependent, Next: Z8000-Dependent, Prev: Xtensa-Dependent, Up: Machine Dependencies + +9.36 Z80 Dependent Features +=========================== + +* Menu: + +* Z80 Options:: Options +* Z80 Syntax:: Syntax +* Z80 Floating Point:: Floating Point +* Z80 Directives:: Z80 Machine Directives +* Z80 Opcodes:: Opcodes + + +File: as.info, Node: Z80 Options, Next: Z80 Syntax, Up: Z80-Dependent + +9.36.1 Options +-------------- + +The Zilog Z80 and Ascii R800 version of `as' have a few machine +dependent options. +`-z80' + Produce code for the Z80 processor. There are additional options to + request warnings and error messages for undocumented instructions. + +`-ignore-undocumented-instructions' +`-Wnud' + Silently assemble undocumented Z80-instructions that have been + adopted as documented R800-instructions. + +`-ignore-unportable-instructions' +`-Wnup' + Silently assemble all undocumented Z80-instructions. + +`-warn-undocumented-instructions' +`-Wud' + Issue warnings for undocumented Z80-instructions that work on + R800, do not assemble other undocumented instructions without + warning. + +`-warn-unportable-instructions' +`-Wup' + Issue warnings for other undocumented Z80-instructions, do not + treat any undocumented instructions as errors. + +`-forbid-undocumented-instructions' +`-Fud' + Treat all undocumented z80-instructions as errors. + +`-forbid-unportable-instructions' +`-Fup' + Treat undocumented z80-instructions that do not work on R800 as + errors. + +`-r800' + Produce code for the R800 processor. The assembler does not support + undocumented instructions for the R800. In line with common + practice, `as' uses Z80 instruction names for the R800 processor, + as far as they exist. + + +File: as.info, Node: Z80 Syntax, Next: Z80 Floating Point, Prev: Z80 Options, Up: Z80-Dependent + +9.36.2 Syntax +------------- + +The assembler syntax closely follows the 'Z80 family CPU User Manual' by +Zilog. In expressions a single `=' may be used as "is equal to" +comparison operator. + + Suffices can be used to indicate the radix of integer constants; `H' +or `h' for hexadecimal, `D' or `d' for decimal, `Q', `O', `q' or `o' +for octal, and `B' for binary. + + The suffix `b' denotes a backreference to local label. + +* Menu: + +* Z80-Chars:: Special Characters +* Z80-Regs:: Register Names +* Z80-Case:: Case Sensitivity + + +File: as.info, Node: Z80-Chars, Next: Z80-Regs, Up: Z80 Syntax + +9.36.2.1 Special Characters +........................... + +The semicolon `;' is the line comment character; + + The dollar sign `$' can be used as a prefix for hexadecimal numbers +and as a symbol denoting the current location counter. + + A backslash `\' is an ordinary character for the Z80 assembler. + + The single quote `'' must be followed by a closing quote. If there +is one character in between, it is a character constant, otherwise it is +a string constant. + + +File: as.info, Node: Z80-Regs, Next: Z80-Case, Prev: Z80-Chars, Up: Z80 Syntax + +9.36.2.2 Register Names +....................... + +The registers are referred to with the letters assigned to them by +Zilog. In addition `as' recognizes `ixl' and `ixh' as the least and +most significant octet in `ix', and similarly `iyl' and `iyh' as parts +of `iy'. + + +File: as.info, Node: Z80-Case, Prev: Z80-Regs, Up: Z80 Syntax + +9.36.2.3 Case Sensitivity +......................... + +Upper and lower case are equivalent in register names, opcodes, +condition codes and assembler directives. The case of letters is +significant in labels and symbol names. The case is also important to +distinguish the suffix `b' for a backward reference to a local label +from the suffix `B' for a number in binary notation. + + +File: as.info, Node: Z80 Floating Point, Next: Z80 Directives, Prev: Z80 Syntax, Up: Z80-Dependent + +9.36.3 Floating Point +--------------------- + +Floating-point numbers are not supported. + + +File: as.info, Node: Z80 Directives, Next: Z80 Opcodes, Prev: Z80 Floating Point, Up: Z80-Dependent + +9.36.4 Z80 Assembler Directives +------------------------------- + +`as' for the Z80 supports some additional directives for compatibility +with other assemblers. + + These are the additional directives in `as' for the Z80: + +`db EXPRESSION|STRING[,EXPRESSION|STRING...]' +`defb EXPRESSION|STRING[,EXPRESSION|STRING...]' + For each STRING the characters are copied to the object file, for + each other EXPRESSION the value is stored in one byte. A warning + is issued in case of an overflow. + +`dw EXPRESSION[,EXPRESSION...]' +`defw EXPRESSION[,EXPRESSION...]' + For each EXPRESSION the value is stored in two bytes, ignoring + overflow. + +`d24 EXPRESSION[,EXPRESSION...]' +`def24 EXPRESSION[,EXPRESSION...]' + For each EXPRESSION the value is stored in three bytes, ignoring + overflow. + +`d32 EXPRESSION[,EXPRESSION...]' +`def32 EXPRESSION[,EXPRESSION...]' + For each EXPRESSION the value is stored in four bytes, ignoring + overflow. + +`ds COUNT[, VALUE]' +`defs COUNT[, VALUE]' + Fill COUNT bytes in the object file with VALUE, if VALUE is + omitted it defaults to zero. + +`SYMBOL equ EXPRESSION' +`SYMBOL defl EXPRESSION' + These directives set the value of SYMBOL to EXPRESSION. If `equ' + is used, it is an error if SYMBOL is already defined. Symbols + defined with `equ' are not protected from redefinition. + +`set' + This is a normal instruction on Z80, and not an assembler + directive. + +`psect NAME' + A synonym for *Note Section::, no second argument should be given. + + + +File: as.info, Node: Z80 Opcodes, Prev: Z80 Directives, Up: Z80-Dependent + +9.36.5 Opcodes +-------------- + +In line with common practice, Z80 mnemonics are used for both the Z80 +and the R800. + + In many instructions it is possible to use one of the half index +registers (`ixl',`ixh',`iyl',`iyh') in stead of an 8-bit general +purpose register. This yields instructions that are documented on the +R800 and undocumented on the Z80. Similarly `in f,(c)' is documented +on the R800 and undocumented on the Z80. + + The assembler also supports the following undocumented +Z80-instructions, that have not been adopted in the R800 instruction +set: +`out (c),0' + Sends zero to the port pointed to by register c. + +`sli M' + Equivalent to `M = (M<<1)+1', the operand M can be any operand + that is valid for `sla'. One can use `sll' as a synonym for `sli'. + +`OP (ix+D), R' + This is equivalent to + + ld R, (ix+D) + OPC R + ld (ix+D), R + + The operation `OPC' may be any of `res B,', `set B,', `rl', `rlc', + `rr', `rrc', `sla', `sli', `sra' and `srl', and the register `R' + may be any of `a', `b', `c', `d', `e', `h' and `l'. + +`OPC (iy+D), R' + As above, but with `iy' instead of `ix'. + + The web site at `http://www.z80.info' is a good starting place to +find more information on programming the Z80. + + +File: as.info, Node: Z8000-Dependent, Next: Vax-Dependent, Prev: Z80-Dependent, Up: Machine Dependencies + +9.37 Z8000 Dependent Features +============================= + + The Z8000 as supports both members of the Z8000 family: the +unsegmented Z8002, with 16 bit addresses, and the segmented Z8001 with +24 bit addresses. + + When the assembler is in unsegmented mode (specified with the +`unsegm' directive), an address takes up one word (16 bit) sized +register. When the assembler is in segmented mode (specified with the +`segm' directive), a 24-bit address takes up a long (32 bit) register. +*Note Assembler Directives for the Z8000: Z8000 Directives, for a list +of other Z8000 specific assembler directives. + +* Menu: + +* Z8000 Options:: Command-line options for the Z8000 +* Z8000 Syntax:: Assembler syntax for the Z8000 +* Z8000 Directives:: Special directives for the Z8000 +* Z8000 Opcodes:: Opcodes + + +File: as.info, Node: Z8000 Options, Next: Z8000 Syntax, Up: Z8000-Dependent + +9.37.1 Options +-------------- + +`-z8001' + Generate segmented code by default. + +`-z8002' + Generate unsegmented code by default. + + +File: as.info, Node: Z8000 Syntax, Next: Z8000 Directives, Prev: Z8000 Options, Up: Z8000-Dependent + +9.37.2 Syntax +------------- + +* Menu: + +* Z8000-Chars:: Special Characters +* Z8000-Regs:: Register Names +* Z8000-Addressing:: Addressing Modes + + +File: as.info, Node: Z8000-Chars, Next: Z8000-Regs, Up: Z8000 Syntax + +9.37.2.1 Special Characters +........................... + +`!' is the line comment character. + + You can use `;' instead of a newline to separate statements. + + +File: as.info, Node: Z8000-Regs, Next: Z8000-Addressing, Prev: Z8000-Chars, Up: Z8000 Syntax + +9.37.2.2 Register Names +....................... + +The Z8000 has sixteen 16 bit registers, numbered 0 to 15. You can refer +to different sized groups of registers by register number, with the +prefix `r' for 16 bit registers, `rr' for 32 bit registers and `rq' for +64 bit registers. You can also refer to the contents of the first +eight (of the sixteen 16 bit registers) by bytes. They are named `rlN' +and `rhN'. + +_byte registers_ + rl0 rh0 rl1 rh1 rl2 rh2 rl3 rh3 + rl4 rh4 rl5 rh5 rl6 rh6 rl7 rh7 + +_word registers_ + r0 r1 r2 r3 r4 r5 r6 r7 r8 r9 r10 r11 r12 r13 r14 r15 + +_long word registers_ + rr0 rr2 rr4 rr6 rr8 rr10 rr12 rr14 + +_quad word registers_ + rq0 rq4 rq8 rq12 + + +File: as.info, Node: Z8000-Addressing, Prev: Z8000-Regs, Up: Z8000 Syntax + +9.37.2.3 Addressing Modes +......................... + +as understands the following addressing modes for the Z8000: + +`rlN' +`rhN' +`rN' +`rrN' +`rqN' + Register direct: 8bit, 16bit, 32bit, and 64bit registers. + +`@rN' +`@rrN' + Indirect register: @rrN in segmented mode, @rN in unsegmented + mode. + +`ADDR' + Direct: the 16 bit or 24 bit address (depending on whether the + assembler is in segmented or unsegmented mode) of the operand is + in the instruction. + +`address(rN)' + Indexed: the 16 or 24 bit address is added to the 16 bit register + to produce the final address in memory of the operand. + +`rN(#IMM)' +`rrN(#IMM)' + Base Address: the 16 or 24 bit register is added to the 16 bit sign + extended immediate displacement to produce the final address in + memory of the operand. + +`rN(rM)' +`rrN(rM)' + Base Index: the 16 or 24 bit register rN or rrN is added to the + sign extended 16 bit index register rM to produce the final + address in memory of the operand. + +`#XX' + Immediate data XX. + + +File: as.info, Node: Z8000 Directives, Next: Z8000 Opcodes, Prev: Z8000 Syntax, Up: Z8000-Dependent + +9.37.3 Assembler Directives for the Z8000 +----------------------------------------- + +The Z8000 port of as includes additional assembler directives, for +compatibility with other Z8000 assemblers. These do not begin with `.' +(unlike the ordinary as directives). + +`segm' +`.z8001' + Generate code for the segmented Z8001. + +`unsegm' +`.z8002' + Generate code for the unsegmented Z8002. + +`name' + Synonym for `.file' + +`global' + Synonym for `.global' + +`wval' + Synonym for `.word' + +`lval' + Synonym for `.long' + +`bval' + Synonym for `.byte' + +`sval' + Assemble a string. `sval' expects one string literal, delimited by + single quotes. It assembles each byte of the string into + consecutive addresses. You can use the escape sequence `%XX' + (where XX represents a two-digit hexadecimal number) to represent + the character whose ASCII value is XX. Use this feature to + describe single quote and other characters that may not appear in + string literals as themselves. For example, the C statement + `char *a = "he said \"it's 50% off\"";' is represented in Z8000 + assembly language (shown with the assembler output in hex at the + left) as + + 68652073 sval 'he said %22it%27s 50%25 off%22%00' + 61696420 + 22697427 + 73203530 + 25206F66 + 662200 + +`rsect' + synonym for `.section' + +`block' + synonym for `.space' + +`even' + special case of `.align'; aligns output to even byte boundary. + + +File: as.info, Node: Z8000 Opcodes, Prev: Z8000 Directives, Up: Z8000-Dependent + +9.37.4 Opcodes +-------------- + +For detailed information on the Z8000 machine instruction set, see +`Z8000 Technical Manual'. + + The following table summarizes the opcodes and their arguments: + + rs 16 bit source register + rd 16 bit destination register + rbs 8 bit source register + rbd 8 bit destination register + rrs 32 bit source register + rrd 32 bit destination register + rqs 64 bit source register + rqd 64 bit destination register + addr 16/24 bit address + imm immediate data + + adc rd,rs clrb addr cpsir @rd,@rs,rr,cc + adcb rbd,rbs clrb addr(rd) cpsirb @rd,@rs,rr,cc + add rd,@rs clrb rbd dab rbd + add rd,addr com @rd dbjnz rbd,disp7 + add rd,addr(rs) com addr dec @rd,imm4m1 + add rd,imm16 com addr(rd) dec addr(rd),imm4m1 + add rd,rs com rd dec addr,imm4m1 + addb rbd,@rs comb @rd dec rd,imm4m1 + addb rbd,addr comb addr decb @rd,imm4m1 + addb rbd,addr(rs) comb addr(rd) decb addr(rd),imm4m1 + addb rbd,imm8 comb rbd decb addr,imm4m1 + addb rbd,rbs comflg flags decb rbd,imm4m1 + addl rrd,@rs cp @rd,imm16 di i2 + addl rrd,addr cp addr(rd),imm16 div rrd,@rs + addl rrd,addr(rs) cp addr,imm16 div rrd,addr + addl rrd,imm32 cp rd,@rs div rrd,addr(rs) + addl rrd,rrs cp rd,addr div rrd,imm16 + and rd,@rs cp rd,addr(rs) div rrd,rs + and rd,addr cp rd,imm16 divl rqd,@rs + and rd,addr(rs) cp rd,rs divl rqd,addr + and rd,imm16 cpb @rd,imm8 divl rqd,addr(rs) + and rd,rs cpb addr(rd),imm8 divl rqd,imm32 + andb rbd,@rs cpb addr,imm8 divl rqd,rrs + andb rbd,addr cpb rbd,@rs djnz rd,disp7 + andb rbd,addr(rs) cpb rbd,addr ei i2 + andb rbd,imm8 cpb rbd,addr(rs) ex rd,@rs + andb rbd,rbs cpb rbd,imm8 ex rd,addr + bit @rd,imm4 cpb rbd,rbs ex rd,addr(rs) + bit addr(rd),imm4 cpd rd,@rs,rr,cc ex rd,rs + bit addr,imm4 cpdb rbd,@rs,rr,cc exb rbd,@rs + bit rd,imm4 cpdr rd,@rs,rr,cc exb rbd,addr + bit rd,rs cpdrb rbd,@rs,rr,cc exb rbd,addr(rs) + bitb @rd,imm4 cpi rd,@rs,rr,cc exb rbd,rbs + bitb addr(rd),imm4 cpib rbd,@rs,rr,cc ext0e imm8 + bitb addr,imm4 cpir rd,@rs,rr,cc ext0f imm8 + bitb rbd,imm4 cpirb rbd,@rs,rr,cc ext8e imm8 + bitb rbd,rs cpl rrd,@rs ext8f imm8 + bpt cpl rrd,addr exts rrd + call @rd cpl rrd,addr(rs) extsb rd + call addr cpl rrd,imm32 extsl rqd + call addr(rd) cpl rrd,rrs halt + calr disp12 cpsd @rd,@rs,rr,cc in rd,@rs + clr @rd cpsdb @rd,@rs,rr,cc in rd,imm16 + clr addr cpsdr @rd,@rs,rr,cc inb rbd,@rs + clr addr(rd) cpsdrb @rd,@rs,rr,cc inb rbd,imm16 + clr rd cpsi @rd,@rs,rr,cc inc @rd,imm4m1 + clrb @rd cpsib @rd,@rs,rr,cc inc addr(rd),imm4m1 + inc addr,imm4m1 ldb rbd,rs(rx) mult rrd,addr(rs) + inc rd,imm4m1 ldb rd(imm16),rbs mult rrd,imm16 + incb @rd,imm4m1 ldb rd(rx),rbs mult rrd,rs + incb addr(rd),imm4m1 ldctl ctrl,rs multl rqd,@rs + incb addr,imm4m1 ldctl rd,ctrl multl rqd,addr + incb rbd,imm4m1 ldd @rs,@rd,rr multl rqd,addr(rs) + ind @rd,@rs,ra lddb @rs,@rd,rr multl rqd,imm32 + indb @rd,@rs,rba lddr @rs,@rd,rr multl rqd,rrs + inib @rd,@rs,ra lddrb @rs,@rd,rr neg @rd + inibr @rd,@rs,ra ldi @rd,@rs,rr neg addr + iret ldib @rd,@rs,rr neg addr(rd) + jp cc,@rd ldir @rd,@rs,rr neg rd + jp cc,addr ldirb @rd,@rs,rr negb @rd + jp cc,addr(rd) ldk rd,imm4 negb addr + jr cc,disp8 ldl @rd,rrs negb addr(rd) + ld @rd,imm16 ldl addr(rd),rrs negb rbd + ld @rd,rs ldl addr,rrs nop + ld addr(rd),imm16 ldl rd(imm16),rrs or rd,@rs + ld addr(rd),rs ldl rd(rx),rrs or rd,addr + ld addr,imm16 ldl rrd,@rs or rd,addr(rs) + ld addr,rs ldl rrd,addr or rd,imm16 + ld rd(imm16),rs ldl rrd,addr(rs) or rd,rs + ld rd(rx),rs ldl rrd,imm32 orb rbd,@rs + ld rd,@rs ldl rrd,rrs orb rbd,addr + ld rd,addr ldl rrd,rs(imm16) orb rbd,addr(rs) + ld rd,addr(rs) ldl rrd,rs(rx) orb rbd,imm8 + ld rd,imm16 ldm @rd,rs,n orb rbd,rbs + ld rd,rs ldm addr(rd),rs,n out @rd,rs + ld rd,rs(imm16) ldm addr,rs,n out imm16,rs + ld rd,rs(rx) ldm rd,@rs,n outb @rd,rbs + lda rd,addr ldm rd,addr(rs),n outb imm16,rbs + lda rd,addr(rs) ldm rd,addr,n outd @rd,@rs,ra + lda rd,rs(imm16) ldps @rs outdb @rd,@rs,rba + lda rd,rs(rx) ldps addr outib @rd,@rs,ra + ldar rd,disp16 ldps addr(rs) outibr @rd,@rs,ra + ldb @rd,imm8 ldr disp16,rs pop @rd,@rs + ldb @rd,rbs ldr rd,disp16 pop addr(rd),@rs + ldb addr(rd),imm8 ldrb disp16,rbs pop addr,@rs + ldb addr(rd),rbs ldrb rbd,disp16 pop rd,@rs + ldb addr,imm8 ldrl disp16,rrs popl @rd,@rs + ldb addr,rbs ldrl rrd,disp16 popl addr(rd),@rs + ldb rbd,@rs mbit popl addr,@rs + ldb rbd,addr mreq rd popl rrd,@rs + ldb rbd,addr(rs) mres push @rd,@rs + ldb rbd,imm8 mset push @rd,addr + ldb rbd,rbs mult rrd,@rs push @rd,addr(rs) + ldb rbd,rs(imm16) mult rrd,addr push @rd,imm16 + push @rd,rs set addr,imm4 subl rrd,imm32 + pushl @rd,@rs set rd,imm4 subl rrd,rrs + pushl @rd,addr set rd,rs tcc cc,rd + pushl @rd,addr(rs) setb @rd,imm4 tccb cc,rbd + pushl @rd,rrs setb addr(rd),imm4 test @rd + res @rd,imm4 setb addr,imm4 test addr + res addr(rd),imm4 setb rbd,imm4 test addr(rd) + res addr,imm4 setb rbd,rs test rd + res rd,imm4 setflg imm4 testb @rd + res rd,rs sinb rbd,imm16 testb addr + resb @rd,imm4 sinb rd,imm16 testb addr(rd) + resb addr(rd),imm4 sind @rd,@rs,ra testb rbd + resb addr,imm4 sindb @rd,@rs,rba testl @rd + resb rbd,imm4 sinib @rd,@rs,ra testl addr + resb rbd,rs sinibr @rd,@rs,ra testl addr(rd) + resflg imm4 sla rd,imm8 testl rrd + ret cc slab rbd,imm8 trdb @rd,@rs,rba + rl rd,imm1or2 slal rrd,imm8 trdrb @rd,@rs,rba + rlb rbd,imm1or2 sll rd,imm8 trib @rd,@rs,rbr + rlc rd,imm1or2 sllb rbd,imm8 trirb @rd,@rs,rbr + rlcb rbd,imm1or2 slll rrd,imm8 trtdrb @ra,@rb,rbr + rldb rbb,rba sout imm16,rs trtib @ra,@rb,rr + rr rd,imm1or2 soutb imm16,rbs trtirb @ra,@rb,rbr + rrb rbd,imm1or2 soutd @rd,@rs,ra trtrb @ra,@rb,rbr + rrc rd,imm1or2 soutdb @rd,@rs,rba tset @rd + rrcb rbd,imm1or2 soutib @rd,@rs,ra tset addr + rrdb rbb,rba soutibr @rd,@rs,ra tset addr(rd) + rsvd36 sra rd,imm8 tset rd + rsvd38 srab rbd,imm8 tsetb @rd + rsvd78 sral rrd,imm8 tsetb addr + rsvd7e srl rd,imm8 tsetb addr(rd) + rsvd9d srlb rbd,imm8 tsetb rbd + rsvd9f srll rrd,imm8 xor rd,@rs + rsvdb9 sub rd,@rs xor rd,addr + rsvdbf sub rd,addr xor rd,addr(rs) + sbc rd,rs sub rd,addr(rs) xor rd,imm16 + sbcb rbd,rbs sub rd,imm16 xor rd,rs + sc imm8 sub rd,rs xorb rbd,@rs + sda rd,rs subb rbd,@rs xorb rbd,addr + sdab rbd,rs subb rbd,addr xorb rbd,addr(rs) + sdal rrd,rs subb rbd,addr(rs) xorb rbd,imm8 + sdl rd,rs subb rbd,imm8 xorb rbd,rbs + sdlb rbd,rs subb rbd,rbs xorb rbd,rbs + sdll rrd,rs subl rrd,@rs + set @rd,imm4 subl rrd,addr + set addr(rd),imm4 subl rrd,addr(rs) + + +File: as.info, Node: Vax-Dependent, Prev: Z8000-Dependent, Up: Machine Dependencies + +9.38 VAX Dependent Features +=========================== + +* Menu: + +* VAX-Opts:: VAX Command-Line Options +* VAX-float:: VAX Floating Point +* VAX-directives:: Vax Machine Directives +* VAX-opcodes:: VAX Opcodes +* VAX-branch:: VAX Branch Improvement +* VAX-operands:: VAX Operands +* VAX-no:: Not Supported on VAX + + +File: as.info, Node: VAX-Opts, Next: VAX-float, Up: Vax-Dependent + +9.38.1 VAX Command-Line Options +------------------------------- + +The Vax version of `as' accepts any of the following options, gives a +warning message that the option was ignored and proceeds. These +options are for compatibility with scripts designed for other people's +assemblers. + +``-D' (Debug)' +``-S' (Symbol Table)' +``-T' (Token Trace)' + These are obsolete options used to debug old assemblers. + +``-d' (Displacement size for JUMPs)' + This option expects a number following the `-d'. Like options + that expect filenames, the number may immediately follow the `-d' + (old standard) or constitute the whole of the command line + argument that follows `-d' (GNU standard). + +``-V' (Virtualize Interpass Temporary File)' + Some other assemblers use a temporary file. This option commanded + them to keep the information in active memory rather than in a + disk file. `as' always does this, so this option is redundant. + +``-J' (JUMPify Longer Branches)' + Many 32-bit computers permit a variety of branch instructions to + do the same job. Some of these instructions are short (and fast) + but have a limited range; others are long (and slow) but can + branch anywhere in virtual memory. Often there are 3 flavors of + branch: short, medium and long. Some other assemblers would emit + short and medium branches, unless told by this option to emit + short and long branches. + +``-t' (Temporary File Directory)' + Some other assemblers may use a temporary file, and this option + takes a filename being the directory to site the temporary file. + Since `as' does not use a temporary disk file, this option makes + no difference. `-t' needs exactly one filename. + + The Vax version of the assembler accepts additional options when +compiled for VMS: + +`-h N' + External symbol or section (used for global variables) names are + not case sensitive on VAX/VMS and always mapped to upper case. + This is contrary to the C language definition which explicitly + distinguishes upper and lower case. To implement a standard + conforming C compiler, names must be changed (mapped) to preserve + the case information. The default mapping is to convert all lower + case characters to uppercase and adding an underscore followed by + a 6 digit hex value, representing a 24 digit binary value. The + one digits in the binary value represent which characters are + uppercase in the original symbol name. + + The `-h N' option determines how we map names. This takes several + values. No `-h' switch at all allows case hacking as described + above. A value of zero (`-h0') implies names should be upper + case, and inhibits the case hack. A value of 2 (`-h2') implies + names should be all lower case, with no case hack. A value of 3 + (`-h3') implies that case should be preserved. The value 1 is + unused. The `-H' option directs `as' to display every mapped + symbol during assembly. + + Symbols whose names include a dollar sign `$' are exceptions to the + general name mapping. These symbols are normally only used to + reference VMS library names. Such symbols are always mapped to + upper case. + +`-+' + The `-+' option causes `as' to truncate any symbol name larger + than 31 characters. The `-+' option also prevents some code + following the `_main' symbol normally added to make the object + file compatible with Vax-11 "C". + +`-1' + This option is ignored for backward compatibility with `as' + version 1.x. + +`-H' + The `-H' option causes `as' to print every symbol which was + changed by case mapping. + + +File: as.info, Node: VAX-float, Next: VAX-directives, Prev: VAX-Opts, Up: Vax-Dependent + +9.38.2 VAX Floating Point +------------------------- + +Conversion of flonums to floating point is correct, and compatible with +previous assemblers. Rounding is towards zero if the remainder is +exactly half the least significant bit. + + `D', `F', `G' and `H' floating point formats are understood. + + Immediate floating literals (_e.g._ `S`$6.9') are rendered +correctly. Again, rounding is towards zero in the boundary case. + + The `.float' directive produces `f' format numbers. The `.double' +directive produces `d' format numbers. + + +File: as.info, Node: VAX-directives, Next: VAX-opcodes, Prev: VAX-float, Up: Vax-Dependent + +9.38.3 Vax Machine Directives +----------------------------- + +The Vax version of the assembler supports four directives for +generating Vax floating point constants. They are described in the +table below. + +`.dfloat' + This expects zero or more flonums, separated by commas, and + assembles Vax `d' format 64-bit floating point constants. + +`.ffloat' + This expects zero or more flonums, separated by commas, and + assembles Vax `f' format 32-bit floating point constants. + +`.gfloat' + This expects zero or more flonums, separated by commas, and + assembles Vax `g' format 64-bit floating point constants. + +`.hfloat' + This expects zero or more flonums, separated by commas, and + assembles Vax `h' format 128-bit floating point constants. + + + +File: as.info, Node: VAX-opcodes, Next: VAX-branch, Prev: VAX-directives, Up: Vax-Dependent + +9.38.4 VAX Opcodes +------------------ + +All DEC mnemonics are supported. Beware that `case...' instructions +have exactly 3 operands. The dispatch table that follows the `case...' +instruction should be made with `.word' statements. This is compatible +with all unix assemblers we know of. + + +File: as.info, Node: VAX-branch, Next: VAX-operands, Prev: VAX-opcodes, Up: Vax-Dependent + +9.38.5 VAX Branch Improvement +----------------------------- + +Certain pseudo opcodes are permitted. They are for branch +instructions. They expand to the shortest branch instruction that +reaches the target. Generally these mnemonics are made by substituting +`j' for `b' at the start of a DEC mnemonic. This feature is included +both for compatibility and to help compilers. If you do not need this +feature, avoid these opcodes. Here are the mnemonics, and the code +they can expand into. + +`jbsb' + `Jsb' is already an instruction mnemonic, so we chose `jbsb'. + (byte displacement) + `bsbb ...' + + (word displacement) + `bsbw ...' + + (long displacement) + `jsb ...' + +`jbr' +`jr' + Unconditional branch. + (byte displacement) + `brb ...' + + (word displacement) + `brw ...' + + (long displacement) + `jmp ...' + +`jCOND' + COND may be any one of the conditional branches `neq', `nequ', + `eql', `eqlu', `gtr', `geq', `lss', `gtru', `lequ', `vc', `vs', + `gequ', `cc', `lssu', `cs'. COND may also be one of the bit tests + `bs', `bc', `bss', `bcs', `bsc', `bcc', `bssi', `bcci', `lbs', + `lbc'. NOTCOND is the opposite condition to COND. + (byte displacement) + `bCOND ...' + + (word displacement) + `bNOTCOND foo ; brw ... ; foo:' + + (long displacement) + `bNOTCOND foo ; jmp ... ; foo:' + +`jacbX' + X may be one of `b d f g h l w'. + (word displacement) + `OPCODE ...' + + (long displacement) + OPCODE ..., foo ; + brb bar ; + foo: jmp ... ; + bar: + +`jaobYYY' + YYY may be one of `lss leq'. + +`jsobZZZ' + ZZZ may be one of `geq gtr'. + (byte displacement) + `OPCODE ...' + + (word displacement) + OPCODE ..., foo ; + brb bar ; + foo: brw DESTINATION ; + bar: + + (long displacement) + OPCODE ..., foo ; + brb bar ; + foo: jmp DESTINATION ; + bar: + +`aobleq' +`aoblss' +`sobgeq' +`sobgtr' + + (byte displacement) + `OPCODE ...' + + (word displacement) + OPCODE ..., foo ; + brb bar ; + foo: brw DESTINATION ; + bar: + + (long displacement) + OPCODE ..., foo ; + brb bar ; + foo: jmp DESTINATION ; + bar: + + +File: as.info, Node: VAX-operands, Next: VAX-no, Prev: VAX-branch, Up: Vax-Dependent + +9.38.6 VAX Operands +------------------- + +The immediate character is `$' for Unix compatibility, not `#' as DEC +writes it. + + The indirect character is `*' for Unix compatibility, not `@' as DEC +writes it. + + The displacement sizing character is ``' (an accent grave) for Unix +compatibility, not `^' as DEC writes it. The letter preceding ``' may +have either case. `G' is not understood, but all other letters (`b i l +s w') are understood. + + Register names understood are `r0 r1 r2 ... r15 ap fp sp pc'. Upper +and lower case letters are equivalent. + + For instance + tstb *w`$4(r5) + + Any expression is permitted in an operand. Operands are comma +separated. + + +File: as.info, Node: VAX-no, Prev: VAX-operands, Up: Vax-Dependent + +9.38.7 Not Supported on VAX +--------------------------- + +Vax bit fields can not be assembled with `as'. Someone can add the +required code if they really need it. + + +File: as.info, Node: V850-Dependent, Next: Xtensa-Dependent, Prev: TIC54X-Dependent, Up: Machine Dependencies + +9.39 v850 Dependent Features +============================ + +* Menu: + +* V850 Options:: Options +* V850 Syntax:: Syntax +* V850 Floating Point:: Floating Point +* V850 Directives:: V850 Machine Directives +* V850 Opcodes:: Opcodes + + +File: as.info, Node: V850 Options, Next: V850 Syntax, Up: V850-Dependent + +9.39.1 Options +-------------- + +`as' supports the following additional command-line options for the +V850 processor family: + +`-wsigned_overflow' + Causes warnings to be produced when signed immediate values + overflow the space available for then within their opcodes. By + default this option is disabled as it is possible to receive + spurious warnings due to using exact bit patterns as immediate + constants. + +`-wunsigned_overflow' + Causes warnings to be produced when unsigned immediate values + overflow the space available for then within their opcodes. By + default this option is disabled as it is possible to receive + spurious warnings due to using exact bit patterns as immediate + constants. + +`-mv850' + Specifies that the assembled code should be marked as being + targeted at the V850 processor. This allows the linker to detect + attempts to link such code with code assembled for other + processors. + +`-mv850e' + Specifies that the assembled code should be marked as being + targeted at the V850E processor. This allows the linker to detect + attempts to link such code with code assembled for other + processors. + +`-mv850e1' + Specifies that the assembled code should be marked as being + targeted at the V850E1 processor. This allows the linker to + detect attempts to link such code with code assembled for other + processors. + +`-mv850any' + Specifies that the assembled code should be marked as being + targeted at the V850 processor but support instructions that are + specific to the extended variants of the process. This allows the + production of binaries that contain target specific code, but + which are also intended to be used in a generic fashion. For + example libgcc.a contains generic routines used by the code + produced by GCC for all versions of the v850 architecture, + together with support routines only used by the V850E architecture. + +`-mrelax' + Enables relaxation. This allows the .longcall and .longjump pseudo + ops to be used in the assembler source code. These ops label + sections of code which are either a long function call or a long + branch. The assembler will then flag these sections of code and + the linker will attempt to relax them. + + + +File: as.info, Node: V850 Syntax, Next: V850 Floating Point, Prev: V850 Options, Up: V850-Dependent + +9.39.2 Syntax +------------- + +* Menu: + +* V850-Chars:: Special Characters +* V850-Regs:: Register Names + + +File: as.info, Node: V850-Chars, Next: V850-Regs, Up: V850 Syntax + +9.39.2.1 Special Characters +........................... + +`#' is the line comment character. + + +File: as.info, Node: V850-Regs, Prev: V850-Chars, Up: V850 Syntax + +9.39.2.2 Register Names +....................... + +`as' supports the following names for registers: +`general register 0' + r0, zero + +`general register 1' + r1 + +`general register 2' + r2, hp + +`general register 3' + r3, sp + +`general register 4' + r4, gp + +`general register 5' + r5, tp + +`general register 6' + r6 + +`general register 7' + r7 + +`general register 8' + r8 + +`general register 9' + r9 + +`general register 10' + r10 + +`general register 11' + r11 + +`general register 12' + r12 + +`general register 13' + r13 + +`general register 14' + r14 + +`general register 15' + r15 + +`general register 16' + r16 + +`general register 17' + r17 + +`general register 18' + r18 + +`general register 19' + r19 + +`general register 20' + r20 + +`general register 21' + r21 + +`general register 22' + r22 + +`general register 23' + r23 + +`general register 24' + r24 + +`general register 25' + r25 + +`general register 26' + r26 + +`general register 27' + r27 + +`general register 28' + r28 + +`general register 29' + r29 + +`general register 30' + r30, ep + +`general register 31' + r31, lp + +`system register 0' + eipc + +`system register 1' + eipsw + +`system register 2' + fepc + +`system register 3' + fepsw + +`system register 4' + ecr + +`system register 5' + psw + +`system register 16' + ctpc + +`system register 17' + ctpsw + +`system register 18' + dbpc + +`system register 19' + dbpsw + +`system register 20' + ctbp + + +File: as.info, Node: V850 Floating Point, Next: V850 Directives, Prev: V850 Syntax, Up: V850-Dependent + +9.39.3 Floating Point +--------------------- + +The V850 family uses IEEE floating-point numbers. + + +File: as.info, Node: V850 Directives, Next: V850 Opcodes, Prev: V850 Floating Point, Up: V850-Dependent + +9.39.4 V850 Machine Directives +------------------------------ + +`.offset <EXPRESSION>' + Moves the offset into the current section to the specified amount. + +`.section "name", <type>' + This is an extension to the standard .section directive. It sets + the current section to be <type> and creates an alias for this + section called "name". + +`.v850' + Specifies that the assembled code should be marked as being + targeted at the V850 processor. This allows the linker to detect + attempts to link such code with code assembled for other + processors. + +`.v850e' + Specifies that the assembled code should be marked as being + targeted at the V850E processor. This allows the linker to detect + attempts to link such code with code assembled for other + processors. + +`.v850e1' + Specifies that the assembled code should be marked as being + targeted at the V850E1 processor. This allows the linker to + detect attempts to link such code with code assembled for other + processors. + + + +File: as.info, Node: V850 Opcodes, Prev: V850 Directives, Up: V850-Dependent + +9.39.5 Opcodes +-------------- + +`as' implements all the standard V850 opcodes. + + `as' also implements the following pseudo ops: + +`hi0()' + Computes the higher 16 bits of the given expression and stores it + into the immediate operand field of the given instruction. For + example: + + `mulhi hi0(here - there), r5, r6' + + computes the difference between the address of labels 'here' and + 'there', takes the upper 16 bits of this difference, shifts it + down 16 bits and then multiplies it by the lower 16 bits in + register 5, putting the result into register 6. + +`lo()' + Computes the lower 16 bits of the given expression and stores it + into the immediate operand field of the given instruction. For + example: + + `addi lo(here - there), r5, r6' + + computes the difference between the address of labels 'here' and + 'there', takes the lower 16 bits of this difference and adds it to + register 5, putting the result into register 6. + +`hi()' + Computes the higher 16 bits of the given expression and then adds + the value of the most significant bit of the lower 16 bits of the + expression and stores the result into the immediate operand field + of the given instruction. For example the following code can be + used to compute the address of the label 'here' and store it into + register 6: + + `movhi hi(here), r0, r6' `movea lo(here), r6, r6' + + The reason for this special behaviour is that movea performs a sign + extension on its immediate operand. So for example if the address + of 'here' was 0xFFFFFFFF then without the special behaviour of the + hi() pseudo-op the movhi instruction would put 0xFFFF0000 into r6, + then the movea instruction would takes its immediate operand, + 0xFFFF, sign extend it to 32 bits, 0xFFFFFFFF, and then add it + into r6 giving 0xFFFEFFFF which is wrong (the fifth nibble is E). + With the hi() pseudo op adding in the top bit of the lo() pseudo + op, the movhi instruction actually stores 0 into r6 (0xFFFF + 1 = + 0x0000), so that the movea instruction stores 0xFFFFFFFF into r6 - + the right value. + +`hilo()' + Computes the 32 bit value of the given expression and stores it + into the immediate operand field of the given instruction (which + must be a mov instruction). For example: + + `mov hilo(here), r6' + + computes the absolute address of label 'here' and puts the result + into register 6. + +`sdaoff()' + Computes the offset of the named variable from the start of the + Small Data Area (whoes address is held in register 4, the GP + register) and stores the result as a 16 bit signed value in the + immediate operand field of the given instruction. For example: + + `ld.w sdaoff(_a_variable)[gp],r6' + + loads the contents of the location pointed to by the label + '_a_variable' into register 6, provided that the label is located + somewhere within +/- 32K of the address held in the GP register. + [Note the linker assumes that the GP register contains a fixed + address set to the address of the label called '__gp'. This can + either be set up automatically by the linker, or specifically set + by using the `--defsym __gp=<value>' command line option]. + +`tdaoff()' + Computes the offset of the named variable from the start of the + Tiny Data Area (whoes address is held in register 30, the EP + register) and stores the result as a 4,5, 7 or 8 bit unsigned + value in the immediate operand field of the given instruction. + For example: + + `sld.w tdaoff(_a_variable)[ep],r6' + + loads the contents of the location pointed to by the label + '_a_variable' into register 6, provided that the label is located + somewhere within +256 bytes of the address held in the EP + register. [Note the linker assumes that the EP register contains + a fixed address set to the address of the label called '__ep'. + This can either be set up automatically by the linker, or + specifically set by using the `--defsym __ep=<value>' command line + option]. + +`zdaoff()' + Computes the offset of the named variable from address 0 and + stores the result as a 16 bit signed value in the immediate + operand field of the given instruction. For example: + + `movea zdaoff(_a_variable),zero,r6' + + puts the address of the label '_a_variable' into register 6, + assuming that the label is somewhere within the first 32K of + memory. (Strictly speaking it also possible to access the last + 32K of memory as well, as the offsets are signed). + +`ctoff()' + Computes the offset of the named variable from the start of the + Call Table Area (whoes address is helg in system register 20, the + CTBP register) and stores the result a 6 or 16 bit unsigned value + in the immediate field of then given instruction or piece of data. + For example: + + `callt ctoff(table_func1)' + + will put the call the function whoes address is held in the call + table at the location labeled 'table_func1'. + +`.longcall `name'' + Indicates that the following sequence of instructions is a long + call to function `name'. The linker will attempt to shorten this + call sequence if `name' is within a 22bit offset of the call. Only + valid if the `-mrelax' command line switch has been enabled. + +`.longjump `name'' + Indicates that the following sequence of instructions is a long + jump to label `name'. The linker will attempt to shorten this code + sequence if `name' is within a 22bit offset of the jump. Only + valid if the `-mrelax' command line switch has been enabled. + + + For information on the V850 instruction set, see `V850 Family +32-/16-Bit single-Chip Microcontroller Architecture Manual' from NEC. +Ltd. + + +File: as.info, Node: Xtensa-Dependent, Next: Z80-Dependent, Prev: V850-Dependent, Up: Machine Dependencies + +9.40 Xtensa Dependent Features +============================== + + This chapter covers features of the GNU assembler that are specific +to the Xtensa architecture. For details about the Xtensa instruction +set, please consult the `Xtensa Instruction Set Architecture (ISA) +Reference Manual'. + +* Menu: + +* Xtensa Options:: Command-line Options. +* Xtensa Syntax:: Assembler Syntax for Xtensa Processors. +* Xtensa Optimizations:: Assembler Optimizations. +* Xtensa Relaxation:: Other Automatic Transformations. +* Xtensa Directives:: Directives for Xtensa Processors. + + +File: as.info, Node: Xtensa Options, Next: Xtensa Syntax, Up: Xtensa-Dependent + +9.40.1 Command Line Options +--------------------------- + +The Xtensa version of the GNU assembler supports these special options: + +`--text-section-literals | --no-text-section-literals' + Control the treatment of literal pools. The default is + `--no-text-section-literals', which places literals in separate + sections in the output file. This allows the literal pool to be + placed in a data RAM/ROM. With `--text-section-literals', the + literals are interspersed in the text section in order to keep + them as close as possible to their references. This may be + necessary for large assembly files, where the literals would + otherwise be out of range of the `L32R' instructions in the text + section. These options only affect literals referenced via + PC-relative `L32R' instructions; literals for absolute mode `L32R' + instructions are handled separately. *Note literal: Literal + Directive. + +`--absolute-literals | --no-absolute-literals' + Indicate to the assembler whether `L32R' instructions use absolute + or PC-relative addressing. If the processor includes the absolute + addressing option, the default is to use absolute `L32R' + relocations. Otherwise, only the PC-relative `L32R' relocations + can be used. + +`--target-align | --no-target-align' + Enable or disable automatic alignment to reduce branch penalties + at some expense in code size. *Note Automatic Instruction + Alignment: Xtensa Automatic Alignment. This optimization is + enabled by default. Note that the assembler will always align + instructions like `LOOP' that have fixed alignment requirements. + +`--longcalls | --no-longcalls' + Enable or disable transformation of call instructions to allow + calls across a greater range of addresses. *Note Function Call + Relaxation: Xtensa Call Relaxation. This option should be used + when call targets can potentially be out of range. It may degrade + both code size and performance, but the linker can generally + optimize away the unnecessary overhead when a call ends up within + range. The default is `--no-longcalls'. + +`--transform | --no-transform' + Enable or disable all assembler transformations of Xtensa + instructions, including both relaxation and optimization. The + default is `--transform'; `--no-transform' should only be used in + the rare cases when the instructions must be exactly as specified + in the assembly source. Using `--no-transform' causes out of range + instruction operands to be errors. + +`--rename-section OLDNAME=NEWNAME' + Rename the OLDNAME section to NEWNAME. This option can be used + multiple times to rename multiple sections. + + +File: as.info, Node: Xtensa Syntax, Next: Xtensa Optimizations, Prev: Xtensa Options, Up: Xtensa-Dependent + +9.40.2 Assembler Syntax +----------------------- + +Block comments are delimited by `/*' and `*/'. End of line comments +may be introduced with either `#' or `//'. + + Instructions consist of a leading opcode or macro name followed by +whitespace and an optional comma-separated list of operands: + + OPCODE [OPERAND, ...] + + Instructions must be separated by a newline or semicolon. + + FLIX instructions, which bundle multiple opcodes together in a single +instruction, are specified by enclosing the bundled opcodes inside +braces: + + { + [FORMAT] + OPCODE0 [OPERANDS] + OPCODE1 [OPERANDS] + OPCODE2 [OPERANDS] + ... + } + + The opcodes in a FLIX instruction are listed in the same order as the +corresponding instruction slots in the TIE format declaration. +Directives and labels are not allowed inside the braces of a FLIX +instruction. A particular TIE format name can optionally be specified +immediately after the opening brace, but this is usually unnecessary. +The assembler will automatically search for a format that can encode the +specified opcodes, so the format name need only be specified in rare +cases where there is more than one applicable format and where it +matters which of those formats is used. A FLIX instruction can also be +specified on a single line by separating the opcodes with semicolons: + + { [FORMAT;] OPCODE0 [OPERANDS]; OPCODE1 [OPERANDS]; OPCODE2 [OPERANDS]; ... } + + If an opcode can only be encoded in a FLIX instruction but is not +specified as part of a FLIX bundle, the assembler will choose the +smallest format where the opcode can be encoded and will fill unused +instruction slots with no-ops. + +* Menu: + +* Xtensa Opcodes:: Opcode Naming Conventions. +* Xtensa Registers:: Register Naming. + + +File: as.info, Node: Xtensa Opcodes, Next: Xtensa Registers, Up: Xtensa Syntax + +9.40.2.1 Opcode Names +..................... + +See the `Xtensa Instruction Set Architecture (ISA) Reference Manual' +for a complete list of opcodes and descriptions of their semantics. + + If an opcode name is prefixed with an underscore character (`_'), +`as' will not transform that instruction in any way. The underscore +prefix disables both optimization (*note Xtensa Optimizations: Xtensa +Optimizations.) and relaxation (*note Xtensa Relaxation: Xtensa +Relaxation.) for that particular instruction. Only use the underscore +prefix when it is essential to select the exact opcode produced by the +assembler. Using this feature unnecessarily makes the code less +efficient by disabling assembler optimization and less flexible by +disabling relaxation. + + Note that this special handling of underscore prefixes only applies +to Xtensa opcodes, not to either built-in macros or user-defined macros. +When an underscore prefix is used with a macro (e.g., `_MOV'), it +refers to a different macro. The assembler generally provides built-in +macros both with and without the underscore prefix, where the underscore +versions behave as if the underscore carries through to the instructions +in the macros. For example, `_MOV' may expand to `_MOV.N'. + + The underscore prefix only applies to individual instructions, not to +series of instructions. For example, if a series of instructions have +underscore prefixes, the assembler will not transform the individual +instructions, but it may insert other instructions between them (e.g., +to align a `LOOP' instruction). To prevent the assembler from +modifying a series of instructions as a whole, use the `no-transform' +directive. *Note transform: Transform Directive. + + +File: as.info, Node: Xtensa Registers, Prev: Xtensa Opcodes, Up: Xtensa Syntax + +9.40.2.2 Register Names +....................... + +The assembly syntax for a register file entry is the "short" name for a +TIE register file followed by the index into that register file. For +example, the general-purpose `AR' register file has a short name of +`a', so these registers are named `a0'...`a15'. As a special feature, +`sp' is also supported as a synonym for `a1'. Additional registers may +be added by processor configuration options and by designer-defined TIE +extensions. An initial `$' character is optional in all register names. + + +File: as.info, Node: Xtensa Optimizations, Next: Xtensa Relaxation, Prev: Xtensa Syntax, Up: Xtensa-Dependent + +9.40.3 Xtensa Optimizations +--------------------------- + +The optimizations currently supported by `as' are generation of density +instructions where appropriate and automatic branch target alignment. + +* Menu: + +* Density Instructions:: Using Density Instructions. +* Xtensa Automatic Alignment:: Automatic Instruction Alignment. + + +File: as.info, Node: Density Instructions, Next: Xtensa Automatic Alignment, Up: Xtensa Optimizations + +9.40.3.1 Using Density Instructions +................................... + +The Xtensa instruction set has a code density option that provides +16-bit versions of some of the most commonly used opcodes. Use of these +opcodes can significantly reduce code size. When possible, the +assembler automatically translates instructions from the core Xtensa +instruction set into equivalent instructions from the Xtensa code +density option. This translation can be disabled by using underscore +prefixes (*note Opcode Names: Xtensa Opcodes.), by using the +`--no-transform' command-line option (*note Command Line Options: +Xtensa Options.), or by using the `no-transform' directive (*note +transform: Transform Directive.). + + It is a good idea _not_ to use the density instructions directly. +The assembler will automatically select dense instructions where +possible. If you later need to use an Xtensa processor without the code +density option, the same assembly code will then work without +modification. + + +File: as.info, Node: Xtensa Automatic Alignment, Prev: Density Instructions, Up: Xtensa Optimizations + +9.40.3.2 Automatic Instruction Alignment +........................................ + +The Xtensa assembler will automatically align certain instructions, both +to optimize performance and to satisfy architectural requirements. + + As an optimization to improve performance, the assembler attempts to +align branch targets so they do not cross instruction fetch boundaries. +(Xtensa processors can be configured with either 32-bit or 64-bit +instruction fetch widths.) An instruction immediately following a call +is treated as a branch target in this context, because it will be the +target of a return from the call. This alignment has the potential to +reduce branch penalties at some expense in code size. This +optimization is enabled by default. You can disable it with the +`--no-target-align' command-line option (*note Command Line Options: +Xtensa Options.). + + The target alignment optimization is done without adding instructions +that could increase the execution time of the program. If there are +density instructions in the code preceding a target, the assembler can +change the target alignment by widening some of those instructions to +the equivalent 24-bit instructions. Extra bytes of padding can be +inserted immediately following unconditional jump and return +instructions. This approach is usually successful in aligning many, +but not all, branch targets. + + The `LOOP' family of instructions must be aligned such that the +first instruction in the loop body does not cross an instruction fetch +boundary (e.g., with a 32-bit fetch width, a `LOOP' instruction must be +on either a 1 or 2 mod 4 byte boundary). The assembler knows about +this restriction and inserts the minimal number of 2 or 3 byte no-op +instructions to satisfy it. When no-op instructions are added, any +label immediately preceding the original loop will be moved in order to +refer to the loop instruction, not the newly generated no-op +instruction. To preserve binary compatibility across processors with +different fetch widths, the assembler conservatively assumes a 32-bit +fetch width when aligning `LOOP' instructions (except if the first +instruction in the loop is a 64-bit instruction). + + Previous versions of the assembler automatically aligned `ENTRY' +instructions to 4-byte boundaries, but that alignment is now the +programmer's responsibility. + + +File: as.info, Node: Xtensa Relaxation, Next: Xtensa Directives, Prev: Xtensa Optimizations, Up: Xtensa-Dependent + +9.40.4 Xtensa Relaxation +------------------------ + +When an instruction operand is outside the range allowed for that +particular instruction field, `as' can transform the code to use a +functionally-equivalent instruction or sequence of instructions. This +process is known as "relaxation". This is typically done for branch +instructions because the distance of the branch targets is not known +until assembly-time. The Xtensa assembler offers branch relaxation and +also extends this concept to function calls, `MOVI' instructions and +other instructions with immediate fields. + +* Menu: + +* Xtensa Branch Relaxation:: Relaxation of Branches. +* Xtensa Call Relaxation:: Relaxation of Function Calls. +* Xtensa Immediate Relaxation:: Relaxation of other Immediate Fields. + + +File: as.info, Node: Xtensa Branch Relaxation, Next: Xtensa Call Relaxation, Up: Xtensa Relaxation + +9.40.4.1 Conditional Branch Relaxation +...................................... + +When the target of a branch is too far away from the branch itself, +i.e., when the offset from the branch to the target is too large to fit +in the immediate field of the branch instruction, it may be necessary to +replace the branch with a branch around a jump. For example, + + beqz a2, L + + may result in: + + bnez.n a2, M + j L + M: + + (The `BNEZ.N' instruction would be used in this example only if the +density option is available. Otherwise, `BNEZ' would be used.) + + This relaxation works well because the unconditional jump instruction +has a much larger offset range than the various conditional branches. +However, an error will occur if a branch target is beyond the range of a +jump instruction. `as' cannot relax unconditional jumps. Similarly, +an error will occur if the original input contains an unconditional +jump to a target that is out of range. + + Branch relaxation is enabled by default. It can be disabled by using +underscore prefixes (*note Opcode Names: Xtensa Opcodes.), the +`--no-transform' command-line option (*note Command Line Options: +Xtensa Options.), or the `no-transform' directive (*note transform: +Transform Directive.). + + +File: as.info, Node: Xtensa Call Relaxation, Next: Xtensa Immediate Relaxation, Prev: Xtensa Branch Relaxation, Up: Xtensa Relaxation + +9.40.4.2 Function Call Relaxation +................................. + +Function calls may require relaxation because the Xtensa immediate call +instructions (`CALL0', `CALL4', `CALL8' and `CALL12') provide a +PC-relative offset of only 512 Kbytes in either direction. For larger +programs, it may be necessary to use indirect calls (`CALLX0', +`CALLX4', `CALLX8' and `CALLX12') where the target address is specified +in a register. The Xtensa assembler can automatically relax immediate +call instructions into indirect call instructions. This relaxation is +done by loading the address of the called function into the callee's +return address register and then using a `CALLX' instruction. So, for +example: + + call8 func + + might be relaxed to: + + .literal .L1, func + l32r a8, .L1 + callx8 a8 + + Because the addresses of targets of function calls are not generally +known until link-time, the assembler must assume the worst and relax all +the calls to functions in other source files, not just those that really +will be out of range. The linker can recognize calls that were +unnecessarily relaxed, and it will remove the overhead introduced by the +assembler for those cases where direct calls are sufficient. + + Call relaxation is disabled by default because it can have a negative +effect on both code size and performance, although the linker can +usually eliminate the unnecessary overhead. If a program is too large +and some of the calls are out of range, function call relaxation can be +enabled using the `--longcalls' command-line option or the `longcalls' +directive (*note longcalls: Longcalls Directive.). + + +File: as.info, Node: Xtensa Immediate Relaxation, Prev: Xtensa Call Relaxation, Up: Xtensa Relaxation + +9.40.4.3 Other Immediate Field Relaxation +......................................... + +The assembler normally performs the following other relaxations. They +can be disabled by using underscore prefixes (*note Opcode Names: +Xtensa Opcodes.), the `--no-transform' command-line option (*note +Command Line Options: Xtensa Options.), or the `no-transform' directive +(*note transform: Transform Directive.). + + The `MOVI' machine instruction can only materialize values in the +range from -2048 to 2047. Values outside this range are best +materialized with `L32R' instructions. Thus: + + movi a0, 100000 + + is assembled into the following machine code: + + .literal .L1, 100000 + l32r a0, .L1 + + The `L8UI' machine instruction can only be used with immediate +offsets in the range from 0 to 255. The `L16SI' and `L16UI' machine +instructions can only be used with offsets from 0 to 510. The `L32I' +machine instruction can only be used with offsets from 0 to 1020. A +load offset outside these ranges can be materialized with an `L32R' +instruction if the destination register of the load is different than +the source address register. For example: + + l32i a1, a0, 2040 + + is translated to: + + .literal .L1, 2040 + l32r a1, .L1 + add a1, a0, a1 + l32i a1, a1, 0 + +If the load destination and source address register are the same, an +out-of-range offset causes an error. + + The Xtensa `ADDI' instruction only allows immediate operands in the +range from -128 to 127. There are a number of alternate instruction +sequences for the `ADDI' operation. First, if the immediate is 0, the +`ADDI' will be turned into a `MOV.N' instruction (or the equivalent +`OR' instruction if the code density option is not available). If the +`ADDI' immediate is outside of the range -128 to 127, but inside the +range -32896 to 32639, an `ADDMI' instruction or `ADDMI'/`ADDI' +sequence will be used. Finally, if the immediate is outside of this +range and a free register is available, an `L32R'/`ADD' sequence will +be used with a literal allocated from the literal pool. + + For example: + + addi a5, a6, 0 + addi a5, a6, 512 + addi a5, a6, 513 + addi a5, a6, 50000 + + is assembled into the following: + + .literal .L1, 50000 + mov.n a5, a6 + addmi a5, a6, 0x200 + addmi a5, a6, 0x200 + addi a5, a5, 1 + l32r a5, .L1 + add a5, a6, a5 + + +File: as.info, Node: Xtensa Directives, Prev: Xtensa Relaxation, Up: Xtensa-Dependent + +9.40.5 Directives +----------------- + +The Xtensa assembler supports a region-based directive syntax: + + .begin DIRECTIVE [OPTIONS] + ... + .end DIRECTIVE + + All the Xtensa-specific directives that apply to a region of code use +this syntax. + + The directive applies to code between the `.begin' and the `.end'. +The state of the option after the `.end' reverts to what it was before +the `.begin'. A nested `.begin'/`.end' region can further change the +state of the directive without having to be aware of its outer state. +For example, consider: + + .begin no-transform + L: add a0, a1, a2 + .begin transform + M: add a0, a1, a2 + .end transform + N: add a0, a1, a2 + .end no-transform + + The `ADD' opcodes at `L' and `N' in the outer `no-transform' region +both result in `ADD' machine instructions, but the assembler selects an +`ADD.N' instruction for the `ADD' at `M' in the inner `transform' +region. + + The advantage of this style is that it works well inside macros +which can preserve the context of their callers. + + The following directives are available: + +* Menu: + +* Schedule Directive:: Enable instruction scheduling. +* Longcalls Directive:: Use Indirect Calls for Greater Range. +* Transform Directive:: Disable All Assembler Transformations. +* Literal Directive:: Intermix Literals with Instructions. +* Literal Position Directive:: Specify Inline Literal Pool Locations. +* Literal Prefix Directive:: Specify Literal Section Name Prefix. +* Absolute Literals Directive:: Control PC-Relative vs. Absolute Literals. + + +File: as.info, Node: Schedule Directive, Next: Longcalls Directive, Up: Xtensa Directives + +9.40.5.1 schedule +................. + +The `schedule' directive is recognized only for compatibility with +Tensilica's assembler. + + .begin [no-]schedule + .end [no-]schedule + + This directive is ignored and has no effect on `as'. + + +File: as.info, Node: Longcalls Directive, Next: Transform Directive, Prev: Schedule Directive, Up: Xtensa Directives + +9.40.5.2 longcalls +.................. + +The `longcalls' directive enables or disables function call relaxation. +*Note Function Call Relaxation: Xtensa Call Relaxation. + + .begin [no-]longcalls + .end [no-]longcalls + + Call relaxation is disabled by default unless the `--longcalls' +command-line option is specified. The `longcalls' directive overrides +the default determined by the command-line options. + + +File: as.info, Node: Transform Directive, Next: Literal Directive, Prev: Longcalls Directive, Up: Xtensa Directives + +9.40.5.3 transform +.................. + +This directive enables or disables all assembler transformation, +including relaxation (*note Xtensa Relaxation: Xtensa Relaxation.) and +optimization (*note Xtensa Optimizations: Xtensa Optimizations.). + + .begin [no-]transform + .end [no-]transform + + Transformations are enabled by default unless the `--no-transform' +option is used. The `transform' directive overrides the default +determined by the command-line options. An underscore opcode prefix, +disabling transformation of that opcode, always takes precedence over +both directives and command-line flags. + + +File: as.info, Node: Literal Directive, Next: Literal Position Directive, Prev: Transform Directive, Up: Xtensa Directives + +9.40.5.4 literal +................ + +The `.literal' directive is used to define literal pool data, i.e., +read-only 32-bit data accessed via `L32R' instructions. + + .literal LABEL, VALUE[, VALUE...] + + This directive is similar to the standard `.word' directive, except +that the actual location of the literal data is determined by the +assembler and linker, not by the position of the `.literal' directive. +Using this directive gives the assembler freedom to locate the literal +data in the most appropriate place and possibly to combine identical +literals. For example, the code: + + entry sp, 40 + .literal .L1, sym + l32r a4, .L1 + + can be used to load a pointer to the symbol `sym' into register +`a4'. The value of `sym' will not be placed between the `ENTRY' and +`L32R' instructions; instead, the assembler puts the data in a literal +pool. + + Literal pools are placed by default in separate literal sections; +however, when using the `--text-section-literals' option (*note Command +Line Options: Xtensa Options.), the literal pools for PC-relative mode +`L32R' instructions are placed in the current section.(1) These text +section literal pools are created automatically before `ENTRY' +instructions and manually after `.literal_position' directives (*note +literal_position: Literal Position Directive.). If there are no +preceding `ENTRY' instructions, explicit `.literal_position' directives +must be used to place the text section literal pools; otherwise, `as' +will report an error. + + When literals are placed in separate sections, the literal section +names are derived from the names of the sections where the literals are +defined. The base literal section names are `.literal' for PC-relative +mode `L32R' instructions and `.lit4' for absolute mode `L32R' +instructions (*note absolute-literals: Absolute Literals Directive.). +These base names are used for literals defined in the default `.text' +section. For literals defined in other sections or within the scope of +a `literal_prefix' directive (*note literal_prefix: Literal Prefix +Directive.), the following rules determine the literal section name: + + 1. If the current section is a member of a section group, the literal + section name includes the group name as a suffix to the base + `.literal' or `.lit4' name, with a period to separate the base + name and group name. The literal section is also made a member of + the group. + + 2. If the current section name (or `literal_prefix' value) begins with + "`.gnu.linkonce.KIND.'", the literal section name is formed by + replacing "`.KIND'" with the base `.literal' or `.lit4' name. For + example, for literals defined in a section named + `.gnu.linkonce.t.func', the literal section will be + `.gnu.linkonce.literal.func' or `.gnu.linkonce.lit4.func'. + + 3. If the current section name (or `literal_prefix' value) ends with + `.text', the literal section name is formed by replacing that + suffix with the base `.literal' or `.lit4' name. For example, for + literals defined in a section named `.iram0.text', the literal + section will be `.iram0.literal' or `.iram0.lit4'. + + 4. If none of the preceding conditions apply, the literal section + name is formed by adding the base `.literal' or `.lit4' name as a + suffix to the current section name (or `literal_prefix' value). + + ---------- Footnotes ---------- + + (1) Literals for the `.init' and `.fini' sections are always placed +in separate sections, even when `--text-section-literals' is enabled. + + +File: as.info, Node: Literal Position Directive, Next: Literal Prefix Directive, Prev: Literal Directive, Up: Xtensa Directives + +9.40.5.5 literal_position +......................... + +When using `--text-section-literals' to place literals inline in the +section being assembled, the `.literal_position' directive can be used +to mark a potential location for a literal pool. + + .literal_position + + The `.literal_position' directive is ignored when the +`--text-section-literals' option is not used or when `L32R' +instructions use the absolute addressing mode. + + The assembler will automatically place text section literal pools +before `ENTRY' instructions, so the `.literal_position' directive is +only needed to specify some other location for a literal pool. You may +need to add an explicit jump instruction to skip over an inline literal +pool. + + For example, an interrupt vector does not begin with an `ENTRY' +instruction so the assembler will be unable to automatically find a good +place to put a literal pool. Moreover, the code for the interrupt +vector must be at a specific starting address, so the literal pool +cannot come before the start of the code. The literal pool for the +vector must be explicitly positioned in the middle of the vector (before +any uses of the literals, due to the negative offsets used by +PC-relative `L32R' instructions). The `.literal_position' directive +can be used to do this. In the following code, the literal for `M' +will automatically be aligned correctly and is placed after the +unconditional jump. + + .global M + code_start: + j continue + .literal_position + .align 4 + continue: + movi a4, M + + +File: as.info, Node: Literal Prefix Directive, Next: Absolute Literals Directive, Prev: Literal Position Directive, Up: Xtensa Directives + +9.40.5.6 literal_prefix +....................... + +The `literal_prefix' directive allows you to override the default +literal section names, which are derived from the names of the sections +where the literals are defined. + + .begin literal_prefix [NAME] + .end literal_prefix + + For literals defined within the delimited region, the literal section +names are derived from the NAME argument instead of the name of the +current section. The rules used to derive the literal section names do +not change. *Note literal: Literal Directive. If the NAME argument is +omitted, the literal sections revert to the defaults. This directive +has no effect when using the `--text-section-literals' option (*note +Command Line Options: Xtensa Options.). + + +File: as.info, Node: Absolute Literals Directive, Prev: Literal Prefix Directive, Up: Xtensa Directives + +9.40.5.7 absolute-literals +.......................... + +The `absolute-literals' and `no-absolute-literals' directives control +the absolute vs. PC-relative mode for `L32R' instructions. These are +relevant only for Xtensa configurations that include the absolute +addressing option for `L32R' instructions. + + .begin [no-]absolute-literals + .end [no-]absolute-literals + + These directives do not change the `L32R' mode--they only cause the +assembler to emit the appropriate kind of relocation for `L32R' +instructions and to place the literal values in the appropriate section. +To change the `L32R' mode, the program must write the `LITBASE' special +register. It is the programmer's responsibility to keep track of the +mode and indicate to the assembler which mode is used in each region of +code. + + If the Xtensa configuration includes the absolute `L32R' addressing +option, the default is to assume absolute `L32R' addressing unless the +`--no-absolute-literals' command-line option is specified. Otherwise, +the default is to assume PC-relative `L32R' addressing. The +`absolute-literals' directive can then be used to override the default +determined by the command-line options. + + +File: as.info, Node: Reporting Bugs, Next: Acknowledgements, Prev: Machine Dependencies, Up: Top + +10 Reporting Bugs +***************** + +Your bug reports play an essential role in making `as' reliable. + + Reporting a bug may help you by bringing a solution to your problem, +or it may not. But in any case the principal function of a bug report +is to help the entire community by making the next version of `as' work +better. Bug reports are your contribution to the maintenance of `as'. + + In order for a bug report to serve its purpose, you must include the +information that enables us to fix the bug. + +* Menu: + +* Bug Criteria:: Have you found a bug? +* Bug Reporting:: How to report bugs + + +File: as.info, Node: Bug Criteria, Next: Bug Reporting, Up: Reporting Bugs + +10.1 Have You Found a Bug? +========================== + +If you are not sure whether you have found a bug, here are some +guidelines: + + * If the assembler gets a fatal signal, for any input whatever, that + is a `as' bug. Reliable assemblers never crash. + + * If `as' produces an error message for valid input, that is a bug. + + * If `as' does not produce an error message for invalid input, that + is a bug. However, you should note that your idea of "invalid + input" might be our idea of "an extension" or "support for + traditional practice". + + * If you are an experienced user of assemblers, your suggestions for + improvement of `as' are welcome in any case. + + +File: as.info, Node: Bug Reporting, Prev: Bug Criteria, Up: Reporting Bugs + +10.2 How to Report Bugs +======================= + +A number of companies and individuals offer support for GNU products. +If you obtained `as' from a support organization, we recommend you +contact that organization first. + + You can find contact information for many support companies and +individuals in the file `etc/SERVICE' in the GNU Emacs distribution. + + In any event, we also recommend that you send bug reports for `as' +to `http://www.sourceware.org/bugzilla/'. + + The fundamental principle of reporting bugs usefully is this: +*report all the facts*. If you are not sure whether to state a fact or +leave it out, state it! + + Often people omit facts because they think they know what causes the +problem and assume that some details do not matter. Thus, you might +assume that the name of a symbol you use in an example does not matter. +Well, probably it does not, but one cannot be sure. Perhaps the bug +is a stray memory reference which happens to fetch from the location +where that name is stored in memory; perhaps, if the name were +different, the contents of that location would fool the assembler into +doing the right thing despite the bug. Play it safe and give a +specific, complete example. That is the easiest thing for you to do, +and the most helpful. + + Keep in mind that the purpose of a bug report is to enable us to fix +the bug if it is new to us. Therefore, always write your bug reports +on the assumption that the bug has not been reported previously. + + Sometimes people give a few sketchy facts and ask, "Does this ring a +bell?" This cannot help us fix a bug, so it is basically useless. We +respond by asking for enough details to enable us to investigate. You +might as well expedite matters by sending them to begin with. + + To enable us to fix the bug, you should include all these things: + + * The version of `as'. `as' announces it if you start it with the + `--version' argument. + + Without this, we will not know whether there is any point in + looking for the bug in the current version of `as'. + + * Any patches you may have applied to the `as' source. + + * The type of machine you are using, and the operating system name + and version number. + + * What compiler (and its version) was used to compile `as'--e.g. + "`gcc-2.7'". + + * The command arguments you gave the assembler to assemble your + example and observe the bug. To guarantee you will not omit + something important, list them all. A copy of the Makefile (or + the output from make) is sufficient. + + If we were to try to guess the arguments, we would probably guess + wrong and then we might not encounter the bug. + + * A complete input file that will reproduce the bug. If the bug is + observed when the assembler is invoked via a compiler, send the + assembler source, not the high level language source. Most + compilers will produce the assembler source when run with the `-S' + option. If you are using `gcc', use the options `-v + --save-temps'; this will save the assembler source in a file with + an extension of `.s', and also show you exactly how `as' is being + run. + + * A description of what behavior you observe that you believe is + incorrect. For example, "It gets a fatal signal." + + Of course, if the bug is that `as' gets a fatal signal, then we + will certainly notice it. But if the bug is incorrect output, we + might not notice unless it is glaringly wrong. You might as well + not give us a chance to make a mistake. + + Even if the problem you experience is a fatal signal, you should + still say so explicitly. Suppose something strange is going on, + such as, your copy of `as' is out of sync, or you have encountered + a bug in the C library on your system. (This has happened!) Your + copy might crash and ours would not. If you told us to expect a + crash, then when ours fails to crash, we would know that the bug + was not happening for us. If you had not told us to expect a + crash, then we would not be able to draw any conclusion from our + observations. + + * If you wish to suggest changes to the `as' source, send us context + diffs, as generated by `diff' with the `-u', `-c', or `-p' option. + Always send diffs from the old file to the new file. If you even + discuss something in the `as' source, refer to it by context, not + by line number. + + The line numbers in our development sources will not match those + in your sources. Your line numbers would convey no useful + information to us. + + Here are some things that are not necessary: + + * A description of the envelope of the bug. + + Often people who encounter a bug spend a lot of time investigating + which changes to the input file will make the bug go away and which + changes will not affect it. + + This is often time consuming and not very useful, because the way + we will find the bug is by running a single example under the + debugger with breakpoints, not by pure deduction from a series of + examples. We recommend that you save your time for something else. + + Of course, if you can find a simpler example to report _instead_ + of the original one, that is a convenience for us. Errors in the + output will be easier to spot, running under the debugger will take + less time, and so on. + + However, simplification is not vital; if you do not want to do + this, report the bug anyway and send us the entire test case you + used. + + * A patch for the bug. + + A patch for the bug does help us if it is a good one. But do not + omit the necessary information, such as the test case, on the + assumption that a patch is all we need. We might see problems + with your patch and decide to fix the problem another way, or we + might not understand it at all. + + Sometimes with a program as complicated as `as' it is very hard to + construct an example that will make the program follow a certain + path through the code. If you do not send us the example, we will + not be able to construct one, so we will not be able to verify + that the bug is fixed. + + And if we cannot understand what bug you are trying to fix, or why + your patch should be an improvement, we will not install it. A + test case will help us to understand. + + * A guess about what the bug is or what it depends on. + + Such guesses are usually wrong. Even we cannot guess right about + such things without first using the debugger to find the facts. + + +File: as.info, Node: Acknowledgements, Next: GNU Free Documentation License, Prev: Reporting Bugs, Up: Top + +11 Acknowledgements +******************* + +If you have contributed to GAS and your name isn't listed here, it is +not meant as a slight. We just don't know about it. Send mail to the +maintainer, and we'll correct the situation. Currently the maintainer +is Ken Raeburn (email address `raeburn@cygnus.com'). + + Dean Elsner wrote the original GNU assembler for the VAX.(1) + + Jay Fenlason maintained GAS for a while, adding support for +GDB-specific debug information and the 68k series machines, most of the +preprocessing pass, and extensive changes in `messages.c', +`input-file.c', `write.c'. + + K. Richard Pixley maintained GAS for a while, adding various +enhancements and many bug fixes, including merging support for several +processors, breaking GAS up to handle multiple object file format back +ends (including heavy rewrite, testing, an integration of the coff and +b.out back ends), adding configuration including heavy testing and +verification of cross assemblers and file splits and renaming, +converted GAS to strictly ANSI C including full prototypes, added +support for m680[34]0 and cpu32, did considerable work on i960 +including a COFF port (including considerable amounts of reverse +engineering), a SPARC opcode file rewrite, DECstation, rs6000, and +hp300hpux host ports, updated "know" assertions and made them work, +much other reorganization, cleanup, and lint. + + Ken Raeburn wrote the high-level BFD interface code to replace most +of the code in format-specific I/O modules. + + The original VMS support was contributed by David L. Kashtan. Eric +Youngdale has done much work with it since. + + The Intel 80386 machine description was written by Eliot Dresselhaus. + + Minh Tran-Le at IntelliCorp contributed some AIX 386 support. + + The Motorola 88k machine description was contributed by Devon Bowen +of Buffalo University and Torbjorn Granlund of the Swedish Institute of +Computer Science. + + Keith Knowles at the Open Software Foundation wrote the original +MIPS back end (`tc-mips.c', `tc-mips.h'), and contributed Rose format +support (which hasn't been merged in yet). Ralph Campbell worked with +the MIPS code to support a.out format. + + Support for the Zilog Z8k and Renesas H8/300 processors (tc-z8k, +tc-h8300), and IEEE 695 object file format (obj-ieee), was written by +Steve Chamberlain of Cygnus Support. Steve also modified the COFF back +end to use BFD for some low-level operations, for use with the H8/300 +and AMD 29k targets. + + John Gilmore built the AMD 29000 support, added `.include' support, +and simplified the configuration of which versions accept which +directives. He updated the 68k machine description so that Motorola's +opcodes always produced fixed-size instructions (e.g., `jsr'), while +synthetic instructions remained shrinkable (`jbsr'). John fixed many +bugs, including true tested cross-compilation support, and one bug in +relaxation that took a week and required the proverbial one-bit fix. + + Ian Lance Taylor of Cygnus Support merged the Motorola and MIT +syntax for the 68k, completed support for some COFF targets (68k, i386 +SVR3, and SCO Unix), added support for MIPS ECOFF and ELF targets, +wrote the initial RS/6000 and PowerPC assembler, and made a few other +minor patches. + + Steve Chamberlain made GAS able to generate listings. + + Hewlett-Packard contributed support for the HP9000/300. + + Jeff Law wrote GAS and BFD support for the native HPPA object format +(SOM) along with a fairly extensive HPPA testsuite (for both SOM and +ELF object formats). This work was supported by both the Center for +Software Science at the University of Utah and Cygnus Support. + + Support for ELF format files has been worked on by Mark Eichin of +Cygnus Support (original, incomplete implementation for SPARC), Pete +Hoogenboom and Jeff Law at the University of Utah (HPPA mainly), +Michael Meissner of the Open Software Foundation (i386 mainly), and Ken +Raeburn of Cygnus Support (sparc, and some initial 64-bit support). + + Linas Vepstas added GAS support for the ESA/390 "IBM 370" +architecture. + + Richard Henderson rewrote the Alpha assembler. Klaus Kaempf wrote +GAS and BFD support for openVMS/Alpha. + + Timothy Wall, Michael Hayes, and Greg Smart contributed to the +various tic* flavors. + + David Heine, Sterling Augustine, Bob Wilson and John Ruttenberg from +Tensilica, Inc. added support for Xtensa processors. + + Several engineers at Cygnus Support have also provided many small +bug fixes and configuration enhancements. + + Jon Beniston added support for the Lattice Mico32 architecture. + + Many others have contributed large or small bugfixes and +enhancements. If you have contributed significant work and are not +mentioned on this list, and want to be, let us know. Some of the +history has been lost; we are not intentionally leaving anyone out. + + ---------- Footnotes ---------- + + (1) Any more details? + + +File: as.info, Node: GNU Free Documentation License, Next: AS Index, Prev: Acknowledgements, Up: Top + +Appendix A GNU Free Documentation License +***************************************** + + Version 1.3, 3 November 2008 + + Copyright (C) 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc. + `http://fsf.org/' + + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + 0. PREAMBLE + + The purpose of this License is to make a manual, textbook, or other + functional and useful document "free" in the sense of freedom: to + assure everyone the effective freedom to copy and redistribute it, + with or without modifying it, either commercially or + noncommercially. Secondarily, this License preserves for the + author and publisher a way to get credit for their work, while not + being considered responsible for modifications made by others. + + This License is a kind of "copyleft", which means that derivative + works of the document must themselves be free in the same sense. + It complements the GNU General Public License, which is a copyleft + license designed for free software. + + We have designed this License in order to use it for manuals for + free software, because free software needs free documentation: a + free program should come with manuals providing the same freedoms + that the software does. But this License is not limited to + software manuals; it can be used for any textual work, regardless + of subject matter or whether it is published as a printed book. + We recommend this License principally for works whose purpose is + instruction or reference. + + 1. 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A copy of the license is included in the section entitled ``GNU + Free Documentation License''. + + If you have Invariant Sections, Front-Cover Texts and Back-Cover +Texts, replace the "with...Texts." line with this: + + with the Invariant Sections being LIST THEIR TITLES, with + the Front-Cover Texts being LIST, and with the Back-Cover Texts + being LIST. + + If you have Invariant Sections without Cover Texts, or some other +combination of the three, merge those two alternatives to suit the +situation. + + If your document contains nontrivial examples of program code, we +recommend releasing these examples in parallel under your choice of +free software license, such as the GNU General Public License, to +permit their use in free software. + + +File: as.info, Node: AS Index, Prev: GNU Free Documentation License, Up: Top + +AS Index +******** + + +* Menu: + +* #: Comments. (line 39) +* #APP: Preprocessing. (line 27) +* #NO_APP: Preprocessing. (line 27) +* $ in symbol names <1>: D30V-Chars. (line 63) +* $ in symbol names <2>: SH64-Chars. (line 10) +* $ in symbol names <3>: D10V-Chars. (line 46) +* $ in symbol names: SH-Chars. (line 10) +* $a: ARM Mapping Symbols. (line 9) +* $acos math builtin, TIC54X: TIC54X-Builtins. (line 10) +* $asin math builtin, TIC54X: TIC54X-Builtins. (line 13) +* $atan math builtin, TIC54X: TIC54X-Builtins. (line 16) +* $atan2 math builtin, TIC54X: TIC54X-Builtins. (line 19) +* $ceil math builtin, TIC54X: TIC54X-Builtins. (line 22) +* $cos math builtin, TIC54X: TIC54X-Builtins. (line 28) +* $cosh math builtin, TIC54X: TIC54X-Builtins. (line 25) +* $cvf math builtin, TIC54X: TIC54X-Builtins. (line 31) +* $cvi math builtin, TIC54X: TIC54X-Builtins. (line 34) +* $d: ARM Mapping Symbols. (line 15) +* $exp math builtin, TIC54X: TIC54X-Builtins. (line 37) +* $fabs math builtin, TIC54X: TIC54X-Builtins. (line 40) +* $firstch subsym builtin, TIC54X: TIC54X-Macros. (line 26) +* $floor math builtin, TIC54X: TIC54X-Builtins. (line 43) +* $fmod math builtin, TIC54X: TIC54X-Builtins. (line 47) +* $int math builtin, TIC54X: TIC54X-Builtins. (line 50) +* $iscons subsym builtin, TIC54X: TIC54X-Macros. (line 43) +* $isdefed subsym builtin, TIC54X: TIC54X-Macros. (line 34) +* $ismember subsym builtin, TIC54X: TIC54X-Macros. (line 38) +* $isname subsym builtin, TIC54X: TIC54X-Macros. (line 47) +* $isreg subsym builtin, TIC54X: TIC54X-Macros. (line 50) +* $lastch subsym builtin, TIC54X: TIC54X-Macros. (line 30) +* $ldexp math builtin, TIC54X: TIC54X-Builtins. (line 53) +* $log math builtin, TIC54X: TIC54X-Builtins. (line 59) +* $log10 math builtin, TIC54X: TIC54X-Builtins. (line 56) +* $max math builtin, TIC54X: TIC54X-Builtins. (line 62) +* $min math builtin, TIC54X: TIC54X-Builtins. (line 65) +* $pow math builtin, TIC54X: TIC54X-Builtins. (line 68) +* $round math builtin, TIC54X: TIC54X-Builtins. (line 71) +* $sgn math builtin, TIC54X: TIC54X-Builtins. (line 74) +* $sin math builtin, TIC54X: TIC54X-Builtins. (line 77) +* $sinh math builtin, TIC54X: TIC54X-Builtins. (line 80) +* $sqrt math builtin, TIC54X: TIC54X-Builtins. (line 83) +* $structacc subsym builtin, TIC54X: TIC54X-Macros. (line 57) +* $structsz subsym builtin, TIC54X: TIC54X-Macros. (line 54) +* $symcmp subsym builtin, TIC54X: TIC54X-Macros. (line 23) +* $symlen subsym builtin, TIC54X: TIC54X-Macros. (line 20) +* $t: ARM Mapping Symbols. (line 12) +* $tan math builtin, TIC54X: TIC54X-Builtins. (line 86) +* $tanh math builtin, TIC54X: TIC54X-Builtins. (line 89) +* $trunc math builtin, TIC54X: TIC54X-Builtins. (line 92) +* -+ option, VAX/VMS: VAX-Opts. (line 71) +* --: Command Line. (line 10) +* --32 option, i386: i386-Options. (line 8) +* --32 option, x86-64: i386-Options. (line 8) +* --64 option, i386: i386-Options. (line 8) +* --64 option, x86-64: i386-Options. (line 8) +* --absolute-literals: Xtensa Options. (line 23) +* --allow-reg-prefix: SH Options. (line 9) +* --alternate: alternate. (line 6) +* --base-size-default-16: M68K-Opts. (line 71) +* --base-size-default-32: M68K-Opts. (line 71) +* --big: SH Options. (line 9) +* --bitwise-or option, M680x0: M68K-Opts. (line 64) +* --disp-size-default-16: M68K-Opts. (line 80) +* --disp-size-default-32: M68K-Opts. (line 80) +* --divide option, i386: i386-Options. (line 24) +* --dsp: SH Options. (line 9) +* --emulation=crisaout command line option, CRIS: CRIS-Opts. (line 9) +* --emulation=criself command line option, CRIS: CRIS-Opts. (line 9) +* --enforce-aligned-data: Sparc-Aligned-Data. (line 11) +* --fatal-warnings: W. (line 16) +* --fix-v4bx command line option, ARM: ARM Options. (line 143) +* --fixed-special-register-names command line option, MMIX: MMIX-Opts. + (line 8) +* --force-long-branches: M68HC11-Opts. (line 69) +* --generate-example: M68HC11-Opts. (line 86) +* --globalize-symbols command line option, MMIX: MMIX-Opts. (line 12) +* --gnu-syntax command line option, MMIX: MMIX-Opts. (line 16) +* --hash-size=NUMBER: Overview. (line 326) +* --linker-allocated-gregs command line option, MMIX: MMIX-Opts. + (line 67) +* --listing-cont-lines: listing. (line 34) +* --listing-lhs-width: listing. (line 16) +* --listing-lhs-width2: listing. (line 21) +* --listing-rhs-width: listing. (line 28) +* --little: SH Options. (line 9) +* --longcalls: Xtensa Options. (line 37) +* --march=ARCHITECTURE command line option, CRIS: CRIS-Opts. (line 33) +* --MD: MD. (line 6) +* --mul-bug-abort command line option, CRIS: CRIS-Opts. (line 61) +* --no-absolute-literals: Xtensa Options. (line 23) +* --no-expand command line option, MMIX: MMIX-Opts. (line 31) +* --no-longcalls: Xtensa Options. (line 37) +* --no-merge-gregs command line option, MMIX: MMIX-Opts. (line 36) +* --no-mul-bug-abort command line option, CRIS: CRIS-Opts. (line 61) +* --no-predefined-syms command line option, MMIX: MMIX-Opts. (line 22) +* --no-pushj-stubs command line option, MMIX: MMIX-Opts. (line 54) +* --no-stubs command line option, MMIX: MMIX-Opts. (line 54) +* --no-target-align: Xtensa Options. (line 30) +* --no-text-section-literals: Xtensa Options. (line 9) +* --no-transform: Xtensa Options. (line 46) +* --no-underscore command line option, CRIS: CRIS-Opts. (line 15) +* --no-warn: W. (line 11) +* --pcrel: M68K-Opts. (line 92) +* --pic command line option, CRIS: CRIS-Opts. (line 27) +* --print-insn-syntax: M68HC11-Opts. (line 75) +* --print-opcodes: M68HC11-Opts. (line 79) +* --register-prefix-optional option, M680x0: M68K-Opts. (line 51) +* --relax: SH Options. (line 9) +* --relax command line option, MMIX: MMIX-Opts. (line 19) +* --rename-section: Xtensa Options. (line 54) +* --renesas: SH Options. (line 9) +* --short-branches: M68HC11-Opts. (line 54) +* --small: SH Options. (line 9) +* --statistics: statistics. (line 6) +* --strict-direct-mode: M68HC11-Opts. (line 44) +* --target-align: Xtensa Options. (line 30) +* --text-section-literals: Xtensa Options. (line 9) +* --traditional-format: traditional-format. (line 6) +* --transform: Xtensa Options. (line 46) +* --underscore command line option, CRIS: CRIS-Opts. (line 15) +* --warn: W. (line 19) +* -1 option, VAX/VMS: VAX-Opts. (line 77) +* -32addr command line option, Alpha: Alpha Options. (line 58) +* -a: a. (line 6) +* -A options, i960: Options-i960. (line 6) +* -ac: a. (line 6) +* -ad: a. (line 6) +* -ag: a. (line 6) +* -ah: a. (line 6) +* -al: a. (line 6) +* -an: a. (line 6) +* -as: a. (line 6) +* -Asparclet: Sparc-Opts. (line 25) +* -Asparclite: Sparc-Opts. (line 25) +* -Av6: Sparc-Opts. (line 25) +* -Av8: Sparc-Opts. (line 25) +* -Av9: Sparc-Opts. (line 25) +* -Av9a: Sparc-Opts. (line 25) +* -b option, i960: Options-i960. (line 22) +* -big option, M32R: M32R-Opts. (line 35) +* -D: D. (line 6) +* -D, ignored on VAX: VAX-Opts. (line 11) +* -d, VAX option: VAX-Opts. (line 16) +* -eabi= command line option, ARM: ARM Options. (line 126) +* -EB command line option, ARC: ARC Options. (line 31) +* -EB command line option, ARM: ARM Options. (line 131) +* -EB option (MIPS): MIPS Opts. (line 13) +* -EB option, M32R: M32R-Opts. (line 39) +* -EL command line option, ARC: ARC Options. (line 35) +* -EL command line option, ARM: ARM Options. (line 135) +* -EL option (MIPS): MIPS Opts. (line 13) +* -EL option, M32R: M32R-Opts. (line 32) +* -f: f. (line 6) +* -F command line option, Alpha: Alpha Options. (line 58) +* -G command line option, Alpha: Alpha Options. (line 54) +* -g command line option, Alpha: Alpha Options. (line 48) +* -G option (MIPS): MIPS Opts. (line 8) +* -H option, VAX/VMS: VAX-Opts. (line 81) +* -h option, VAX/VMS: VAX-Opts. (line 45) +* -I PATH: I. (line 6) +* -ignore-parallel-conflicts option, M32RX: M32R-Opts. (line 87) +* -Ip option, M32RX: M32R-Opts. (line 97) +* -J, ignored on VAX: VAX-Opts. (line 27) +* -K: K. (line 6) +* -k command line option, ARM: ARM Options. (line 139) +* -KPIC option, M32R: M32R-Opts. (line 42) +* -KPIC option, MIPS: MIPS Opts. (line 21) +* -L: L. (line 6) +* -l option, M680x0: M68K-Opts. (line 39) +* -little option, M32R: M32R-Opts. (line 27) +* -M: M. (line 6) +* -m11/03: PDP-11-Options. (line 140) +* -m11/04: PDP-11-Options. (line 143) +* -m11/05: PDP-11-Options. (line 146) +* -m11/10: PDP-11-Options. (line 146) +* -m11/15: PDP-11-Options. (line 149) +* -m11/20: PDP-11-Options. (line 149) +* -m11/21: PDP-11-Options. (line 152) +* -m11/23: PDP-11-Options. (line 155) +* -m11/24: PDP-11-Options. (line 155) +* -m11/34: PDP-11-Options. (line 158) +* -m11/34a: PDP-11-Options. (line 161) +* -m11/35: PDP-11-Options. (line 164) +* -m11/40: PDP-11-Options. (line 164) +* -m11/44: PDP-11-Options. (line 167) +* -m11/45: PDP-11-Options. (line 170) +* -m11/50: PDP-11-Options. (line 170) +* -m11/53: PDP-11-Options. (line 173) +* -m11/55: PDP-11-Options. (line 170) +* -m11/60: PDP-11-Options. (line 176) +* -m11/70: PDP-11-Options. (line 170) +* -m11/73: PDP-11-Options. (line 173) +* -m11/83: PDP-11-Options. (line 173) +* -m11/84: PDP-11-Options. (line 173) +* -m11/93: PDP-11-Options. (line 173) +* -m11/94: PDP-11-Options. (line 173) +* -m16c option, M16C: M32C-Opts. (line 12) +* -m31 option, s390: s390 Options. (line 8) +* -m32c option, M32C: M32C-Opts. (line 9) +* -m32r option, M32R: M32R-Opts. (line 21) +* -m32rx option, M32R2: M32R-Opts. (line 17) +* -m32rx option, M32RX: M32R-Opts. (line 9) +* -m64 option, s390: s390 Options. (line 8) +* -m68000 and related options: M68K-Opts. (line 104) +* -m68hc11: M68HC11-Opts. (line 9) +* -m68hc12: M68HC11-Opts. (line 14) +* -m68hcs12: M68HC11-Opts. (line 21) +* -m[no-]68851 command line option, M680x0: M68K-Opts. (line 21) +* -m[no-]68881 command line option, M680x0: M68K-Opts. (line 21) +* -m[no-]div command line option, M680x0: M68K-Opts. (line 21) +* -m[no-]emac command line option, M680x0: M68K-Opts. (line 21) +* -m[no-]float command line option, M680x0: M68K-Opts. (line 21) +* -m[no-]mac command line option, M680x0: M68K-Opts. (line 21) +* -m[no-]usp command line option, M680x0: M68K-Opts. (line 21) +* -mall: PDP-11-Options. (line 26) +* -mall-enabled command line option, LM32: LM32 Options. (line 30) +* -mall-extensions: PDP-11-Options. (line 26) +* -mall-opcodes command line option, AVR: AVR Options. (line 62) +* -mapcs command line option, ARM: ARM Options. (line 99) +* -mapcs-float command line option, ARM: ARM Options. (line 112) +* -mapcs-reentrant command line option, ARM: ARM Options. (line 117) +* -marc[5|6|7|8] command line option, ARC: ARC Options. (line 6) +* -march= command line option, ARM: ARM Options. (line 40) +* -march= command line option, M680x0: M68K-Opts. (line 8) +* -march= option, i386: i386-Options. (line 31) +* -march= option, s390: s390 Options. (line 25) +* -march= option, x86-64: i386-Options. (line 31) +* -matpcs command line option, ARM: ARM Options. (line 104) +* -mbarrel-shift-enabled command line option, LM32: LM32 Options. + (line 12) +* -mbreak-enabled command line option, LM32: LM32 Options. (line 27) +* -mcis: PDP-11-Options. (line 32) +* -mconstant-gp command line option, IA-64: IA-64 Options. (line 6) +* -mCPU command line option, Alpha: Alpha Options. (line 6) +* -mcpu option, cpu: TIC54X-Opts. (line 15) +* -mcpu= command line option, ARM: ARM Options. (line 6) +* -mcpu= command line option, Blackfin: Blackfin Options. (line 6) +* -mcpu= command line option, M680x0: M68K-Opts. (line 14) +* -mcsm: PDP-11-Options. (line 43) +* -mdcache-enabled command line option, LM32: LM32 Options. (line 24) +* -mdebug command line option, Alpha: Alpha Options. (line 25) +* -mdivide-enabled command line option, LM32: LM32 Options. (line 9) +* -me option, stderr redirect: TIC54X-Opts. (line 20) +* -meis: PDP-11-Options. (line 46) +* -merrors-to-file option, stderr redirect: TIC54X-Opts. (line 20) +* -mesa option, s390: s390 Options. (line 17) +* -mf option, far-mode: TIC54X-Opts. (line 8) +* -mf11: PDP-11-Options. (line 122) +* -mfar-mode option, far-mode: TIC54X-Opts. (line 8) +* -mfis: PDP-11-Options. (line 51) +* -mfloat-abi= command line option, ARM: ARM Options. (line 121) +* -mfp-11: PDP-11-Options. (line 56) +* -mfpp: PDP-11-Options. (line 56) +* -mfpu: PDP-11-Options. (line 56) +* -mfpu= command line option, ARM: ARM Options. (line 55) +* -micache-enabled command line option, LM32: LM32 Options. (line 21) +* -mimplicit-it command line option, ARM: ARM Options. (line 83) +* -mip2022 option, IP2K: IP2K-Opts. (line 14) +* -mip2022ext option, IP2022: IP2K-Opts. (line 9) +* -mj11: PDP-11-Options. (line 126) +* -mka11: PDP-11-Options. (line 92) +* -mkb11: PDP-11-Options. (line 95) +* -mkd11a: PDP-11-Options. (line 98) +* -mkd11b: PDP-11-Options. (line 101) +* -mkd11d: PDP-11-Options. (line 104) +* -mkd11e: PDP-11-Options. (line 107) +* -mkd11f: PDP-11-Options. (line 110) +* -mkd11h: PDP-11-Options. (line 110) +* -mkd11k: PDP-11-Options. (line 114) +* -mkd11q: PDP-11-Options. (line 110) +* -mkd11z: PDP-11-Options. (line 118) +* -mkev11: PDP-11-Options. (line 51) +* -mlimited-eis: PDP-11-Options. (line 64) +* -mlong: M68HC11-Opts. (line 32) +* -mlong-double: M68HC11-Opts. (line 40) +* -mmcu= command line option, AVR: AVR Options. (line 6) +* -mmfpt: PDP-11-Options. (line 70) +* -mmicrocode: PDP-11-Options. (line 83) +* -mmnemonic= option, i386: i386-Options. (line 80) +* -mmnemonic= option, x86-64: i386-Options. (line 80) +* -mmultiply-enabled command line option, LM32: LM32 Options. (line 6) +* -mmutiproc: PDP-11-Options. (line 73) +* -mmxps: PDP-11-Options. (line 77) +* -mnaked-reg option, i386: i386-Options. (line 94) +* -mnaked-reg option, x86-64: i386-Options. (line 94) +* -mno-cis: PDP-11-Options. (line 32) +* -mno-csm: PDP-11-Options. (line 43) +* -mno-eis: PDP-11-Options. (line 46) +* -mno-extensions: PDP-11-Options. (line 29) +* -mno-fis: PDP-11-Options. (line 51) +* -mno-fp-11: PDP-11-Options. (line 56) +* -mno-fpp: PDP-11-Options. (line 56) +* -mno-fpu: PDP-11-Options. (line 56) +* -mno-kev11: PDP-11-Options. (line 51) +* -mno-limited-eis: PDP-11-Options. (line 64) +* -mno-mfpt: PDP-11-Options. (line 70) +* -mno-microcode: PDP-11-Options. (line 83) +* -mno-mutiproc: PDP-11-Options. (line 73) +* -mno-mxps: PDP-11-Options. (line 77) +* -mno-pic: PDP-11-Options. (line 11) +* -mno-regnames option, s390: s390 Options. (line 35) +* -mno-skip-bug command line option, AVR: AVR Options. (line 65) +* -mno-spl: PDP-11-Options. (line 80) +* -mno-sym32: MIPS Opts. (line 189) +* -mno-wrap command line option, AVR: AVR Options. (line 68) +* -mpic: PDP-11-Options. (line 11) +* -mregnames option, s390: s390 Options. (line 32) +* -mrelax command line option, V850: V850 Options. (line 51) +* -mshort: M68HC11-Opts. (line 27) +* -mshort-double: M68HC11-Opts. (line 36) +* -msign-extend-enabled command line option, LM32: LM32 Options. + (line 15) +* -mspl: PDP-11-Options. (line 80) +* -msse-check= option, i386: i386-Options. (line 68) +* -msse-check= option, x86-64: i386-Options. (line 68) +* -msse2avx option, i386: i386-Options. (line 64) +* -msse2avx option, x86-64: i386-Options. (line 64) +* -msym32: MIPS Opts. (line 189) +* -msyntax= option, i386: i386-Options. (line 87) +* -msyntax= option, x86-64: i386-Options. (line 87) +* -mt11: PDP-11-Options. (line 130) +* -mthumb command line option, ARM: ARM Options. (line 74) +* -mthumb-interwork command line option, ARM: ARM Options. (line 79) +* -mtune= option, i386: i386-Options. (line 56) +* -mtune= option, x86-64: i386-Options. (line 56) +* -muser-enabled command line option, LM32: LM32 Options. (line 18) +* -mv850 command line option, V850: V850 Options. (line 23) +* -mv850any command line option, V850: V850 Options. (line 41) +* -mv850e command line option, V850: V850 Options. (line 29) +* -mv850e1 command line option, V850: V850 Options. (line 35) +* -mvxworks-pic option, MIPS: MIPS Opts. (line 26) +* -mwarn-areg-zero option, s390: s390 Options. (line 38) +* -mwarn-deprecated command line option, ARM: ARM Options. (line 147) +* -mzarch option, s390: s390 Options. (line 17) +* -N command line option, CRIS: CRIS-Opts. (line 57) +* -nIp option, M32RX: M32R-Opts. (line 101) +* -no-bitinst, M32R2: M32R-Opts. (line 54) +* -no-ignore-parallel-conflicts option, M32RX: M32R-Opts. (line 93) +* -no-mdebug command line option, Alpha: Alpha Options. (line 25) +* -no-parallel option, M32RX: M32R-Opts. (line 51) +* -no-relax option, i960: Options-i960. (line 66) +* -no-warn-explicit-parallel-conflicts option, M32RX: M32R-Opts. + (line 79) +* -no-warn-unmatched-high option, M32R: M32R-Opts. (line 111) +* -nocpp ignored (MIPS): MIPS Opts. (line 192) +* -noreplace command line option, Alpha: Alpha Options. (line 40) +* -o: o. (line 6) +* -O option, M32RX: M32R-Opts. (line 59) +* -parallel option, M32RX: M32R-Opts. (line 46) +* -R: R. (line 6) +* -r800 command line option, Z80: Z80 Options. (line 41) +* -relax command line option, Alpha: Alpha Options. (line 32) +* -replace command line option, Alpha: Alpha Options. (line 40) +* -S, ignored on VAX: VAX-Opts. (line 11) +* -t, ignored on VAX: VAX-Opts. (line 36) +* -T, ignored on VAX: VAX-Opts. (line 11) +* -v: v. (line 6) +* -V, redundant on VAX: VAX-Opts. (line 22) +* -version: v. (line 6) +* -W: W. (line 11) +* -warn-explicit-parallel-conflicts option, M32RX: M32R-Opts. (line 65) +* -warn-unmatched-high option, M32R: M32R-Opts. (line 105) +* -Wnp option, M32RX: M32R-Opts. (line 83) +* -Wnuh option, M32RX: M32R-Opts. (line 117) +* -Wp option, M32RX: M32R-Opts. (line 75) +* -wsigned_overflow command line option, V850: V850 Options. (line 9) +* -Wuh option, M32RX: M32R-Opts. (line 114) +* -wunsigned_overflow command line option, V850: V850 Options. + (line 16) +* -x command line option, MMIX: MMIX-Opts. (line 44) +* -z80 command line option, Z80: Z80 Options. (line 8) +* -z8001 command line option, Z8000: Z8000 Options. (line 6) +* -z8002 command line option, Z8000: Z8000 Options. (line 9) +* . (symbol): Dot. (line 6) +* .2byte directive, ARM: ARM Directives. (line 6) +* .4byte directive, ARM: ARM Directives. (line 6) +* .8byte directive, ARM: ARM Directives. (line 6) +* .align directive, ARM: ARM Directives. (line 11) +* .arch directive, ARM: ARM Directives. (line 18) +* .arm directive, ARM: ARM Directives. (line 22) +* .big directive, M32RX: M32R-Directives. (line 88) +* .bss directive, ARM: ARM Directives. (line 30) +* .cantunwind directive, ARM: ARM Directives. (line 33) +* .code directive, ARM: ARM Directives. (line 37) +* .cpu directive, ARM: ARM Directives. (line 41) +* .dn and .qn directives, ARM: ARM Directives. (line 45) +* .eabi_attribute directive, ARM: ARM Directives. (line 69) +* .even directive, ARM: ARM Directives. (line 93) +* .extend directive, ARM: ARM Directives. (line 96) +* .fnend directive, ARM: ARM Directives. (line 102) +* .fnstart directive, ARM: ARM Directives. (line 111) +* .force_thumb directive, ARM: ARM Directives. (line 114) +* .fpu directive, ARM: ARM Directives. (line 118) +* .global: MIPS insn. (line 12) +* .handlerdata directive, ARM: ARM Directives. (line 122) +* .insn: MIPS insn. (line 6) +* .insn directive, s390: s390 Directives. (line 11) +* .inst directive, ARM: ARM Directives. (line 131) +* .ldouble directive, ARM: ARM Directives. (line 96) +* .little directive, M32RX: M32R-Directives. (line 82) +* .long directive, s390: s390 Directives. (line 16) +* .ltorg directive, ARM: ARM Directives. (line 143) +* .ltorg directive, s390: s390 Directives. (line 88) +* .m32r directive, M32R: M32R-Directives. (line 66) +* .m32r2 directive, M32R2: M32R-Directives. (line 77) +* .m32rx directive, M32RX: M32R-Directives. (line 72) +* .movsp directive, ARM: ARM Directives. (line 157) +* .o: Object. (line 6) +* .object_arch directive, ARM: ARM Directives. (line 162) +* .packed directive, ARM: ARM Directives. (line 168) +* .pad directive, ARM: ARM Directives. (line 25) +* .param on HPPA: HPPA Directives. (line 19) +* .personality directive, ARM: ARM Directives. (line 178) +* .personalityindex directive, ARM: ARM Directives. (line 181) +* .pool directive, ARM: ARM Directives. (line 185) +* .quad directive, s390: s390 Directives. (line 16) +* .req directive, ARM: ARM Directives. (line 188) +* .save directive, ARM: ARM Directives. (line 193) +* .secrel32 directive, ARM: ARM Directives. (line 231) +* .set arch=CPU: MIPS ISA. (line 18) +* .set autoextend: MIPS autoextend. (line 6) +* .set doublefloat: MIPS floating-point. (line 12) +* .set dsp: MIPS ASE instruction generation overrides. + (line 21) +* .set dspr2: MIPS ASE instruction generation overrides. + (line 26) +* .set hardfloat: MIPS floating-point. (line 6) +* .set mdmx: MIPS ASE instruction generation overrides. + (line 16) +* .set mips3d: MIPS ASE instruction generation overrides. + (line 6) +* .set mipsN: MIPS ISA. (line 6) +* .set mt: MIPS ASE instruction generation overrides. + (line 32) +* .set noautoextend: MIPS autoextend. (line 6) +* .set nodsp: MIPS ASE instruction generation overrides. + (line 21) +* .set nodspr2: MIPS ASE instruction generation overrides. + (line 26) +* .set nomdmx: MIPS ASE instruction generation overrides. + (line 16) +* .set nomips3d: MIPS ASE instruction generation overrides. + (line 6) +* .set nomt: MIPS ASE instruction generation overrides. + (line 32) +* .set nosmartmips: MIPS ASE instruction generation overrides. + (line 11) +* .set nosym32: MIPS symbol sizes. (line 6) +* .set pop: MIPS option stack. (line 6) +* .set push: MIPS option stack. (line 6) +* .set singlefloat: MIPS floating-point. (line 12) +* .set smartmips: MIPS ASE instruction generation overrides. + (line 11) +* .set softfloat: MIPS floating-point. (line 6) +* .set sym32: MIPS symbol sizes. (line 6) +* .setfp directive, ARM: ARM Directives. (line 217) +* .short directive, s390: s390 Directives. (line 16) +* .syntax directive, ARM: ARM Directives. (line 236) +* .thumb directive, ARM: ARM Directives. (line 240) +* .thumb_func directive, ARM: ARM Directives. (line 243) +* .thumb_set directive, ARM: ARM Directives. (line 254) +* .unreq directive, ARM: ARM Directives. (line 261) +* .unwind_raw directive, ARM: ARM Directives. (line 272) +* .v850 directive, V850: V850 Directives. (line 14) +* .v850e directive, V850: V850 Directives. (line 20) +* .v850e1 directive, V850: V850 Directives. (line 26) +* .vsave directive, ARM: ARM Directives. (line 279) +* .z8001: Z8000 Directives. (line 11) +* .z8002: Z8000 Directives. (line 15) +* 16-bit code, i386: i386-16bit. (line 6) +* 2byte directive, ARC: ARC Directives. (line 9) +* 3byte directive, ARC: ARC Directives. (line 12) +* 3DNow!, i386: i386-SIMD. (line 6) +* 3DNow!, x86-64: i386-SIMD. (line 6) +* 430 support: MSP430-Dependent. (line 6) +* 4byte directive, ARC: ARC Directives. (line 15) +* : (label): Statements. (line 30) +* @word modifier, D10V: D10V-Word. (line 6) +* \" (doublequote character): Strings. (line 43) +* \\ (\ character): Strings. (line 40) +* \b (backspace character): Strings. (line 15) +* \DDD (octal character code): Strings. (line 30) +* \f (formfeed character): Strings. (line 18) +* \n (newline character): Strings. (line 21) +* \r (carriage return character): Strings. (line 24) +* \t (tab): Strings. (line 27) +* \XD... (hex character code): Strings. (line 36) +* _ opcode prefix: Xtensa Opcodes. (line 9) +* a.out: Object. (line 6) +* a.out symbol attributes: a.out Symbols. (line 6) +* A_DIR environment variable, TIC54X: TIC54X-Env. (line 6) +* ABI options, SH64: SH64 Options. (line 29) +* abort directive: Abort. (line 6) +* ABORT directive: ABORT (COFF). (line 6) +* absolute section: Ld Sections. (line 29) +* absolute-literals directive: Absolute Literals Directive. + (line 6) +* ADDI instructions, relaxation: Xtensa Immediate Relaxation. + (line 43) +* addition, permitted arguments: Infix Ops. (line 44) +* addresses: Expressions. (line 6) +* addresses, format of: Secs Background. (line 68) +* addressing modes, D10V: D10V-Addressing. (line 6) +* addressing modes, D30V: D30V-Addressing. (line 6) +* addressing modes, H8/300: H8/300-Addressing. (line 6) +* addressing modes, M680x0: M68K-Syntax. (line 21) +* addressing modes, M68HC11: M68HC11-Syntax. (line 17) +* addressing modes, SH: SH-Addressing. (line 6) +* addressing modes, SH64: SH64-Addressing. (line 6) +* addressing modes, Z8000: Z8000-Addressing. (line 6) +* ADR reg,<label> pseudo op, ARM: ARM Opcodes. (line 25) +* ADRL reg,<label> pseudo op, ARM: ARM Opcodes. (line 35) +* advancing location counter: Org. (line 6) +* align directive: Align. (line 6) +* align directive, SPARC: Sparc-Directives. (line 9) +* align directive, TIC54X: TIC54X-Directives. (line 6) +* alignment of branch targets: Xtensa Automatic Alignment. + (line 6) +* alignment of LOOP instructions: Xtensa Automatic Alignment. + (line 6) +* Alpha floating point (IEEE): Alpha Floating Point. + (line 6) +* Alpha line comment character: Alpha-Chars. (line 6) +* Alpha line separator: Alpha-Chars. (line 8) +* Alpha notes: Alpha Notes. (line 6) +* Alpha options: Alpha Options. (line 6) +* Alpha registers: Alpha-Regs. (line 6) +* Alpha relocations: Alpha-Relocs. (line 6) +* Alpha support: Alpha-Dependent. (line 6) +* Alpha Syntax: Alpha Options. (line 62) +* Alpha-only directives: Alpha Directives. (line 10) +* altered difference tables: Word. (line 12) +* alternate syntax for the 680x0: M68K-Moto-Syntax. (line 6) +* ARC floating point (IEEE): ARC Floating Point. (line 6) +* ARC machine directives: ARC Directives. (line 6) +* ARC opcodes: ARC Opcodes. (line 6) +* ARC options (none): ARC Options. (line 6) +* ARC register names: ARC-Regs. (line 6) +* ARC special characters: ARC-Chars. (line 6) +* ARC support: ARC-Dependent. (line 6) +* arc5 arc5, ARC: ARC Options. (line 10) +* arc6 arc6, ARC: ARC Options. (line 13) +* arc7 arc7, ARC: ARC Options. (line 21) +* arc8 arc8, ARC: ARC Options. (line 24) +* arch directive, i386: i386-Arch. (line 6) +* arch directive, M680x0: M68K-Directives. (line 22) +* arch directive, x86-64: i386-Arch. (line 6) +* architecture options, i960: Options-i960. (line 6) +* architecture options, IP2022: IP2K-Opts. (line 9) +* architecture options, IP2K: IP2K-Opts. (line 14) +* architecture options, M16C: M32C-Opts. (line 12) +* architecture options, M32C: M32C-Opts. (line 9) +* architecture options, M32R: M32R-Opts. (line 21) +* architecture options, M32R2: M32R-Opts. (line 17) +* architecture options, M32RX: M32R-Opts. (line 9) +* architecture options, M680x0: M68K-Opts. (line 104) +* Architecture variant option, CRIS: CRIS-Opts. (line 33) +* architectures, PowerPC: PowerPC-Opts. (line 6) +* architectures, SCORE: SCORE-Opts. (line 6) +* architectures, SPARC: Sparc-Opts. (line 6) +* arguments for addition: Infix Ops. (line 44) +* arguments for subtraction: Infix Ops. (line 49) +* arguments in expressions: Arguments. (line 6) +* arithmetic functions: Operators. (line 6) +* arithmetic operands: Arguments. (line 6) +* ARM data relocations: ARM-Relocations. (line 6) +* ARM floating point (IEEE): ARM Floating Point. (line 6) +* ARM identifiers: ARM-Chars. (line 15) +* ARM immediate character: ARM-Chars. (line 13) +* ARM line comment character: ARM-Chars. (line 6) +* ARM line separator: ARM-Chars. (line 10) +* ARM machine directives: ARM Directives. (line 6) +* ARM opcodes: ARM Opcodes. (line 6) +* ARM options (none): ARM Options. (line 6) +* ARM register names: ARM-Regs. (line 6) +* ARM support: ARM-Dependent. (line 6) +* ascii directive: Ascii. (line 6) +* asciz directive: Asciz. (line 6) +* asg directive, TIC54X: TIC54X-Directives. (line 20) +* assembler bugs, reporting: Bug Reporting. (line 6) +* assembler crash: Bug Criteria. (line 9) +* assembler directive .arch, CRIS: CRIS-Pseudos. (line 45) +* assembler directive .dword, CRIS: CRIS-Pseudos. (line 12) +* assembler directive .far, M68HC11: M68HC11-Directives. (line 20) +* assembler directive .interrupt, M68HC11: M68HC11-Directives. + (line 26) +* assembler directive .mode, M68HC11: M68HC11-Directives. (line 16) +* assembler directive .relax, M68HC11: M68HC11-Directives. (line 10) +* assembler directive .syntax, CRIS: CRIS-Pseudos. (line 17) +* assembler directive .xrefb, M68HC11: M68HC11-Directives. (line 31) +* assembler directive BSPEC, MMIX: MMIX-Pseudos. (line 131) +* assembler directive BYTE, MMIX: MMIX-Pseudos. (line 97) +* assembler directive ESPEC, MMIX: MMIX-Pseudos. (line 131) +* assembler directive GREG, MMIX: MMIX-Pseudos. (line 50) +* assembler directive IS, MMIX: MMIX-Pseudos. (line 42) +* assembler directive LOC, MMIX: MMIX-Pseudos. (line 7) +* assembler directive LOCAL, MMIX: MMIX-Pseudos. (line 28) +* assembler directive OCTA, MMIX: MMIX-Pseudos. (line 108) +* assembler directive PREFIX, MMIX: MMIX-Pseudos. (line 120) +* assembler directive TETRA, MMIX: MMIX-Pseudos. (line 108) +* assembler directive WYDE, MMIX: MMIX-Pseudos. (line 108) +* assembler directives, CRIS: CRIS-Pseudos. (line 6) +* assembler directives, M68HC11: M68HC11-Directives. (line 6) +* assembler directives, M68HC12: M68HC11-Directives. (line 6) +* assembler directives, MMIX: MMIX-Pseudos. (line 6) +* assembler internal logic error: As Sections. (line 13) +* assembler version: v. (line 6) +* assembler, and linker: Secs Background. (line 10) +* assembly listings, enabling: a. (line 6) +* assigning values to symbols <1>: Setting Symbols. (line 6) +* assigning values to symbols: Equ. (line 6) +* atmp directive, i860: Directives-i860. (line 16) +* att_syntax pseudo op, i386: i386-Syntax. (line 6) +* att_syntax pseudo op, x86-64: i386-Syntax. (line 6) +* attributes, symbol: Symbol Attributes. (line 6) +* auxiliary attributes, COFF symbols: COFF Symbols. (line 19) +* auxiliary symbol information, COFF: Dim. (line 6) +* Av7: Sparc-Opts. (line 25) +* AVR line comment character: AVR-Chars. (line 6) +* AVR line separator: AVR-Chars. (line 10) +* AVR modifiers: AVR-Modifiers. (line 6) +* AVR opcode summary: AVR Opcodes. (line 6) +* AVR options (none): AVR Options. (line 6) +* AVR register names: AVR-Regs. (line 6) +* AVR support: AVR-Dependent. (line 6) +* backslash (\\): Strings. (line 40) +* backspace (\b): Strings. (line 15) +* balign directive: Balign. (line 6) +* balignl directive: Balign. (line 27) +* balignw directive: Balign. (line 27) +* bes directive, TIC54X: TIC54X-Directives. (line 197) +* big endian output, MIPS: Overview. (line 641) +* big endian output, PJ: Overview. (line 548) +* big-endian output, MIPS: MIPS Opts. (line 13) +* bignums: Bignums. (line 6) +* binary constants, TIC54X: TIC54X-Constants. (line 8) +* binary files, including: Incbin. (line 6) +* binary integers: Integers. (line 6) +* bit names, IA-64: IA-64-Bits. (line 6) +* bitfields, not supported on VAX: VAX-no. (line 6) +* Blackfin directives: Blackfin Directives. (line 6) +* Blackfin options (none): Blackfin Options. (line 6) +* Blackfin support: Blackfin-Dependent. (line 6) +* Blackfin syntax: Blackfin Syntax. (line 6) +* block: Z8000 Directives. (line 55) +* branch improvement, M680x0: M68K-Branch. (line 6) +* branch improvement, M68HC11: M68HC11-Branch. (line 6) +* branch improvement, VAX: VAX-branch. (line 6) +* branch instructions, relaxation: Xtensa Branch Relaxation. + (line 6) +* branch recording, i960: Options-i960. (line 22) +* branch statistics table, i960: Options-i960. (line 40) +* branch target alignment: Xtensa Automatic Alignment. + (line 6) +* break directive, TIC54X: TIC54X-Directives. (line 143) +* BSD syntax: PDP-11-Syntax. (line 6) +* bss directive, i960: Directives-i960. (line 6) +* bss directive, TIC54X: TIC54X-Directives. (line 29) +* bss section <1>: bss. (line 6) +* bss section: Ld Sections. (line 20) +* bug criteria: Bug Criteria. (line 6) +* bug reports: Bug Reporting. (line 6) +* bugs in assembler: Reporting Bugs. (line 6) +* Built-in symbols, CRIS: CRIS-Symbols. (line 6) +* builtin math functions, TIC54X: TIC54X-Builtins. (line 6) +* builtin subsym functions, TIC54X: TIC54X-Macros. (line 16) +* bus lock prefixes, i386: i386-Prefixes. (line 36) +* bval: Z8000 Directives. (line 30) +* byte directive: Byte. (line 6) +* byte directive, TIC54X: TIC54X-Directives. (line 36) +* C54XDSP_DIR environment variable, TIC54X: TIC54X-Env. (line 6) +* c_mode directive, TIC54X: TIC54X-Directives. (line 51) +* call instructions, i386: i386-Mnemonics. (line 55) +* call instructions, relaxation: Xtensa Call Relaxation. + (line 6) +* call instructions, x86-64: i386-Mnemonics. (line 55) +* callj, i960 pseudo-opcode: callj-i960. (line 6) +* carriage return (\r): Strings. (line 24) +* case sensitivity, Z80: Z80-Case. (line 6) +* cfi_endproc directive: CFI directives. (line 26) +* cfi_sections directive: CFI directives. (line 13) +* cfi_startproc directive: CFI directives. (line 6) +* char directive, TIC54X: TIC54X-Directives. (line 36) +* character constant, Z80: Z80-Chars. (line 13) +* character constants: Characters. (line 6) +* character escape codes: Strings. (line 15) +* character escapes, Z80: Z80-Chars. (line 11) +* character, single: Chars. (line 6) +* characters used in symbols: Symbol Intro. (line 6) +* clink directive, TIC54X: TIC54X-Directives. (line 45) +* code16 directive, i386: i386-16bit. (line 6) +* code16gcc directive, i386: i386-16bit. (line 6) +* code32 directive, i386: i386-16bit. (line 6) +* code64 directive, i386: i386-16bit. (line 6) +* code64 directive, x86-64: i386-16bit. (line 6) +* COFF auxiliary symbol information: Dim. (line 6) +* COFF structure debugging: Tag. (line 6) +* COFF symbol attributes: COFF Symbols. (line 6) +* COFF symbol descriptor: Desc. (line 6) +* COFF symbol storage class: Scl. (line 6) +* COFF symbol type: Type. (line 11) +* COFF symbols, debugging: Def. (line 6) +* COFF value attribute: Val. (line 6) +* COMDAT: Linkonce. (line 6) +* comm directive: Comm. (line 6) +* command line conventions: Command Line. (line 6) +* command line options, V850: V850 Options. (line 9) +* command-line options ignored, VAX: VAX-Opts. (line 6) +* comments: Comments. (line 6) +* comments, M680x0: M68K-Chars. (line 6) +* comments, removed by preprocessor: Preprocessing. (line 11) +* common directive, SPARC: Sparc-Directives. (line 12) +* common sections: Linkonce. (line 6) +* common variable storage: bss. (line 6) +* compare and jump expansions, i960: Compare-and-branch-i960. + (line 13) +* compare/branch instructions, i960: Compare-and-branch-i960. + (line 6) +* comparison expressions: Infix Ops. (line 55) +* conditional assembly: If. (line 6) +* constant, single character: Chars. (line 6) +* constants: Constants. (line 6) +* constants, bignum: Bignums. (line 6) +* constants, character: Characters. (line 6) +* constants, converted by preprocessor: Preprocessing. (line 14) +* constants, floating point: Flonums. (line 6) +* constants, integer: Integers. (line 6) +* constants, number: Numbers. (line 6) +* constants, Sparc: Sparc-Constants. (line 6) +* constants, string: Strings. (line 6) +* constants, TIC54X: TIC54X-Constants. (line 6) +* conversion instructions, i386: i386-Mnemonics. (line 36) +* conversion instructions, x86-64: i386-Mnemonics. (line 36) +* coprocessor wait, i386: i386-Prefixes. (line 40) +* copy directive, TIC54X: TIC54X-Directives. (line 54) +* cpu directive, M680x0: M68K-Directives. (line 30) +* CR16 Operand Qualifiers: CR16 Operand Qualifiers. + (line 6) +* CR16 support: CR16-Dependent. (line 6) +* crash of assembler: Bug Criteria. (line 9) +* CRIS --emulation=crisaout command line option: CRIS-Opts. (line 9) +* CRIS --emulation=criself command line option: CRIS-Opts. (line 9) +* CRIS --march=ARCHITECTURE command line option: CRIS-Opts. (line 33) +* CRIS --mul-bug-abort command line option: CRIS-Opts. (line 61) +* CRIS --no-mul-bug-abort command line option: CRIS-Opts. (line 61) +* CRIS --no-underscore command line option: CRIS-Opts. (line 15) +* CRIS --pic command line option: CRIS-Opts. (line 27) +* CRIS --underscore command line option: CRIS-Opts. (line 15) +* CRIS -N command line option: CRIS-Opts. (line 57) +* CRIS architecture variant option: CRIS-Opts. (line 33) +* CRIS assembler directive .arch: CRIS-Pseudos. (line 45) +* CRIS assembler directive .dword: CRIS-Pseudos. (line 12) +* CRIS assembler directive .syntax: CRIS-Pseudos. (line 17) +* CRIS assembler directives: CRIS-Pseudos. (line 6) +* CRIS built-in symbols: CRIS-Symbols. (line 6) +* CRIS instruction expansion: CRIS-Expand. (line 6) +* CRIS line comment characters: CRIS-Chars. (line 6) +* CRIS options: CRIS-Opts. (line 6) +* CRIS position-independent code: CRIS-Opts. (line 27) +* CRIS pseudo-op .arch: CRIS-Pseudos. (line 45) +* CRIS pseudo-op .dword: CRIS-Pseudos. (line 12) +* CRIS pseudo-op .syntax: CRIS-Pseudos. (line 17) +* CRIS pseudo-ops: CRIS-Pseudos. (line 6) +* CRIS register names: CRIS-Regs. (line 6) +* CRIS support: CRIS-Dependent. (line 6) +* CRIS symbols in position-independent code: CRIS-Pic. (line 6) +* ctbp register, V850: V850-Regs. (line 131) +* ctoff pseudo-op, V850: V850 Opcodes. (line 111) +* ctpc register, V850: V850-Regs. (line 119) +* ctpsw register, V850: V850-Regs. (line 122) +* current address: Dot. (line 6) +* current address, advancing: Org. (line 6) +* D10V @word modifier: D10V-Word. (line 6) +* D10V addressing modes: D10V-Addressing. (line 6) +* D10V floating point: D10V-Float. (line 6) +* D10V line comment character: D10V-Chars. (line 6) +* D10V opcode summary: D10V-Opcodes. (line 6) +* D10V optimization: Overview. (line 420) +* D10V options: D10V-Opts. (line 6) +* D10V registers: D10V-Regs. (line 6) +* D10V size modifiers: D10V-Size. (line 6) +* D10V sub-instruction ordering: D10V-Chars. (line 6) +* D10V sub-instructions: D10V-Subs. (line 6) +* D10V support: D10V-Dependent. (line 6) +* D10V syntax: D10V-Syntax. (line 6) +* D30V addressing modes: D30V-Addressing. (line 6) +* D30V floating point: D30V-Float. (line 6) +* D30V Guarded Execution: D30V-Guarded. (line 6) +* D30V line comment character: D30V-Chars. (line 6) +* D30V nops: Overview. (line 428) +* D30V nops after 32-bit multiply: Overview. (line 431) +* D30V opcode summary: D30V-Opcodes. (line 6) +* D30V optimization: Overview. (line 425) +* D30V options: D30V-Opts. (line 6) +* D30V registers: D30V-Regs. (line 6) +* D30V size modifiers: D30V-Size. (line 6) +* D30V sub-instruction ordering: D30V-Chars. (line 6) +* D30V sub-instructions: D30V-Subs. (line 6) +* D30V support: D30V-Dependent. (line 6) +* D30V syntax: D30V-Syntax. (line 6) +* data alignment on SPARC: Sparc-Aligned-Data. (line 6) +* data and text sections, joining: R. (line 6) +* data directive: Data. (line 6) +* data directive, TIC54X: TIC54X-Directives. (line 61) +* data relocations, ARM: ARM-Relocations. (line 6) +* data section: Ld Sections. (line 9) +* data1 directive, M680x0: M68K-Directives. (line 9) +* data2 directive, M680x0: M68K-Directives. (line 12) +* datalabel, SH64: SH64-Addressing. (line 16) +* dbpc register, V850: V850-Regs. (line 125) +* dbpsw register, V850: V850-Regs. (line 128) +* debuggers, and symbol order: Symbols. (line 10) +* debugging COFF symbols: Def. (line 6) +* DEC syntax: PDP-11-Syntax. (line 6) +* decimal integers: Integers. (line 12) +* def directive: Def. (line 6) +* def directive, TIC54X: TIC54X-Directives. (line 103) +* density instructions: Density Instructions. + (line 6) +* dependency tracking: MD. (line 6) +* deprecated directives: Deprecated. (line 6) +* desc directive: Desc. (line 6) +* descriptor, of a.out symbol: Symbol Desc. (line 6) +* dfloat directive, VAX: VAX-directives. (line 10) +* difference tables altered: Word. (line 12) +* difference tables, warning: K. (line 6) +* differences, mmixal: MMIX-mmixal. (line 6) +* dim directive: Dim. (line 6) +* directives and instructions: Statements. (line 19) +* directives for PowerPC: PowerPC-Pseudo. (line 6) +* directives for SCORE: SCORE-Pseudo. (line 6) +* directives, Blackfin: Blackfin Directives. (line 6) +* directives, M32R: M32R-Directives. (line 6) +* directives, M680x0: M68K-Directives. (line 6) +* directives, machine independent: Pseudo Ops. (line 6) +* directives, Xtensa: Xtensa Directives. (line 6) +* directives, Z8000: Z8000 Directives. (line 6) +* Disable floating-point instructions: MIPS floating-point. (line 6) +* Disable single-precision floating-point operations: MIPS floating-point. + (line 12) +* displacement sizing character, VAX: VAX-operands. (line 12) +* dollar local symbols: Symbol Names. (line 105) +* dot (symbol): Dot. (line 6) +* double directive: Double. (line 6) +* double directive, i386: i386-Float. (line 14) +* double directive, M680x0: M68K-Float. (line 14) +* double directive, M68HC11: M68HC11-Float. (line 14) +* double directive, TIC54X: TIC54X-Directives. (line 64) +* double directive, VAX: VAX-float. (line 15) +* double directive, x86-64: i386-Float. (line 14) +* doublequote (\"): Strings. (line 43) +* drlist directive, TIC54X: TIC54X-Directives. (line 73) +* drnolist directive, TIC54X: TIC54X-Directives. (line 73) +* dual directive, i860: Directives-i860. (line 6) +* ECOFF sections: MIPS Object. (line 6) +* ecr register, V850: V850-Regs. (line 113) +* eight-byte integer: Quad. (line 9) +* eipc register, V850: V850-Regs. (line 101) +* eipsw register, V850: V850-Regs. (line 104) +* eject directive: Eject. (line 6) +* ELF symbol type: Type. (line 22) +* else directive: Else. (line 6) +* elseif directive: Elseif. (line 6) +* empty expressions: Empty Exprs. (line 6) +* emsg directive, TIC54X: TIC54X-Directives. (line 77) +* emulation: Overview. (line 744) +* encoding options, i386: i386-Mnemonics. (line 32) +* encoding options, x86-64: i386-Mnemonics. (line 32) +* end directive: End. (line 6) +* enddual directive, i860: Directives-i860. (line 11) +* endef directive: Endef. (line 6) +* endfunc directive: Endfunc. (line 6) +* endianness, MIPS: Overview. (line 641) +* endianness, PJ: Overview. (line 548) +* endif directive: Endif. (line 6) +* endloop directive, TIC54X: TIC54X-Directives. (line 143) +* endm directive: Macro. (line 138) +* endm directive, TIC54X: TIC54X-Directives. (line 153) +* endstruct directive, TIC54X: TIC54X-Directives. (line 217) +* endunion directive, TIC54X: TIC54X-Directives. (line 251) +* environment settings, TIC54X: TIC54X-Env. (line 6) +* EOF, newline must precede: Statements. (line 13) +* ep register, V850: V850-Regs. (line 95) +* equ directive: Equ. (line 6) +* equ directive, TIC54X: TIC54X-Directives. (line 192) +* equiv directive: Equiv. (line 6) +* eqv directive: Eqv. (line 6) +* err directive: Err. (line 6) +* error directive: Error. (line 6) +* error messages: Errors. (line 6) +* error on valid input: Bug Criteria. (line 12) +* errors, caused by warnings: W. (line 16) +* errors, continuing after: Z. (line 6) +* ESA/390 floating point (IEEE): ESA/390 Floating Point. + (line 6) +* ESA/390 support: ESA/390-Dependent. (line 6) +* ESA/390 Syntax: ESA/390 Options. (line 8) +* ESA/390-only directives: ESA/390 Directives. (line 12) +* escape codes, character: Strings. (line 15) +* eval directive, TIC54X: TIC54X-Directives. (line 24) +* even: Z8000 Directives. (line 58) +* even directive, M680x0: M68K-Directives. (line 15) +* even directive, TIC54X: TIC54X-Directives. (line 6) +* exitm directive: Macro. (line 141) +* expr (internal section): As Sections. (line 17) +* expression arguments: Arguments. (line 6) +* expressions: Expressions. (line 6) +* expressions, comparison: Infix Ops. (line 55) +* expressions, empty: Empty Exprs. (line 6) +* expressions, integer: Integer Exprs. (line 6) +* extAuxRegister directive, ARC: ARC Directives. (line 18) +* extCondCode directive, ARC: ARC Directives. (line 41) +* extCoreRegister directive, ARC: ARC Directives. (line 53) +* extend directive M680x0: M68K-Float. (line 17) +* extend directive M68HC11: M68HC11-Float. (line 17) +* extended directive, i960: Directives-i960. (line 13) +* extern directive: Extern. (line 6) +* extInstruction directive, ARC: ARC Directives. (line 78) +* fail directive: Fail. (line 6) +* far_mode directive, TIC54X: TIC54X-Directives. (line 82) +* faster processing (-f): f. (line 6) +* fatal signal: Bug Criteria. (line 9) +* fclist directive, TIC54X: TIC54X-Directives. (line 87) +* fcnolist directive, TIC54X: TIC54X-Directives. (line 87) +* fepc register, V850: V850-Regs. (line 107) +* fepsw register, V850: V850-Regs. (line 110) +* ffloat directive, VAX: VAX-directives. (line 14) +* field directive, TIC54X: TIC54X-Directives. (line 91) +* file directive: File. (line 6) +* file directive, MSP 430: MSP430 Directives. (line 6) +* file name, logical: File. (line 13) +* files, including: Include. (line 6) +* files, input: Input Files. (line 6) +* fill directive: Fill. (line 6) +* filling memory <1>: Skip. (line 6) +* filling memory: Space. (line 6) +* FLIX syntax: Xtensa Syntax. (line 6) +* float directive: Float. (line 6) +* float directive, i386: i386-Float. (line 14) +* float directive, M680x0: M68K-Float. (line 11) +* float directive, M68HC11: M68HC11-Float. (line 11) +* float directive, TIC54X: TIC54X-Directives. (line 64) +* float directive, VAX: VAX-float. (line 15) +* float directive, x86-64: i386-Float. (line 14) +* floating point numbers: Flonums. (line 6) +* floating point numbers (double): Double. (line 6) +* floating point numbers (single) <1>: Float. (line 6) +* floating point numbers (single): Single. (line 6) +* floating point, Alpha (IEEE): Alpha Floating Point. + (line 6) +* floating point, ARC (IEEE): ARC Floating Point. (line 6) +* floating point, ARM (IEEE): ARM Floating Point. (line 6) +* floating point, D10V: D10V-Float. (line 6) +* floating point, D30V: D30V-Float. (line 6) +* floating point, ESA/390 (IEEE): ESA/390 Floating Point. + (line 6) +* floating point, H8/300 (IEEE): H8/300 Floating Point. + (line 6) +* floating point, HPPA (IEEE): HPPA Floating Point. (line 6) +* floating point, i386: i386-Float. (line 6) +* floating point, i960 (IEEE): Floating Point-i960. (line 6) +* floating point, M680x0: M68K-Float. (line 6) +* floating point, M68HC11: M68HC11-Float. (line 6) +* floating point, MSP 430 (IEEE): MSP430 Floating Point. + (line 6) +* floating point, s390: s390 Floating Point. (line 6) +* floating point, SH (IEEE): SH Floating Point. (line 6) +* floating point, SPARC (IEEE): Sparc-Float. (line 6) +* floating point, V850 (IEEE): V850 Floating Point. (line 6) +* floating point, VAX: VAX-float. (line 6) +* floating point, x86-64: i386-Float. (line 6) +* floating point, Z80: Z80 Floating Point. (line 6) +* flonums: Flonums. (line 6) +* format of error messages: Errors. (line 24) +* format of warning messages: Errors. (line 12) +* formfeed (\f): Strings. (line 18) +* func directive: Func. (line 6) +* functions, in expressions: Operators. (line 6) +* gbr960, i960 postprocessor: Options-i960. (line 40) +* gfloat directive, VAX: VAX-directives. (line 18) +* global: Z8000 Directives. (line 21) +* global directive: Global. (line 6) +* global directive, TIC54X: TIC54X-Directives. (line 103) +* gp register, MIPS: MIPS Object. (line 11) +* gp register, V850: V850-Regs. (line 17) +* grouping data: Sub-Sections. (line 6) +* H8/300 addressing modes: H8/300-Addressing. (line 6) +* H8/300 floating point (IEEE): H8/300 Floating Point. + (line 6) +* H8/300 line comment character: H8/300-Chars. (line 6) +* H8/300 line separator: H8/300-Chars. (line 8) +* H8/300 machine directives (none): H8/300 Directives. (line 6) +* H8/300 opcode summary: H8/300 Opcodes. (line 6) +* H8/300 options: H8/300 Options. (line 6) +* H8/300 registers: H8/300-Regs. (line 6) +* H8/300 size suffixes: H8/300 Opcodes. (line 163) +* H8/300 support: H8/300-Dependent. (line 6) +* H8/300H, assembling for: H8/300 Directives. (line 8) +* half directive, ARC: ARC Directives. (line 156) +* half directive, SPARC: Sparc-Directives. (line 17) +* half directive, TIC54X: TIC54X-Directives. (line 111) +* hex character code (\XD...): Strings. (line 36) +* hexadecimal integers: Integers. (line 15) +* hexadecimal prefix, Z80: Z80-Chars. (line 8) +* hfloat directive, VAX: VAX-directives. (line 22) +* hi pseudo-op, V850: V850 Opcodes. (line 33) +* hi0 pseudo-op, V850: V850 Opcodes. (line 10) +* hidden directive: Hidden. (line 6) +* high directive, M32R: M32R-Directives. (line 18) +* hilo pseudo-op, V850: V850 Opcodes. (line 55) +* HPPA directives not supported: HPPA Directives. (line 11) +* HPPA floating point (IEEE): HPPA Floating Point. (line 6) +* HPPA Syntax: HPPA Options. (line 8) +* HPPA-only directives: HPPA Directives. (line 24) +* hword directive: hword. (line 6) +* i370 support: ESA/390-Dependent. (line 6) +* i386 16-bit code: i386-16bit. (line 6) +* i386 arch directive: i386-Arch. (line 6) +* i386 att_syntax pseudo op: i386-Syntax. (line 6) +* i386 conversion instructions: i386-Mnemonics. (line 36) +* i386 floating point: i386-Float. (line 6) +* i386 immediate operands: i386-Syntax. (line 15) +* i386 instruction naming: i386-Mnemonics. (line 6) +* i386 instruction prefixes: i386-Prefixes. (line 6) +* i386 intel_syntax pseudo op: i386-Syntax. (line 6) +* i386 jump optimization: i386-Jumps. (line 6) +* i386 jump, call, return: i386-Syntax. (line 38) +* i386 jump/call operands: i386-Syntax. (line 15) +* i386 memory references: i386-Memory. (line 6) +* i386 mnemonic compatibility: i386-Mnemonics. (line 61) +* i386 mul, imul instructions: i386-Notes. (line 6) +* i386 options: i386-Options. (line 6) +* i386 register operands: i386-Syntax. (line 15) +* i386 registers: i386-Regs. (line 6) +* i386 sections: i386-Syntax. (line 44) +* i386 size suffixes: i386-Syntax. (line 29) +* i386 source, destination operands: i386-Syntax. (line 22) +* i386 support: i386-Dependent. (line 6) +* i386 syntax compatibility: i386-Syntax. (line 6) +* i80386 support: i386-Dependent. (line 6) +* i860 machine directives: Directives-i860. (line 6) +* i860 opcodes: Opcodes for i860. (line 6) +* i860 support: i860-Dependent. (line 6) +* i960 architecture options: Options-i960. (line 6) +* i960 branch recording: Options-i960. (line 22) +* i960 callj pseudo-opcode: callj-i960. (line 6) +* i960 compare and jump expansions: Compare-and-branch-i960. + (line 13) +* i960 compare/branch instructions: Compare-and-branch-i960. + (line 6) +* i960 floating point (IEEE): Floating Point-i960. (line 6) +* i960 machine directives: Directives-i960. (line 6) +* i960 opcodes: Opcodes for i960. (line 6) +* i960 options: Options-i960. (line 6) +* i960 support: i960-Dependent. (line 6) +* IA-64 line comment character: IA-64-Chars. (line 6) +* IA-64 line separator: IA-64-Chars. (line 8) +* IA-64 options: IA-64 Options. (line 6) +* IA-64 Processor-status-Register bit names: IA-64-Bits. (line 6) +* IA-64 registers: IA-64-Regs. (line 6) +* IA-64 support: IA-64-Dependent. (line 6) +* IA-64 Syntax: IA-64 Options. (line 96) +* ident directive: Ident. (line 6) +* identifiers, ARM: ARM-Chars. (line 15) +* identifiers, MSP 430: MSP430-Chars. (line 8) +* if directive: If. (line 6) +* ifb directive: If. (line 21) +* ifc directive: If. (line 25) +* ifdef directive: If. (line 16) +* ifeq directive: If. (line 33) +* ifeqs directive: If. (line 36) +* ifge directive: If. (line 40) +* ifgt directive: If. (line 44) +* ifle directive: If. (line 48) +* iflt directive: If. (line 52) +* ifnb directive: If. (line 56) +* ifnc directive: If. (line 61) +* ifndef directive: If. (line 65) +* ifne directive: If. (line 72) +* ifnes directive: If. (line 76) +* ifnotdef directive: If. (line 65) +* immediate character, ARM: ARM-Chars. (line 13) +* immediate character, M680x0: M68K-Chars. (line 6) +* immediate character, VAX: VAX-operands. (line 6) +* immediate fields, relaxation: Xtensa Immediate Relaxation. + (line 6) +* immediate operands, i386: i386-Syntax. (line 15) +* immediate operands, x86-64: i386-Syntax. (line 15) +* imul instruction, i386: i386-Notes. (line 6) +* imul instruction, x86-64: i386-Notes. (line 6) +* incbin directive: Incbin. (line 6) +* include directive: Include. (line 6) +* include directive search path: I. (line 6) +* indirect character, VAX: VAX-operands. (line 9) +* infix operators: Infix Ops. (line 6) +* inhibiting interrupts, i386: i386-Prefixes. (line 36) +* input: Input Files. (line 6) +* input file linenumbers: Input Files. (line 35) +* instruction aliases, s390: s390 Aliases. (line 6) +* instruction expansion, CRIS: CRIS-Expand. (line 6) +* instruction expansion, MMIX: MMIX-Expand. (line 6) +* instruction formats, s390: s390 Formats. (line 6) +* instruction marker, s390: s390 Instruction Marker. + (line 6) +* instruction mnemonics, s390: s390 Mnemonics. (line 6) +* instruction naming, i386: i386-Mnemonics. (line 6) +* instruction naming, x86-64: i386-Mnemonics. (line 6) +* instruction operand modifier, s390: s390 Operand Modifier. + (line 6) +* instruction operands, s390: s390 Operands. (line 6) +* instruction prefixes, i386: i386-Prefixes. (line 6) +* instruction set, M680x0: M68K-opcodes. (line 6) +* instruction set, M68HC11: M68HC11-opcodes. (line 6) +* instruction summary, AVR: AVR Opcodes. (line 6) +* instruction summary, D10V: D10V-Opcodes. (line 6) +* instruction summary, D30V: D30V-Opcodes. (line 6) +* instruction summary, H8/300: H8/300 Opcodes. (line 6) +* instruction summary, LM32: LM32 Opcodes. (line 6) +* instruction summary, SH: SH Opcodes. (line 6) +* instruction summary, SH64: SH64 Opcodes. (line 6) +* instruction summary, Z8000: Z8000 Opcodes. (line 6) +* instruction syntax, s390: s390 Syntax. (line 6) +* instructions and directives: Statements. (line 19) +* int directive: Int. (line 6) +* int directive, H8/300: H8/300 Directives. (line 6) +* int directive, i386: i386-Float. (line 21) +* int directive, TIC54X: TIC54X-Directives. (line 111) +* int directive, x86-64: i386-Float. (line 21) +* integer expressions: Integer Exprs. (line 6) +* integer, 16-byte: Octa. (line 6) +* integer, 8-byte: Quad. (line 9) +* integers: Integers. (line 6) +* integers, 16-bit: hword. (line 6) +* integers, 32-bit: Int. (line 6) +* integers, binary: Integers. (line 6) +* integers, decimal: Integers. (line 12) +* integers, hexadecimal: Integers. (line 15) +* integers, octal: Integers. (line 9) +* integers, one byte: Byte. (line 6) +* intel_syntax pseudo op, i386: i386-Syntax. (line 6) +* intel_syntax pseudo op, x86-64: i386-Syntax. (line 6) +* internal assembler sections: As Sections. (line 6) +* internal directive: Internal. (line 6) +* invalid input: Bug Criteria. (line 14) +* invocation summary: Overview. (line 6) +* IP2K architecture options: IP2K-Opts. (line 14) +* IP2K options: IP2K-Opts. (line 6) +* IP2K support: IP2K-Dependent. (line 6) +* irp directive: Irp. (line 6) +* irpc directive: Irpc. (line 6) +* ISA options, SH64: SH64 Options. (line 6) +* joining text and data sections: R. (line 6) +* jump instructions, i386: i386-Mnemonics. (line 55) +* jump instructions, x86-64: i386-Mnemonics. (line 55) +* jump optimization, i386: i386-Jumps. (line 6) +* jump optimization, x86-64: i386-Jumps. (line 6) +* jump/call operands, i386: i386-Syntax. (line 15) +* jump/call operands, x86-64: i386-Syntax. (line 15) +* L16SI instructions, relaxation: Xtensa Immediate Relaxation. + (line 23) +* L16UI instructions, relaxation: Xtensa Immediate Relaxation. + (line 23) +* L32I instructions, relaxation: Xtensa Immediate Relaxation. + (line 23) +* L8UI instructions, relaxation: Xtensa Immediate Relaxation. + (line 23) +* label (:): Statements. (line 30) +* label directive, TIC54X: TIC54X-Directives. (line 123) +* labels: Labels. (line 6) +* lcomm directive: Lcomm. (line 6) +* lcomm directive, COFF: i386-Directives. (line 6) +* ld: Object. (line 15) +* ldouble directive M680x0: M68K-Float. (line 17) +* ldouble directive M68HC11: M68HC11-Float. (line 17) +* ldouble directive, TIC54X: TIC54X-Directives. (line 64) +* LDR reg,=<label> pseudo op, ARM: ARM Opcodes. (line 15) +* leafproc directive, i960: Directives-i960. (line 18) +* length directive, TIC54X: TIC54X-Directives. (line 127) +* length of symbols: Symbol Intro. (line 14) +* lflags directive (ignored): Lflags. (line 6) +* line comment character: Comments. (line 19) +* line comment character, Alpha: Alpha-Chars. (line 6) +* line comment character, ARM: ARM-Chars. (line 6) +* line comment character, AVR: AVR-Chars. (line 6) +* line comment character, D10V: D10V-Chars. (line 6) +* line comment character, D30V: D30V-Chars. (line 6) +* line comment character, H8/300: H8/300-Chars. (line 6) +* line comment character, IA-64: IA-64-Chars. (line 6) +* line comment character, M680x0: M68K-Chars. (line 6) +* line comment character, MSP 430: MSP430-Chars. (line 6) +* line comment character, s390: s390 Characters. (line 6) +* line comment character, SH: SH-Chars. (line 6) +* line comment character, SH64: SH64-Chars. (line 6) +* line comment character, Sparc: Sparc-Chars. (line 6) +* line comment character, V850: V850-Chars. (line 6) +* line comment character, Z80: Z80-Chars. (line 6) +* line comment character, Z8000: Z8000-Chars. (line 6) +* line comment characters, CRIS: CRIS-Chars. (line 6) +* line comment characters, MMIX: MMIX-Chars. (line 6) +* line directive: Line. (line 6) +* line directive, MSP 430: MSP430 Directives. (line 14) +* line numbers, in input files: Input Files. (line 35) +* line numbers, in warnings/errors: Errors. (line 16) +* line separator character: Statements. (line 6) +* line separator, Alpha: Alpha-Chars. (line 8) +* line separator, ARM: ARM-Chars. (line 10) +* line separator, AVR: AVR-Chars. (line 10) +* line separator, H8/300: H8/300-Chars. (line 8) +* line separator, IA-64: IA-64-Chars. (line 8) +* line separator, SH: SH-Chars. (line 8) +* line separator, SH64: SH64-Chars. (line 8) +* line separator, Sparc: Sparc-Chars. (line 8) +* line separator, Z8000: Z8000-Chars. (line 8) +* lines starting with #: Comments. (line 39) +* linker: Object. (line 15) +* linker, and assembler: Secs Background. (line 10) +* linkonce directive: Linkonce. (line 6) +* list directive: List. (line 6) +* list directive, TIC54X: TIC54X-Directives. (line 131) +* listing control, turning off: Nolist. (line 6) +* listing control, turning on: List. (line 6) +* listing control: new page: Eject. (line 6) +* listing control: paper size: Psize. (line 6) +* listing control: subtitle: Sbttl. (line 6) +* listing control: title line: Title. (line 6) +* listings, enabling: a. (line 6) +* literal directive: Literal Directive. (line 6) +* literal pool entries, s390: s390 Literal Pool Entries. + (line 6) +* literal_position directive: Literal Position Directive. + (line 6) +* literal_prefix directive: Literal Prefix Directive. + (line 6) +* little endian output, MIPS: Overview. (line 644) +* little endian output, PJ: Overview. (line 551) +* little-endian output, MIPS: MIPS Opts. (line 13) +* LM32 modifiers: LM32-Modifiers. (line 6) +* LM32 opcode summary: LM32 Opcodes. (line 6) +* LM32 options (none): LM32 Options. (line 6) +* LM32 register names: LM32-Regs. (line 6) +* LM32 support: LM32-Dependent. (line 6) +* ln directive: Ln. (line 6) +* lo pseudo-op, V850: V850 Opcodes. (line 22) +* loc directive: Loc. (line 6) +* loc_mark_labels directive: Loc_mark_labels. (line 6) +* local common symbols: Lcomm. (line 6) +* local directive: Local. (line 6) +* local labels: Symbol Names. (line 35) +* local symbol names: Symbol Names. (line 22) +* local symbols, retaining in output: L. (line 6) +* location counter: Dot. (line 6) +* location counter, advancing: Org. (line 6) +* location counter, Z80: Z80-Chars. (line 8) +* logical file name: File. (line 13) +* logical line number: Line. (line 6) +* logical line numbers: Comments. (line 39) +* long directive: Long. (line 6) +* long directive, ARC: ARC Directives. (line 159) +* long directive, i386: i386-Float. (line 21) +* long directive, TIC54X: TIC54X-Directives. (line 135) +* long directive, x86-64: i386-Float. (line 21) +* longcall pseudo-op, V850: V850 Opcodes. (line 123) +* longcalls directive: Longcalls Directive. (line 6) +* longjump pseudo-op, V850: V850 Opcodes. (line 129) +* loop directive, TIC54X: TIC54X-Directives. (line 143) +* LOOP instructions, alignment: Xtensa Automatic Alignment. + (line 6) +* low directive, M32R: M32R-Directives. (line 9) +* lp register, V850: V850-Regs. (line 98) +* lval: Z8000 Directives. (line 27) +* M16C architecture option: M32C-Opts. (line 12) +* M32C architecture option: M32C-Opts. (line 9) +* M32C modifiers: M32C-Modifiers. (line 6) +* M32C options: M32C-Opts. (line 6) +* M32C support: M32C-Dependent. (line 6) +* M32R architecture options: M32R-Opts. (line 9) +* M32R directives: M32R-Directives. (line 6) +* M32R options: M32R-Opts. (line 6) +* M32R support: M32R-Dependent. (line 6) +* M32R warnings: M32R-Warnings. (line 6) +* M680x0 addressing modes: M68K-Syntax. (line 21) +* M680x0 architecture options: M68K-Opts. (line 104) +* M680x0 branch improvement: M68K-Branch. (line 6) +* M680x0 directives: M68K-Directives. (line 6) +* M680x0 floating point: M68K-Float. (line 6) +* M680x0 immediate character: M68K-Chars. (line 6) +* M680x0 line comment character: M68K-Chars. (line 6) +* M680x0 opcodes: M68K-opcodes. (line 6) +* M680x0 options: M68K-Opts. (line 6) +* M680x0 pseudo-opcodes: M68K-Branch. (line 6) +* M680x0 size modifiers: M68K-Syntax. (line 8) +* M680x0 support: M68K-Dependent. (line 6) +* M680x0 syntax: M68K-Syntax. (line 8) +* M68HC11 addressing modes: M68HC11-Syntax. (line 17) +* M68HC11 and M68HC12 support: M68HC11-Dependent. (line 6) +* M68HC11 assembler directive .far: M68HC11-Directives. (line 20) +* M68HC11 assembler directive .interrupt: M68HC11-Directives. (line 26) +* M68HC11 assembler directive .mode: M68HC11-Directives. (line 16) +* M68HC11 assembler directive .relax: M68HC11-Directives. (line 10) +* M68HC11 assembler directive .xrefb: M68HC11-Directives. (line 31) +* M68HC11 assembler directives: M68HC11-Directives. (line 6) +* M68HC11 branch improvement: M68HC11-Branch. (line 6) +* M68HC11 floating point: M68HC11-Float. (line 6) +* M68HC11 modifiers: M68HC11-Modifiers. (line 6) +* M68HC11 opcodes: M68HC11-opcodes. (line 6) +* M68HC11 options: M68HC11-Opts. (line 6) +* M68HC11 pseudo-opcodes: M68HC11-Branch. (line 6) +* M68HC11 syntax: M68HC11-Syntax. (line 6) +* M68HC12 assembler directives: M68HC11-Directives. (line 6) +* machine dependencies: Machine Dependencies. + (line 6) +* machine directives, ARC: ARC Directives. (line 6) +* machine directives, ARM: ARM Directives. (line 6) +* machine directives, H8/300 (none): H8/300 Directives. (line 6) +* machine directives, i860: Directives-i860. (line 6) +* machine directives, i960: Directives-i960. (line 6) +* machine directives, MSP 430: MSP430 Directives. (line 6) +* machine directives, SH: SH Directives. (line 6) +* machine directives, SH64: SH64 Directives. (line 9) +* machine directives, SPARC: Sparc-Directives. (line 6) +* machine directives, TIC54X: TIC54X-Directives. (line 6) +* machine directives, V850: V850 Directives. (line 6) +* machine directives, VAX: VAX-directives. (line 6) +* machine directives, x86: i386-Directives. (line 6) +* machine independent directives: Pseudo Ops. (line 6) +* machine instructions (not covered): Manual. (line 14) +* machine-independent syntax: Syntax. (line 6) +* macro directive: Macro. (line 28) +* macro directive, TIC54X: TIC54X-Directives. (line 153) +* macros: Macro. (line 6) +* macros, count executed: Macro. (line 143) +* Macros, MSP 430: MSP430-Macros. (line 6) +* macros, TIC54X: TIC54X-Macros. (line 6) +* make rules: MD. (line 6) +* manual, structure and purpose: Manual. (line 6) +* math builtins, TIC54X: TIC54X-Builtins. (line 6) +* Maximum number of continuation lines: listing. (line 34) +* memory references, i386: i386-Memory. (line 6) +* memory references, x86-64: i386-Memory. (line 6) +* memory-mapped registers, TIC54X: TIC54X-MMRegs. (line 6) +* merging text and data sections: R. (line 6) +* messages from assembler: Errors. (line 6) +* MicroBlaze architectures: MicroBlaze-Dependent. + (line 6) +* MicroBlaze directives: MicroBlaze Directives. + (line 6) +* MicroBlaze support: MicroBlaze-Dependent. + (line 13) +* minus, permitted arguments: Infix Ops. (line 49) +* MIPS architecture options: MIPS Opts. (line 29) +* MIPS big-endian output: MIPS Opts. (line 13) +* MIPS CPU override: MIPS ISA. (line 18) +* MIPS debugging directives: MIPS Stabs. (line 6) +* MIPS DSP Release 1 instruction generation override: MIPS ASE instruction generation overrides. + (line 21) +* MIPS DSP Release 2 instruction generation override: MIPS ASE instruction generation overrides. + (line 26) +* MIPS ECOFF sections: MIPS Object. (line 6) +* MIPS endianness: Overview. (line 641) +* MIPS ISA: Overview. (line 647) +* MIPS ISA override: MIPS ISA. (line 6) +* MIPS little-endian output: MIPS Opts. (line 13) +* MIPS MDMX instruction generation override: MIPS ASE instruction generation overrides. + (line 16) +* MIPS MIPS-3D instruction generation override: MIPS ASE instruction generation overrides. + (line 6) +* MIPS MT instruction generation override: MIPS ASE instruction generation overrides. + (line 32) +* MIPS option stack: MIPS option stack. (line 6) +* MIPS processor: MIPS-Dependent. (line 6) +* MIT: M68K-Syntax. (line 6) +* mlib directive, TIC54X: TIC54X-Directives. (line 159) +* mlist directive, TIC54X: TIC54X-Directives. (line 164) +* MMIX assembler directive BSPEC: MMIX-Pseudos. (line 131) +* MMIX assembler directive BYTE: MMIX-Pseudos. (line 97) +* MMIX assembler directive ESPEC: MMIX-Pseudos. (line 131) +* MMIX assembler directive GREG: MMIX-Pseudos. (line 50) +* MMIX assembler directive IS: MMIX-Pseudos. (line 42) +* MMIX assembler directive LOC: MMIX-Pseudos. (line 7) +* MMIX assembler directive LOCAL: MMIX-Pseudos. (line 28) +* MMIX assembler directive OCTA: MMIX-Pseudos. (line 108) +* MMIX assembler directive PREFIX: MMIX-Pseudos. (line 120) +* MMIX assembler directive TETRA: MMIX-Pseudos. (line 108) +* MMIX assembler directive WYDE: MMIX-Pseudos. (line 108) +* MMIX assembler directives: MMIX-Pseudos. (line 6) +* MMIX line comment characters: MMIX-Chars. (line 6) +* MMIX options: MMIX-Opts. (line 6) +* MMIX pseudo-op BSPEC: MMIX-Pseudos. (line 131) +* MMIX pseudo-op BYTE: MMIX-Pseudos. (line 97) +* MMIX pseudo-op ESPEC: MMIX-Pseudos. (line 131) +* MMIX pseudo-op GREG: MMIX-Pseudos. (line 50) +* MMIX pseudo-op IS: MMIX-Pseudos. (line 42) +* MMIX pseudo-op LOC: MMIX-Pseudos. (line 7) +* MMIX pseudo-op LOCAL: MMIX-Pseudos. (line 28) +* MMIX pseudo-op OCTA: MMIX-Pseudos. (line 108) +* MMIX pseudo-op PREFIX: MMIX-Pseudos. (line 120) +* MMIX pseudo-op TETRA: MMIX-Pseudos. (line 108) +* MMIX pseudo-op WYDE: MMIX-Pseudos. (line 108) +* MMIX pseudo-ops: MMIX-Pseudos. (line 6) +* MMIX register names: MMIX-Regs. (line 6) +* MMIX support: MMIX-Dependent. (line 6) +* mmixal differences: MMIX-mmixal. (line 6) +* mmregs directive, TIC54X: TIC54X-Directives. (line 170) +* mmsg directive, TIC54X: TIC54X-Directives. (line 77) +* MMX, i386: i386-SIMD. (line 6) +* MMX, x86-64: i386-SIMD. (line 6) +* mnemonic compatibility, i386: i386-Mnemonics. (line 61) +* mnemonic suffixes, i386: i386-Syntax. (line 29) +* mnemonic suffixes, x86-64: i386-Syntax. (line 29) +* mnemonics for opcodes, VAX: VAX-opcodes. (line 6) +* mnemonics, AVR: AVR Opcodes. (line 6) +* mnemonics, D10V: D10V-Opcodes. (line 6) +* mnemonics, D30V: D30V-Opcodes. (line 6) +* mnemonics, H8/300: H8/300 Opcodes. (line 6) +* mnemonics, LM32: LM32 Opcodes. (line 6) +* mnemonics, SH: SH Opcodes. (line 6) +* mnemonics, SH64: SH64 Opcodes. (line 6) +* mnemonics, Z8000: Z8000 Opcodes. (line 6) +* mnolist directive, TIC54X: TIC54X-Directives. (line 164) +* Motorola syntax for the 680x0: M68K-Moto-Syntax. (line 6) +* MOVI instructions, relaxation: Xtensa Immediate Relaxation. + (line 12) +* MOVW and MOVT relocations, ARM: ARM-Relocations. (line 20) +* MRI compatibility mode: M. (line 6) +* mri directive: MRI. (line 6) +* MRI mode, temporarily: MRI. (line 6) +* MSP 430 floating point (IEEE): MSP430 Floating Point. + (line 6) +* MSP 430 identifiers: MSP430-Chars. (line 8) +* MSP 430 line comment character: MSP430-Chars. (line 6) +* MSP 430 machine directives: MSP430 Directives. (line 6) +* MSP 430 macros: MSP430-Macros. (line 6) +* MSP 430 opcodes: MSP430 Opcodes. (line 6) +* MSP 430 options (none): MSP430 Options. (line 6) +* MSP 430 profiling capability: MSP430 Profiling Capability. + (line 6) +* MSP 430 register names: MSP430-Regs. (line 6) +* MSP 430 support: MSP430-Dependent. (line 6) +* MSP430 Assembler Extensions: MSP430-Ext. (line 6) +* mul instruction, i386: i386-Notes. (line 6) +* mul instruction, x86-64: i386-Notes. (line 6) +* name: Z8000 Directives. (line 18) +* named section: Section. (line 6) +* named sections: Ld Sections. (line 8) +* names, symbol: Symbol Names. (line 6) +* naming object file: o. (line 6) +* new page, in listings: Eject. (line 6) +* newblock directive, TIC54X: TIC54X-Directives. (line 176) +* newline (\n): Strings. (line 21) +* newline, required at file end: Statements. (line 13) +* no-absolute-literals directive: Absolute Literals Directive. + (line 6) +* no-longcalls directive: Longcalls Directive. (line 6) +* no-schedule directive: Schedule Directive. (line 6) +* no-transform directive: Transform Directive. (line 6) +* nolist directive: Nolist. (line 6) +* nolist directive, TIC54X: TIC54X-Directives. (line 131) +* NOP pseudo op, ARM: ARM Opcodes. (line 9) +* notes for Alpha: Alpha Notes. (line 6) +* null-terminated strings: Asciz. (line 6) +* number constants: Numbers. (line 6) +* number of macros executed: Macro. (line 143) +* numbered subsections: Sub-Sections. (line 6) +* numbers, 16-bit: hword. (line 6) +* numeric values: Expressions. (line 6) +* nword directive, SPARC: Sparc-Directives. (line 20) +* object attributes: Object Attributes. (line 6) +* object file: Object. (line 6) +* object file format: Object Formats. (line 6) +* object file name: o. (line 6) +* object file, after errors: Z. (line 6) +* obsolescent directives: Deprecated. (line 6) +* octa directive: Octa. (line 6) +* octal character code (\DDD): Strings. (line 30) +* octal integers: Integers. (line 9) +* offset directive, V850: V850 Directives. (line 6) +* opcode mnemonics, VAX: VAX-opcodes. (line 6) +* opcode names, Xtensa: Xtensa Opcodes. (line 6) +* opcode summary, AVR: AVR Opcodes. (line 6) +* opcode summary, D10V: D10V-Opcodes. (line 6) +* opcode summary, D30V: D30V-Opcodes. (line 6) +* opcode summary, H8/300: H8/300 Opcodes. (line 6) +* opcode summary, LM32: LM32 Opcodes. (line 6) +* opcode summary, SH: SH Opcodes. (line 6) +* opcode summary, SH64: SH64 Opcodes. (line 6) +* opcode summary, Z8000: Z8000 Opcodes. (line 6) +* opcodes for ARC: ARC Opcodes. (line 6) +* opcodes for ARM: ARM Opcodes. (line 6) +* opcodes for MSP 430: MSP430 Opcodes. (line 6) +* opcodes for V850: V850 Opcodes. (line 6) +* opcodes, i860: Opcodes for i860. (line 6) +* opcodes, i960: Opcodes for i960. (line 6) +* opcodes, M680x0: M68K-opcodes. (line 6) +* opcodes, M68HC11: M68HC11-opcodes. (line 6) +* operand delimiters, i386: i386-Syntax. (line 15) +* operand delimiters, x86-64: i386-Syntax. (line 15) +* operand notation, VAX: VAX-operands. (line 6) +* operands in expressions: Arguments. (line 6) +* operator precedence: Infix Ops. (line 11) +* operators, in expressions: Operators. (line 6) +* operators, permitted arguments: Infix Ops. (line 6) +* optimization, D10V: Overview. (line 420) +* optimization, D30V: Overview. (line 425) +* optimizations: Xtensa Optimizations. + (line 6) +* option directive, ARC: ARC Directives. (line 162) +* option directive, TIC54X: TIC54X-Directives. (line 180) +* option summary: Overview. (line 6) +* options for Alpha: Alpha Options. (line 6) +* options for ARC (none): ARC Options. (line 6) +* options for ARM (none): ARM Options. (line 6) +* options for AVR (none): AVR Options. (line 6) +* options for Blackfin (none): Blackfin Options. (line 6) +* options for i386: i386-Options. (line 6) +* options for IA-64: IA-64 Options. (line 6) +* options for LM32 (none): LM32 Options. (line 6) +* options for MSP430 (none): MSP430 Options. (line 6) +* options for PDP-11: PDP-11-Options. (line 6) +* options for PowerPC: PowerPC-Opts. (line 6) +* options for s390: s390 Options. (line 6) +* options for SCORE: SCORE-Opts. (line 6) +* options for SPARC: Sparc-Opts. (line 6) +* options for V850 (none): V850 Options. (line 6) +* options for VAX/VMS: VAX-Opts. (line 42) +* options for x86-64: i386-Options. (line 6) +* options for Z80: Z80 Options. (line 6) +* options, all versions of assembler: Invoking. (line 6) +* options, command line: Command Line. (line 13) +* options, CRIS: CRIS-Opts. (line 6) +* options, D10V: D10V-Opts. (line 6) +* options, D30V: D30V-Opts. (line 6) +* options, H8/300: H8/300 Options. (line 6) +* options, i960: Options-i960. (line 6) +* options, IP2K: IP2K-Opts. (line 6) +* options, M32C: M32C-Opts. (line 6) +* options, M32R: M32R-Opts. (line 6) +* options, M680x0: M68K-Opts. (line 6) +* options, M68HC11: M68HC11-Opts. (line 6) +* options, MMIX: MMIX-Opts. (line 6) +* options, PJ: PJ Options. (line 6) +* options, SH: SH Options. (line 6) +* options, SH64: SH64 Options. (line 6) +* options, TIC54X: TIC54X-Opts. (line 6) +* options, Z8000: Z8000 Options. (line 6) +* org directive: Org. (line 6) +* other attribute, of a.out symbol: Symbol Other. (line 6) +* output file: Object. (line 6) +* p2align directive: P2align. (line 6) +* p2alignl directive: P2align. (line 28) +* p2alignw directive: P2align. (line 28) +* padding the location counter: Align. (line 6) +* padding the location counter given a power of two: P2align. (line 6) +* padding the location counter given number of bytes: Balign. (line 6) +* page, in listings: Eject. (line 6) +* paper size, for listings: Psize. (line 6) +* paths for .include: I. (line 6) +* patterns, writing in memory: Fill. (line 6) +* PDP-11 comments: PDP-11-Syntax. (line 16) +* PDP-11 floating-point register syntax: PDP-11-Syntax. (line 13) +* PDP-11 general-purpose register syntax: PDP-11-Syntax. (line 10) +* PDP-11 instruction naming: PDP-11-Mnemonics. (line 6) +* PDP-11 support: PDP-11-Dependent. (line 6) +* PDP-11 syntax: PDP-11-Syntax. (line 6) +* PIC code generation for ARM: ARM Options. (line 139) +* PIC code generation for M32R: M32R-Opts. (line 42) +* PIC selection, MIPS: MIPS Opts. (line 21) +* PJ endianness: Overview. (line 548) +* PJ options: PJ Options. (line 6) +* PJ support: PJ-Dependent. (line 6) +* plus, permitted arguments: Infix Ops. (line 44) +* popsection directive: PopSection. (line 6) +* Position-independent code, CRIS: CRIS-Opts. (line 27) +* Position-independent code, symbols in, CRIS: CRIS-Pic. (line 6) +* PowerPC architectures: PowerPC-Opts. (line 6) +* PowerPC directives: PowerPC-Pseudo. (line 6) +* PowerPC options: PowerPC-Opts. (line 6) +* PowerPC support: PPC-Dependent. (line 6) +* precedence of operators: Infix Ops. (line 11) +* precision, floating point: Flonums. (line 6) +* prefix operators: Prefix Ops. (line 6) +* prefixes, i386: i386-Prefixes. (line 6) +* preprocessing: Preprocessing. (line 6) +* preprocessing, turning on and off: Preprocessing. (line 27) +* previous directive: Previous. (line 6) +* primary attributes, COFF symbols: COFF Symbols. (line 13) +* print directive: Print. (line 6) +* proc directive, SPARC: Sparc-Directives. (line 25) +* profiler directive, MSP 430: MSP430 Directives. (line 22) +* profiling capability for MSP 430: MSP430 Profiling Capability. + (line 6) +* protected directive: Protected. (line 6) +* pseudo-op .arch, CRIS: CRIS-Pseudos. (line 45) +* pseudo-op .dword, CRIS: CRIS-Pseudos. (line 12) +* pseudo-op .syntax, CRIS: CRIS-Pseudos. (line 17) +* pseudo-op BSPEC, MMIX: MMIX-Pseudos. (line 131) +* pseudo-op BYTE, MMIX: MMIX-Pseudos. (line 97) +* pseudo-op ESPEC, MMIX: MMIX-Pseudos. (line 131) +* pseudo-op GREG, MMIX: MMIX-Pseudos. (line 50) +* pseudo-op IS, MMIX: MMIX-Pseudos. (line 42) +* pseudo-op LOC, MMIX: MMIX-Pseudos. (line 7) +* pseudo-op LOCAL, MMIX: MMIX-Pseudos. (line 28) +* pseudo-op OCTA, MMIX: MMIX-Pseudos. (line 108) +* pseudo-op PREFIX, MMIX: MMIX-Pseudos. (line 120) +* pseudo-op TETRA, MMIX: MMIX-Pseudos. (line 108) +* pseudo-op WYDE, MMIX: MMIX-Pseudos. (line 108) +* pseudo-opcodes, M680x0: M68K-Branch. (line 6) +* pseudo-opcodes, M68HC11: M68HC11-Branch. (line 6) +* pseudo-ops for branch, VAX: VAX-branch. (line 6) +* pseudo-ops, CRIS: CRIS-Pseudos. (line 6) +* pseudo-ops, machine independent: Pseudo Ops. (line 6) +* pseudo-ops, MMIX: MMIX-Pseudos. (line 6) +* psize directive: Psize. (line 6) +* PSR bits: IA-64-Bits. (line 6) +* pstring directive, TIC54X: TIC54X-Directives. (line 209) +* psw register, V850: V850-Regs. (line 116) +* purgem directive: Purgem. (line 6) +* purpose of GNU assembler: GNU Assembler. (line 12) +* pushsection directive: PushSection. (line 6) +* quad directive: Quad. (line 6) +* quad directive, i386: i386-Float. (line 21) +* quad directive, x86-64: i386-Float. (line 21) +* real-mode code, i386: i386-16bit. (line 6) +* ref directive, TIC54X: TIC54X-Directives. (line 103) +* register directive, SPARC: Sparc-Directives. (line 29) +* register names, Alpha: Alpha-Regs. (line 6) +* register names, ARC: ARC-Regs. (line 6) +* register names, ARM: ARM-Regs. (line 6) +* register names, AVR: AVR-Regs. (line 6) +* register names, CRIS: CRIS-Regs. (line 6) +* register names, H8/300: H8/300-Regs. (line 6) +* register names, IA-64: IA-64-Regs. (line 6) +* register names, LM32: LM32-Regs. (line 6) +* register names, MMIX: MMIX-Regs. (line 6) +* register names, MSP 430: MSP430-Regs. (line 6) +* register names, Sparc: Sparc-Regs. (line 6) +* register names, V850: V850-Regs. (line 6) +* register names, VAX: VAX-operands. (line 17) +* register names, Xtensa: Xtensa Registers. (line 6) +* register names, Z80: Z80-Regs. (line 6) +* register naming, s390: s390 Register. (line 6) +* register operands, i386: i386-Syntax. (line 15) +* register operands, x86-64: i386-Syntax. (line 15) +* registers, D10V: D10V-Regs. (line 6) +* registers, D30V: D30V-Regs. (line 6) +* registers, i386: i386-Regs. (line 6) +* registers, SH: SH-Regs. (line 6) +* registers, SH64: SH64-Regs. (line 6) +* registers, TIC54X memory-mapped: TIC54X-MMRegs. (line 6) +* registers, x86-64: i386-Regs. (line 6) +* registers, Z8000: Z8000-Regs. (line 6) +* relaxation: Xtensa Relaxation. (line 6) +* relaxation of ADDI instructions: Xtensa Immediate Relaxation. + (line 43) +* relaxation of branch instructions: Xtensa Branch Relaxation. + (line 6) +* relaxation of call instructions: Xtensa Call Relaxation. + (line 6) +* relaxation of immediate fields: Xtensa Immediate Relaxation. + (line 6) +* relaxation of L16SI instructions: Xtensa Immediate Relaxation. + (line 23) +* relaxation of L16UI instructions: Xtensa Immediate Relaxation. + (line 23) +* relaxation of L32I instructions: Xtensa Immediate Relaxation. + (line 23) +* relaxation of L8UI instructions: Xtensa Immediate Relaxation. + (line 23) +* relaxation of MOVI instructions: Xtensa Immediate Relaxation. + (line 12) +* reloc directive: Reloc. (line 6) +* relocation: Sections. (line 6) +* relocation example: Ld Sections. (line 40) +* relocations, Alpha: Alpha-Relocs. (line 6) +* relocations, Sparc: Sparc-Relocs. (line 6) +* repeat prefixes, i386: i386-Prefixes. (line 44) +* reporting bugs in assembler: Reporting Bugs. (line 6) +* rept directive: Rept. (line 6) +* reserve directive, SPARC: Sparc-Directives. (line 39) +* return instructions, i386: i386-Syntax. (line 38) +* return instructions, x86-64: i386-Syntax. (line 38) +* REX prefixes, i386: i386-Prefixes. (line 46) +* rsect: Z8000 Directives. (line 52) +* s390 floating point: s390 Floating Point. (line 6) +* s390 instruction aliases: s390 Aliases. (line 6) +* s390 instruction formats: s390 Formats. (line 6) +* s390 instruction marker: s390 Instruction Marker. + (line 6) +* s390 instruction mnemonics: s390 Mnemonics. (line 6) +* s390 instruction operand modifier: s390 Operand Modifier. + (line 6) +* s390 instruction operands: s390 Operands. (line 6) +* s390 instruction syntax: s390 Syntax. (line 6) +* s390 line comment character: s390 Characters. (line 6) +* s390 literal pool entries: s390 Literal Pool Entries. + (line 6) +* s390 options: s390 Options. (line 6) +* s390 register naming: s390 Register. (line 6) +* s390 support: S/390-Dependent. (line 6) +* sblock directive, TIC54X: TIC54X-Directives. (line 183) +* sbttl directive: Sbttl. (line 6) +* schedule directive: Schedule Directive. (line 6) +* scl directive: Scl. (line 6) +* SCORE architectures: SCORE-Opts. (line 6) +* SCORE directives: SCORE-Pseudo. (line 6) +* SCORE options: SCORE-Opts. (line 6) +* SCORE processor: SCORE-Dependent. (line 6) +* sdaoff pseudo-op, V850: V850 Opcodes. (line 65) +* search path for .include: I. (line 6) +* sect directive, MSP 430: MSP430 Directives. (line 18) +* sect directive, TIC54X: TIC54X-Directives. (line 189) +* section directive (COFF version): Section. (line 16) +* section directive (ELF version): Section. (line 70) +* section directive, V850: V850 Directives. (line 9) +* section override prefixes, i386: i386-Prefixes. (line 23) +* Section Stack <1>: Section. (line 65) +* Section Stack <2>: SubSection. (line 6) +* Section Stack <3>: PopSection. (line 6) +* Section Stack <4>: PushSection. (line 6) +* Section Stack: Previous. (line 6) +* section-relative addressing: Secs Background. (line 68) +* sections: Sections. (line 6) +* sections in messages, internal: As Sections. (line 6) +* sections, i386: i386-Syntax. (line 44) +* sections, named: Ld Sections. (line 8) +* sections, x86-64: i386-Syntax. (line 44) +* seg directive, SPARC: Sparc-Directives. (line 44) +* segm: Z8000 Directives. (line 10) +* set directive: Set. (line 6) +* set directive, TIC54X: TIC54X-Directives. (line 192) +* SH addressing modes: SH-Addressing. (line 6) +* SH floating point (IEEE): SH Floating Point. (line 6) +* SH line comment character: SH-Chars. (line 6) +* SH line separator: SH-Chars. (line 8) +* SH machine directives: SH Directives. (line 6) +* SH opcode summary: SH Opcodes. (line 6) +* SH options: SH Options. (line 6) +* SH registers: SH-Regs. (line 6) +* SH support: SH-Dependent. (line 6) +* SH64 ABI options: SH64 Options. (line 29) +* SH64 addressing modes: SH64-Addressing. (line 6) +* SH64 ISA options: SH64 Options. (line 6) +* SH64 line comment character: SH64-Chars. (line 6) +* SH64 line separator: SH64-Chars. (line 8) +* SH64 machine directives: SH64 Directives. (line 9) +* SH64 opcode summary: SH64 Opcodes. (line 6) +* SH64 options: SH64 Options. (line 6) +* SH64 registers: SH64-Regs. (line 6) +* SH64 support: SH64-Dependent. (line 6) +* shigh directive, M32R: M32R-Directives. (line 26) +* short directive: Short. (line 6) +* short directive, ARC: ARC Directives. (line 171) +* short directive, TIC54X: TIC54X-Directives. (line 111) +* SIMD, i386: i386-SIMD. (line 6) +* SIMD, x86-64: i386-SIMD. (line 6) +* single character constant: Chars. (line 6) +* single directive: Single. (line 6) +* single directive, i386: i386-Float. (line 14) +* single directive, x86-64: i386-Float. (line 14) +* single quote, Z80: Z80-Chars. (line 13) +* sixteen bit integers: hword. (line 6) +* sixteen byte integer: Octa. (line 6) +* size directive (COFF version): Size. (line 11) +* size directive (ELF version): Size. (line 19) +* size modifiers, D10V: D10V-Size. (line 6) +* size modifiers, D30V: D30V-Size. (line 6) +* size modifiers, M680x0: M68K-Syntax. (line 8) +* size prefixes, i386: i386-Prefixes. (line 27) +* size suffixes, H8/300: H8/300 Opcodes. (line 163) +* size, translations, Sparc: Sparc-Size-Translations. + (line 6) +* sizes operands, i386: i386-Syntax. (line 29) +* sizes operands, x86-64: i386-Syntax. (line 29) +* skip directive: Skip. (line 6) +* skip directive, M680x0: M68K-Directives. (line 19) +* skip directive, SPARC: Sparc-Directives. (line 48) +* sleb128 directive: Sleb128. (line 6) +* small objects, MIPS ECOFF: MIPS Object. (line 11) +* SmartMIPS instruction generation override: MIPS ASE instruction generation overrides. + (line 11) +* SOM symbol attributes: SOM Symbols. (line 6) +* source program: Input Files. (line 6) +* source, destination operands; i386: i386-Syntax. (line 22) +* source, destination operands; x86-64: i386-Syntax. (line 22) +* sp register: Xtensa Registers. (line 6) +* sp register, V850: V850-Regs. (line 14) +* space directive: Space. (line 6) +* space directive, TIC54X: TIC54X-Directives. (line 197) +* space used, maximum for assembly: statistics. (line 6) +* SPARC architectures: Sparc-Opts. (line 6) +* Sparc constants: Sparc-Constants. (line 6) +* SPARC data alignment: Sparc-Aligned-Data. (line 6) +* SPARC floating point (IEEE): Sparc-Float. (line 6) +* Sparc line comment character: Sparc-Chars. (line 6) +* Sparc line separator: Sparc-Chars. (line 8) +* SPARC machine directives: Sparc-Directives. (line 6) +* SPARC options: Sparc-Opts. (line 6) +* Sparc registers: Sparc-Regs. (line 6) +* Sparc relocations: Sparc-Relocs. (line 6) +* Sparc size translations: Sparc-Size-Translations. + (line 6) +* SPARC support: Sparc-Dependent. (line 6) +* SPARC syntax: Sparc-Aligned-Data. (line 21) +* special characters, ARC: ARC-Chars. (line 6) +* special characters, M680x0: M68K-Chars. (line 6) +* special purpose registers, MSP 430: MSP430-Regs. (line 11) +* sslist directive, TIC54X: TIC54X-Directives. (line 204) +* ssnolist directive, TIC54X: TIC54X-Directives. (line 204) +* stabd directive: Stab. (line 38) +* stabn directive: Stab. (line 48) +* stabs directive: Stab. (line 51) +* stabX directives: Stab. (line 6) +* standard assembler sections: Secs Background. (line 27) +* standard input, as input file: Command Line. (line 10) +* statement separator character: Statements. (line 6) +* statement separator, Alpha: Alpha-Chars. (line 8) +* statement separator, ARM: ARM-Chars. (line 10) +* statement separator, AVR: AVR-Chars. (line 10) +* statement separator, H8/300: H8/300-Chars. (line 8) +* statement separator, IA-64: IA-64-Chars. (line 8) +* statement separator, SH: SH-Chars. (line 8) +* statement separator, SH64: SH64-Chars. (line 8) +* statement separator, Sparc: Sparc-Chars. (line 8) +* statement separator, Z8000: Z8000-Chars. (line 8) +* statements, structure of: Statements. (line 6) +* statistics, about assembly: statistics. (line 6) +* stopping the assembly: Abort. (line 6) +* string constants: Strings. (line 6) +* string directive: String. (line 8) +* string directive on HPPA: HPPA Directives. (line 137) +* string directive, TIC54X: TIC54X-Directives. (line 209) +* string literals: Ascii. (line 6) +* string, copying to object file: String. (line 8) +* string16 directive: String. (line 8) +* string16, copying to object file: String. (line 8) +* string32 directive: String. (line 8) +* string32, copying to object file: String. (line 8) +* string64 directive: String. (line 8) +* string64, copying to object file: String. (line 8) +* string8 directive: String. (line 8) +* string8, copying to object file: String. (line 8) +* struct directive: Struct. (line 6) +* struct directive, TIC54X: TIC54X-Directives. (line 217) +* structure debugging, COFF: Tag. (line 6) +* sub-instruction ordering, D10V: D10V-Chars. (line 6) +* sub-instruction ordering, D30V: D30V-Chars. (line 6) +* sub-instructions, D10V: D10V-Subs. (line 6) +* sub-instructions, D30V: D30V-Subs. (line 6) +* subexpressions: Arguments. (line 24) +* subsection directive: SubSection. (line 6) +* subsym builtins, TIC54X: TIC54X-Macros. (line 16) +* subtitles for listings: Sbttl. (line 6) +* subtraction, permitted arguments: Infix Ops. (line 49) +* summary of options: Overview. (line 6) +* support: HPPA-Dependent. (line 6) +* supporting files, including: Include. (line 6) +* suppressing warnings: W. (line 11) +* sval: Z8000 Directives. (line 33) +* symbol attributes: Symbol Attributes. (line 6) +* symbol attributes, a.out: a.out Symbols. (line 6) +* symbol attributes, COFF: COFF Symbols. (line 6) +* symbol attributes, SOM: SOM Symbols. (line 6) +* symbol descriptor, COFF: Desc. (line 6) +* symbol modifiers <1>: AVR-Modifiers. (line 12) +* symbol modifiers <2>: LM32-Modifiers. (line 12) +* symbol modifiers <3>: M32C-Modifiers. (line 11) +* symbol modifiers: M68HC11-Modifiers. (line 12) +* symbol names: Symbol Names. (line 6) +* symbol names, $ in <1>: SH-Chars. (line 10) +* symbol names, $ in <2>: SH64-Chars. (line 10) +* symbol names, $ in <3>: D30V-Chars. (line 63) +* symbol names, $ in: D10V-Chars. (line 46) +* symbol names, local: Symbol Names. (line 22) +* symbol names, temporary: Symbol Names. (line 35) +* symbol storage class (COFF): Scl. (line 6) +* symbol type: Symbol Type. (line 6) +* symbol type, COFF: Type. (line 11) +* symbol type, ELF: Type. (line 22) +* symbol value: Symbol Value. (line 6) +* symbol value, setting: Set. (line 6) +* symbol values, assigning: Setting Symbols. (line 6) +* symbol versioning: Symver. (line 6) +* symbol, common: Comm. (line 6) +* symbol, making visible to linker: Global. (line 6) +* symbolic debuggers, information for: Stab. (line 6) +* symbols: Symbols. (line 6) +* Symbols in position-independent code, CRIS: CRIS-Pic. (line 6) +* symbols with uppercase, VAX/VMS: VAX-Opts. (line 42) +* symbols, assigning values to: Equ. (line 6) +* Symbols, built-in, CRIS: CRIS-Symbols. (line 6) +* Symbols, CRIS, built-in: CRIS-Symbols. (line 6) +* symbols, local common: Lcomm. (line 6) +* symver directive: Symver. (line 6) +* syntax compatibility, i386: i386-Syntax. (line 6) +* syntax compatibility, x86-64: i386-Syntax. (line 6) +* syntax, AVR: AVR-Modifiers. (line 6) +* syntax, Blackfin: Blackfin Syntax. (line 6) +* syntax, D10V: D10V-Syntax. (line 6) +* syntax, D30V: D30V-Syntax. (line 6) +* syntax, LM32: LM32-Modifiers. (line 6) +* syntax, M32C: M32C-Modifiers. (line 6) +* syntax, M680x0: M68K-Syntax. (line 8) +* syntax, M68HC11 <1>: M68HC11-Modifiers. (line 6) +* syntax, M68HC11: M68HC11-Syntax. (line 6) +* syntax, machine-independent: Syntax. (line 6) +* syntax, SPARC: Sparc-Aligned-Data. (line 21) +* syntax, Xtensa assembler: Xtensa Syntax. (line 6) +* sysproc directive, i960: Directives-i960. (line 37) +* tab (\t): Strings. (line 27) +* tab directive, TIC54X: TIC54X-Directives. (line 248) +* tag directive: Tag. (line 6) +* tag directive, TIC54X: TIC54X-Directives. (line 251) +* tdaoff pseudo-op, V850: V850 Opcodes. (line 81) +* temporary symbol names: Symbol Names. (line 35) +* text and data sections, joining: R. (line 6) +* text directive: Text. (line 6) +* text section: Ld Sections. (line 9) +* tfloat directive, i386: i386-Float. (line 14) +* tfloat directive, x86-64: i386-Float. (line 14) +* Thumb support: ARM-Dependent. (line 6) +* TIC54X builtin math functions: TIC54X-Builtins. (line 6) +* TIC54X machine directives: TIC54X-Directives. (line 6) +* TIC54X memory-mapped registers: TIC54X-MMRegs. (line 6) +* TIC54X options: TIC54X-Opts. (line 6) +* TIC54X subsym builtins: TIC54X-Macros. (line 16) +* TIC54X support: TIC54X-Dependent. (line 6) +* TIC54X-specific macros: TIC54X-Macros. (line 6) +* time, total for assembly: statistics. (line 6) +* title directive: Title. (line 6) +* tp register, V850: V850-Regs. (line 20) +* transform directive: Transform Directive. (line 6) +* trusted compiler: f. (line 6) +* turning preprocessing on and off: Preprocessing. (line 27) +* type directive (COFF version): Type. (line 11) +* type directive (ELF version): Type. (line 22) +* type of a symbol: Symbol Type. (line 6) +* ualong directive, SH: SH Directives. (line 6) +* uaword directive, SH: SH Directives. (line 6) +* ubyte directive, TIC54X: TIC54X-Directives. (line 36) +* uchar directive, TIC54X: TIC54X-Directives. (line 36) +* uhalf directive, TIC54X: TIC54X-Directives. (line 111) +* uint directive, TIC54X: TIC54X-Directives. (line 111) +* uleb128 directive: Uleb128. (line 6) +* ulong directive, TIC54X: TIC54X-Directives. (line 135) +* undefined section: Ld Sections. (line 36) +* union directive, TIC54X: TIC54X-Directives. (line 251) +* unsegm: Z8000 Directives. (line 14) +* usect directive, TIC54X: TIC54X-Directives. (line 263) +* ushort directive, TIC54X: TIC54X-Directives. (line 111) +* uword directive, TIC54X: TIC54X-Directives. (line 111) +* V850 command line options: V850 Options. (line 9) +* V850 floating point (IEEE): V850 Floating Point. (line 6) +* V850 line comment character: V850-Chars. (line 6) +* V850 machine directives: V850 Directives. (line 6) +* V850 opcodes: V850 Opcodes. (line 6) +* V850 options (none): V850 Options. (line 6) +* V850 register names: V850-Regs. (line 6) +* V850 support: V850-Dependent. (line 6) +* val directive: Val. (line 6) +* value attribute, COFF: Val. (line 6) +* value of a symbol: Symbol Value. (line 6) +* var directive, TIC54X: TIC54X-Directives. (line 273) +* VAX bitfields not supported: VAX-no. (line 6) +* VAX branch improvement: VAX-branch. (line 6) +* VAX command-line options ignored: VAX-Opts. (line 6) +* VAX displacement sizing character: VAX-operands. (line 12) +* VAX floating point: VAX-float. (line 6) +* VAX immediate character: VAX-operands. (line 6) +* VAX indirect character: VAX-operands. (line 9) +* VAX machine directives: VAX-directives. (line 6) +* VAX opcode mnemonics: VAX-opcodes. (line 6) +* VAX operand notation: VAX-operands. (line 6) +* VAX register names: VAX-operands. (line 17) +* VAX support: Vax-Dependent. (line 6) +* Vax-11 C compatibility: VAX-Opts. (line 42) +* VAX/VMS options: VAX-Opts. (line 42) +* version directive: Version. (line 6) +* version directive, TIC54X: TIC54X-Directives. (line 277) +* version of assembler: v. (line 6) +* versions of symbols: Symver. (line 6) +* visibility <1>: Internal. (line 6) +* visibility <2>: Protected. (line 6) +* visibility: Hidden. (line 6) +* VMS (VAX) options: VAX-Opts. (line 42) +* vtable_entry directive: VTableEntry. (line 6) +* vtable_inherit directive: VTableInherit. (line 6) +* warning directive: Warning. (line 6) +* warning for altered difference tables: K. (line 6) +* warning messages: Errors. (line 6) +* warnings, causing error: W. (line 16) +* warnings, M32R: M32R-Warnings. (line 6) +* warnings, suppressing: W. (line 11) +* warnings, switching on: W. (line 19) +* weak directive: Weak. (line 6) +* weakref directive: Weakref. (line 6) +* whitespace: Whitespace. (line 6) +* whitespace, removed by preprocessor: Preprocessing. (line 7) +* wide floating point directives, VAX: VAX-directives. (line 10) +* width directive, TIC54X: TIC54X-Directives. (line 127) +* Width of continuation lines of disassembly output: listing. (line 21) +* Width of first line disassembly output: listing. (line 16) +* Width of source line output: listing. (line 28) +* wmsg directive, TIC54X: TIC54X-Directives. (line 77) +* word directive: Word. (line 6) +* word directive, ARC: ARC Directives. (line 174) +* word directive, H8/300: H8/300 Directives. (line 6) +* word directive, i386: i386-Float. (line 21) +* word directive, SPARC: Sparc-Directives. (line 51) +* word directive, TIC54X: TIC54X-Directives. (line 111) +* word directive, x86-64: i386-Float. (line 21) +* writing patterns in memory: Fill. (line 6) +* wval: Z8000 Directives. (line 24) +* x86 machine directives: i386-Directives. (line 6) +* x86-64 arch directive: i386-Arch. (line 6) +* x86-64 att_syntax pseudo op: i386-Syntax. (line 6) +* x86-64 conversion instructions: i386-Mnemonics. (line 36) +* x86-64 floating point: i386-Float. (line 6) +* x86-64 immediate operands: i386-Syntax. (line 15) +* x86-64 instruction naming: i386-Mnemonics. (line 6) +* x86-64 intel_syntax pseudo op: i386-Syntax. (line 6) +* x86-64 jump optimization: i386-Jumps. (line 6) +* x86-64 jump, call, return: i386-Syntax. (line 38) +* x86-64 jump/call operands: i386-Syntax. (line 15) +* x86-64 memory references: i386-Memory. (line 6) +* x86-64 options: i386-Options. (line 6) +* x86-64 register operands: i386-Syntax. (line 15) +* x86-64 registers: i386-Regs. (line 6) +* x86-64 sections: i386-Syntax. (line 44) +* x86-64 size suffixes: i386-Syntax. (line 29) +* x86-64 source, destination operands: i386-Syntax. (line 22) +* x86-64 support: i386-Dependent. (line 6) +* x86-64 syntax compatibility: i386-Syntax. (line 6) +* xfloat directive, TIC54X: TIC54X-Directives. (line 64) +* xlong directive, TIC54X: TIC54X-Directives. (line 135) +* Xtensa architecture: Xtensa-Dependent. (line 6) +* Xtensa assembler syntax: Xtensa Syntax. (line 6) +* Xtensa directives: Xtensa Directives. (line 6) +* Xtensa opcode names: Xtensa Opcodes. (line 6) +* Xtensa register names: Xtensa Registers. (line 6) +* xword directive, SPARC: Sparc-Directives. (line 55) +* Z80 $: Z80-Chars. (line 8) +* Z80 ': Z80-Chars. (line 13) +* Z80 floating point: Z80 Floating Point. (line 6) +* Z80 line comment character: Z80-Chars. (line 6) +* Z80 options: Z80 Options. (line 6) +* Z80 registers: Z80-Regs. (line 6) +* Z80 support: Z80-Dependent. (line 6) +* Z80 Syntax: Z80 Options. (line 47) +* Z80, \: Z80-Chars. (line 11) +* Z80, case sensitivity: Z80-Case. (line 6) +* Z80-only directives: Z80 Directives. (line 9) +* Z800 addressing modes: Z8000-Addressing. (line 6) +* Z8000 directives: Z8000 Directives. (line 6) +* Z8000 line comment character: Z8000-Chars. (line 6) +* Z8000 line separator: Z8000-Chars. (line 8) +* Z8000 opcode summary: Z8000 Opcodes. (line 6) +* Z8000 options: Z8000 Options. (line 6) +* Z8000 registers: Z8000-Regs. (line 6) +* Z8000 support: Z8000-Dependent. (line 6) +* zdaoff pseudo-op, V850: V850 Opcodes. (line 99) +* zero register, V850: V850-Regs. (line 7) +* zero-terminated strings: Asciz. (line 6) + + + +Tag Table: +Node: Top770 +Node: Overview1756 +Node: Manual30673 +Node: GNU Assembler31617 +Node: Object Formats32788 +Node: Command Line33240 +Node: Input Files34327 +Node: Object36308 +Node: Errors37204 +Node: Invoking38399 +Node: a40354 +Node: alternate42265 +Node: D42437 +Node: f42670 +Node: I43178 +Node: K43722 +Node: L44026 +Node: listing44765 +Node: M46424 +Node: MD50825 +Node: o51251 +Node: R51706 +Node: statistics52736 +Node: traditional-format53143 +Node: v53616 +Node: W53891 +Node: Z54798 +Node: Syntax55320 +Node: Preprocessing55911 +Node: Whitespace57474 +Node: Comments57870 +Node: Symbol Intro60069 +Node: Statements60759 +Node: Constants62680 +Node: Characters63311 +Node: Strings63813 +Node: Chars65979 +Node: Numbers66733 +Node: Integers67273 +Node: Bignums67929 +Node: Flonums68285 +Node: Sections70032 +Node: Secs Background70410 +Node: Ld Sections75449 +Node: As Sections77833 +Node: Sub-Sections78743 +Node: bss81888 +Node: Symbols82838 +Node: Labels83486 +Node: Setting Symbols84217 +Node: Symbol Names84771 +Node: Dot89812 +Node: Symbol Attributes90259 +Node: Symbol Value90996 +Node: Symbol Type92041 +Node: a.out Symbols92429 +Node: Symbol Desc92691 +Node: Symbol Other92986 +Node: COFF Symbols93155 +Node: SOM Symbols93828 +Node: Expressions94270 +Node: Empty Exprs95019 +Node: Integer Exprs95366 +Node: Arguments95761 +Node: Operators96867 +Node: Prefix Ops97202 +Node: Infix Ops97530 +Node: Pseudo Ops99920 +Node: Abort105421 +Node: ABORT (COFF)105833 +Node: Align106041 +Node: Altmacro108323 +Node: Ascii109652 +Node: Asciz109961 +Node: Balign110206 +Node: Byte112069 +Node: CFI directives112317 +Node: Comm117944 +Ref: Comm-Footnote-1119545 +Node: Data119907 +Node: Def120224 +Node: Desc120456 +Node: Dim120956 +Node: Double121213 +Node: Eject121551 +Node: Else121726 +Node: Elseif122026 +Node: End122320 +Node: Endef122535 +Node: Endfunc122712 +Node: Endif122887 +Node: Equ123148 +Node: Equiv123662 +Node: Eqv124218 +Node: Err124582 +Node: 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+Node: GNU Free Documentation License684176 +Node: AS Index709345 + +End Tag Table diff --git a/uclibc-crosstools-gcc-4.4.2-1/usr/share/info/bfd.info b/uclibc-crosstools-gcc-4.4.2-1/usr/share/info/bfd.info new file mode 100644 index 0000000..576f2c5 --- /dev/null +++ b/uclibc-crosstools-gcc-4.4.2-1/usr/share/info/bfd.info @@ -0,0 +1,11288 @@ +This is bfd.info, produced by makeinfo version 4.8 from bfd.texinfo. + +START-INFO-DIR-ENTRY +* Bfd: (bfd). The Binary File Descriptor library. +END-INFO-DIR-ENTRY + + This file documents the BFD library. + + Copyright (C) 1991, 2000, 2001, 2003, 2006, 2007, 2008 Free Software +Foundation, Inc. + + Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation; with the +Invariant Sections being "GNU General Public License" and "Funding Free +Software", the Front-Cover texts being (a) (see below), and with the +Back-Cover Texts being (b) (see below). A copy of the license is +included in the section entitled "GNU Free Documentation License". + + (a) The FSF's Front-Cover Text is: + + A GNU Manual + + (b) The FSF's Back-Cover Text is: + + You have freedom to copy and modify this GNU Manual, like GNU +software. Copies published by the Free Software Foundation raise +funds for GNU development. + + +File: bfd.info, Node: Top, Next: Overview, Prev: (dir), Up: (dir) + + This file documents the binary file descriptor library libbfd. + +* Menu: + +* Overview:: Overview of BFD +* BFD front end:: BFD front end +* BFD back ends:: BFD back ends +* GNU Free Documentation License:: GNU Free Documentation License +* BFD Index:: BFD Index + + +File: bfd.info, Node: Overview, Next: BFD front end, Prev: Top, Up: Top + +1 Introduction +************** + +BFD is a package which allows applications to use the same routines to +operate on object files whatever the object file format. A new object +file format can be supported simply by creating a new BFD back end and +adding it to the library. + + BFD is split into two parts: the front end, and the back ends (one +for each object file format). + * The front end of BFD provides the interface to the user. It manages + memory and various canonical data structures. The front end also + decides which back end to use and when to call back end routines. + + * The back ends provide BFD its view of the real world. Each back + end provides a set of calls which the BFD front end can use to + maintain its canonical form. The back ends also may keep around + information for their own use, for greater efficiency. + +* Menu: + +* History:: History +* How It Works:: How It Works +* What BFD Version 2 Can Do:: What BFD Version 2 Can Do + + +File: bfd.info, Node: History, Next: How It Works, Prev: Overview, Up: Overview + +1.1 History +=========== + +One spur behind BFD was the desire, on the part of the GNU 960 team at +Intel Oregon, for interoperability of applications on their COFF and +b.out file formats. Cygnus was providing GNU support for the team, and +was contracted to provide the required functionality. + + The name came from a conversation David Wallace was having with +Richard Stallman about the library: RMS said that it would be quite +hard--David said "BFD". Stallman was right, but the name stuck. + + At the same time, Ready Systems wanted much the same thing, but for +different object file formats: IEEE-695, Oasys, Srecords, a.out and 68k +coff. + + BFD was first implemented by members of Cygnus Support; Steve +Chamberlain (`sac@cygnus.com'), John Gilmore (`gnu@cygnus.com'), K. +Richard Pixley (`rich@cygnus.com') and David Henkel-Wallace +(`gumby@cygnus.com'). + + +File: bfd.info, Node: How It Works, Next: What BFD Version 2 Can Do, Prev: History, Up: Overview + +1.2 How To Use BFD +================== + +To use the library, include `bfd.h' and link with `libbfd.a'. + + BFD provides a common interface to the parts of an object file for a +calling application. + + When an application successfully opens a target file (object, +archive, or whatever), a pointer to an internal structure is returned. +This pointer points to a structure called `bfd', described in `bfd.h'. +Our convention is to call this pointer a BFD, and instances of it +within code `abfd'. All operations on the target object file are +applied as methods to the BFD. The mapping is defined within `bfd.h' +in a set of macros, all beginning with `bfd_' to reduce namespace +pollution. + + For example, this sequence does what you would probably expect: +return the number of sections in an object file attached to a BFD +`abfd'. + + #include "bfd.h" + + unsigned int number_of_sections (abfd) + bfd *abfd; + { + return bfd_count_sections (abfd); + } + + The abstraction used within BFD is that an object file has: + + * a header, + + * a number of sections containing raw data (*note Sections::), + + * a set of relocations (*note Relocations::), and + + * some symbol information (*note Symbols::). + Also, BFDs opened for archives have the additional attribute of an +index and contain subordinate BFDs. This approach is fine for a.out and +coff, but loses efficiency when applied to formats such as S-records and +IEEE-695. + + +File: bfd.info, Node: What BFD Version 2 Can Do, Prev: How It Works, Up: Overview + +1.3 What BFD Version 2 Can Do +============================= + +When an object file is opened, BFD subroutines automatically determine +the format of the input object file. They then build a descriptor in +memory with pointers to routines that will be used to access elements of +the object file's data structures. + + As different information from the object files is required, BFD +reads from different sections of the file and processes them. For +example, a very common operation for the linker is processing symbol +tables. Each BFD back end provides a routine for converting between +the object file's representation of symbols and an internal canonical +format. When the linker asks for the symbol table of an object file, it +calls through a memory pointer to the routine from the relevant BFD +back end which reads and converts the table into a canonical form. The +linker then operates upon the canonical form. When the link is finished +and the linker writes the output file's symbol table, another BFD back +end routine is called to take the newly created symbol table and +convert it into the chosen output format. + +* Menu: + +* BFD information loss:: Information Loss +* Canonical format:: The BFD canonical object-file format + + +File: bfd.info, Node: BFD information loss, Next: Canonical format, Up: What BFD Version 2 Can Do + +1.3.1 Information Loss +---------------------- + +_Information can be lost during output._ The output formats supported +by BFD do not provide identical facilities, and information which can +be described in one form has nowhere to go in another format. One +example of this is alignment information in `b.out'. There is nowhere +in an `a.out' format file to store alignment information on the +contained data, so when a file is linked from `b.out' and an `a.out' +image is produced, alignment information will not propagate to the +output file. (The linker will still use the alignment information +internally, so the link is performed correctly). + + Another example is COFF section names. COFF files may contain an +unlimited number of sections, each one with a textual section name. If +the target of the link is a format which does not have many sections +(e.g., `a.out') or has sections without names (e.g., the Oasys format), +the link cannot be done simply. You can circumvent this problem by +describing the desired input-to-output section mapping with the linker +command language. + + _Information can be lost during canonicalization._ The BFD internal +canonical form of the external formats is not exhaustive; there are +structures in input formats for which there is no direct representation +internally. This means that the BFD back ends cannot maintain all +possible data richness through the transformation between external to +internal and back to external formats. + + This limitation is only a problem when an application reads one +format and writes another. Each BFD back end is responsible for +maintaining as much data as possible, and the internal BFD canonical +form has structures which are opaque to the BFD core, and exported only +to the back ends. When a file is read in one format, the canonical form +is generated for BFD and the application. At the same time, the back +end saves away any information which may otherwise be lost. If the data +is then written back in the same format, the back end routine will be +able to use the canonical form provided by the BFD core as well as the +information it prepared earlier. Since there is a great deal of +commonality between back ends, there is no information lost when +linking or copying big endian COFF to little endian COFF, or `a.out' to +`b.out'. When a mixture of formats is linked, the information is only +lost from the files whose format differs from the destination. + + +File: bfd.info, Node: Canonical format, Prev: BFD information loss, Up: What BFD Version 2 Can Do + +1.3.2 The BFD canonical object-file format +------------------------------------------ + +The greatest potential for loss of information occurs when there is the +least overlap between the information provided by the source format, +that stored by the canonical format, and that needed by the destination +format. A brief description of the canonical form may help you +understand which kinds of data you can count on preserving across +conversions. + +_files_ + Information stored on a per-file basis includes target machine + architecture, particular implementation format type, a demand + pageable bit, and a write protected bit. Information like Unix + magic numbers is not stored here--only the magic numbers' meaning, + so a `ZMAGIC' file would have both the demand pageable bit and the + write protected text bit set. The byte order of the target is + stored on a per-file basis, so that big- and little-endian object + files may be used with one another. + +_sections_ + Each section in the input file contains the name of the section, + the section's original address in the object file, size and + alignment information, various flags, and pointers into other BFD + data structures. + +_symbols_ + Each symbol contains a pointer to the information for the object + file which originally defined it, its name, its value, and various + flag bits. When a BFD back end reads in a symbol table, it + relocates all symbols to make them relative to the base of the + section where they were defined. Doing this ensures that each + symbol points to its containing section. Each symbol also has a + varying amount of hidden private data for the BFD back end. Since + the symbol points to the original file, the private data format + for that symbol is accessible. `ld' can operate on a collection + of symbols of wildly different formats without problems. + + Normal global and simple local symbols are maintained on output, + so an output file (no matter its format) will retain symbols + pointing to functions and to global, static, and common variables. + Some symbol information is not worth retaining; in `a.out', type + information is stored in the symbol table as long symbol names. + This information would be useless to most COFF debuggers; the + linker has command line switches to allow users to throw it away. + + There is one word of type information within the symbol, so if the + format supports symbol type information within symbols (for + example, COFF, IEEE, Oasys) and the type is simple enough to fit + within one word (nearly everything but aggregates), the + information will be preserved. + +_relocation level_ + Each canonical BFD relocation record contains a pointer to the + symbol to relocate to, the offset of the data to relocate, the + section the data is in, and a pointer to a relocation type + descriptor. Relocation is performed by passing messages through + the relocation type descriptor and the symbol pointer. Therefore, + relocations can be performed on output data using a relocation + method that is only available in one of the input formats. For + instance, Oasys provides a byte relocation format. A relocation + record requesting this relocation type would point indirectly to a + routine to perform this, so the relocation may be performed on a + byte being written to a 68k COFF file, even though 68k COFF has no + such relocation type. + +_line numbers_ + Object formats can contain, for debugging purposes, some form of + mapping between symbols, source line numbers, and addresses in the + output file. These addresses have to be relocated along with the + symbol information. Each symbol with an associated list of line + number records points to the first record of the list. The head + of a line number list consists of a pointer to the symbol, which + allows finding out the address of the function whose line number + is being described. The rest of the list is made up of pairs: + offsets into the section and line numbers. Any format which can + simply derive this information can pass it successfully between + formats (COFF, IEEE and Oasys). + + +File: bfd.info, Node: BFD front end, Next: BFD back ends, Prev: Overview, Up: Top + +2 BFD Front End +*************** + +2.1 `typedef bfd' +================= + +A BFD has type `bfd'; objects of this type are the cornerstone of any +application using BFD. Using BFD consists of making references though +the BFD and to data in the BFD. + + Here is the structure that defines the type `bfd'. It contains the +major data about the file and pointers to the rest of the data. + + + enum bfd_direction + { + no_direction = 0, + read_direction = 1, + write_direction = 2, + both_direction = 3 + }; + + struct bfd + { + /* A unique identifier of the BFD */ + unsigned int id; + + /* The filename the application opened the BFD with. */ + const char *filename; + + /* A pointer to the target jump table. */ + const struct bfd_target *xvec; + + /* The IOSTREAM, and corresponding IO vector that provide access + to the file backing the BFD. */ + void *iostream; + const struct bfd_iovec *iovec; + + /* The caching routines use these to maintain a + least-recently-used list of BFDs. */ + struct bfd *lru_prev, *lru_next; + + /* When a file is closed by the caching routines, BFD retains + state information on the file here... */ + ufile_ptr where; + + /* File modified time, if mtime_set is TRUE. */ + long mtime; + + /* Reserved for an unimplemented file locking extension. */ + int ifd; + + /* The format which belongs to the BFD. (object, core, etc.) */ + bfd_format format; + + /* The direction with which the BFD was opened. */ + enum bfd_direction direction; + + /* Format_specific flags. */ + flagword flags; + + /* Values that may appear in the flags field of a BFD. These also + appear in the object_flags field of the bfd_target structure, where + they indicate the set of flags used by that backend (not all flags + are meaningful for all object file formats) (FIXME: at the moment, + the object_flags values have mostly just been copied from backend + to another, and are not necessarily correct). */ + + #define BFD_NO_FLAGS 0x00 + + /* BFD contains relocation entries. */ + #define HAS_RELOC 0x01 + + /* BFD is directly executable. */ + #define EXEC_P 0x02 + + /* BFD has line number information (basically used for F_LNNO in a + COFF header). */ + #define HAS_LINENO 0x04 + + /* BFD has debugging information. */ + #define HAS_DEBUG 0x08 + + /* BFD has symbols. */ + #define HAS_SYMS 0x10 + + /* BFD has local symbols (basically used for F_LSYMS in a COFF + header). */ + #define HAS_LOCALS 0x20 + + /* BFD is a dynamic object. */ + #define DYNAMIC 0x40 + + /* Text section is write protected (if D_PAGED is not set, this is + like an a.out NMAGIC file) (the linker sets this by default, but + clears it for -r or -N). */ + #define WP_TEXT 0x80 + + /* BFD is dynamically paged (this is like an a.out ZMAGIC file) (the + linker sets this by default, but clears it for -r or -n or -N). */ + #define D_PAGED 0x100 + + /* BFD is relaxable (this means that bfd_relax_section may be able to + do something) (sometimes bfd_relax_section can do something even if + this is not set). */ + #define BFD_IS_RELAXABLE 0x200 + + /* This may be set before writing out a BFD to request using a + traditional format. For example, this is used to request that when + writing out an a.out object the symbols not be hashed to eliminate + duplicates. */ + #define BFD_TRADITIONAL_FORMAT 0x400 + + /* This flag indicates that the BFD contents are actually cached + in memory. If this is set, iostream points to a bfd_in_memory + struct. */ + #define BFD_IN_MEMORY 0x800 + + /* The sections in this BFD specify a memory page. */ + #define HAS_LOAD_PAGE 0x1000 + + /* This BFD has been created by the linker and doesn't correspond + to any input file. */ + #define BFD_LINKER_CREATED 0x2000 + + /* This may be set before writing out a BFD to request that it + be written using values for UIDs, GIDs, timestamps, etc. that + will be consistent from run to run. */ + #define BFD_DETERMINISTIC_OUTPUT 0x4000 + + /* Currently my_archive is tested before adding origin to + anything. I believe that this can become always an add of + origin, with origin set to 0 for non archive files. */ + ufile_ptr origin; + + /* The origin in the archive of the proxy entry. This will + normally be the same as origin, except for thin archives, + when it will contain the current offset of the proxy in the + thin archive rather than the offset of the bfd in its actual + container. */ + ufile_ptr proxy_origin; + + /* A hash table for section names. */ + struct bfd_hash_table section_htab; + + /* Pointer to linked list of sections. */ + struct bfd_section *sections; + + /* The last section on the section list. */ + struct bfd_section *section_last; + + /* The number of sections. */ + unsigned int section_count; + + /* Stuff only useful for object files: + The start address. */ + bfd_vma start_address; + + /* Used for input and output. */ + unsigned int symcount; + + /* Symbol table for output BFD (with symcount entries). + Also used by the linker to cache input BFD symbols. */ + struct bfd_symbol **outsymbols; + + /* Used for slurped dynamic symbol tables. */ + unsigned int dynsymcount; + + /* Pointer to structure which contains architecture information. */ + const struct bfd_arch_info *arch_info; + + /* Stuff only useful for archives. */ + void *arelt_data; + struct bfd *my_archive; /* The containing archive BFD. */ + struct bfd *archive_next; /* The next BFD in the archive. */ + struct bfd *archive_head; /* The first BFD in the archive. */ + struct bfd *nested_archives; /* List of nested archive in a flattened + thin archive. */ + + /* A chain of BFD structures involved in a link. */ + struct bfd *link_next; + + /* A field used by _bfd_generic_link_add_archive_symbols. This will + be used only for archive elements. */ + int archive_pass; + + /* Used by the back end to hold private data. */ + union + { + struct aout_data_struct *aout_data; + struct artdata *aout_ar_data; + struct _oasys_data *oasys_obj_data; + struct _oasys_ar_data *oasys_ar_data; + struct coff_tdata *coff_obj_data; + struct pe_tdata *pe_obj_data; + struct xcoff_tdata *xcoff_obj_data; + struct ecoff_tdata *ecoff_obj_data; + struct ieee_data_struct *ieee_data; + struct ieee_ar_data_struct *ieee_ar_data; + struct srec_data_struct *srec_data; + struct verilog_data_struct *verilog_data; + struct ihex_data_struct *ihex_data; + struct tekhex_data_struct *tekhex_data; + struct elf_obj_tdata *elf_obj_data; + struct nlm_obj_tdata *nlm_obj_data; + struct bout_data_struct *bout_data; + struct mmo_data_struct *mmo_data; + struct sun_core_struct *sun_core_data; + struct sco5_core_struct *sco5_core_data; + struct trad_core_struct *trad_core_data; + struct som_data_struct *som_data; + struct hpux_core_struct *hpux_core_data; + struct hppabsd_core_struct *hppabsd_core_data; + struct sgi_core_struct *sgi_core_data; + struct lynx_core_struct *lynx_core_data; + struct osf_core_struct *osf_core_data; + struct cisco_core_struct *cisco_core_data; + struct versados_data_struct *versados_data; + struct netbsd_core_struct *netbsd_core_data; + struct mach_o_data_struct *mach_o_data; + struct mach_o_fat_data_struct *mach_o_fat_data; + struct plugin_data_struct *plugin_data; + struct bfd_pef_data_struct *pef_data; + struct bfd_pef_xlib_data_struct *pef_xlib_data; + struct bfd_sym_data_struct *sym_data; + void *any; + } + tdata; + + /* Used by the application to hold private data. */ + void *usrdata; + + /* Where all the allocated stuff under this BFD goes. This is a + struct objalloc *, but we use void * to avoid requiring the inclusion + of objalloc.h. */ + void *memory; + + /* Is the file descriptor being cached? That is, can it be closed as + needed, and re-opened when accessed later? */ + unsigned int cacheable : 1; + + /* Marks whether there was a default target specified when the + BFD was opened. This is used to select which matching algorithm + to use to choose the back end. */ + unsigned int target_defaulted : 1; + + /* ... and here: (``once'' means at least once). */ + unsigned int opened_once : 1; + + /* Set if we have a locally maintained mtime value, rather than + getting it from the file each time. */ + unsigned int mtime_set : 1; + + /* Flag set if symbols from this BFD should not be exported. */ + unsigned int no_export : 1; + + /* Remember when output has begun, to stop strange things + from happening. */ + unsigned int output_has_begun : 1; + + /* Have archive map. */ + unsigned int has_armap : 1; + + /* Set if this is a thin archive. */ + unsigned int is_thin_archive : 1; + }; + +2.2 Error reporting +=================== + +Most BFD functions return nonzero on success (check their individual +documentation for precise semantics). On an error, they call +`bfd_set_error' to set an error condition that callers can check by +calling `bfd_get_error'. If that returns `bfd_error_system_call', then +check `errno'. + + The easiest way to report a BFD error to the user is to use +`bfd_perror'. + +2.2.1 Type `bfd_error_type' +--------------------------- + +The values returned by `bfd_get_error' are defined by the enumerated +type `bfd_error_type'. + + + typedef enum bfd_error + { + bfd_error_no_error = 0, + bfd_error_system_call, + bfd_error_invalid_target, + bfd_error_wrong_format, + bfd_error_wrong_object_format, + bfd_error_invalid_operation, + bfd_error_no_memory, + bfd_error_no_symbols, + bfd_error_no_armap, + bfd_error_no_more_archived_files, + bfd_error_malformed_archive, + bfd_error_file_not_recognized, + bfd_error_file_ambiguously_recognized, + bfd_error_no_contents, + bfd_error_nonrepresentable_section, + bfd_error_no_debug_section, + bfd_error_bad_value, + bfd_error_file_truncated, + bfd_error_file_too_big, + bfd_error_on_input, + bfd_error_invalid_error_code + } + bfd_error_type; + +2.2.1.1 `bfd_get_error' +....................... + +*Synopsis* + bfd_error_type bfd_get_error (void); + *Description* +Return the current BFD error condition. + +2.2.1.2 `bfd_set_error' +....................... + +*Synopsis* + void bfd_set_error (bfd_error_type error_tag, ...); + *Description* +Set the BFD error condition to be ERROR_TAG. If ERROR_TAG is +bfd_error_on_input, then this function takes two more parameters, the +input bfd where the error occurred, and the bfd_error_type error. + +2.2.1.3 `bfd_errmsg' +.................... + +*Synopsis* + const char *bfd_errmsg (bfd_error_type error_tag); + *Description* +Return a string describing the error ERROR_TAG, or the system error if +ERROR_TAG is `bfd_error_system_call'. + +2.2.1.4 `bfd_perror' +.................... + +*Synopsis* + void bfd_perror (const char *message); + *Description* +Print to the standard error stream a string describing the last BFD +error that occurred, or the last system error if the last BFD error was +a system call failure. If MESSAGE is non-NULL and non-empty, the error +string printed is preceded by MESSAGE, a colon, and a space. It is +followed by a newline. + +2.2.2 BFD error handler +----------------------- + +Some BFD functions want to print messages describing the problem. They +call a BFD error handler function. This function may be overridden by +the program. + + The BFD error handler acts like printf. + + + typedef void (*bfd_error_handler_type) (const char *, ...); + +2.2.2.1 `bfd_set_error_handler' +............................... + +*Synopsis* + bfd_error_handler_type bfd_set_error_handler (bfd_error_handler_type); + *Description* +Set the BFD error handler function. Returns the previous function. + +2.2.2.2 `bfd_set_error_program_name' +.................................... + +*Synopsis* + void bfd_set_error_program_name (const char *); + *Description* +Set the program name to use when printing a BFD error. This is printed +before the error message followed by a colon and space. The string +must not be changed after it is passed to this function. + +2.2.2.3 `bfd_get_error_handler' +............................... + +*Synopsis* + bfd_error_handler_type bfd_get_error_handler (void); + *Description* +Return the BFD error handler function. + +2.3 Miscellaneous +================= + +2.3.1 Miscellaneous functions +----------------------------- + +2.3.1.1 `bfd_get_reloc_upper_bound' +................................... + +*Synopsis* + long bfd_get_reloc_upper_bound (bfd *abfd, asection *sect); + *Description* +Return the number of bytes required to store the relocation information +associated with section SECT attached to bfd ABFD. If an error occurs, +return -1. + +2.3.1.2 `bfd_canonicalize_reloc' +................................ + +*Synopsis* + long bfd_canonicalize_reloc + (bfd *abfd, asection *sec, arelent **loc, asymbol **syms); + *Description* +Call the back end associated with the open BFD ABFD and translate the +external form of the relocation information attached to SEC into the +internal canonical form. Place the table into memory at LOC, which has +been preallocated, usually by a call to `bfd_get_reloc_upper_bound'. +Returns the number of relocs, or -1 on error. + + The SYMS table is also needed for horrible internal magic reasons. + +2.3.1.3 `bfd_set_reloc' +....................... + +*Synopsis* + void bfd_set_reloc + (bfd *abfd, asection *sec, arelent **rel, unsigned int count); + *Description* +Set the relocation pointer and count within section SEC to the values +REL and COUNT. The argument ABFD is ignored. + +2.3.1.4 `bfd_set_file_flags' +............................ + +*Synopsis* + bfd_boolean bfd_set_file_flags (bfd *abfd, flagword flags); + *Description* +Set the flag word in the BFD ABFD to the value FLAGS. + + Possible errors are: + * `bfd_error_wrong_format' - The target bfd was not of object format. + + * `bfd_error_invalid_operation' - The target bfd was open for + reading. + + * `bfd_error_invalid_operation' - The flag word contained a bit + which was not applicable to the type of file. E.g., an attempt + was made to set the `D_PAGED' bit on a BFD format which does not + support demand paging. + +2.3.1.5 `bfd_get_arch_size' +........................... + +*Synopsis* + int bfd_get_arch_size (bfd *abfd); + *Description* +Returns the architecture address size, in bits, as determined by the +object file's format. For ELF, this information is included in the +header. + + *Returns* +Returns the arch size in bits if known, `-1' otherwise. + +2.3.1.6 `bfd_get_sign_extend_vma' +................................. + +*Synopsis* + int bfd_get_sign_extend_vma (bfd *abfd); + *Description* +Indicates if the target architecture "naturally" sign extends an +address. Some architectures implicitly sign extend address values when +they are converted to types larger than the size of an address. For +instance, bfd_get_start_address() will return an address sign extended +to fill a bfd_vma when this is the case. + + *Returns* +Returns `1' if the target architecture is known to sign extend +addresses, `0' if the target architecture is known to not sign extend +addresses, and `-1' otherwise. + +2.3.1.7 `bfd_set_start_address' +............................... + +*Synopsis* + bfd_boolean bfd_set_start_address (bfd *abfd, bfd_vma vma); + *Description* +Make VMA the entry point of output BFD ABFD. + + *Returns* +Returns `TRUE' on success, `FALSE' otherwise. + +2.3.1.8 `bfd_get_gp_size' +......................... + +*Synopsis* + unsigned int bfd_get_gp_size (bfd *abfd); + *Description* +Return the maximum size of objects to be optimized using the GP +register under MIPS ECOFF. This is typically set by the `-G' argument +to the compiler, assembler or linker. + +2.3.1.9 `bfd_set_gp_size' +......................... + +*Synopsis* + void bfd_set_gp_size (bfd *abfd, unsigned int i); + *Description* +Set the maximum size of objects to be optimized using the GP register +under ECOFF or MIPS ELF. This is typically set by the `-G' argument to +the compiler, assembler or linker. + +2.3.1.10 `bfd_scan_vma' +....................... + +*Synopsis* + bfd_vma bfd_scan_vma (const char *string, const char **end, int base); + *Description* +Convert, like `strtoul', a numerical expression STRING into a `bfd_vma' +integer, and return that integer. (Though without as many bells and +whistles as `strtoul'.) The expression is assumed to be unsigned +(i.e., positive). If given a BASE, it is used as the base for +conversion. A base of 0 causes the function to interpret the string in +hex if a leading "0x" or "0X" is found, otherwise in octal if a leading +zero is found, otherwise in decimal. + + If the value would overflow, the maximum `bfd_vma' value is returned. + +2.3.1.11 `bfd_copy_private_header_data' +....................................... + +*Synopsis* + bfd_boolean bfd_copy_private_header_data (bfd *ibfd, bfd *obfd); + *Description* +Copy private BFD header information from the BFD IBFD to the the BFD +OBFD. This copies information that may require sections to exist, but +does not require symbol tables. Return `true' on success, `false' on +error. Possible error returns are: + + * `bfd_error_no_memory' - Not enough memory exists to create private + data for OBFD. + + #define bfd_copy_private_header_data(ibfd, obfd) \ + BFD_SEND (obfd, _bfd_copy_private_header_data, \ + (ibfd, obfd)) + +2.3.1.12 `bfd_copy_private_bfd_data' +.................................... + +*Synopsis* + bfd_boolean bfd_copy_private_bfd_data (bfd *ibfd, bfd *obfd); + *Description* +Copy private BFD information from the BFD IBFD to the the BFD OBFD. +Return `TRUE' on success, `FALSE' on error. Possible error returns are: + + * `bfd_error_no_memory' - Not enough memory exists to create private + data for OBFD. + + #define bfd_copy_private_bfd_data(ibfd, obfd) \ + BFD_SEND (obfd, _bfd_copy_private_bfd_data, \ + (ibfd, obfd)) + +2.3.1.13 `bfd_merge_private_bfd_data' +..................................... + +*Synopsis* + bfd_boolean bfd_merge_private_bfd_data (bfd *ibfd, bfd *obfd); + *Description* +Merge private BFD information from the BFD IBFD to the the output file +BFD OBFD when linking. Return `TRUE' on success, `FALSE' on error. +Possible error returns are: + + * `bfd_error_no_memory' - Not enough memory exists to create private + data for OBFD. + + #define bfd_merge_private_bfd_data(ibfd, obfd) \ + BFD_SEND (obfd, _bfd_merge_private_bfd_data, \ + (ibfd, obfd)) + +2.3.1.14 `bfd_set_private_flags' +................................ + +*Synopsis* + bfd_boolean bfd_set_private_flags (bfd *abfd, flagword flags); + *Description* +Set private BFD flag information in the BFD ABFD. Return `TRUE' on +success, `FALSE' on error. Possible error returns are: + + * `bfd_error_no_memory' - Not enough memory exists to create private + data for OBFD. + + #define bfd_set_private_flags(abfd, flags) \ + BFD_SEND (abfd, _bfd_set_private_flags, (abfd, flags)) + +2.3.1.15 `Other functions' +.......................... + +*Description* +The following functions exist but have not yet been documented. + #define bfd_sizeof_headers(abfd, info) \ + BFD_SEND (abfd, _bfd_sizeof_headers, (abfd, info)) + + #define bfd_find_nearest_line(abfd, sec, syms, off, file, func, line) \ + BFD_SEND (abfd, _bfd_find_nearest_line, \ + (abfd, sec, syms, off, file, func, line)) + + #define bfd_find_line(abfd, syms, sym, file, line) \ + BFD_SEND (abfd, _bfd_find_line, \ + (abfd, syms, sym, file, line)) + + #define bfd_find_inliner_info(abfd, file, func, line) \ + BFD_SEND (abfd, _bfd_find_inliner_info, \ + (abfd, file, func, line)) + + #define bfd_debug_info_start(abfd) \ + BFD_SEND (abfd, _bfd_debug_info_start, (abfd)) + + #define bfd_debug_info_end(abfd) \ + BFD_SEND (abfd, _bfd_debug_info_end, (abfd)) + + #define bfd_debug_info_accumulate(abfd, section) \ + BFD_SEND (abfd, _bfd_debug_info_accumulate, (abfd, section)) + + #define bfd_stat_arch_elt(abfd, stat) \ + BFD_SEND (abfd, _bfd_stat_arch_elt,(abfd, stat)) + + #define bfd_update_armap_timestamp(abfd) \ + BFD_SEND (abfd, _bfd_update_armap_timestamp, (abfd)) + + #define bfd_set_arch_mach(abfd, arch, mach)\ + BFD_SEND ( abfd, _bfd_set_arch_mach, (abfd, arch, mach)) + + #define bfd_relax_section(abfd, section, link_info, again) \ + BFD_SEND (abfd, _bfd_relax_section, (abfd, section, link_info, again)) + + #define bfd_gc_sections(abfd, link_info) \ + BFD_SEND (abfd, _bfd_gc_sections, (abfd, link_info)) + + #define bfd_merge_sections(abfd, link_info) \ + BFD_SEND (abfd, _bfd_merge_sections, (abfd, link_info)) + + #define bfd_is_group_section(abfd, sec) \ + BFD_SEND (abfd, _bfd_is_group_section, (abfd, sec)) + + #define bfd_discard_group(abfd, sec) \ + BFD_SEND (abfd, _bfd_discard_group, (abfd, sec)) + + #define bfd_link_hash_table_create(abfd) \ + BFD_SEND (abfd, _bfd_link_hash_table_create, (abfd)) + + #define bfd_link_hash_table_free(abfd, hash) \ + BFD_SEND (abfd, _bfd_link_hash_table_free, (hash)) + + #define bfd_link_add_symbols(abfd, info) \ + BFD_SEND (abfd, _bfd_link_add_symbols, (abfd, info)) + + #define bfd_link_just_syms(abfd, sec, info) \ + BFD_SEND (abfd, _bfd_link_just_syms, (sec, info)) + + #define bfd_final_link(abfd, info) \ + BFD_SEND (abfd, _bfd_final_link, (abfd, info)) + + #define bfd_free_cached_info(abfd) \ + BFD_SEND (abfd, _bfd_free_cached_info, (abfd)) + + #define bfd_get_dynamic_symtab_upper_bound(abfd) \ + BFD_SEND (abfd, _bfd_get_dynamic_symtab_upper_bound, (abfd)) + + #define bfd_print_private_bfd_data(abfd, file)\ + BFD_SEND (abfd, _bfd_print_private_bfd_data, (abfd, file)) + + #define bfd_canonicalize_dynamic_symtab(abfd, asymbols) \ + BFD_SEND (abfd, _bfd_canonicalize_dynamic_symtab, (abfd, asymbols)) + + #define bfd_get_synthetic_symtab(abfd, count, syms, dyncount, dynsyms, ret) \ + BFD_SEND (abfd, _bfd_get_synthetic_symtab, (abfd, count, syms, \ + dyncount, dynsyms, ret)) + + #define bfd_get_dynamic_reloc_upper_bound(abfd) \ + BFD_SEND (abfd, _bfd_get_dynamic_reloc_upper_bound, (abfd)) + + #define bfd_canonicalize_dynamic_reloc(abfd, arels, asyms) \ + BFD_SEND (abfd, _bfd_canonicalize_dynamic_reloc, (abfd, arels, asyms)) + + extern bfd_byte *bfd_get_relocated_section_contents + (bfd *, struct bfd_link_info *, struct bfd_link_order *, bfd_byte *, + bfd_boolean, asymbol **); + +2.3.1.16 `bfd_alt_mach_code' +............................ + +*Synopsis* + bfd_boolean bfd_alt_mach_code (bfd *abfd, int alternative); + *Description* +When more than one machine code number is available for the same +machine type, this function can be used to switch between the preferred +one (alternative == 0) and any others. Currently, only ELF supports +this feature, with up to two alternate machine codes. + + struct bfd_preserve + { + void *marker; + void *tdata; + flagword flags; + const struct bfd_arch_info *arch_info; + struct bfd_section *sections; + struct bfd_section *section_last; + unsigned int section_count; + struct bfd_hash_table section_htab; + }; + +2.3.1.17 `bfd_preserve_save' +............................ + +*Synopsis* + bfd_boolean bfd_preserve_save (bfd *, struct bfd_preserve *); + *Description* +When testing an object for compatibility with a particular target +back-end, the back-end object_p function needs to set up certain fields +in the bfd on successfully recognizing the object. This typically +happens in a piecemeal fashion, with failures possible at many points. +On failure, the bfd is supposed to be restored to its initial state, +which is virtually impossible. However, restoring a subset of the bfd +state works in practice. This function stores the subset and +reinitializes the bfd. + +2.3.1.18 `bfd_preserve_restore' +............................... + +*Synopsis* + void bfd_preserve_restore (bfd *, struct bfd_preserve *); + *Description* +This function restores bfd state saved by bfd_preserve_save. If MARKER +is non-NULL in struct bfd_preserve then that block and all subsequently +bfd_alloc'd memory is freed. + +2.3.1.19 `bfd_preserve_finish' +.............................. + +*Synopsis* + void bfd_preserve_finish (bfd *, struct bfd_preserve *); + *Description* +This function should be called when the bfd state saved by +bfd_preserve_save is no longer needed. ie. when the back-end object_p +function returns with success. + +2.3.1.20 `bfd_emul_get_maxpagesize' +................................... + +*Synopsis* + bfd_vma bfd_emul_get_maxpagesize (const char *); + *Description* +Returns the maximum page size, in bytes, as determined by emulation. + + *Returns* +Returns the maximum page size in bytes for ELF, 0 otherwise. + +2.3.1.21 `bfd_emul_set_maxpagesize' +................................... + +*Synopsis* + void bfd_emul_set_maxpagesize (const char *, bfd_vma); + *Description* +For ELF, set the maximum page size for the emulation. It is a no-op +for other formats. + +2.3.1.22 `bfd_emul_get_commonpagesize' +...................................... + +*Synopsis* + bfd_vma bfd_emul_get_commonpagesize (const char *); + *Description* +Returns the common page size, in bytes, as determined by emulation. + + *Returns* +Returns the common page size in bytes for ELF, 0 otherwise. + +2.3.1.23 `bfd_emul_set_commonpagesize' +...................................... + +*Synopsis* + void bfd_emul_set_commonpagesize (const char *, bfd_vma); + *Description* +For ELF, set the common page size for the emulation. It is a no-op for +other formats. + +2.3.1.24 `bfd_demangle' +....................... + +*Synopsis* + char *bfd_demangle (bfd *, const char *, int); + *Description* +Wrapper around cplus_demangle. Strips leading underscores and other +such chars that would otherwise confuse the demangler. If passed a g++ +v3 ABI mangled name, returns a buffer allocated with malloc holding the +demangled name. Returns NULL otherwise and on memory alloc failure. + +2.3.1.25 `struct bfd_iovec' +........................... + +*Description* +The `struct bfd_iovec' contains the internal file I/O class. Each +`BFD' has an instance of this class and all file I/O is routed through +it (it is assumed that the instance implements all methods listed +below). + struct bfd_iovec + { + /* To avoid problems with macros, a "b" rather than "f" + prefix is prepended to each method name. */ + /* Attempt to read/write NBYTES on ABFD's IOSTREAM storing/fetching + bytes starting at PTR. Return the number of bytes actually + transfered (a read past end-of-file returns less than NBYTES), + or -1 (setting `bfd_error') if an error occurs. */ + file_ptr (*bread) (struct bfd *abfd, void *ptr, file_ptr nbytes); + file_ptr (*bwrite) (struct bfd *abfd, const void *ptr, + file_ptr nbytes); + /* Return the current IOSTREAM file offset, or -1 (setting `bfd_error' + if an error occurs. */ + file_ptr (*btell) (struct bfd *abfd); + /* For the following, on successful completion a value of 0 is returned. + Otherwise, a value of -1 is returned (and `bfd_error' is set). */ + int (*bseek) (struct bfd *abfd, file_ptr offset, int whence); + int (*bclose) (struct bfd *abfd); + int (*bflush) (struct bfd *abfd); + int (*bstat) (struct bfd *abfd, struct stat *sb); + /* Just like mmap: (void*)-1 on failure, mmapped address on success. */ + void *(*bmmap) (struct bfd *abfd, void *addr, bfd_size_type len, + int prot, int flags, file_ptr offset); + }; + +2.3.1.26 `bfd_get_mtime' +........................ + +*Synopsis* + long bfd_get_mtime (bfd *abfd); + *Description* +Return the file modification time (as read from the file system, or +from the archive header for archive members). + +2.3.1.27 `bfd_get_size' +....................... + +*Synopsis* + file_ptr bfd_get_size (bfd *abfd); + *Description* +Return the file size (as read from file system) for the file associated +with BFD ABFD. + + The initial motivation for, and use of, this routine is not so we +can get the exact size of the object the BFD applies to, since that +might not be generally possible (archive members for example). It +would be ideal if someone could eventually modify it so that such +results were guaranteed. + + Instead, we want to ask questions like "is this NNN byte sized +object I'm about to try read from file offset YYY reasonable?" As as +example of where we might do this, some object formats use string +tables for which the first `sizeof (long)' bytes of the table contain +the size of the table itself, including the size bytes. If an +application tries to read what it thinks is one of these string tables, +without some way to validate the size, and for some reason the size is +wrong (byte swapping error, wrong location for the string table, etc.), +the only clue is likely to be a read error when it tries to read the +table, or a "virtual memory exhausted" error when it tries to allocate +15 bazillon bytes of space for the 15 bazillon byte table it is about +to read. This function at least allows us to answer the question, "is +the size reasonable?". + +2.3.1.28 `bfd_mmap' +................... + +*Synopsis* + void *bfd_mmap (bfd *abfd, void *addr, bfd_size_type len, + int prot, int flags, file_ptr offset); + *Description* +Return mmap()ed region of the file, if possible and implemented. + +* Menu: + +* Memory Usage:: +* Initialization:: +* Sections:: +* Symbols:: +* Archives:: +* Formats:: +* Relocations:: +* Core Files:: +* Targets:: +* Architectures:: +* Opening and Closing:: +* Internal:: +* File Caching:: +* Linker Functions:: +* Hash Tables:: + + +File: bfd.info, Node: Memory Usage, Next: Initialization, Prev: BFD front end, Up: BFD front end + +2.4 Memory Usage +================ + +BFD keeps all of its internal structures in obstacks. There is one +obstack per open BFD file, into which the current state is stored. When +a BFD is closed, the obstack is deleted, and so everything which has +been allocated by BFD for the closing file is thrown away. + + BFD does not free anything created by an application, but pointers +into `bfd' structures become invalid on a `bfd_close'; for example, +after a `bfd_close' the vector passed to `bfd_canonicalize_symtab' is +still around, since it has been allocated by the application, but the +data that it pointed to are lost. + + The general rule is to not close a BFD until all operations dependent +upon data from the BFD have been completed, or all the data from within +the file has been copied. To help with the management of memory, there +is a function (`bfd_alloc_size') which returns the number of bytes in +obstacks associated with the supplied BFD. This could be used to select +the greediest open BFD, close it to reclaim the memory, perform some +operation and reopen the BFD again, to get a fresh copy of the data +structures. + + +File: bfd.info, Node: Initialization, Next: Sections, Prev: Memory Usage, Up: BFD front end + +2.5 Initialization +================== + +2.5.1 Initialization functions +------------------------------ + +These are the functions that handle initializing a BFD. + +2.5.1.1 `bfd_init' +.................. + +*Synopsis* + void bfd_init (void); + *Description* +This routine must be called before any other BFD function to initialize +magical internal data structures. + + +File: bfd.info, Node: Sections, Next: Symbols, Prev: Initialization, Up: BFD front end + +2.6 Sections +============ + +The raw data contained within a BFD is maintained through the section +abstraction. A single BFD may have any number of sections. It keeps +hold of them by pointing to the first; each one points to the next in +the list. + + Sections are supported in BFD in `section.c'. + +* Menu: + +* Section Input:: +* Section Output:: +* typedef asection:: +* section prototypes:: + + +File: bfd.info, Node: Section Input, Next: Section Output, Prev: Sections, Up: Sections + +2.6.1 Section input +------------------- + +When a BFD is opened for reading, the section structures are created +and attached to the BFD. + + Each section has a name which describes the section in the outside +world--for example, `a.out' would contain at least three sections, +called `.text', `.data' and `.bss'. + + Names need not be unique; for example a COFF file may have several +sections named `.data'. + + Sometimes a BFD will contain more than the "natural" number of +sections. A back end may attach other sections containing constructor +data, or an application may add a section (using `bfd_make_section') to +the sections attached to an already open BFD. For example, the linker +creates an extra section `COMMON' for each input file's BFD to hold +information about common storage. + + The raw data is not necessarily read in when the section descriptor +is created. Some targets may leave the data in place until a +`bfd_get_section_contents' call is made. Other back ends may read in +all the data at once. For example, an S-record file has to be read +once to determine the size of the data. An IEEE-695 file doesn't +contain raw data in sections, but data and relocation expressions +intermixed, so the data area has to be parsed to get out the data and +relocations. + + +File: bfd.info, Node: Section Output, Next: typedef asection, Prev: Section Input, Up: Sections + +2.6.2 Section output +-------------------- + +To write a new object style BFD, the various sections to be written +have to be created. They are attached to the BFD in the same way as +input sections; data is written to the sections using +`bfd_set_section_contents'. + + Any program that creates or combines sections (e.g., the assembler +and linker) must use the `asection' fields `output_section' and +`output_offset' to indicate the file sections to which each section +must be written. (If the section is being created from scratch, +`output_section' should probably point to the section itself and +`output_offset' should probably be zero.) + + The data to be written comes from input sections attached (via +`output_section' pointers) to the output sections. The output section +structure can be considered a filter for the input section: the output +section determines the vma of the output data and the name, but the +input section determines the offset into the output section of the data +to be written. + + E.g., to create a section "O", starting at 0x100, 0x123 long, +containing two subsections, "A" at offset 0x0 (i.e., at vma 0x100) and +"B" at offset 0x20 (i.e., at vma 0x120) the `asection' structures would +look like: + + section name "A" + output_offset 0x00 + size 0x20 + output_section -----------> section name "O" + | vma 0x100 + section name "B" | size 0x123 + output_offset 0x20 | + size 0x103 | + output_section --------| + +2.6.3 Link orders +----------------- + +The data within a section is stored in a "link_order". These are much +like the fixups in `gas'. The link_order abstraction allows a section +to grow and shrink within itself. + + A link_order knows how big it is, and which is the next link_order +and where the raw data for it is; it also points to a list of +relocations which apply to it. + + The link_order is used by the linker to perform relaxing on final +code. The compiler creates code which is as big as necessary to make +it work without relaxing, and the user can select whether to relax. +Sometimes relaxing takes a lot of time. The linker runs around the +relocations to see if any are attached to data which can be shrunk, if +so it does it on a link_order by link_order basis. + + +File: bfd.info, Node: typedef asection, Next: section prototypes, Prev: Section Output, Up: Sections + +2.6.4 typedef asection +---------------------- + +Here is the section structure: + + + typedef struct bfd_section + { + /* The name of the section; the name isn't a copy, the pointer is + the same as that passed to bfd_make_section. */ + const char *name; + + /* A unique sequence number. */ + int id; + + /* Which section in the bfd; 0..n-1 as sections are created in a bfd. */ + int index; + + /* The next section in the list belonging to the BFD, or NULL. */ + struct bfd_section *next; + + /* The previous section in the list belonging to the BFD, or NULL. */ + struct bfd_section *prev; + + /* The field flags contains attributes of the section. Some + flags are read in from the object file, and some are + synthesized from other information. */ + flagword flags; + + #define SEC_NO_FLAGS 0x000 + + /* Tells the OS to allocate space for this section when loading. + This is clear for a section containing debug information only. */ + #define SEC_ALLOC 0x001 + + /* Tells the OS to load the section from the file when loading. + This is clear for a .bss section. */ + #define SEC_LOAD 0x002 + + /* The section contains data still to be relocated, so there is + some relocation information too. */ + #define SEC_RELOC 0x004 + + /* A signal to the OS that the section contains read only data. */ + #define SEC_READONLY 0x008 + + /* The section contains code only. */ + #define SEC_CODE 0x010 + + /* The section contains data only. */ + #define SEC_DATA 0x020 + + /* The section will reside in ROM. */ + #define SEC_ROM 0x040 + + /* The section contains constructor information. This section + type is used by the linker to create lists of constructors and + destructors used by `g++'. When a back end sees a symbol + which should be used in a constructor list, it creates a new + section for the type of name (e.g., `__CTOR_LIST__'), attaches + the symbol to it, and builds a relocation. To build the lists + of constructors, all the linker has to do is catenate all the + sections called `__CTOR_LIST__' and relocate the data + contained within - exactly the operations it would peform on + standard data. */ + #define SEC_CONSTRUCTOR 0x080 + + /* The section has contents - a data section could be + `SEC_ALLOC' | `SEC_HAS_CONTENTS'; a debug section could be + `SEC_HAS_CONTENTS' */ + #define SEC_HAS_CONTENTS 0x100 + + /* An instruction to the linker to not output the section + even if it has information which would normally be written. */ + #define SEC_NEVER_LOAD 0x200 + + /* The section contains thread local data. */ + #define SEC_THREAD_LOCAL 0x400 + + /* The section has GOT references. This flag is only for the + linker, and is currently only used by the elf32-hppa back end. + It will be set if global offset table references were detected + in this section, which indicate to the linker that the section + contains PIC code, and must be handled specially when doing a + static link. */ + #define SEC_HAS_GOT_REF 0x800 + + /* The section contains common symbols (symbols may be defined + multiple times, the value of a symbol is the amount of + space it requires, and the largest symbol value is the one + used). Most targets have exactly one of these (which we + translate to bfd_com_section_ptr), but ECOFF has two. */ + #define SEC_IS_COMMON 0x1000 + + /* The section contains only debugging information. For + example, this is set for ELF .debug and .stab sections. + strip tests this flag to see if a section can be + discarded. */ + #define SEC_DEBUGGING 0x2000 + + /* The contents of this section are held in memory pointed to + by the contents field. This is checked by bfd_get_section_contents, + and the data is retrieved from memory if appropriate. */ + #define SEC_IN_MEMORY 0x4000 + + /* The contents of this section are to be excluded by the + linker for executable and shared objects unless those + objects are to be further relocated. */ + #define SEC_EXCLUDE 0x8000 + + /* The contents of this section are to be sorted based on the sum of + the symbol and addend values specified by the associated relocation + entries. Entries without associated relocation entries will be + appended to the end of the section in an unspecified order. */ + #define SEC_SORT_ENTRIES 0x10000 + + /* When linking, duplicate sections of the same name should be + discarded, rather than being combined into a single section as + is usually done. This is similar to how common symbols are + handled. See SEC_LINK_DUPLICATES below. */ + #define SEC_LINK_ONCE 0x20000 + + /* If SEC_LINK_ONCE is set, this bitfield describes how the linker + should handle duplicate sections. */ + #define SEC_LINK_DUPLICATES 0xc0000 + + /* This value for SEC_LINK_DUPLICATES means that duplicate + sections with the same name should simply be discarded. */ + #define SEC_LINK_DUPLICATES_DISCARD 0x0 + + /* This value for SEC_LINK_DUPLICATES means that the linker + should warn if there are any duplicate sections, although + it should still only link one copy. */ + #define SEC_LINK_DUPLICATES_ONE_ONLY 0x40000 + + /* This value for SEC_LINK_DUPLICATES means that the linker + should warn if any duplicate sections are a different size. */ + #define SEC_LINK_DUPLICATES_SAME_SIZE 0x80000 + + /* This value for SEC_LINK_DUPLICATES means that the linker + should warn if any duplicate sections contain different + contents. */ + #define SEC_LINK_DUPLICATES_SAME_CONTENTS \ + (SEC_LINK_DUPLICATES_ONE_ONLY | SEC_LINK_DUPLICATES_SAME_SIZE) + + /* This section was created by the linker as part of dynamic + relocation or other arcane processing. It is skipped when + going through the first-pass output, trusting that someone + else up the line will take care of it later. */ + #define SEC_LINKER_CREATED 0x100000 + + /* This section should not be subject to garbage collection. + Also set to inform the linker that this section should not be + listed in the link map as discarded. */ + #define SEC_KEEP 0x200000 + + /* This section contains "short" data, and should be placed + "near" the GP. */ + #define SEC_SMALL_DATA 0x400000 + + /* Attempt to merge identical entities in the section. + Entity size is given in the entsize field. */ + #define SEC_MERGE 0x800000 + + /* If given with SEC_MERGE, entities to merge are zero terminated + strings where entsize specifies character size instead of fixed + size entries. */ + #define SEC_STRINGS 0x1000000 + + /* This section contains data about section groups. */ + #define SEC_GROUP 0x2000000 + + /* The section is a COFF shared library section. This flag is + only for the linker. If this type of section appears in + the input file, the linker must copy it to the output file + without changing the vma or size. FIXME: Although this + was originally intended to be general, it really is COFF + specific (and the flag was renamed to indicate this). It + might be cleaner to have some more general mechanism to + allow the back end to control what the linker does with + sections. */ + #define SEC_COFF_SHARED_LIBRARY 0x4000000 + + /* This section contains data which may be shared with other + executables or shared objects. This is for COFF only. */ + #define SEC_COFF_SHARED 0x8000000 + + /* When a section with this flag is being linked, then if the size of + the input section is less than a page, it should not cross a page + boundary. If the size of the input section is one page or more, + it should be aligned on a page boundary. This is for TI + TMS320C54X only. */ + #define SEC_TIC54X_BLOCK 0x10000000 + + /* Conditionally link this section; do not link if there are no + references found to any symbol in the section. This is for TI + TMS320C54X only. */ + #define SEC_TIC54X_CLINK 0x20000000 + + /* Indicate that section has the no read flag set. This happens + when memory read flag isn't set. */ + #define SEC_COFF_NOREAD 0x40000000 + + /* End of section flags. */ + + /* Some internal packed boolean fields. */ + + /* See the vma field. */ + unsigned int user_set_vma : 1; + + /* A mark flag used by some of the linker backends. */ + unsigned int linker_mark : 1; + + /* Another mark flag used by some of the linker backends. Set for + output sections that have an input section. */ + unsigned int linker_has_input : 1; + + /* Mark flag used by some linker backends for garbage collection. */ + unsigned int gc_mark : 1; + + /* The following flags are used by the ELF linker. */ + + /* Mark sections which have been allocated to segments. */ + unsigned int segment_mark : 1; + + /* Type of sec_info information. */ + unsigned int sec_info_type:3; + #define ELF_INFO_TYPE_NONE 0 + #define ELF_INFO_TYPE_STABS 1 + #define ELF_INFO_TYPE_MERGE 2 + #define ELF_INFO_TYPE_EH_FRAME 3 + #define ELF_INFO_TYPE_JUST_SYMS 4 + + /* Nonzero if this section uses RELA relocations, rather than REL. */ + unsigned int use_rela_p:1; + + /* Bits used by various backends. The generic code doesn't touch + these fields. */ + + /* Nonzero if this section has TLS related relocations. */ + unsigned int has_tls_reloc:1; + + /* Nonzero if this section has a call to __tls_get_addr. */ + unsigned int has_tls_get_addr_call:1; + + /* Nonzero if this section has a gp reloc. */ + unsigned int has_gp_reloc:1; + + /* Nonzero if this section needs the relax finalize pass. */ + unsigned int need_finalize_relax:1; + + /* Whether relocations have been processed. */ + unsigned int reloc_done : 1; + + /* End of internal packed boolean fields. */ + + /* The virtual memory address of the section - where it will be + at run time. The symbols are relocated against this. The + user_set_vma flag is maintained by bfd; if it's not set, the + backend can assign addresses (for example, in `a.out', where + the default address for `.data' is dependent on the specific + target and various flags). */ + bfd_vma vma; + + /* The load address of the section - where it would be in a + rom image; really only used for writing section header + information. */ + bfd_vma lma; + + /* The size of the section in octets, as it will be output. + Contains a value even if the section has no contents (e.g., the + size of `.bss'). */ + bfd_size_type size; + + /* For input sections, the original size on disk of the section, in + octets. This field should be set for any section whose size is + changed by linker relaxation. It is required for sections where + the linker relaxation scheme doesn't cache altered section and + reloc contents (stabs, eh_frame, SEC_MERGE, some coff relaxing + targets), and thus the original size needs to be kept to read the + section multiple times. For output sections, rawsize holds the + section size calculated on a previous linker relaxation pass. */ + bfd_size_type rawsize; + + /* Relaxation table. */ + struct relax_table *relax; + + /* Count of used relaxation table entries. */ + int relax_count; + + + /* If this section is going to be output, then this value is the + offset in *bytes* into the output section of the first byte in the + input section (byte ==> smallest addressable unit on the + target). In most cases, if this was going to start at the + 100th octet (8-bit quantity) in the output section, this value + would be 100. However, if the target byte size is 16 bits + (bfd_octets_per_byte is "2"), this value would be 50. */ + bfd_vma output_offset; + + /* The output section through which to map on output. */ + struct bfd_section *output_section; + + /* The alignment requirement of the section, as an exponent of 2 - + e.g., 3 aligns to 2^3 (or 8). */ + unsigned int alignment_power; + + /* If an input section, a pointer to a vector of relocation + records for the data in this section. */ + struct reloc_cache_entry *relocation; + + /* If an output section, a pointer to a vector of pointers to + relocation records for the data in this section. */ + struct reloc_cache_entry **orelocation; + + /* The number of relocation records in one of the above. */ + unsigned reloc_count; + + /* Information below is back end specific - and not always used + or updated. */ + + /* File position of section data. */ + file_ptr filepos; + + /* File position of relocation info. */ + file_ptr rel_filepos; + + /* File position of line data. */ + file_ptr line_filepos; + + /* Pointer to data for applications. */ + void *userdata; + + /* If the SEC_IN_MEMORY flag is set, this points to the actual + contents. */ + unsigned char *contents; + + /* Attached line number information. */ + alent *lineno; + + /* Number of line number records. */ + unsigned int lineno_count; + + /* Entity size for merging purposes. */ + unsigned int entsize; + + /* Points to the kept section if this section is a link-once section, + and is discarded. */ + struct bfd_section *kept_section; + + /* When a section is being output, this value changes as more + linenumbers are written out. */ + file_ptr moving_line_filepos; + + /* What the section number is in the target world. */ + int target_index; + + void *used_by_bfd; + + /* If this is a constructor section then here is a list of the + relocations created to relocate items within it. */ + struct relent_chain *constructor_chain; + + /* The BFD which owns the section. */ + bfd *owner; + + /* A symbol which points at this section only. */ + struct bfd_symbol *symbol; + struct bfd_symbol **symbol_ptr_ptr; + + /* Early in the link process, map_head and map_tail are used to build + a list of input sections attached to an output section. Later, + output sections use these fields for a list of bfd_link_order + structs. */ + union { + struct bfd_link_order *link_order; + struct bfd_section *s; + } map_head, map_tail; + } asection; + + /* Relax table contains information about instructions which can + be removed by relaxation -- replacing a long address with a + short address. */ + struct relax_table { + /* Address where bytes may be deleted. */ + bfd_vma addr; + + /* Number of bytes to be deleted. */ + int size; + }; + + /* These sections are global, and are managed by BFD. The application + and target back end are not permitted to change the values in + these sections. New code should use the section_ptr macros rather + than referring directly to the const sections. The const sections + may eventually vanish. */ + #define BFD_ABS_SECTION_NAME "*ABS*" + #define BFD_UND_SECTION_NAME "*UND*" + #define BFD_COM_SECTION_NAME "*COM*" + #define BFD_IND_SECTION_NAME "*IND*" + + /* The absolute section. */ + extern asection bfd_abs_section; + #define bfd_abs_section_ptr ((asection *) &bfd_abs_section) + #define bfd_is_abs_section(sec) ((sec) == bfd_abs_section_ptr) + /* Pointer to the undefined section. */ + extern asection bfd_und_section; + #define bfd_und_section_ptr ((asection *) &bfd_und_section) + #define bfd_is_und_section(sec) ((sec) == bfd_und_section_ptr) + /* Pointer to the common section. */ + extern asection bfd_com_section; + #define bfd_com_section_ptr ((asection *) &bfd_com_section) + /* Pointer to the indirect section. */ + extern asection bfd_ind_section; + #define bfd_ind_section_ptr ((asection *) &bfd_ind_section) + #define bfd_is_ind_section(sec) ((sec) == bfd_ind_section_ptr) + + #define bfd_is_const_section(SEC) \ + ( ((SEC) == bfd_abs_section_ptr) \ + || ((SEC) == bfd_und_section_ptr) \ + || ((SEC) == bfd_com_section_ptr) \ + || ((SEC) == bfd_ind_section_ptr)) + + /* Macros to handle insertion and deletion of a bfd's sections. These + only handle the list pointers, ie. do not adjust section_count, + target_index etc. */ + #define bfd_section_list_remove(ABFD, S) \ + do \ + { \ + asection *_s = S; \ + asection *_next = _s->next; \ + asection *_prev = _s->prev; \ + if (_prev) \ + _prev->next = _next; \ + else \ + (ABFD)->sections = _next; \ + if (_next) \ + _next->prev = _prev; \ + else \ + (ABFD)->section_last = _prev; \ + } \ + while (0) + #define bfd_section_list_append(ABFD, S) \ + do \ + { \ + asection *_s = S; \ + bfd *_abfd = ABFD; \ + _s->next = NULL; \ + if (_abfd->section_last) \ + { \ + _s->prev = _abfd->section_last; \ + _abfd->section_last->next = _s; \ + } \ + else \ + { \ + _s->prev = NULL; \ + _abfd->sections = _s; \ + } \ + _abfd->section_last = _s; \ + } \ + while (0) + #define bfd_section_list_prepend(ABFD, S) \ + do \ + { \ + asection *_s = S; \ + bfd *_abfd = ABFD; \ + _s->prev = NULL; \ + if (_abfd->sections) \ + { \ + _s->next = _abfd->sections; \ + _abfd->sections->prev = _s; \ + } \ + else \ + { \ + _s->next = NULL; \ + _abfd->section_last = _s; \ + } \ + _abfd->sections = _s; \ + } \ + while (0) + #define bfd_section_list_insert_after(ABFD, A, S) \ + do \ + { \ + asection *_a = A; \ + asection *_s = S; \ + asection *_next = _a->next; \ + _s->next = _next; \ + _s->prev = _a; \ + _a->next = _s; \ + if (_next) \ + _next->prev = _s; \ + else \ + (ABFD)->section_last = _s; \ + } \ + while (0) + #define bfd_section_list_insert_before(ABFD, B, S) \ + do \ + { \ + asection *_b = B; \ + asection *_s = S; \ + asection *_prev = _b->prev; \ + _s->prev = _prev; \ + _s->next = _b; \ + _b->prev = _s; \ + if (_prev) \ + _prev->next = _s; \ + else \ + (ABFD)->sections = _s; \ + } \ + while (0) + #define bfd_section_removed_from_list(ABFD, S) \ + ((S)->next == NULL ? (ABFD)->section_last != (S) : (S)->next->prev != (S)) + + #define BFD_FAKE_SECTION(SEC, FLAGS, SYM, NAME, IDX) \ + /* name, id, index, next, prev, flags, user_set_vma, */ \ + { NAME, IDX, 0, NULL, NULL, FLAGS, 0, \ + \ + /* linker_mark, linker_has_input, gc_mark, */ \ + 0, 0, 1, \ + \ + /* segment_mark, sec_info_type, use_rela_p, has_tls_reloc, */ \ + 0, 0, 0, 0, \ + \ + /* has_tls_get_addr_call, has_gp_reloc, need_finalize_relax, */ \ + 0, 0, 0, \ + \ + /* reloc_done, vma, lma, size, rawsize, relax, relax_count, */ \ + 0, 0, 0, 0, 0, 0, 0, \ + \ + /* output_offset, output_section, alignment_power, */ \ + 0, (struct bfd_section *) &SEC, 0, \ + \ + /* relocation, orelocation, reloc_count, filepos, rel_filepos, */ \ + NULL, NULL, 0, 0, 0, \ + \ + /* line_filepos, userdata, contents, lineno, lineno_count, */ \ + 0, NULL, NULL, NULL, 0, \ + \ + /* entsize, kept_section, moving_line_filepos, */ \ + 0, NULL, 0, \ + \ + /* target_index, used_by_bfd, constructor_chain, owner, */ \ + 0, NULL, NULL, NULL, \ + \ + /* symbol, symbol_ptr_ptr, */ \ + (struct bfd_symbol *) SYM, &SEC.symbol, \ + \ + /* map_head, map_tail */ \ + { NULL }, { NULL } \ + } + + +File: bfd.info, Node: section prototypes, Prev: typedef asection, Up: Sections + +2.6.5 Section prototypes +------------------------ + +These are the functions exported by the section handling part of BFD. + +2.6.5.1 `bfd_section_list_clear' +................................ + +*Synopsis* + void bfd_section_list_clear (bfd *); + *Description* +Clears the section list, and also resets the section count and hash +table entries. + +2.6.5.2 `bfd_get_section_by_name' +................................. + +*Synopsis* + asection *bfd_get_section_by_name (bfd *abfd, const char *name); + *Description* +Run through ABFD and return the one of the `asection's whose name +matches NAME, otherwise `NULL'. *Note Sections::, for more information. + + This should only be used in special cases; the normal way to process +all sections of a given name is to use `bfd_map_over_sections' and +`strcmp' on the name (or better yet, base it on the section flags or +something else) for each section. + +2.6.5.3 `bfd_get_section_by_name_if' +.................................... + +*Synopsis* + asection *bfd_get_section_by_name_if + (bfd *abfd, + const char *name, + bfd_boolean (*func) (bfd *abfd, asection *sect, void *obj), + void *obj); + *Description* +Call the provided function FUNC for each section attached to the BFD +ABFD whose name matches NAME, passing OBJ as an argument. The function +will be called as if by + + func (abfd, the_section, obj); + + It returns the first section for which FUNC returns true, otherwise +`NULL'. + +2.6.5.4 `bfd_get_unique_section_name' +..................................... + +*Synopsis* + char *bfd_get_unique_section_name + (bfd *abfd, const char *templat, int *count); + *Description* +Invent a section name that is unique in ABFD by tacking a dot and a +digit suffix onto the original TEMPLAT. If COUNT is non-NULL, then it +specifies the first number tried as a suffix to generate a unique name. +The value pointed to by COUNT will be incremented in this case. + +2.6.5.5 `bfd_make_section_old_way' +.................................. + +*Synopsis* + asection *bfd_make_section_old_way (bfd *abfd, const char *name); + *Description* +Create a new empty section called NAME and attach it to the end of the +chain of sections for the BFD ABFD. An attempt to create a section with +a name which is already in use returns its pointer without changing the +section chain. + + It has the funny name since this is the way it used to be before it +was rewritten.... + + Possible errors are: + * `bfd_error_invalid_operation' - If output has already started for + this BFD. + + * `bfd_error_no_memory' - If memory allocation fails. + +2.6.5.6 `bfd_make_section_anyway_with_flags' +............................................ + +*Synopsis* + asection *bfd_make_section_anyway_with_flags + (bfd *abfd, const char *name, flagword flags); + *Description* +Create a new empty section called NAME and attach it to the end of the +chain of sections for ABFD. Create a new section even if there is +already a section with that name. Also set the attributes of the new +section to the value FLAGS. + + Return `NULL' and set `bfd_error' on error; possible errors are: + * `bfd_error_invalid_operation' - If output has already started for + ABFD. + + * `bfd_error_no_memory' - If memory allocation fails. + +2.6.5.7 `bfd_make_section_anyway' +................................. + +*Synopsis* + asection *bfd_make_section_anyway (bfd *abfd, const char *name); + *Description* +Create a new empty section called NAME and attach it to the end of the +chain of sections for ABFD. Create a new section even if there is +already a section with that name. + + Return `NULL' and set `bfd_error' on error; possible errors are: + * `bfd_error_invalid_operation' - If output has already started for + ABFD. + + * `bfd_error_no_memory' - If memory allocation fails. + +2.6.5.8 `bfd_make_section_with_flags' +..................................... + +*Synopsis* + asection *bfd_make_section_with_flags + (bfd *, const char *name, flagword flags); + *Description* +Like `bfd_make_section_anyway', but return `NULL' (without calling +bfd_set_error ()) without changing the section chain if there is +already a section named NAME. Also set the attributes of the new +section to the value FLAGS. If there is an error, return `NULL' and set +`bfd_error'. + +2.6.5.9 `bfd_make_section' +.......................... + +*Synopsis* + asection *bfd_make_section (bfd *, const char *name); + *Description* +Like `bfd_make_section_anyway', but return `NULL' (without calling +bfd_set_error ()) without changing the section chain if there is +already a section named NAME. If there is an error, return `NULL' and +set `bfd_error'. + +2.6.5.10 `bfd_set_section_flags' +................................ + +*Synopsis* + bfd_boolean bfd_set_section_flags + (bfd *abfd, asection *sec, flagword flags); + *Description* +Set the attributes of the section SEC in the BFD ABFD to the value +FLAGS. Return `TRUE' on success, `FALSE' on error. Possible error +returns are: + + * `bfd_error_invalid_operation' - The section cannot have one or + more of the attributes requested. For example, a .bss section in + `a.out' may not have the `SEC_HAS_CONTENTS' field set. + +2.6.5.11 `bfd_map_over_sections' +................................ + +*Synopsis* + void bfd_map_over_sections + (bfd *abfd, + void (*func) (bfd *abfd, asection *sect, void *obj), + void *obj); + *Description* +Call the provided function FUNC for each section attached to the BFD +ABFD, passing OBJ as an argument. The function will be called as if by + + func (abfd, the_section, obj); + + This is the preferred method for iterating over sections; an +alternative would be to use a loop: + + section *p; + for (p = abfd->sections; p != NULL; p = p->next) + func (abfd, p, ...) + +2.6.5.12 `bfd_sections_find_if' +............................... + +*Synopsis* + asection *bfd_sections_find_if + (bfd *abfd, + bfd_boolean (*operation) (bfd *abfd, asection *sect, void *obj), + void *obj); + *Description* +Call the provided function OPERATION for each section attached to the +BFD ABFD, passing OBJ as an argument. The function will be called as if +by + + operation (abfd, the_section, obj); + + It returns the first section for which OPERATION returns true. + +2.6.5.13 `bfd_set_section_size' +............................... + +*Synopsis* + bfd_boolean bfd_set_section_size + (bfd *abfd, asection *sec, bfd_size_type val); + *Description* +Set SEC to the size VAL. If the operation is ok, then `TRUE' is +returned, else `FALSE'. + + Possible error returns: + * `bfd_error_invalid_operation' - Writing has started to the BFD, so + setting the size is invalid. + +2.6.5.14 `bfd_set_section_contents' +................................... + +*Synopsis* + bfd_boolean bfd_set_section_contents + (bfd *abfd, asection *section, const void *data, + file_ptr offset, bfd_size_type count); + *Description* +Sets the contents of the section SECTION in BFD ABFD to the data +starting in memory at DATA. The data is written to the output section +starting at offset OFFSET for COUNT octets. + + Normally `TRUE' is returned, else `FALSE'. Possible error returns +are: + * `bfd_error_no_contents' - The output section does not have the + `SEC_HAS_CONTENTS' attribute, so nothing can be written to it. + + * and some more too + This routine is front end to the back end function +`_bfd_set_section_contents'. + +2.6.5.15 `bfd_get_section_contents' +................................... + +*Synopsis* + bfd_boolean bfd_get_section_contents + (bfd *abfd, asection *section, void *location, file_ptr offset, + bfd_size_type count); + *Description* +Read data from SECTION in BFD ABFD into memory starting at LOCATION. +The data is read at an offset of OFFSET from the start of the input +section, and is read for COUNT bytes. + + If the contents of a constructor with the `SEC_CONSTRUCTOR' flag set +are requested or if the section does not have the `SEC_HAS_CONTENTS' +flag set, then the LOCATION is filled with zeroes. If no errors occur, +`TRUE' is returned, else `FALSE'. + +2.6.5.16 `bfd_malloc_and_get_section' +..................................... + +*Synopsis* + bfd_boolean bfd_malloc_and_get_section + (bfd *abfd, asection *section, bfd_byte **buf); + *Description* +Read all data from SECTION in BFD ABFD into a buffer, *BUF, malloc'd by +this function. + +2.6.5.17 `bfd_copy_private_section_data' +........................................ + +*Synopsis* + bfd_boolean bfd_copy_private_section_data + (bfd *ibfd, asection *isec, bfd *obfd, asection *osec); + *Description* +Copy private section information from ISEC in the BFD IBFD to the +section OSEC in the BFD OBFD. Return `TRUE' on success, `FALSE' on +error. Possible error returns are: + + * `bfd_error_no_memory' - Not enough memory exists to create private + data for OSEC. + + #define bfd_copy_private_section_data(ibfd, isection, obfd, osection) \ + BFD_SEND (obfd, _bfd_copy_private_section_data, \ + (ibfd, isection, obfd, osection)) + +2.6.5.18 `bfd_generic_is_group_section' +....................................... + +*Synopsis* + bfd_boolean bfd_generic_is_group_section (bfd *, const asection *sec); + *Description* +Returns TRUE if SEC is a member of a group. + +2.6.5.19 `bfd_generic_discard_group' +.................................... + +*Synopsis* + bfd_boolean bfd_generic_discard_group (bfd *abfd, asection *group); + *Description* +Remove all members of GROUP from the output. + + +File: bfd.info, Node: Symbols, Next: Archives, Prev: Sections, Up: BFD front end + +2.7 Symbols +=========== + +BFD tries to maintain as much symbol information as it can when it +moves information from file to file. BFD passes information to +applications though the `asymbol' structure. When the application +requests the symbol table, BFD reads the table in the native form and +translates parts of it into the internal format. To maintain more than +the information passed to applications, some targets keep some +information "behind the scenes" in a structure only the particular back +end knows about. For example, the coff back end keeps the original +symbol table structure as well as the canonical structure when a BFD is +read in. On output, the coff back end can reconstruct the output symbol +table so that no information is lost, even information unique to coff +which BFD doesn't know or understand. If a coff symbol table were read, +but were written through an a.out back end, all the coff specific +information would be lost. The symbol table of a BFD is not necessarily +read in until a canonicalize request is made. Then the BFD back end +fills in a table provided by the application with pointers to the +canonical information. To output symbols, the application provides BFD +with a table of pointers to pointers to `asymbol's. This allows +applications like the linker to output a symbol as it was read, since +the "behind the scenes" information will be still available. + +* Menu: + +* Reading Symbols:: +* Writing Symbols:: +* Mini Symbols:: +* typedef asymbol:: +* symbol handling functions:: + + +File: bfd.info, Node: Reading Symbols, Next: Writing Symbols, Prev: Symbols, Up: Symbols + +2.7.1 Reading symbols +--------------------- + +There are two stages to reading a symbol table from a BFD: allocating +storage, and the actual reading process. This is an excerpt from an +application which reads the symbol table: + + long storage_needed; + asymbol **symbol_table; + long number_of_symbols; + long i; + + storage_needed = bfd_get_symtab_upper_bound (abfd); + + if (storage_needed < 0) + FAIL + + if (storage_needed == 0) + return; + + symbol_table = xmalloc (storage_needed); + ... + number_of_symbols = + bfd_canonicalize_symtab (abfd, symbol_table); + + if (number_of_symbols < 0) + FAIL + + for (i = 0; i < number_of_symbols; i++) + process_symbol (symbol_table[i]); + + All storage for the symbols themselves is in an objalloc connected +to the BFD; it is freed when the BFD is closed. + + +File: bfd.info, Node: Writing Symbols, Next: Mini Symbols, Prev: Reading Symbols, Up: Symbols + +2.7.2 Writing symbols +--------------------- + +Writing of a symbol table is automatic when a BFD open for writing is +closed. The application attaches a vector of pointers to pointers to +symbols to the BFD being written, and fills in the symbol count. The +close and cleanup code reads through the table provided and performs +all the necessary operations. The BFD output code must always be +provided with an "owned" symbol: one which has come from another BFD, +or one which has been created using `bfd_make_empty_symbol'. Here is an +example showing the creation of a symbol table with only one element: + + #include "bfd.h" + int main (void) + { + bfd *abfd; + asymbol *ptrs[2]; + asymbol *new; + + abfd = bfd_openw ("foo","a.out-sunos-big"); + bfd_set_format (abfd, bfd_object); + new = bfd_make_empty_symbol (abfd); + new->name = "dummy_symbol"; + new->section = bfd_make_section_old_way (abfd, ".text"); + new->flags = BSF_GLOBAL; + new->value = 0x12345; + + ptrs[0] = new; + ptrs[1] = 0; + + bfd_set_symtab (abfd, ptrs, 1); + bfd_close (abfd); + return 0; + } + + ./makesym + nm foo + 00012345 A dummy_symbol + + Many formats cannot represent arbitrary symbol information; for +instance, the `a.out' object format does not allow an arbitrary number +of sections. A symbol pointing to a section which is not one of +`.text', `.data' or `.bss' cannot be described. + + +File: bfd.info, Node: Mini Symbols, Next: typedef asymbol, Prev: Writing Symbols, Up: Symbols + +2.7.3 Mini Symbols +------------------ + +Mini symbols provide read-only access to the symbol table. They use +less memory space, but require more time to access. They can be useful +for tools like nm or objdump, which may have to handle symbol tables of +extremely large executables. + + The `bfd_read_minisymbols' function will read the symbols into +memory in an internal form. It will return a `void *' pointer to a +block of memory, a symbol count, and the size of each symbol. The +pointer is allocated using `malloc', and should be freed by the caller +when it is no longer needed. + + The function `bfd_minisymbol_to_symbol' will take a pointer to a +minisymbol, and a pointer to a structure returned by +`bfd_make_empty_symbol', and return a `asymbol' structure. The return +value may or may not be the same as the value from +`bfd_make_empty_symbol' which was passed in. + + +File: bfd.info, Node: typedef asymbol, Next: symbol handling functions, Prev: Mini Symbols, Up: Symbols + +2.7.4 typedef asymbol +--------------------- + +An `asymbol' has the form: + + + typedef struct bfd_symbol + { + /* A pointer to the BFD which owns the symbol. This information + is necessary so that a back end can work out what additional + information (invisible to the application writer) is carried + with the symbol. + + This field is *almost* redundant, since you can use section->owner + instead, except that some symbols point to the global sections + bfd_{abs,com,und}_section. This could be fixed by making + these globals be per-bfd (or per-target-flavor). FIXME. */ + struct bfd *the_bfd; /* Use bfd_asymbol_bfd(sym) to access this field. */ + + /* The text of the symbol. The name is left alone, and not copied; the + application may not alter it. */ + const char *name; + + /* The value of the symbol. This really should be a union of a + numeric value with a pointer, since some flags indicate that + a pointer to another symbol is stored here. */ + symvalue value; + + /* Attributes of a symbol. */ + #define BSF_NO_FLAGS 0x00 + + /* The symbol has local scope; `static' in `C'. The value + is the offset into the section of the data. */ + #define BSF_LOCAL (1 << 0) + + /* The symbol has global scope; initialized data in `C'. The + value is the offset into the section of the data. */ + #define BSF_GLOBAL (1 << 1) + + /* The symbol has global scope and is exported. The value is + the offset into the section of the data. */ + #define BSF_EXPORT BSF_GLOBAL /* No real difference. */ + + /* A normal C symbol would be one of: + `BSF_LOCAL', `BSF_COMMON', `BSF_UNDEFINED' or + `BSF_GLOBAL'. */ + + /* The symbol is a debugging record. The value has an arbitrary + meaning, unless BSF_DEBUGGING_RELOC is also set. */ + #define BSF_DEBUGGING (1 << 2) + + /* The symbol denotes a function entry point. Used in ELF, + perhaps others someday. */ + #define BSF_FUNCTION (1 << 3) + + /* Used by the linker. */ + #define BSF_KEEP (1 << 5) + #define BSF_KEEP_G (1 << 6) + + /* A weak global symbol, overridable without warnings by + a regular global symbol of the same name. */ + #define BSF_WEAK (1 << 7) + + /* This symbol was created to point to a section, e.g. ELF's + STT_SECTION symbols. */ + #define BSF_SECTION_SYM (1 << 8) + + /* The symbol used to be a common symbol, but now it is + allocated. */ + #define BSF_OLD_COMMON (1 << 9) + + /* In some files the type of a symbol sometimes alters its + location in an output file - ie in coff a `ISFCN' symbol + which is also `C_EXT' symbol appears where it was + declared and not at the end of a section. This bit is set + by the target BFD part to convey this information. */ + #define BSF_NOT_AT_END (1 << 10) + + /* Signal that the symbol is the label of constructor section. */ + #define BSF_CONSTRUCTOR (1 << 11) + + /* Signal that the symbol is a warning symbol. The name is a + warning. The name of the next symbol is the one to warn about; + if a reference is made to a symbol with the same name as the next + symbol, a warning is issued by the linker. */ + #define BSF_WARNING (1 << 12) + + /* Signal that the symbol is indirect. This symbol is an indirect + pointer to the symbol with the same name as the next symbol. */ + #define BSF_INDIRECT (1 << 13) + + /* BSF_FILE marks symbols that contain a file name. This is used + for ELF STT_FILE symbols. */ + #define BSF_FILE (1 << 14) + + /* Symbol is from dynamic linking information. */ + #define BSF_DYNAMIC (1 << 15) + + /* The symbol denotes a data object. Used in ELF, and perhaps + others someday. */ + #define BSF_OBJECT (1 << 16) + + /* This symbol is a debugging symbol. The value is the offset + into the section of the data. BSF_DEBUGGING should be set + as well. */ + #define BSF_DEBUGGING_RELOC (1 << 17) + + /* This symbol is thread local. Used in ELF. */ + #define BSF_THREAD_LOCAL (1 << 18) + + /* This symbol represents a complex relocation expression, + with the expression tree serialized in the symbol name. */ + #define BSF_RELC (1 << 19) + + /* This symbol represents a signed complex relocation expression, + with the expression tree serialized in the symbol name. */ + #define BSF_SRELC (1 << 20) + + /* This symbol was created by bfd_get_synthetic_symtab. */ + #define BSF_SYNTHETIC (1 << 21) + + /* This symbol is an indirect code object. Unrelated to BSF_INDIRECT. + The dynamic linker will compute the value of this symbol by + calling the function that it points to. BSF_FUNCTION must + also be also set. */ + #define BSF_GNU_INDIRECT_FUNCTION (1 << 22) + /* This symbol is a globally unique data object. The dynamic linker + will make sure that in the entire process there is just one symbol + with this name and type in use. BSF_OBJECT must also be set. */ + #define BSF_GNU_UNIQUE (1 << 23) + + flagword flags; + + /* A pointer to the section to which this symbol is + relative. This will always be non NULL, there are special + sections for undefined and absolute symbols. */ + struct bfd_section *section; + + /* Back end special data. */ + union + { + void *p; + bfd_vma i; + } + udata; + } + asymbol; + + +File: bfd.info, Node: symbol handling functions, Prev: typedef asymbol, Up: Symbols + +2.7.5 Symbol handling functions +------------------------------- + +2.7.5.1 `bfd_get_symtab_upper_bound' +.................................... + +*Description* +Return the number of bytes required to store a vector of pointers to +`asymbols' for all the symbols in the BFD ABFD, including a terminal +NULL pointer. If there are no symbols in the BFD, then return 0. If an +error occurs, return -1. + #define bfd_get_symtab_upper_bound(abfd) \ + BFD_SEND (abfd, _bfd_get_symtab_upper_bound, (abfd)) + +2.7.5.2 `bfd_is_local_label' +............................ + +*Synopsis* + bfd_boolean bfd_is_local_label (bfd *abfd, asymbol *sym); + *Description* +Return TRUE if the given symbol SYM in the BFD ABFD is a compiler +generated local label, else return FALSE. + +2.7.5.3 `bfd_is_local_label_name' +................................. + +*Synopsis* + bfd_boolean bfd_is_local_label_name (bfd *abfd, const char *name); + *Description* +Return TRUE if a symbol with the name NAME in the BFD ABFD is a +compiler generated local label, else return FALSE. This just checks +whether the name has the form of a local label. + #define bfd_is_local_label_name(abfd, name) \ + BFD_SEND (abfd, _bfd_is_local_label_name, (abfd, name)) + +2.7.5.4 `bfd_is_target_special_symbol' +...................................... + +*Synopsis* + bfd_boolean bfd_is_target_special_symbol (bfd *abfd, asymbol *sym); + *Description* +Return TRUE iff a symbol SYM in the BFD ABFD is something special to +the particular target represented by the BFD. Such symbols should +normally not be mentioned to the user. + #define bfd_is_target_special_symbol(abfd, sym) \ + BFD_SEND (abfd, _bfd_is_target_special_symbol, (abfd, sym)) + +2.7.5.5 `bfd_canonicalize_symtab' +................................. + +*Description* +Read the symbols from the BFD ABFD, and fills in the vector LOCATION +with pointers to the symbols and a trailing NULL. Return the actual +number of symbol pointers, not including the NULL. + #define bfd_canonicalize_symtab(abfd, location) \ + BFD_SEND (abfd, _bfd_canonicalize_symtab, (abfd, location)) + +2.7.5.6 `bfd_set_symtab' +........................ + +*Synopsis* + bfd_boolean bfd_set_symtab + (bfd *abfd, asymbol **location, unsigned int count); + *Description* +Arrange that when the output BFD ABFD is closed, the table LOCATION of +COUNT pointers to symbols will be written. + +2.7.5.7 `bfd_print_symbol_vandf' +................................ + +*Synopsis* + void bfd_print_symbol_vandf (bfd *abfd, void *file, asymbol *symbol); + *Description* +Print the value and flags of the SYMBOL supplied to the stream FILE. + +2.7.5.8 `bfd_make_empty_symbol' +............................... + +*Description* +Create a new `asymbol' structure for the BFD ABFD and return a pointer +to it. + + This routine is necessary because each back end has private +information surrounding the `asymbol'. Building your own `asymbol' and +pointing to it will not create the private information, and will cause +problems later on. + #define bfd_make_empty_symbol(abfd) \ + BFD_SEND (abfd, _bfd_make_empty_symbol, (abfd)) + +2.7.5.9 `_bfd_generic_make_empty_symbol' +........................................ + +*Synopsis* + asymbol *_bfd_generic_make_empty_symbol (bfd *); + *Description* +Create a new `asymbol' structure for the BFD ABFD and return a pointer +to it. Used by core file routines, binary back-end and anywhere else +where no private info is needed. + +2.7.5.10 `bfd_make_debug_symbol' +................................ + +*Description* +Create a new `asymbol' structure for the BFD ABFD, to be used as a +debugging symbol. Further details of its use have yet to be worked out. + #define bfd_make_debug_symbol(abfd,ptr,size) \ + BFD_SEND (abfd, _bfd_make_debug_symbol, (abfd, ptr, size)) + +2.7.5.11 `bfd_decode_symclass' +.............................. + +*Description* +Return a character corresponding to the symbol class of SYMBOL, or '?' +for an unknown class. + + *Synopsis* + int bfd_decode_symclass (asymbol *symbol); + +2.7.5.12 `bfd_is_undefined_symclass' +.................................... + +*Description* +Returns non-zero if the class symbol returned by bfd_decode_symclass +represents an undefined symbol. Returns zero otherwise. + + *Synopsis* + bfd_boolean bfd_is_undefined_symclass (int symclass); + +2.7.5.13 `bfd_symbol_info' +.......................... + +*Description* +Fill in the basic info about symbol that nm needs. Additional info may +be added by the back-ends after calling this function. + + *Synopsis* + void bfd_symbol_info (asymbol *symbol, symbol_info *ret); + +2.7.5.14 `bfd_copy_private_symbol_data' +....................................... + +*Synopsis* + bfd_boolean bfd_copy_private_symbol_data + (bfd *ibfd, asymbol *isym, bfd *obfd, asymbol *osym); + *Description* +Copy private symbol information from ISYM in the BFD IBFD to the symbol +OSYM in the BFD OBFD. Return `TRUE' on success, `FALSE' on error. +Possible error returns are: + + * `bfd_error_no_memory' - Not enough memory exists to create private + data for OSEC. + + #define bfd_copy_private_symbol_data(ibfd, isymbol, obfd, osymbol) \ + BFD_SEND (obfd, _bfd_copy_private_symbol_data, \ + (ibfd, isymbol, obfd, osymbol)) + + +File: bfd.info, Node: Archives, Next: Formats, Prev: Symbols, Up: BFD front end + +2.8 Archives +============ + +*Description* +An archive (or library) is just another BFD. It has a symbol table, +although there's not much a user program will do with it. + + The big difference between an archive BFD and an ordinary BFD is +that the archive doesn't have sections. Instead it has a chain of BFDs +that are considered its contents. These BFDs can be manipulated like +any other. The BFDs contained in an archive opened for reading will +all be opened for reading. You may put either input or output BFDs +into an archive opened for output; they will be handled correctly when +the archive is closed. + + Use `bfd_openr_next_archived_file' to step through the contents of +an archive opened for input. You don't have to read the entire archive +if you don't want to! Read it until you find what you want. + + Archive contents of output BFDs are chained through the `next' +pointer in a BFD. The first one is findable through the `archive_head' +slot of the archive. Set it with `bfd_set_archive_head' (q.v.). A +given BFD may be in only one open output archive at a time. + + As expected, the BFD archive code is more general than the archive +code of any given environment. BFD archives may contain files of +different formats (e.g., a.out and coff) and even different +architectures. You may even place archives recursively into archives! + + This can cause unexpected confusion, since some archive formats are +more expressive than others. For instance, Intel COFF archives can +preserve long filenames; SunOS a.out archives cannot. If you move a +file from the first to the second format and back again, the filename +may be truncated. Likewise, different a.out environments have different +conventions as to how they truncate filenames, whether they preserve +directory names in filenames, etc. When interoperating with native +tools, be sure your files are homogeneous. + + Beware: most of these formats do not react well to the presence of +spaces in filenames. We do the best we can, but can't always handle +this case due to restrictions in the format of archives. Many Unix +utilities are braindead in regards to spaces and such in filenames +anyway, so this shouldn't be much of a restriction. + + Archives are supported in BFD in `archive.c'. + +2.8.1 Archive functions +----------------------- + +2.8.1.1 `bfd_get_next_mapent' +............................. + +*Synopsis* + symindex bfd_get_next_mapent + (bfd *abfd, symindex previous, carsym **sym); + *Description* +Step through archive ABFD's symbol table (if it has one). Successively +update SYM with the next symbol's information, returning that symbol's +(internal) index into the symbol table. + + Supply `BFD_NO_MORE_SYMBOLS' as the PREVIOUS entry to get the first +one; returns `BFD_NO_MORE_SYMBOLS' when you've already got the last one. + + A `carsym' is a canonical archive symbol. The only user-visible +element is its name, a null-terminated string. + +2.8.1.2 `bfd_set_archive_head' +.............................. + +*Synopsis* + bfd_boolean bfd_set_archive_head (bfd *output, bfd *new_head); + *Description* +Set the head of the chain of BFDs contained in the archive OUTPUT to +NEW_HEAD. + +2.8.1.3 `bfd_openr_next_archived_file' +...................................... + +*Synopsis* + bfd *bfd_openr_next_archived_file (bfd *archive, bfd *previous); + *Description* +Provided a BFD, ARCHIVE, containing an archive and NULL, open an input +BFD on the first contained element and returns that. Subsequent calls +should pass the archive and the previous return value to return a +created BFD to the next contained element. NULL is returned when there +are no more. + + +File: bfd.info, Node: Formats, Next: Relocations, Prev: Archives, Up: BFD front end + +2.9 File formats +================ + +A format is a BFD concept of high level file contents type. The formats +supported by BFD are: + + * `bfd_object' + The BFD may contain data, symbols, relocations and debug info. + + * `bfd_archive' + The BFD contains other BFDs and an optional index. + + * `bfd_core' + The BFD contains the result of an executable core dump. + +2.9.1 File format functions +--------------------------- + +2.9.1.1 `bfd_check_format' +.......................... + +*Synopsis* + bfd_boolean bfd_check_format (bfd *abfd, bfd_format format); + *Description* +Verify if the file attached to the BFD ABFD is compatible with the +format FORMAT (i.e., one of `bfd_object', `bfd_archive' or `bfd_core'). + + If the BFD has been set to a specific target before the call, only +the named target and format combination is checked. If the target has +not been set, or has been set to `default', then all the known target +backends is interrogated to determine a match. If the default target +matches, it is used. If not, exactly one target must recognize the +file, or an error results. + + The function returns `TRUE' on success, otherwise `FALSE' with one +of the following error codes: + + * `bfd_error_invalid_operation' - if `format' is not one of + `bfd_object', `bfd_archive' or `bfd_core'. + + * `bfd_error_system_call' - if an error occured during a read - even + some file mismatches can cause bfd_error_system_calls. + + * `file_not_recognised' - none of the backends recognised the file + format. + + * `bfd_error_file_ambiguously_recognized' - more than one backend + recognised the file format. + +2.9.1.2 `bfd_check_format_matches' +.................................. + +*Synopsis* + bfd_boolean bfd_check_format_matches + (bfd *abfd, bfd_format format, char ***matching); + *Description* +Like `bfd_check_format', except when it returns FALSE with `bfd_errno' +set to `bfd_error_file_ambiguously_recognized'. In that case, if +MATCHING is not NULL, it will be filled in with a NULL-terminated list +of the names of the formats that matched, allocated with `malloc'. +Then the user may choose a format and try again. + + When done with the list that MATCHING points to, the caller should +free it. + +2.9.1.3 `bfd_set_format' +........................ + +*Synopsis* + bfd_boolean bfd_set_format (bfd *abfd, bfd_format format); + *Description* +This function sets the file format of the BFD ABFD to the format +FORMAT. If the target set in the BFD does not support the format +requested, the format is invalid, or the BFD is not open for writing, +then an error occurs. + +2.9.1.4 `bfd_format_string' +........................... + +*Synopsis* + const char *bfd_format_string (bfd_format format); + *Description* +Return a pointer to a const string `invalid', `object', `archive', +`core', or `unknown', depending upon the value of FORMAT. + + +File: bfd.info, Node: Relocations, Next: Core Files, Prev: Formats, Up: BFD front end + +2.10 Relocations +================ + +BFD maintains relocations in much the same way it maintains symbols: +they are left alone until required, then read in en-masse and +translated into an internal form. A common routine +`bfd_perform_relocation' acts upon the canonical form to do the fixup. + + Relocations are maintained on a per section basis, while symbols are +maintained on a per BFD basis. + + All that a back end has to do to fit the BFD interface is to create +a `struct reloc_cache_entry' for each relocation in a particular +section, and fill in the right bits of the structures. + +* Menu: + +* typedef arelent:: +* howto manager:: + + +File: bfd.info, Node: typedef arelent, Next: howto manager, Prev: Relocations, Up: Relocations + +2.10.1 typedef arelent +---------------------- + +This is the structure of a relocation entry: + + + typedef enum bfd_reloc_status + { + /* No errors detected. */ + bfd_reloc_ok, + + /* The relocation was performed, but there was an overflow. */ + bfd_reloc_overflow, + + /* The address to relocate was not within the section supplied. */ + bfd_reloc_outofrange, + + /* Used by special functions. */ + bfd_reloc_continue, + + /* Unsupported relocation size requested. */ + bfd_reloc_notsupported, + + /* Unused. */ + bfd_reloc_other, + + /* The symbol to relocate against was undefined. */ + bfd_reloc_undefined, + + /* The relocation was performed, but may not be ok - presently + generated only when linking i960 coff files with i960 b.out + symbols. If this type is returned, the error_message argument + to bfd_perform_relocation will be set. */ + bfd_reloc_dangerous + } + bfd_reloc_status_type; + + + typedef struct reloc_cache_entry + { + /* A pointer into the canonical table of pointers. */ + struct bfd_symbol **sym_ptr_ptr; + + /* offset in section. */ + bfd_size_type address; + + /* addend for relocation value. */ + bfd_vma addend; + + /* Pointer to how to perform the required relocation. */ + reloc_howto_type *howto; + + } + arelent; + *Description* +Here is a description of each of the fields within an `arelent': + + * `sym_ptr_ptr' + The symbol table pointer points to a pointer to the symbol +associated with the relocation request. It is the pointer into the +table returned by the back end's `canonicalize_symtab' action. *Note +Symbols::. The symbol is referenced through a pointer to a pointer so +that tools like the linker can fix up all the symbols of the same name +by modifying only one pointer. The relocation routine looks in the +symbol and uses the base of the section the symbol is attached to and +the value of the symbol as the initial relocation offset. If the symbol +pointer is zero, then the section provided is looked up. + + * `address' + The `address' field gives the offset in bytes from the base of the +section data which owns the relocation record to the first byte of +relocatable information. The actual data relocated will be relative to +this point; for example, a relocation type which modifies the bottom +two bytes of a four byte word would not touch the first byte pointed to +in a big endian world. + + * `addend' + The `addend' is a value provided by the back end to be added (!) to +the relocation offset. Its interpretation is dependent upon the howto. +For example, on the 68k the code: + + char foo[]; + main() + { + return foo[0x12345678]; + } + + Could be compiled into: + + linkw fp,#-4 + moveb @#12345678,d0 + extbl d0 + unlk fp + rts + + This could create a reloc pointing to `foo', but leave the offset in +the data, something like: + + RELOCATION RECORDS FOR [.text]: + offset type value + 00000006 32 _foo + + 00000000 4e56 fffc ; linkw fp,#-4 + 00000004 1039 1234 5678 ; moveb @#12345678,d0 + 0000000a 49c0 ; extbl d0 + 0000000c 4e5e ; unlk fp + 0000000e 4e75 ; rts + + Using coff and an 88k, some instructions don't have enough space in +them to represent the full address range, and pointers have to be +loaded in two parts. So you'd get something like: + + or.u r13,r0,hi16(_foo+0x12345678) + ld.b r2,r13,lo16(_foo+0x12345678) + jmp r1 + + This should create two relocs, both pointing to `_foo', and with +0x12340000 in their addend field. The data would consist of: + + RELOCATION RECORDS FOR [.text]: + offset type value + 00000002 HVRT16 _foo+0x12340000 + 00000006 LVRT16 _foo+0x12340000 + + 00000000 5da05678 ; or.u r13,r0,0x5678 + 00000004 1c4d5678 ; ld.b r2,r13,0x5678 + 00000008 f400c001 ; jmp r1 + + The relocation routine digs out the value from the data, adds it to +the addend to get the original offset, and then adds the value of +`_foo'. Note that all 32 bits have to be kept around somewhere, to cope +with carry from bit 15 to bit 16. + + One further example is the sparc and the a.out format. The sparc has +a similar problem to the 88k, in that some instructions don't have room +for an entire offset, but on the sparc the parts are created in odd +sized lumps. The designers of the a.out format chose to not use the +data within the section for storing part of the offset; all the offset +is kept within the reloc. Anything in the data should be ignored. + + save %sp,-112,%sp + sethi %hi(_foo+0x12345678),%g2 + ldsb [%g2+%lo(_foo+0x12345678)],%i0 + ret + restore + + Both relocs contain a pointer to `foo', and the offsets contain junk. + + RELOCATION RECORDS FOR [.text]: + offset type value + 00000004 HI22 _foo+0x12345678 + 00000008 LO10 _foo+0x12345678 + + 00000000 9de3bf90 ; save %sp,-112,%sp + 00000004 05000000 ; sethi %hi(_foo+0),%g2 + 00000008 f048a000 ; ldsb [%g2+%lo(_foo+0)],%i0 + 0000000c 81c7e008 ; ret + 00000010 81e80000 ; restore + + * `howto' + The `howto' field can be imagined as a relocation instruction. It is +a pointer to a structure which contains information on what to do with +all of the other information in the reloc record and data section. A +back end would normally have a relocation instruction set and turn +relocations into pointers to the correct structure on input - but it +would be possible to create each howto field on demand. + +2.10.1.1 `enum complain_overflow' +................................. + +Indicates what sort of overflow checking should be done when performing +a relocation. + + + enum complain_overflow + { + /* Do not complain on overflow. */ + complain_overflow_dont, + + /* Complain if the value overflows when considered as a signed + number one bit larger than the field. ie. A bitfield of N bits + is allowed to represent -2**n to 2**n-1. */ + complain_overflow_bitfield, + + /* Complain if the value overflows when considered as a signed + number. */ + complain_overflow_signed, + + /* Complain if the value overflows when considered as an + unsigned number. */ + complain_overflow_unsigned + }; + +2.10.1.2 `reloc_howto_type' +........................... + +The `reloc_howto_type' is a structure which contains all the +information that libbfd needs to know to tie up a back end's data. + + struct bfd_symbol; /* Forward declaration. */ + + struct reloc_howto_struct + { + /* The type field has mainly a documentary use - the back end can + do what it wants with it, though normally the back end's + external idea of what a reloc number is stored + in this field. For example, a PC relative word relocation + in a coff environment has the type 023 - because that's + what the outside world calls a R_PCRWORD reloc. */ + unsigned int type; + + /* The value the final relocation is shifted right by. This drops + unwanted data from the relocation. */ + unsigned int rightshift; + + /* The size of the item to be relocated. This is *not* a + power-of-two measure. To get the number of bytes operated + on by a type of relocation, use bfd_get_reloc_size. */ + int size; + + /* The number of bits in the item to be relocated. This is used + when doing overflow checking. */ + unsigned int bitsize; + + /* Notes that the relocation is relative to the location in the + data section of the addend. The relocation function will + subtract from the relocation value the address of the location + being relocated. */ + bfd_boolean pc_relative; + + /* The bit position of the reloc value in the destination. + The relocated value is left shifted by this amount. */ + unsigned int bitpos; + + /* What type of overflow error should be checked for when + relocating. */ + enum complain_overflow complain_on_overflow; + + /* If this field is non null, then the supplied function is + called rather than the normal function. This allows really + strange relocation methods to be accommodated (e.g., i960 callj + instructions). */ + bfd_reloc_status_type (*special_function) + (bfd *, arelent *, struct bfd_symbol *, void *, asection *, + bfd *, char **); + + /* The textual name of the relocation type. */ + char *name; + + /* Some formats record a relocation addend in the section contents + rather than with the relocation. For ELF formats this is the + distinction between USE_REL and USE_RELA (though the code checks + for USE_REL == 1/0). The value of this field is TRUE if the + addend is recorded with the section contents; when performing a + partial link (ld -r) the section contents (the data) will be + modified. The value of this field is FALSE if addends are + recorded with the relocation (in arelent.addend); when performing + a partial link the relocation will be modified. + All relocations for all ELF USE_RELA targets should set this field + to FALSE (values of TRUE should be looked on with suspicion). + However, the converse is not true: not all relocations of all ELF + USE_REL targets set this field to TRUE. Why this is so is peculiar + to each particular target. For relocs that aren't used in partial + links (e.g. GOT stuff) it doesn't matter what this is set to. */ + bfd_boolean partial_inplace; + + /* src_mask selects the part of the instruction (or data) to be used + in the relocation sum. If the target relocations don't have an + addend in the reloc, eg. ELF USE_REL, src_mask will normally equal + dst_mask to extract the addend from the section contents. If + relocations do have an addend in the reloc, eg. ELF USE_RELA, this + field should be zero. Non-zero values for ELF USE_RELA targets are + bogus as in those cases the value in the dst_mask part of the + section contents should be treated as garbage. */ + bfd_vma src_mask; + + /* dst_mask selects which parts of the instruction (or data) are + replaced with a relocated value. */ + bfd_vma dst_mask; + + /* When some formats create PC relative instructions, they leave + the value of the pc of the place being relocated in the offset + slot of the instruction, so that a PC relative relocation can + be made just by adding in an ordinary offset (e.g., sun3 a.out). + Some formats leave the displacement part of an instruction + empty (e.g., m88k bcs); this flag signals the fact. */ + bfd_boolean pcrel_offset; + }; + +2.10.1.3 `The HOWTO Macro' +.......................... + +*Description* +The HOWTO define is horrible and will go away. + #define HOWTO(C, R, S, B, P, BI, O, SF, NAME, INPLACE, MASKSRC, MASKDST, PC) \ + { (unsigned) C, R, S, B, P, BI, O, SF, NAME, INPLACE, MASKSRC, MASKDST, PC } + + *Description* +And will be replaced with the totally magic way. But for the moment, we +are compatible, so do it this way. + #define NEWHOWTO(FUNCTION, NAME, SIZE, REL, IN) \ + HOWTO (0, 0, SIZE, 0, REL, 0, complain_overflow_dont, FUNCTION, \ + NAME, FALSE, 0, 0, IN) + + *Description* +This is used to fill in an empty howto entry in an array. + #define EMPTY_HOWTO(C) \ + HOWTO ((C), 0, 0, 0, FALSE, 0, complain_overflow_dont, NULL, \ + NULL, FALSE, 0, 0, FALSE) + + *Description* +Helper routine to turn a symbol into a relocation value. + #define HOWTO_PREPARE(relocation, symbol) \ + { \ + if (symbol != NULL) \ + { \ + if (bfd_is_com_section (symbol->section)) \ + { \ + relocation = 0; \ + } \ + else \ + { \ + relocation = symbol->value; \ + } \ + } \ + } + +2.10.1.4 `bfd_get_reloc_size' +............................. + +*Synopsis* + unsigned int bfd_get_reloc_size (reloc_howto_type *); + *Description* +For a reloc_howto_type that operates on a fixed number of bytes, this +returns the number of bytes operated on. + +2.10.1.5 `arelent_chain' +........................ + +*Description* +How relocs are tied together in an `asection': + typedef struct relent_chain + { + arelent relent; + struct relent_chain *next; + } + arelent_chain; + +2.10.1.6 `bfd_check_overflow' +............................. + +*Synopsis* + bfd_reloc_status_type bfd_check_overflow + (enum complain_overflow how, + unsigned int bitsize, + unsigned int rightshift, + unsigned int addrsize, + bfd_vma relocation); + *Description* +Perform overflow checking on RELOCATION which has BITSIZE significant +bits and will be shifted right by RIGHTSHIFT bits, on a machine with +addresses containing ADDRSIZE significant bits. The result is either of +`bfd_reloc_ok' or `bfd_reloc_overflow'. + +2.10.1.7 `bfd_perform_relocation' +................................. + +*Synopsis* + bfd_reloc_status_type bfd_perform_relocation + (bfd *abfd, + arelent *reloc_entry, + void *data, + asection *input_section, + bfd *output_bfd, + char **error_message); + *Description* +If OUTPUT_BFD is supplied to this function, the generated image will be +relocatable; the relocations are copied to the output file after they +have been changed to reflect the new state of the world. There are two +ways of reflecting the results of partial linkage in an output file: by +modifying the output data in place, and by modifying the relocation +record. Some native formats (e.g., basic a.out and basic coff) have no +way of specifying an addend in the relocation type, so the addend has +to go in the output data. This is no big deal since in these formats +the output data slot will always be big enough for the addend. Complex +reloc types with addends were invented to solve just this problem. The +ERROR_MESSAGE argument is set to an error message if this return +`bfd_reloc_dangerous'. + +2.10.1.8 `bfd_install_relocation' +................................. + +*Synopsis* + bfd_reloc_status_type bfd_install_relocation + (bfd *abfd, + arelent *reloc_entry, + void *data, bfd_vma data_start, + asection *input_section, + char **error_message); + *Description* +This looks remarkably like `bfd_perform_relocation', except it does not +expect that the section contents have been filled in. I.e., it's +suitable for use when creating, rather than applying a relocation. + + For now, this function should be considered reserved for the +assembler. + + +File: bfd.info, Node: howto manager, Prev: typedef arelent, Up: Relocations + +2.10.2 The howto manager +------------------------ + +When an application wants to create a relocation, but doesn't know what +the target machine might call it, it can find out by using this bit of +code. + +2.10.2.1 `bfd_reloc_code_type' +.............................. + +*Description* +The insides of a reloc code. The idea is that, eventually, there will +be one enumerator for every type of relocation we ever do. Pass one of +these values to `bfd_reloc_type_lookup', and it'll return a howto +pointer. + + This does mean that the application must determine the correct +enumerator value; you can't get a howto pointer from a random set of +attributes. + + Here are the possible values for `enum bfd_reloc_code_real': + + -- : BFD_RELOC_64 + -- : BFD_RELOC_32 + -- : BFD_RELOC_26 + -- : BFD_RELOC_24 + -- : BFD_RELOC_16 + -- : BFD_RELOC_14 + -- : BFD_RELOC_8 + Basic absolute relocations of N bits. + + -- : BFD_RELOC_64_PCREL + -- : BFD_RELOC_32_PCREL + -- : BFD_RELOC_24_PCREL + -- : BFD_RELOC_16_PCREL + -- : BFD_RELOC_12_PCREL + -- : BFD_RELOC_8_PCREL + PC-relative relocations. Sometimes these are relative to the + address of the relocation itself; sometimes they are relative to + the start of the section containing the relocation. It depends on + the specific target. + + The 24-bit relocation is used in some Intel 960 configurations. + + -- : BFD_RELOC_32_SECREL + Section relative relocations. Some targets need this for DWARF2. + + -- : BFD_RELOC_32_GOT_PCREL + -- : BFD_RELOC_16_GOT_PCREL + -- : BFD_RELOC_8_GOT_PCREL + -- : BFD_RELOC_32_GOTOFF + -- : BFD_RELOC_16_GOTOFF + -- : BFD_RELOC_LO16_GOTOFF + -- : BFD_RELOC_HI16_GOTOFF + -- : BFD_RELOC_HI16_S_GOTOFF + -- : BFD_RELOC_8_GOTOFF + -- : BFD_RELOC_64_PLT_PCREL + -- : BFD_RELOC_32_PLT_PCREL + -- : BFD_RELOC_24_PLT_PCREL + -- : BFD_RELOC_16_PLT_PCREL + -- : BFD_RELOC_8_PLT_PCREL + -- : BFD_RELOC_64_PLTOFF + -- : BFD_RELOC_32_PLTOFF + -- : BFD_RELOC_16_PLTOFF + -- : BFD_RELOC_LO16_PLTOFF + -- : BFD_RELOC_HI16_PLTOFF + -- : BFD_RELOC_HI16_S_PLTOFF + -- : BFD_RELOC_8_PLTOFF + For ELF. + + -- : BFD_RELOC_68K_GLOB_DAT + -- : BFD_RELOC_68K_JMP_SLOT + -- : BFD_RELOC_68K_RELATIVE + -- : BFD_RELOC_68K_TLS_GD32 + -- : BFD_RELOC_68K_TLS_GD16 + -- : BFD_RELOC_68K_TLS_GD8 + -- : BFD_RELOC_68K_TLS_LDM32 + -- : BFD_RELOC_68K_TLS_LDM16 + -- : BFD_RELOC_68K_TLS_LDM8 + -- : BFD_RELOC_68K_TLS_LDO32 + -- : BFD_RELOC_68K_TLS_LDO16 + -- : BFD_RELOC_68K_TLS_LDO8 + -- : BFD_RELOC_68K_TLS_IE32 + -- : BFD_RELOC_68K_TLS_IE16 + -- : BFD_RELOC_68K_TLS_IE8 + -- : BFD_RELOC_68K_TLS_LE32 + -- : BFD_RELOC_68K_TLS_LE16 + -- : BFD_RELOC_68K_TLS_LE8 + Relocations used by 68K ELF. + + -- : BFD_RELOC_32_BASEREL + -- : BFD_RELOC_16_BASEREL + -- : BFD_RELOC_LO16_BASEREL + -- : BFD_RELOC_HI16_BASEREL + -- : BFD_RELOC_HI16_S_BASEREL + -- : BFD_RELOC_8_BASEREL + -- : BFD_RELOC_RVA + Linkage-table relative. + + -- : BFD_RELOC_8_FFnn + Absolute 8-bit relocation, but used to form an address like 0xFFnn. + + -- : BFD_RELOC_32_PCREL_S2 + -- : BFD_RELOC_16_PCREL_S2 + -- : BFD_RELOC_23_PCREL_S2 + These PC-relative relocations are stored as word displacements - + i.e., byte displacements shifted right two bits. The 30-bit word + displacement (<<32_PCREL_S2>> - 32 bits, shifted 2) is used on the + SPARC. (SPARC tools generally refer to this as <<WDISP30>>.) The + signed 16-bit displacement is used on the MIPS, and the 23-bit + displacement is used on the Alpha. + + -- : BFD_RELOC_HI22 + -- : BFD_RELOC_LO10 + High 22 bits and low 10 bits of 32-bit value, placed into lower + bits of the target word. These are used on the SPARC. + + -- : BFD_RELOC_GPREL16 + -- : BFD_RELOC_GPREL32 + For systems that allocate a Global Pointer register, these are + displacements off that register. These relocation types are + handled specially, because the value the register will have is + decided relatively late. + + -- : BFD_RELOC_I960_CALLJ + Reloc types used for i960/b.out. + + -- : BFD_RELOC_NONE + -- : BFD_RELOC_SPARC_WDISP22 + -- : BFD_RELOC_SPARC22 + -- : BFD_RELOC_SPARC13 + -- : BFD_RELOC_SPARC_GOT10 + -- : BFD_RELOC_SPARC_GOT13 + -- : BFD_RELOC_SPARC_GOT22 + -- : BFD_RELOC_SPARC_PC10 + -- : BFD_RELOC_SPARC_PC22 + -- : BFD_RELOC_SPARC_WPLT30 + -- : BFD_RELOC_SPARC_COPY + -- : BFD_RELOC_SPARC_GLOB_DAT + -- : BFD_RELOC_SPARC_JMP_SLOT + -- : BFD_RELOC_SPARC_RELATIVE + -- : BFD_RELOC_SPARC_UA16 + -- : BFD_RELOC_SPARC_UA32 + -- : BFD_RELOC_SPARC_UA64 + -- : BFD_RELOC_SPARC_GOTDATA_HIX22 + -- : BFD_RELOC_SPARC_GOTDATA_LOX10 + -- : BFD_RELOC_SPARC_GOTDATA_OP_HIX22 + -- : BFD_RELOC_SPARC_GOTDATA_OP_LOX10 + -- : BFD_RELOC_SPARC_GOTDATA_OP + SPARC ELF relocations. There is probably some overlap with other + relocation types already defined. + + -- : BFD_RELOC_SPARC_BASE13 + -- : BFD_RELOC_SPARC_BASE22 + I think these are specific to SPARC a.out (e.g., Sun 4). + + -- : BFD_RELOC_SPARC_64 + -- : BFD_RELOC_SPARC_10 + -- : BFD_RELOC_SPARC_11 + -- : BFD_RELOC_SPARC_OLO10 + -- : BFD_RELOC_SPARC_HH22 + -- : BFD_RELOC_SPARC_HM10 + -- : BFD_RELOC_SPARC_LM22 + -- : BFD_RELOC_SPARC_PC_HH22 + -- : BFD_RELOC_SPARC_PC_HM10 + -- : BFD_RELOC_SPARC_PC_LM22 + -- : BFD_RELOC_SPARC_WDISP16 + -- : BFD_RELOC_SPARC_WDISP19 + -- : BFD_RELOC_SPARC_7 + -- : BFD_RELOC_SPARC_6 + -- : BFD_RELOC_SPARC_5 + -- : BFD_RELOC_SPARC_DISP64 + -- : BFD_RELOC_SPARC_PLT32 + -- : BFD_RELOC_SPARC_PLT64 + -- : BFD_RELOC_SPARC_HIX22 + -- : BFD_RELOC_SPARC_LOX10 + -- : BFD_RELOC_SPARC_H44 + -- : BFD_RELOC_SPARC_M44 + -- : BFD_RELOC_SPARC_L44 + -- : BFD_RELOC_SPARC_REGISTER + SPARC64 relocations + + -- : BFD_RELOC_SPARC_REV32 + SPARC little endian relocation + + -- : BFD_RELOC_SPARC_TLS_GD_HI22 + -- : BFD_RELOC_SPARC_TLS_GD_LO10 + -- : BFD_RELOC_SPARC_TLS_GD_ADD + -- : BFD_RELOC_SPARC_TLS_GD_CALL + -- : BFD_RELOC_SPARC_TLS_LDM_HI22 + -- : BFD_RELOC_SPARC_TLS_LDM_LO10 + -- : BFD_RELOC_SPARC_TLS_LDM_ADD + -- : BFD_RELOC_SPARC_TLS_LDM_CALL + -- : BFD_RELOC_SPARC_TLS_LDO_HIX22 + -- : BFD_RELOC_SPARC_TLS_LDO_LOX10 + -- : BFD_RELOC_SPARC_TLS_LDO_ADD + -- : BFD_RELOC_SPARC_TLS_IE_HI22 + -- : BFD_RELOC_SPARC_TLS_IE_LO10 + -- : BFD_RELOC_SPARC_TLS_IE_LD + -- : BFD_RELOC_SPARC_TLS_IE_LDX + -- : BFD_RELOC_SPARC_TLS_IE_ADD + -- : BFD_RELOC_SPARC_TLS_LE_HIX22 + -- : BFD_RELOC_SPARC_TLS_LE_LOX10 + -- : BFD_RELOC_SPARC_TLS_DTPMOD32 + -- : BFD_RELOC_SPARC_TLS_DTPMOD64 + -- : BFD_RELOC_SPARC_TLS_DTPOFF32 + -- : BFD_RELOC_SPARC_TLS_DTPOFF64 + -- : BFD_RELOC_SPARC_TLS_TPOFF32 + -- : BFD_RELOC_SPARC_TLS_TPOFF64 + SPARC TLS relocations + + -- : BFD_RELOC_SPU_IMM7 + -- : BFD_RELOC_SPU_IMM8 + -- : BFD_RELOC_SPU_IMM10 + -- : BFD_RELOC_SPU_IMM10W + -- : BFD_RELOC_SPU_IMM16 + -- : BFD_RELOC_SPU_IMM16W + -- : BFD_RELOC_SPU_IMM18 + -- : BFD_RELOC_SPU_PCREL9a + -- : BFD_RELOC_SPU_PCREL9b + -- : BFD_RELOC_SPU_PCREL16 + -- : BFD_RELOC_SPU_LO16 + -- : BFD_RELOC_SPU_HI16 + -- : BFD_RELOC_SPU_PPU32 + -- : BFD_RELOC_SPU_PPU64 + -- : BFD_RELOC_SPU_ADD_PIC + SPU Relocations. + + -- : BFD_RELOC_ALPHA_GPDISP_HI16 + Alpha ECOFF and ELF relocations. Some of these treat the symbol or + "addend" in some special way. For GPDISP_HI16 ("gpdisp") + relocations, the symbol is ignored when writing; when reading, it + will be the absolute section symbol. The addend is the + displacement in bytes of the "lda" instruction from the "ldah" + instruction (which is at the address of this reloc). + + -- : BFD_RELOC_ALPHA_GPDISP_LO16 + For GPDISP_LO16 ("ignore") relocations, the symbol is handled as + with GPDISP_HI16 relocs. The addend is ignored when writing the + relocations out, and is filled in with the file's GP value on + reading, for convenience. + + -- : BFD_RELOC_ALPHA_GPDISP + The ELF GPDISP relocation is exactly the same as the GPDISP_HI16 + relocation except that there is no accompanying GPDISP_LO16 + relocation. + + -- : BFD_RELOC_ALPHA_LITERAL + -- : BFD_RELOC_ALPHA_ELF_LITERAL + -- : BFD_RELOC_ALPHA_LITUSE + The Alpha LITERAL/LITUSE relocs are produced by a symbol reference; + the assembler turns it into a LDQ instruction to load the address + of the symbol, and then fills in a register in the real + instruction. + + The LITERAL reloc, at the LDQ instruction, refers to the .lita + section symbol. The addend is ignored when writing, but is filled + in with the file's GP value on reading, for convenience, as with + the GPDISP_LO16 reloc. + + The ELF_LITERAL reloc is somewhere between 16_GOTOFF and + GPDISP_LO16. It should refer to the symbol to be referenced, as + with 16_GOTOFF, but it generates output not based on the position + within the .got section, but relative to the GP value chosen for + the file during the final link stage. + + The LITUSE reloc, on the instruction using the loaded address, + gives information to the linker that it might be able to use to + optimize away some literal section references. The symbol is + ignored (read as the absolute section symbol), and the "addend" + indicates the type of instruction using the register: 1 - "memory" + fmt insn 2 - byte-manipulation (byte offset reg) 3 - jsr (target + of branch) + + -- : BFD_RELOC_ALPHA_HINT + The HINT relocation indicates a value that should be filled into + the "hint" field of a jmp/jsr/ret instruction, for possible branch- + prediction logic which may be provided on some processors. + + -- : BFD_RELOC_ALPHA_LINKAGE + The LINKAGE relocation outputs a linkage pair in the object file, + which is filled by the linker. + + -- : BFD_RELOC_ALPHA_CODEADDR + The CODEADDR relocation outputs a STO_CA in the object file, which + is filled by the linker. + + -- : BFD_RELOC_ALPHA_GPREL_HI16 + -- : BFD_RELOC_ALPHA_GPREL_LO16 + The GPREL_HI/LO relocations together form a 32-bit offset from the + GP register. + + -- : BFD_RELOC_ALPHA_BRSGP + Like BFD_RELOC_23_PCREL_S2, except that the source and target must + share a common GP, and the target address is adjusted for + STO_ALPHA_STD_GPLOAD. + + -- : BFD_RELOC_ALPHA_NOP + The NOP relocation outputs a NOP if the longword displacement + between two procedure entry points is < 2^21. + + -- : BFD_RELOC_ALPHA_BSR + The BSR relocation outputs a BSR if the longword displacement + between two procedure entry points is < 2^21. + + -- : BFD_RELOC_ALPHA_LDA + The LDA relocation outputs a LDA if the longword displacement + between two procedure entry points is < 2^16. + + -- : BFD_RELOC_ALPHA_BOH + The BOH relocation outputs a BSR if the longword displacement + between two procedure entry points is < 2^21, or else a hint. + + -- : BFD_RELOC_ALPHA_TLSGD + -- : BFD_RELOC_ALPHA_TLSLDM + -- : BFD_RELOC_ALPHA_DTPMOD64 + -- : BFD_RELOC_ALPHA_GOTDTPREL16 + -- : BFD_RELOC_ALPHA_DTPREL64 + -- : BFD_RELOC_ALPHA_DTPREL_HI16 + -- : BFD_RELOC_ALPHA_DTPREL_LO16 + -- : BFD_RELOC_ALPHA_DTPREL16 + -- : BFD_RELOC_ALPHA_GOTTPREL16 + -- : BFD_RELOC_ALPHA_TPREL64 + -- : BFD_RELOC_ALPHA_TPREL_HI16 + -- : BFD_RELOC_ALPHA_TPREL_LO16 + -- : BFD_RELOC_ALPHA_TPREL16 + Alpha thread-local storage relocations. + + -- : BFD_RELOC_MIPS_JMP + Bits 27..2 of the relocation address shifted right 2 bits; simple + reloc otherwise. + + -- : BFD_RELOC_MIPS16_JMP + The MIPS16 jump instruction. + + -- : BFD_RELOC_MIPS16_GPREL + MIPS16 GP relative reloc. + + -- : BFD_RELOC_HI16 + High 16 bits of 32-bit value; simple reloc. + + -- : BFD_RELOC_HI16_S + High 16 bits of 32-bit value but the low 16 bits will be sign + extended and added to form the final result. If the low 16 bits + form a negative number, we need to add one to the high value to + compensate for the borrow when the low bits are added. + + -- : BFD_RELOC_LO16 + Low 16 bits. + + -- : BFD_RELOC_HI16_PCREL + High 16 bits of 32-bit pc-relative value + + -- : BFD_RELOC_HI16_S_PCREL + High 16 bits of 32-bit pc-relative value, adjusted + + -- : BFD_RELOC_LO16_PCREL + Low 16 bits of pc-relative value + + -- : BFD_RELOC_MIPS16_GOT16 + -- : BFD_RELOC_MIPS16_CALL16 + Equivalent of BFD_RELOC_MIPS_*, but with the MIPS16 layout of + 16-bit immediate fields + + -- : BFD_RELOC_MIPS16_HI16 + MIPS16 high 16 bits of 32-bit value. + + -- : BFD_RELOC_MIPS16_HI16_S + MIPS16 high 16 bits of 32-bit value but the low 16 bits will be + sign extended and added to form the final result. If the low 16 + bits form a negative number, we need to add one to the high value + to compensate for the borrow when the low bits are added. + + -- : BFD_RELOC_MIPS16_LO16 + MIPS16 low 16 bits. + + -- : BFD_RELOC_MIPS_LITERAL + Relocation against a MIPS literal section. + + -- : BFD_RELOC_MIPS_GOT16 + -- : BFD_RELOC_MIPS_CALL16 + -- : BFD_RELOC_MIPS_GOT_HI16 + -- : BFD_RELOC_MIPS_GOT_LO16 + -- : BFD_RELOC_MIPS_CALL_HI16 + -- : BFD_RELOC_MIPS_CALL_LO16 + -- : BFD_RELOC_MIPS_SUB + -- : BFD_RELOC_MIPS_GOT_PAGE + -- : BFD_RELOC_MIPS_GOT_OFST + -- : BFD_RELOC_MIPS_GOT_DISP + -- : BFD_RELOC_MIPS_SHIFT5 + -- : BFD_RELOC_MIPS_SHIFT6 + -- : BFD_RELOC_MIPS_INSERT_A + -- : BFD_RELOC_MIPS_INSERT_B + -- : BFD_RELOC_MIPS_DELETE + -- : BFD_RELOC_MIPS_HIGHEST + -- : BFD_RELOC_MIPS_HIGHER + -- : BFD_RELOC_MIPS_SCN_DISP + -- : BFD_RELOC_MIPS_REL16 + -- : BFD_RELOC_MIPS_RELGOT + -- : BFD_RELOC_MIPS_JALR + -- : BFD_RELOC_MIPS_TLS_DTPMOD32 + -- : BFD_RELOC_MIPS_TLS_DTPREL32 + -- : BFD_RELOC_MIPS_TLS_DTPMOD64 + -- : BFD_RELOC_MIPS_TLS_DTPREL64 + -- : BFD_RELOC_MIPS_TLS_GD + -- : BFD_RELOC_MIPS_TLS_LDM + -- : BFD_RELOC_MIPS_TLS_DTPREL_HI16 + -- : BFD_RELOC_MIPS_TLS_DTPREL_LO16 + -- : BFD_RELOC_MIPS_TLS_GOTTPREL + -- : BFD_RELOC_MIPS_TLS_TPREL32 + -- : BFD_RELOC_MIPS_TLS_TPREL64 + -- : BFD_RELOC_MIPS_TLS_TPREL_HI16 + -- : BFD_RELOC_MIPS_TLS_TPREL_LO16 + MIPS ELF relocations. + + -- : BFD_RELOC_MIPS_COPY + -- : BFD_RELOC_MIPS_JUMP_SLOT + MIPS ELF relocations (VxWorks and PLT extensions). + + -- : BFD_RELOC_MOXIE_10_PCREL + Moxie ELF relocations. + + -- : BFD_RELOC_FRV_LABEL16 + -- : BFD_RELOC_FRV_LABEL24 + -- : BFD_RELOC_FRV_LO16 + -- : BFD_RELOC_FRV_HI16 + -- : BFD_RELOC_FRV_GPREL12 + -- : BFD_RELOC_FRV_GPRELU12 + -- : BFD_RELOC_FRV_GPREL32 + -- : BFD_RELOC_FRV_GPRELHI + -- : BFD_RELOC_FRV_GPRELLO + -- : BFD_RELOC_FRV_GOT12 + -- : BFD_RELOC_FRV_GOTHI + -- : BFD_RELOC_FRV_GOTLO + -- : BFD_RELOC_FRV_FUNCDESC + -- : BFD_RELOC_FRV_FUNCDESC_GOT12 + -- : BFD_RELOC_FRV_FUNCDESC_GOTHI + -- : BFD_RELOC_FRV_FUNCDESC_GOTLO + -- : BFD_RELOC_FRV_FUNCDESC_VALUE + -- : BFD_RELOC_FRV_FUNCDESC_GOTOFF12 + -- : BFD_RELOC_FRV_FUNCDESC_GOTOFFHI + -- : BFD_RELOC_FRV_FUNCDESC_GOTOFFLO + -- : BFD_RELOC_FRV_GOTOFF12 + -- : BFD_RELOC_FRV_GOTOFFHI + -- : BFD_RELOC_FRV_GOTOFFLO + -- : BFD_RELOC_FRV_GETTLSOFF + -- : BFD_RELOC_FRV_TLSDESC_VALUE + -- : BFD_RELOC_FRV_GOTTLSDESC12 + -- : BFD_RELOC_FRV_GOTTLSDESCHI + -- : BFD_RELOC_FRV_GOTTLSDESCLO + -- : BFD_RELOC_FRV_TLSMOFF12 + -- : BFD_RELOC_FRV_TLSMOFFHI + -- : BFD_RELOC_FRV_TLSMOFFLO + -- : BFD_RELOC_FRV_GOTTLSOFF12 + -- : BFD_RELOC_FRV_GOTTLSOFFHI + -- : BFD_RELOC_FRV_GOTTLSOFFLO + -- : BFD_RELOC_FRV_TLSOFF + -- : BFD_RELOC_FRV_TLSDESC_RELAX + -- : BFD_RELOC_FRV_GETTLSOFF_RELAX + -- : BFD_RELOC_FRV_TLSOFF_RELAX + -- : BFD_RELOC_FRV_TLSMOFF + Fujitsu Frv Relocations. + + -- : BFD_RELOC_MN10300_GOTOFF24 + This is a 24bit GOT-relative reloc for the mn10300. + + -- : BFD_RELOC_MN10300_GOT32 + This is a 32bit GOT-relative reloc for the mn10300, offset by two + bytes in the instruction. + + -- : BFD_RELOC_MN10300_GOT24 + This is a 24bit GOT-relative reloc for the mn10300, offset by two + bytes in the instruction. + + -- : BFD_RELOC_MN10300_GOT16 + This is a 16bit GOT-relative reloc for the mn10300, offset by two + bytes in the instruction. + + -- : BFD_RELOC_MN10300_COPY + Copy symbol at runtime. + + -- : BFD_RELOC_MN10300_GLOB_DAT + Create GOT entry. + + -- : BFD_RELOC_MN10300_JMP_SLOT + Create PLT entry. + + -- : BFD_RELOC_MN10300_RELATIVE + Adjust by program base. + + -- : BFD_RELOC_MN10300_SYM_DIFF + Together with another reloc targeted at the same location, allows + for a value that is the difference of two symbols in the same + section. + + -- : BFD_RELOC_MN10300_ALIGN + The addend of this reloc is an alignment power that must be + honoured at the offset's location, regardless of linker relaxation. + + -- : BFD_RELOC_386_GOT32 + -- : BFD_RELOC_386_PLT32 + -- : BFD_RELOC_386_COPY + -- : BFD_RELOC_386_GLOB_DAT + -- : BFD_RELOC_386_JUMP_SLOT + -- : BFD_RELOC_386_RELATIVE + -- : BFD_RELOC_386_GOTOFF + -- : BFD_RELOC_386_GOTPC + -- : BFD_RELOC_386_TLS_TPOFF + -- : BFD_RELOC_386_TLS_IE + -- : BFD_RELOC_386_TLS_GOTIE + -- : BFD_RELOC_386_TLS_LE + -- : BFD_RELOC_386_TLS_GD + -- : BFD_RELOC_386_TLS_LDM + -- : BFD_RELOC_386_TLS_LDO_32 + -- : BFD_RELOC_386_TLS_IE_32 + -- : BFD_RELOC_386_TLS_LE_32 + -- : BFD_RELOC_386_TLS_DTPMOD32 + -- : BFD_RELOC_386_TLS_DTPOFF32 + -- : BFD_RELOC_386_TLS_TPOFF32 + -- : BFD_RELOC_386_TLS_GOTDESC + -- : BFD_RELOC_386_TLS_DESC_CALL + -- : BFD_RELOC_386_TLS_DESC + -- : BFD_RELOC_386_IRELATIVE + i386/elf relocations + + -- : BFD_RELOC_X86_64_GOT32 + -- : BFD_RELOC_X86_64_PLT32 + -- : BFD_RELOC_X86_64_COPY + -- : BFD_RELOC_X86_64_GLOB_DAT + -- : BFD_RELOC_X86_64_JUMP_SLOT + -- : BFD_RELOC_X86_64_RELATIVE + -- : BFD_RELOC_X86_64_GOTPCREL + -- : BFD_RELOC_X86_64_32S + -- : BFD_RELOC_X86_64_DTPMOD64 + -- : BFD_RELOC_X86_64_DTPOFF64 + -- : BFD_RELOC_X86_64_TPOFF64 + -- : BFD_RELOC_X86_64_TLSGD + -- : BFD_RELOC_X86_64_TLSLD + -- : BFD_RELOC_X86_64_DTPOFF32 + -- : BFD_RELOC_X86_64_GOTTPOFF + -- : BFD_RELOC_X86_64_TPOFF32 + -- : BFD_RELOC_X86_64_GOTOFF64 + -- : BFD_RELOC_X86_64_GOTPC32 + -- : BFD_RELOC_X86_64_GOT64 + -- : BFD_RELOC_X86_64_GOTPCREL64 + -- : BFD_RELOC_X86_64_GOTPC64 + -- : BFD_RELOC_X86_64_GOTPLT64 + -- : BFD_RELOC_X86_64_PLTOFF64 + -- : BFD_RELOC_X86_64_GOTPC32_TLSDESC + -- : BFD_RELOC_X86_64_TLSDESC_CALL + -- : BFD_RELOC_X86_64_TLSDESC + -- : BFD_RELOC_X86_64_IRELATIVE + x86-64/elf relocations + + -- : BFD_RELOC_NS32K_IMM_8 + -- : BFD_RELOC_NS32K_IMM_16 + -- : BFD_RELOC_NS32K_IMM_32 + -- : BFD_RELOC_NS32K_IMM_8_PCREL + -- : BFD_RELOC_NS32K_IMM_16_PCREL + -- : BFD_RELOC_NS32K_IMM_32_PCREL + -- : BFD_RELOC_NS32K_DISP_8 + -- : BFD_RELOC_NS32K_DISP_16 + -- : BFD_RELOC_NS32K_DISP_32 + -- : BFD_RELOC_NS32K_DISP_8_PCREL + -- : BFD_RELOC_NS32K_DISP_16_PCREL + -- : BFD_RELOC_NS32K_DISP_32_PCREL + ns32k relocations + + -- : BFD_RELOC_PDP11_DISP_8_PCREL + -- : BFD_RELOC_PDP11_DISP_6_PCREL + PDP11 relocations + + -- : BFD_RELOC_PJ_CODE_HI16 + -- : BFD_RELOC_PJ_CODE_LO16 + -- : BFD_RELOC_PJ_CODE_DIR16 + -- : BFD_RELOC_PJ_CODE_DIR32 + -- : BFD_RELOC_PJ_CODE_REL16 + -- : BFD_RELOC_PJ_CODE_REL32 + Picojava relocs. Not all of these appear in object files. + + -- : BFD_RELOC_PPC_B26 + -- : BFD_RELOC_PPC_BA26 + -- : BFD_RELOC_PPC_TOC16 + -- : BFD_RELOC_PPC_B16 + -- : BFD_RELOC_PPC_B16_BRTAKEN + -- : BFD_RELOC_PPC_B16_BRNTAKEN + -- : BFD_RELOC_PPC_BA16 + -- : BFD_RELOC_PPC_BA16_BRTAKEN + -- : BFD_RELOC_PPC_BA16_BRNTAKEN + -- : BFD_RELOC_PPC_COPY + -- : BFD_RELOC_PPC_GLOB_DAT + -- : BFD_RELOC_PPC_JMP_SLOT + -- : BFD_RELOC_PPC_RELATIVE + -- : BFD_RELOC_PPC_LOCAL24PC + -- : BFD_RELOC_PPC_EMB_NADDR32 + -- : BFD_RELOC_PPC_EMB_NADDR16 + -- : BFD_RELOC_PPC_EMB_NADDR16_LO + -- : BFD_RELOC_PPC_EMB_NADDR16_HI + -- : BFD_RELOC_PPC_EMB_NADDR16_HA + -- : BFD_RELOC_PPC_EMB_SDAI16 + -- : BFD_RELOC_PPC_EMB_SDA2I16 + -- : BFD_RELOC_PPC_EMB_SDA2REL + -- : BFD_RELOC_PPC_EMB_SDA21 + -- : BFD_RELOC_PPC_EMB_MRKREF + -- : BFD_RELOC_PPC_EMB_RELSEC16 + -- : BFD_RELOC_PPC_EMB_RELST_LO + -- : BFD_RELOC_PPC_EMB_RELST_HI + -- : BFD_RELOC_PPC_EMB_RELST_HA + -- : BFD_RELOC_PPC_EMB_BIT_FLD + -- : BFD_RELOC_PPC_EMB_RELSDA + -- : BFD_RELOC_PPC64_HIGHER + -- : BFD_RELOC_PPC64_HIGHER_S + -- : BFD_RELOC_PPC64_HIGHEST + -- : BFD_RELOC_PPC64_HIGHEST_S + -- : BFD_RELOC_PPC64_TOC16_LO + -- : BFD_RELOC_PPC64_TOC16_HI + -- : BFD_RELOC_PPC64_TOC16_HA + -- : BFD_RELOC_PPC64_TOC + -- : BFD_RELOC_PPC64_PLTGOT16 + -- : BFD_RELOC_PPC64_PLTGOT16_LO + -- : BFD_RELOC_PPC64_PLTGOT16_HI + -- : BFD_RELOC_PPC64_PLTGOT16_HA + -- : BFD_RELOC_PPC64_ADDR16_DS + -- : BFD_RELOC_PPC64_ADDR16_LO_DS + -- : BFD_RELOC_PPC64_GOT16_DS + -- : BFD_RELOC_PPC64_GOT16_LO_DS + -- : BFD_RELOC_PPC64_PLT16_LO_DS + -- : BFD_RELOC_PPC64_SECTOFF_DS + -- : BFD_RELOC_PPC64_SECTOFF_LO_DS + -- : BFD_RELOC_PPC64_TOC16_DS + -- : BFD_RELOC_PPC64_TOC16_LO_DS + -- : BFD_RELOC_PPC64_PLTGOT16_DS + -- : BFD_RELOC_PPC64_PLTGOT16_LO_DS + Power(rs6000) and PowerPC relocations. + + -- : BFD_RELOC_PPC_TLS + -- : BFD_RELOC_PPC_TLSGD + -- : BFD_RELOC_PPC_TLSLD + -- : BFD_RELOC_PPC_DTPMOD + -- : BFD_RELOC_PPC_TPREL16 + -- : BFD_RELOC_PPC_TPREL16_LO + -- : BFD_RELOC_PPC_TPREL16_HI + -- : BFD_RELOC_PPC_TPREL16_HA + -- : BFD_RELOC_PPC_TPREL + -- : BFD_RELOC_PPC_DTPREL16 + -- : BFD_RELOC_PPC_DTPREL16_LO + -- : BFD_RELOC_PPC_DTPREL16_HI + -- : BFD_RELOC_PPC_DTPREL16_HA + -- : BFD_RELOC_PPC_DTPREL + -- : BFD_RELOC_PPC_GOT_TLSGD16 + -- : BFD_RELOC_PPC_GOT_TLSGD16_LO + -- : BFD_RELOC_PPC_GOT_TLSGD16_HI + -- : BFD_RELOC_PPC_GOT_TLSGD16_HA + -- : BFD_RELOC_PPC_GOT_TLSLD16 + -- : BFD_RELOC_PPC_GOT_TLSLD16_LO + -- : BFD_RELOC_PPC_GOT_TLSLD16_HI + -- : BFD_RELOC_PPC_GOT_TLSLD16_HA + -- : BFD_RELOC_PPC_GOT_TPREL16 + -- : BFD_RELOC_PPC_GOT_TPREL16_LO + -- : BFD_RELOC_PPC_GOT_TPREL16_HI + -- : BFD_RELOC_PPC_GOT_TPREL16_HA + -- : BFD_RELOC_PPC_GOT_DTPREL16 + -- : BFD_RELOC_PPC_GOT_DTPREL16_LO + -- : BFD_RELOC_PPC_GOT_DTPREL16_HI + -- : BFD_RELOC_PPC_GOT_DTPREL16_HA + -- : BFD_RELOC_PPC64_TPREL16_DS + -- : BFD_RELOC_PPC64_TPREL16_LO_DS + -- : BFD_RELOC_PPC64_TPREL16_HIGHER + -- : BFD_RELOC_PPC64_TPREL16_HIGHERA + -- : BFD_RELOC_PPC64_TPREL16_HIGHEST + -- : BFD_RELOC_PPC64_TPREL16_HIGHESTA + -- : BFD_RELOC_PPC64_DTPREL16_DS + -- : BFD_RELOC_PPC64_DTPREL16_LO_DS + -- : BFD_RELOC_PPC64_DTPREL16_HIGHER + -- : BFD_RELOC_PPC64_DTPREL16_HIGHERA + -- : BFD_RELOC_PPC64_DTPREL16_HIGHEST + -- : BFD_RELOC_PPC64_DTPREL16_HIGHESTA + PowerPC and PowerPC64 thread-local storage relocations. + + -- : BFD_RELOC_I370_D12 + IBM 370/390 relocations + + -- : BFD_RELOC_CTOR + The type of reloc used to build a constructor table - at the moment + probably a 32 bit wide absolute relocation, but the target can + choose. It generally does map to one of the other relocation + types. + + -- : BFD_RELOC_ARM_PCREL_BRANCH + ARM 26 bit pc-relative branch. The lowest two bits must be zero + and are not stored in the instruction. + + -- : BFD_RELOC_ARM_PCREL_BLX + ARM 26 bit pc-relative branch. The lowest bit must be zero and is + not stored in the instruction. The 2nd lowest bit comes from a 1 + bit field in the instruction. + + -- : BFD_RELOC_THUMB_PCREL_BLX + Thumb 22 bit pc-relative branch. The lowest bit must be zero and + is not stored in the instruction. The 2nd lowest bit comes from a + 1 bit field in the instruction. + + -- : BFD_RELOC_ARM_PCREL_CALL + ARM 26-bit pc-relative branch for an unconditional BL or BLX + instruction. + + -- : BFD_RELOC_ARM_PCREL_JUMP + ARM 26-bit pc-relative branch for B or conditional BL instruction. + + -- : BFD_RELOC_THUMB_PCREL_BRANCH7 + -- : BFD_RELOC_THUMB_PCREL_BRANCH9 + -- : BFD_RELOC_THUMB_PCREL_BRANCH12 + -- : BFD_RELOC_THUMB_PCREL_BRANCH20 + -- : BFD_RELOC_THUMB_PCREL_BRANCH23 + -- : BFD_RELOC_THUMB_PCREL_BRANCH25 + Thumb 7-, 9-, 12-, 20-, 23-, and 25-bit pc-relative branches. The + lowest bit must be zero and is not stored in the instruction. + Note that the corresponding ELF R_ARM_THM_JUMPnn constant has an + "nn" one smaller in all cases. Note further that BRANCH23 + corresponds to R_ARM_THM_CALL. + + -- : BFD_RELOC_ARM_OFFSET_IMM + 12-bit immediate offset, used in ARM-format ldr and str + instructions. + + -- : BFD_RELOC_ARM_THUMB_OFFSET + 5-bit immediate offset, used in Thumb-format ldr and str + instructions. + + -- : BFD_RELOC_ARM_TARGET1 + Pc-relative or absolute relocation depending on target. Used for + entries in .init_array sections. + + -- : BFD_RELOC_ARM_ROSEGREL32 + Read-only segment base relative address. + + -- : BFD_RELOC_ARM_SBREL32 + Data segment base relative address. + + -- : BFD_RELOC_ARM_TARGET2 + This reloc is used for references to RTTI data from exception + handling tables. The actual definition depends on the target. It + may be a pc-relative or some form of GOT-indirect relocation. + + -- : BFD_RELOC_ARM_PREL31 + 31-bit PC relative address. + + -- : BFD_RELOC_ARM_MOVW + -- : BFD_RELOC_ARM_MOVT + -- : BFD_RELOC_ARM_MOVW_PCREL + -- : BFD_RELOC_ARM_MOVT_PCREL + -- : BFD_RELOC_ARM_THUMB_MOVW + -- : BFD_RELOC_ARM_THUMB_MOVT + -- : BFD_RELOC_ARM_THUMB_MOVW_PCREL + -- : BFD_RELOC_ARM_THUMB_MOVT_PCREL + Low and High halfword relocations for MOVW and MOVT instructions. + + -- : BFD_RELOC_ARM_JUMP_SLOT + -- : BFD_RELOC_ARM_GLOB_DAT + -- : BFD_RELOC_ARM_GOT32 + -- : BFD_RELOC_ARM_PLT32 + -- : BFD_RELOC_ARM_RELATIVE + -- : BFD_RELOC_ARM_GOTOFF + -- : BFD_RELOC_ARM_GOTPC + Relocations for setting up GOTs and PLTs for shared libraries. + + -- : BFD_RELOC_ARM_TLS_GD32 + -- : BFD_RELOC_ARM_TLS_LDO32 + -- : BFD_RELOC_ARM_TLS_LDM32 + -- : BFD_RELOC_ARM_TLS_DTPOFF32 + -- : BFD_RELOC_ARM_TLS_DTPMOD32 + -- : BFD_RELOC_ARM_TLS_TPOFF32 + -- : BFD_RELOC_ARM_TLS_IE32 + -- : BFD_RELOC_ARM_TLS_LE32 + ARM thread-local storage relocations. + + -- : BFD_RELOC_ARM_ALU_PC_G0_NC + -- : BFD_RELOC_ARM_ALU_PC_G0 + -- : BFD_RELOC_ARM_ALU_PC_G1_NC + -- : BFD_RELOC_ARM_ALU_PC_G1 + -- : BFD_RELOC_ARM_ALU_PC_G2 + -- : BFD_RELOC_ARM_LDR_PC_G0 + -- : BFD_RELOC_ARM_LDR_PC_G1 + -- : BFD_RELOC_ARM_LDR_PC_G2 + -- : BFD_RELOC_ARM_LDRS_PC_G0 + -- : BFD_RELOC_ARM_LDRS_PC_G1 + -- : BFD_RELOC_ARM_LDRS_PC_G2 + -- : BFD_RELOC_ARM_LDC_PC_G0 + -- : BFD_RELOC_ARM_LDC_PC_G1 + -- : BFD_RELOC_ARM_LDC_PC_G2 + -- : BFD_RELOC_ARM_ALU_SB_G0_NC + -- : BFD_RELOC_ARM_ALU_SB_G0 + -- : BFD_RELOC_ARM_ALU_SB_G1_NC + -- : BFD_RELOC_ARM_ALU_SB_G1 + -- : BFD_RELOC_ARM_ALU_SB_G2 + -- : BFD_RELOC_ARM_LDR_SB_G0 + -- : BFD_RELOC_ARM_LDR_SB_G1 + -- : BFD_RELOC_ARM_LDR_SB_G2 + -- : BFD_RELOC_ARM_LDRS_SB_G0 + -- : BFD_RELOC_ARM_LDRS_SB_G1 + -- : BFD_RELOC_ARM_LDRS_SB_G2 + -- : BFD_RELOC_ARM_LDC_SB_G0 + -- : BFD_RELOC_ARM_LDC_SB_G1 + -- : BFD_RELOC_ARM_LDC_SB_G2 + ARM group relocations. + + -- : BFD_RELOC_ARM_V4BX + Annotation of BX instructions. + + -- : BFD_RELOC_ARM_IMMEDIATE + -- : BFD_RELOC_ARM_ADRL_IMMEDIATE + -- : BFD_RELOC_ARM_T32_IMMEDIATE + -- : BFD_RELOC_ARM_T32_ADD_IMM + -- : BFD_RELOC_ARM_T32_IMM12 + -- : BFD_RELOC_ARM_T32_ADD_PC12 + -- : BFD_RELOC_ARM_SHIFT_IMM + -- : BFD_RELOC_ARM_SMC + -- : BFD_RELOC_ARM_SWI + -- : BFD_RELOC_ARM_MULTI + -- : BFD_RELOC_ARM_CP_OFF_IMM + -- : BFD_RELOC_ARM_CP_OFF_IMM_S2 + -- : BFD_RELOC_ARM_T32_CP_OFF_IMM + -- : BFD_RELOC_ARM_T32_CP_OFF_IMM_S2 + -- : BFD_RELOC_ARM_ADR_IMM + -- : BFD_RELOC_ARM_LDR_IMM + -- : BFD_RELOC_ARM_LITERAL + -- : BFD_RELOC_ARM_IN_POOL + -- : BFD_RELOC_ARM_OFFSET_IMM8 + -- : BFD_RELOC_ARM_T32_OFFSET_U8 + -- : BFD_RELOC_ARM_T32_OFFSET_IMM + -- : BFD_RELOC_ARM_HWLITERAL + -- : BFD_RELOC_ARM_THUMB_ADD + -- : BFD_RELOC_ARM_THUMB_IMM + -- : BFD_RELOC_ARM_THUMB_SHIFT + These relocs are only used within the ARM assembler. They are not + (at present) written to any object files. + + -- : BFD_RELOC_SH_PCDISP8BY2 + -- : BFD_RELOC_SH_PCDISP12BY2 + -- : BFD_RELOC_SH_IMM3 + -- : BFD_RELOC_SH_IMM3U + -- : BFD_RELOC_SH_DISP12 + -- : BFD_RELOC_SH_DISP12BY2 + -- : BFD_RELOC_SH_DISP12BY4 + -- : BFD_RELOC_SH_DISP12BY8 + -- : BFD_RELOC_SH_DISP20 + -- : BFD_RELOC_SH_DISP20BY8 + -- : BFD_RELOC_SH_IMM4 + -- : BFD_RELOC_SH_IMM4BY2 + -- : BFD_RELOC_SH_IMM4BY4 + -- : BFD_RELOC_SH_IMM8 + -- : BFD_RELOC_SH_IMM8BY2 + -- : BFD_RELOC_SH_IMM8BY4 + -- : BFD_RELOC_SH_PCRELIMM8BY2 + -- : BFD_RELOC_SH_PCRELIMM8BY4 + -- : BFD_RELOC_SH_SWITCH16 + -- : BFD_RELOC_SH_SWITCH32 + -- : BFD_RELOC_SH_USES + -- : BFD_RELOC_SH_COUNT + -- : BFD_RELOC_SH_ALIGN + -- : BFD_RELOC_SH_CODE + -- : BFD_RELOC_SH_DATA + -- : BFD_RELOC_SH_LABEL + -- : BFD_RELOC_SH_LOOP_START + -- : BFD_RELOC_SH_LOOP_END + -- : BFD_RELOC_SH_COPY + -- : BFD_RELOC_SH_GLOB_DAT + -- : BFD_RELOC_SH_JMP_SLOT + -- : BFD_RELOC_SH_RELATIVE + -- : BFD_RELOC_SH_GOTPC + -- : BFD_RELOC_SH_GOT_LOW16 + -- : BFD_RELOC_SH_GOT_MEDLOW16 + -- : BFD_RELOC_SH_GOT_MEDHI16 + -- : BFD_RELOC_SH_GOT_HI16 + -- : BFD_RELOC_SH_GOTPLT_LOW16 + -- : BFD_RELOC_SH_GOTPLT_MEDLOW16 + -- : BFD_RELOC_SH_GOTPLT_MEDHI16 + -- : BFD_RELOC_SH_GOTPLT_HI16 + -- : BFD_RELOC_SH_PLT_LOW16 + -- : BFD_RELOC_SH_PLT_MEDLOW16 + -- : BFD_RELOC_SH_PLT_MEDHI16 + -- : BFD_RELOC_SH_PLT_HI16 + -- : BFD_RELOC_SH_GOTOFF_LOW16 + -- : BFD_RELOC_SH_GOTOFF_MEDLOW16 + -- : BFD_RELOC_SH_GOTOFF_MEDHI16 + -- : BFD_RELOC_SH_GOTOFF_HI16 + -- : BFD_RELOC_SH_GOTPC_LOW16 + -- : BFD_RELOC_SH_GOTPC_MEDLOW16 + -- : BFD_RELOC_SH_GOTPC_MEDHI16 + -- : BFD_RELOC_SH_GOTPC_HI16 + -- : BFD_RELOC_SH_COPY64 + -- : BFD_RELOC_SH_GLOB_DAT64 + -- : BFD_RELOC_SH_JMP_SLOT64 + -- : BFD_RELOC_SH_RELATIVE64 + -- : BFD_RELOC_SH_GOT10BY4 + -- : BFD_RELOC_SH_GOT10BY8 + -- : BFD_RELOC_SH_GOTPLT10BY4 + -- : BFD_RELOC_SH_GOTPLT10BY8 + -- : BFD_RELOC_SH_GOTPLT32 + -- : BFD_RELOC_SH_SHMEDIA_CODE + -- : BFD_RELOC_SH_IMMU5 + -- : BFD_RELOC_SH_IMMS6 + -- : BFD_RELOC_SH_IMMS6BY32 + -- : BFD_RELOC_SH_IMMU6 + -- : BFD_RELOC_SH_IMMS10 + -- : BFD_RELOC_SH_IMMS10BY2 + -- : BFD_RELOC_SH_IMMS10BY4 + -- : BFD_RELOC_SH_IMMS10BY8 + -- : BFD_RELOC_SH_IMMS16 + -- : BFD_RELOC_SH_IMMU16 + -- : BFD_RELOC_SH_IMM_LOW16 + -- : BFD_RELOC_SH_IMM_LOW16_PCREL + -- : BFD_RELOC_SH_IMM_MEDLOW16 + -- : BFD_RELOC_SH_IMM_MEDLOW16_PCREL + -- : BFD_RELOC_SH_IMM_MEDHI16 + -- : BFD_RELOC_SH_IMM_MEDHI16_PCREL + -- : BFD_RELOC_SH_IMM_HI16 + -- : BFD_RELOC_SH_IMM_HI16_PCREL + -- : BFD_RELOC_SH_PT_16 + -- : BFD_RELOC_SH_TLS_GD_32 + -- : BFD_RELOC_SH_TLS_LD_32 + -- : BFD_RELOC_SH_TLS_LDO_32 + -- : BFD_RELOC_SH_TLS_IE_32 + -- : BFD_RELOC_SH_TLS_LE_32 + -- : BFD_RELOC_SH_TLS_DTPMOD32 + -- : BFD_RELOC_SH_TLS_DTPOFF32 + -- : BFD_RELOC_SH_TLS_TPOFF32 + Renesas / SuperH SH relocs. Not all of these appear in object + files. + + -- : BFD_RELOC_ARC_B22_PCREL + ARC Cores relocs. ARC 22 bit pc-relative branch. The lowest two + bits must be zero and are not stored in the instruction. The high + 20 bits are installed in bits 26 through 7 of the instruction. + + -- : BFD_RELOC_ARC_B26 + ARC 26 bit absolute branch. The lowest two bits must be zero and + are not stored in the instruction. The high 24 bits are installed + in bits 23 through 0. + + -- : BFD_RELOC_BFIN_16_IMM + ADI Blackfin 16 bit immediate absolute reloc. + + -- : BFD_RELOC_BFIN_16_HIGH + ADI Blackfin 16 bit immediate absolute reloc higher 16 bits. + + -- : BFD_RELOC_BFIN_4_PCREL + ADI Blackfin 'a' part of LSETUP. + + -- : BFD_RELOC_BFIN_5_PCREL + ADI Blackfin. + + -- : BFD_RELOC_BFIN_16_LOW + ADI Blackfin 16 bit immediate absolute reloc lower 16 bits. + + -- : BFD_RELOC_BFIN_10_PCREL + ADI Blackfin. + + -- : BFD_RELOC_BFIN_11_PCREL + ADI Blackfin 'b' part of LSETUP. + + -- : BFD_RELOC_BFIN_12_PCREL_JUMP + ADI Blackfin. + + -- : BFD_RELOC_BFIN_12_PCREL_JUMP_S + ADI Blackfin Short jump, pcrel. + + -- : BFD_RELOC_BFIN_24_PCREL_CALL_X + ADI Blackfin Call.x not implemented. + + -- : BFD_RELOC_BFIN_24_PCREL_JUMP_L + ADI Blackfin Long Jump pcrel. + + -- : BFD_RELOC_BFIN_GOT17M4 + -- : BFD_RELOC_BFIN_GOTHI + -- : BFD_RELOC_BFIN_GOTLO + -- : BFD_RELOC_BFIN_FUNCDESC + -- : BFD_RELOC_BFIN_FUNCDESC_GOT17M4 + -- : BFD_RELOC_BFIN_FUNCDESC_GOTHI + -- : BFD_RELOC_BFIN_FUNCDESC_GOTLO + -- : BFD_RELOC_BFIN_FUNCDESC_VALUE + -- : BFD_RELOC_BFIN_FUNCDESC_GOTOFF17M4 + -- : BFD_RELOC_BFIN_FUNCDESC_GOTOFFHI + -- : BFD_RELOC_BFIN_FUNCDESC_GOTOFFLO + -- : BFD_RELOC_BFIN_GOTOFF17M4 + -- : BFD_RELOC_BFIN_GOTOFFHI + -- : BFD_RELOC_BFIN_GOTOFFLO + ADI Blackfin FD-PIC relocations. + + -- : BFD_RELOC_BFIN_GOT + ADI Blackfin GOT relocation. + + -- : BFD_RELOC_BFIN_PLTPC + ADI Blackfin PLTPC relocation. + + -- : BFD_ARELOC_BFIN_PUSH + ADI Blackfin arithmetic relocation. + + -- : BFD_ARELOC_BFIN_CONST + ADI Blackfin arithmetic relocation. + + -- : BFD_ARELOC_BFIN_ADD + ADI Blackfin arithmetic relocation. + + -- : BFD_ARELOC_BFIN_SUB + ADI Blackfin arithmetic relocation. + + -- : BFD_ARELOC_BFIN_MULT + ADI Blackfin arithmetic relocation. + + -- : BFD_ARELOC_BFIN_DIV + ADI Blackfin arithmetic relocation. + + -- : BFD_ARELOC_BFIN_MOD + ADI Blackfin arithmetic relocation. + + -- : BFD_ARELOC_BFIN_LSHIFT + ADI Blackfin arithmetic relocation. + + -- : BFD_ARELOC_BFIN_RSHIFT + ADI Blackfin arithmetic relocation. + + -- : BFD_ARELOC_BFIN_AND + ADI Blackfin arithmetic relocation. + + -- : BFD_ARELOC_BFIN_OR + ADI Blackfin arithmetic relocation. + + -- : BFD_ARELOC_BFIN_XOR + ADI Blackfin arithmetic relocation. + + -- : BFD_ARELOC_BFIN_LAND + ADI Blackfin arithmetic relocation. + + -- : BFD_ARELOC_BFIN_LOR + ADI Blackfin arithmetic relocation. + + -- : BFD_ARELOC_BFIN_LEN + ADI Blackfin arithmetic relocation. + + -- : BFD_ARELOC_BFIN_NEG + ADI Blackfin arithmetic relocation. + + -- : BFD_ARELOC_BFIN_COMP + ADI Blackfin arithmetic relocation. + + -- : BFD_ARELOC_BFIN_PAGE + ADI Blackfin arithmetic relocation. + + -- : BFD_ARELOC_BFIN_HWPAGE + ADI Blackfin arithmetic relocation. + + -- : BFD_ARELOC_BFIN_ADDR + ADI Blackfin arithmetic relocation. + + -- : BFD_RELOC_D10V_10_PCREL_R + Mitsubishi D10V relocs. This is a 10-bit reloc with the right 2 + bits assumed to be 0. + + -- : BFD_RELOC_D10V_10_PCREL_L + Mitsubishi D10V relocs. This is a 10-bit reloc with the right 2 + bits assumed to be 0. This is the same as the previous reloc + except it is in the left container, i.e., shifted left 15 bits. + + -- : BFD_RELOC_D10V_18 + This is an 18-bit reloc with the right 2 bits assumed to be 0. + + -- : BFD_RELOC_D10V_18_PCREL + This is an 18-bit reloc with the right 2 bits assumed to be 0. + + -- : BFD_RELOC_D30V_6 + Mitsubishi D30V relocs. This is a 6-bit absolute reloc. + + -- : BFD_RELOC_D30V_9_PCREL + This is a 6-bit pc-relative reloc with the right 3 bits assumed to + be 0. + + -- : BFD_RELOC_D30V_9_PCREL_R + This is a 6-bit pc-relative reloc with the right 3 bits assumed to + be 0. Same as the previous reloc but on the right side of the + container. + + -- : BFD_RELOC_D30V_15 + This is a 12-bit absolute reloc with the right 3 bitsassumed to be + 0. + + -- : BFD_RELOC_D30V_15_PCREL + This is a 12-bit pc-relative reloc with the right 3 bits assumed + to be 0. + + -- : BFD_RELOC_D30V_15_PCREL_R + This is a 12-bit pc-relative reloc with the right 3 bits assumed + to be 0. Same as the previous reloc but on the right side of the + container. + + -- : BFD_RELOC_D30V_21 + This is an 18-bit absolute reloc with the right 3 bits assumed to + be 0. + + -- : BFD_RELOC_D30V_21_PCREL + This is an 18-bit pc-relative reloc with the right 3 bits assumed + to be 0. + + -- : BFD_RELOC_D30V_21_PCREL_R + This is an 18-bit pc-relative reloc with the right 3 bits assumed + to be 0. Same as the previous reloc but on the right side of the + container. + + -- : BFD_RELOC_D30V_32 + This is a 32-bit absolute reloc. + + -- : BFD_RELOC_D30V_32_PCREL + This is a 32-bit pc-relative reloc. + + -- : BFD_RELOC_DLX_HI16_S + DLX relocs + + -- : BFD_RELOC_DLX_LO16 + DLX relocs + + -- : BFD_RELOC_DLX_JMP26 + DLX relocs + + -- : BFD_RELOC_M32C_HI8 + -- : BFD_RELOC_M32C_RL_JUMP + -- : BFD_RELOC_M32C_RL_1ADDR + -- : BFD_RELOC_M32C_RL_2ADDR + Renesas M16C/M32C Relocations. + + -- : BFD_RELOC_M32R_24 + Renesas M32R (formerly Mitsubishi M32R) relocs. This is a 24 bit + absolute address. + + -- : BFD_RELOC_M32R_10_PCREL + This is a 10-bit pc-relative reloc with the right 2 bits assumed + to be 0. + + -- : BFD_RELOC_M32R_18_PCREL + This is an 18-bit reloc with the right 2 bits assumed to be 0. + + -- : BFD_RELOC_M32R_26_PCREL + This is a 26-bit reloc with the right 2 bits assumed to be 0. + + -- : BFD_RELOC_M32R_HI16_ULO + This is a 16-bit reloc containing the high 16 bits of an address + used when the lower 16 bits are treated as unsigned. + + -- : BFD_RELOC_M32R_HI16_SLO + This is a 16-bit reloc containing the high 16 bits of an address + used when the lower 16 bits are treated as signed. + + -- : BFD_RELOC_M32R_LO16 + This is a 16-bit reloc containing the lower 16 bits of an address. + + -- : BFD_RELOC_M32R_SDA16 + This is a 16-bit reloc containing the small data area offset for + use in add3, load, and store instructions. + + -- : BFD_RELOC_M32R_GOT24 + -- : BFD_RELOC_M32R_26_PLTREL + -- : BFD_RELOC_M32R_COPY + -- : BFD_RELOC_M32R_GLOB_DAT + -- : BFD_RELOC_M32R_JMP_SLOT + -- : BFD_RELOC_M32R_RELATIVE + -- : BFD_RELOC_M32R_GOTOFF + -- : BFD_RELOC_M32R_GOTOFF_HI_ULO + -- : BFD_RELOC_M32R_GOTOFF_HI_SLO + -- : BFD_RELOC_M32R_GOTOFF_LO + -- : BFD_RELOC_M32R_GOTPC24 + -- : BFD_RELOC_M32R_GOT16_HI_ULO + -- : BFD_RELOC_M32R_GOT16_HI_SLO + -- : BFD_RELOC_M32R_GOT16_LO + -- : BFD_RELOC_M32R_GOTPC_HI_ULO + -- : BFD_RELOC_M32R_GOTPC_HI_SLO + -- : BFD_RELOC_M32R_GOTPC_LO + For PIC. + + -- : BFD_RELOC_V850_9_PCREL + This is a 9-bit reloc + + -- : BFD_RELOC_V850_22_PCREL + This is a 22-bit reloc + + -- : BFD_RELOC_V850_SDA_16_16_OFFSET + This is a 16 bit offset from the short data area pointer. + + -- : BFD_RELOC_V850_SDA_15_16_OFFSET + This is a 16 bit offset (of which only 15 bits are used) from the + short data area pointer. + + -- : BFD_RELOC_V850_ZDA_16_16_OFFSET + This is a 16 bit offset from the zero data area pointer. + + -- : BFD_RELOC_V850_ZDA_15_16_OFFSET + This is a 16 bit offset (of which only 15 bits are used) from the + zero data area pointer. + + -- : BFD_RELOC_V850_TDA_6_8_OFFSET + This is an 8 bit offset (of which only 6 bits are used) from the + tiny data area pointer. + + -- : BFD_RELOC_V850_TDA_7_8_OFFSET + This is an 8bit offset (of which only 7 bits are used) from the + tiny data area pointer. + + -- : BFD_RELOC_V850_TDA_7_7_OFFSET + This is a 7 bit offset from the tiny data area pointer. + + -- : BFD_RELOC_V850_TDA_16_16_OFFSET + This is a 16 bit offset from the tiny data area pointer. + + -- : BFD_RELOC_V850_TDA_4_5_OFFSET + This is a 5 bit offset (of which only 4 bits are used) from the + tiny data area pointer. + + -- : BFD_RELOC_V850_TDA_4_4_OFFSET + This is a 4 bit offset from the tiny data area pointer. + + -- : BFD_RELOC_V850_SDA_16_16_SPLIT_OFFSET + This is a 16 bit offset from the short data area pointer, with the + bits placed non-contiguously in the instruction. + + -- : BFD_RELOC_V850_ZDA_16_16_SPLIT_OFFSET + This is a 16 bit offset from the zero data area pointer, with the + bits placed non-contiguously in the instruction. + + -- : BFD_RELOC_V850_CALLT_6_7_OFFSET + This is a 6 bit offset from the call table base pointer. + + -- : BFD_RELOC_V850_CALLT_16_16_OFFSET + This is a 16 bit offset from the call table base pointer. + + -- : BFD_RELOC_V850_LONGCALL + Used for relaxing indirect function calls. + + -- : BFD_RELOC_V850_LONGJUMP + Used for relaxing indirect jumps. + + -- : BFD_RELOC_V850_ALIGN + Used to maintain alignment whilst relaxing. + + -- : BFD_RELOC_V850_LO16_SPLIT_OFFSET + This is a variation of BFD_RELOC_LO16 that can be used in v850e + ld.bu instructions. + + -- : BFD_RELOC_MN10300_32_PCREL + This is a 32bit pcrel reloc for the mn10300, offset by two bytes + in the instruction. + + -- : BFD_RELOC_MN10300_16_PCREL + This is a 16bit pcrel reloc for the mn10300, offset by two bytes + in the instruction. + + -- : BFD_RELOC_TIC30_LDP + This is a 8bit DP reloc for the tms320c30, where the most + significant 8 bits of a 24 bit word are placed into the least + significant 8 bits of the opcode. + + -- : BFD_RELOC_TIC54X_PARTLS7 + This is a 7bit reloc for the tms320c54x, where the least + significant 7 bits of a 16 bit word are placed into the least + significant 7 bits of the opcode. + + -- : BFD_RELOC_TIC54X_PARTMS9 + This is a 9bit DP reloc for the tms320c54x, where the most + significant 9 bits of a 16 bit word are placed into the least + significant 9 bits of the opcode. + + -- : BFD_RELOC_TIC54X_23 + This is an extended address 23-bit reloc for the tms320c54x. + + -- : BFD_RELOC_TIC54X_16_OF_23 + This is a 16-bit reloc for the tms320c54x, where the least + significant 16 bits of a 23-bit extended address are placed into + the opcode. + + -- : BFD_RELOC_TIC54X_MS7_OF_23 + This is a reloc for the tms320c54x, where the most significant 7 + bits of a 23-bit extended address are placed into the opcode. + + -- : BFD_RELOC_FR30_48 + This is a 48 bit reloc for the FR30 that stores 32 bits. + + -- : BFD_RELOC_FR30_20 + This is a 32 bit reloc for the FR30 that stores 20 bits split up + into two sections. + + -- : BFD_RELOC_FR30_6_IN_4 + This is a 16 bit reloc for the FR30 that stores a 6 bit word + offset in 4 bits. + + -- : BFD_RELOC_FR30_8_IN_8 + This is a 16 bit reloc for the FR30 that stores an 8 bit byte + offset into 8 bits. + + -- : BFD_RELOC_FR30_9_IN_8 + This is a 16 bit reloc for the FR30 that stores a 9 bit short + offset into 8 bits. + + -- : BFD_RELOC_FR30_10_IN_8 + This is a 16 bit reloc for the FR30 that stores a 10 bit word + offset into 8 bits. + + -- : BFD_RELOC_FR30_9_PCREL + This is a 16 bit reloc for the FR30 that stores a 9 bit pc relative + short offset into 8 bits. + + -- : BFD_RELOC_FR30_12_PCREL + This is a 16 bit reloc for the FR30 that stores a 12 bit pc + relative short offset into 11 bits. + + -- : BFD_RELOC_MCORE_PCREL_IMM8BY4 + -- : BFD_RELOC_MCORE_PCREL_IMM11BY2 + -- : BFD_RELOC_MCORE_PCREL_IMM4BY2 + -- : BFD_RELOC_MCORE_PCREL_32 + -- : BFD_RELOC_MCORE_PCREL_JSR_IMM11BY2 + -- : BFD_RELOC_MCORE_RVA + Motorola Mcore relocations. + + -- : BFD_RELOC_MEP_8 + -- : BFD_RELOC_MEP_16 + -- : BFD_RELOC_MEP_32 + -- : BFD_RELOC_MEP_PCREL8A2 + -- : BFD_RELOC_MEP_PCREL12A2 + -- : BFD_RELOC_MEP_PCREL17A2 + -- : BFD_RELOC_MEP_PCREL24A2 + -- : BFD_RELOC_MEP_PCABS24A2 + -- : BFD_RELOC_MEP_LOW16 + -- : BFD_RELOC_MEP_HI16U + -- : BFD_RELOC_MEP_HI16S + -- : BFD_RELOC_MEP_GPREL + -- : BFD_RELOC_MEP_TPREL + -- : BFD_RELOC_MEP_TPREL7 + -- : BFD_RELOC_MEP_TPREL7A2 + -- : BFD_RELOC_MEP_TPREL7A4 + -- : BFD_RELOC_MEP_UIMM24 + -- : BFD_RELOC_MEP_ADDR24A4 + -- : BFD_RELOC_MEP_GNU_VTINHERIT + -- : BFD_RELOC_MEP_GNU_VTENTRY + Toshiba Media Processor Relocations. + + -- : BFD_RELOC_MMIX_GETA + -- : BFD_RELOC_MMIX_GETA_1 + -- : BFD_RELOC_MMIX_GETA_2 + -- : BFD_RELOC_MMIX_GETA_3 + These are relocations for the GETA instruction. + + -- : BFD_RELOC_MMIX_CBRANCH + -- : BFD_RELOC_MMIX_CBRANCH_J + -- : BFD_RELOC_MMIX_CBRANCH_1 + -- : BFD_RELOC_MMIX_CBRANCH_2 + -- : BFD_RELOC_MMIX_CBRANCH_3 + These are relocations for a conditional branch instruction. + + -- : BFD_RELOC_MMIX_PUSHJ + -- : BFD_RELOC_MMIX_PUSHJ_1 + -- : BFD_RELOC_MMIX_PUSHJ_2 + -- : BFD_RELOC_MMIX_PUSHJ_3 + -- : BFD_RELOC_MMIX_PUSHJ_STUBBABLE + These are relocations for the PUSHJ instruction. + + -- : BFD_RELOC_MMIX_JMP + -- : BFD_RELOC_MMIX_JMP_1 + -- : BFD_RELOC_MMIX_JMP_2 + -- : BFD_RELOC_MMIX_JMP_3 + These are relocations for the JMP instruction. + + -- : BFD_RELOC_MMIX_ADDR19 + This is a relocation for a relative address as in a GETA + instruction or a branch. + + -- : BFD_RELOC_MMIX_ADDR27 + This is a relocation for a relative address as in a JMP + instruction. + + -- : BFD_RELOC_MMIX_REG_OR_BYTE + This is a relocation for an instruction field that may be a general + register or a value 0..255. + + -- : BFD_RELOC_MMIX_REG + This is a relocation for an instruction field that may be a general + register. + + -- : BFD_RELOC_MMIX_BASE_PLUS_OFFSET + This is a relocation for two instruction fields holding a register + and an offset, the equivalent of the relocation. + + -- : BFD_RELOC_MMIX_LOCAL + This relocation is an assertion that the expression is not + allocated as a global register. It does not modify contents. + + -- : BFD_RELOC_AVR_7_PCREL + This is a 16 bit reloc for the AVR that stores 8 bit pc relative + short offset into 7 bits. + + -- : BFD_RELOC_AVR_13_PCREL + This is a 16 bit reloc for the AVR that stores 13 bit pc relative + short offset into 12 bits. + + -- : BFD_RELOC_AVR_16_PM + This is a 16 bit reloc for the AVR that stores 17 bit value + (usually program memory address) into 16 bits. + + -- : BFD_RELOC_AVR_LO8_LDI + This is a 16 bit reloc for the AVR that stores 8 bit value (usually + data memory address) into 8 bit immediate value of LDI insn. + + -- : BFD_RELOC_AVR_HI8_LDI + This is a 16 bit reloc for the AVR that stores 8 bit value (high 8 + bit of data memory address) into 8 bit immediate value of LDI insn. + + -- : BFD_RELOC_AVR_HH8_LDI + This is a 16 bit reloc for the AVR that stores 8 bit value (most + high 8 bit of program memory address) into 8 bit immediate value + of LDI insn. + + -- : BFD_RELOC_AVR_MS8_LDI + This is a 16 bit reloc for the AVR that stores 8 bit value (most + high 8 bit of 32 bit value) into 8 bit immediate value of LDI insn. + + -- : BFD_RELOC_AVR_LO8_LDI_NEG + This is a 16 bit reloc for the AVR that stores negated 8 bit value + (usually data memory address) into 8 bit immediate value of SUBI + insn. + + -- : BFD_RELOC_AVR_HI8_LDI_NEG + This is a 16 bit reloc for the AVR that stores negated 8 bit value + (high 8 bit of data memory address) into 8 bit immediate value of + SUBI insn. + + -- : BFD_RELOC_AVR_HH8_LDI_NEG + This is a 16 bit reloc for the AVR that stores negated 8 bit value + (most high 8 bit of program memory address) into 8 bit immediate + value of LDI or SUBI insn. + + -- : BFD_RELOC_AVR_MS8_LDI_NEG + This is a 16 bit reloc for the AVR that stores negated 8 bit value + (msb of 32 bit value) into 8 bit immediate value of LDI insn. + + -- : BFD_RELOC_AVR_LO8_LDI_PM + This is a 16 bit reloc for the AVR that stores 8 bit value (usually + command address) into 8 bit immediate value of LDI insn. + + -- : BFD_RELOC_AVR_LO8_LDI_GS + This is a 16 bit reloc for the AVR that stores 8 bit value + (command address) into 8 bit immediate value of LDI insn. If the + address is beyond the 128k boundary, the linker inserts a jump + stub for this reloc in the lower 128k. + + -- : BFD_RELOC_AVR_HI8_LDI_PM + This is a 16 bit reloc for the AVR that stores 8 bit value (high 8 + bit of command address) into 8 bit immediate value of LDI insn. + + -- : BFD_RELOC_AVR_HI8_LDI_GS + This is a 16 bit reloc for the AVR that stores 8 bit value (high 8 + bit of command address) into 8 bit immediate value of LDI insn. + If the address is beyond the 128k boundary, the linker inserts a + jump stub for this reloc below 128k. + + -- : BFD_RELOC_AVR_HH8_LDI_PM + This is a 16 bit reloc for the AVR that stores 8 bit value (most + high 8 bit of command address) into 8 bit immediate value of LDI + insn. + + -- : BFD_RELOC_AVR_LO8_LDI_PM_NEG + This is a 16 bit reloc for the AVR that stores negated 8 bit value + (usually command address) into 8 bit immediate value of SUBI insn. + + -- : BFD_RELOC_AVR_HI8_LDI_PM_NEG + This is a 16 bit reloc for the AVR that stores negated 8 bit value + (high 8 bit of 16 bit command address) into 8 bit immediate value + of SUBI insn. + + -- : BFD_RELOC_AVR_HH8_LDI_PM_NEG + This is a 16 bit reloc for the AVR that stores negated 8 bit value + (high 6 bit of 22 bit command address) into 8 bit immediate value + of SUBI insn. + + -- : BFD_RELOC_AVR_CALL + This is a 32 bit reloc for the AVR that stores 23 bit value into + 22 bits. + + -- : BFD_RELOC_AVR_LDI + This is a 16 bit reloc for the AVR that stores all needed bits for + absolute addressing with ldi with overflow check to linktime + + -- : BFD_RELOC_AVR_6 + This is a 6 bit reloc for the AVR that stores offset for ldd/std + instructions + + -- : BFD_RELOC_AVR_6_ADIW + This is a 6 bit reloc for the AVR that stores offset for adiw/sbiw + instructions + + -- : BFD_RELOC_390_12 + Direct 12 bit. + + -- : BFD_RELOC_390_GOT12 + 12 bit GOT offset. + + -- : BFD_RELOC_390_PLT32 + 32 bit PC relative PLT address. + + -- : BFD_RELOC_390_COPY + Copy symbol at runtime. + + -- : BFD_RELOC_390_GLOB_DAT + Create GOT entry. + + -- : BFD_RELOC_390_JMP_SLOT + Create PLT entry. + + -- : BFD_RELOC_390_RELATIVE + Adjust by program base. + + -- : BFD_RELOC_390_GOTPC + 32 bit PC relative offset to GOT. + + -- : BFD_RELOC_390_GOT16 + 16 bit GOT offset. + + -- : BFD_RELOC_390_PC16DBL + PC relative 16 bit shifted by 1. + + -- : BFD_RELOC_390_PLT16DBL + 16 bit PC rel. PLT shifted by 1. + + -- : BFD_RELOC_390_PC32DBL + PC relative 32 bit shifted by 1. + + -- : BFD_RELOC_390_PLT32DBL + 32 bit PC rel. PLT shifted by 1. + + -- : BFD_RELOC_390_GOTPCDBL + 32 bit PC rel. GOT shifted by 1. + + -- : BFD_RELOC_390_GOT64 + 64 bit GOT offset. + + -- : BFD_RELOC_390_PLT64 + 64 bit PC relative PLT address. + + -- : BFD_RELOC_390_GOTENT + 32 bit rel. offset to GOT entry. + + -- : BFD_RELOC_390_GOTOFF64 + 64 bit offset to GOT. + + -- : BFD_RELOC_390_GOTPLT12 + 12-bit offset to symbol-entry within GOT, with PLT handling. + + -- : BFD_RELOC_390_GOTPLT16 + 16-bit offset to symbol-entry within GOT, with PLT handling. + + -- : BFD_RELOC_390_GOTPLT32 + 32-bit offset to symbol-entry within GOT, with PLT handling. + + -- : BFD_RELOC_390_GOTPLT64 + 64-bit offset to symbol-entry within GOT, with PLT handling. + + -- : BFD_RELOC_390_GOTPLTENT + 32-bit rel. offset to symbol-entry within GOT, with PLT handling. + + -- : BFD_RELOC_390_PLTOFF16 + 16-bit rel. offset from the GOT to a PLT entry. + + -- : BFD_RELOC_390_PLTOFF32 + 32-bit rel. offset from the GOT to a PLT entry. + + -- : BFD_RELOC_390_PLTOFF64 + 64-bit rel. offset from the GOT to a PLT entry. + + -- : BFD_RELOC_390_TLS_LOAD + -- : BFD_RELOC_390_TLS_GDCALL + -- : BFD_RELOC_390_TLS_LDCALL + -- : BFD_RELOC_390_TLS_GD32 + -- : BFD_RELOC_390_TLS_GD64 + -- : BFD_RELOC_390_TLS_GOTIE12 + -- : BFD_RELOC_390_TLS_GOTIE32 + -- : BFD_RELOC_390_TLS_GOTIE64 + -- : BFD_RELOC_390_TLS_LDM32 + -- : BFD_RELOC_390_TLS_LDM64 + -- : BFD_RELOC_390_TLS_IE32 + -- : BFD_RELOC_390_TLS_IE64 + -- : BFD_RELOC_390_TLS_IEENT + -- : BFD_RELOC_390_TLS_LE32 + -- : BFD_RELOC_390_TLS_LE64 + -- : BFD_RELOC_390_TLS_LDO32 + -- : BFD_RELOC_390_TLS_LDO64 + -- : BFD_RELOC_390_TLS_DTPMOD + -- : BFD_RELOC_390_TLS_DTPOFF + -- : BFD_RELOC_390_TLS_TPOFF + s390 tls relocations. + + -- : BFD_RELOC_390_20 + -- : BFD_RELOC_390_GOT20 + -- : BFD_RELOC_390_GOTPLT20 + -- : BFD_RELOC_390_TLS_GOTIE20 + Long displacement extension. + + -- : BFD_RELOC_SCORE_GPREL15 + Score relocations Low 16 bit for load/store + + -- : BFD_RELOC_SCORE_DUMMY2 + -- : BFD_RELOC_SCORE_JMP + This is a 24-bit reloc with the right 1 bit assumed to be 0 + + -- : BFD_RELOC_SCORE_BRANCH + This is a 19-bit reloc with the right 1 bit assumed to be 0 + + -- : BFD_RELOC_SCORE_IMM30 + This is a 32-bit reloc for 48-bit instructions. + + -- : BFD_RELOC_SCORE_IMM32 + This is a 32-bit reloc for 48-bit instructions. + + -- : BFD_RELOC_SCORE16_JMP + This is a 11-bit reloc with the right 1 bit assumed to be 0 + + -- : BFD_RELOC_SCORE16_BRANCH + This is a 8-bit reloc with the right 1 bit assumed to be 0 + + -- : BFD_RELOC_SCORE_BCMP + This is a 9-bit reloc with the right 1 bit assumed to be 0 + + -- : BFD_RELOC_SCORE_GOT15 + -- : BFD_RELOC_SCORE_GOT_LO16 + -- : BFD_RELOC_SCORE_CALL15 + -- : BFD_RELOC_SCORE_DUMMY_HI16 + Undocumented Score relocs + + -- : BFD_RELOC_IP2K_FR9 + Scenix IP2K - 9-bit register number / data address + + -- : BFD_RELOC_IP2K_BANK + Scenix IP2K - 4-bit register/data bank number + + -- : BFD_RELOC_IP2K_ADDR16CJP + Scenix IP2K - low 13 bits of instruction word address + + -- : BFD_RELOC_IP2K_PAGE3 + Scenix IP2K - high 3 bits of instruction word address + + -- : BFD_RELOC_IP2K_LO8DATA + -- : BFD_RELOC_IP2K_HI8DATA + -- : BFD_RELOC_IP2K_EX8DATA + Scenix IP2K - ext/low/high 8 bits of data address + + -- : BFD_RELOC_IP2K_LO8INSN + -- : BFD_RELOC_IP2K_HI8INSN + Scenix IP2K - low/high 8 bits of instruction word address + + -- : BFD_RELOC_IP2K_PC_SKIP + Scenix IP2K - even/odd PC modifier to modify snb pcl.0 + + -- : BFD_RELOC_IP2K_TEXT + Scenix IP2K - 16 bit word address in text section. + + -- : BFD_RELOC_IP2K_FR_OFFSET + Scenix IP2K - 7-bit sp or dp offset + + -- : BFD_RELOC_VPE4KMATH_DATA + -- : BFD_RELOC_VPE4KMATH_INSN + Scenix VPE4K coprocessor - data/insn-space addressing + + -- : BFD_RELOC_VTABLE_INHERIT + -- : BFD_RELOC_VTABLE_ENTRY + These two relocations are used by the linker to determine which of + the entries in a C++ virtual function table are actually used. + When the -gc-sections option is given, the linker will zero out + the entries that are not used, so that the code for those + functions need not be included in the output. + + VTABLE_INHERIT is a zero-space relocation used to describe to the + linker the inheritance tree of a C++ virtual function table. The + relocation's symbol should be the parent class' vtable, and the + relocation should be located at the child vtable. + + VTABLE_ENTRY is a zero-space relocation that describes the use of a + virtual function table entry. The reloc's symbol should refer to + the table of the class mentioned in the code. Off of that base, + an offset describes the entry that is being used. For Rela hosts, + this offset is stored in the reloc's addend. For Rel hosts, we + are forced to put this offset in the reloc's section offset. + + -- : BFD_RELOC_IA64_IMM14 + -- : BFD_RELOC_IA64_IMM22 + -- : BFD_RELOC_IA64_IMM64 + -- : BFD_RELOC_IA64_DIR32MSB + -- : BFD_RELOC_IA64_DIR32LSB + -- : BFD_RELOC_IA64_DIR64MSB + -- : BFD_RELOC_IA64_DIR64LSB + -- : BFD_RELOC_IA64_GPREL22 + -- : BFD_RELOC_IA64_GPREL64I + -- : BFD_RELOC_IA64_GPREL32MSB + -- : BFD_RELOC_IA64_GPREL32LSB + -- : BFD_RELOC_IA64_GPREL64MSB + -- : BFD_RELOC_IA64_GPREL64LSB + -- : BFD_RELOC_IA64_LTOFF22 + -- : BFD_RELOC_IA64_LTOFF64I + -- : BFD_RELOC_IA64_PLTOFF22 + -- : BFD_RELOC_IA64_PLTOFF64I + -- : BFD_RELOC_IA64_PLTOFF64MSB + -- : BFD_RELOC_IA64_PLTOFF64LSB + -- : BFD_RELOC_IA64_FPTR64I + -- : BFD_RELOC_IA64_FPTR32MSB + -- : BFD_RELOC_IA64_FPTR32LSB + -- : BFD_RELOC_IA64_FPTR64MSB + -- : BFD_RELOC_IA64_FPTR64LSB + -- : BFD_RELOC_IA64_PCREL21B + -- : BFD_RELOC_IA64_PCREL21BI + -- : BFD_RELOC_IA64_PCREL21M + -- : BFD_RELOC_IA64_PCREL21F + -- : BFD_RELOC_IA64_PCREL22 + -- : BFD_RELOC_IA64_PCREL60B + -- : BFD_RELOC_IA64_PCREL64I + -- : BFD_RELOC_IA64_PCREL32MSB + -- : BFD_RELOC_IA64_PCREL32LSB + -- : BFD_RELOC_IA64_PCREL64MSB + -- : BFD_RELOC_IA64_PCREL64LSB + -- : BFD_RELOC_IA64_LTOFF_FPTR22 + -- : BFD_RELOC_IA64_LTOFF_FPTR64I + -- : BFD_RELOC_IA64_LTOFF_FPTR32MSB + -- : BFD_RELOC_IA64_LTOFF_FPTR32LSB + -- : BFD_RELOC_IA64_LTOFF_FPTR64MSB + -- : BFD_RELOC_IA64_LTOFF_FPTR64LSB + -- : BFD_RELOC_IA64_SEGREL32MSB + -- : BFD_RELOC_IA64_SEGREL32LSB + -- : BFD_RELOC_IA64_SEGREL64MSB + -- : BFD_RELOC_IA64_SEGREL64LSB + -- : BFD_RELOC_IA64_SECREL32MSB + -- : BFD_RELOC_IA64_SECREL32LSB + -- : BFD_RELOC_IA64_SECREL64MSB + -- : BFD_RELOC_IA64_SECREL64LSB + -- : BFD_RELOC_IA64_REL32MSB + -- : BFD_RELOC_IA64_REL32LSB + -- : BFD_RELOC_IA64_REL64MSB + -- : BFD_RELOC_IA64_REL64LSB + -- : BFD_RELOC_IA64_LTV32MSB + -- : BFD_RELOC_IA64_LTV32LSB + -- : BFD_RELOC_IA64_LTV64MSB + -- : BFD_RELOC_IA64_LTV64LSB + -- : BFD_RELOC_IA64_IPLTMSB + -- : BFD_RELOC_IA64_IPLTLSB + -- : BFD_RELOC_IA64_COPY + -- : BFD_RELOC_IA64_LTOFF22X + -- : BFD_RELOC_IA64_LDXMOV + -- : BFD_RELOC_IA64_TPREL14 + -- : BFD_RELOC_IA64_TPREL22 + -- : BFD_RELOC_IA64_TPREL64I + -- : BFD_RELOC_IA64_TPREL64MSB + -- : BFD_RELOC_IA64_TPREL64LSB + -- : BFD_RELOC_IA64_LTOFF_TPREL22 + -- : BFD_RELOC_IA64_DTPMOD64MSB + -- : BFD_RELOC_IA64_DTPMOD64LSB + -- : BFD_RELOC_IA64_LTOFF_DTPMOD22 + -- : BFD_RELOC_IA64_DTPREL14 + -- : BFD_RELOC_IA64_DTPREL22 + -- : BFD_RELOC_IA64_DTPREL64I + -- : BFD_RELOC_IA64_DTPREL32MSB + -- : BFD_RELOC_IA64_DTPREL32LSB + -- : BFD_RELOC_IA64_DTPREL64MSB + -- : BFD_RELOC_IA64_DTPREL64LSB + -- : BFD_RELOC_IA64_LTOFF_DTPREL22 + Intel IA64 Relocations. + + -- : BFD_RELOC_M68HC11_HI8 + Motorola 68HC11 reloc. This is the 8 bit high part of an absolute + address. + + -- : BFD_RELOC_M68HC11_LO8 + Motorola 68HC11 reloc. This is the 8 bit low part of an absolute + address. + + -- : BFD_RELOC_M68HC11_3B + Motorola 68HC11 reloc. This is the 3 bit of a value. + + -- : BFD_RELOC_M68HC11_RL_JUMP + Motorola 68HC11 reloc. This reloc marks the beginning of a + jump/call instruction. It is used for linker relaxation to + correctly identify beginning of instruction and change some + branches to use PC-relative addressing mode. + + -- : BFD_RELOC_M68HC11_RL_GROUP + Motorola 68HC11 reloc. This reloc marks a group of several + instructions that gcc generates and for which the linker + relaxation pass can modify and/or remove some of them. + + -- : BFD_RELOC_M68HC11_LO16 + Motorola 68HC11 reloc. This is the 16-bit lower part of an + address. It is used for 'call' instruction to specify the symbol + address without any special transformation (due to memory bank + window). + + -- : BFD_RELOC_M68HC11_PAGE + Motorola 68HC11 reloc. This is a 8-bit reloc that specifies the + page number of an address. It is used by 'call' instruction to + specify the page number of the symbol. + + -- : BFD_RELOC_M68HC11_24 + Motorola 68HC11 reloc. This is a 24-bit reloc that represents the + address with a 16-bit value and a 8-bit page number. The symbol + address is transformed to follow the 16K memory bank of 68HC12 + (seen as mapped in the window). + + -- : BFD_RELOC_M68HC12_5B + Motorola 68HC12 reloc. This is the 5 bits of a value. + + -- : BFD_RELOC_16C_NUM08 + -- : BFD_RELOC_16C_NUM08_C + -- : BFD_RELOC_16C_NUM16 + -- : BFD_RELOC_16C_NUM16_C + -- : BFD_RELOC_16C_NUM32 + -- : BFD_RELOC_16C_NUM32_C + -- : BFD_RELOC_16C_DISP04 + -- : BFD_RELOC_16C_DISP04_C + -- : BFD_RELOC_16C_DISP08 + -- : BFD_RELOC_16C_DISP08_C + -- : BFD_RELOC_16C_DISP16 + -- : BFD_RELOC_16C_DISP16_C + -- : BFD_RELOC_16C_DISP24 + -- : BFD_RELOC_16C_DISP24_C + -- : BFD_RELOC_16C_DISP24a + -- : BFD_RELOC_16C_DISP24a_C + -- : BFD_RELOC_16C_REG04 + -- : BFD_RELOC_16C_REG04_C + -- : BFD_RELOC_16C_REG04a + -- : BFD_RELOC_16C_REG04a_C + -- : BFD_RELOC_16C_REG14 + -- : BFD_RELOC_16C_REG14_C + -- : BFD_RELOC_16C_REG16 + -- : BFD_RELOC_16C_REG16_C + -- : BFD_RELOC_16C_REG20 + -- : BFD_RELOC_16C_REG20_C + -- : BFD_RELOC_16C_ABS20 + -- : BFD_RELOC_16C_ABS20_C + -- : BFD_RELOC_16C_ABS24 + -- : BFD_RELOC_16C_ABS24_C + -- : BFD_RELOC_16C_IMM04 + -- : BFD_RELOC_16C_IMM04_C + -- : BFD_RELOC_16C_IMM16 + -- : BFD_RELOC_16C_IMM16_C + -- : BFD_RELOC_16C_IMM20 + -- : BFD_RELOC_16C_IMM20_C + -- : BFD_RELOC_16C_IMM24 + -- : BFD_RELOC_16C_IMM24_C + -- : BFD_RELOC_16C_IMM32 + -- : BFD_RELOC_16C_IMM32_C + NS CR16C Relocations. + + -- : BFD_RELOC_CR16_NUM8 + -- : BFD_RELOC_CR16_NUM16 + -- : BFD_RELOC_CR16_NUM32 + -- : BFD_RELOC_CR16_NUM32a + -- : BFD_RELOC_CR16_REGREL0 + -- : BFD_RELOC_CR16_REGREL4 + -- : BFD_RELOC_CR16_REGREL4a + -- : BFD_RELOC_CR16_REGREL14 + -- : BFD_RELOC_CR16_REGREL14a + -- : BFD_RELOC_CR16_REGREL16 + -- : BFD_RELOC_CR16_REGREL20 + -- : BFD_RELOC_CR16_REGREL20a + -- : BFD_RELOC_CR16_ABS20 + -- : BFD_RELOC_CR16_ABS24 + -- : BFD_RELOC_CR16_IMM4 + -- : BFD_RELOC_CR16_IMM8 + -- : BFD_RELOC_CR16_IMM16 + -- : BFD_RELOC_CR16_IMM20 + -- : BFD_RELOC_CR16_IMM24 + -- : BFD_RELOC_CR16_IMM32 + -- : BFD_RELOC_CR16_IMM32a + -- : BFD_RELOC_CR16_DISP4 + -- : BFD_RELOC_CR16_DISP8 + -- : BFD_RELOC_CR16_DISP16 + -- : BFD_RELOC_CR16_DISP20 + -- : BFD_RELOC_CR16_DISP24 + -- : BFD_RELOC_CR16_DISP24a + -- : BFD_RELOC_CR16_SWITCH8 + -- : BFD_RELOC_CR16_SWITCH16 + -- : BFD_RELOC_CR16_SWITCH32 + -- : BFD_RELOC_CR16_GOT_REGREL20 + -- : BFD_RELOC_CR16_GOTC_REGREL20 + -- : BFD_RELOC_CR16_GLOB_DAT + NS CR16 Relocations. + + -- : BFD_RELOC_CRX_REL4 + -- : BFD_RELOC_CRX_REL8 + -- : BFD_RELOC_CRX_REL8_CMP + -- : BFD_RELOC_CRX_REL16 + -- : BFD_RELOC_CRX_REL24 + -- : BFD_RELOC_CRX_REL32 + -- : BFD_RELOC_CRX_REGREL12 + -- : BFD_RELOC_CRX_REGREL22 + -- : BFD_RELOC_CRX_REGREL28 + -- : BFD_RELOC_CRX_REGREL32 + -- : BFD_RELOC_CRX_ABS16 + -- : BFD_RELOC_CRX_ABS32 + -- : BFD_RELOC_CRX_NUM8 + -- : BFD_RELOC_CRX_NUM16 + -- : BFD_RELOC_CRX_NUM32 + -- : BFD_RELOC_CRX_IMM16 + -- : BFD_RELOC_CRX_IMM32 + -- : BFD_RELOC_CRX_SWITCH8 + -- : BFD_RELOC_CRX_SWITCH16 + -- : BFD_RELOC_CRX_SWITCH32 + NS CRX Relocations. + + -- : BFD_RELOC_CRIS_BDISP8 + -- : BFD_RELOC_CRIS_UNSIGNED_5 + -- : BFD_RELOC_CRIS_SIGNED_6 + -- : BFD_RELOC_CRIS_UNSIGNED_6 + -- : BFD_RELOC_CRIS_SIGNED_8 + -- : BFD_RELOC_CRIS_UNSIGNED_8 + -- : BFD_RELOC_CRIS_SIGNED_16 + -- : BFD_RELOC_CRIS_UNSIGNED_16 + -- : BFD_RELOC_CRIS_LAPCQ_OFFSET + -- : BFD_RELOC_CRIS_UNSIGNED_4 + These relocs are only used within the CRIS assembler. They are not + (at present) written to any object files. + + -- : BFD_RELOC_CRIS_COPY + -- : BFD_RELOC_CRIS_GLOB_DAT + -- : BFD_RELOC_CRIS_JUMP_SLOT + -- : BFD_RELOC_CRIS_RELATIVE + Relocs used in ELF shared libraries for CRIS. + + -- : BFD_RELOC_CRIS_32_GOT + 32-bit offset to symbol-entry within GOT. + + -- : BFD_RELOC_CRIS_16_GOT + 16-bit offset to symbol-entry within GOT. + + -- : BFD_RELOC_CRIS_32_GOTPLT + 32-bit offset to symbol-entry within GOT, with PLT handling. + + -- : BFD_RELOC_CRIS_16_GOTPLT + 16-bit offset to symbol-entry within GOT, with PLT handling. + + -- : BFD_RELOC_CRIS_32_GOTREL + 32-bit offset to symbol, relative to GOT. + + -- : BFD_RELOC_CRIS_32_PLT_GOTREL + 32-bit offset to symbol with PLT entry, relative to GOT. + + -- : BFD_RELOC_CRIS_32_PLT_PCREL + 32-bit offset to symbol with PLT entry, relative to this + relocation. + + -- : BFD_RELOC_CRIS_32_GOT_GD + -- : BFD_RELOC_CRIS_16_GOT_GD + -- : BFD_RELOC_CRIS_32_GD + -- : BFD_RELOC_CRIS_DTP + -- : BFD_RELOC_CRIS_32_DTPREL + -- : BFD_RELOC_CRIS_16_DTPREL + -- : BFD_RELOC_CRIS_32_GOT_TPREL + -- : BFD_RELOC_CRIS_16_GOT_TPREL + -- : BFD_RELOC_CRIS_32_TPREL + -- : BFD_RELOC_CRIS_16_TPREL + -- : BFD_RELOC_CRIS_DTPMOD + -- : BFD_RELOC_CRIS_32_IE + Relocs used in TLS code for CRIS. + + -- : BFD_RELOC_860_COPY + -- : BFD_RELOC_860_GLOB_DAT + -- : BFD_RELOC_860_JUMP_SLOT + -- : BFD_RELOC_860_RELATIVE + -- : BFD_RELOC_860_PC26 + -- : BFD_RELOC_860_PLT26 + -- : BFD_RELOC_860_PC16 + -- : BFD_RELOC_860_LOW0 + -- : BFD_RELOC_860_SPLIT0 + -- : BFD_RELOC_860_LOW1 + -- : BFD_RELOC_860_SPLIT1 + -- : BFD_RELOC_860_LOW2 + -- : BFD_RELOC_860_SPLIT2 + -- : BFD_RELOC_860_LOW3 + -- : BFD_RELOC_860_LOGOT0 + -- : BFD_RELOC_860_SPGOT0 + -- : BFD_RELOC_860_LOGOT1 + -- : BFD_RELOC_860_SPGOT1 + -- : BFD_RELOC_860_LOGOTOFF0 + -- : BFD_RELOC_860_SPGOTOFF0 + -- : BFD_RELOC_860_LOGOTOFF1 + -- : BFD_RELOC_860_SPGOTOFF1 + -- : BFD_RELOC_860_LOGOTOFF2 + -- : BFD_RELOC_860_LOGOTOFF3 + -- : BFD_RELOC_860_LOPC + -- : BFD_RELOC_860_HIGHADJ + -- : BFD_RELOC_860_HAGOT + -- : BFD_RELOC_860_HAGOTOFF + -- : BFD_RELOC_860_HAPC + -- : BFD_RELOC_860_HIGH + -- : BFD_RELOC_860_HIGOT + -- : BFD_RELOC_860_HIGOTOFF + Intel i860 Relocations. + + -- : BFD_RELOC_OPENRISC_ABS_26 + -- : BFD_RELOC_OPENRISC_REL_26 + OpenRISC Relocations. + + -- : BFD_RELOC_H8_DIR16A8 + -- : BFD_RELOC_H8_DIR16R8 + -- : BFD_RELOC_H8_DIR24A8 + -- : BFD_RELOC_H8_DIR24R8 + -- : BFD_RELOC_H8_DIR32A16 + H8 elf Relocations. + + -- : BFD_RELOC_XSTORMY16_REL_12 + -- : BFD_RELOC_XSTORMY16_12 + -- : BFD_RELOC_XSTORMY16_24 + -- : BFD_RELOC_XSTORMY16_FPTR16 + Sony Xstormy16 Relocations. + + -- : BFD_RELOC_RELC + Self-describing complex relocations. + + -- : BFD_RELOC_XC16X_PAG + -- : BFD_RELOC_XC16X_POF + -- : BFD_RELOC_XC16X_SEG + -- : BFD_RELOC_XC16X_SOF + Infineon Relocations. + + -- : BFD_RELOC_VAX_GLOB_DAT + -- : BFD_RELOC_VAX_JMP_SLOT + -- : BFD_RELOC_VAX_RELATIVE + Relocations used by VAX ELF. + + -- : BFD_RELOC_MT_PC16 + Morpho MT - 16 bit immediate relocation. + + -- : BFD_RELOC_MT_HI16 + Morpho MT - Hi 16 bits of an address. + + -- : BFD_RELOC_MT_LO16 + Morpho MT - Low 16 bits of an address. + + -- : BFD_RELOC_MT_GNU_VTINHERIT + Morpho MT - Used to tell the linker which vtable entries are used. + + -- : BFD_RELOC_MT_GNU_VTENTRY + Morpho MT - Used to tell the linker which vtable entries are used. + + -- : BFD_RELOC_MT_PCINSN8 + Morpho MT - 8 bit immediate relocation. + + -- : BFD_RELOC_MSP430_10_PCREL + -- : BFD_RELOC_MSP430_16_PCREL + -- : BFD_RELOC_MSP430_16 + -- : BFD_RELOC_MSP430_16_PCREL_BYTE + -- : BFD_RELOC_MSP430_16_BYTE + -- : BFD_RELOC_MSP430_2X_PCREL + -- : BFD_RELOC_MSP430_RL_PCREL + msp430 specific relocation codes + + -- : BFD_RELOC_IQ2000_OFFSET_16 + -- : BFD_RELOC_IQ2000_OFFSET_21 + -- : BFD_RELOC_IQ2000_UHI16 + IQ2000 Relocations. + + -- : BFD_RELOC_XTENSA_RTLD + Special Xtensa relocation used only by PLT entries in ELF shared + objects to indicate that the runtime linker should set the value + to one of its own internal functions or data structures. + + -- : BFD_RELOC_XTENSA_GLOB_DAT + -- : BFD_RELOC_XTENSA_JMP_SLOT + -- : BFD_RELOC_XTENSA_RELATIVE + Xtensa relocations for ELF shared objects. + + -- : BFD_RELOC_XTENSA_PLT + Xtensa relocation used in ELF object files for symbols that may + require PLT entries. Otherwise, this is just a generic 32-bit + relocation. + + -- : BFD_RELOC_XTENSA_DIFF8 + -- : BFD_RELOC_XTENSA_DIFF16 + -- : BFD_RELOC_XTENSA_DIFF32 + Xtensa relocations to mark the difference of two local symbols. + These are only needed to support linker relaxation and can be + ignored when not relaxing. The field is set to the value of the + difference assuming no relaxation. The relocation encodes the + position of the first symbol so the linker can determine whether + to adjust the field value. + + -- : BFD_RELOC_XTENSA_SLOT0_OP + -- : BFD_RELOC_XTENSA_SLOT1_OP + -- : BFD_RELOC_XTENSA_SLOT2_OP + -- : BFD_RELOC_XTENSA_SLOT3_OP + -- : BFD_RELOC_XTENSA_SLOT4_OP + -- : BFD_RELOC_XTENSA_SLOT5_OP + -- : BFD_RELOC_XTENSA_SLOT6_OP + -- : BFD_RELOC_XTENSA_SLOT7_OP + -- : BFD_RELOC_XTENSA_SLOT8_OP + -- : BFD_RELOC_XTENSA_SLOT9_OP + -- : BFD_RELOC_XTENSA_SLOT10_OP + -- : BFD_RELOC_XTENSA_SLOT11_OP + -- : BFD_RELOC_XTENSA_SLOT12_OP + -- : BFD_RELOC_XTENSA_SLOT13_OP + -- : BFD_RELOC_XTENSA_SLOT14_OP + Generic Xtensa relocations for instruction operands. Only the slot + number is encoded in the relocation. The relocation applies to the + last PC-relative immediate operand, or if there are no PC-relative + immediates, to the last immediate operand. + + -- : BFD_RELOC_XTENSA_SLOT0_ALT + -- : BFD_RELOC_XTENSA_SLOT1_ALT + -- : BFD_RELOC_XTENSA_SLOT2_ALT + -- : BFD_RELOC_XTENSA_SLOT3_ALT + -- : BFD_RELOC_XTENSA_SLOT4_ALT + -- : BFD_RELOC_XTENSA_SLOT5_ALT + -- : BFD_RELOC_XTENSA_SLOT6_ALT + -- : BFD_RELOC_XTENSA_SLOT7_ALT + -- : BFD_RELOC_XTENSA_SLOT8_ALT + -- : BFD_RELOC_XTENSA_SLOT9_ALT + -- : BFD_RELOC_XTENSA_SLOT10_ALT + -- : BFD_RELOC_XTENSA_SLOT11_ALT + -- : BFD_RELOC_XTENSA_SLOT12_ALT + -- : BFD_RELOC_XTENSA_SLOT13_ALT + -- : BFD_RELOC_XTENSA_SLOT14_ALT + Alternate Xtensa relocations. Only the slot is encoded in the + relocation. The meaning of these relocations is opcode-specific. + + -- : BFD_RELOC_XTENSA_OP0 + -- : BFD_RELOC_XTENSA_OP1 + -- : BFD_RELOC_XTENSA_OP2 + Xtensa relocations for backward compatibility. These have all been + replaced by BFD_RELOC_XTENSA_SLOT0_OP. + + -- : BFD_RELOC_XTENSA_ASM_EXPAND + Xtensa relocation to mark that the assembler expanded the + instructions from an original target. The expansion size is + encoded in the reloc size. + + -- : BFD_RELOC_XTENSA_ASM_SIMPLIFY + Xtensa relocation to mark that the linker should simplify + assembler-expanded instructions. This is commonly used internally + by the linker after analysis of a BFD_RELOC_XTENSA_ASM_EXPAND. + + -- : BFD_RELOC_XTENSA_TLSDESC_FN + -- : BFD_RELOC_XTENSA_TLSDESC_ARG + -- : BFD_RELOC_XTENSA_TLS_DTPOFF + -- : BFD_RELOC_XTENSA_TLS_TPOFF + -- : BFD_RELOC_XTENSA_TLS_FUNC + -- : BFD_RELOC_XTENSA_TLS_ARG + -- : BFD_RELOC_XTENSA_TLS_CALL + Xtensa TLS relocations. + + -- : BFD_RELOC_Z80_DISP8 + 8 bit signed offset in (ix+d) or (iy+d). + + -- : BFD_RELOC_Z8K_DISP7 + DJNZ offset. + + -- : BFD_RELOC_Z8K_CALLR + CALR offset. + + -- : BFD_RELOC_Z8K_IMM4L + 4 bit value. + + -- : BFD_RELOC_LM32_CALL + -- : BFD_RELOC_LM32_BRANCH + -- : BFD_RELOC_LM32_16_GOT + -- : BFD_RELOC_LM32_GOTOFF_HI16 + -- : BFD_RELOC_LM32_GOTOFF_LO16 + -- : BFD_RELOC_LM32_COPY + -- : BFD_RELOC_LM32_GLOB_DAT + -- : BFD_RELOC_LM32_JMP_SLOT + -- : BFD_RELOC_LM32_RELATIVE + Lattice Mico32 relocations. + + -- : BFD_RELOC_MACH_O_SECTDIFF + Difference between two section addreses. Must be followed by a + BFD_RELOC_MACH_O_PAIR. + + -- : BFD_RELOC_MACH_O_PAIR + Mach-O generic relocations. + + -- : BFD_RELOC_MICROBLAZE_32_LO + This is a 32 bit reloc for the microblaze that stores the low 16 + bits of a value + + -- : BFD_RELOC_MICROBLAZE_32_LO_PCREL + This is a 32 bit pc-relative reloc for the microblaze that stores + the low 16 bits of a value + + -- : BFD_RELOC_MICROBLAZE_32_ROSDA + This is a 32 bit reloc for the microblaze that stores a value + relative to the read-only small data area anchor + + -- : BFD_RELOC_MICROBLAZE_32_RWSDA + This is a 32 bit reloc for the microblaze that stores a value + relative to the read-write small data area anchor + + -- : BFD_RELOC_MICROBLAZE_32_SYM_OP_SYM + This is a 32 bit reloc for the microblaze to handle expressions of + the form "Symbol Op Symbol" + + -- : BFD_RELOC_MICROBLAZE_64_NONE + This is a 64 bit reloc that stores the 32 bit pc relative value in + two words (with an imm instruction). No relocation is done here - + only used for relaxing + + -- : BFD_RELOC_MICROBLAZE_64_GOTPC + This is a 64 bit reloc that stores the 32 bit pc relative value in + two words (with an imm instruction). The relocation is + PC-relative GOT offset + + -- : BFD_RELOC_MICROBLAZE_64_GOT + This is a 64 bit reloc that stores the 32 bit pc relative value in + two words (with an imm instruction). The relocation is GOT offset + + -- : BFD_RELOC_MICROBLAZE_64_PLT + This is a 64 bit reloc that stores the 32 bit pc relative value in + two words (with an imm instruction). The relocation is + PC-relative offset into PLT + + -- : BFD_RELOC_MICROBLAZE_64_GOTOFF + This is a 64 bit reloc that stores the 32 bit GOT relative value + in two words (with an imm instruction). The relocation is + relative offset from _GLOBAL_OFFSET_TABLE_ + + -- : BFD_RELOC_MICROBLAZE_32_GOTOFF + This is a 32 bit reloc that stores the 32 bit GOT relative value + in a word. The relocation is relative offset from + + -- : BFD_RELOC_MICROBLAZE_COPY + This is used to tell the dynamic linker to copy the value out of + the dynamic object into the runtime process image. + + + typedef enum bfd_reloc_code_real bfd_reloc_code_real_type; + +2.10.2.2 `bfd_reloc_type_lookup' +................................ + +*Synopsis* + reloc_howto_type *bfd_reloc_type_lookup + (bfd *abfd, bfd_reloc_code_real_type code); + reloc_howto_type *bfd_reloc_name_lookup + (bfd *abfd, const char *reloc_name); + *Description* +Return a pointer to a howto structure which, when invoked, will perform +the relocation CODE on data from the architecture noted. + +2.10.2.3 `bfd_default_reloc_type_lookup' +........................................ + +*Synopsis* + reloc_howto_type *bfd_default_reloc_type_lookup + (bfd *abfd, bfd_reloc_code_real_type code); + *Description* +Provides a default relocation lookup routine for any architecture. + +2.10.2.4 `bfd_get_reloc_code_name' +.................................. + +*Synopsis* + const char *bfd_get_reloc_code_name (bfd_reloc_code_real_type code); + *Description* +Provides a printable name for the supplied relocation code. Useful +mainly for printing error messages. + +2.10.2.5 `bfd_generic_relax_section' +.................................... + +*Synopsis* + bfd_boolean bfd_generic_relax_section + (bfd *abfd, + asection *section, + struct bfd_link_info *, + bfd_boolean *); + *Description* +Provides default handling for relaxing for back ends which don't do +relaxing. + +2.10.2.6 `bfd_generic_gc_sections' +.................................. + +*Synopsis* + bfd_boolean bfd_generic_gc_sections + (bfd *, struct bfd_link_info *); + *Description* +Provides default handling for relaxing for back ends which don't do +section gc - i.e., does nothing. + +2.10.2.7 `bfd_generic_merge_sections' +..................................... + +*Synopsis* + bfd_boolean bfd_generic_merge_sections + (bfd *, struct bfd_link_info *); + *Description* +Provides default handling for SEC_MERGE section merging for back ends +which don't have SEC_MERGE support - i.e., does nothing. + +2.10.2.8 `bfd_generic_get_relocated_section_contents' +..................................................... + +*Synopsis* + bfd_byte *bfd_generic_get_relocated_section_contents + (bfd *abfd, + struct bfd_link_info *link_info, + struct bfd_link_order *link_order, + bfd_byte *data, + bfd_boolean relocatable, + asymbol **symbols); + *Description* +Provides default handling of relocation effort for back ends which +can't be bothered to do it efficiently. + + +File: bfd.info, Node: Core Files, Next: Targets, Prev: Relocations, Up: BFD front end + +2.11 Core files +=============== + +2.11.1 Core file functions +-------------------------- + +*Description* +These are functions pertaining to core files. + +2.11.1.1 `bfd_core_file_failing_command' +........................................ + +*Synopsis* + const char *bfd_core_file_failing_command (bfd *abfd); + *Description* +Return a read-only string explaining which program was running when it +failed and produced the core file ABFD. + +2.11.1.2 `bfd_core_file_failing_signal' +....................................... + +*Synopsis* + int bfd_core_file_failing_signal (bfd *abfd); + *Description* +Returns the signal number which caused the core dump which generated +the file the BFD ABFD is attached to. + +2.11.1.3 `core_file_matches_executable_p' +......................................... + +*Synopsis* + bfd_boolean core_file_matches_executable_p + (bfd *core_bfd, bfd *exec_bfd); + *Description* +Return `TRUE' if the core file attached to CORE_BFD was generated by a +run of the executable file attached to EXEC_BFD, `FALSE' otherwise. + +2.11.1.4 `generic_core_file_matches_executable_p' +................................................. + +*Synopsis* + bfd_boolean generic_core_file_matches_executable_p + (bfd *core_bfd, bfd *exec_bfd); + *Description* +Return TRUE if the core file attached to CORE_BFD was generated by a +run of the executable file attached to EXEC_BFD. The match is based on +executable basenames only. + + Note: When not able to determine the core file failing command or +the executable name, we still return TRUE even though we're not sure +that core file and executable match. This is to avoid generating a +false warning in situations where we really don't know whether they +match or not. + + +File: bfd.info, Node: Targets, Next: Architectures, Prev: Core Files, Up: BFD front end + +2.12 Targets +============ + +*Description* +Each port of BFD to a different machine requires the creation of a +target back end. All the back end provides to the root part of BFD is a +structure containing pointers to functions which perform certain low +level operations on files. BFD translates the applications's requests +through a pointer into calls to the back end routines. + + When a file is opened with `bfd_openr', its format and target are +unknown. BFD uses various mechanisms to determine how to interpret the +file. The operations performed are: + + * Create a BFD by calling the internal routine `_bfd_new_bfd', then + call `bfd_find_target' with the target string supplied to + `bfd_openr' and the new BFD pointer. + + * If a null target string was provided to `bfd_find_target', look up + the environment variable `GNUTARGET' and use that as the target + string. + + * If the target string is still `NULL', or the target string is + `default', then use the first item in the target vector as the + target type, and set `target_defaulted' in the BFD to cause + `bfd_check_format' to loop through all the targets. *Note + bfd_target::. *Note Formats::. + + * Otherwise, inspect the elements in the target vector one by one, + until a match on target name is found. When found, use it. + + * Otherwise return the error `bfd_error_invalid_target' to + `bfd_openr'. + + * `bfd_openr' attempts to open the file using `bfd_open_file', and + returns the BFD. + Once the BFD has been opened and the target selected, the file +format may be determined. This is done by calling `bfd_check_format' on +the BFD with a suggested format. If `target_defaulted' has been set, +each possible target type is tried to see if it recognizes the +specified format. `bfd_check_format' returns `TRUE' when the caller +guesses right. + +* Menu: + +* bfd_target:: + + +File: bfd.info, Node: bfd_target, Prev: Targets, Up: Targets + +2.12.1 bfd_target +----------------- + +*Description* +This structure contains everything that BFD knows about a target. It +includes things like its byte order, name, and which routines to call +to do various operations. + + Every BFD points to a target structure with its `xvec' member. + + The macros below are used to dispatch to functions through the +`bfd_target' vector. They are used in a number of macros further down +in `bfd.h', and are also used when calling various routines by hand +inside the BFD implementation. The ARGLIST argument must be +parenthesized; it contains all the arguments to the called function. + + They make the documentation (more) unpleasant to read, so if someone +wants to fix this and not break the above, please do. + #define BFD_SEND(bfd, message, arglist) \ + ((*((bfd)->xvec->message)) arglist) + + #ifdef DEBUG_BFD_SEND + #undef BFD_SEND + #define BFD_SEND(bfd, message, arglist) \ + (((bfd) && (bfd)->xvec && (bfd)->xvec->message) ? \ + ((*((bfd)->xvec->message)) arglist) : \ + (bfd_assert (__FILE__,__LINE__), NULL)) + #endif + For operations which index on the BFD format: + #define BFD_SEND_FMT(bfd, message, arglist) \ + (((bfd)->xvec->message[(int) ((bfd)->format)]) arglist) + + #ifdef DEBUG_BFD_SEND + #undef BFD_SEND_FMT + #define BFD_SEND_FMT(bfd, message, arglist) \ + (((bfd) && (bfd)->xvec && (bfd)->xvec->message) ? \ + (((bfd)->xvec->message[(int) ((bfd)->format)]) arglist) : \ + (bfd_assert (__FILE__,__LINE__), NULL)) + #endif + This is the structure which defines the type of BFD this is. The +`xvec' member of the struct `bfd' itself points here. Each module that +implements access to a different target under BFD, defines one of these. + + FIXME, these names should be rationalised with the names of the +entry points which call them. Too bad we can't have one macro to define +them both! + enum bfd_flavour + { + bfd_target_unknown_flavour, + bfd_target_aout_flavour, + bfd_target_coff_flavour, + bfd_target_ecoff_flavour, + bfd_target_xcoff_flavour, + bfd_target_elf_flavour, + bfd_target_ieee_flavour, + bfd_target_nlm_flavour, + bfd_target_oasys_flavour, + bfd_target_tekhex_flavour, + bfd_target_srec_flavour, + bfd_target_verilog_flavour, + bfd_target_ihex_flavour, + bfd_target_som_flavour, + bfd_target_os9k_flavour, + bfd_target_versados_flavour, + bfd_target_msdos_flavour, + bfd_target_ovax_flavour, + bfd_target_evax_flavour, + bfd_target_mmo_flavour, + bfd_target_mach_o_flavour, + bfd_target_pef_flavour, + bfd_target_pef_xlib_flavour, + bfd_target_sym_flavour + }; + + enum bfd_endian { BFD_ENDIAN_BIG, BFD_ENDIAN_LITTLE, BFD_ENDIAN_UNKNOWN }; + + /* Forward declaration. */ + typedef struct bfd_link_info _bfd_link_info; + + typedef struct bfd_target + { + /* Identifies the kind of target, e.g., SunOS4, Ultrix, etc. */ + char *name; + + /* The "flavour" of a back end is a general indication about + the contents of a file. */ + enum bfd_flavour flavour; + + /* The order of bytes within the data area of a file. */ + enum bfd_endian byteorder; + + /* The order of bytes within the header parts of a file. */ + enum bfd_endian header_byteorder; + + /* A mask of all the flags which an executable may have set - + from the set `BFD_NO_FLAGS', `HAS_RELOC', ...`D_PAGED'. */ + flagword object_flags; + + /* A mask of all the flags which a section may have set - from + the set `SEC_NO_FLAGS', `SEC_ALLOC', ...`SET_NEVER_LOAD'. */ + flagword section_flags; + + /* The character normally found at the front of a symbol. + (if any), perhaps `_'. */ + char symbol_leading_char; + + /* The pad character for file names within an archive header. */ + char ar_pad_char; + + /* The maximum number of characters in an archive header. */ + unsigned short ar_max_namelen; + + /* Entries for byte swapping for data. These are different from the + other entry points, since they don't take a BFD as the first argument. + Certain other handlers could do the same. */ + bfd_uint64_t (*bfd_getx64) (const void *); + bfd_int64_t (*bfd_getx_signed_64) (const void *); + void (*bfd_putx64) (bfd_uint64_t, void *); + bfd_vma (*bfd_getx32) (const void *); + bfd_signed_vma (*bfd_getx_signed_32) (const void *); + void (*bfd_putx32) (bfd_vma, void *); + bfd_vma (*bfd_getx16) (const void *); + bfd_signed_vma (*bfd_getx_signed_16) (const void *); + void (*bfd_putx16) (bfd_vma, void *); + + /* Byte swapping for the headers. */ + bfd_uint64_t (*bfd_h_getx64) (const void *); + bfd_int64_t (*bfd_h_getx_signed_64) (const void *); + void (*bfd_h_putx64) (bfd_uint64_t, void *); + bfd_vma (*bfd_h_getx32) (const void *); + bfd_signed_vma (*bfd_h_getx_signed_32) (const void *); + void (*bfd_h_putx32) (bfd_vma, void *); + bfd_vma (*bfd_h_getx16) (const void *); + bfd_signed_vma (*bfd_h_getx_signed_16) (const void *); + void (*bfd_h_putx16) (bfd_vma, void *); + + /* Format dependent routines: these are vectors of entry points + within the target vector structure, one for each format to check. */ + + /* Check the format of a file being read. Return a `bfd_target *' or zero. */ + const struct bfd_target *(*_bfd_check_format[bfd_type_end]) (bfd *); + + /* Set the format of a file being written. */ + bfd_boolean (*_bfd_set_format[bfd_type_end]) (bfd *); + + /* Write cached information into a file being written, at `bfd_close'. */ + bfd_boolean (*_bfd_write_contents[bfd_type_end]) (bfd *); + The general target vector. These vectors are initialized using the +BFD_JUMP_TABLE macros. + + /* Generic entry points. */ + #define BFD_JUMP_TABLE_GENERIC(NAME) \ + NAME##_close_and_cleanup, \ + NAME##_bfd_free_cached_info, \ + NAME##_new_section_hook, \ + NAME##_get_section_contents, \ + NAME##_get_section_contents_in_window + + /* Called when the BFD is being closed to do any necessary cleanup. */ + bfd_boolean (*_close_and_cleanup) (bfd *); + /* Ask the BFD to free all cached information. */ + bfd_boolean (*_bfd_free_cached_info) (bfd *); + /* Called when a new section is created. */ + bfd_boolean (*_new_section_hook) (bfd *, sec_ptr); + /* Read the contents of a section. */ + bfd_boolean (*_bfd_get_section_contents) + (bfd *, sec_ptr, void *, file_ptr, bfd_size_type); + bfd_boolean (*_bfd_get_section_contents_in_window) + (bfd *, sec_ptr, bfd_window *, file_ptr, bfd_size_type); + + /* Entry points to copy private data. */ + #define BFD_JUMP_TABLE_COPY(NAME) \ + NAME##_bfd_copy_private_bfd_data, \ + NAME##_bfd_merge_private_bfd_data, \ + _bfd_generic_init_private_section_data, \ + NAME##_bfd_copy_private_section_data, \ + NAME##_bfd_copy_private_symbol_data, \ + NAME##_bfd_copy_private_header_data, \ + NAME##_bfd_set_private_flags, \ + NAME##_bfd_print_private_bfd_data + + /* Called to copy BFD general private data from one object file + to another. */ + bfd_boolean (*_bfd_copy_private_bfd_data) (bfd *, bfd *); + /* Called to merge BFD general private data from one object file + to a common output file when linking. */ + bfd_boolean (*_bfd_merge_private_bfd_data) (bfd *, bfd *); + /* Called to initialize BFD private section data from one object file + to another. */ + #define bfd_init_private_section_data(ibfd, isec, obfd, osec, link_info) \ + BFD_SEND (obfd, _bfd_init_private_section_data, (ibfd, isec, obfd, osec, link_info)) + bfd_boolean (*_bfd_init_private_section_data) + (bfd *, sec_ptr, bfd *, sec_ptr, struct bfd_link_info *); + /* Called to copy BFD private section data from one object file + to another. */ + bfd_boolean (*_bfd_copy_private_section_data) + (bfd *, sec_ptr, bfd *, sec_ptr); + /* Called to copy BFD private symbol data from one symbol + to another. */ + bfd_boolean (*_bfd_copy_private_symbol_data) + (bfd *, asymbol *, bfd *, asymbol *); + /* Called to copy BFD private header data from one object file + to another. */ + bfd_boolean (*_bfd_copy_private_header_data) + (bfd *, bfd *); + /* Called to set private backend flags. */ + bfd_boolean (*_bfd_set_private_flags) (bfd *, flagword); + + /* Called to print private BFD data. */ + bfd_boolean (*_bfd_print_private_bfd_data) (bfd *, void *); + + /* Core file entry points. */ + #define BFD_JUMP_TABLE_CORE(NAME) \ + NAME##_core_file_failing_command, \ + NAME##_core_file_failing_signal, \ + NAME##_core_file_matches_executable_p + + char * (*_core_file_failing_command) (bfd *); + int (*_core_file_failing_signal) (bfd *); + bfd_boolean (*_core_file_matches_executable_p) (bfd *, bfd *); + + /* Archive entry points. */ + #define BFD_JUMP_TABLE_ARCHIVE(NAME) \ + NAME##_slurp_armap, \ + NAME##_slurp_extended_name_table, \ + NAME##_construct_extended_name_table, \ + NAME##_truncate_arname, \ + NAME##_write_armap, \ + NAME##_read_ar_hdr, \ + NAME##_openr_next_archived_file, \ + NAME##_get_elt_at_index, \ + NAME##_generic_stat_arch_elt, \ + NAME##_update_armap_timestamp + + bfd_boolean (*_bfd_slurp_armap) (bfd *); + bfd_boolean (*_bfd_slurp_extended_name_table) (bfd *); + bfd_boolean (*_bfd_construct_extended_name_table) + (bfd *, char **, bfd_size_type *, const char **); + void (*_bfd_truncate_arname) (bfd *, const char *, char *); + bfd_boolean (*write_armap) + (bfd *, unsigned int, struct orl *, unsigned int, int); + void * (*_bfd_read_ar_hdr_fn) (bfd *); + bfd * (*openr_next_archived_file) (bfd *, bfd *); + #define bfd_get_elt_at_index(b,i) BFD_SEND (b, _bfd_get_elt_at_index, (b,i)) + bfd * (*_bfd_get_elt_at_index) (bfd *, symindex); + int (*_bfd_stat_arch_elt) (bfd *, struct stat *); + bfd_boolean (*_bfd_update_armap_timestamp) (bfd *); + + /* Entry points used for symbols. */ + #define BFD_JUMP_TABLE_SYMBOLS(NAME) \ + NAME##_get_symtab_upper_bound, \ + NAME##_canonicalize_symtab, \ + NAME##_make_empty_symbol, \ + NAME##_print_symbol, \ + NAME##_get_symbol_info, \ + NAME##_bfd_is_local_label_name, \ + NAME##_bfd_is_target_special_symbol, \ + NAME##_get_lineno, \ + NAME##_find_nearest_line, \ + _bfd_generic_find_line, \ + NAME##_find_inliner_info, \ + NAME##_bfd_make_debug_symbol, \ + NAME##_read_minisymbols, \ + NAME##_minisymbol_to_symbol + + long (*_bfd_get_symtab_upper_bound) (bfd *); + long (*_bfd_canonicalize_symtab) + (bfd *, struct bfd_symbol **); + struct bfd_symbol * + (*_bfd_make_empty_symbol) (bfd *); + void (*_bfd_print_symbol) + (bfd *, void *, struct bfd_symbol *, bfd_print_symbol_type); + #define bfd_print_symbol(b,p,s,e) BFD_SEND (b, _bfd_print_symbol, (b,p,s,e)) + void (*_bfd_get_symbol_info) + (bfd *, struct bfd_symbol *, symbol_info *); + #define bfd_get_symbol_info(b,p,e) BFD_SEND (b, _bfd_get_symbol_info, (b,p,e)) + bfd_boolean (*_bfd_is_local_label_name) (bfd *, const char *); + bfd_boolean (*_bfd_is_target_special_symbol) (bfd *, asymbol *); + alent * (*_get_lineno) (bfd *, struct bfd_symbol *); + bfd_boolean (*_bfd_find_nearest_line) + (bfd *, struct bfd_section *, struct bfd_symbol **, bfd_vma, + const char **, const char **, unsigned int *); + bfd_boolean (*_bfd_find_line) + (bfd *, struct bfd_symbol **, struct bfd_symbol *, + const char **, unsigned int *); + bfd_boolean (*_bfd_find_inliner_info) + (bfd *, const char **, const char **, unsigned int *); + /* Back-door to allow format-aware applications to create debug symbols + while using BFD for everything else. Currently used by the assembler + when creating COFF files. */ + asymbol * (*_bfd_make_debug_symbol) + (bfd *, void *, unsigned long size); + #define bfd_read_minisymbols(b, d, m, s) \ + BFD_SEND (b, _read_minisymbols, (b, d, m, s)) + long (*_read_minisymbols) + (bfd *, bfd_boolean, void **, unsigned int *); + #define bfd_minisymbol_to_symbol(b, d, m, f) \ + BFD_SEND (b, _minisymbol_to_symbol, (b, d, m, f)) + asymbol * (*_minisymbol_to_symbol) + (bfd *, bfd_boolean, const void *, asymbol *); + + /* Routines for relocs. */ + #define BFD_JUMP_TABLE_RELOCS(NAME) \ + NAME##_get_reloc_upper_bound, \ + NAME##_canonicalize_reloc, \ + NAME##_bfd_reloc_type_lookup, \ + NAME##_bfd_reloc_name_lookup + + long (*_get_reloc_upper_bound) (bfd *, sec_ptr); + long (*_bfd_canonicalize_reloc) + (bfd *, sec_ptr, arelent **, struct bfd_symbol **); + /* See documentation on reloc types. */ + reloc_howto_type * + (*reloc_type_lookup) (bfd *, bfd_reloc_code_real_type); + reloc_howto_type * + (*reloc_name_lookup) (bfd *, const char *); + + + /* Routines used when writing an object file. */ + #define BFD_JUMP_TABLE_WRITE(NAME) \ + NAME##_set_arch_mach, \ + NAME##_set_section_contents + + bfd_boolean (*_bfd_set_arch_mach) + (bfd *, enum bfd_architecture, unsigned long); + bfd_boolean (*_bfd_set_section_contents) + (bfd *, sec_ptr, const void *, file_ptr, bfd_size_type); + + /* Routines used by the linker. */ + #define BFD_JUMP_TABLE_LINK(NAME) \ + NAME##_sizeof_headers, \ + NAME##_bfd_get_relocated_section_contents, \ + NAME##_bfd_relax_section, \ + NAME##_bfd_link_hash_table_create, \ + NAME##_bfd_link_hash_table_free, \ + NAME##_bfd_link_add_symbols, \ + NAME##_bfd_link_just_syms, \ + NAME##_bfd_final_link, \ + NAME##_bfd_link_split_section, \ + NAME##_bfd_gc_sections, \ + NAME##_bfd_merge_sections, \ + NAME##_bfd_is_group_section, \ + NAME##_bfd_discard_group, \ + NAME##_section_already_linked, \ + NAME##_bfd_define_common_symbol + + int (*_bfd_sizeof_headers) (bfd *, struct bfd_link_info *); + bfd_byte * (*_bfd_get_relocated_section_contents) + (bfd *, struct bfd_link_info *, struct bfd_link_order *, + bfd_byte *, bfd_boolean, struct bfd_symbol **); + + bfd_boolean (*_bfd_relax_section) + (bfd *, struct bfd_section *, struct bfd_link_info *, bfd_boolean *); + + /* Create a hash table for the linker. Different backends store + different information in this table. */ + struct bfd_link_hash_table * + (*_bfd_link_hash_table_create) (bfd *); + + /* Release the memory associated with the linker hash table. */ + void (*_bfd_link_hash_table_free) (struct bfd_link_hash_table *); + + /* Add symbols from this object file into the hash table. */ + bfd_boolean (*_bfd_link_add_symbols) (bfd *, struct bfd_link_info *); + + /* Indicate that we are only retrieving symbol values from this section. */ + void (*_bfd_link_just_syms) (asection *, struct bfd_link_info *); + + /* Do a link based on the link_order structures attached to each + section of the BFD. */ + bfd_boolean (*_bfd_final_link) (bfd *, struct bfd_link_info *); + + /* Should this section be split up into smaller pieces during linking. */ + bfd_boolean (*_bfd_link_split_section) (bfd *, struct bfd_section *); + + /* Remove sections that are not referenced from the output. */ + bfd_boolean (*_bfd_gc_sections) (bfd *, struct bfd_link_info *); + + /* Attempt to merge SEC_MERGE sections. */ + bfd_boolean (*_bfd_merge_sections) (bfd *, struct bfd_link_info *); + + /* Is this section a member of a group? */ + bfd_boolean (*_bfd_is_group_section) (bfd *, const struct bfd_section *); + + /* Discard members of a group. */ + bfd_boolean (*_bfd_discard_group) (bfd *, struct bfd_section *); + + /* Check if SEC has been already linked during a reloceatable or + final link. */ + void (*_section_already_linked) (bfd *, struct bfd_section *, + struct bfd_link_info *); + + /* Define a common symbol. */ + bfd_boolean (*_bfd_define_common_symbol) (bfd *, struct bfd_link_info *, + struct bfd_link_hash_entry *); + + /* Routines to handle dynamic symbols and relocs. */ + #define BFD_JUMP_TABLE_DYNAMIC(NAME) \ + NAME##_get_dynamic_symtab_upper_bound, \ + NAME##_canonicalize_dynamic_symtab, \ + NAME##_get_synthetic_symtab, \ + NAME##_get_dynamic_reloc_upper_bound, \ + NAME##_canonicalize_dynamic_reloc + + /* Get the amount of memory required to hold the dynamic symbols. */ + long (*_bfd_get_dynamic_symtab_upper_bound) (bfd *); + /* Read in the dynamic symbols. */ + long (*_bfd_canonicalize_dynamic_symtab) + (bfd *, struct bfd_symbol **); + /* Create synthetized symbols. */ + long (*_bfd_get_synthetic_symtab) + (bfd *, long, struct bfd_symbol **, long, struct bfd_symbol **, + struct bfd_symbol **); + /* Get the amount of memory required to hold the dynamic relocs. */ + long (*_bfd_get_dynamic_reloc_upper_bound) (bfd *); + /* Read in the dynamic relocs. */ + long (*_bfd_canonicalize_dynamic_reloc) + (bfd *, arelent **, struct bfd_symbol **); + A pointer to an alternative bfd_target in case the current one is not +satisfactory. This can happen when the target cpu supports both big +and little endian code, and target chosen by the linker has the wrong +endianness. The function open_output() in ld/ldlang.c uses this field +to find an alternative output format that is suitable. + /* Opposite endian version of this target. */ + const struct bfd_target * alternative_target; + + /* Data for use by back-end routines, which isn't + generic enough to belong in this structure. */ + const void *backend_data; + + } bfd_target; + +2.12.1.1 `bfd_set_default_target' +................................. + +*Synopsis* + bfd_boolean bfd_set_default_target (const char *name); + *Description* +Set the default target vector to use when recognizing a BFD. This +takes the name of the target, which may be a BFD target name or a +configuration triplet. + +2.12.1.2 `bfd_find_target' +.......................... + +*Synopsis* + const bfd_target *bfd_find_target (const char *target_name, bfd *abfd); + *Description* +Return a pointer to the transfer vector for the object target named +TARGET_NAME. If TARGET_NAME is `NULL', choose the one in the +environment variable `GNUTARGET'; if that is null or not defined, then +choose the first entry in the target list. Passing in the string +"default" or setting the environment variable to "default" will cause +the first entry in the target list to be returned, and +"target_defaulted" will be set in the BFD if ABFD isn't `NULL'. This +causes `bfd_check_format' to loop over all the targets to find the one +that matches the file being read. + +2.12.1.3 `bfd_target_list' +.......................... + +*Synopsis* + const char ** bfd_target_list (void); + *Description* +Return a freshly malloced NULL-terminated vector of the names of all +the valid BFD targets. Do not modify the names. + +2.12.1.4 `bfd_seach_for_target' +............................... + +*Synopsis* + const bfd_target *bfd_search_for_target + (int (*search_func) (const bfd_target *, void *), + void *); + *Description* +Return a pointer to the first transfer vector in the list of transfer +vectors maintained by BFD that produces a non-zero result when passed +to the function SEARCH_FUNC. The parameter DATA is passed, unexamined, +to the search function. + + +File: bfd.info, Node: Architectures, Next: Opening and Closing, Prev: Targets, Up: BFD front end + +2.13 Architectures +================== + +BFD keeps one atom in a BFD describing the architecture of the data +attached to the BFD: a pointer to a `bfd_arch_info_type'. + + Pointers to structures can be requested independently of a BFD so +that an architecture's information can be interrogated without access +to an open BFD. + + The architecture information is provided by each architecture +package. The set of default architectures is selected by the macro +`SELECT_ARCHITECTURES'. This is normally set up in the +`config/TARGET.mt' file of your choice. If the name is not defined, +then all the architectures supported are included. + + When BFD starts up, all the architectures are called with an +initialize method. It is up to the architecture back end to insert as +many items into the list of architectures as it wants to; generally +this would be one for each machine and one for the default case (an +item with a machine field of 0). + + BFD's idea of an architecture is implemented in `archures.c'. + +2.13.1 bfd_architecture +----------------------- + +*Description* +This enum gives the object file's CPU architecture, in a global +sense--i.e., what processor family does it belong to? Another field +indicates which processor within the family is in use. The machine +gives a number which distinguishes different versions of the +architecture, containing, for example, 2 and 3 for Intel i960 KA and +i960 KB, and 68020 and 68030 for Motorola 68020 and 68030. + enum bfd_architecture + { + bfd_arch_unknown, /* File arch not known. */ + bfd_arch_obscure, /* Arch known, not one of these. */ + bfd_arch_m68k, /* Motorola 68xxx */ + #define bfd_mach_m68000 1 + #define bfd_mach_m68008 2 + #define bfd_mach_m68010 3 + #define bfd_mach_m68020 4 + #define bfd_mach_m68030 5 + #define bfd_mach_m68040 6 + #define bfd_mach_m68060 7 + #define bfd_mach_cpu32 8 + #define bfd_mach_fido 9 + #define bfd_mach_mcf_isa_a_nodiv 10 + #define bfd_mach_mcf_isa_a 11 + #define bfd_mach_mcf_isa_a_mac 12 + #define bfd_mach_mcf_isa_a_emac 13 + #define bfd_mach_mcf_isa_aplus 14 + #define bfd_mach_mcf_isa_aplus_mac 15 + #define bfd_mach_mcf_isa_aplus_emac 16 + #define bfd_mach_mcf_isa_b_nousp 17 + #define bfd_mach_mcf_isa_b_nousp_mac 18 + #define bfd_mach_mcf_isa_b_nousp_emac 19 + #define bfd_mach_mcf_isa_b 20 + #define bfd_mach_mcf_isa_b_mac 21 + #define bfd_mach_mcf_isa_b_emac 22 + #define bfd_mach_mcf_isa_b_float 23 + #define bfd_mach_mcf_isa_b_float_mac 24 + #define bfd_mach_mcf_isa_b_float_emac 25 + #define bfd_mach_mcf_isa_c 26 + #define bfd_mach_mcf_isa_c_mac 27 + #define bfd_mach_mcf_isa_c_emac 28 + #define bfd_mach_mcf_isa_c_nodiv 29 + #define bfd_mach_mcf_isa_c_nodiv_mac 30 + #define bfd_mach_mcf_isa_c_nodiv_emac 31 + bfd_arch_vax, /* DEC Vax */ + bfd_arch_i960, /* Intel 960 */ + /* The order of the following is important. + lower number indicates a machine type that + only accepts a subset of the instructions + available to machines with higher numbers. + The exception is the "ca", which is + incompatible with all other machines except + "core". */ + + #define bfd_mach_i960_core 1 + #define bfd_mach_i960_ka_sa 2 + #define bfd_mach_i960_kb_sb 3 + #define bfd_mach_i960_mc 4 + #define bfd_mach_i960_xa 5 + #define bfd_mach_i960_ca 6 + #define bfd_mach_i960_jx 7 + #define bfd_mach_i960_hx 8 + + bfd_arch_or32, /* OpenRISC 32 */ + + bfd_arch_sparc, /* SPARC */ + #define bfd_mach_sparc 1 + /* The difference between v8plus and v9 is that v9 is a true 64 bit env. */ + #define bfd_mach_sparc_sparclet 2 + #define bfd_mach_sparc_sparclite 3 + #define bfd_mach_sparc_v8plus 4 + #define bfd_mach_sparc_v8plusa 5 /* with ultrasparc add'ns. */ + #define bfd_mach_sparc_sparclite_le 6 + #define bfd_mach_sparc_v9 7 + #define bfd_mach_sparc_v9a 8 /* with ultrasparc add'ns. */ + #define bfd_mach_sparc_v8plusb 9 /* with cheetah add'ns. */ + #define bfd_mach_sparc_v9b 10 /* with cheetah add'ns. */ + /* Nonzero if MACH has the v9 instruction set. */ + #define bfd_mach_sparc_v9_p(mach) \ + ((mach) >= bfd_mach_sparc_v8plus && (mach) <= bfd_mach_sparc_v9b \ + && (mach) != bfd_mach_sparc_sparclite_le) + /* Nonzero if MACH is a 64 bit sparc architecture. */ + #define bfd_mach_sparc_64bit_p(mach) \ + ((mach) >= bfd_mach_sparc_v9 && (mach) != bfd_mach_sparc_v8plusb) + bfd_arch_spu, /* PowerPC SPU */ + #define bfd_mach_spu 256 + bfd_arch_mips, /* MIPS Rxxxx */ + #define bfd_mach_mips3000 3000 + #define bfd_mach_mips3900 3900 + #define bfd_mach_mips4000 4000 + #define bfd_mach_mips4010 4010 + #define bfd_mach_mips4100 4100 + #define bfd_mach_mips4111 4111 + #define bfd_mach_mips4120 4120 + #define bfd_mach_mips4300 4300 + #define bfd_mach_mips4400 4400 + #define bfd_mach_mips4600 4600 + #define bfd_mach_mips4650 4650 + #define bfd_mach_mips5000 5000 + #define bfd_mach_mips5400 5400 + #define bfd_mach_mips5500 5500 + #define bfd_mach_mips6000 6000 + #define bfd_mach_mips7000 7000 + #define bfd_mach_mips8000 8000 + #define bfd_mach_mips9000 9000 + #define bfd_mach_mips10000 10000 + #define bfd_mach_mips12000 12000 + #define bfd_mach_mips14000 14000 + #define bfd_mach_mips16000 16000 + #define bfd_mach_mips16 16 + #define bfd_mach_mips5 5 + #define bfd_mach_mips_loongson_2e 3001 + #define bfd_mach_mips_loongson_2f 3002 + #define bfd_mach_mips_sb1 12310201 /* octal 'SB', 01 */ + #define bfd_mach_mips_octeon 6501 + #define bfd_mach_mips_xlr 887682 /* decimal 'XLR' */ + #define bfd_mach_mipsisa32 32 + #define bfd_mach_mipsisa32r2 33 + #define bfd_mach_mipsisa64 64 + #define bfd_mach_mipsisa64r2 65 + bfd_arch_i386, /* Intel 386 */ + #define bfd_mach_i386_i386 1 + #define bfd_mach_i386_i8086 2 + #define bfd_mach_i386_i386_intel_syntax 3 + #define bfd_mach_x86_64 64 + #define bfd_mach_x86_64_intel_syntax 65 + bfd_arch_l1om, /* Intel L1OM */ + #define bfd_mach_l1om 66 + #define bfd_mach_l1om_intel_syntax 67 + bfd_arch_we32k, /* AT&T WE32xxx */ + bfd_arch_tahoe, /* CCI/Harris Tahoe */ + bfd_arch_i860, /* Intel 860 */ + bfd_arch_i370, /* IBM 360/370 Mainframes */ + bfd_arch_romp, /* IBM ROMP PC/RT */ + bfd_arch_convex, /* Convex */ + bfd_arch_m88k, /* Motorola 88xxx */ + bfd_arch_m98k, /* Motorola 98xxx */ + bfd_arch_pyramid, /* Pyramid Technology */ + bfd_arch_h8300, /* Renesas H8/300 (formerly Hitachi H8/300) */ + #define bfd_mach_h8300 1 + #define bfd_mach_h8300h 2 + #define bfd_mach_h8300s 3 + #define bfd_mach_h8300hn 4 + #define bfd_mach_h8300sn 5 + #define bfd_mach_h8300sx 6 + #define bfd_mach_h8300sxn 7 + bfd_arch_pdp11, /* DEC PDP-11 */ + bfd_arch_plugin, + bfd_arch_powerpc, /* PowerPC */ + #define bfd_mach_ppc 32 + #define bfd_mach_ppc64 64 + #define bfd_mach_ppc_403 403 + #define bfd_mach_ppc_403gc 4030 + #define bfd_mach_ppc_405 405 + #define bfd_mach_ppc_505 505 + #define bfd_mach_ppc_601 601 + #define bfd_mach_ppc_602 602 + #define bfd_mach_ppc_603 603 + #define bfd_mach_ppc_ec603e 6031 + #define bfd_mach_ppc_604 604 + #define bfd_mach_ppc_620 620 + #define bfd_mach_ppc_630 630 + #define bfd_mach_ppc_750 750 + #define bfd_mach_ppc_860 860 + #define bfd_mach_ppc_a35 35 + #define bfd_mach_ppc_rs64ii 642 + #define bfd_mach_ppc_rs64iii 643 + #define bfd_mach_ppc_7400 7400 + #define bfd_mach_ppc_e500 500 + #define bfd_mach_ppc_e500mc 5001 + bfd_arch_rs6000, /* IBM RS/6000 */ + #define bfd_mach_rs6k 6000 + #define bfd_mach_rs6k_rs1 6001 + #define bfd_mach_rs6k_rsc 6003 + #define bfd_mach_rs6k_rs2 6002 + bfd_arch_hppa, /* HP PA RISC */ + #define bfd_mach_hppa10 10 + #define bfd_mach_hppa11 11 + #define bfd_mach_hppa20 20 + #define bfd_mach_hppa20w 25 + bfd_arch_d10v, /* Mitsubishi D10V */ + #define bfd_mach_d10v 1 + #define bfd_mach_d10v_ts2 2 + #define bfd_mach_d10v_ts3 3 + bfd_arch_d30v, /* Mitsubishi D30V */ + bfd_arch_dlx, /* DLX */ + bfd_arch_m68hc11, /* Motorola 68HC11 */ + bfd_arch_m68hc12, /* Motorola 68HC12 */ + #define bfd_mach_m6812_default 0 + #define bfd_mach_m6812 1 + #define bfd_mach_m6812s 2 + bfd_arch_z8k, /* Zilog Z8000 */ + #define bfd_mach_z8001 1 + #define bfd_mach_z8002 2 + bfd_arch_h8500, /* Renesas H8/500 (formerly Hitachi H8/500) */ + bfd_arch_sh, /* Renesas / SuperH SH (formerly Hitachi SH) */ + #define bfd_mach_sh 1 + #define bfd_mach_sh2 0x20 + #define bfd_mach_sh_dsp 0x2d + #define bfd_mach_sh2a 0x2a + #define bfd_mach_sh2a_nofpu 0x2b + #define bfd_mach_sh2a_nofpu_or_sh4_nommu_nofpu 0x2a1 + #define bfd_mach_sh2a_nofpu_or_sh3_nommu 0x2a2 + #define bfd_mach_sh2a_or_sh4 0x2a3 + #define bfd_mach_sh2a_or_sh3e 0x2a4 + #define bfd_mach_sh2e 0x2e + #define bfd_mach_sh3 0x30 + #define bfd_mach_sh3_nommu 0x31 + #define bfd_mach_sh3_dsp 0x3d + #define bfd_mach_sh3e 0x3e + #define bfd_mach_sh4 0x40 + #define bfd_mach_sh4_nofpu 0x41 + #define bfd_mach_sh4_nommu_nofpu 0x42 + #define bfd_mach_sh4a 0x4a + #define bfd_mach_sh4a_nofpu 0x4b + #define bfd_mach_sh4al_dsp 0x4d + #define bfd_mach_sh5 0x50 + bfd_arch_alpha, /* Dec Alpha */ + #define bfd_mach_alpha_ev4 0x10 + #define bfd_mach_alpha_ev5 0x20 + #define bfd_mach_alpha_ev6 0x30 + bfd_arch_arm, /* Advanced Risc Machines ARM. */ + #define bfd_mach_arm_unknown 0 + #define bfd_mach_arm_2 1 + #define bfd_mach_arm_2a 2 + #define bfd_mach_arm_3 3 + #define bfd_mach_arm_3M 4 + #define bfd_mach_arm_4 5 + #define bfd_mach_arm_4T 6 + #define bfd_mach_arm_5 7 + #define bfd_mach_arm_5T 8 + #define bfd_mach_arm_5TE 9 + #define bfd_mach_arm_XScale 10 + #define bfd_mach_arm_ep9312 11 + #define bfd_mach_arm_iWMMXt 12 + #define bfd_mach_arm_iWMMXt2 13 + bfd_arch_ns32k, /* National Semiconductors ns32000 */ + bfd_arch_w65, /* WDC 65816 */ + bfd_arch_tic30, /* Texas Instruments TMS320C30 */ + bfd_arch_tic4x, /* Texas Instruments TMS320C3X/4X */ + #define bfd_mach_tic3x 30 + #define bfd_mach_tic4x 40 + bfd_arch_tic54x, /* Texas Instruments TMS320C54X */ + bfd_arch_tic80, /* TI TMS320c80 (MVP) */ + bfd_arch_v850, /* NEC V850 */ + #define bfd_mach_v850 1 + #define bfd_mach_v850e 'E' + #define bfd_mach_v850e1 '1' + bfd_arch_arc, /* ARC Cores */ + #define bfd_mach_arc_5 5 + #define bfd_mach_arc_6 6 + #define bfd_mach_arc_7 7 + #define bfd_mach_arc_8 8 + bfd_arch_m32c, /* Renesas M16C/M32C. */ + #define bfd_mach_m16c 0x75 + #define bfd_mach_m32c 0x78 + bfd_arch_m32r, /* Renesas M32R (formerly Mitsubishi M32R/D) */ + #define bfd_mach_m32r 1 /* For backwards compatibility. */ + #define bfd_mach_m32rx 'x' + #define bfd_mach_m32r2 '2' + bfd_arch_mn10200, /* Matsushita MN10200 */ + bfd_arch_mn10300, /* Matsushita MN10300 */ + #define bfd_mach_mn10300 300 + #define bfd_mach_am33 330 + #define bfd_mach_am33_2 332 + bfd_arch_fr30, + #define bfd_mach_fr30 0x46523330 + bfd_arch_frv, + #define bfd_mach_frv 1 + #define bfd_mach_frvsimple 2 + #define bfd_mach_fr300 300 + #define bfd_mach_fr400 400 + #define bfd_mach_fr450 450 + #define bfd_mach_frvtomcat 499 /* fr500 prototype */ + #define bfd_mach_fr500 500 + #define bfd_mach_fr550 550 + bfd_arch_moxie, /* The moxie processor */ + #define bfd_mach_moxie 1 + bfd_arch_mcore, + bfd_arch_mep, + #define bfd_mach_mep 1 + #define bfd_mach_mep_h1 0x6831 + #define bfd_mach_mep_c5 0x6335 + bfd_arch_ia64, /* HP/Intel ia64 */ + #define bfd_mach_ia64_elf64 64 + #define bfd_mach_ia64_elf32 32 + bfd_arch_ip2k, /* Ubicom IP2K microcontrollers. */ + #define bfd_mach_ip2022 1 + #define bfd_mach_ip2022ext 2 + bfd_arch_iq2000, /* Vitesse IQ2000. */ + #define bfd_mach_iq2000 1 + #define bfd_mach_iq10 2 + bfd_arch_mt, + #define bfd_mach_ms1 1 + #define bfd_mach_mrisc2 2 + #define bfd_mach_ms2 3 + bfd_arch_pj, + bfd_arch_avr, /* Atmel AVR microcontrollers. */ + #define bfd_mach_avr1 1 + #define bfd_mach_avr2 2 + #define bfd_mach_avr25 25 + #define bfd_mach_avr3 3 + #define bfd_mach_avr31 31 + #define bfd_mach_avr35 35 + #define bfd_mach_avr4 4 + #define bfd_mach_avr5 5 + #define bfd_mach_avr51 51 + #define bfd_mach_avr6 6 + bfd_arch_bfin, /* ADI Blackfin */ + #define bfd_mach_bfin 1 + bfd_arch_cr16, /* National Semiconductor CompactRISC (ie CR16). */ + #define bfd_mach_cr16 1 + bfd_arch_cr16c, /* National Semiconductor CompactRISC. */ + #define bfd_mach_cr16c 1 + bfd_arch_crx, /* National Semiconductor CRX. */ + #define bfd_mach_crx 1 + bfd_arch_cris, /* Axis CRIS */ + #define bfd_mach_cris_v0_v10 255 + #define bfd_mach_cris_v32 32 + #define bfd_mach_cris_v10_v32 1032 + bfd_arch_s390, /* IBM s390 */ + #define bfd_mach_s390_31 31 + #define bfd_mach_s390_64 64 + bfd_arch_score, /* Sunplus score */ + #define bfd_mach_score3 3 + #define bfd_mach_score7 7 + bfd_arch_openrisc, /* OpenRISC */ + bfd_arch_mmix, /* Donald Knuth's educational processor. */ + bfd_arch_xstormy16, + #define bfd_mach_xstormy16 1 + bfd_arch_msp430, /* Texas Instruments MSP430 architecture. */ + #define bfd_mach_msp11 11 + #define bfd_mach_msp110 110 + #define bfd_mach_msp12 12 + #define bfd_mach_msp13 13 + #define bfd_mach_msp14 14 + #define bfd_mach_msp15 15 + #define bfd_mach_msp16 16 + #define bfd_mach_msp21 21 + #define bfd_mach_msp31 31 + #define bfd_mach_msp32 32 + #define bfd_mach_msp33 33 + #define bfd_mach_msp41 41 + #define bfd_mach_msp42 42 + #define bfd_mach_msp43 43 + #define bfd_mach_msp44 44 + bfd_arch_xc16x, /* Infineon's XC16X Series. */ + #define bfd_mach_xc16x 1 + #define bfd_mach_xc16xl 2 + #define bfd_mach_xc16xs 3 + bfd_arch_xtensa, /* Tensilica's Xtensa cores. */ + #define bfd_mach_xtensa 1 + bfd_arch_maxq, /* Dallas MAXQ 10/20 */ + #define bfd_mach_maxq10 10 + #define bfd_mach_maxq20 20 + bfd_arch_z80, + #define bfd_mach_z80strict 1 /* No undocumented opcodes. */ + #define bfd_mach_z80 3 /* With ixl, ixh, iyl, and iyh. */ + #define bfd_mach_z80full 7 /* All undocumented instructions. */ + #define bfd_mach_r800 11 /* R800: successor with multiplication. */ + bfd_arch_lm32, /* Lattice Mico32 */ + #define bfd_mach_lm32 1 + bfd_arch_microblaze,/* Xilinx MicroBlaze. */ + bfd_arch_last + }; + +2.13.2 bfd_arch_info +-------------------- + +*Description* +This structure contains information on architectures for use within BFD. + + typedef struct bfd_arch_info + { + int bits_per_word; + int bits_per_address; + int bits_per_byte; + enum bfd_architecture arch; + unsigned long mach; + const char *arch_name; + const char *printable_name; + unsigned int section_align_power; + /* TRUE if this is the default machine for the architecture. + The default arch should be the first entry for an arch so that + all the entries for that arch can be accessed via `next'. */ + bfd_boolean the_default; + const struct bfd_arch_info * (*compatible) + (const struct bfd_arch_info *a, const struct bfd_arch_info *b); + + bfd_boolean (*scan) (const struct bfd_arch_info *, const char *); + + const struct bfd_arch_info *next; + } + bfd_arch_info_type; + +2.13.2.1 `bfd_printable_name' +............................. + +*Synopsis* + const char *bfd_printable_name (bfd *abfd); + *Description* +Return a printable string representing the architecture and machine +from the pointer to the architecture info structure. + +2.13.2.2 `bfd_scan_arch' +........................ + +*Synopsis* + const bfd_arch_info_type *bfd_scan_arch (const char *string); + *Description* +Figure out if BFD supports any cpu which could be described with the +name STRING. Return a pointer to an `arch_info' structure if a machine +is found, otherwise NULL. + +2.13.2.3 `bfd_arch_list' +........................ + +*Synopsis* + const char **bfd_arch_list (void); + *Description* +Return a freshly malloced NULL-terminated vector of the names of all +the valid BFD architectures. Do not modify the names. + +2.13.2.4 `bfd_arch_get_compatible' +.................................. + +*Synopsis* + const bfd_arch_info_type *bfd_arch_get_compatible + (const bfd *abfd, const bfd *bbfd, bfd_boolean accept_unknowns); + *Description* +Determine whether two BFDs' architectures and machine types are +compatible. Calculates the lowest common denominator between the two +architectures and machine types implied by the BFDs and returns a +pointer to an `arch_info' structure describing the compatible machine. + +2.13.2.5 `bfd_default_arch_struct' +.................................. + +*Description* +The `bfd_default_arch_struct' is an item of `bfd_arch_info_type' which +has been initialized to a fairly generic state. A BFD starts life by +pointing to this structure, until the correct back end has determined +the real architecture of the file. + extern const bfd_arch_info_type bfd_default_arch_struct; + +2.13.2.6 `bfd_set_arch_info' +............................ + +*Synopsis* + void bfd_set_arch_info (bfd *abfd, const bfd_arch_info_type *arg); + *Description* +Set the architecture info of ABFD to ARG. + +2.13.2.7 `bfd_default_set_arch_mach' +.................................... + +*Synopsis* + bfd_boolean bfd_default_set_arch_mach + (bfd *abfd, enum bfd_architecture arch, unsigned long mach); + *Description* +Set the architecture and machine type in BFD ABFD to ARCH and MACH. +Find the correct pointer to a structure and insert it into the +`arch_info' pointer. + +2.13.2.8 `bfd_get_arch' +....................... + +*Synopsis* + enum bfd_architecture bfd_get_arch (bfd *abfd); + *Description* +Return the enumerated type which describes the BFD ABFD's architecture. + +2.13.2.9 `bfd_get_mach' +....................... + +*Synopsis* + unsigned long bfd_get_mach (bfd *abfd); + *Description* +Return the long type which describes the BFD ABFD's machine. + +2.13.2.10 `bfd_arch_bits_per_byte' +.................................. + +*Synopsis* + unsigned int bfd_arch_bits_per_byte (bfd *abfd); + *Description* +Return the number of bits in one of the BFD ABFD's architecture's bytes. + +2.13.2.11 `bfd_arch_bits_per_address' +..................................... + +*Synopsis* + unsigned int bfd_arch_bits_per_address (bfd *abfd); + *Description* +Return the number of bits in one of the BFD ABFD's architecture's +addresses. + +2.13.2.12 `bfd_default_compatible' +.................................. + +*Synopsis* + const bfd_arch_info_type *bfd_default_compatible + (const bfd_arch_info_type *a, const bfd_arch_info_type *b); + *Description* +The default function for testing for compatibility. + +2.13.2.13 `bfd_default_scan' +............................ + +*Synopsis* + bfd_boolean bfd_default_scan + (const struct bfd_arch_info *info, const char *string); + *Description* +The default function for working out whether this is an architecture +hit and a machine hit. + +2.13.2.14 `bfd_get_arch_info' +............................. + +*Synopsis* + const bfd_arch_info_type *bfd_get_arch_info (bfd *abfd); + *Description* +Return the architecture info struct in ABFD. + +2.13.2.15 `bfd_lookup_arch' +........................... + +*Synopsis* + const bfd_arch_info_type *bfd_lookup_arch + (enum bfd_architecture arch, unsigned long machine); + *Description* +Look for the architecture info structure which matches the arguments +ARCH and MACHINE. A machine of 0 matches the machine/architecture +structure which marks itself as the default. + +2.13.2.16 `bfd_printable_arch_mach' +................................... + +*Synopsis* + const char *bfd_printable_arch_mach + (enum bfd_architecture arch, unsigned long machine); + *Description* +Return a printable string representing the architecture and machine +type. + + This routine is depreciated. + +2.13.2.17 `bfd_octets_per_byte' +............................... + +*Synopsis* + unsigned int bfd_octets_per_byte (bfd *abfd); + *Description* +Return the number of octets (8-bit quantities) per target byte (minimum +addressable unit). In most cases, this will be one, but some DSP +targets have 16, 32, or even 48 bits per byte. + +2.13.2.18 `bfd_arch_mach_octets_per_byte' +......................................... + +*Synopsis* + unsigned int bfd_arch_mach_octets_per_byte + (enum bfd_architecture arch, unsigned long machine); + *Description* +See bfd_octets_per_byte. + + This routine is provided for those cases where a bfd * is not +available + + +File: bfd.info, Node: Opening and Closing, Next: Internal, Prev: Architectures, Up: BFD front end + +2.14 Opening and closing BFDs +============================= + +2.14.1 Functions for opening and closing +---------------------------------------- + +2.14.1.1 `bfd_fopen' +.................... + +*Synopsis* + bfd *bfd_fopen (const char *filename, const char *target, + const char *mode, int fd); + *Description* +Open the file FILENAME with the target TARGET. Return a pointer to the +created BFD. If FD is not -1, then `fdopen' is used to open the file; +otherwise, `fopen' is used. MODE is passed directly to `fopen' or +`fdopen'. + + Calls `bfd_find_target', so TARGET is interpreted as by that +function. + + The new BFD is marked as cacheable iff FD is -1. + + If `NULL' is returned then an error has occured. Possible errors +are `bfd_error_no_memory', `bfd_error_invalid_target' or `system_call' +error. + +2.14.1.2 `bfd_openr' +.................... + +*Synopsis* + bfd *bfd_openr (const char *filename, const char *target); + *Description* +Open the file FILENAME (using `fopen') with the target TARGET. Return +a pointer to the created BFD. + + Calls `bfd_find_target', so TARGET is interpreted as by that +function. + + If `NULL' is returned then an error has occured. Possible errors +are `bfd_error_no_memory', `bfd_error_invalid_target' or `system_call' +error. + +2.14.1.3 `bfd_fdopenr' +...................... + +*Synopsis* + bfd *bfd_fdopenr (const char *filename, const char *target, int fd); + *Description* +`bfd_fdopenr' is to `bfd_fopenr' much like `fdopen' is to `fopen'. It +opens a BFD on a file already described by the FD supplied. + + When the file is later `bfd_close'd, the file descriptor will be +closed. If the caller desires that this file descriptor be cached by +BFD (opened as needed, closed as needed to free descriptors for other +opens), with the supplied FD used as an initial file descriptor (but +subject to closure at any time), call bfd_set_cacheable(bfd, 1) on the +returned BFD. The default is to assume no caching; the file descriptor +will remain open until `bfd_close', and will not be affected by BFD +operations on other files. + + Possible errors are `bfd_error_no_memory', +`bfd_error_invalid_target' and `bfd_error_system_call'. + +2.14.1.4 `bfd_openstreamr' +.......................... + +*Synopsis* + bfd *bfd_openstreamr (const char *, const char *, void *); + *Description* +Open a BFD for read access on an existing stdio stream. When the BFD +is passed to `bfd_close', the stream will be closed. + +2.14.1.5 `bfd_openr_iovec' +.......................... + +*Synopsis* + bfd *bfd_openr_iovec (const char *filename, const char *target, + void *(*open) (struct bfd *nbfd, + void *open_closure), + void *open_closure, + file_ptr (*pread) (struct bfd *nbfd, + void *stream, + void *buf, + file_ptr nbytes, + file_ptr offset), + int (*close) (struct bfd *nbfd, + void *stream), + int (*stat) (struct bfd *abfd, + void *stream, + struct stat *sb)); + *Description* +Create and return a BFD backed by a read-only STREAM. The STREAM is +created using OPEN, accessed using PREAD and destroyed using CLOSE. + + Calls `bfd_find_target', so TARGET is interpreted as by that +function. + + Calls OPEN (which can call `bfd_zalloc' and `bfd_get_filename') to +obtain the read-only stream backing the BFD. OPEN either succeeds +returning the non-`NULL' STREAM, or fails returning `NULL' (setting +`bfd_error'). + + Calls PREAD to request NBYTES of data from STREAM starting at OFFSET +(e.g., via a call to `bfd_read'). PREAD either succeeds returning the +number of bytes read (which can be less than NBYTES when end-of-file), +or fails returning -1 (setting `bfd_error'). + + Calls CLOSE when the BFD is later closed using `bfd_close'. CLOSE +either succeeds returning 0, or fails returning -1 (setting +`bfd_error'). + + Calls STAT to fill in a stat structure for bfd_stat, bfd_get_size, +and bfd_get_mtime calls. STAT returns 0 on success, or returns -1 on +failure (setting `bfd_error'). + + If `bfd_openr_iovec' returns `NULL' then an error has occurred. +Possible errors are `bfd_error_no_memory', `bfd_error_invalid_target' +and `bfd_error_system_call'. + +2.14.1.6 `bfd_openw' +.................... + +*Synopsis* + bfd *bfd_openw (const char *filename, const char *target); + *Description* +Create a BFD, associated with file FILENAME, using the file format +TARGET, and return a pointer to it. + + Possible errors are `bfd_error_system_call', `bfd_error_no_memory', +`bfd_error_invalid_target'. + +2.14.1.7 `bfd_close' +.................... + +*Synopsis* + bfd_boolean bfd_close (bfd *abfd); + *Description* +Close a BFD. If the BFD was open for writing, then pending operations +are completed and the file written out and closed. If the created file +is executable, then `chmod' is called to mark it as such. + + All memory attached to the BFD is released. + + The file descriptor associated with the BFD is closed (even if it +was passed in to BFD by `bfd_fdopenr'). + + *Returns* +`TRUE' is returned if all is ok, otherwise `FALSE'. + +2.14.1.8 `bfd_close_all_done' +............................. + +*Synopsis* + bfd_boolean bfd_close_all_done (bfd *); + *Description* +Close a BFD. Differs from `bfd_close' since it does not complete any +pending operations. This routine would be used if the application had +just used BFD for swapping and didn't want to use any of the writing +code. + + If the created file is executable, then `chmod' is called to mark it +as such. + + All memory attached to the BFD is released. + + *Returns* +`TRUE' is returned if all is ok, otherwise `FALSE'. + +2.14.1.9 `bfd_create' +..................... + +*Synopsis* + bfd *bfd_create (const char *filename, bfd *templ); + *Description* +Create a new BFD in the manner of `bfd_openw', but without opening a +file. The new BFD takes the target from the target used by TEMPLATE. +The format is always set to `bfd_object'. + +2.14.1.10 `bfd_make_writable' +............................. + +*Synopsis* + bfd_boolean bfd_make_writable (bfd *abfd); + *Description* +Takes a BFD as created by `bfd_create' and converts it into one like as +returned by `bfd_openw'. It does this by converting the BFD to +BFD_IN_MEMORY. It's assumed that you will call `bfd_make_readable' on +this bfd later. + + *Returns* +`TRUE' is returned if all is ok, otherwise `FALSE'. + +2.14.1.11 `bfd_make_readable' +............................. + +*Synopsis* + bfd_boolean bfd_make_readable (bfd *abfd); + *Description* +Takes a BFD as created by `bfd_create' and `bfd_make_writable' and +converts it into one like as returned by `bfd_openr'. It does this by +writing the contents out to the memory buffer, then reversing the +direction. + + *Returns* +`TRUE' is returned if all is ok, otherwise `FALSE'. + +2.14.1.12 `bfd_alloc' +..................... + +*Synopsis* + void *bfd_alloc (bfd *abfd, bfd_size_type wanted); + *Description* +Allocate a block of WANTED bytes of memory attached to `abfd' and +return a pointer to it. + +2.14.1.13 `bfd_alloc2' +...................... + +*Synopsis* + void *bfd_alloc2 (bfd *abfd, bfd_size_type nmemb, bfd_size_type size); + *Description* +Allocate a block of NMEMB elements of SIZE bytes each of memory +attached to `abfd' and return a pointer to it. + +2.14.1.14 `bfd_zalloc' +...................... + +*Synopsis* + void *bfd_zalloc (bfd *abfd, bfd_size_type wanted); + *Description* +Allocate a block of WANTED bytes of zeroed memory attached to `abfd' +and return a pointer to it. + +2.14.1.15 `bfd_zalloc2' +....................... + +*Synopsis* + void *bfd_zalloc2 (bfd *abfd, bfd_size_type nmemb, bfd_size_type size); + *Description* +Allocate a block of NMEMB elements of SIZE bytes each of zeroed memory +attached to `abfd' and return a pointer to it. + +2.14.1.16 `bfd_calc_gnu_debuglink_crc32' +........................................ + +*Synopsis* + unsigned long bfd_calc_gnu_debuglink_crc32 + (unsigned long crc, const unsigned char *buf, bfd_size_type len); + *Description* +Computes a CRC value as used in the .gnu_debuglink section. Advances +the previously computed CRC value by computing and adding in the crc32 +for LEN bytes of BUF. + + *Returns* +Return the updated CRC32 value. + +2.14.1.17 `get_debug_link_info' +............................... + +*Synopsis* + char *get_debug_link_info (bfd *abfd, unsigned long *crc32_out); + *Description* +fetch the filename and CRC32 value for any separate debuginfo +associated with ABFD. Return NULL if no such info found, otherwise +return filename and update CRC32_OUT. + +2.14.1.18 `separate_debug_file_exists' +...................................... + +*Synopsis* + bfd_boolean separate_debug_file_exists + (char *name, unsigned long crc32); + *Description* +Checks to see if NAME is a file and if its contents match CRC32. + +2.14.1.19 `find_separate_debug_file' +.................................... + +*Synopsis* + char *find_separate_debug_file (bfd *abfd); + *Description* +Searches ABFD for a reference to separate debugging information, scans +various locations in the filesystem, including the file tree rooted at +DEBUG_FILE_DIRECTORY, and returns a filename of such debugging +information if the file is found and has matching CRC32. Returns NULL +if no reference to debugging file exists, or file cannot be found. + +2.14.1.20 `bfd_follow_gnu_debuglink' +.................................... + +*Synopsis* + char *bfd_follow_gnu_debuglink (bfd *abfd, const char *dir); + *Description* +Takes a BFD and searches it for a .gnu_debuglink section. If this +section is found, it examines the section for the name and checksum of +a '.debug' file containing auxiliary debugging information. It then +searches the filesystem for this .debug file in some standard +locations, including the directory tree rooted at DIR, and if found +returns the full filename. + + If DIR is NULL, it will search a default path configured into libbfd +at build time. [XXX this feature is not currently implemented]. + + *Returns* +`NULL' on any errors or failure to locate the .debug file, otherwise a +pointer to a heap-allocated string containing the filename. The caller +is responsible for freeing this string. + +2.14.1.21 `bfd_create_gnu_debuglink_section' +............................................ + +*Synopsis* + struct bfd_section *bfd_create_gnu_debuglink_section + (bfd *abfd, const char *filename); + *Description* +Takes a BFD and adds a .gnu_debuglink section to it. The section is +sized to be big enough to contain a link to the specified FILENAME. + + *Returns* +A pointer to the new section is returned if all is ok. Otherwise +`NULL' is returned and bfd_error is set. + +2.14.1.22 `bfd_fill_in_gnu_debuglink_section' +............................................. + +*Synopsis* + bfd_boolean bfd_fill_in_gnu_debuglink_section + (bfd *abfd, struct bfd_section *sect, const char *filename); + *Description* +Takes a BFD and containing a .gnu_debuglink section SECT and fills in +the contents of the section to contain a link to the specified +FILENAME. The filename should be relative to the current directory. + + *Returns* +`TRUE' is returned if all is ok. Otherwise `FALSE' is returned and +bfd_error is set. + + +File: bfd.info, Node: Internal, Next: File Caching, Prev: Opening and Closing, Up: BFD front end + +2.15 Implementation details +=========================== + +2.15.1 Internal functions +------------------------- + +*Description* +These routines are used within BFD. They are not intended for export, +but are documented here for completeness. + +2.15.1.1 `bfd_write_bigendian_4byte_int' +........................................ + +*Synopsis* + bfd_boolean bfd_write_bigendian_4byte_int (bfd *, unsigned int); + *Description* +Write a 4 byte integer I to the output BFD ABFD, in big endian order +regardless of what else is going on. This is useful in archives. + +2.15.1.2 `bfd_put_size' +....................... + +2.15.1.3 `bfd_get_size' +....................... + +*Description* +These macros as used for reading and writing raw data in sections; each +access (except for bytes) is vectored through the target format of the +BFD and mangled accordingly. The mangling performs any necessary endian +translations and removes alignment restrictions. Note that types +accepted and returned by these macros are identical so they can be +swapped around in macros--for example, `libaout.h' defines `GET_WORD' +to either `bfd_get_32' or `bfd_get_64'. + + In the put routines, VAL must be a `bfd_vma'. If we are on a system +without prototypes, the caller is responsible for making sure that is +true, with a cast if necessary. We don't cast them in the macro +definitions because that would prevent `lint' or `gcc -Wall' from +detecting sins such as passing a pointer. To detect calling these with +less than a `bfd_vma', use `gcc -Wconversion' on a host with 64 bit +`bfd_vma''s. + + /* Byte swapping macros for user section data. */ + + #define bfd_put_8(abfd, val, ptr) \ + ((void) (*((unsigned char *) (ptr)) = (val) & 0xff)) + #define bfd_put_signed_8 \ + bfd_put_8 + #define bfd_get_8(abfd, ptr) \ + (*(unsigned char *) (ptr) & 0xff) + #define bfd_get_signed_8(abfd, ptr) \ + (((*(unsigned char *) (ptr) & 0xff) ^ 0x80) - 0x80) + + #define bfd_put_16(abfd, val, ptr) \ + BFD_SEND (abfd, bfd_putx16, ((val),(ptr))) + #define bfd_put_signed_16 \ + bfd_put_16 + #define bfd_get_16(abfd, ptr) \ + BFD_SEND (abfd, bfd_getx16, (ptr)) + #define bfd_get_signed_16(abfd, ptr) \ + BFD_SEND (abfd, bfd_getx_signed_16, (ptr)) + + #define bfd_put_32(abfd, val, ptr) \ + BFD_SEND (abfd, bfd_putx32, ((val),(ptr))) + #define bfd_put_signed_32 \ + bfd_put_32 + #define bfd_get_32(abfd, ptr) \ + BFD_SEND (abfd, bfd_getx32, (ptr)) + #define bfd_get_signed_32(abfd, ptr) \ + BFD_SEND (abfd, bfd_getx_signed_32, (ptr)) + + #define bfd_put_64(abfd, val, ptr) \ + BFD_SEND (abfd, bfd_putx64, ((val), (ptr))) + #define bfd_put_signed_64 \ + bfd_put_64 + #define bfd_get_64(abfd, ptr) \ + BFD_SEND (abfd, bfd_getx64, (ptr)) + #define bfd_get_signed_64(abfd, ptr) \ + BFD_SEND (abfd, bfd_getx_signed_64, (ptr)) + + #define bfd_get(bits, abfd, ptr) \ + ((bits) == 8 ? (bfd_vma) bfd_get_8 (abfd, ptr) \ + : (bits) == 16 ? bfd_get_16 (abfd, ptr) \ + : (bits) == 32 ? bfd_get_32 (abfd, ptr) \ + : (bits) == 64 ? bfd_get_64 (abfd, ptr) \ + : (abort (), (bfd_vma) - 1)) + + #define bfd_put(bits, abfd, val, ptr) \ + ((bits) == 8 ? bfd_put_8 (abfd, val, ptr) \ + : (bits) == 16 ? bfd_put_16 (abfd, val, ptr) \ + : (bits) == 32 ? bfd_put_32 (abfd, val, ptr) \ + : (bits) == 64 ? bfd_put_64 (abfd, val, ptr) \ + : (abort (), (void) 0)) + +2.15.1.4 `bfd_h_put_size' +......................... + +*Description* +These macros have the same function as their `bfd_get_x' brethren, +except that they are used for removing information for the header +records of object files. Believe it or not, some object files keep +their header records in big endian order and their data in little +endian order. + + /* Byte swapping macros for file header data. */ + + #define bfd_h_put_8(abfd, val, ptr) \ + bfd_put_8 (abfd, val, ptr) + #define bfd_h_put_signed_8(abfd, val, ptr) \ + bfd_put_8 (abfd, val, ptr) + #define bfd_h_get_8(abfd, ptr) \ + bfd_get_8 (abfd, ptr) + #define bfd_h_get_signed_8(abfd, ptr) \ + bfd_get_signed_8 (abfd, ptr) + + #define bfd_h_put_16(abfd, val, ptr) \ + BFD_SEND (abfd, bfd_h_putx16, (val, ptr)) + #define bfd_h_put_signed_16 \ + bfd_h_put_16 + #define bfd_h_get_16(abfd, ptr) \ + BFD_SEND (abfd, bfd_h_getx16, (ptr)) + #define bfd_h_get_signed_16(abfd, ptr) \ + BFD_SEND (abfd, bfd_h_getx_signed_16, (ptr)) + + #define bfd_h_put_32(abfd, val, ptr) \ + BFD_SEND (abfd, bfd_h_putx32, (val, ptr)) + #define bfd_h_put_signed_32 \ + bfd_h_put_32 + #define bfd_h_get_32(abfd, ptr) \ + BFD_SEND (abfd, bfd_h_getx32, (ptr)) + #define bfd_h_get_signed_32(abfd, ptr) \ + BFD_SEND (abfd, bfd_h_getx_signed_32, (ptr)) + + #define bfd_h_put_64(abfd, val, ptr) \ + BFD_SEND (abfd, bfd_h_putx64, (val, ptr)) + #define bfd_h_put_signed_64 \ + bfd_h_put_64 + #define bfd_h_get_64(abfd, ptr) \ + BFD_SEND (abfd, bfd_h_getx64, (ptr)) + #define bfd_h_get_signed_64(abfd, ptr) \ + BFD_SEND (abfd, bfd_h_getx_signed_64, (ptr)) + + /* Aliases for the above, which should eventually go away. */ + + #define H_PUT_64 bfd_h_put_64 + #define H_PUT_32 bfd_h_put_32 + #define H_PUT_16 bfd_h_put_16 + #define H_PUT_8 bfd_h_put_8 + #define H_PUT_S64 bfd_h_put_signed_64 + #define H_PUT_S32 bfd_h_put_signed_32 + #define H_PUT_S16 bfd_h_put_signed_16 + #define H_PUT_S8 bfd_h_put_signed_8 + #define H_GET_64 bfd_h_get_64 + #define H_GET_32 bfd_h_get_32 + #define H_GET_16 bfd_h_get_16 + #define H_GET_8 bfd_h_get_8 + #define H_GET_S64 bfd_h_get_signed_64 + #define H_GET_S32 bfd_h_get_signed_32 + #define H_GET_S16 bfd_h_get_signed_16 + #define H_GET_S8 bfd_h_get_signed_8 + +2.15.1.5 `bfd_log2' +................... + +*Synopsis* + unsigned int bfd_log2 (bfd_vma x); + *Description* +Return the log base 2 of the value supplied, rounded up. E.g., an X of +1025 returns 11. A X of 0 returns 0. + + +File: bfd.info, Node: File Caching, Next: Linker Functions, Prev: Internal, Up: BFD front end + +2.16 File caching +================= + +The file caching mechanism is embedded within BFD and allows the +application to open as many BFDs as it wants without regard to the +underlying operating system's file descriptor limit (often as low as 20 +open files). The module in `cache.c' maintains a least recently used +list of `BFD_CACHE_MAX_OPEN' files, and exports the name +`bfd_cache_lookup', which runs around and makes sure that the required +BFD is open. If not, then it chooses a file to close, closes it and +opens the one wanted, returning its file handle. + +2.16.1 Caching functions +------------------------ + +2.16.1.1 `bfd_cache_init' +......................... + +*Synopsis* + bfd_boolean bfd_cache_init (bfd *abfd); + *Description* +Add a newly opened BFD to the cache. + +2.16.1.2 `bfd_cache_close' +.......................... + +*Synopsis* + bfd_boolean bfd_cache_close (bfd *abfd); + *Description* +Remove the BFD ABFD from the cache. If the attached file is open, then +close it too. + + *Returns* +`FALSE' is returned if closing the file fails, `TRUE' is returned if +all is well. + +2.16.1.3 `bfd_cache_close_all' +.............................. + +*Synopsis* + bfd_boolean bfd_cache_close_all (void); + *Description* +Remove all BFDs from the cache. If the attached file is open, then +close it too. + + *Returns* +`FALSE' is returned if closing one of the file fails, `TRUE' is +returned if all is well. + +2.16.1.4 `bfd_open_file' +........................ + +*Synopsis* + FILE* bfd_open_file (bfd *abfd); + *Description* +Call the OS to open a file for ABFD. Return the `FILE *' (possibly +`NULL') that results from this operation. Set up the BFD so that +future accesses know the file is open. If the `FILE *' returned is +`NULL', then it won't have been put in the cache, so it won't have to +be removed from it. + + +File: bfd.info, Node: Linker Functions, Next: Hash Tables, Prev: File Caching, Up: BFD front end + +2.17 Linker Functions +===================== + +The linker uses three special entry points in the BFD target vector. +It is not necessary to write special routines for these entry points +when creating a new BFD back end, since generic versions are provided. +However, writing them can speed up linking and make it use +significantly less runtime memory. + + The first routine creates a hash table used by the other routines. +The second routine adds the symbols from an object file to the hash +table. The third routine takes all the object files and links them +together to create the output file. These routines are designed so +that the linker proper does not need to know anything about the symbols +in the object files that it is linking. The linker merely arranges the +sections as directed by the linker script and lets BFD handle the +details of symbols and relocs. + + The second routine and third routines are passed a pointer to a +`struct bfd_link_info' structure (defined in `bfdlink.h') which holds +information relevant to the link, including the linker hash table +(which was created by the first routine) and a set of callback +functions to the linker proper. + + The generic linker routines are in `linker.c', and use the header +file `genlink.h'. As of this writing, the only back ends which have +implemented versions of these routines are a.out (in `aoutx.h') and +ECOFF (in `ecoff.c'). The a.out routines are used as examples +throughout this section. + +* Menu: + +* Creating a Linker Hash Table:: +* Adding Symbols to the Hash Table:: +* Performing the Final Link:: + + +File: bfd.info, Node: Creating a Linker Hash Table, Next: Adding Symbols to the Hash Table, Prev: Linker Functions, Up: Linker Functions + +2.17.1 Creating a linker hash table +----------------------------------- + +The linker routines must create a hash table, which must be derived +from `struct bfd_link_hash_table' described in `bfdlink.c'. *Note Hash +Tables::, for information on how to create a derived hash table. This +entry point is called using the target vector of the linker output file. + + The `_bfd_link_hash_table_create' entry point must allocate and +initialize an instance of the desired hash table. If the back end does +not require any additional information to be stored with the entries in +the hash table, the entry point may simply create a `struct +bfd_link_hash_table'. Most likely, however, some additional +information will be needed. + + For example, with each entry in the hash table the a.out linker +keeps the index the symbol has in the final output file (this index +number is used so that when doing a relocatable link the symbol index +used in the output file can be quickly filled in when copying over a +reloc). The a.out linker code defines the required structures and +functions for a hash table derived from `struct bfd_link_hash_table'. +The a.out linker hash table is created by the function +`NAME(aout,link_hash_table_create)'; it simply allocates space for the +hash table, initializes it, and returns a pointer to it. + + When writing the linker routines for a new back end, you will +generally not know exactly which fields will be required until you have +finished. You should simply create a new hash table which defines no +additional fields, and then simply add fields as they become necessary. + + +File: bfd.info, Node: Adding Symbols to the Hash Table, Next: Performing the Final Link, Prev: Creating a Linker Hash Table, Up: Linker Functions + +2.17.2 Adding symbols to the hash table +--------------------------------------- + +The linker proper will call the `_bfd_link_add_symbols' entry point for +each object file or archive which is to be linked (typically these are +the files named on the command line, but some may also come from the +linker script). The entry point is responsible for examining the file. +For an object file, BFD must add any relevant symbol information to +the hash table. For an archive, BFD must determine which elements of +the archive should be used and adding them to the link. + + The a.out version of this entry point is +`NAME(aout,link_add_symbols)'. + +* Menu: + +* Differing file formats:: +* Adding symbols from an object file:: +* Adding symbols from an archive:: + + +File: bfd.info, Node: Differing file formats, Next: Adding symbols from an object file, Prev: Adding Symbols to the Hash Table, Up: Adding Symbols to the Hash Table + +2.17.2.1 Differing file formats +............................... + +Normally all the files involved in a link will be of the same format, +but it is also possible to link together different format object files, +and the back end must support that. The `_bfd_link_add_symbols' entry +point is called via the target vector of the file to be added. This +has an important consequence: the function may not assume that the hash +table is the type created by the corresponding +`_bfd_link_hash_table_create' vector. All the `_bfd_link_add_symbols' +function can assume about the hash table is that it is derived from +`struct bfd_link_hash_table'. + + Sometimes the `_bfd_link_add_symbols' function must store some +information in the hash table entry to be used by the `_bfd_final_link' +function. In such a case the output bfd xvec must be checked to make +sure that the hash table was created by an object file of the same +format. + + The `_bfd_final_link' routine must be prepared to handle a hash +entry without any extra information added by the +`_bfd_link_add_symbols' function. A hash entry without extra +information will also occur when the linker script directs the linker +to create a symbol. Note that, regardless of how a hash table entry is +added, all the fields will be initialized to some sort of null value by +the hash table entry initialization function. + + See `ecoff_link_add_externals' for an example of how to check the +output bfd before saving information (in this case, the ECOFF external +symbol debugging information) in a hash table entry. + + +File: bfd.info, Node: Adding symbols from an object file, Next: Adding symbols from an archive, Prev: Differing file formats, Up: Adding Symbols to the Hash Table + +2.17.2.2 Adding symbols from an object file +........................................... + +When the `_bfd_link_add_symbols' routine is passed an object file, it +must add all externally visible symbols in that object file to the hash +table. The actual work of adding the symbol to the hash table is +normally handled by the function `_bfd_generic_link_add_one_symbol'. +The `_bfd_link_add_symbols' routine is responsible for reading all the +symbols from the object file and passing the correct information to +`_bfd_generic_link_add_one_symbol'. + + The `_bfd_link_add_symbols' routine should not use +`bfd_canonicalize_symtab' to read the symbols. The point of providing +this routine is to avoid the overhead of converting the symbols into +generic `asymbol' structures. + + `_bfd_generic_link_add_one_symbol' handles the details of combining +common symbols, warning about multiple definitions, and so forth. It +takes arguments which describe the symbol to add, notably symbol flags, +a section, and an offset. The symbol flags include such things as +`BSF_WEAK' or `BSF_INDIRECT'. The section is a section in the object +file, or something like `bfd_und_section_ptr' for an undefined symbol +or `bfd_com_section_ptr' for a common symbol. + + If the `_bfd_final_link' routine is also going to need to read the +symbol information, the `_bfd_link_add_symbols' routine should save it +somewhere attached to the object file BFD. However, the information +should only be saved if the `keep_memory' field of the `info' argument +is TRUE, so that the `-no-keep-memory' linker switch is effective. + + The a.out function which adds symbols from an object file is +`aout_link_add_object_symbols', and most of the interesting work is in +`aout_link_add_symbols'. The latter saves pointers to the hash tables +entries created by `_bfd_generic_link_add_one_symbol' indexed by symbol +number, so that the `_bfd_final_link' routine does not have to call the +hash table lookup routine to locate the entry. + + +File: bfd.info, Node: Adding symbols from an archive, Prev: Adding symbols from an object file, Up: Adding Symbols to the Hash Table + +2.17.2.3 Adding symbols from an archive +....................................... + +When the `_bfd_link_add_symbols' routine is passed an archive, it must +look through the symbols defined by the archive and decide which +elements of the archive should be included in the link. For each such +element it must call the `add_archive_element' linker callback, and it +must add the symbols from the object file to the linker hash table. + + In most cases the work of looking through the symbols in the archive +should be done by the `_bfd_generic_link_add_archive_symbols' function. +This function builds a hash table from the archive symbol table and +looks through the list of undefined symbols to see which elements +should be included. `_bfd_generic_link_add_archive_symbols' is passed +a function to call to make the final decision about adding an archive +element to the link and to do the actual work of adding the symbols to +the linker hash table. + + The function passed to `_bfd_generic_link_add_archive_symbols' must +read the symbols of the archive element and decide whether the archive +element should be included in the link. If the element is to be +included, the `add_archive_element' linker callback routine must be +called with the element as an argument, and the elements symbols must +be added to the linker hash table just as though the element had itself +been passed to the `_bfd_link_add_symbols' function. + + When the a.out `_bfd_link_add_symbols' function receives an archive, +it calls `_bfd_generic_link_add_archive_symbols' passing +`aout_link_check_archive_element' as the function argument. +`aout_link_check_archive_element' calls `aout_link_check_ar_symbols'. +If the latter decides to add the element (an element is only added if +it provides a real, non-common, definition for a previously undefined +or common symbol) it calls the `add_archive_element' callback and then +`aout_link_check_archive_element' calls `aout_link_add_symbols' to +actually add the symbols to the linker hash table. + + The ECOFF back end is unusual in that it does not normally call +`_bfd_generic_link_add_archive_symbols', because ECOFF archives already +contain a hash table of symbols. The ECOFF back end searches the +archive itself to avoid the overhead of creating a new hash table. + + +File: bfd.info, Node: Performing the Final Link, Prev: Adding Symbols to the Hash Table, Up: Linker Functions + +2.17.3 Performing the final link +-------------------------------- + +When all the input files have been processed, the linker calls the +`_bfd_final_link' entry point of the output BFD. This routine is +responsible for producing the final output file, which has several +aspects. It must relocate the contents of the input sections and copy +the data into the output sections. It must build an output symbol +table including any local symbols from the input files and the global +symbols from the hash table. When producing relocatable output, it must +modify the input relocs and write them into the output file. There may +also be object format dependent work to be done. + + The linker will also call the `write_object_contents' entry point +when the BFD is closed. The two entry points must work together in +order to produce the correct output file. + + The details of how this works are inevitably dependent upon the +specific object file format. The a.out `_bfd_final_link' routine is +`NAME(aout,final_link)'. + +* Menu: + +* Information provided by the linker:: +* Relocating the section contents:: +* Writing the symbol table:: + + +File: bfd.info, Node: Information provided by the linker, Next: Relocating the section contents, Prev: Performing the Final Link, Up: Performing the Final Link + +2.17.3.1 Information provided by the linker +........................................... + +Before the linker calls the `_bfd_final_link' entry point, it sets up +some data structures for the function to use. + + The `input_bfds' field of the `bfd_link_info' structure will point +to a list of all the input files included in the link. These files are +linked through the `link_next' field of the `bfd' structure. + + Each section in the output file will have a list of `link_order' +structures attached to the `map_head.link_order' field (the +`link_order' structure is defined in `bfdlink.h'). These structures +describe how to create the contents of the output section in terms of +the contents of various input sections, fill constants, and, +eventually, other types of information. They also describe relocs that +must be created by the BFD backend, but do not correspond to any input +file; this is used to support -Ur, which builds constructors while +generating a relocatable object file. + + +File: bfd.info, Node: Relocating the section contents, Next: Writing the symbol table, Prev: Information provided by the linker, Up: Performing the Final Link + +2.17.3.2 Relocating the section contents +........................................ + +The `_bfd_final_link' function should look through the `link_order' +structures attached to each section of the output file. Each +`link_order' structure should either be handled specially, or it should +be passed to the function `_bfd_default_link_order' which will do the +right thing (`_bfd_default_link_order' is defined in `linker.c'). + + For efficiency, a `link_order' of type `bfd_indirect_link_order' +whose associated section belongs to a BFD of the same format as the +output BFD must be handled specially. This type of `link_order' +describes part of an output section in terms of a section belonging to +one of the input files. The `_bfd_final_link' function should read the +contents of the section and any associated relocs, apply the relocs to +the section contents, and write out the modified section contents. If +performing a relocatable link, the relocs themselves must also be +modified and written out. + + The functions `_bfd_relocate_contents' and +`_bfd_final_link_relocate' provide some general support for performing +the actual relocations, notably overflow checking. Their arguments +include information about the symbol the relocation is against and a +`reloc_howto_type' argument which describes the relocation to perform. +These functions are defined in `reloc.c'. + + The a.out function which handles reading, relocating, and writing +section contents is `aout_link_input_section'. The actual relocation +is done in `aout_link_input_section_std' and +`aout_link_input_section_ext'. + + +File: bfd.info, Node: Writing the symbol table, Prev: Relocating the section contents, Up: Performing the Final Link + +2.17.3.3 Writing the symbol table +................................. + +The `_bfd_final_link' function must gather all the symbols in the input +files and write them out. It must also write out all the symbols in +the global hash table. This must be controlled by the `strip' and +`discard' fields of the `bfd_link_info' structure. + + The local symbols of the input files will not have been entered into +the linker hash table. The `_bfd_final_link' routine must consider +each input file and include the symbols in the output file. It may be +convenient to do this when looking through the `link_order' structures, +or it may be done by stepping through the `input_bfds' list. + + The `_bfd_final_link' routine must also traverse the global hash +table to gather all the externally visible symbols. It is possible +that most of the externally visible symbols may be written out when +considering the symbols of each input file, but it is still necessary +to traverse the hash table since the linker script may have defined +some symbols that are not in any of the input files. + + The `strip' field of the `bfd_link_info' structure controls which +symbols are written out. The possible values are listed in +`bfdlink.h'. If the value is `strip_some', then the `keep_hash' field +of the `bfd_link_info' structure is a hash table of symbols to keep; +each symbol should be looked up in this hash table, and only symbols +which are present should be included in the output file. + + If the `strip' field of the `bfd_link_info' structure permits local +symbols to be written out, the `discard' field is used to further +controls which local symbols are included in the output file. If the +value is `discard_l', then all local symbols which begin with a certain +prefix are discarded; this is controlled by the +`bfd_is_local_label_name' entry point. + + The a.out backend handles symbols by calling +`aout_link_write_symbols' on each input BFD and then traversing the +global hash table with the function `aout_link_write_other_symbol'. It +builds a string table while writing out the symbols, which is written +to the output file at the end of `NAME(aout,final_link)'. + +2.17.3.4 `bfd_link_split_section' +................................. + +*Synopsis* + bfd_boolean bfd_link_split_section (bfd *abfd, asection *sec); + *Description* +Return nonzero if SEC should be split during a reloceatable or final +link. + #define bfd_link_split_section(abfd, sec) \ + BFD_SEND (abfd, _bfd_link_split_section, (abfd, sec)) + +2.17.3.5 `bfd_section_already_linked' +..................................... + +*Synopsis* + void bfd_section_already_linked (bfd *abfd, asection *sec, + struct bfd_link_info *info); + *Description* +Check if SEC has been already linked during a reloceatable or final +link. + #define bfd_section_already_linked(abfd, sec, info) \ + BFD_SEND (abfd, _section_already_linked, (abfd, sec, info)) + +2.17.3.6 `bfd_generic_define_common_symbol' +........................................... + +*Synopsis* + bfd_boolean bfd_generic_define_common_symbol + (bfd *output_bfd, struct bfd_link_info *info, + struct bfd_link_hash_entry *h); + *Description* +Convert common symbol H into a defined symbol. Return TRUE on success +and FALSE on failure. + #define bfd_define_common_symbol(output_bfd, info, h) \ + BFD_SEND (output_bfd, _bfd_define_common_symbol, (output_bfd, info, h)) + +2.17.3.7 `bfd_find_version_for_sym ' +.................................... + +*Synopsis* + struct bfd_elf_version_tree * bfd_find_version_for_sym + (struct bfd_elf_version_tree *verdefs, + const char *sym_name, bfd_boolean *hide); + *Description* +Search an elf version script tree for symbol versioning info and export +/ don't-export status for a given symbol. Return non-NULL on success +and NULL on failure; also sets the output `hide' boolean parameter. + + +File: bfd.info, Node: Hash Tables, Prev: Linker Functions, Up: BFD front end + +2.18 Hash Tables +================ + +BFD provides a simple set of hash table functions. Routines are +provided to initialize a hash table, to free a hash table, to look up a +string in a hash table and optionally create an entry for it, and to +traverse a hash table. There is currently no routine to delete an +string from a hash table. + + The basic hash table does not permit any data to be stored with a +string. However, a hash table is designed to present a base class from +which other types of hash tables may be derived. These derived types +may store additional information with the string. Hash tables were +implemented in this way, rather than simply providing a data pointer in +a hash table entry, because they were designed for use by the linker +back ends. The linker may create thousands of hash table entries, and +the overhead of allocating private data and storing and following +pointers becomes noticeable. + + The basic hash table code is in `hash.c'. + +* Menu: + +* Creating and Freeing a Hash Table:: +* Looking Up or Entering a String:: +* Traversing a Hash Table:: +* Deriving a New Hash Table Type:: + + +File: bfd.info, Node: Creating and Freeing a Hash Table, Next: Looking Up or Entering a String, Prev: Hash Tables, Up: Hash Tables + +2.18.1 Creating and freeing a hash table +---------------------------------------- + +To create a hash table, create an instance of a `struct bfd_hash_table' +(defined in `bfd.h') and call `bfd_hash_table_init' (if you know +approximately how many entries you will need, the function +`bfd_hash_table_init_n', which takes a SIZE argument, may be used). +`bfd_hash_table_init' returns `FALSE' if some sort of error occurs. + + The function `bfd_hash_table_init' take as an argument a function to +use to create new entries. For a basic hash table, use the function +`bfd_hash_newfunc'. *Note Deriving a New Hash Table Type::, for why +you would want to use a different value for this argument. + + `bfd_hash_table_init' will create an objalloc which will be used to +allocate new entries. You may allocate memory on this objalloc using +`bfd_hash_allocate'. + + Use `bfd_hash_table_free' to free up all the memory that has been +allocated for a hash table. This will not free up the `struct +bfd_hash_table' itself, which you must provide. + + Use `bfd_hash_set_default_size' to set the default size of hash +table to use. + + +File: bfd.info, Node: Looking Up or Entering a String, Next: Traversing a Hash Table, Prev: Creating and Freeing a Hash Table, Up: Hash Tables + +2.18.2 Looking up or entering a string +-------------------------------------- + +The function `bfd_hash_lookup' is used both to look up a string in the +hash table and to create a new entry. + + If the CREATE argument is `FALSE', `bfd_hash_lookup' will look up a +string. If the string is found, it will returns a pointer to a `struct +bfd_hash_entry'. If the string is not found in the table +`bfd_hash_lookup' will return `NULL'. You should not modify any of the +fields in the returns `struct bfd_hash_entry'. + + If the CREATE argument is `TRUE', the string will be entered into +the hash table if it is not already there. Either way a pointer to a +`struct bfd_hash_entry' will be returned, either to the existing +structure or to a newly created one. In this case, a `NULL' return +means that an error occurred. + + If the CREATE argument is `TRUE', and a new entry is created, the +COPY argument is used to decide whether to copy the string onto the +hash table objalloc or not. If COPY is passed as `FALSE', you must be +careful not to deallocate or modify the string as long as the hash table +exists. + + +File: bfd.info, Node: Traversing a Hash Table, Next: Deriving a New Hash Table Type, Prev: Looking Up or Entering a String, Up: Hash Tables + +2.18.3 Traversing a hash table +------------------------------ + +The function `bfd_hash_traverse' may be used to traverse a hash table, +calling a function on each element. The traversal is done in a random +order. + + `bfd_hash_traverse' takes as arguments a function and a generic +`void *' pointer. The function is called with a hash table entry (a +`struct bfd_hash_entry *') and the generic pointer passed to +`bfd_hash_traverse'. The function must return a `boolean' value, which +indicates whether to continue traversing the hash table. If the +function returns `FALSE', `bfd_hash_traverse' will stop the traversal +and return immediately. + + +File: bfd.info, Node: Deriving a New Hash Table Type, Prev: Traversing a Hash Table, Up: Hash Tables + +2.18.4 Deriving a new hash table type +------------------------------------- + +Many uses of hash tables want to store additional information which +each entry in the hash table. Some also find it convenient to store +additional information with the hash table itself. This may be done +using a derived hash table. + + Since C is not an object oriented language, creating a derived hash +table requires sticking together some boilerplate routines with a few +differences specific to the type of hash table you want to create. + + An example of a derived hash table is the linker hash table. The +structures for this are defined in `bfdlink.h'. The functions are in +`linker.c'. + + You may also derive a hash table from an already derived hash table. +For example, the a.out linker backend code uses a hash table derived +from the linker hash table. + +* Menu: + +* Define the Derived Structures:: +* Write the Derived Creation Routine:: +* Write Other Derived Routines:: + + +File: bfd.info, Node: Define the Derived Structures, Next: Write the Derived Creation Routine, Prev: Deriving a New Hash Table Type, Up: Deriving a New Hash Table Type + +2.18.4.1 Define the derived structures +...................................... + +You must define a structure for an entry in the hash table, and a +structure for the hash table itself. + + The first field in the structure for an entry in the hash table must +be of the type used for an entry in the hash table you are deriving +from. If you are deriving from a basic hash table this is `struct +bfd_hash_entry', which is defined in `bfd.h'. The first field in the +structure for the hash table itself must be of the type of the hash +table you are deriving from itself. If you are deriving from a basic +hash table, this is `struct bfd_hash_table'. + + For example, the linker hash table defines `struct +bfd_link_hash_entry' (in `bfdlink.h'). The first field, `root', is of +type `struct bfd_hash_entry'. Similarly, the first field in `struct +bfd_link_hash_table', `table', is of type `struct bfd_hash_table'. + + +File: bfd.info, Node: Write the Derived Creation Routine, Next: Write Other Derived Routines, Prev: Define the Derived Structures, Up: Deriving a New Hash Table Type + +2.18.4.2 Write the derived creation routine +........................................... + +You must write a routine which will create and initialize an entry in +the hash table. This routine is passed as the function argument to +`bfd_hash_table_init'. + + In order to permit other hash tables to be derived from the hash +table you are creating, this routine must be written in a standard way. + + The first argument to the creation routine is a pointer to a hash +table entry. This may be `NULL', in which case the routine should +allocate the right amount of space. Otherwise the space has already +been allocated by a hash table type derived from this one. + + After allocating space, the creation routine must call the creation +routine of the hash table type it is derived from, passing in a pointer +to the space it just allocated. This will initialize any fields used +by the base hash table. + + Finally the creation routine must initialize any local fields for +the new hash table type. + + Here is a boilerplate example of a creation routine. FUNCTION_NAME +is the name of the routine. ENTRY_TYPE is the type of an entry in the +hash table you are creating. BASE_NEWFUNC is the name of the creation +routine of the hash table type your hash table is derived from. + + struct bfd_hash_entry * + FUNCTION_NAME (struct bfd_hash_entry *entry, + struct bfd_hash_table *table, + const char *string) + { + struct ENTRY_TYPE *ret = (ENTRY_TYPE *) entry; + + /* Allocate the structure if it has not already been allocated by a + derived class. */ + if (ret == NULL) + { + ret = bfd_hash_allocate (table, sizeof (* ret)); + if (ret == NULL) + return NULL; + } + + /* Call the allocation method of the base class. */ + ret = ((ENTRY_TYPE *) + BASE_NEWFUNC ((struct bfd_hash_entry *) ret, table, string)); + + /* Initialize the local fields here. */ + + return (struct bfd_hash_entry *) ret; + } + *Description* +The creation routine for the linker hash table, which is in `linker.c', +looks just like this example. FUNCTION_NAME is +`_bfd_link_hash_newfunc'. ENTRY_TYPE is `struct bfd_link_hash_entry'. +BASE_NEWFUNC is `bfd_hash_newfunc', the creation routine for a basic +hash table. + + `_bfd_link_hash_newfunc' also initializes the local fields in a +linker hash table entry: `type', `written' and `next'. + + +File: bfd.info, Node: Write Other Derived Routines, Prev: Write the Derived Creation Routine, Up: Deriving a New Hash Table Type + +2.18.4.3 Write other derived routines +..................................... + +You will want to write other routines for your new hash table, as well. + + You will want an initialization routine which calls the +initialization routine of the hash table you are deriving from and +initializes any other local fields. For the linker hash table, this is +`_bfd_link_hash_table_init' in `linker.c'. + + You will want a lookup routine which calls the lookup routine of the +hash table you are deriving from and casts the result. The linker hash +table uses `bfd_link_hash_lookup' in `linker.c' (this actually takes an +additional argument which it uses to decide how to return the looked up +value). + + You may want a traversal routine. This should just call the +traversal routine of the hash table you are deriving from with +appropriate casts. The linker hash table uses `bfd_link_hash_traverse' +in `linker.c'. + + These routines may simply be defined as macros. For example, the +a.out backend linker hash table, which is derived from the linker hash +table, uses macros for the lookup and traversal routines. These are +`aout_link_hash_lookup' and `aout_link_hash_traverse' in aoutx.h. + + +File: bfd.info, Node: BFD back ends, Next: GNU Free Documentation License, Prev: BFD front end, Up: Top + +3 BFD back ends +*************** + +* Menu: + +* What to Put Where:: +* aout :: a.out backends +* coff :: coff backends +* elf :: elf backends +* mmo :: mmo backend + + +File: bfd.info, Node: What to Put Where, Next: aout, Prev: BFD back ends, Up: BFD back ends + +3.1 What to Put Where +===================== + +All of BFD lives in one directory. + + +File: bfd.info, Node: aout, Next: coff, Prev: What to Put Where, Up: BFD back ends + +3.2 a.out backends +================== + +*Description* +BFD supports a number of different flavours of a.out format, though the +major differences are only the sizes of the structures on disk, and the +shape of the relocation information. + + The support is split into a basic support file `aoutx.h' and other +files which derive functions from the base. One derivation file is +`aoutf1.h' (for a.out flavour 1), and adds to the basic a.out functions +support for sun3, sun4, 386 and 29k a.out files, to create a target +jump vector for a specific target. + + This information is further split out into more specific files for +each machine, including `sunos.c' for sun3 and sun4, `newsos3.c' for +the Sony NEWS, and `demo64.c' for a demonstration of a 64 bit a.out +format. + + The base file `aoutx.h' defines general mechanisms for reading and +writing records to and from disk and various other methods which BFD +requires. It is included by `aout32.c' and `aout64.c' to form the names +`aout_32_swap_exec_header_in', `aout_64_swap_exec_header_in', etc. + + As an example, this is what goes on to make the back end for a sun4, +from `aout32.c': + + #define ARCH_SIZE 32 + #include "aoutx.h" + + Which exports names: + + ... + aout_32_canonicalize_reloc + aout_32_find_nearest_line + aout_32_get_lineno + aout_32_get_reloc_upper_bound + ... + + from `sunos.c': + + #define TARGET_NAME "a.out-sunos-big" + #define VECNAME sunos_big_vec + #include "aoutf1.h" + + requires all the names from `aout32.c', and produces the jump vector + + sunos_big_vec + + The file `host-aout.c' is a special case. It is for a large set of +hosts that use "more or less standard" a.out files, and for which +cross-debugging is not interesting. It uses the standard 32-bit a.out +support routines, but determines the file offsets and addresses of the +text, data, and BSS sections, the machine architecture and machine +type, and the entry point address, in a host-dependent manner. Once +these values have been determined, generic code is used to handle the +object file. + + When porting it to run on a new system, you must supply: + + HOST_PAGE_SIZE + HOST_SEGMENT_SIZE + HOST_MACHINE_ARCH (optional) + HOST_MACHINE_MACHINE (optional) + HOST_TEXT_START_ADDR + HOST_STACK_END_ADDR + + in the file `../include/sys/h-XXX.h' (for your host). These values, +plus the structures and macros defined in `a.out.h' on your host +system, will produce a BFD target that will access ordinary a.out files +on your host. To configure a new machine to use `host-aout.c', specify: + + TDEFAULTS = -DDEFAULT_VECTOR=host_aout_big_vec + TDEPFILES= host-aout.o trad-core.o + + in the `config/XXX.mt' file, and modify `configure.in' to use the +`XXX.mt' file (by setting "`bfd_target=XXX'") when your configuration +is selected. + +3.2.1 Relocations +----------------- + +*Description* +The file `aoutx.h' provides for both the _standard_ and _extended_ +forms of a.out relocation records. + + The standard records contain only an address, a symbol index, and a +type field. The extended records (used on 29ks and sparcs) also have a +full integer for an addend. + +3.2.2 Internal entry points +--------------------------- + +*Description* +`aoutx.h' exports several routines for accessing the contents of an +a.out file, which are gathered and exported in turn by various format +specific files (eg sunos.c). + +3.2.2.1 `aout_SIZE_swap_exec_header_in' +....................................... + +*Synopsis* + void aout_SIZE_swap_exec_header_in, + (bfd *abfd, + struct external_exec *bytes, + struct internal_exec *execp); + *Description* +Swap the information in an executable header RAW_BYTES taken from a raw +byte stream memory image into the internal exec header structure EXECP. + +3.2.2.2 `aout_SIZE_swap_exec_header_out' +........................................ + +*Synopsis* + void aout_SIZE_swap_exec_header_out + (bfd *abfd, + struct internal_exec *execp, + struct external_exec *raw_bytes); + *Description* +Swap the information in an internal exec header structure EXECP into +the buffer RAW_BYTES ready for writing to disk. + +3.2.2.3 `aout_SIZE_some_aout_object_p' +...................................... + +*Synopsis* + const bfd_target *aout_SIZE_some_aout_object_p + (bfd *abfd, + struct internal_exec *execp, + const bfd_target *(*callback_to_real_object_p) (bfd *)); + *Description* +Some a.out variant thinks that the file open in ABFD checking is an +a.out file. Do some more checking, and set up for access if it really +is. Call back to the calling environment's "finish up" function just +before returning, to handle any last-minute setup. + +3.2.2.4 `aout_SIZE_mkobject' +............................ + +*Synopsis* + bfd_boolean aout_SIZE_mkobject, (bfd *abfd); + *Description* +Initialize BFD ABFD for use with a.out files. + +3.2.2.5 `aout_SIZE_machine_type' +................................ + +*Synopsis* + enum machine_type aout_SIZE_machine_type + (enum bfd_architecture arch, + unsigned long machine, + bfd_boolean *unknown); + *Description* +Keep track of machine architecture and machine type for a.out's. Return +the `machine_type' for a particular architecture and machine, or +`M_UNKNOWN' if that exact architecture and machine can't be represented +in a.out format. + + If the architecture is understood, machine type 0 (default) is +always understood. + +3.2.2.6 `aout_SIZE_set_arch_mach' +................................. + +*Synopsis* + bfd_boolean aout_SIZE_set_arch_mach, + (bfd *, + enum bfd_architecture arch, + unsigned long machine); + *Description* +Set the architecture and the machine of the BFD ABFD to the values ARCH +and MACHINE. Verify that ABFD's format can support the architecture +required. + +3.2.2.7 `aout_SIZE_new_section_hook' +.................................... + +*Synopsis* + bfd_boolean aout_SIZE_new_section_hook, + (bfd *abfd, + asection *newsect); + *Description* +Called by the BFD in response to a `bfd_make_section' request. + + +File: bfd.info, Node: coff, Next: elf, Prev: aout, Up: BFD back ends + +3.3 coff backends +================= + +BFD supports a number of different flavours of coff format. The major +differences between formats are the sizes and alignments of fields in +structures on disk, and the occasional extra field. + + Coff in all its varieties is implemented with a few common files and +a number of implementation specific files. For example, The 88k bcs +coff format is implemented in the file `coff-m88k.c'. This file +`#include's `coff/m88k.h' which defines the external structure of the +coff format for the 88k, and `coff/internal.h' which defines the +internal structure. `coff-m88k.c' also defines the relocations used by +the 88k format *Note Relocations::. + + The Intel i960 processor version of coff is implemented in +`coff-i960.c'. This file has the same structure as `coff-m88k.c', +except that it includes `coff/i960.h' rather than `coff-m88k.h'. + +3.3.1 Porting to a new version of coff +-------------------------------------- + +The recommended method is to select from the existing implementations +the version of coff which is most like the one you want to use. For +example, we'll say that i386 coff is the one you select, and that your +coff flavour is called foo. Copy `i386coff.c' to `foocoff.c', copy +`../include/coff/i386.h' to `../include/coff/foo.h', and add the lines +to `targets.c' and `Makefile.in' so that your new back end is used. +Alter the shapes of the structures in `../include/coff/foo.h' so that +they match what you need. You will probably also have to add `#ifdef's +to the code in `coff/internal.h' and `coffcode.h' if your version of +coff is too wild. + + You can verify that your new BFD backend works quite simply by +building `objdump' from the `binutils' directory, and making sure that +its version of what's going on and your host system's idea (assuming it +has the pretty standard coff dump utility, usually called `att-dump' or +just `dump') are the same. Then clean up your code, and send what +you've done to Cygnus. Then your stuff will be in the next release, and +you won't have to keep integrating it. + +3.3.2 How the coff backend works +-------------------------------- + +3.3.2.1 File layout +................... + +The Coff backend is split into generic routines that are applicable to +any Coff target and routines that are specific to a particular target. +The target-specific routines are further split into ones which are +basically the same for all Coff targets except that they use the +external symbol format or use different values for certain constants. + + The generic routines are in `coffgen.c'. These routines work for +any Coff target. They use some hooks into the target specific code; +the hooks are in a `bfd_coff_backend_data' structure, one of which +exists for each target. + + The essentially similar target-specific routines are in +`coffcode.h'. This header file includes executable C code. The +various Coff targets first include the appropriate Coff header file, +make any special defines that are needed, and then include `coffcode.h'. + + Some of the Coff targets then also have additional routines in the +target source file itself. + + For example, `coff-i960.c' includes `coff/internal.h' and +`coff/i960.h'. It then defines a few constants, such as `I960', and +includes `coffcode.h'. Since the i960 has complex relocation types, +`coff-i960.c' also includes some code to manipulate the i960 relocs. +This code is not in `coffcode.h' because it would not be used by any +other target. + +3.3.2.2 Coff long section names +............................... + +In the standard Coff object format, section names are limited to the +eight bytes available in the `s_name' field of the `SCNHDR' section +header structure. The format requires the field to be NUL-padded, but +not necessarily NUL-terminated, so the longest section names permitted +are a full eight characters. + + The Microsoft PE variants of the Coff object file format add an +extension to support the use of long section names. This extension is +defined in section 4 of the Microsoft PE/COFF specification (rev 8.1). +If a section name is too long to fit into the section header's `s_name' +field, it is instead placed into the string table, and the `s_name' +field is filled with a slash ("/") followed by the ASCII decimal +representation of the offset of the full name relative to the string +table base. + + Note that this implies that the extension can only be used in object +files, as executables do not contain a string table. The standard +specifies that long section names from objects emitted into executable +images are to be truncated. + + However, as a GNU extension, BFD can generate executable images that +contain a string table and long section names. This would appear to be +technically valid, as the standard only says that Coff debugging +information is deprecated, not forbidden, and in practice it works, +although some tools that parse PE files expecting the MS standard +format may become confused; `PEview' is one known example. + + The functionality is supported in BFD by code implemented under the +control of the macro `COFF_LONG_SECTION_NAMES'. If not defined, the +format does not support long section names in any way. If defined, it +is used to initialise a flag, `_bfd_coff_long_section_names', and a +hook function pointer, `_bfd_coff_set_long_section_names', in the Coff +backend data structure. The flag controls the generation of long +section names in output BFDs at runtime; if it is false, as it will be +by default when generating an executable image, long section names are +truncated; if true, the long section names extension is employed. The +hook points to a function that allows the value of the flag to be +altered at runtime, on formats that support long section names at all; +on other formats it points to a stub that returns an error indication. +With input BFDs, the flag is set according to whether any long section +names are detected while reading the section headers. For a completely +new BFD, the flag is set to the default for the target format. This +information can be used by a client of the BFD library when deciding +what output format to generate, and means that a BFD that is opened for +read and subsequently converted to a writeable BFD and modified +in-place will retain whatever format it had on input. + + If `COFF_LONG_SECTION_NAMES' is simply defined (blank), or is +defined to the value "1", then long section names are enabled by +default; if it is defined to the value zero, they are disabled by +default (but still accepted in input BFDs). The header `coffcode.h' +defines a macro, `COFF_DEFAULT_LONG_SECTION_NAMES', which is used in +the backends to initialise the backend data structure fields +appropriately; see the comments for further detail. + +3.3.2.3 Bit twiddling +..................... + +Each flavour of coff supported in BFD has its own header file +describing the external layout of the structures. There is also an +internal description of the coff layout, in `coff/internal.h'. A major +function of the coff backend is swapping the bytes and twiddling the +bits to translate the external form of the structures into the normal +internal form. This is all performed in the `bfd_swap'_thing_direction +routines. Some elements are different sizes between different versions +of coff; it is the duty of the coff version specific include file to +override the definitions of various packing routines in `coffcode.h'. +E.g., the size of line number entry in coff is sometimes 16 bits, and +sometimes 32 bits. `#define'ing `PUT_LNSZ_LNNO' and `GET_LNSZ_LNNO' +will select the correct one. No doubt, some day someone will find a +version of coff which has a varying field size not catered to at the +moment. To port BFD, that person will have to add more `#defines'. +Three of the bit twiddling routines are exported to `gdb'; +`coff_swap_aux_in', `coff_swap_sym_in' and `coff_swap_lineno_in'. `GDB' +reads the symbol table on its own, but uses BFD to fix things up. More +of the bit twiddlers are exported for `gas'; `coff_swap_aux_out', +`coff_swap_sym_out', `coff_swap_lineno_out', `coff_swap_reloc_out', +`coff_swap_filehdr_out', `coff_swap_aouthdr_out', +`coff_swap_scnhdr_out'. `Gas' currently keeps track of all the symbol +table and reloc drudgery itself, thereby saving the internal BFD +overhead, but uses BFD to swap things on the way out, making cross +ports much safer. Doing so also allows BFD (and thus the linker) to +use the same header files as `gas', which makes one avenue to disaster +disappear. + +3.3.2.4 Symbol reading +...................... + +The simple canonical form for symbols used by BFD is not rich enough to +keep all the information available in a coff symbol table. The back end +gets around this problem by keeping the original symbol table around, +"behind the scenes". + + When a symbol table is requested (through a call to +`bfd_canonicalize_symtab'), a request gets through to +`coff_get_normalized_symtab'. This reads the symbol table from the coff +file and swaps all the structures inside into the internal form. It +also fixes up all the pointers in the table (represented in the file by +offsets from the first symbol in the table) into physical pointers to +elements in the new internal table. This involves some work since the +meanings of fields change depending upon context: a field that is a +pointer to another structure in the symbol table at one moment may be +the size in bytes of a structure at the next. Another pass is made +over the table. All symbols which mark file names (`C_FILE' symbols) +are modified so that the internal string points to the value in the +auxent (the real filename) rather than the normal text associated with +the symbol (`".file"'). + + At this time the symbol names are moved around. Coff stores all +symbols less than nine characters long physically within the symbol +table; longer strings are kept at the end of the file in the string +table. This pass moves all strings into memory and replaces them with +pointers to the strings. + + The symbol table is massaged once again, this time to create the +canonical table used by the BFD application. Each symbol is inspected +in turn, and a decision made (using the `sclass' field) about the +various flags to set in the `asymbol'. *Note Symbols::. The generated +canonical table shares strings with the hidden internal symbol table. + + Any linenumbers are read from the coff file too, and attached to the +symbols which own the functions the linenumbers belong to. + +3.3.2.5 Symbol writing +...................... + +Writing a symbol to a coff file which didn't come from a coff file will +lose any debugging information. The `asymbol' structure remembers the +BFD from which the symbol was taken, and on output the back end makes +sure that the same destination target as source target is present. + + When the symbols have come from a coff file then all the debugging +information is preserved. + + Symbol tables are provided for writing to the back end in a vector +of pointers to pointers. This allows applications like the linker to +accumulate and output large symbol tables without having to do too much +byte copying. + + This function runs through the provided symbol table and patches +each symbol marked as a file place holder (`C_FILE') to point to the +next file place holder in the list. It also marks each `offset' field +in the list with the offset from the first symbol of the current symbol. + + Another function of this procedure is to turn the canonical value +form of BFD into the form used by coff. Internally, BFD expects symbol +values to be offsets from a section base; so a symbol physically at +0x120, but in a section starting at 0x100, would have the value 0x20. +Coff expects symbols to contain their final value, so symbols have +their values changed at this point to reflect their sum with their +owning section. This transformation uses the `output_section' field of +the `asymbol''s `asection' *Note Sections::. + + * `coff_mangle_symbols' + This routine runs though the provided symbol table and uses the +offsets generated by the previous pass and the pointers generated when +the symbol table was read in to create the structured hierarchy +required by coff. It changes each pointer to a symbol into the index +into the symbol table of the asymbol. + + * `coff_write_symbols' + This routine runs through the symbol table and patches up the +symbols from their internal form into the coff way, calls the bit +twiddlers, and writes out the table to the file. + +3.3.2.6 `coff_symbol_type' +.......................... + +*Description* +The hidden information for an `asymbol' is described in a +`combined_entry_type': + + + typedef struct coff_ptr_struct + { + /* Remembers the offset from the first symbol in the file for + this symbol. Generated by coff_renumber_symbols. */ + unsigned int offset; + + /* Should the value of this symbol be renumbered. Used for + XCOFF C_BSTAT symbols. Set by coff_slurp_symbol_table. */ + unsigned int fix_value : 1; + + /* Should the tag field of this symbol be renumbered. + Created by coff_pointerize_aux. */ + unsigned int fix_tag : 1; + + /* Should the endidx field of this symbol be renumbered. + Created by coff_pointerize_aux. */ + unsigned int fix_end : 1; + + /* Should the x_csect.x_scnlen field be renumbered. + Created by coff_pointerize_aux. */ + unsigned int fix_scnlen : 1; + + /* Fix up an XCOFF C_BINCL/C_EINCL symbol. The value is the + index into the line number entries. Set by coff_slurp_symbol_table. */ + unsigned int fix_line : 1; + + /* The container for the symbol structure as read and translated + from the file. */ + union + { + union internal_auxent auxent; + struct internal_syment syment; + } u; + } combined_entry_type; + + + /* Each canonical asymbol really looks like this: */ + + typedef struct coff_symbol_struct + { + /* The actual symbol which the rest of BFD works with */ + asymbol symbol; + + /* A pointer to the hidden information for this symbol */ + combined_entry_type *native; + + /* A pointer to the linenumber information for this symbol */ + struct lineno_cache_entry *lineno; + + /* Have the line numbers been relocated yet ? */ + bfd_boolean done_lineno; + } coff_symbol_type; + +3.3.2.7 `bfd_coff_backend_data' +............................... + + /* COFF symbol classifications. */ + + enum coff_symbol_classification + { + /* Global symbol. */ + COFF_SYMBOL_GLOBAL, + /* Common symbol. */ + COFF_SYMBOL_COMMON, + /* Undefined symbol. */ + COFF_SYMBOL_UNDEFINED, + /* Local symbol. */ + COFF_SYMBOL_LOCAL, + /* PE section symbol. */ + COFF_SYMBOL_PE_SECTION + }; +Special entry points for gdb to swap in coff symbol table parts: + typedef struct + { + void (*_bfd_coff_swap_aux_in) + (bfd *, void *, int, int, int, int, void *); + + void (*_bfd_coff_swap_sym_in) + (bfd *, void *, void *); + + void (*_bfd_coff_swap_lineno_in) + (bfd *, void *, void *); + + unsigned int (*_bfd_coff_swap_aux_out) + (bfd *, void *, int, int, int, int, void *); + + unsigned int (*_bfd_coff_swap_sym_out) + (bfd *, void *, void *); + + unsigned int (*_bfd_coff_swap_lineno_out) + (bfd *, void *, void *); + + unsigned int (*_bfd_coff_swap_reloc_out) + (bfd *, void *, void *); + + unsigned int (*_bfd_coff_swap_filehdr_out) + (bfd *, void *, void *); + + unsigned int (*_bfd_coff_swap_aouthdr_out) + (bfd *, void *, void *); + + unsigned int (*_bfd_coff_swap_scnhdr_out) + (bfd *, void *, void *); + + unsigned int _bfd_filhsz; + unsigned int _bfd_aoutsz; + unsigned int _bfd_scnhsz; + unsigned int _bfd_symesz; + unsigned int _bfd_auxesz; + unsigned int _bfd_relsz; + unsigned int _bfd_linesz; + unsigned int _bfd_filnmlen; + bfd_boolean _bfd_coff_long_filenames; + + bfd_boolean _bfd_coff_long_section_names; + bfd_boolean (*_bfd_coff_set_long_section_names) + (bfd *, int); + + unsigned int _bfd_coff_default_section_alignment_power; + bfd_boolean _bfd_coff_force_symnames_in_strings; + unsigned int _bfd_coff_debug_string_prefix_length; + + void (*_bfd_coff_swap_filehdr_in) + (bfd *, void *, void *); + + void (*_bfd_coff_swap_aouthdr_in) + (bfd *, void *, void *); + + void (*_bfd_coff_swap_scnhdr_in) + (bfd *, void *, void *); + + void (*_bfd_coff_swap_reloc_in) + (bfd *abfd, void *, void *); + + bfd_boolean (*_bfd_coff_bad_format_hook) + (bfd *, void *); + + bfd_boolean (*_bfd_coff_set_arch_mach_hook) + (bfd *, void *); + + void * (*_bfd_coff_mkobject_hook) + (bfd *, void *, void *); + + bfd_boolean (*_bfd_styp_to_sec_flags_hook) + (bfd *, void *, const char *, asection *, flagword *); + + void (*_bfd_set_alignment_hook) + (bfd *, asection *, void *); + + bfd_boolean (*_bfd_coff_slurp_symbol_table) + (bfd *); + + bfd_boolean (*_bfd_coff_symname_in_debug) + (bfd *, struct internal_syment *); + + bfd_boolean (*_bfd_coff_pointerize_aux_hook) + (bfd *, combined_entry_type *, combined_entry_type *, + unsigned int, combined_entry_type *); + + bfd_boolean (*_bfd_coff_print_aux) + (bfd *, FILE *, combined_entry_type *, combined_entry_type *, + combined_entry_type *, unsigned int); + + void (*_bfd_coff_reloc16_extra_cases) + (bfd *, struct bfd_link_info *, struct bfd_link_order *, arelent *, + bfd_byte *, unsigned int *, unsigned int *); + + int (*_bfd_coff_reloc16_estimate) + (bfd *, asection *, arelent *, unsigned int, + struct bfd_link_info *); + + enum coff_symbol_classification (*_bfd_coff_classify_symbol) + (bfd *, struct internal_syment *); + + bfd_boolean (*_bfd_coff_compute_section_file_positions) + (bfd *); + + bfd_boolean (*_bfd_coff_start_final_link) + (bfd *, struct bfd_link_info *); + + bfd_boolean (*_bfd_coff_relocate_section) + (bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *, + struct internal_reloc *, struct internal_syment *, asection **); + + reloc_howto_type *(*_bfd_coff_rtype_to_howto) + (bfd *, asection *, struct internal_reloc *, + struct coff_link_hash_entry *, struct internal_syment *, + bfd_vma *); + + bfd_boolean (*_bfd_coff_adjust_symndx) + (bfd *, struct bfd_link_info *, bfd *, asection *, + struct internal_reloc *, bfd_boolean *); + + bfd_boolean (*_bfd_coff_link_add_one_symbol) + (struct bfd_link_info *, bfd *, const char *, flagword, + asection *, bfd_vma, const char *, bfd_boolean, bfd_boolean, + struct bfd_link_hash_entry **); + + bfd_boolean (*_bfd_coff_link_output_has_begun) + (bfd *, struct coff_final_link_info *); + + bfd_boolean (*_bfd_coff_final_link_postscript) + (bfd *, struct coff_final_link_info *); + + bfd_boolean (*_bfd_coff_print_pdata) + (bfd *, void *); + + } bfd_coff_backend_data; + + #define coff_backend_info(abfd) \ + ((bfd_coff_backend_data *) (abfd)->xvec->backend_data) + + #define bfd_coff_swap_aux_in(a,e,t,c,ind,num,i) \ + ((coff_backend_info (a)->_bfd_coff_swap_aux_in) (a,e,t,c,ind,num,i)) + + #define bfd_coff_swap_sym_in(a,e,i) \ + ((coff_backend_info (a)->_bfd_coff_swap_sym_in) (a,e,i)) + + #define bfd_coff_swap_lineno_in(a,e,i) \ + ((coff_backend_info ( a)->_bfd_coff_swap_lineno_in) (a,e,i)) + + #define bfd_coff_swap_reloc_out(abfd, i, o) \ + ((coff_backend_info (abfd)->_bfd_coff_swap_reloc_out) (abfd, i, o)) + + #define bfd_coff_swap_lineno_out(abfd, i, o) \ + ((coff_backend_info (abfd)->_bfd_coff_swap_lineno_out) (abfd, i, o)) + + #define bfd_coff_swap_aux_out(a,i,t,c,ind,num,o) \ + ((coff_backend_info (a)->_bfd_coff_swap_aux_out) (a,i,t,c,ind,num,o)) + + #define bfd_coff_swap_sym_out(abfd, i,o) \ + ((coff_backend_info (abfd)->_bfd_coff_swap_sym_out) (abfd, i, o)) + + #define bfd_coff_swap_scnhdr_out(abfd, i,o) \ + ((coff_backend_info (abfd)->_bfd_coff_swap_scnhdr_out) (abfd, i, o)) + + #define bfd_coff_swap_filehdr_out(abfd, i,o) \ + ((coff_backend_info (abfd)->_bfd_coff_swap_filehdr_out) (abfd, i, o)) + + #define bfd_coff_swap_aouthdr_out(abfd, i,o) \ + ((coff_backend_info (abfd)->_bfd_coff_swap_aouthdr_out) (abfd, i, o)) + + #define bfd_coff_filhsz(abfd) (coff_backend_info (abfd)->_bfd_filhsz) + #define bfd_coff_aoutsz(abfd) (coff_backend_info (abfd)->_bfd_aoutsz) + #define bfd_coff_scnhsz(abfd) (coff_backend_info (abfd)->_bfd_scnhsz) + #define bfd_coff_symesz(abfd) (coff_backend_info (abfd)->_bfd_symesz) + #define bfd_coff_auxesz(abfd) (coff_backend_info (abfd)->_bfd_auxesz) + #define bfd_coff_relsz(abfd) (coff_backend_info (abfd)->_bfd_relsz) + #define bfd_coff_linesz(abfd) (coff_backend_info (abfd)->_bfd_linesz) + #define bfd_coff_filnmlen(abfd) (coff_backend_info (abfd)->_bfd_filnmlen) + #define bfd_coff_long_filenames(abfd) \ + (coff_backend_info (abfd)->_bfd_coff_long_filenames) + #define bfd_coff_long_section_names(abfd) \ + (coff_backend_info (abfd)->_bfd_coff_long_section_names) + #define bfd_coff_set_long_section_names(abfd, enable) \ + ((coff_backend_info (abfd)->_bfd_coff_set_long_section_names) (abfd, enable)) + #define bfd_coff_default_section_alignment_power(abfd) \ + (coff_backend_info (abfd)->_bfd_coff_default_section_alignment_power) + #define bfd_coff_swap_filehdr_in(abfd, i,o) \ + ((coff_backend_info (abfd)->_bfd_coff_swap_filehdr_in) (abfd, i, o)) + + #define bfd_coff_swap_aouthdr_in(abfd, i,o) \ + ((coff_backend_info (abfd)->_bfd_coff_swap_aouthdr_in) (abfd, i, o)) + + #define bfd_coff_swap_scnhdr_in(abfd, i,o) \ + ((coff_backend_info (abfd)->_bfd_coff_swap_scnhdr_in) (abfd, i, o)) + + #define bfd_coff_swap_reloc_in(abfd, i, o) \ + ((coff_backend_info (abfd)->_bfd_coff_swap_reloc_in) (abfd, i, o)) + + #define bfd_coff_bad_format_hook(abfd, filehdr) \ + ((coff_backend_info (abfd)->_bfd_coff_bad_format_hook) (abfd, filehdr)) + + #define bfd_coff_set_arch_mach_hook(abfd, filehdr)\ + ((coff_backend_info (abfd)->_bfd_coff_set_arch_mach_hook) (abfd, filehdr)) + #define bfd_coff_mkobject_hook(abfd, filehdr, aouthdr)\ + ((coff_backend_info (abfd)->_bfd_coff_mkobject_hook)\ + (abfd, filehdr, aouthdr)) + + #define bfd_coff_styp_to_sec_flags_hook(abfd, scnhdr, name, section, flags_ptr)\ + ((coff_backend_info (abfd)->_bfd_styp_to_sec_flags_hook)\ + (abfd, scnhdr, name, section, flags_ptr)) + + #define bfd_coff_set_alignment_hook(abfd, sec, scnhdr)\ + ((coff_backend_info (abfd)->_bfd_set_alignment_hook) (abfd, sec, scnhdr)) + + #define bfd_coff_slurp_symbol_table(abfd)\ + ((coff_backend_info (abfd)->_bfd_coff_slurp_symbol_table) (abfd)) + + #define bfd_coff_symname_in_debug(abfd, sym)\ + ((coff_backend_info (abfd)->_bfd_coff_symname_in_debug) (abfd, sym)) + + #define bfd_coff_force_symnames_in_strings(abfd)\ + (coff_backend_info (abfd)->_bfd_coff_force_symnames_in_strings) + + #define bfd_coff_debug_string_prefix_length(abfd)\ + (coff_backend_info (abfd)->_bfd_coff_debug_string_prefix_length) + + #define bfd_coff_print_aux(abfd, file, base, symbol, aux, indaux)\ + ((coff_backend_info (abfd)->_bfd_coff_print_aux)\ + (abfd, file, base, symbol, aux, indaux)) + + #define bfd_coff_reloc16_extra_cases(abfd, link_info, link_order,\ + reloc, data, src_ptr, dst_ptr)\ + ((coff_backend_info (abfd)->_bfd_coff_reloc16_extra_cases)\ + (abfd, link_info, link_order, reloc, data, src_ptr, dst_ptr)) + + #define bfd_coff_reloc16_estimate(abfd, section, reloc, shrink, link_info)\ + ((coff_backend_info (abfd)->_bfd_coff_reloc16_estimate)\ + (abfd, section, reloc, shrink, link_info)) + + #define bfd_coff_classify_symbol(abfd, sym)\ + ((coff_backend_info (abfd)->_bfd_coff_classify_symbol)\ + (abfd, sym)) + + #define bfd_coff_compute_section_file_positions(abfd)\ + ((coff_backend_info (abfd)->_bfd_coff_compute_section_file_positions)\ + (abfd)) + + #define bfd_coff_start_final_link(obfd, info)\ + ((coff_backend_info (obfd)->_bfd_coff_start_final_link)\ + (obfd, info)) + #define bfd_coff_relocate_section(obfd,info,ibfd,o,con,rel,isyms,secs)\ + ((coff_backend_info (ibfd)->_bfd_coff_relocate_section)\ + (obfd, info, ibfd, o, con, rel, isyms, secs)) + #define bfd_coff_rtype_to_howto(abfd, sec, rel, h, sym, addendp)\ + ((coff_backend_info (abfd)->_bfd_coff_rtype_to_howto)\ + (abfd, sec, rel, h, sym, addendp)) + #define bfd_coff_adjust_symndx(obfd, info, ibfd, sec, rel, adjustedp)\ + ((coff_backend_info (abfd)->_bfd_coff_adjust_symndx)\ + (obfd, info, ibfd, sec, rel, adjustedp)) + #define bfd_coff_link_add_one_symbol(info, abfd, name, flags, section,\ + value, string, cp, coll, hashp)\ + ((coff_backend_info (abfd)->_bfd_coff_link_add_one_symbol)\ + (info, abfd, name, flags, section, value, string, cp, coll, hashp)) + + #define bfd_coff_link_output_has_begun(a,p) \ + ((coff_backend_info (a)->_bfd_coff_link_output_has_begun) (a, p)) + #define bfd_coff_final_link_postscript(a,p) \ + ((coff_backend_info (a)->_bfd_coff_final_link_postscript) (a, p)) + + #define bfd_coff_have_print_pdata(a) \ + (coff_backend_info (a)->_bfd_coff_print_pdata) + #define bfd_coff_print_pdata(a,p) \ + ((coff_backend_info (a)->_bfd_coff_print_pdata) (a, p)) + + /* Macro: Returns true if the bfd is a PE executable as opposed to a + PE object file. */ + #define bfd_pei_p(abfd) \ + (CONST_STRNEQ ((abfd)->xvec->name, "pei-")) + +3.3.2.8 Writing relocations +........................... + +To write relocations, the back end steps though the canonical +relocation table and create an `internal_reloc'. The symbol index to +use is removed from the `offset' field in the symbol table supplied. +The address comes directly from the sum of the section base address and +the relocation offset; the type is dug directly from the howto field. +Then the `internal_reloc' is swapped into the shape of an +`external_reloc' and written out to disk. + +3.3.2.9 Reading linenumbers +........................... + +Creating the linenumber table is done by reading in the entire coff +linenumber table, and creating another table for internal use. + + A coff linenumber table is structured so that each function is +marked as having a line number of 0. Each line within the function is +an offset from the first line in the function. The base of the line +number information for the table is stored in the symbol associated +with the function. + + Note: The PE format uses line number 0 for a flag indicating a new +source file. + + The information is copied from the external to the internal table, +and each symbol which marks a function is marked by pointing its... + + How does this work ? + +3.3.2.10 Reading relocations +............................ + +Coff relocations are easily transformed into the internal BFD form +(`arelent'). + + Reading a coff relocation table is done in the following stages: + + * Read the entire coff relocation table into memory. + + * Process each relocation in turn; first swap it from the external + to the internal form. + + * Turn the symbol referenced in the relocation's symbol index into a + pointer into the canonical symbol table. This table is the same + as the one returned by a call to `bfd_canonicalize_symtab'. The + back end will call that routine and save the result if a + canonicalization hasn't been done. + + * The reloc index is turned into a pointer to a howto structure, in + a back end specific way. For instance, the 386 and 960 use the + `r_type' to directly produce an index into a howto table vector; + the 88k subtracts a number from the `r_type' field and creates an + addend field. + + +File: bfd.info, Node: elf, Next: mmo, Prev: coff, Up: BFD back ends + +3.4 ELF backends +================ + +BFD support for ELF formats is being worked on. Currently, the best +supported back ends are for sparc and i386 (running svr4 or Solaris 2). + + Documentation of the internals of the support code still needs to be +written. The code is changing quickly enough that we haven't bothered +yet. + + +File: bfd.info, Node: mmo, Prev: elf, Up: BFD back ends + +3.5 mmo backend +=============== + +The mmo object format is used exclusively together with Professor +Donald E. Knuth's educational 64-bit processor MMIX. The simulator +`mmix' which is available at +`http://www-cs-faculty.stanford.edu/~knuth/programs/mmix.tar.gz' +understands this format. That package also includes a combined +assembler and linker called `mmixal'. The mmo format has no advantages +feature-wise compared to e.g. ELF. It is a simple non-relocatable +object format with no support for archives or debugging information, +except for symbol value information and line numbers (which is not yet +implemented in BFD). See +`http://www-cs-faculty.stanford.edu/~knuth/mmix.html' for more +information about MMIX. The ELF format is used for intermediate object +files in the BFD implementation. + +* Menu: + +* File layout:: +* Symbol-table:: +* mmo section mapping:: + + +File: bfd.info, Node: File layout, Next: Symbol-table, Prev: mmo, Up: mmo + +3.5.1 File layout +----------------- + +The mmo file contents is not partitioned into named sections as with +e.g. ELF. Memory areas is formed by specifying the location of the +data that follows. Only the memory area `0x0000...00' to `0x01ff...ff' +is executable, so it is used for code (and constants) and the area +`0x2000...00' to `0x20ff...ff' is used for writable data. *Note mmo +section mapping::. + + There is provision for specifying "special data" of 65536 different +types. We use type 80 (decimal), arbitrarily chosen the same as the +ELF `e_machine' number for MMIX, filling it with section information +normally found in ELF objects. *Note mmo section mapping::. + + Contents is entered as 32-bit words, xor:ed over previous contents, +always zero-initialized. A word that starts with the byte `0x98' forms +a command called a `lopcode', where the next byte distinguished between +the thirteen lopcodes. The two remaining bytes, called the `Y' and `Z' +fields, or the `YZ' field (a 16-bit big-endian number), are used for +various purposes different for each lopcode. As documented in +`http://www-cs-faculty.stanford.edu/~knuth/mmixal-intro.ps.gz', the +lopcodes are: + +`lop_quote' + 0x98000001. The next word is contents, regardless of whether it + starts with 0x98 or not. + +`lop_loc' + 0x9801YYZZ, where `Z' is 1 or 2. This is a location directive, + setting the location for the next data to the next 32-bit word + (for Z = 1) or 64-bit word (for Z = 2), plus Y * 2^56. Normally + `Y' is 0 for the text segment and 2 for the data segment. + +`lop_skip' + 0x9802YYZZ. Increase the current location by `YZ' bytes. + +`lop_fixo' + 0x9803YYZZ, where `Z' is 1 or 2. Store the current location as 64 + bits into the location pointed to by the next 32-bit (Z = 1) or + 64-bit (Z = 2) word, plus Y * 2^56. + +`lop_fixr' + 0x9804YYZZ. `YZ' is stored into the current location plus 2 - 4 * + YZ. + +`lop_fixrx' + 0x980500ZZ. `Z' is 16 or 24. A value `L' derived from the + following 32-bit word are used in a manner similar to `YZ' in + lop_fixr: it is xor:ed into the current location minus 4 * L. The + first byte of the word is 0 or 1. If it is 1, then L = (LOWEST 24 + BITS OF WORD) - 2^Z, if 0, then L = (LOWEST 24 BITS OF WORD). + +`lop_file' + 0x9806YYZZ. `Y' is the file number, `Z' is count of 32-bit words. + Set the file number to `Y' and the line counter to 0. The next Z + * 4 bytes contain the file name, padded with zeros if the count is + not a multiple of four. The same `Y' may occur multiple times, + but `Z' must be 0 for all but the first occurrence. + +`lop_line' + 0x9807YYZZ. `YZ' is the line number. Together with lop_file, it + forms the source location for the next 32-bit word. Note that for + each non-lopcode 32-bit word, line numbers are assumed incremented + by one. + +`lop_spec' + 0x9808YYZZ. `YZ' is the type number. Data until the next lopcode + other than lop_quote forms special data of type `YZ'. *Note mmo + section mapping::. + + Other types than 80, (or type 80 with a content that does not + parse) is stored in sections named `.MMIX.spec_data.N' where N is + the `YZ'-type. The flags for such a sections say not to allocate + or load the data. The vma is 0. Contents of multiple occurrences + of special data N is concatenated to the data of the previous + lop_spec Ns. The location in data or code at which the lop_spec + occurred is lost. + +`lop_pre' + 0x980901ZZ. The first lopcode in a file. The `Z' field forms the + length of header information in 32-bit words, where the first word + tells the time in seconds since `00:00:00 GMT Jan 1 1970'. + +`lop_post' + 0x980a00ZZ. Z > 32. This lopcode follows after all + content-generating lopcodes in a program. The `Z' field denotes + the value of `rG' at the beginning of the program. The following + 256 - Z big-endian 64-bit words are loaded into global registers + `$G' ... `$255'. + +`lop_stab' + 0x980b0000. The next-to-last lopcode in a program. Must follow + immediately after the lop_post lopcode and its data. After this + lopcode follows all symbols in a compressed format (*note + Symbol-table::). + +`lop_end' + 0x980cYYZZ. The last lopcode in a program. It must follow the + lop_stab lopcode and its data. The `YZ' field contains the number + of 32-bit words of symbol table information after the preceding + lop_stab lopcode. + + Note that the lopcode "fixups"; `lop_fixr', `lop_fixrx' and +`lop_fixo' are not generated by BFD, but are handled. They are +generated by `mmixal'. + + This trivial one-label, one-instruction file: + + :Main TRAP 1,2,3 + + can be represented this way in mmo: + + 0x98090101 - lop_pre, one 32-bit word with timestamp. + <timestamp> + 0x98010002 - lop_loc, text segment, using a 64-bit address. + Note that mmixal does not emit this for the file above. + 0x00000000 - Address, high 32 bits. + 0x00000000 - Address, low 32 bits. + 0x98060002 - lop_file, 2 32-bit words for file-name. + 0x74657374 - "test" + 0x2e730000 - ".s\0\0" + 0x98070001 - lop_line, line 1. + 0x00010203 - TRAP 1,2,3 + 0x980a00ff - lop_post, setting $255 to 0. + 0x00000000 + 0x00000000 + 0x980b0000 - lop_stab for ":Main" = 0, serial 1. + 0x203a4040 *Note Symbol-table::. + 0x10404020 + 0x4d206120 + 0x69016e00 + 0x81000000 + 0x980c0005 - lop_end; symbol table contained five 32-bit words. + + +File: bfd.info, Node: Symbol-table, Next: mmo section mapping, Prev: File layout, Up: mmo + +3.5.2 Symbol table format +------------------------- + +From mmixal.w (or really, the generated mmixal.tex) in +`http://www-cs-faculty.stanford.edu/~knuth/programs/mmix.tar.gz'): +"Symbols are stored and retrieved by means of a `ternary search trie', +following ideas of Bentley and Sedgewick. (See ACM-SIAM Symp. on +Discrete Algorithms `8' (1997), 360-369; R.Sedgewick, `Algorithms in C' +(Reading, Mass. Addison-Wesley, 1998), `15.4'.) Each trie node stores +a character, and there are branches to subtries for the cases where a +given character is less than, equal to, or greater than the character +in the trie. There also is a pointer to a symbol table entry if a +symbol ends at the current node." + + So it's a tree encoded as a stream of bytes. The stream of bytes +acts on a single virtual global symbol, adding and removing characters +and signalling complete symbol points. Here, we read the stream and +create symbols at the completion points. + + First, there's a control byte `m'. If any of the listed bits in `m' +is nonzero, we execute what stands at the right, in the listed order: + + (MMO3_LEFT) + 0x40 - Traverse left trie. + (Read a new command byte and recurse.) + + (MMO3_SYMBITS) + 0x2f - Read the next byte as a character and store it in the + current character position; increment character position. + Test the bits of `m': + + (MMO3_WCHAR) + 0x80 - The character is 16-bit (so read another byte, + merge into current character. + + (MMO3_TYPEBITS) + 0xf - We have a complete symbol; parse the type, value + and serial number and do what should be done + with a symbol. The type and length information + is in j = (m & 0xf). + + (MMO3_REGQUAL_BITS) + j == 0xf: A register variable. The following + byte tells which register. + j <= 8: An absolute symbol. Read j bytes as the + big-endian number the symbol equals. + A j = 2 with two zero bytes denotes an + unknown symbol. + j > 8: As with j <= 8, but add (0x20 << 56) + to the value in the following j - 8 + bytes. + + Then comes the serial number, as a variant of + uleb128, but better named ubeb128: + Read bytes and shift the previous value left 7 + (multiply by 128). Add in the new byte, repeat + until a byte has bit 7 set. The serial number + is the computed value minus 128. + + (MMO3_MIDDLE) + 0x20 - Traverse middle trie. (Read a new command byte + and recurse.) Decrement character position. + + (MMO3_RIGHT) + 0x10 - Traverse right trie. (Read a new command byte and + recurse.) + + Let's look again at the `lop_stab' for the trivial file (*note File +layout::). + + 0x980b0000 - lop_stab for ":Main" = 0, serial 1. + 0x203a4040 + 0x10404020 + 0x4d206120 + 0x69016e00 + 0x81000000 + + This forms the trivial trie (note that the path between ":" and "M" +is redundant): + + 203a ":" + 40 / + 40 / + 10 \ + 40 / + 40 / + 204d "M" + 2061 "a" + 2069 "i" + 016e "n" is the last character in a full symbol, and + with a value represented in one byte. + 00 The value is 0. + 81 The serial number is 1. + + +File: bfd.info, Node: mmo section mapping, Prev: Symbol-table, Up: mmo + +3.5.3 mmo section mapping +------------------------- + +The implementation in BFD uses special data type 80 (decimal) to +encapsulate and describe named sections, containing e.g. debug +information. If needed, any datum in the encapsulation will be quoted +using lop_quote. First comes a 32-bit word holding the number of +32-bit words containing the zero-terminated zero-padded segment name. +After the name there's a 32-bit word holding flags describing the +section type. Then comes a 64-bit big-endian word with the section +length (in bytes), then another with the section start address. +Depending on the type of section, the contents might follow, +zero-padded to 32-bit boundary. For a loadable section (such as data +or code), the contents might follow at some later point, not +necessarily immediately, as a lop_loc with the same start address as in +the section description, followed by the contents. This in effect +forms a descriptor that must be emitted before the actual contents. +Sections described this way must not overlap. + + For areas that don't have such descriptors, synthetic sections are +formed by BFD. Consecutive contents in the two memory areas +`0x0000...00' to `0x01ff...ff' and `0x2000...00' to `0x20ff...ff' are +entered in sections named `.text' and `.data' respectively. If an area +is not otherwise described, but would together with a neighboring lower +area be less than `0x40000000' bytes long, it is joined with the lower +area and the gap is zero-filled. For other cases, a new section is +formed, named `.MMIX.sec.N'. Here, N is a number, a running count +through the mmo file, starting at 0. + + A loadable section specified as: + + .section secname,"ax" + TETRA 1,2,3,4,-1,-2009 + BYTE 80 + + and linked to address `0x4', is represented by the sequence: + + 0x98080050 - lop_spec 80 + 0x00000002 - two 32-bit words for the section name + 0x7365636e - "secn" + 0x616d6500 - "ame\0" + 0x00000033 - flags CODE, READONLY, LOAD, ALLOC + 0x00000000 - high 32 bits of section length + 0x0000001c - section length is 28 bytes; 6 * 4 + 1 + alignment to 32 bits + 0x00000000 - high 32 bits of section address + 0x00000004 - section address is 4 + 0x98010002 - 64 bits with address of following data + 0x00000000 - high 32 bits of address + 0x00000004 - low 32 bits: data starts at address 4 + 0x00000001 - 1 + 0x00000002 - 2 + 0x00000003 - 3 + 0x00000004 - 4 + 0xffffffff - -1 + 0xfffff827 - -2009 + 0x50000000 - 80 as a byte, padded with zeros. + + Note that the lop_spec wrapping does not include the section +contents. Compare this to a non-loaded section specified as: + + .section thirdsec + TETRA 200001,100002 + BYTE 38,40 + + This, when linked to address `0x200000000000001c', is represented by: + + 0x98080050 - lop_spec 80 + 0x00000002 - two 32-bit words for the section name + 0x7365636e - "thir" + 0x616d6500 - "dsec" + 0x00000010 - flag READONLY + 0x00000000 - high 32 bits of section length + 0x0000000c - section length is 12 bytes; 2 * 4 + 2 + alignment to 32 bits + 0x20000000 - high 32 bits of address + 0x0000001c - low 32 bits of address 0x200000000000001c + 0x00030d41 - 200001 + 0x000186a2 - 100002 + 0x26280000 - 38, 40 as bytes, padded with zeros + + For the latter example, the section contents must not be loaded in +memory, and is therefore specified as part of the special data. The +address is usually unimportant but might provide information for e.g. +the DWARF 2 debugging format. + + +File: bfd.info, Node: GNU Free Documentation License, Next: BFD Index, Prev: BFD back ends, Up: Top + + Version 1.3, 3 November 2008 + + Copyright (C) 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc. + `http://fsf.org/' + + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + 0. PREAMBLE + + The purpose of this License is to make a manual, textbook, or other + functional and useful document "free" in the sense of freedom: to + assure everyone the effective freedom to copy and redistribute it, + with or without modifying it, either commercially or + noncommercially. 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A copy of the license is included in the section entitled ``GNU + Free Documentation License''. + + If you have Invariant Sections, Front-Cover Texts and Back-Cover +Texts, replace the "with...Texts." line with this: + + with the Invariant Sections being LIST THEIR TITLES, with + the Front-Cover Texts being LIST, and with the Back-Cover Texts + being LIST. + + If you have Invariant Sections without Cover Texts, or some other +combination of the three, merge those two alternatives to suit the +situation. + + If your document contains nontrivial examples of program code, we +recommend releasing these examples in parallel under your choice of +free software license, such as the GNU General Public License, to +permit their use in free software. + + +File: bfd.info, Node: BFD Index, Prev: GNU Free Documentation License, Up: Top + +BFD Index +********* + + +* Menu: + +* _bfd_final_link_relocate: Relocating the section contents. + (line 22) +* _bfd_generic_link_add_archive_symbols: Adding symbols from an archive. + (line 12) +* _bfd_generic_link_add_one_symbol: Adding symbols from an object file. + (line 19) +* _bfd_generic_make_empty_symbol: symbol handling functions. + (line 92) +* _bfd_link_add_symbols in target vector: Adding Symbols to the Hash Table. + (line 6) +* _bfd_link_final_link in target vector: Performing the Final Link. + (line 6) +* _bfd_link_hash_table_create in target vector: Creating a Linker Hash Table. + (line 6) +* _bfd_relocate_contents: Relocating the section contents. + (line 22) +* aout_SIZE_machine_type: aout. (line 147) +* aout_SIZE_mkobject: aout. (line 139) +* aout_SIZE_new_section_hook: aout. (line 177) +* aout_SIZE_set_arch_mach: aout. (line 164) +* aout_SIZE_some_aout_object_p: aout. (line 125) +* aout_SIZE_swap_exec_header_in: aout. (line 101) +* aout_SIZE_swap_exec_header_out: aout. (line 113) +* arelent_chain: typedef arelent. (line 339) +* BFD: Overview. (line 6) +* BFD canonical format: Canonical format. (line 11) +* bfd_alloc: Opening and Closing. + (line 210) +* bfd_alloc2: Opening and Closing. + (line 219) +* bfd_alt_mach_code: BFD front end. (line 689) +* bfd_arch_bits_per_address: Architectures. (line 517) +* bfd_arch_bits_per_byte: Architectures. (line 509) +* bfd_arch_get_compatible: Architectures. (line 452) +* bfd_arch_list: Architectures. (line 443) +* bfd_arch_mach_octets_per_byte: Architectures. (line 586) +* BFD_ARELOC_BFIN_ADD: howto manager. (line 1005) +* BFD_ARELOC_BFIN_ADDR: howto manager. (line 1056) +* BFD_ARELOC_BFIN_AND: howto manager. (line 1026) +* BFD_ARELOC_BFIN_COMP: howto manager. (line 1047) +* BFD_ARELOC_BFIN_CONST: howto manager. (line 1002) +* BFD_ARELOC_BFIN_DIV: howto manager. (line 1014) +* BFD_ARELOC_BFIN_HWPAGE: howto manager. (line 1053) +* BFD_ARELOC_BFIN_LAND: howto manager. (line 1035) +* BFD_ARELOC_BFIN_LEN: howto manager. (line 1041) +* BFD_ARELOC_BFIN_LOR: howto manager. (line 1038) +* BFD_ARELOC_BFIN_LSHIFT: howto manager. (line 1020) +* BFD_ARELOC_BFIN_MOD: howto manager. (line 1017) +* BFD_ARELOC_BFIN_MULT: howto manager. (line 1011) +* BFD_ARELOC_BFIN_NEG: howto manager. (line 1044) +* BFD_ARELOC_BFIN_OR: howto manager. (line 1029) +* BFD_ARELOC_BFIN_PAGE: howto manager. (line 1050) +* BFD_ARELOC_BFIN_PUSH: howto manager. (line 999) +* BFD_ARELOC_BFIN_RSHIFT: howto manager. (line 1023) +* BFD_ARELOC_BFIN_SUB: howto manager. (line 1008) +* BFD_ARELOC_BFIN_XOR: howto manager. (line 1032) +* bfd_cache_close: File Caching. (line 26) +* bfd_cache_close_all: File Caching. (line 39) +* bfd_cache_init: File Caching. (line 18) +* bfd_calc_gnu_debuglink_crc32: Opening and Closing. + (line 246) +* bfd_canonicalize_reloc: BFD front end. (line 408) +* bfd_canonicalize_symtab: symbol handling functions. + (line 50) +* bfd_check_format: Formats. (line 21) +* bfd_check_format_matches: Formats. (line 52) +* bfd_check_overflow: typedef arelent. (line 351) +* bfd_close: Opening and Closing. + (line 135) +* bfd_close_all_done: Opening and Closing. + (line 153) +* bfd_coff_backend_data: coff. (line 304) +* bfd_copy_private_bfd_data: BFD front end. (line 547) +* bfd_copy_private_header_data: BFD front end. (line 529) +* bfd_copy_private_section_data: section prototypes. (line 255) +* bfd_copy_private_symbol_data: symbol handling functions. + (line 140) +* bfd_core_file_failing_command: Core Files. (line 12) +* bfd_core_file_failing_signal: Core Files. (line 21) +* bfd_create: Opening and Closing. + (line 172) +* bfd_create_gnu_debuglink_section: Opening and Closing. + (line 312) +* bfd_decode_symclass: symbol handling functions. + (line 111) +* bfd_default_arch_struct: Architectures. (line 464) +* bfd_default_compatible: Architectures. (line 526) +* bfd_default_reloc_type_lookup: howto manager. (line 2247) +* bfd_default_scan: Architectures. (line 535) +* bfd_default_set_arch_mach: Architectures. (line 482) +* bfd_demangle: BFD front end. (line 787) +* bfd_emul_get_commonpagesize: BFD front end. (line 767) +* bfd_emul_get_maxpagesize: BFD front end. (line 747) +* bfd_emul_set_commonpagesize: BFD front end. (line 778) +* bfd_emul_set_maxpagesize: BFD front end. (line 758) +* bfd_errmsg: BFD front end. (line 333) +* bfd_fdopenr: Opening and Closing. + (line 46) +* bfd_fill_in_gnu_debuglink_section: Opening and Closing. + (line 326) +* bfd_find_target: bfd_target. (line 445) +* bfd_find_version_for_sym: Writing the symbol table. + (line 80) +* bfd_follow_gnu_debuglink: Opening and Closing. + (line 291) +* bfd_fopen: Opening and Closing. + (line 9) +* bfd_format_string: Formats. (line 79) +* bfd_generic_define_common_symbol: Writing the symbol table. + (line 67) +* bfd_generic_discard_group: section prototypes. (line 281) +* bfd_generic_gc_sections: howto manager. (line 2278) +* bfd_generic_get_relocated_section_contents: howto manager. (line 2298) +* bfd_generic_is_group_section: section prototypes. (line 273) +* bfd_generic_merge_sections: howto manager. (line 2288) +* bfd_generic_relax_section: howto manager. (line 2265) +* bfd_get_arch: Architectures. (line 493) +* bfd_get_arch_info: Architectures. (line 545) +* bfd_get_arch_size: BFD front end. (line 452) +* bfd_get_error: BFD front end. (line 314) +* bfd_get_error_handler: BFD front end. (line 384) +* bfd_get_gp_size: BFD front end. (line 493) +* bfd_get_mach: Architectures. (line 501) +* bfd_get_mtime: BFD front end. (line 831) +* bfd_get_next_mapent: Archives. (line 52) +* bfd_get_reloc_code_name: howto manager. (line 2256) +* bfd_get_reloc_size: typedef arelent. (line 330) +* bfd_get_reloc_upper_bound: BFD front end. (line 398) +* bfd_get_section_by_name: section prototypes. (line 17) +* bfd_get_section_by_name_if: section prototypes. (line 31) +* bfd_get_section_contents: section prototypes. (line 228) +* bfd_get_sign_extend_vma: BFD front end. (line 465) +* bfd_get_size <1>: Internal. (line 25) +* bfd_get_size: BFD front end. (line 840) +* bfd_get_symtab_upper_bound: symbol handling functions. + (line 6) +* bfd_get_unique_section_name: section prototypes. (line 50) +* bfd_h_put_size: Internal. (line 97) +* bfd_hash_allocate: Creating and Freeing a Hash Table. + (line 17) +* bfd_hash_lookup: Looking Up or Entering a String. + (line 6) +* bfd_hash_newfunc: Creating and Freeing a Hash Table. + (line 12) +* bfd_hash_set_default_size: Creating and Freeing a Hash Table. + (line 25) +* bfd_hash_table_free: Creating and Freeing a Hash Table. + (line 21) +* bfd_hash_table_init: Creating and Freeing a Hash Table. + (line 6) +* bfd_hash_table_init_n: Creating and Freeing a Hash Table. + (line 6) +* bfd_hash_traverse: Traversing a Hash Table. + (line 6) +* bfd_init: Initialization. (line 11) +* bfd_install_relocation: typedef arelent. (line 392) +* bfd_is_local_label: symbol handling functions. + (line 17) +* bfd_is_local_label_name: symbol handling functions. + (line 26) +* bfd_is_target_special_symbol: symbol handling functions. + (line 38) +* bfd_is_undefined_symclass: symbol handling functions. + (line 120) +* bfd_link_split_section: Writing the symbol table. + (line 44) +* bfd_log2: Internal. (line 164) +* bfd_lookup_arch: Architectures. (line 553) +* bfd_make_debug_symbol: symbol handling functions. + (line 102) +* bfd_make_empty_symbol: symbol handling functions. + (line 78) +* bfd_make_readable: Opening and Closing. + (line 196) +* bfd_make_section: section prototypes. (line 129) +* bfd_make_section_anyway: section prototypes. (line 100) +* bfd_make_section_anyway_with_flags: section prototypes. (line 82) +* bfd_make_section_old_way: section prototypes. (line 62) +* bfd_make_section_with_flags: section prototypes. (line 116) +* bfd_make_writable: Opening and Closing. + (line 182) +* bfd_malloc_and_get_section: section prototypes. (line 245) +* bfd_map_over_sections: section prototypes. (line 155) +* bfd_merge_private_bfd_data: BFD front end. (line 563) +* bfd_mmap: BFD front end. (line 869) +* bfd_octets_per_byte: Architectures. (line 576) +* bfd_open_file: File Caching. (line 52) +* bfd_openr: Opening and Closing. + (line 30) +* bfd_openr_iovec: Opening and Closing. + (line 76) +* bfd_openr_next_archived_file: Archives. (line 78) +* bfd_openstreamr: Opening and Closing. + (line 67) +* bfd_openw: Opening and Closing. + (line 123) +* bfd_perform_relocation: typedef arelent. (line 367) +* bfd_perror: BFD front end. (line 342) +* bfd_preserve_finish: BFD front end. (line 737) +* bfd_preserve_restore: BFD front end. (line 727) +* bfd_preserve_save: BFD front end. (line 711) +* bfd_print_symbol_vandf: symbol handling functions. + (line 70) +* bfd_printable_arch_mach: Architectures. (line 564) +* bfd_printable_name: Architectures. (line 424) +* bfd_put_size: Internal. (line 22) +* BFD_RELOC_12_PCREL: howto manager. (line 39) +* BFD_RELOC_14: howto manager. (line 31) +* BFD_RELOC_16: howto manager. (line 30) +* BFD_RELOC_16_BASEREL: howto manager. (line 95) +* BFD_RELOC_16_GOT_PCREL: howto manager. (line 52) +* BFD_RELOC_16_GOTOFF: howto manager. (line 55) +* BFD_RELOC_16_PCREL: howto manager. (line 38) +* BFD_RELOC_16_PCREL_S2: howto manager. (line 107) +* BFD_RELOC_16_PLT_PCREL: howto manager. (line 63) +* BFD_RELOC_16_PLTOFF: howto manager. (line 67) +* BFD_RELOC_16C_ABS20: howto manager. (line 1838) +* BFD_RELOC_16C_ABS20_C: howto manager. (line 1839) +* BFD_RELOC_16C_ABS24: howto manager. (line 1840) +* BFD_RELOC_16C_ABS24_C: howto manager. (line 1841) +* BFD_RELOC_16C_DISP04: howto manager. (line 1818) +* BFD_RELOC_16C_DISP04_C: howto manager. (line 1819) +* BFD_RELOC_16C_DISP08: howto manager. (line 1820) +* BFD_RELOC_16C_DISP08_C: howto manager. (line 1821) +* BFD_RELOC_16C_DISP16: howto manager. (line 1822) +* BFD_RELOC_16C_DISP16_C: howto manager. (line 1823) +* BFD_RELOC_16C_DISP24: howto manager. (line 1824) +* BFD_RELOC_16C_DISP24_C: howto manager. (line 1825) +* BFD_RELOC_16C_DISP24a: howto manager. (line 1826) +* BFD_RELOC_16C_DISP24a_C: howto manager. (line 1827) +* BFD_RELOC_16C_IMM04: howto manager. (line 1842) +* BFD_RELOC_16C_IMM04_C: howto manager. (line 1843) +* BFD_RELOC_16C_IMM16: howto manager. (line 1844) +* BFD_RELOC_16C_IMM16_C: howto manager. (line 1845) +* BFD_RELOC_16C_IMM20: howto manager. (line 1846) +* BFD_RELOC_16C_IMM20_C: howto manager. (line 1847) +* BFD_RELOC_16C_IMM24: howto manager. (line 1848) +* BFD_RELOC_16C_IMM24_C: howto manager. (line 1849) +* BFD_RELOC_16C_IMM32: howto manager. (line 1850) +* BFD_RELOC_16C_IMM32_C: howto manager. (line 1851) +* BFD_RELOC_16C_NUM08: howto manager. (line 1812) +* BFD_RELOC_16C_NUM08_C: howto manager. (line 1813) +* BFD_RELOC_16C_NUM16: howto manager. (line 1814) +* BFD_RELOC_16C_NUM16_C: howto manager. (line 1815) +* BFD_RELOC_16C_NUM32: howto manager. (line 1816) +* BFD_RELOC_16C_NUM32_C: howto manager. (line 1817) +* BFD_RELOC_16C_REG04: howto manager. (line 1828) +* BFD_RELOC_16C_REG04_C: howto manager. (line 1829) +* BFD_RELOC_16C_REG04a: howto manager. (line 1830) +* BFD_RELOC_16C_REG04a_C: howto manager. (line 1831) +* BFD_RELOC_16C_REG14: howto manager. (line 1832) +* BFD_RELOC_16C_REG14_C: howto manager. (line 1833) +* BFD_RELOC_16C_REG16: howto manager. (line 1834) +* BFD_RELOC_16C_REG16_C: howto manager. (line 1835) +* BFD_RELOC_16C_REG20: howto manager. (line 1836) +* BFD_RELOC_16C_REG20_C: howto manager. (line 1837) +* BFD_RELOC_23_PCREL_S2: howto manager. (line 108) +* BFD_RELOC_24: howto manager. (line 29) +* BFD_RELOC_24_PCREL: howto manager. (line 37) +* BFD_RELOC_24_PLT_PCREL: howto manager. (line 62) +* BFD_RELOC_26: howto manager. (line 28) +* BFD_RELOC_32: howto manager. (line 27) +* BFD_RELOC_32_BASEREL: howto manager. (line 94) +* BFD_RELOC_32_GOT_PCREL: howto manager. (line 51) +* BFD_RELOC_32_GOTOFF: howto manager. (line 54) +* BFD_RELOC_32_PCREL: howto manager. (line 36) +* BFD_RELOC_32_PCREL_S2: howto manager. (line 106) +* BFD_RELOC_32_PLT_PCREL: howto manager. (line 61) +* BFD_RELOC_32_PLTOFF: howto manager. (line 66) +* BFD_RELOC_32_SECREL: howto manager. (line 48) +* BFD_RELOC_386_COPY: howto manager. (line 505) +* BFD_RELOC_386_GLOB_DAT: howto manager. (line 506) +* BFD_RELOC_386_GOT32: howto manager. (line 503) +* BFD_RELOC_386_GOTOFF: howto manager. (line 509) +* BFD_RELOC_386_GOTPC: howto manager. (line 510) +* BFD_RELOC_386_IRELATIVE: howto manager. (line 526) +* BFD_RELOC_386_JUMP_SLOT: howto manager. (line 507) +* BFD_RELOC_386_PLT32: howto manager. (line 504) +* BFD_RELOC_386_RELATIVE: howto manager. (line 508) +* BFD_RELOC_386_TLS_DESC: howto manager. (line 525) +* BFD_RELOC_386_TLS_DESC_CALL: howto manager. (line 524) +* BFD_RELOC_386_TLS_DTPMOD32: howto manager. (line 520) +* BFD_RELOC_386_TLS_DTPOFF32: howto manager. (line 521) +* BFD_RELOC_386_TLS_GD: howto manager. (line 515) +* BFD_RELOC_386_TLS_GOTDESC: howto manager. (line 523) +* BFD_RELOC_386_TLS_GOTIE: howto manager. (line 513) +* BFD_RELOC_386_TLS_IE: howto manager. (line 512) +* BFD_RELOC_386_TLS_IE_32: howto manager. (line 518) +* BFD_RELOC_386_TLS_LDM: howto manager. (line 516) +* BFD_RELOC_386_TLS_LDO_32: howto manager. (line 517) +* BFD_RELOC_386_TLS_LE: howto manager. (line 514) +* BFD_RELOC_386_TLS_LE_32: howto manager. (line 519) +* BFD_RELOC_386_TLS_TPOFF: howto manager. (line 511) +* BFD_RELOC_386_TLS_TPOFF32: howto manager. (line 522) +* BFD_RELOC_390_12: howto manager. (line 1498) +* BFD_RELOC_390_20: howto manager. (line 1598) +* BFD_RELOC_390_COPY: howto manager. (line 1507) +* BFD_RELOC_390_GLOB_DAT: howto manager. (line 1510) +* BFD_RELOC_390_GOT12: howto manager. (line 1501) +* BFD_RELOC_390_GOT16: howto manager. (line 1522) +* BFD_RELOC_390_GOT20: howto manager. (line 1599) +* BFD_RELOC_390_GOT64: howto manager. (line 1540) +* BFD_RELOC_390_GOTENT: howto manager. (line 1546) +* BFD_RELOC_390_GOTOFF64: howto manager. (line 1549) +* BFD_RELOC_390_GOTPC: howto manager. (line 1519) +* BFD_RELOC_390_GOTPCDBL: howto manager. (line 1537) +* BFD_RELOC_390_GOTPLT12: howto manager. (line 1552) +* BFD_RELOC_390_GOTPLT16: howto manager. (line 1555) +* BFD_RELOC_390_GOTPLT20: howto manager. (line 1600) +* BFD_RELOC_390_GOTPLT32: howto manager. (line 1558) +* BFD_RELOC_390_GOTPLT64: howto manager. (line 1561) +* BFD_RELOC_390_GOTPLTENT: howto manager. (line 1564) +* BFD_RELOC_390_JMP_SLOT: howto manager. (line 1513) +* BFD_RELOC_390_PC16DBL: howto manager. (line 1525) +* BFD_RELOC_390_PC32DBL: howto manager. (line 1531) +* BFD_RELOC_390_PLT16DBL: howto manager. (line 1528) +* BFD_RELOC_390_PLT32: howto manager. (line 1504) +* BFD_RELOC_390_PLT32DBL: howto manager. (line 1534) +* BFD_RELOC_390_PLT64: howto manager. (line 1543) +* BFD_RELOC_390_PLTOFF16: howto manager. (line 1567) +* BFD_RELOC_390_PLTOFF32: howto manager. (line 1570) +* BFD_RELOC_390_PLTOFF64: howto manager. (line 1573) +* BFD_RELOC_390_RELATIVE: howto manager. (line 1516) +* BFD_RELOC_390_TLS_DTPMOD: howto manager. (line 1593) +* BFD_RELOC_390_TLS_DTPOFF: howto manager. (line 1594) +* BFD_RELOC_390_TLS_GD32: howto manager. (line 1579) +* BFD_RELOC_390_TLS_GD64: howto manager. (line 1580) +* BFD_RELOC_390_TLS_GDCALL: howto manager. (line 1577) +* BFD_RELOC_390_TLS_GOTIE12: howto manager. (line 1581) +* BFD_RELOC_390_TLS_GOTIE20: howto manager. (line 1601) +* BFD_RELOC_390_TLS_GOTIE32: howto manager. (line 1582) +* BFD_RELOC_390_TLS_GOTIE64: howto manager. (line 1583) +* BFD_RELOC_390_TLS_IE32: howto manager. (line 1586) +* BFD_RELOC_390_TLS_IE64: howto manager. (line 1587) +* BFD_RELOC_390_TLS_IEENT: howto manager. (line 1588) +* BFD_RELOC_390_TLS_LDCALL: howto manager. (line 1578) +* BFD_RELOC_390_TLS_LDM32: howto manager. (line 1584) +* BFD_RELOC_390_TLS_LDM64: howto manager. (line 1585) +* BFD_RELOC_390_TLS_LDO32: howto manager. (line 1591) +* BFD_RELOC_390_TLS_LDO64: howto manager. (line 1592) +* BFD_RELOC_390_TLS_LE32: howto manager. (line 1589) +* BFD_RELOC_390_TLS_LE64: howto manager. (line 1590) +* BFD_RELOC_390_TLS_LOAD: howto manager. (line 1576) +* BFD_RELOC_390_TLS_TPOFF: howto manager. (line 1595) +* BFD_RELOC_64: howto manager. (line 26) +* BFD_RELOC_64_PCREL: howto manager. (line 35) +* BFD_RELOC_64_PLT_PCREL: howto manager. (line 60) +* BFD_RELOC_64_PLTOFF: howto manager. (line 65) +* BFD_RELOC_68K_GLOB_DAT: howto manager. (line 74) +* BFD_RELOC_68K_JMP_SLOT: howto manager. (line 75) +* BFD_RELOC_68K_RELATIVE: howto manager. (line 76) +* BFD_RELOC_68K_TLS_GD16: howto manager. (line 78) +* BFD_RELOC_68K_TLS_GD32: howto manager. (line 77) +* BFD_RELOC_68K_TLS_GD8: howto manager. (line 79) +* BFD_RELOC_68K_TLS_IE16: howto manager. (line 87) +* BFD_RELOC_68K_TLS_IE32: howto manager. (line 86) +* BFD_RELOC_68K_TLS_IE8: howto manager. (line 88) +* BFD_RELOC_68K_TLS_LDM16: howto manager. (line 81) +* BFD_RELOC_68K_TLS_LDM32: howto manager. (line 80) +* BFD_RELOC_68K_TLS_LDM8: howto manager. (line 82) +* BFD_RELOC_68K_TLS_LDO16: howto manager. (line 84) +* BFD_RELOC_68K_TLS_LDO32: howto manager. (line 83) +* BFD_RELOC_68K_TLS_LDO8: howto manager. (line 85) +* BFD_RELOC_68K_TLS_LE16: howto manager. (line 90) +* BFD_RELOC_68K_TLS_LE32: howto manager. (line 89) +* BFD_RELOC_68K_TLS_LE8: howto manager. (line 91) +* BFD_RELOC_8: howto manager. (line 32) +* BFD_RELOC_860_COPY: howto manager. (line 1966) +* BFD_RELOC_860_GLOB_DAT: howto manager. (line 1967) +* BFD_RELOC_860_HAGOT: howto manager. (line 1992) +* BFD_RELOC_860_HAGOTOFF: howto manager. (line 1993) +* BFD_RELOC_860_HAPC: howto manager. (line 1994) +* BFD_RELOC_860_HIGH: howto manager. (line 1995) +* BFD_RELOC_860_HIGHADJ: howto manager. (line 1991) +* BFD_RELOC_860_HIGOT: howto manager. (line 1996) +* BFD_RELOC_860_HIGOTOFF: howto manager. (line 1997) +* BFD_RELOC_860_JUMP_SLOT: howto manager. (line 1968) +* BFD_RELOC_860_LOGOT0: howto manager. (line 1980) +* BFD_RELOC_860_LOGOT1: howto manager. (line 1982) +* BFD_RELOC_860_LOGOTOFF0: howto manager. (line 1984) +* BFD_RELOC_860_LOGOTOFF1: howto manager. (line 1986) +* BFD_RELOC_860_LOGOTOFF2: howto manager. (line 1988) +* BFD_RELOC_860_LOGOTOFF3: howto manager. (line 1989) +* BFD_RELOC_860_LOPC: howto manager. (line 1990) +* BFD_RELOC_860_LOW0: howto manager. (line 1973) +* BFD_RELOC_860_LOW1: howto manager. (line 1975) +* BFD_RELOC_860_LOW2: howto manager. (line 1977) +* BFD_RELOC_860_LOW3: howto manager. (line 1979) +* BFD_RELOC_860_PC16: howto manager. (line 1972) +* BFD_RELOC_860_PC26: howto manager. (line 1970) +* BFD_RELOC_860_PLT26: howto manager. (line 1971) +* BFD_RELOC_860_RELATIVE: howto manager. (line 1969) +* BFD_RELOC_860_SPGOT0: howto manager. (line 1981) +* BFD_RELOC_860_SPGOT1: howto manager. (line 1983) +* BFD_RELOC_860_SPGOTOFF0: howto manager. (line 1985) +* BFD_RELOC_860_SPGOTOFF1: howto manager. (line 1987) +* BFD_RELOC_860_SPLIT0: howto manager. (line 1974) +* BFD_RELOC_860_SPLIT1: howto manager. (line 1976) +* BFD_RELOC_860_SPLIT2: howto manager. (line 1978) +* BFD_RELOC_8_BASEREL: howto manager. (line 99) +* BFD_RELOC_8_FFnn: howto manager. (line 103) +* BFD_RELOC_8_GOT_PCREL: howto manager. (line 53) +* BFD_RELOC_8_GOTOFF: howto manager. (line 59) +* BFD_RELOC_8_PCREL: howto manager. (line 40) +* BFD_RELOC_8_PLT_PCREL: howto manager. (line 64) +* BFD_RELOC_8_PLTOFF: howto manager. (line 71) +* BFD_RELOC_ALPHA_BOH: howto manager. (line 313) +* BFD_RELOC_ALPHA_BRSGP: howto manager. (line 296) +* BFD_RELOC_ALPHA_BSR: howto manager. (line 305) +* BFD_RELOC_ALPHA_CODEADDR: howto manager. (line 287) +* BFD_RELOC_ALPHA_DTPMOD64: howto manager. (line 319) +* BFD_RELOC_ALPHA_DTPREL16: howto manager. (line 324) +* BFD_RELOC_ALPHA_DTPREL64: howto manager. (line 321) +* BFD_RELOC_ALPHA_DTPREL_HI16: howto manager. (line 322) +* BFD_RELOC_ALPHA_DTPREL_LO16: howto manager. (line 323) +* BFD_RELOC_ALPHA_ELF_LITERAL: howto manager. (line 252) +* BFD_RELOC_ALPHA_GOTDTPREL16: howto manager. (line 320) +* BFD_RELOC_ALPHA_GOTTPREL16: howto manager. (line 325) +* BFD_RELOC_ALPHA_GPDISP: howto manager. (line 246) +* BFD_RELOC_ALPHA_GPDISP_HI16: howto manager. (line 232) +* BFD_RELOC_ALPHA_GPDISP_LO16: howto manager. (line 240) +* BFD_RELOC_ALPHA_GPREL_HI16: howto manager. (line 291) +* BFD_RELOC_ALPHA_GPREL_LO16: howto manager. (line 292) +* BFD_RELOC_ALPHA_HINT: howto manager. (line 278) +* BFD_RELOC_ALPHA_LDA: howto manager. (line 309) +* BFD_RELOC_ALPHA_LINKAGE: howto manager. (line 283) +* BFD_RELOC_ALPHA_LITERAL: howto manager. (line 251) +* BFD_RELOC_ALPHA_LITUSE: howto manager. (line 253) +* BFD_RELOC_ALPHA_NOP: howto manager. (line 301) +* BFD_RELOC_ALPHA_TLSGD: howto manager. (line 317) +* BFD_RELOC_ALPHA_TLSLDM: howto manager. (line 318) +* BFD_RELOC_ALPHA_TPREL16: howto manager. (line 329) +* BFD_RELOC_ALPHA_TPREL64: howto manager. (line 326) +* BFD_RELOC_ALPHA_TPREL_HI16: howto manager. (line 327) +* BFD_RELOC_ALPHA_TPREL_LO16: howto manager. (line 328) +* BFD_RELOC_ARC_B22_PCREL: howto manager. (line 934) +* BFD_RELOC_ARC_B26: howto manager. (line 939) +* BFD_RELOC_ARM_ADR_IMM: howto manager. (line 827) +* BFD_RELOC_ARM_ADRL_IMMEDIATE: howto manager. (line 814) +* BFD_RELOC_ARM_ALU_PC_G0: howto manager. (line 781) +* BFD_RELOC_ARM_ALU_PC_G0_NC: howto manager. (line 780) +* BFD_RELOC_ARM_ALU_PC_G1: howto manager. (line 783) +* BFD_RELOC_ARM_ALU_PC_G1_NC: howto manager. (line 782) +* BFD_RELOC_ARM_ALU_PC_G2: howto manager. (line 784) +* BFD_RELOC_ARM_ALU_SB_G0: howto manager. (line 795) +* BFD_RELOC_ARM_ALU_SB_G0_NC: howto manager. (line 794) +* BFD_RELOC_ARM_ALU_SB_G1: howto manager. (line 797) +* BFD_RELOC_ARM_ALU_SB_G1_NC: howto manager. (line 796) +* BFD_RELOC_ARM_ALU_SB_G2: howto manager. (line 798) +* BFD_RELOC_ARM_CP_OFF_IMM: howto manager. (line 823) +* BFD_RELOC_ARM_CP_OFF_IMM_S2: howto manager. (line 824) +* BFD_RELOC_ARM_GLOB_DAT: howto manager. (line 762) +* BFD_RELOC_ARM_GOT32: howto manager. (line 763) +* BFD_RELOC_ARM_GOTOFF: howto manager. (line 766) +* BFD_RELOC_ARM_GOTPC: howto manager. (line 767) +* BFD_RELOC_ARM_HWLITERAL: howto manager. (line 834) +* BFD_RELOC_ARM_IMMEDIATE: howto manager. (line 813) +* BFD_RELOC_ARM_IN_POOL: howto manager. (line 830) +* BFD_RELOC_ARM_JUMP_SLOT: howto manager. (line 761) +* BFD_RELOC_ARM_LDC_PC_G0: howto manager. (line 791) +* BFD_RELOC_ARM_LDC_PC_G1: howto manager. (line 792) +* BFD_RELOC_ARM_LDC_PC_G2: howto manager. (line 793) +* BFD_RELOC_ARM_LDC_SB_G0: howto manager. (line 805) +* BFD_RELOC_ARM_LDC_SB_G1: howto manager. (line 806) +* BFD_RELOC_ARM_LDC_SB_G2: howto manager. (line 807) +* BFD_RELOC_ARM_LDR_IMM: howto manager. (line 828) +* BFD_RELOC_ARM_LDR_PC_G0: howto manager. (line 785) +* BFD_RELOC_ARM_LDR_PC_G1: howto manager. (line 786) +* BFD_RELOC_ARM_LDR_PC_G2: howto manager. (line 787) +* BFD_RELOC_ARM_LDR_SB_G0: howto manager. (line 799) +* BFD_RELOC_ARM_LDR_SB_G1: howto manager. (line 800) +* BFD_RELOC_ARM_LDR_SB_G2: howto manager. (line 801) +* BFD_RELOC_ARM_LDRS_PC_G0: howto manager. (line 788) +* BFD_RELOC_ARM_LDRS_PC_G1: howto manager. (line 789) +* BFD_RELOC_ARM_LDRS_PC_G2: howto manager. (line 790) +* BFD_RELOC_ARM_LDRS_SB_G0: howto manager. (line 802) +* BFD_RELOC_ARM_LDRS_SB_G1: howto manager. (line 803) +* BFD_RELOC_ARM_LDRS_SB_G2: howto manager. (line 804) +* BFD_RELOC_ARM_LITERAL: howto manager. (line 829) +* BFD_RELOC_ARM_MOVT: howto manager. (line 752) +* BFD_RELOC_ARM_MOVT_PCREL: howto manager. (line 754) +* BFD_RELOC_ARM_MOVW: howto manager. (line 751) +* BFD_RELOC_ARM_MOVW_PCREL: howto manager. (line 753) +* BFD_RELOC_ARM_MULTI: howto manager. (line 822) +* BFD_RELOC_ARM_OFFSET_IMM: howto manager. (line 725) +* BFD_RELOC_ARM_OFFSET_IMM8: howto manager. (line 831) +* BFD_RELOC_ARM_PCREL_BLX: howto manager. (line 696) +* BFD_RELOC_ARM_PCREL_BRANCH: howto manager. (line 692) +* BFD_RELOC_ARM_PCREL_CALL: howto manager. (line 706) +* BFD_RELOC_ARM_PCREL_JUMP: howto manager. (line 710) +* BFD_RELOC_ARM_PLT32: howto manager. (line 764) +* BFD_RELOC_ARM_PREL31: howto manager. (line 748) +* BFD_RELOC_ARM_RELATIVE: howto manager. (line 765) +* BFD_RELOC_ARM_ROSEGREL32: howto manager. (line 737) +* BFD_RELOC_ARM_SBREL32: howto manager. (line 740) +* BFD_RELOC_ARM_SHIFT_IMM: howto manager. (line 819) +* BFD_RELOC_ARM_SMC: howto manager. (line 820) +* BFD_RELOC_ARM_SWI: howto manager. (line 821) +* BFD_RELOC_ARM_T32_ADD_IMM: howto manager. (line 816) +* BFD_RELOC_ARM_T32_ADD_PC12: howto manager. (line 818) +* BFD_RELOC_ARM_T32_CP_OFF_IMM: howto manager. (line 825) +* BFD_RELOC_ARM_T32_CP_OFF_IMM_S2: howto manager. (line 826) +* BFD_RELOC_ARM_T32_IMM12: howto manager. (line 817) +* BFD_RELOC_ARM_T32_IMMEDIATE: howto manager. (line 815) +* BFD_RELOC_ARM_T32_OFFSET_IMM: howto manager. (line 833) +* BFD_RELOC_ARM_T32_OFFSET_U8: howto manager. (line 832) +* BFD_RELOC_ARM_TARGET1: howto manager. (line 733) +* BFD_RELOC_ARM_TARGET2: howto manager. (line 743) +* BFD_RELOC_ARM_THUMB_ADD: howto manager. (line 835) +* BFD_RELOC_ARM_THUMB_IMM: howto manager. (line 836) +* BFD_RELOC_ARM_THUMB_MOVT: howto manager. (line 756) +* BFD_RELOC_ARM_THUMB_MOVT_PCREL: howto manager. (line 758) +* BFD_RELOC_ARM_THUMB_MOVW: howto manager. (line 755) +* BFD_RELOC_ARM_THUMB_MOVW_PCREL: howto manager. (line 757) +* BFD_RELOC_ARM_THUMB_OFFSET: howto manager. (line 729) +* BFD_RELOC_ARM_THUMB_SHIFT: howto manager. (line 837) +* BFD_RELOC_ARM_TLS_DTPMOD32: howto manager. (line 774) +* BFD_RELOC_ARM_TLS_DTPOFF32: howto manager. (line 773) +* BFD_RELOC_ARM_TLS_GD32: howto manager. (line 770) +* BFD_RELOC_ARM_TLS_IE32: howto manager. (line 776) +* BFD_RELOC_ARM_TLS_LDM32: howto manager. (line 772) +* BFD_RELOC_ARM_TLS_LDO32: howto manager. (line 771) +* BFD_RELOC_ARM_TLS_LE32: howto manager. (line 777) +* BFD_RELOC_ARM_TLS_TPOFF32: howto manager. (line 775) +* BFD_RELOC_ARM_V4BX: howto manager. (line 810) +* BFD_RELOC_AVR_13_PCREL: howto manager. (line 1399) +* BFD_RELOC_AVR_16_PM: howto manager. (line 1403) +* BFD_RELOC_AVR_6: howto manager. (line 1490) +* BFD_RELOC_AVR_6_ADIW: howto manager. (line 1494) +* BFD_RELOC_AVR_7_PCREL: howto manager. (line 1395) +* BFD_RELOC_AVR_CALL: howto manager. (line 1482) +* BFD_RELOC_AVR_HH8_LDI: howto manager. (line 1415) +* BFD_RELOC_AVR_HH8_LDI_NEG: howto manager. (line 1434) +* BFD_RELOC_AVR_HH8_LDI_PM: howto manager. (line 1463) +* BFD_RELOC_AVR_HH8_LDI_PM_NEG: howto manager. (line 1477) +* BFD_RELOC_AVR_HI8_LDI: howto manager. (line 1411) +* BFD_RELOC_AVR_HI8_LDI_GS: howto manager. (line 1457) +* BFD_RELOC_AVR_HI8_LDI_NEG: howto manager. (line 1429) +* BFD_RELOC_AVR_HI8_LDI_PM: howto manager. (line 1453) +* BFD_RELOC_AVR_HI8_LDI_PM_NEG: howto manager. (line 1472) +* BFD_RELOC_AVR_LDI: howto manager. (line 1486) +* BFD_RELOC_AVR_LO8_LDI: howto manager. (line 1407) +* BFD_RELOC_AVR_LO8_LDI_GS: howto manager. (line 1447) +* BFD_RELOC_AVR_LO8_LDI_NEG: howto manager. (line 1424) +* BFD_RELOC_AVR_LO8_LDI_PM: howto manager. (line 1443) +* BFD_RELOC_AVR_LO8_LDI_PM_NEG: howto manager. (line 1468) +* BFD_RELOC_AVR_MS8_LDI: howto manager. (line 1420) +* BFD_RELOC_AVR_MS8_LDI_NEG: howto manager. (line 1439) +* BFD_RELOC_BFIN_10_PCREL: howto manager. (line 959) +* BFD_RELOC_BFIN_11_PCREL: howto manager. (line 962) +* BFD_RELOC_BFIN_12_PCREL_JUMP: howto manager. (line 965) +* BFD_RELOC_BFIN_12_PCREL_JUMP_S: howto manager. (line 968) +* BFD_RELOC_BFIN_16_HIGH: howto manager. (line 947) +* BFD_RELOC_BFIN_16_IMM: howto manager. (line 944) +* BFD_RELOC_BFIN_16_LOW: howto manager. (line 956) +* BFD_RELOC_BFIN_24_PCREL_CALL_X: howto manager. (line 971) +* BFD_RELOC_BFIN_24_PCREL_JUMP_L: howto manager. (line 974) +* BFD_RELOC_BFIN_4_PCREL: howto manager. (line 950) +* BFD_RELOC_BFIN_5_PCREL: howto manager. (line 953) +* BFD_RELOC_BFIN_FUNCDESC: howto manager. (line 980) +* BFD_RELOC_BFIN_FUNCDESC_GOT17M4: howto manager. (line 981) +* BFD_RELOC_BFIN_FUNCDESC_GOTHI: howto manager. (line 982) +* BFD_RELOC_BFIN_FUNCDESC_GOTLO: howto manager. (line 983) +* BFD_RELOC_BFIN_FUNCDESC_GOTOFF17M4: howto manager. (line 985) +* BFD_RELOC_BFIN_FUNCDESC_GOTOFFHI: howto manager. (line 986) +* BFD_RELOC_BFIN_FUNCDESC_GOTOFFLO: howto manager. (line 987) +* BFD_RELOC_BFIN_FUNCDESC_VALUE: howto manager. (line 984) +* BFD_RELOC_BFIN_GOT: howto manager. (line 993) +* BFD_RELOC_BFIN_GOT17M4: howto manager. (line 977) +* BFD_RELOC_BFIN_GOTHI: howto manager. (line 978) +* BFD_RELOC_BFIN_GOTLO: howto manager. (line 979) +* BFD_RELOC_BFIN_GOTOFF17M4: howto manager. (line 988) +* BFD_RELOC_BFIN_GOTOFFHI: howto manager. (line 989) +* BFD_RELOC_BFIN_GOTOFFLO: howto manager. (line 990) +* BFD_RELOC_BFIN_PLTPC: howto manager. (line 996) +* bfd_reloc_code_type: howto manager. (line 10) +* BFD_RELOC_CR16_ABS20: howto manager. (line 1866) +* BFD_RELOC_CR16_ABS24: howto manager. (line 1867) +* BFD_RELOC_CR16_DISP16: howto manager. (line 1877) +* BFD_RELOC_CR16_DISP20: howto manager. (line 1878) +* BFD_RELOC_CR16_DISP24: howto manager. (line 1879) +* BFD_RELOC_CR16_DISP24a: howto manager. (line 1880) +* BFD_RELOC_CR16_DISP4: howto manager. (line 1875) +* BFD_RELOC_CR16_DISP8: howto manager. (line 1876) +* BFD_RELOC_CR16_GLOB_DAT: howto manager. (line 1886) +* BFD_RELOC_CR16_GOT_REGREL20: howto manager. (line 1884) +* BFD_RELOC_CR16_GOTC_REGREL20: howto manager. (line 1885) +* BFD_RELOC_CR16_IMM16: howto manager. (line 1870) +* BFD_RELOC_CR16_IMM20: howto manager. (line 1871) +* BFD_RELOC_CR16_IMM24: howto manager. (line 1872) +* BFD_RELOC_CR16_IMM32: howto manager. (line 1873) +* BFD_RELOC_CR16_IMM32a: howto manager. (line 1874) +* BFD_RELOC_CR16_IMM4: howto manager. (line 1868) +* BFD_RELOC_CR16_IMM8: howto manager. (line 1869) +* BFD_RELOC_CR16_NUM16: howto manager. (line 1855) +* BFD_RELOC_CR16_NUM32: howto manager. (line 1856) +* BFD_RELOC_CR16_NUM32a: howto manager. (line 1857) +* BFD_RELOC_CR16_NUM8: howto manager. (line 1854) +* BFD_RELOC_CR16_REGREL0: howto manager. (line 1858) +* BFD_RELOC_CR16_REGREL14: howto manager. (line 1861) +* BFD_RELOC_CR16_REGREL14a: howto manager. (line 1862) +* BFD_RELOC_CR16_REGREL16: howto manager. (line 1863) +* BFD_RELOC_CR16_REGREL20: howto manager. (line 1864) +* BFD_RELOC_CR16_REGREL20a: howto manager. (line 1865) +* BFD_RELOC_CR16_REGREL4: howto manager. (line 1859) +* BFD_RELOC_CR16_REGREL4a: howto manager. (line 1860) +* BFD_RELOC_CR16_SWITCH16: howto manager. (line 1882) +* BFD_RELOC_CR16_SWITCH32: howto manager. (line 1883) +* BFD_RELOC_CR16_SWITCH8: howto manager. (line 1881) +* BFD_RELOC_CRIS_16_DTPREL: howto manager. (line 1957) +* BFD_RELOC_CRIS_16_GOT: howto manager. (line 1933) +* BFD_RELOC_CRIS_16_GOT_GD: howto manager. (line 1953) +* BFD_RELOC_CRIS_16_GOT_TPREL: howto manager. (line 1959) +* BFD_RELOC_CRIS_16_GOTPLT: howto manager. (line 1939) +* BFD_RELOC_CRIS_16_TPREL: howto manager. (line 1961) +* BFD_RELOC_CRIS_32_DTPREL: howto manager. (line 1956) +* BFD_RELOC_CRIS_32_GD: howto manager. (line 1954) +* BFD_RELOC_CRIS_32_GOT: howto manager. (line 1930) +* BFD_RELOC_CRIS_32_GOT_GD: howto manager. (line 1952) +* BFD_RELOC_CRIS_32_GOT_TPREL: howto manager. (line 1958) +* BFD_RELOC_CRIS_32_GOTPLT: howto manager. (line 1936) +* BFD_RELOC_CRIS_32_GOTREL: howto manager. (line 1942) +* BFD_RELOC_CRIS_32_IE: howto manager. (line 1963) +* BFD_RELOC_CRIS_32_PLT_GOTREL: howto manager. (line 1945) +* BFD_RELOC_CRIS_32_PLT_PCREL: howto manager. (line 1948) +* BFD_RELOC_CRIS_32_TPREL: howto manager. (line 1960) +* BFD_RELOC_CRIS_BDISP8: howto manager. (line 1911) +* BFD_RELOC_CRIS_COPY: howto manager. (line 1924) +* BFD_RELOC_CRIS_DTP: howto manager. (line 1955) +* BFD_RELOC_CRIS_DTPMOD: howto manager. (line 1962) +* BFD_RELOC_CRIS_GLOB_DAT: howto manager. (line 1925) +* BFD_RELOC_CRIS_JUMP_SLOT: howto manager. (line 1926) +* BFD_RELOC_CRIS_LAPCQ_OFFSET: howto manager. (line 1919) +* BFD_RELOC_CRIS_RELATIVE: howto manager. (line 1927) +* BFD_RELOC_CRIS_SIGNED_16: howto manager. (line 1917) +* BFD_RELOC_CRIS_SIGNED_6: howto manager. (line 1913) +* BFD_RELOC_CRIS_SIGNED_8: howto manager. (line 1915) +* BFD_RELOC_CRIS_UNSIGNED_16: howto manager. (line 1918) +* BFD_RELOC_CRIS_UNSIGNED_4: howto manager. (line 1920) +* BFD_RELOC_CRIS_UNSIGNED_5: howto manager. (line 1912) +* BFD_RELOC_CRIS_UNSIGNED_6: howto manager. (line 1914) +* BFD_RELOC_CRIS_UNSIGNED_8: howto manager. (line 1916) +* BFD_RELOC_CRX_ABS16: howto manager. (line 1899) +* BFD_RELOC_CRX_ABS32: howto manager. (line 1900) +* BFD_RELOC_CRX_IMM16: howto manager. (line 1904) +* BFD_RELOC_CRX_IMM32: howto manager. (line 1905) +* BFD_RELOC_CRX_NUM16: howto manager. (line 1902) +* BFD_RELOC_CRX_NUM32: howto manager. (line 1903) +* BFD_RELOC_CRX_NUM8: howto manager. (line 1901) +* BFD_RELOC_CRX_REGREL12: howto manager. (line 1895) +* BFD_RELOC_CRX_REGREL22: howto manager. (line 1896) +* BFD_RELOC_CRX_REGREL28: howto manager. (line 1897) +* BFD_RELOC_CRX_REGREL32: howto manager. (line 1898) +* BFD_RELOC_CRX_REL16: howto manager. (line 1892) +* BFD_RELOC_CRX_REL24: howto manager. (line 1893) +* BFD_RELOC_CRX_REL32: howto manager. (line 1894) +* BFD_RELOC_CRX_REL4: howto manager. (line 1889) +* BFD_RELOC_CRX_REL8: howto manager. (line 1890) +* BFD_RELOC_CRX_REL8_CMP: howto manager. (line 1891) +* BFD_RELOC_CRX_SWITCH16: howto manager. (line 1907) +* BFD_RELOC_CRX_SWITCH32: howto manager. (line 1908) +* BFD_RELOC_CRX_SWITCH8: howto manager. (line 1906) +* BFD_RELOC_CTOR: howto manager. (line 686) +* BFD_RELOC_D10V_10_PCREL_L: howto manager. (line 1063) +* BFD_RELOC_D10V_10_PCREL_R: howto manager. (line 1059) +* BFD_RELOC_D10V_18: howto manager. (line 1068) +* BFD_RELOC_D10V_18_PCREL: howto manager. (line 1071) +* BFD_RELOC_D30V_15: howto manager. (line 1086) +* BFD_RELOC_D30V_15_PCREL: howto manager. (line 1090) +* BFD_RELOC_D30V_15_PCREL_R: howto manager. (line 1094) +* BFD_RELOC_D30V_21: howto manager. (line 1099) +* BFD_RELOC_D30V_21_PCREL: howto manager. (line 1103) +* BFD_RELOC_D30V_21_PCREL_R: howto manager. (line 1107) +* BFD_RELOC_D30V_32: howto manager. (line 1112) +* BFD_RELOC_D30V_32_PCREL: howto manager. (line 1115) +* BFD_RELOC_D30V_6: howto manager. (line 1074) +* BFD_RELOC_D30V_9_PCREL: howto manager. (line 1077) +* BFD_RELOC_D30V_9_PCREL_R: howto manager. (line 1081) +* BFD_RELOC_DLX_HI16_S: howto manager. (line 1118) +* BFD_RELOC_DLX_JMP26: howto manager. (line 1124) +* BFD_RELOC_DLX_LO16: howto manager. (line 1121) +* BFD_RELOC_FR30_10_IN_8: howto manager. (line 1303) +* BFD_RELOC_FR30_12_PCREL: howto manager. (line 1311) +* BFD_RELOC_FR30_20: howto manager. (line 1287) +* BFD_RELOC_FR30_48: howto manager. (line 1284) +* BFD_RELOC_FR30_6_IN_4: howto manager. (line 1291) +* BFD_RELOC_FR30_8_IN_8: howto manager. (line 1295) +* BFD_RELOC_FR30_9_IN_8: howto manager. (line 1299) +* BFD_RELOC_FR30_9_PCREL: howto manager. (line 1307) +* BFD_RELOC_FRV_FUNCDESC: howto manager. (line 438) +* BFD_RELOC_FRV_FUNCDESC_GOT12: howto manager. (line 439) +* BFD_RELOC_FRV_FUNCDESC_GOTHI: howto manager. (line 440) +* BFD_RELOC_FRV_FUNCDESC_GOTLO: howto manager. (line 441) +* BFD_RELOC_FRV_FUNCDESC_GOTOFF12: howto manager. (line 443) +* BFD_RELOC_FRV_FUNCDESC_GOTOFFHI: howto manager. (line 444) +* BFD_RELOC_FRV_FUNCDESC_GOTOFFLO: howto manager. (line 445) +* BFD_RELOC_FRV_FUNCDESC_VALUE: howto manager. (line 442) +* BFD_RELOC_FRV_GETTLSOFF: howto manager. (line 449) +* BFD_RELOC_FRV_GETTLSOFF_RELAX: howto manager. (line 462) +* BFD_RELOC_FRV_GOT12: howto manager. (line 435) +* BFD_RELOC_FRV_GOTHI: howto manager. (line 436) +* BFD_RELOC_FRV_GOTLO: howto manager. (line 437) +* BFD_RELOC_FRV_GOTOFF12: howto manager. (line 446) +* BFD_RELOC_FRV_GOTOFFHI: howto manager. (line 447) +* BFD_RELOC_FRV_GOTOFFLO: howto manager. (line 448) +* BFD_RELOC_FRV_GOTTLSDESC12: howto manager. (line 451) +* BFD_RELOC_FRV_GOTTLSDESCHI: howto manager. (line 452) +* BFD_RELOC_FRV_GOTTLSDESCLO: howto manager. (line 453) +* BFD_RELOC_FRV_GOTTLSOFF12: howto manager. (line 457) +* BFD_RELOC_FRV_GOTTLSOFFHI: howto manager. (line 458) +* BFD_RELOC_FRV_GOTTLSOFFLO: howto manager. (line 459) +* BFD_RELOC_FRV_GPREL12: howto manager. (line 430) +* BFD_RELOC_FRV_GPREL32: howto manager. (line 432) +* BFD_RELOC_FRV_GPRELHI: howto manager. (line 433) +* BFD_RELOC_FRV_GPRELLO: howto manager. (line 434) +* BFD_RELOC_FRV_GPRELU12: howto manager. (line 431) +* BFD_RELOC_FRV_HI16: howto manager. (line 429) +* BFD_RELOC_FRV_LABEL16: howto manager. (line 426) +* BFD_RELOC_FRV_LABEL24: howto manager. (line 427) +* BFD_RELOC_FRV_LO16: howto manager. (line 428) +* BFD_RELOC_FRV_TLSDESC_RELAX: howto manager. (line 461) +* BFD_RELOC_FRV_TLSDESC_VALUE: howto manager. (line 450) +* BFD_RELOC_FRV_TLSMOFF: howto manager. (line 464) +* BFD_RELOC_FRV_TLSMOFF12: howto manager. (line 454) +* BFD_RELOC_FRV_TLSMOFFHI: howto manager. (line 455) +* BFD_RELOC_FRV_TLSMOFFLO: howto manager. (line 456) +* BFD_RELOC_FRV_TLSOFF: howto manager. (line 460) +* BFD_RELOC_FRV_TLSOFF_RELAX: howto manager. (line 463) +* BFD_RELOC_GPREL16: howto manager. (line 121) +* BFD_RELOC_GPREL32: howto manager. (line 122) +* BFD_RELOC_H8_DIR16A8: howto manager. (line 2004) +* BFD_RELOC_H8_DIR16R8: howto manager. (line 2005) +* BFD_RELOC_H8_DIR24A8: howto manager. (line 2006) +* BFD_RELOC_H8_DIR24R8: howto manager. (line 2007) +* BFD_RELOC_H8_DIR32A16: howto manager. (line 2008) +* BFD_RELOC_HI16: howto manager. (line 342) +* BFD_RELOC_HI16_BASEREL: howto manager. (line 97) +* BFD_RELOC_HI16_GOTOFF: howto manager. (line 57) +* BFD_RELOC_HI16_PCREL: howto manager. (line 354) +* BFD_RELOC_HI16_PLTOFF: howto manager. (line 69) +* BFD_RELOC_HI16_S: howto manager. (line 345) +* BFD_RELOC_HI16_S_BASEREL: howto manager. (line 98) +* BFD_RELOC_HI16_S_GOTOFF: howto manager. (line 58) +* BFD_RELOC_HI16_S_PCREL: howto manager. (line 357) +* BFD_RELOC_HI16_S_PLTOFF: howto manager. (line 70) +* BFD_RELOC_HI22: howto manager. (line 116) +* BFD_RELOC_I370_D12: howto manager. (line 683) +* BFD_RELOC_I960_CALLJ: howto manager. (line 128) +* BFD_RELOC_IA64_COPY: howto manager. (line 1748) +* BFD_RELOC_IA64_DIR32LSB: howto manager. (line 1693) +* BFD_RELOC_IA64_DIR32MSB: howto manager. (line 1692) +* BFD_RELOC_IA64_DIR64LSB: howto manager. (line 1695) +* BFD_RELOC_IA64_DIR64MSB: howto manager. (line 1694) +* BFD_RELOC_IA64_DTPMOD64LSB: howto manager. (line 1758) +* BFD_RELOC_IA64_DTPMOD64MSB: howto manager. (line 1757) +* BFD_RELOC_IA64_DTPREL14: howto manager. (line 1760) +* BFD_RELOC_IA64_DTPREL22: howto manager. (line 1761) +* BFD_RELOC_IA64_DTPREL32LSB: howto manager. (line 1764) +* BFD_RELOC_IA64_DTPREL32MSB: howto manager. (line 1763) +* BFD_RELOC_IA64_DTPREL64I: howto manager. (line 1762) +* BFD_RELOC_IA64_DTPREL64LSB: howto manager. (line 1766) +* BFD_RELOC_IA64_DTPREL64MSB: howto manager. (line 1765) +* BFD_RELOC_IA64_FPTR32LSB: howto manager. (line 1710) +* BFD_RELOC_IA64_FPTR32MSB: howto manager. (line 1709) +* BFD_RELOC_IA64_FPTR64I: howto manager. (line 1708) +* BFD_RELOC_IA64_FPTR64LSB: howto manager. (line 1712) +* BFD_RELOC_IA64_FPTR64MSB: howto manager. (line 1711) +* BFD_RELOC_IA64_GPREL22: howto manager. (line 1696) +* BFD_RELOC_IA64_GPREL32LSB: howto manager. (line 1699) +* BFD_RELOC_IA64_GPREL32MSB: howto manager. (line 1698) +* BFD_RELOC_IA64_GPREL64I: howto manager. (line 1697) +* BFD_RELOC_IA64_GPREL64LSB: howto manager. (line 1701) +* BFD_RELOC_IA64_GPREL64MSB: howto manager. (line 1700) +* BFD_RELOC_IA64_IMM14: howto manager. (line 1689) +* BFD_RELOC_IA64_IMM22: howto manager. (line 1690) +* BFD_RELOC_IA64_IMM64: howto manager. (line 1691) +* BFD_RELOC_IA64_IPLTLSB: howto manager. (line 1747) +* BFD_RELOC_IA64_IPLTMSB: howto manager. (line 1746) +* BFD_RELOC_IA64_LDXMOV: howto manager. (line 1750) +* BFD_RELOC_IA64_LTOFF22: howto manager. (line 1702) +* BFD_RELOC_IA64_LTOFF22X: howto manager. (line 1749) +* BFD_RELOC_IA64_LTOFF64I: howto manager. (line 1703) +* BFD_RELOC_IA64_LTOFF_DTPMOD22: howto manager. (line 1759) +* BFD_RELOC_IA64_LTOFF_DTPREL22: howto manager. (line 1767) +* BFD_RELOC_IA64_LTOFF_FPTR22: howto manager. (line 1724) +* BFD_RELOC_IA64_LTOFF_FPTR32LSB: howto manager. (line 1727) +* BFD_RELOC_IA64_LTOFF_FPTR32MSB: howto manager. (line 1726) +* BFD_RELOC_IA64_LTOFF_FPTR64I: howto manager. (line 1725) +* BFD_RELOC_IA64_LTOFF_FPTR64LSB: howto manager. (line 1729) +* BFD_RELOC_IA64_LTOFF_FPTR64MSB: howto manager. (line 1728) +* BFD_RELOC_IA64_LTOFF_TPREL22: howto manager. (line 1756) +* BFD_RELOC_IA64_LTV32LSB: howto manager. (line 1743) +* BFD_RELOC_IA64_LTV32MSB: howto manager. (line 1742) +* BFD_RELOC_IA64_LTV64LSB: howto manager. (line 1745) +* BFD_RELOC_IA64_LTV64MSB: howto manager. (line 1744) +* BFD_RELOC_IA64_PCREL21B: howto manager. (line 1713) +* BFD_RELOC_IA64_PCREL21BI: howto manager. (line 1714) +* BFD_RELOC_IA64_PCREL21F: howto manager. (line 1716) +* BFD_RELOC_IA64_PCREL21M: howto manager. (line 1715) +* BFD_RELOC_IA64_PCREL22: howto manager. (line 1717) +* BFD_RELOC_IA64_PCREL32LSB: howto manager. (line 1721) +* BFD_RELOC_IA64_PCREL32MSB: howto manager. (line 1720) +* BFD_RELOC_IA64_PCREL60B: howto manager. (line 1718) +* BFD_RELOC_IA64_PCREL64I: howto manager. (line 1719) +* BFD_RELOC_IA64_PCREL64LSB: howto manager. (line 1723) +* BFD_RELOC_IA64_PCREL64MSB: howto manager. (line 1722) +* BFD_RELOC_IA64_PLTOFF22: howto manager. (line 1704) +* BFD_RELOC_IA64_PLTOFF64I: howto manager. (line 1705) +* BFD_RELOC_IA64_PLTOFF64LSB: howto manager. (line 1707) +* BFD_RELOC_IA64_PLTOFF64MSB: howto manager. (line 1706) +* BFD_RELOC_IA64_REL32LSB: howto manager. (line 1739) +* BFD_RELOC_IA64_REL32MSB: howto manager. (line 1738) +* BFD_RELOC_IA64_REL64LSB: howto manager. (line 1741) +* BFD_RELOC_IA64_REL64MSB: howto manager. (line 1740) +* BFD_RELOC_IA64_SECREL32LSB: howto manager. (line 1735) +* BFD_RELOC_IA64_SECREL32MSB: howto manager. (line 1734) +* BFD_RELOC_IA64_SECREL64LSB: howto manager. (line 1737) +* BFD_RELOC_IA64_SECREL64MSB: howto manager. (line 1736) +* BFD_RELOC_IA64_SEGREL32LSB: howto manager. (line 1731) +* BFD_RELOC_IA64_SEGREL32MSB: howto manager. (line 1730) +* BFD_RELOC_IA64_SEGREL64LSB: howto manager. (line 1733) +* BFD_RELOC_IA64_SEGREL64MSB: howto manager. (line 1732) +* BFD_RELOC_IA64_TPREL14: howto manager. (line 1751) +* BFD_RELOC_IA64_TPREL22: howto manager. (line 1752) +* BFD_RELOC_IA64_TPREL64I: howto manager. (line 1753) +* BFD_RELOC_IA64_TPREL64LSB: howto manager. (line 1755) +* BFD_RELOC_IA64_TPREL64MSB: howto manager. (line 1754) +* BFD_RELOC_IP2K_ADDR16CJP: howto manager. (line 1641) +* BFD_RELOC_IP2K_BANK: howto manager. (line 1638) +* BFD_RELOC_IP2K_EX8DATA: howto manager. (line 1649) +* BFD_RELOC_IP2K_FR9: howto manager. (line 1635) +* BFD_RELOC_IP2K_FR_OFFSET: howto manager. (line 1662) +* BFD_RELOC_IP2K_HI8DATA: howto manager. (line 1648) +* BFD_RELOC_IP2K_HI8INSN: howto manager. (line 1653) +* BFD_RELOC_IP2K_LO8DATA: howto manager. (line 1647) +* BFD_RELOC_IP2K_LO8INSN: howto manager. (line 1652) +* BFD_RELOC_IP2K_PAGE3: howto manager. (line 1644) +* BFD_RELOC_IP2K_PC_SKIP: howto manager. (line 1656) +* BFD_RELOC_IP2K_TEXT: howto manager. (line 1659) +* BFD_RELOC_IQ2000_OFFSET_16: howto manager. (line 2058) +* BFD_RELOC_IQ2000_OFFSET_21: howto manager. (line 2059) +* BFD_RELOC_IQ2000_UHI16: howto manager. (line 2060) +* BFD_RELOC_LM32_16_GOT: howto manager. (line 2165) +* BFD_RELOC_LM32_BRANCH: howto manager. (line 2164) +* BFD_RELOC_LM32_CALL: howto manager. (line 2163) +* BFD_RELOC_LM32_COPY: howto manager. (line 2168) +* BFD_RELOC_LM32_GLOB_DAT: howto manager. (line 2169) +* BFD_RELOC_LM32_GOTOFF_HI16: howto manager. (line 2166) +* BFD_RELOC_LM32_GOTOFF_LO16: howto manager. (line 2167) +* BFD_RELOC_LM32_JMP_SLOT: howto manager. (line 2170) +* BFD_RELOC_LM32_RELATIVE: howto manager. (line 2171) +* BFD_RELOC_LO10: howto manager. (line 117) +* BFD_RELOC_LO16: howto manager. (line 351) +* BFD_RELOC_LO16_BASEREL: howto manager. (line 96) +* BFD_RELOC_LO16_GOTOFF: howto manager. (line 56) +* BFD_RELOC_LO16_PCREL: howto manager. (line 360) +* BFD_RELOC_LO16_PLTOFF: howto manager. (line 68) +* BFD_RELOC_M32C_HI8: howto manager. (line 1127) +* BFD_RELOC_M32C_RL_1ADDR: howto manager. (line 1129) +* BFD_RELOC_M32C_RL_2ADDR: howto manager. (line 1130) +* BFD_RELOC_M32C_RL_JUMP: howto manager. (line 1128) +* BFD_RELOC_M32R_10_PCREL: howto manager. (line 1137) +* BFD_RELOC_M32R_18_PCREL: howto manager. (line 1141) +* BFD_RELOC_M32R_24: howto manager. (line 1133) +* BFD_RELOC_M32R_26_PCREL: howto manager. (line 1144) +* BFD_RELOC_M32R_26_PLTREL: howto manager. (line 1163) +* BFD_RELOC_M32R_COPY: howto manager. (line 1164) +* BFD_RELOC_M32R_GLOB_DAT: howto manager. (line 1165) +* BFD_RELOC_M32R_GOT16_HI_SLO: howto manager. (line 1174) +* BFD_RELOC_M32R_GOT16_HI_ULO: howto manager. (line 1173) +* BFD_RELOC_M32R_GOT16_LO: howto manager. (line 1175) +* BFD_RELOC_M32R_GOT24: howto manager. (line 1162) +* BFD_RELOC_M32R_GOTOFF: howto manager. (line 1168) +* BFD_RELOC_M32R_GOTOFF_HI_SLO: howto manager. (line 1170) +* BFD_RELOC_M32R_GOTOFF_HI_ULO: howto manager. (line 1169) +* BFD_RELOC_M32R_GOTOFF_LO: howto manager. (line 1171) +* BFD_RELOC_M32R_GOTPC24: howto manager. (line 1172) +* BFD_RELOC_M32R_GOTPC_HI_SLO: howto manager. (line 1177) +* BFD_RELOC_M32R_GOTPC_HI_ULO: howto manager. (line 1176) +* BFD_RELOC_M32R_GOTPC_LO: howto manager. (line 1178) +* BFD_RELOC_M32R_HI16_SLO: howto manager. (line 1151) +* BFD_RELOC_M32R_HI16_ULO: howto manager. (line 1147) +* BFD_RELOC_M32R_JMP_SLOT: howto manager. (line 1166) +* BFD_RELOC_M32R_LO16: howto manager. (line 1155) +* BFD_RELOC_M32R_RELATIVE: howto manager. (line 1167) +* BFD_RELOC_M32R_SDA16: howto manager. (line 1158) +* BFD_RELOC_M68HC11_24: howto manager. (line 1803) +* BFD_RELOC_M68HC11_3B: howto manager. (line 1778) +* BFD_RELOC_M68HC11_HI8: howto manager. (line 1770) +* BFD_RELOC_M68HC11_LO16: howto manager. (line 1792) +* BFD_RELOC_M68HC11_LO8: howto manager. (line 1774) +* BFD_RELOC_M68HC11_PAGE: howto manager. (line 1798) +* BFD_RELOC_M68HC11_RL_GROUP: howto manager. (line 1787) +* BFD_RELOC_M68HC11_RL_JUMP: howto manager. (line 1781) +* BFD_RELOC_M68HC12_5B: howto manager. (line 1809) +* BFD_RELOC_MACH_O_PAIR: howto manager. (line 2178) +* BFD_RELOC_MACH_O_SECTDIFF: howto manager. (line 2174) +* BFD_RELOC_MCORE_PCREL_32: howto manager. (line 1318) +* BFD_RELOC_MCORE_PCREL_IMM11BY2: howto manager. (line 1316) +* BFD_RELOC_MCORE_PCREL_IMM4BY2: howto manager. (line 1317) +* BFD_RELOC_MCORE_PCREL_IMM8BY4: howto manager. (line 1315) +* BFD_RELOC_MCORE_PCREL_JSR_IMM11BY2: howto manager. (line 1319) +* BFD_RELOC_MCORE_RVA: howto manager. (line 1320) +* BFD_RELOC_MEP_16: howto manager. (line 1324) +* BFD_RELOC_MEP_32: howto manager. (line 1325) +* BFD_RELOC_MEP_8: howto manager. (line 1323) +* BFD_RELOC_MEP_ADDR24A4: howto manager. (line 1340) +* BFD_RELOC_MEP_GNU_VTENTRY: howto manager. (line 1342) +* BFD_RELOC_MEP_GNU_VTINHERIT: howto manager. (line 1341) +* BFD_RELOC_MEP_GPREL: howto manager. (line 1334) +* BFD_RELOC_MEP_HI16S: howto manager. (line 1333) +* BFD_RELOC_MEP_HI16U: howto manager. (line 1332) +* BFD_RELOC_MEP_LOW16: howto manager. (line 1331) +* BFD_RELOC_MEP_PCABS24A2: howto manager. (line 1330) +* BFD_RELOC_MEP_PCREL12A2: howto manager. (line 1327) +* BFD_RELOC_MEP_PCREL17A2: howto manager. (line 1328) +* BFD_RELOC_MEP_PCREL24A2: howto manager. (line 1329) +* BFD_RELOC_MEP_PCREL8A2: howto manager. (line 1326) +* BFD_RELOC_MEP_TPREL: howto manager. (line 1335) +* BFD_RELOC_MEP_TPREL7: howto manager. (line 1336) +* BFD_RELOC_MEP_TPREL7A2: howto manager. (line 1337) +* BFD_RELOC_MEP_TPREL7A4: howto manager. (line 1338) +* BFD_RELOC_MEP_UIMM24: howto manager. (line 1339) +* BFD_RELOC_MICROBLAZE_32_GOTOFF: howto manager. (line 2225) +* BFD_RELOC_MICROBLAZE_32_LO: howto manager. (line 2181) +* BFD_RELOC_MICROBLAZE_32_LO_PCREL: howto manager. (line 2185) +* BFD_RELOC_MICROBLAZE_32_ROSDA: howto manager. (line 2189) +* BFD_RELOC_MICROBLAZE_32_RWSDA: howto manager. (line 2193) +* BFD_RELOC_MICROBLAZE_32_SYM_OP_SYM: howto manager. (line 2197) +* BFD_RELOC_MICROBLAZE_64_GOT: howto manager. (line 2211) +* BFD_RELOC_MICROBLAZE_64_GOTOFF: howto manager. (line 2220) +* BFD_RELOC_MICROBLAZE_64_GOTPC: howto manager. (line 2206) +* BFD_RELOC_MICROBLAZE_64_NONE: howto manager. (line 2201) +* BFD_RELOC_MICROBLAZE_64_PLT: howto manager. (line 2215) +* BFD_RELOC_MICROBLAZE_COPY: howto manager. (line 2229) +* BFD_RELOC_MIPS16_CALL16: howto manager. (line 364) +* BFD_RELOC_MIPS16_GOT16: howto manager. (line 363) +* BFD_RELOC_MIPS16_GPREL: howto manager. (line 339) +* BFD_RELOC_MIPS16_HI16: howto manager. (line 368) +* BFD_RELOC_MIPS16_HI16_S: howto manager. (line 371) +* BFD_RELOC_MIPS16_JMP: howto manager. (line 336) +* BFD_RELOC_MIPS16_LO16: howto manager. (line 377) +* BFD_RELOC_MIPS_CALL16: howto manager. (line 384) +* BFD_RELOC_MIPS_CALL_HI16: howto manager. (line 387) +* BFD_RELOC_MIPS_CALL_LO16: howto manager. (line 388) +* BFD_RELOC_MIPS_COPY: howto manager. (line 419) +* BFD_RELOC_MIPS_DELETE: howto manager. (line 397) +* BFD_RELOC_MIPS_GOT16: howto manager. (line 383) +* BFD_RELOC_MIPS_GOT_DISP: howto manager. (line 392) +* BFD_RELOC_MIPS_GOT_HI16: howto manager. (line 385) +* BFD_RELOC_MIPS_GOT_LO16: howto manager. (line 386) +* BFD_RELOC_MIPS_GOT_OFST: howto manager. (line 391) +* BFD_RELOC_MIPS_GOT_PAGE: howto manager. (line 390) +* BFD_RELOC_MIPS_HIGHER: howto manager. (line 399) +* BFD_RELOC_MIPS_HIGHEST: howto manager. (line 398) +* BFD_RELOC_MIPS_INSERT_A: howto manager. (line 395) +* BFD_RELOC_MIPS_INSERT_B: howto manager. (line 396) +* BFD_RELOC_MIPS_JALR: howto manager. (line 403) +* BFD_RELOC_MIPS_JMP: howto manager. (line 332) +* BFD_RELOC_MIPS_JUMP_SLOT: howto manager. (line 420) +* BFD_RELOC_MIPS_LITERAL: howto manager. (line 380) +* BFD_RELOC_MIPS_REL16: howto manager. (line 401) +* BFD_RELOC_MIPS_RELGOT: howto manager. (line 402) +* BFD_RELOC_MIPS_SCN_DISP: howto manager. (line 400) +* BFD_RELOC_MIPS_SHIFT5: howto manager. (line 393) +* BFD_RELOC_MIPS_SHIFT6: howto manager. (line 394) +* BFD_RELOC_MIPS_SUB: howto manager. (line 389) +* BFD_RELOC_MIPS_TLS_DTPMOD32: howto manager. (line 404) +* BFD_RELOC_MIPS_TLS_DTPMOD64: howto manager. (line 406) +* BFD_RELOC_MIPS_TLS_DTPREL32: howto manager. (line 405) +* BFD_RELOC_MIPS_TLS_DTPREL64: howto manager. (line 407) +* BFD_RELOC_MIPS_TLS_DTPREL_HI16: howto manager. (line 410) +* BFD_RELOC_MIPS_TLS_DTPREL_LO16: howto manager. (line 411) +* BFD_RELOC_MIPS_TLS_GD: howto manager. (line 408) +* BFD_RELOC_MIPS_TLS_GOTTPREL: howto manager. (line 412) +* BFD_RELOC_MIPS_TLS_LDM: howto manager. (line 409) +* BFD_RELOC_MIPS_TLS_TPREL32: howto manager. (line 413) +* BFD_RELOC_MIPS_TLS_TPREL64: howto manager. (line 414) +* BFD_RELOC_MIPS_TLS_TPREL_HI16: howto manager. (line 415) +* BFD_RELOC_MIPS_TLS_TPREL_LO16: howto manager. (line 416) +* BFD_RELOC_MMIX_ADDR19: howto manager. (line 1371) +* BFD_RELOC_MMIX_ADDR27: howto manager. (line 1375) +* BFD_RELOC_MMIX_BASE_PLUS_OFFSET: howto manager. (line 1387) +* BFD_RELOC_MMIX_CBRANCH: howto manager. (line 1351) +* BFD_RELOC_MMIX_CBRANCH_1: howto manager. (line 1353) +* BFD_RELOC_MMIX_CBRANCH_2: howto manager. (line 1354) +* BFD_RELOC_MMIX_CBRANCH_3: howto manager. (line 1355) +* BFD_RELOC_MMIX_CBRANCH_J: howto manager. (line 1352) +* BFD_RELOC_MMIX_GETA: howto manager. (line 1345) +* BFD_RELOC_MMIX_GETA_1: howto manager. (line 1346) +* BFD_RELOC_MMIX_GETA_2: howto manager. (line 1347) +* BFD_RELOC_MMIX_GETA_3: howto manager. (line 1348) +* BFD_RELOC_MMIX_JMP: howto manager. (line 1365) +* BFD_RELOC_MMIX_JMP_1: howto manager. (line 1366) +* BFD_RELOC_MMIX_JMP_2: howto manager. (line 1367) +* BFD_RELOC_MMIX_JMP_3: howto manager. (line 1368) +* BFD_RELOC_MMIX_LOCAL: howto manager. (line 1391) +* BFD_RELOC_MMIX_PUSHJ: howto manager. (line 1358) +* BFD_RELOC_MMIX_PUSHJ_1: howto manager. (line 1359) +* BFD_RELOC_MMIX_PUSHJ_2: howto manager. (line 1360) +* BFD_RELOC_MMIX_PUSHJ_3: howto manager. (line 1361) +* BFD_RELOC_MMIX_PUSHJ_STUBBABLE: howto manager. (line 1362) +* BFD_RELOC_MMIX_REG: howto manager. (line 1383) +* BFD_RELOC_MMIX_REG_OR_BYTE: howto manager. (line 1379) +* BFD_RELOC_MN10300_16_PCREL: howto manager. (line 1253) +* BFD_RELOC_MN10300_32_PCREL: howto manager. (line 1249) +* BFD_RELOC_MN10300_ALIGN: howto manager. (line 499) +* BFD_RELOC_MN10300_COPY: howto manager. (line 482) +* BFD_RELOC_MN10300_GLOB_DAT: howto manager. (line 485) +* BFD_RELOC_MN10300_GOT16: howto manager. (line 478) +* BFD_RELOC_MN10300_GOT24: howto manager. (line 474) +* BFD_RELOC_MN10300_GOT32: howto manager. (line 470) +* BFD_RELOC_MN10300_GOTOFF24: howto manager. (line 467) +* BFD_RELOC_MN10300_JMP_SLOT: howto manager. (line 488) +* BFD_RELOC_MN10300_RELATIVE: howto manager. (line 491) +* BFD_RELOC_MN10300_SYM_DIFF: howto manager. (line 494) +* BFD_RELOC_MOXIE_10_PCREL: howto manager. (line 423) +* BFD_RELOC_MSP430_10_PCREL: howto manager. (line 2049) +* BFD_RELOC_MSP430_16: howto manager. (line 2051) +* BFD_RELOC_MSP430_16_BYTE: howto manager. (line 2053) +* BFD_RELOC_MSP430_16_PCREL: howto manager. (line 2050) +* BFD_RELOC_MSP430_16_PCREL_BYTE: howto manager. (line 2052) +* BFD_RELOC_MSP430_2X_PCREL: howto manager. (line 2054) +* BFD_RELOC_MSP430_RL_PCREL: howto manager. (line 2055) +* BFD_RELOC_MT_GNU_VTENTRY: howto manager. (line 2043) +* BFD_RELOC_MT_GNU_VTINHERIT: howto manager. (line 2040) +* BFD_RELOC_MT_HI16: howto manager. (line 2034) +* BFD_RELOC_MT_LO16: howto manager. (line 2037) +* BFD_RELOC_MT_PC16: howto manager. (line 2031) +* BFD_RELOC_MT_PCINSN8: howto manager. (line 2046) +* BFD_RELOC_NONE: howto manager. (line 131) +* BFD_RELOC_NS32K_DISP_16: howto manager. (line 565) +* BFD_RELOC_NS32K_DISP_16_PCREL: howto manager. (line 568) +* BFD_RELOC_NS32K_DISP_32: howto manager. (line 566) +* BFD_RELOC_NS32K_DISP_32_PCREL: howto manager. (line 569) +* BFD_RELOC_NS32K_DISP_8: howto manager. (line 564) +* BFD_RELOC_NS32K_DISP_8_PCREL: howto manager. (line 567) +* BFD_RELOC_NS32K_IMM_16: howto manager. (line 559) +* BFD_RELOC_NS32K_IMM_16_PCREL: howto manager. (line 562) +* BFD_RELOC_NS32K_IMM_32: howto manager. (line 560) +* BFD_RELOC_NS32K_IMM_32_PCREL: howto manager. (line 563) +* BFD_RELOC_NS32K_IMM_8: howto manager. (line 558) +* BFD_RELOC_NS32K_IMM_8_PCREL: howto manager. (line 561) +* BFD_RELOC_OPENRISC_ABS_26: howto manager. (line 2000) +* BFD_RELOC_OPENRISC_REL_26: howto manager. (line 2001) +* BFD_RELOC_PDP11_DISP_6_PCREL: howto manager. (line 573) +* BFD_RELOC_PDP11_DISP_8_PCREL: howto manager. (line 572) +* BFD_RELOC_PJ_CODE_DIR16: howto manager. (line 578) +* BFD_RELOC_PJ_CODE_DIR32: howto manager. (line 579) +* BFD_RELOC_PJ_CODE_HI16: howto manager. (line 576) +* BFD_RELOC_PJ_CODE_LO16: howto manager. (line 577) +* BFD_RELOC_PJ_CODE_REL16: howto manager. (line 580) +* BFD_RELOC_PJ_CODE_REL32: howto manager. (line 581) +* BFD_RELOC_PPC64_ADDR16_DS: howto manager. (line 626) +* BFD_RELOC_PPC64_ADDR16_LO_DS: howto manager. (line 627) +* BFD_RELOC_PPC64_DTPREL16_DS: howto manager. (line 675) +* BFD_RELOC_PPC64_DTPREL16_HIGHER: howto manager. (line 677) +* BFD_RELOC_PPC64_DTPREL16_HIGHERA: howto manager. (line 678) +* BFD_RELOC_PPC64_DTPREL16_HIGHEST: howto manager. (line 679) +* BFD_RELOC_PPC64_DTPREL16_HIGHESTA: howto manager. (line 680) +* BFD_RELOC_PPC64_DTPREL16_LO_DS: howto manager. (line 676) +* BFD_RELOC_PPC64_GOT16_DS: howto manager. (line 628) +* BFD_RELOC_PPC64_GOT16_LO_DS: howto manager. (line 629) +* BFD_RELOC_PPC64_HIGHER: howto manager. (line 614) +* BFD_RELOC_PPC64_HIGHER_S: howto manager. (line 615) +* BFD_RELOC_PPC64_HIGHEST: howto manager. (line 616) +* BFD_RELOC_PPC64_HIGHEST_S: howto manager. (line 617) +* BFD_RELOC_PPC64_PLT16_LO_DS: howto manager. (line 630) +* BFD_RELOC_PPC64_PLTGOT16: howto manager. (line 622) +* BFD_RELOC_PPC64_PLTGOT16_DS: howto manager. (line 635) +* BFD_RELOC_PPC64_PLTGOT16_HA: howto manager. (line 625) +* BFD_RELOC_PPC64_PLTGOT16_HI: howto manager. (line 624) +* BFD_RELOC_PPC64_PLTGOT16_LO: howto manager. (line 623) +* BFD_RELOC_PPC64_PLTGOT16_LO_DS: howto manager. (line 636) +* BFD_RELOC_PPC64_SECTOFF_DS: howto manager. (line 631) +* BFD_RELOC_PPC64_SECTOFF_LO_DS: howto manager. (line 632) +* BFD_RELOC_PPC64_TOC: howto manager. (line 621) +* BFD_RELOC_PPC64_TOC16_DS: howto manager. (line 633) +* BFD_RELOC_PPC64_TOC16_HA: howto manager. (line 620) +* BFD_RELOC_PPC64_TOC16_HI: howto manager. (line 619) +* BFD_RELOC_PPC64_TOC16_LO: howto manager. (line 618) +* BFD_RELOC_PPC64_TOC16_LO_DS: howto manager. (line 634) +* BFD_RELOC_PPC64_TPREL16_DS: howto manager. (line 669) +* BFD_RELOC_PPC64_TPREL16_HIGHER: howto manager. (line 671) +* BFD_RELOC_PPC64_TPREL16_HIGHERA: howto manager. (line 672) +* BFD_RELOC_PPC64_TPREL16_HIGHEST: howto manager. (line 673) +* BFD_RELOC_PPC64_TPREL16_HIGHESTA: howto manager. (line 674) +* BFD_RELOC_PPC64_TPREL16_LO_DS: howto manager. (line 670) +* BFD_RELOC_PPC_B16: howto manager. (line 587) +* BFD_RELOC_PPC_B16_BRNTAKEN: howto manager. (line 589) +* BFD_RELOC_PPC_B16_BRTAKEN: howto manager. (line 588) +* BFD_RELOC_PPC_B26: howto manager. (line 584) +* BFD_RELOC_PPC_BA16: howto manager. (line 590) +* BFD_RELOC_PPC_BA16_BRNTAKEN: howto manager. (line 592) +* BFD_RELOC_PPC_BA16_BRTAKEN: howto manager. (line 591) +* BFD_RELOC_PPC_BA26: howto manager. (line 585) +* BFD_RELOC_PPC_COPY: howto manager. (line 593) +* BFD_RELOC_PPC_DTPMOD: howto manager. (line 642) +* BFD_RELOC_PPC_DTPREL: howto manager. (line 652) +* BFD_RELOC_PPC_DTPREL16: howto manager. (line 648) +* BFD_RELOC_PPC_DTPREL16_HA: howto manager. (line 651) +* BFD_RELOC_PPC_DTPREL16_HI: howto manager. (line 650) +* BFD_RELOC_PPC_DTPREL16_LO: howto manager. (line 649) +* BFD_RELOC_PPC_EMB_BIT_FLD: howto manager. (line 612) +* BFD_RELOC_PPC_EMB_MRKREF: howto manager. (line 607) +* BFD_RELOC_PPC_EMB_NADDR16: howto manager. (line 599) +* BFD_RELOC_PPC_EMB_NADDR16_HA: howto manager. (line 602) +* BFD_RELOC_PPC_EMB_NADDR16_HI: howto manager. (line 601) +* BFD_RELOC_PPC_EMB_NADDR16_LO: howto manager. (line 600) +* BFD_RELOC_PPC_EMB_NADDR32: howto manager. (line 598) +* BFD_RELOC_PPC_EMB_RELSDA: howto manager. (line 613) +* BFD_RELOC_PPC_EMB_RELSEC16: howto manager. (line 608) +* BFD_RELOC_PPC_EMB_RELST_HA: howto manager. (line 611) +* BFD_RELOC_PPC_EMB_RELST_HI: howto manager. (line 610) +* BFD_RELOC_PPC_EMB_RELST_LO: howto manager. (line 609) +* BFD_RELOC_PPC_EMB_SDA21: howto manager. (line 606) +* BFD_RELOC_PPC_EMB_SDA2I16: howto manager. (line 604) +* BFD_RELOC_PPC_EMB_SDA2REL: howto manager. (line 605) +* BFD_RELOC_PPC_EMB_SDAI16: howto manager. (line 603) +* BFD_RELOC_PPC_GLOB_DAT: howto manager. (line 594) +* BFD_RELOC_PPC_GOT_DTPREL16: howto manager. (line 665) +* BFD_RELOC_PPC_GOT_DTPREL16_HA: howto manager. (line 668) +* BFD_RELOC_PPC_GOT_DTPREL16_HI: howto manager. (line 667) +* BFD_RELOC_PPC_GOT_DTPREL16_LO: howto manager. (line 666) +* BFD_RELOC_PPC_GOT_TLSGD16: howto manager. (line 653) +* BFD_RELOC_PPC_GOT_TLSGD16_HA: howto manager. (line 656) +* BFD_RELOC_PPC_GOT_TLSGD16_HI: howto manager. (line 655) +* BFD_RELOC_PPC_GOT_TLSGD16_LO: howto manager. (line 654) +* BFD_RELOC_PPC_GOT_TLSLD16: howto manager. (line 657) +* BFD_RELOC_PPC_GOT_TLSLD16_HA: howto manager. (line 660) +* BFD_RELOC_PPC_GOT_TLSLD16_HI: howto manager. (line 659) +* BFD_RELOC_PPC_GOT_TLSLD16_LO: howto manager. (line 658) +* BFD_RELOC_PPC_GOT_TPREL16: howto manager. (line 661) +* BFD_RELOC_PPC_GOT_TPREL16_HA: howto manager. (line 664) +* BFD_RELOC_PPC_GOT_TPREL16_HI: howto manager. (line 663) +* BFD_RELOC_PPC_GOT_TPREL16_LO: howto manager. (line 662) +* BFD_RELOC_PPC_JMP_SLOT: howto manager. (line 595) +* BFD_RELOC_PPC_LOCAL24PC: howto manager. (line 597) +* BFD_RELOC_PPC_RELATIVE: howto manager. (line 596) +* BFD_RELOC_PPC_TLS: howto manager. (line 639) +* BFD_RELOC_PPC_TLSGD: howto manager. (line 640) +* BFD_RELOC_PPC_TLSLD: howto manager. (line 641) +* BFD_RELOC_PPC_TOC16: howto manager. (line 586) +* BFD_RELOC_PPC_TPREL: howto manager. (line 647) +* BFD_RELOC_PPC_TPREL16: howto manager. (line 643) +* BFD_RELOC_PPC_TPREL16_HA: howto manager. (line 646) +* BFD_RELOC_PPC_TPREL16_HI: howto manager. (line 645) +* BFD_RELOC_PPC_TPREL16_LO: howto manager. (line 644) +* BFD_RELOC_RELC: howto manager. (line 2017) +* BFD_RELOC_RVA: howto manager. (line 100) +* BFD_RELOC_SCORE16_BRANCH: howto manager. (line 1623) +* BFD_RELOC_SCORE16_JMP: howto manager. (line 1620) +* BFD_RELOC_SCORE_BCMP: howto manager. (line 1626) +* BFD_RELOC_SCORE_BRANCH: howto manager. (line 1611) +* BFD_RELOC_SCORE_CALL15: howto manager. (line 1631) +* BFD_RELOC_SCORE_DUMMY2: howto manager. (line 1607) +* BFD_RELOC_SCORE_DUMMY_HI16: howto manager. (line 1632) +* BFD_RELOC_SCORE_GOT15: howto manager. (line 1629) +* BFD_RELOC_SCORE_GOT_LO16: howto manager. (line 1630) +* BFD_RELOC_SCORE_GPREL15: howto manager. (line 1604) +* BFD_RELOC_SCORE_IMM30: howto manager. (line 1614) +* BFD_RELOC_SCORE_IMM32: howto manager. (line 1617) +* BFD_RELOC_SCORE_JMP: howto manager. (line 1608) +* BFD_RELOC_SH_ALIGN: howto manager. (line 863) +* BFD_RELOC_SH_CODE: howto manager. (line 864) +* BFD_RELOC_SH_COPY: howto manager. (line 869) +* BFD_RELOC_SH_COPY64: howto manager. (line 894) +* BFD_RELOC_SH_COUNT: howto manager. (line 862) +* BFD_RELOC_SH_DATA: howto manager. (line 865) +* BFD_RELOC_SH_DISP12: howto manager. (line 845) +* BFD_RELOC_SH_DISP12BY2: howto manager. (line 846) +* BFD_RELOC_SH_DISP12BY4: howto manager. (line 847) +* BFD_RELOC_SH_DISP12BY8: howto manager. (line 848) +* BFD_RELOC_SH_DISP20: howto manager. (line 849) +* BFD_RELOC_SH_DISP20BY8: howto manager. (line 850) +* BFD_RELOC_SH_GLOB_DAT: howto manager. (line 870) +* BFD_RELOC_SH_GLOB_DAT64: howto manager. (line 895) +* BFD_RELOC_SH_GOT10BY4: howto manager. (line 898) +* BFD_RELOC_SH_GOT10BY8: howto manager. (line 899) +* BFD_RELOC_SH_GOT_HI16: howto manager. (line 877) +* BFD_RELOC_SH_GOT_LOW16: howto manager. (line 874) +* BFD_RELOC_SH_GOT_MEDHI16: howto manager. (line 876) +* BFD_RELOC_SH_GOT_MEDLOW16: howto manager. (line 875) +* BFD_RELOC_SH_GOTOFF_HI16: howto manager. (line 889) +* BFD_RELOC_SH_GOTOFF_LOW16: howto manager. (line 886) +* BFD_RELOC_SH_GOTOFF_MEDHI16: howto manager. (line 888) +* BFD_RELOC_SH_GOTOFF_MEDLOW16: howto manager. (line 887) +* BFD_RELOC_SH_GOTPC: howto manager. (line 873) +* BFD_RELOC_SH_GOTPC_HI16: howto manager. (line 893) +* BFD_RELOC_SH_GOTPC_LOW16: howto manager. (line 890) +* BFD_RELOC_SH_GOTPC_MEDHI16: howto manager. (line 892) +* BFD_RELOC_SH_GOTPC_MEDLOW16: howto manager. (line 891) +* BFD_RELOC_SH_GOTPLT10BY4: howto manager. (line 900) +* BFD_RELOC_SH_GOTPLT10BY8: howto manager. (line 901) +* BFD_RELOC_SH_GOTPLT32: howto manager. (line 902) +* BFD_RELOC_SH_GOTPLT_HI16: howto manager. (line 881) +* BFD_RELOC_SH_GOTPLT_LOW16: howto manager. (line 878) +* BFD_RELOC_SH_GOTPLT_MEDHI16: howto manager. (line 880) +* BFD_RELOC_SH_GOTPLT_MEDLOW16: howto manager. (line 879) +* BFD_RELOC_SH_IMM3: howto manager. (line 843) +* BFD_RELOC_SH_IMM3U: howto manager. (line 844) +* BFD_RELOC_SH_IMM4: howto manager. (line 851) +* BFD_RELOC_SH_IMM4BY2: howto manager. (line 852) +* BFD_RELOC_SH_IMM4BY4: howto manager. (line 853) +* BFD_RELOC_SH_IMM8: howto manager. (line 854) +* BFD_RELOC_SH_IMM8BY2: howto manager. (line 855) +* BFD_RELOC_SH_IMM8BY4: howto manager. (line 856) +* BFD_RELOC_SH_IMM_HI16: howto manager. (line 920) +* BFD_RELOC_SH_IMM_HI16_PCREL: howto manager. (line 921) +* BFD_RELOC_SH_IMM_LOW16: howto manager. (line 914) +* BFD_RELOC_SH_IMM_LOW16_PCREL: howto manager. (line 915) +* BFD_RELOC_SH_IMM_MEDHI16: howto manager. (line 918) +* BFD_RELOC_SH_IMM_MEDHI16_PCREL: howto manager. (line 919) +* BFD_RELOC_SH_IMM_MEDLOW16: howto manager. (line 916) +* BFD_RELOC_SH_IMM_MEDLOW16_PCREL: howto manager. (line 917) +* BFD_RELOC_SH_IMMS10: howto manager. (line 908) +* BFD_RELOC_SH_IMMS10BY2: howto manager. (line 909) +* BFD_RELOC_SH_IMMS10BY4: howto manager. (line 910) +* BFD_RELOC_SH_IMMS10BY8: howto manager. (line 911) +* BFD_RELOC_SH_IMMS16: howto manager. (line 912) +* BFD_RELOC_SH_IMMS6: howto manager. (line 905) +* BFD_RELOC_SH_IMMS6BY32: howto manager. (line 906) +* BFD_RELOC_SH_IMMU16: howto manager. (line 913) +* BFD_RELOC_SH_IMMU5: howto manager. (line 904) +* BFD_RELOC_SH_IMMU6: howto manager. (line 907) +* BFD_RELOC_SH_JMP_SLOT: howto manager. (line 871) +* BFD_RELOC_SH_JMP_SLOT64: howto manager. (line 896) +* BFD_RELOC_SH_LABEL: howto manager. (line 866) +* BFD_RELOC_SH_LOOP_END: howto manager. (line 868) +* BFD_RELOC_SH_LOOP_START: howto manager. (line 867) +* BFD_RELOC_SH_PCDISP12BY2: howto manager. (line 842) +* BFD_RELOC_SH_PCDISP8BY2: howto manager. (line 841) +* BFD_RELOC_SH_PCRELIMM8BY2: howto manager. (line 857) +* BFD_RELOC_SH_PCRELIMM8BY4: howto manager. (line 858) +* BFD_RELOC_SH_PLT_HI16: howto manager. (line 885) +* BFD_RELOC_SH_PLT_LOW16: howto manager. (line 882) +* BFD_RELOC_SH_PLT_MEDHI16: howto manager. (line 884) +* BFD_RELOC_SH_PLT_MEDLOW16: howto manager. (line 883) +* BFD_RELOC_SH_PT_16: howto manager. (line 922) +* BFD_RELOC_SH_RELATIVE: howto manager. (line 872) +* BFD_RELOC_SH_RELATIVE64: howto manager. (line 897) +* BFD_RELOC_SH_SHMEDIA_CODE: howto manager. (line 903) +* BFD_RELOC_SH_SWITCH16: howto manager. (line 859) +* BFD_RELOC_SH_SWITCH32: howto manager. (line 860) +* BFD_RELOC_SH_TLS_DTPMOD32: howto manager. (line 928) +* BFD_RELOC_SH_TLS_DTPOFF32: howto manager. (line 929) +* BFD_RELOC_SH_TLS_GD_32: howto manager. (line 923) +* BFD_RELOC_SH_TLS_IE_32: howto manager. (line 926) +* BFD_RELOC_SH_TLS_LD_32: howto manager. (line 924) +* BFD_RELOC_SH_TLS_LDO_32: howto manager. (line 925) +* BFD_RELOC_SH_TLS_LE_32: howto manager. (line 927) +* BFD_RELOC_SH_TLS_TPOFF32: howto manager. (line 930) +* BFD_RELOC_SH_USES: howto manager. (line 861) +* BFD_RELOC_SPARC13: howto manager. (line 134) +* BFD_RELOC_SPARC22: howto manager. (line 133) +* BFD_RELOC_SPARC_10: howto manager. (line 161) +* BFD_RELOC_SPARC_11: howto manager. (line 162) +* BFD_RELOC_SPARC_5: howto manager. (line 174) +* BFD_RELOC_SPARC_6: howto manager. (line 173) +* BFD_RELOC_SPARC_64: howto manager. (line 160) +* BFD_RELOC_SPARC_7: howto manager. (line 172) +* BFD_RELOC_SPARC_BASE13: howto manager. (line 156) +* BFD_RELOC_SPARC_BASE22: howto manager. (line 157) +* BFD_RELOC_SPARC_COPY: howto manager. (line 141) +* BFD_RELOC_SPARC_DISP64: howto manager. (line 175) +* BFD_RELOC_SPARC_GLOB_DAT: howto manager. (line 142) +* BFD_RELOC_SPARC_GOT10: howto manager. (line 135) +* BFD_RELOC_SPARC_GOT13: howto manager. (line 136) +* BFD_RELOC_SPARC_GOT22: howto manager. (line 137) +* BFD_RELOC_SPARC_GOTDATA_HIX22: howto manager. (line 148) +* BFD_RELOC_SPARC_GOTDATA_LOX10: howto manager. (line 149) +* BFD_RELOC_SPARC_GOTDATA_OP: howto manager. (line 152) +* BFD_RELOC_SPARC_GOTDATA_OP_HIX22: howto manager. (line 150) +* BFD_RELOC_SPARC_GOTDATA_OP_LOX10: howto manager. (line 151) +* BFD_RELOC_SPARC_H44: howto manager. (line 180) +* BFD_RELOC_SPARC_HH22: howto manager. (line 164) +* BFD_RELOC_SPARC_HIX22: howto manager. (line 178) +* BFD_RELOC_SPARC_HM10: howto manager. (line 165) +* BFD_RELOC_SPARC_JMP_SLOT: howto manager. (line 143) +* BFD_RELOC_SPARC_L44: howto manager. (line 182) +* BFD_RELOC_SPARC_LM22: howto manager. (line 166) +* BFD_RELOC_SPARC_LOX10: howto manager. (line 179) +* BFD_RELOC_SPARC_M44: howto manager. (line 181) +* BFD_RELOC_SPARC_OLO10: howto manager. (line 163) +* BFD_RELOC_SPARC_PC10: howto manager. (line 138) +* BFD_RELOC_SPARC_PC22: howto manager. (line 139) +* BFD_RELOC_SPARC_PC_HH22: howto manager. (line 167) +* BFD_RELOC_SPARC_PC_HM10: howto manager. (line 168) +* BFD_RELOC_SPARC_PC_LM22: howto manager. (line 169) +* BFD_RELOC_SPARC_PLT32: howto manager. (line 176) +* BFD_RELOC_SPARC_PLT64: howto manager. (line 177) +* BFD_RELOC_SPARC_REGISTER: howto manager. (line 183) +* BFD_RELOC_SPARC_RELATIVE: howto manager. (line 144) +* BFD_RELOC_SPARC_REV32: howto manager. (line 186) +* BFD_RELOC_SPARC_TLS_DTPMOD32: howto manager. (line 207) +* BFD_RELOC_SPARC_TLS_DTPMOD64: howto manager. (line 208) +* BFD_RELOC_SPARC_TLS_DTPOFF32: howto manager. (line 209) +* BFD_RELOC_SPARC_TLS_DTPOFF64: howto manager. (line 210) +* BFD_RELOC_SPARC_TLS_GD_ADD: howto manager. (line 191) +* BFD_RELOC_SPARC_TLS_GD_CALL: howto manager. (line 192) +* BFD_RELOC_SPARC_TLS_GD_HI22: howto manager. (line 189) +* BFD_RELOC_SPARC_TLS_GD_LO10: howto manager. (line 190) +* BFD_RELOC_SPARC_TLS_IE_ADD: howto manager. (line 204) +* BFD_RELOC_SPARC_TLS_IE_HI22: howto manager. (line 200) +* BFD_RELOC_SPARC_TLS_IE_LD: howto manager. (line 202) +* BFD_RELOC_SPARC_TLS_IE_LDX: howto manager. (line 203) +* BFD_RELOC_SPARC_TLS_IE_LO10: howto manager. (line 201) +* BFD_RELOC_SPARC_TLS_LDM_ADD: howto manager. (line 195) +* BFD_RELOC_SPARC_TLS_LDM_CALL: howto manager. (line 196) +* BFD_RELOC_SPARC_TLS_LDM_HI22: howto manager. (line 193) +* BFD_RELOC_SPARC_TLS_LDM_LO10: howto manager. (line 194) +* BFD_RELOC_SPARC_TLS_LDO_ADD: howto manager. (line 199) +* BFD_RELOC_SPARC_TLS_LDO_HIX22: howto manager. (line 197) +* BFD_RELOC_SPARC_TLS_LDO_LOX10: howto manager. (line 198) +* BFD_RELOC_SPARC_TLS_LE_HIX22: howto manager. (line 205) +* BFD_RELOC_SPARC_TLS_LE_LOX10: howto manager. (line 206) +* BFD_RELOC_SPARC_TLS_TPOFF32: howto manager. (line 211) +* BFD_RELOC_SPARC_TLS_TPOFF64: howto manager. (line 212) +* BFD_RELOC_SPARC_UA16: howto manager. (line 145) +* BFD_RELOC_SPARC_UA32: howto manager. (line 146) +* BFD_RELOC_SPARC_UA64: howto manager. (line 147) +* BFD_RELOC_SPARC_WDISP16: howto manager. (line 170) +* BFD_RELOC_SPARC_WDISP19: howto manager. (line 171) +* BFD_RELOC_SPARC_WDISP22: howto manager. (line 132) +* BFD_RELOC_SPARC_WPLT30: howto manager. (line 140) +* BFD_RELOC_SPU_ADD_PIC: howto manager. (line 229) +* BFD_RELOC_SPU_HI16: howto manager. (line 226) +* BFD_RELOC_SPU_IMM10: howto manager. (line 217) +* BFD_RELOC_SPU_IMM10W: howto manager. (line 218) +* BFD_RELOC_SPU_IMM16: howto manager. (line 219) +* BFD_RELOC_SPU_IMM16W: howto manager. (line 220) +* BFD_RELOC_SPU_IMM18: howto manager. (line 221) +* BFD_RELOC_SPU_IMM7: howto manager. (line 215) +* BFD_RELOC_SPU_IMM8: howto manager. (line 216) +* BFD_RELOC_SPU_LO16: howto manager. (line 225) +* BFD_RELOC_SPU_PCREL16: howto manager. (line 224) +* BFD_RELOC_SPU_PCREL9a: howto manager. (line 222) +* BFD_RELOC_SPU_PCREL9b: howto manager. (line 223) +* BFD_RELOC_SPU_PPU32: howto manager. (line 227) +* BFD_RELOC_SPU_PPU64: howto manager. (line 228) +* BFD_RELOC_THUMB_PCREL_BLX: howto manager. (line 701) +* BFD_RELOC_THUMB_PCREL_BRANCH12: howto manager. (line 715) +* BFD_RELOC_THUMB_PCREL_BRANCH20: howto manager. (line 716) +* BFD_RELOC_THUMB_PCREL_BRANCH23: howto manager. (line 717) +* BFD_RELOC_THUMB_PCREL_BRANCH25: howto manager. (line 718) +* BFD_RELOC_THUMB_PCREL_BRANCH7: howto manager. (line 713) +* BFD_RELOC_THUMB_PCREL_BRANCH9: howto manager. (line 714) +* BFD_RELOC_TIC30_LDP: howto manager. (line 1257) +* BFD_RELOC_TIC54X_16_OF_23: howto manager. (line 1275) +* BFD_RELOC_TIC54X_23: howto manager. (line 1272) +* BFD_RELOC_TIC54X_MS7_OF_23: howto manager. (line 1280) +* BFD_RELOC_TIC54X_PARTLS7: howto manager. (line 1262) +* BFD_RELOC_TIC54X_PARTMS9: howto manager. (line 1267) +* bfd_reloc_type_lookup: howto manager. (line 2234) +* BFD_RELOC_V850_22_PCREL: howto manager. (line 1184) +* BFD_RELOC_V850_9_PCREL: howto manager. (line 1181) +* BFD_RELOC_V850_ALIGN: howto manager. (line 1242) +* BFD_RELOC_V850_CALLT_16_16_OFFSET: howto manager. (line 1233) +* BFD_RELOC_V850_CALLT_6_7_OFFSET: howto manager. (line 1230) +* BFD_RELOC_V850_LO16_SPLIT_OFFSET: howto manager. (line 1245) +* BFD_RELOC_V850_LONGCALL: howto manager. (line 1236) +* BFD_RELOC_V850_LONGJUMP: howto manager. (line 1239) +* BFD_RELOC_V850_SDA_15_16_OFFSET: howto manager. (line 1190) +* BFD_RELOC_V850_SDA_16_16_OFFSET: howto manager. (line 1187) +* BFD_RELOC_V850_SDA_16_16_SPLIT_OFFSET: howto manager. (line 1222) +* BFD_RELOC_V850_TDA_16_16_OFFSET: howto manager. (line 1212) +* BFD_RELOC_V850_TDA_4_4_OFFSET: howto manager. (line 1219) +* BFD_RELOC_V850_TDA_4_5_OFFSET: howto manager. (line 1215) +* BFD_RELOC_V850_TDA_6_8_OFFSET: howto manager. (line 1201) +* BFD_RELOC_V850_TDA_7_7_OFFSET: howto manager. (line 1209) +* BFD_RELOC_V850_TDA_7_8_OFFSET: howto manager. (line 1205) +* BFD_RELOC_V850_ZDA_15_16_OFFSET: howto manager. (line 1197) +* BFD_RELOC_V850_ZDA_16_16_OFFSET: howto manager. (line 1194) +* BFD_RELOC_V850_ZDA_16_16_SPLIT_OFFSET: howto manager. (line 1226) +* BFD_RELOC_VAX_GLOB_DAT: howto manager. (line 2026) +* BFD_RELOC_VAX_JMP_SLOT: howto manager. (line 2027) +* BFD_RELOC_VAX_RELATIVE: howto manager. (line 2028) +* BFD_RELOC_VPE4KMATH_DATA: howto manager. (line 1665) +* BFD_RELOC_VPE4KMATH_INSN: howto manager. (line 1666) +* BFD_RELOC_VTABLE_ENTRY: howto manager. (line 1670) +* BFD_RELOC_VTABLE_INHERIT: howto manager. (line 1669) +* BFD_RELOC_X86_64_32S: howto manager. (line 536) +* BFD_RELOC_X86_64_COPY: howto manager. (line 531) +* BFD_RELOC_X86_64_DTPMOD64: howto manager. (line 537) +* BFD_RELOC_X86_64_DTPOFF32: howto manager. (line 542) +* BFD_RELOC_X86_64_DTPOFF64: howto manager. (line 538) +* BFD_RELOC_X86_64_GLOB_DAT: howto manager. (line 532) +* BFD_RELOC_X86_64_GOT32: howto manager. (line 529) +* BFD_RELOC_X86_64_GOT64: howto manager. (line 547) +* BFD_RELOC_X86_64_GOTOFF64: howto manager. (line 545) +* BFD_RELOC_X86_64_GOTPC32: howto manager. (line 546) +* BFD_RELOC_X86_64_GOTPC32_TLSDESC: howto manager. (line 552) +* BFD_RELOC_X86_64_GOTPC64: howto manager. (line 549) +* BFD_RELOC_X86_64_GOTPCREL: howto manager. (line 535) +* BFD_RELOC_X86_64_GOTPCREL64: howto manager. (line 548) +* BFD_RELOC_X86_64_GOTPLT64: howto manager. (line 550) +* BFD_RELOC_X86_64_GOTTPOFF: howto manager. (line 543) +* BFD_RELOC_X86_64_IRELATIVE: howto manager. (line 555) +* BFD_RELOC_X86_64_JUMP_SLOT: howto manager. (line 533) +* BFD_RELOC_X86_64_PLT32: howto manager. (line 530) +* BFD_RELOC_X86_64_PLTOFF64: howto manager. (line 551) +* BFD_RELOC_X86_64_RELATIVE: howto manager. (line 534) +* BFD_RELOC_X86_64_TLSDESC: howto manager. (line 554) +* BFD_RELOC_X86_64_TLSDESC_CALL: howto manager. (line 553) +* BFD_RELOC_X86_64_TLSGD: howto manager. (line 540) +* BFD_RELOC_X86_64_TLSLD: howto manager. (line 541) +* BFD_RELOC_X86_64_TPOFF32: howto manager. (line 544) +* BFD_RELOC_X86_64_TPOFF64: howto manager. (line 539) +* BFD_RELOC_XC16X_PAG: howto manager. (line 2020) +* BFD_RELOC_XC16X_POF: howto manager. (line 2021) +* BFD_RELOC_XC16X_SEG: howto manager. (line 2022) +* BFD_RELOC_XC16X_SOF: howto manager. (line 2023) +* BFD_RELOC_XSTORMY16_12: howto manager. (line 2012) +* BFD_RELOC_XSTORMY16_24: howto manager. (line 2013) +* BFD_RELOC_XSTORMY16_FPTR16: howto manager. (line 2014) +* BFD_RELOC_XSTORMY16_REL_12: howto manager. (line 2011) +* BFD_RELOC_XTENSA_ASM_EXPAND: howto manager. (line 2132) +* BFD_RELOC_XTENSA_ASM_SIMPLIFY: howto manager. (line 2137) +* BFD_RELOC_XTENSA_DIFF16: howto manager. (line 2079) +* BFD_RELOC_XTENSA_DIFF32: howto manager. (line 2080) +* BFD_RELOC_XTENSA_DIFF8: howto manager. (line 2078) +* BFD_RELOC_XTENSA_GLOB_DAT: howto manager. (line 2068) +* BFD_RELOC_XTENSA_JMP_SLOT: howto manager. (line 2069) +* BFD_RELOC_XTENSA_OP0: howto manager. (line 2126) +* BFD_RELOC_XTENSA_OP1: howto manager. (line 2127) +* BFD_RELOC_XTENSA_OP2: howto manager. (line 2128) +* BFD_RELOC_XTENSA_PLT: howto manager. (line 2073) +* BFD_RELOC_XTENSA_RELATIVE: howto manager. (line 2070) +* BFD_RELOC_XTENSA_RTLD: howto manager. (line 2063) +* BFD_RELOC_XTENSA_SLOT0_ALT: howto manager. (line 2108) +* BFD_RELOC_XTENSA_SLOT0_OP: howto manager. (line 2088) +* BFD_RELOC_XTENSA_SLOT10_ALT: howto manager. (line 2118) +* BFD_RELOC_XTENSA_SLOT10_OP: howto manager. (line 2098) +* BFD_RELOC_XTENSA_SLOT11_ALT: howto manager. (line 2119) +* BFD_RELOC_XTENSA_SLOT11_OP: howto manager. (line 2099) +* BFD_RELOC_XTENSA_SLOT12_ALT: howto manager. (line 2120) +* BFD_RELOC_XTENSA_SLOT12_OP: howto manager. (line 2100) +* BFD_RELOC_XTENSA_SLOT13_ALT: howto manager. (line 2121) +* BFD_RELOC_XTENSA_SLOT13_OP: howto manager. (line 2101) +* BFD_RELOC_XTENSA_SLOT14_ALT: howto manager. (line 2122) +* BFD_RELOC_XTENSA_SLOT14_OP: howto manager. (line 2102) +* BFD_RELOC_XTENSA_SLOT1_ALT: howto manager. (line 2109) +* BFD_RELOC_XTENSA_SLOT1_OP: howto manager. (line 2089) +* BFD_RELOC_XTENSA_SLOT2_ALT: howto manager. (line 2110) +* BFD_RELOC_XTENSA_SLOT2_OP: howto manager. (line 2090) +* BFD_RELOC_XTENSA_SLOT3_ALT: howto manager. (line 2111) +* BFD_RELOC_XTENSA_SLOT3_OP: howto manager. (line 2091) +* BFD_RELOC_XTENSA_SLOT4_ALT: howto manager. (line 2112) +* BFD_RELOC_XTENSA_SLOT4_OP: howto manager. (line 2092) +* BFD_RELOC_XTENSA_SLOT5_ALT: howto manager. (line 2113) +* BFD_RELOC_XTENSA_SLOT5_OP: howto manager. (line 2093) +* BFD_RELOC_XTENSA_SLOT6_ALT: howto manager. (line 2114) +* BFD_RELOC_XTENSA_SLOT6_OP: howto manager. (line 2094) +* BFD_RELOC_XTENSA_SLOT7_ALT: howto manager. (line 2115) +* BFD_RELOC_XTENSA_SLOT7_OP: howto manager. (line 2095) +* BFD_RELOC_XTENSA_SLOT8_ALT: howto manager. (line 2116) +* BFD_RELOC_XTENSA_SLOT8_OP: howto manager. (line 2096) +* BFD_RELOC_XTENSA_SLOT9_ALT: howto manager. (line 2117) +* BFD_RELOC_XTENSA_SLOT9_OP: howto manager. (line 2097) +* BFD_RELOC_XTENSA_TLS_ARG: howto manager. (line 2147) +* BFD_RELOC_XTENSA_TLS_CALL: howto manager. (line 2148) +* BFD_RELOC_XTENSA_TLS_DTPOFF: howto manager. (line 2144) +* BFD_RELOC_XTENSA_TLS_FUNC: howto manager. (line 2146) +* BFD_RELOC_XTENSA_TLS_TPOFF: howto manager. (line 2145) +* BFD_RELOC_XTENSA_TLSDESC_ARG: howto manager. (line 2143) +* BFD_RELOC_XTENSA_TLSDESC_FN: howto manager. (line 2142) +* BFD_RELOC_Z80_DISP8: howto manager. (line 2151) +* BFD_RELOC_Z8K_CALLR: howto manager. (line 2157) +* BFD_RELOC_Z8K_DISP7: howto manager. (line 2154) +* BFD_RELOC_Z8K_IMM4L: howto manager. (line 2160) +* bfd_scan_arch: Architectures. (line 433) +* bfd_scan_vma: BFD front end. (line 513) +* bfd_seach_for_target: bfd_target. (line 470) +* bfd_section_already_linked: Writing the symbol table. + (line 55) +* bfd_section_list_clear: section prototypes. (line 8) +* bfd_sections_find_if: section prototypes. (line 176) +* bfd_set_arch_info: Architectures. (line 474) +* bfd_set_archive_head: Archives. (line 69) +* bfd_set_default_target: bfd_target. (line 435) +* bfd_set_error: BFD front end. (line 323) +* bfd_set_error_handler: BFD front end. (line 365) +* bfd_set_error_program_name: BFD front end. (line 374) +* bfd_set_file_flags: BFD front end. (line 433) +* bfd_set_format: Formats. (line 68) +* bfd_set_gp_size: BFD front end. (line 503) +* bfd_set_private_flags: BFD front end. (line 580) +* bfd_set_reloc: BFD front end. (line 423) +* bfd_set_section_contents: section prototypes. (line 207) +* bfd_set_section_flags: section prototypes. (line 140) +* bfd_set_section_size: section prototypes. (line 193) +* bfd_set_start_address: BFD front end. (line 482) +* bfd_set_symtab: symbol handling functions. + (line 60) +* bfd_symbol_info: symbol handling functions. + (line 130) +* bfd_target_list: bfd_target. (line 461) +* bfd_write_bigendian_4byte_int: Internal. (line 13) +* bfd_zalloc: Opening and Closing. + (line 228) +* bfd_zalloc2: Opening and Closing. + (line 237) +* coff_symbol_type: coff. (line 244) +* core_file_matches_executable_p: Core Files. (line 30) +* find_separate_debug_file: Opening and Closing. + (line 279) +* generic_core_file_matches_executable_p: Core Files. (line 40) +* get_debug_link_info: Opening and Closing. + (line 260) +* Hash tables: Hash Tables. (line 6) +* internal object-file format: Canonical format. (line 11) +* Linker: Linker Functions. (line 6) +* Other functions: BFD front end. (line 595) +* separate_debug_file_exists: Opening and Closing. + (line 270) +* struct bfd_iovec: BFD front end. (line 798) +* target vector (_bfd_final_link): Performing the Final Link. + (line 6) +* target vector (_bfd_link_add_symbols): Adding Symbols to the Hash Table. + (line 6) +* target vector (_bfd_link_hash_table_create): Creating a Linker Hash Table. + (line 6) +* The HOWTO Macro: typedef arelent. (line 291) +* what is it?: Overview. (line 6) + + + +Tag Table: +Node: Top1051 +Node: Overview1390 +Node: History2441 +Node: How It Works3387 +Node: What BFD Version 2 Can Do4930 +Node: BFD information loss6245 +Node: Canonical format8777 +Node: BFD front end13149 +Node: Memory Usage44457 +Node: Initialization45685 +Node: Sections46144 +Node: Section Input46627 +Node: Section Output47992 +Node: typedef asection50478 +Node: section prototypes75809 +Node: Symbols85489 +Node: Reading Symbols87084 +Node: Writing Symbols88191 +Node: Mini Symbols89900 +Node: typedef asymbol90874 +Node: symbol handling functions96933 +Node: Archives102275 +Node: Formats106001 +Node: Relocations108949 +Node: typedef arelent109676 +Node: howto manager125487 +Node: Core Files197788 +Node: Targets199605 +Node: bfd_target201575 +Node: Architectures222154 +Node: Opening and Closing245337 +Node: Internal256601 +Node: File Caching262934 +Node: Linker Functions264848 +Node: Creating a Linker Hash Table266521 +Node: Adding Symbols to the Hash Table268259 +Node: Differing file formats269159 +Node: Adding symbols from an object file270884 +Node: Adding symbols from an archive273035 +Node: Performing the Final Link275449 +Node: Information provided by the linker276691 +Node: Relocating the section contents277845 +Node: Writing the symbol table279596 +Node: Hash Tables283611 +Node: Creating and Freeing a Hash Table284809 +Node: Looking Up or Entering a String286059 +Node: Traversing a Hash Table287312 +Node: Deriving a New Hash Table Type288101 +Node: Define the Derived Structures289167 +Node: Write the Derived Creation Routine290248 +Node: Write Other Derived Routines292872 +Node: BFD back ends294187 +Node: What to Put Where294457 +Node: aout294637 +Node: coff300955 +Node: elf329388 +Node: mmo329789 +Node: File layout330717 +Node: Symbol-table336364 +Node: mmo section mapping340133 +Node: GNU Free Documentation License343785 +Node: BFD Index368868 + +End Tag Table diff --git a/uclibc-crosstools-gcc-4.4.2-1/usr/share/info/binutils.info b/uclibc-crosstools-gcc-4.4.2-1/usr/share/info/binutils.info new file mode 100644 index 0000000..bc00022 --- /dev/null +++ b/uclibc-crosstools-gcc-4.4.2-1/usr/share/info/binutils.info @@ -0,0 +1,4493 @@ +This is binutils.info, produced by makeinfo version 4.8 from +binutils.texi. + + Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, +2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 Free +Software Foundation, Inc. + + Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation; with no +Invariant Sections, with no Front-Cover Texts, and with no Back-Cover +Texts. A copy of the license is included in the section entitled "GNU +Free Documentation License". + +INFO-DIR-SECTION Software development +START-INFO-DIR-ENTRY +* Binutils: (binutils). The GNU binary utilities. +END-INFO-DIR-ENTRY + +INFO-DIR-SECTION Individual utilities +START-INFO-DIR-ENTRY +* addr2line: (binutils)addr2line. Convert addresses to file and line. +* ar: (binutils)ar. Create, modify, and extract from archives. +* c++filt: (binutils)c++filt. Filter to demangle encoded C++ symbols. +* cxxfilt: (binutils)c++filt. MS-DOS name for c++filt. +* dlltool: (binutils)dlltool. Create files needed to build and use DLLs. +* nlmconv: (binutils)nlmconv. Converts object code into an NLM. +* nm: (binutils)nm. List symbols from object files. +* objcopy: (binutils)objcopy. Copy and translate object files. +* objdump: (binutils)objdump. Display information from object files. +* ranlib: (binutils)ranlib. Generate index to archive contents. +* readelf: (binutils)readelf. Display the contents of ELF format files. +* size: (binutils)size. List section sizes and total size. +* strings: (binutils)strings. List printable strings from files. +* strip: (binutils)strip. Discard symbols. +* windmc: (binutils)windmc. Generator for Windows message resources. +* windres: (binutils)windres. Manipulate Windows resources. +END-INFO-DIR-ENTRY + + +File: binutils.info, Node: Top, Next: ar, Up: (dir) + +Introduction +************ + +This brief manual contains documentation for the GNU binary utilities +(GNU Binutils) version 2.20: + + This document is distributed under the terms of the GNU Free +Documentation License version 1.3. A copy of the license is included +in the section entitled "GNU Free Documentation License". + +* Menu: + +* ar:: Create, modify, and extract from archives +* nm:: List symbols from object files +* objcopy:: Copy and translate object files +* objdump:: Display information from object files +* ranlib:: Generate index to archive contents +* readelf:: Display the contents of ELF format files +* size:: List section sizes and total size +* strings:: List printable strings from files +* strip:: Discard symbols +* c++filt:: Filter to demangle encoded C++ symbols +* cxxfilt: c++filt. MS-DOS name for c++filt +* addr2line:: Convert addresses to file and line +* nlmconv:: Converts object code into an NLM +* windres:: Manipulate Windows resources +* windmc:: Generator for Windows message resources +* dlltool:: Create files needed to build and use DLLs +* Common Options:: Command-line options for all utilities +* Selecting the Target System:: How these utilities determine the target +* Reporting Bugs:: Reporting Bugs +* GNU Free Documentation License:: GNU Free Documentation License +* Binutils Index:: Binutils Index + + +File: binutils.info, Node: ar, Next: nm, Prev: Top, Up: Top + +1 ar +**** + + ar [`--plugin' NAME] [-]P[MOD [RELPOS] [COUNT]] ARCHIVE [MEMBER...] + ar -M [ <mri-script ] + + The GNU `ar' program creates, modifies, and extracts from archives. +An "archive" is a single file holding a collection of other files in a +structure that makes it possible to retrieve the original individual +files (called "members" of the archive). + + The original files' contents, mode (permissions), timestamp, owner, +and group are preserved in the archive, and can be restored on +extraction. + + GNU `ar' can maintain archives whose members have names of any +length; however, depending on how `ar' is configured on your system, a +limit on member-name length may be imposed for compatibility with +archive formats maintained with other tools. If it exists, the limit +is often 15 characters (typical of formats related to a.out) or 16 +characters (typical of formats related to coff). + + `ar' is considered a binary utility because archives of this sort +are most often used as "libraries" holding commonly needed subroutines. + + `ar' creates an index to the symbols defined in relocatable object +modules in the archive when you specify the modifier `s'. Once +created, this index is updated in the archive whenever `ar' makes a +change to its contents (save for the `q' update operation). An archive +with such an index speeds up linking to the library, and allows +routines in the library to call each other without regard to their +placement in the archive. + + You may use `nm -s' or `nm --print-armap' to list this index table. +If an archive lacks the table, another form of `ar' called `ranlib' can +be used to add just the table. + + GNU `ar' can optionally create a _thin_ archive, which contains a +symbol index and references to the original copies of the member files +of the archives. Such an archive is useful for building libraries for +use within a local build, where the relocatable objects are expected to +remain available, and copying the contents of each object would only +waste time and space. Thin archives are also _flattened_, so that +adding one or more archives to a thin archive will add the elements of +the nested archive individually. The paths to the elements of the +archive are stored relative to the archive itself. + + GNU `ar' is designed to be compatible with two different facilities. +You can control its activity using command-line options, like the +different varieties of `ar' on Unix systems; or, if you specify the +single command-line option `-M', you can control it with a script +supplied via standard input, like the MRI "librarian" program. + +* Menu: + +* ar cmdline:: Controlling `ar' on the command line +* ar scripts:: Controlling `ar' with a script + + +File: binutils.info, Node: ar cmdline, Next: ar scripts, Up: ar + +1.1 Controlling `ar' on the Command Line +======================================== + + ar [`--plugin' NAME] [`-X32_64'] [`-']P[MOD [RELPOS] [COUNT]] ARCHIVE [MEMBER...] + + When you use `ar' in the Unix style, `ar' insists on at least two +arguments to execute: one keyletter specifying the _operation_ +(optionally accompanied by other keyletters specifying _modifiers_), +and the archive name to act on. + + Most operations can also accept further MEMBER arguments, specifying +particular files to operate on. + + GNU `ar' allows you to mix the operation code P and modifier flags +MOD in any order, within the first command-line argument. + + If you wish, you may begin the first command-line argument with a +dash. + + The P keyletter specifies what operation to execute; it may be any +of the following, but you must specify only one of them: + +`d' + _Delete_ modules from the archive. Specify the names of modules to + be deleted as MEMBER...; the archive is untouched if you specify + no files to delete. + + If you specify the `v' modifier, `ar' lists each module as it is + deleted. + +`m' + Use this operation to _move_ members in an archive. + + The ordering of members in an archive can make a difference in how + programs are linked using the library, if a symbol is defined in + more than one member. + + If no modifiers are used with `m', any members you name in the + MEMBER arguments are moved to the _end_ of the archive; you can + use the `a', `b', or `i' modifiers to move them to a specified + place instead. + +`p' + _Print_ the specified members of the archive, to the standard + output file. If the `v' modifier is specified, show the member + name before copying its contents to standard output. + + If you specify no MEMBER arguments, all the files in the archive + are printed. + +`q' + _Quick append_; Historically, add the files MEMBER... to the end of + ARCHIVE, without checking for replacement. + + The modifiers `a', `b', and `i' do _not_ affect this operation; + new members are always placed at the end of the archive. + + The modifier `v' makes `ar' list each file as it is appended. + + Since the point of this operation is speed, the archive's symbol + table index is not updated, even if it already existed; you can + use `ar s' or `ranlib' explicitly to update the symbol table index. + + However, too many different systems assume quick append rebuilds + the index, so GNU `ar' implements `q' as a synonym for `r'. + +`r' + Insert the files MEMBER... into ARCHIVE (with _replacement_). This + operation differs from `q' in that any previously existing members + are deleted if their names match those being added. + + If one of the files named in MEMBER... does not exist, `ar' + displays an error message, and leaves undisturbed any existing + members of the archive matching that name. + + By default, new members are added at the end of the file; but you + may use one of the modifiers `a', `b', or `i' to request placement + relative to some existing member. + + The modifier `v' used with this operation elicits a line of output + for each file inserted, along with one of the letters `a' or `r' + to indicate whether the file was appended (no old member deleted) + or replaced. + +`t' + Display a _table_ listing the contents of ARCHIVE, or those of the + files listed in MEMBER... that are present in the archive. + Normally only the member name is shown; if you also want to see + the modes (permissions), timestamp, owner, group, and size, you can + request that by also specifying the `v' modifier. + + If you do not specify a MEMBER, all files in the archive are + listed. + + If there is more than one file with the same name (say, `fie') in + an archive (say `b.a'), `ar t b.a fie' lists only the first + instance; to see them all, you must ask for a complete listing--in + our example, `ar t b.a'. + +`x' + _Extract_ members (named MEMBER) from the archive. You can use + the `v' modifier with this operation, to request that `ar' list + each name as it extracts it. + + If you do not specify a MEMBER, all files in the archive are + extracted. + + Files cannot be extracted from a thin archive. + + + A number of modifiers (MOD) may immediately follow the P keyletter, +to specify variations on an operation's behavior: + +`a' + Add new files _after_ an existing member of the archive. If you + use the modifier `a', the name of an existing archive member must + be present as the RELPOS argument, before the ARCHIVE + specification. + +`b' + Add new files _before_ an existing member of the archive. If you + use the modifier `b', the name of an existing archive member must + be present as the RELPOS argument, before the ARCHIVE + specification. (same as `i'). + +`c' + _Create_ the archive. The specified ARCHIVE is always created if + it did not exist, when you request an update. But a warning is + issued unless you specify in advance that you expect to create it, + by using this modifier. + +`D' + Operate in _deterministic_ mode. When adding files and the archive + index use zero for UIDs, GIDs, timestamps, and use consistent file + modes for all files. When this option is used, if `ar' is used + with identical options and identical input files, multiple runs + will create identical output files regardless of the input files' + owners, groups, file modes, or modification times. + +`f' + Truncate names in the archive. GNU `ar' will normally permit file + names of any length. This will cause it to create archives which + are not compatible with the native `ar' program on some systems. + If this is a concern, the `f' modifier may be used to truncate file + names when putting them in the archive. + +`i' + Insert new files _before_ an existing member of the archive. If + you use the modifier `i', the name of an existing archive member + must be present as the RELPOS argument, before the ARCHIVE + specification. (same as `b'). + +`l' + This modifier is accepted but not used. + +`N' + Uses the COUNT parameter. This is used if there are multiple + entries in the archive with the same name. Extract or delete + instance COUNT of the given name from the archive. + +`o' + Preserve the _original_ dates of members when extracting them. If + you do not specify this modifier, files extracted from the archive + are stamped with the time of extraction. + +`P' + Use the full path name when matching names in the archive. GNU + `ar' can not create an archive with a full path name (such archives + are not POSIX complaint), but other archive creators can. This + option will cause GNU `ar' to match file names using a complete + path name, which can be convenient when extracting a single file + from an archive created by another tool. + +`s' + Write an object-file index into the archive, or update an existing + one, even if no other change is made to the archive. You may use + this modifier flag either with any operation, or alone. Running + `ar s' on an archive is equivalent to running `ranlib' on it. + +`S' + Do not generate an archive symbol table. This can speed up + building a large library in several steps. The resulting archive + can not be used with the linker. In order to build a symbol + table, you must omit the `S' modifier on the last execution of + `ar', or you must run `ranlib' on the archive. + +`T' + Make the specified ARCHIVE a _thin_ archive. If it already exists + and is a regular archive, the existing members must be present in + the same directory as ARCHIVE. + +`u' + Normally, `ar r'... inserts all files listed into the archive. If + you would like to insert _only_ those of the files you list that + are newer than existing members of the same names, use this + modifier. The `u' modifier is allowed only for the operation `r' + (replace). In particular, the combination `qu' is not allowed, + since checking the timestamps would lose any speed advantage from + the operation `q'. + +`v' + This modifier requests the _verbose_ version of an operation. Many + operations display additional information, such as filenames + processed, when the modifier `v' is appended. + +`V' + This modifier shows the version number of `ar'. + + `ar' ignores an initial option spelt `-X32_64', for compatibility +with AIX. The behaviour produced by this option is the default for GNU +`ar'. `ar' does not support any of the other `-X' options; in +particular, it does not support `-X32' which is the default for AIX +`ar'. + + The optional command line switch `--plugin' NAME causes `ar' to load +the plugin called NAME which adds support for more file formats. This +option is only available if the toolchain has been built with plugin +support enabled. + + +File: binutils.info, Node: ar scripts, Prev: ar cmdline, Up: ar + +1.2 Controlling `ar' with a Script +================================== + + ar -M [ <SCRIPT ] + + If you use the single command-line option `-M' with `ar', you can +control its operation with a rudimentary command language. This form +of `ar' operates interactively if standard input is coming directly +from a terminal. During interactive use, `ar' prompts for input (the +prompt is `AR >'), and continues executing even after errors. If you +redirect standard input to a script file, no prompts are issued, and +`ar' abandons execution (with a nonzero exit code) on any error. + + The `ar' command language is _not_ designed to be equivalent to the +command-line options; in fact, it provides somewhat less control over +archives. The only purpose of the command language is to ease the +transition to GNU `ar' for developers who already have scripts written +for the MRI "librarian" program. + + The syntax for the `ar' command language is straightforward: + * commands are recognized in upper or lower case; for example, `LIST' + is the same as `list'. In the following descriptions, commands are + shown in upper case for clarity. + + * a single command may appear on each line; it is the first word on + the line. + + * empty lines are allowed, and have no effect. + + * comments are allowed; text after either of the characters `*' or + `;' is ignored. + + * Whenever you use a list of names as part of the argument to an `ar' + command, you can separate the individual names with either commas + or blanks. Commas are shown in the explanations below, for + clarity. + + * `+' is used as a line continuation character; if `+' appears at + the end of a line, the text on the following line is considered + part of the current command. + + Here are the commands you can use in `ar' scripts, or when using +`ar' interactively. Three of them have special significance: + + `OPEN' or `CREATE' specify a "current archive", which is a temporary +file required for most of the other commands. + + `SAVE' commits the changes so far specified by the script. Prior to +`SAVE', commands affect only the temporary copy of the current archive. + +`ADDLIB ARCHIVE' +`ADDLIB ARCHIVE (MODULE, MODULE, ... MODULE)' + Add all the contents of ARCHIVE (or, if specified, each named + MODULE from ARCHIVE) to the current archive. + + Requires prior use of `OPEN' or `CREATE'. + +`ADDMOD MEMBER, MEMBER, ... MEMBER' + Add each named MEMBER as a module in the current archive. + + Requires prior use of `OPEN' or `CREATE'. + +`CLEAR' + Discard the contents of the current archive, canceling the effect + of any operations since the last `SAVE'. May be executed (with no + effect) even if no current archive is specified. + +`CREATE ARCHIVE' + Creates an archive, and makes it the current archive (required for + many other commands). The new archive is created with a temporary + name; it is not actually saved as ARCHIVE until you use `SAVE'. + You can overwrite existing archives; similarly, the contents of any + existing file named ARCHIVE will not be destroyed until `SAVE'. + +`DELETE MODULE, MODULE, ... MODULE' + Delete each listed MODULE from the current archive; equivalent to + `ar -d ARCHIVE MODULE ... MODULE'. + + Requires prior use of `OPEN' or `CREATE'. + +`DIRECTORY ARCHIVE (MODULE, ... MODULE)' +`DIRECTORY ARCHIVE (MODULE, ... MODULE) OUTPUTFILE' + List each named MODULE present in ARCHIVE. The separate command + `VERBOSE' specifies the form of the output: when verbose output is + off, output is like that of `ar -t ARCHIVE MODULE...'. When + verbose output is on, the listing is like `ar -tv ARCHIVE + MODULE...'. + + Output normally goes to the standard output stream; however, if you + specify OUTPUTFILE as a final argument, `ar' directs the output to + that file. + +`END' + Exit from `ar', with a `0' exit code to indicate successful + completion. This command does not save the output file; if you + have changed the current archive since the last `SAVE' command, + those changes are lost. + +`EXTRACT MODULE, MODULE, ... MODULE' + Extract each named MODULE from the current archive, writing them + into the current directory as separate files. Equivalent to `ar -x + ARCHIVE MODULE...'. + + Requires prior use of `OPEN' or `CREATE'. + +`LIST' + Display full contents of the current archive, in "verbose" style + regardless of the state of `VERBOSE'. The effect is like `ar tv + ARCHIVE'. (This single command is a GNU `ar' enhancement, rather + than present for MRI compatibility.) + + Requires prior use of `OPEN' or `CREATE'. + +`OPEN ARCHIVE' + Opens an existing archive for use as the current archive (required + for many other commands). Any changes as the result of subsequent + commands will not actually affect ARCHIVE until you next use + `SAVE'. + +`REPLACE MODULE, MODULE, ... MODULE' + In the current archive, replace each existing MODULE (named in the + `REPLACE' arguments) from files in the current working directory. + To execute this command without errors, both the file, and the + module in the current archive, must exist. + + Requires prior use of `OPEN' or `CREATE'. + +`VERBOSE' + Toggle an internal flag governing the output from `DIRECTORY'. + When the flag is on, `DIRECTORY' output matches output from `ar + -tv '.... + +`SAVE' + Commit your changes to the current archive, and actually save it + as a file with the name specified in the last `CREATE' or `OPEN' + command. + + Requires prior use of `OPEN' or `CREATE'. + + + +File: binutils.info, Node: nm, Next: objcopy, Prev: ar, Up: Top + +2 nm +**** + + nm [`-a'|`--debug-syms'] + [`-g'|`--extern-only'][`--plugin' NAME] + [`-B'] [`-C'|`--demangle'[=STYLE]] [`-D'|`--dynamic'] + [`-S'|`--print-size'] [`-s'|`--print-armap'] + [`-A'|`-o'|`--print-file-name'][`--special-syms'] + [`-n'|`-v'|`--numeric-sort'] [`-p'|`--no-sort'] + [`-r'|`--reverse-sort'] [`--size-sort'] [`-u'|`--undefined-only'] + [`-t' RADIX|`--radix='RADIX] [`-P'|`--portability'] + [`--target='BFDNAME] [`-f'FORMAT|`--format='FORMAT] + [`--defined-only'] [`-l'|`--line-numbers'] [`--no-demangle'] + [`-V'|`--version'] [`-X 32_64'] [`--help'] [OBJFILE...] + + GNU `nm' lists the symbols from object files OBJFILE.... If no +object files are listed as arguments, `nm' assumes the file `a.out'. + + For each symbol, `nm' shows: + + * The symbol value, in the radix selected by options (see below), or + hexadecimal by default. + + * The symbol type. At least the following types are used; others + are, as well, depending on the object file format. If lowercase, + the symbol is local; if uppercase, the symbol is global (external). + + `A' + The symbol's value is absolute, and will not be changed by + further linking. + + `B' + `b' + The symbol is in the uninitialized data section (known as + BSS). + + `C' + The symbol is common. Common symbols are uninitialized data. + When linking, multiple common symbols may appear with the + same name. If the symbol is defined anywhere, the common + symbols are treated as undefined references. For more + details on common symbols, see the discussion of -warn-common + in *Note Linker options: (ld.info)Options. + + `D' + `d' + The symbol is in the initialized data section. + + `G' + `g' + The symbol is in an initialized data section for small + objects. Some object file formats permit more efficient + access to small data objects, such as a global int variable + as opposed to a large global array. + + `i' + For PE format files this indicates that the symbol is in a + section specific to the implementation of DLLs. For ELF + format files this indicates that the symbol is an indirect + function. This is a GNU extension to the standard set of ELF + symbol types. It indicates a symbol which if referenced by a + relocation does not evaluate to its address, but instead must + be invoked at runtime. The runtime execution will then + return the value to be used in the relocation. + + `N' + The symbol is a debugging symbol. + + `p' + The symbols is in a stack unwind section. + + `R' + `r' + The symbol is in a read only data section. + + `S' + `s' + The symbol is in an uninitialized data section for small + objects. + + `T' + `t' + The symbol is in the text (code) section. + + `U' + The symbol is undefined. + + `u' + The symbol is a unique global symbol. This is a GNU + extension to the standard set of ELF symbol bindings. For + such a symbol the dynamic linker will make sure that in the + entire process there is just one symbol with this name and + type in use. + + `V' + `v' + The symbol is a weak object. When a weak defined symbol is + linked with a normal defined symbol, the normal defined + symbol is used with no error. When a weak undefined symbol + is linked and the symbol is not defined, the value of the + weak symbol becomes zero with no error. On some systems, + uppercase indicates that a default value has been specified. + + `W' + `w' + The symbol is a weak symbol that has not been specifically + tagged as a weak object symbol. When a weak defined symbol + is linked with a normal defined symbol, the normal defined + symbol is used with no error. When a weak undefined symbol + is linked and the symbol is not defined, the value of the + symbol is determined in a system-specific manner without + error. On some systems, uppercase indicates that a default + value has been specified. + + `-' + The symbol is a stabs symbol in an a.out object file. In + this case, the next values printed are the stabs other field, + the stabs desc field, and the stab type. Stabs symbols are + used to hold debugging information. For more information, + see *Note Stabs: (stabs.info)Top. + + `?' + The symbol type is unknown, or object file format specific. + + * The symbol name. + + The long and short forms of options, shown here as alternatives, are +equivalent. + +`-A' +`-o' +`--print-file-name' + Precede each symbol by the name of the input file (or archive + member) in which it was found, rather than identifying the input + file once only, before all of its symbols. + +`-a' +`--debug-syms' + Display all symbols, even debugger-only symbols; normally these + are not listed. + +`-B' + The same as `--format=bsd' (for compatibility with the MIPS `nm'). + +`-C' +`--demangle[=STYLE]' + Decode ("demangle") low-level symbol names into user-level names. + Besides removing any initial underscore prepended by the system, + this makes C++ function names readable. Different compilers have + different mangling styles. The optional demangling style argument + can be used to choose an appropriate demangling style for your + compiler. *Note c++filt::, for more information on demangling. + +`--no-demangle' + Do not demangle low-level symbol names. This is the default. + +`-D' +`--dynamic' + Display the dynamic symbols rather than the normal symbols. This + is only meaningful for dynamic objects, such as certain types of + shared libraries. + +`-f FORMAT' +`--format=FORMAT' + Use the output format FORMAT, which can be `bsd', `sysv', or + `posix'. The default is `bsd'. Only the first character of + FORMAT is significant; it can be either upper or lower case. + +`-g' +`--extern-only' + Display only external symbols. + +`--plugin NAME' + Load the plugin called NAME to add support for extra target types. + This option is only available if the toolchain has been built + with plugin support enabled. + +`-l' +`--line-numbers' + For each symbol, use debugging information to try to find a + filename and line number. For a defined symbol, look for the line + number of the address of the symbol. For an undefined symbol, + look for the line number of a relocation entry which refers to the + symbol. If line number information can be found, print it after + the other symbol information. + +`-n' +`-v' +`--numeric-sort' + Sort symbols numerically by their addresses, rather than + alphabetically by their names. + +`-p' +`--no-sort' + Do not bother to sort the symbols in any order; print them in the + order encountered. + +`-P' +`--portability' + Use the POSIX.2 standard output format instead of the default + format. Equivalent to `-f posix'. + +`-S' +`--print-size' + Print both value and size of defined symbols for the `bsd' output + style. This option has no effect for object formats that do not + record symbol sizes, unless `--size-sort' is also used in which + case a calculated size is displayed. + +`-s' +`--print-armap' + When listing symbols from archive members, include the index: a + mapping (stored in the archive by `ar' or `ranlib') of which + modules contain definitions for which names. + +`-r' +`--reverse-sort' + Reverse the order of the sort (whether numeric or alphabetic); let + the last come first. + +`--size-sort' + Sort symbols by size. The size is computed as the difference + between the value of the symbol and the value of the symbol with + the next higher value. If the `bsd' output format is used the + size of the symbol is printed, rather than the value, and `-S' + must be used in order both size and value to be printed. + +`--special-syms' + Display symbols which have a target-specific special meaning. + These symbols are usually used by the target for some special + processing and are not normally helpful when included included in + the normal symbol lists. For example for ARM targets this option + would skip the mapping symbols used to mark transitions between + ARM code, THUMB code and data. + +`-t RADIX' +`--radix=RADIX' + Use RADIX as the radix for printing the symbol values. It must be + `d' for decimal, `o' for octal, or `x' for hexadecimal. + +`--target=BFDNAME' + Specify an object code format other than your system's default + format. *Note Target Selection::, for more information. + +`-u' +`--undefined-only' + Display only undefined symbols (those external to each object + file). + +`--defined-only' + Display only defined symbols for each object file. + +`-V' +`--version' + Show the version number of `nm' and exit. + +`-X' + This option is ignored for compatibility with the AIX version of + `nm'. It takes one parameter which must be the string `32_64'. + The default mode of AIX `nm' corresponds to `-X 32', which is not + supported by GNU `nm'. + +`--help' + Show a summary of the options to `nm' and exit. + + +File: binutils.info, Node: objcopy, Next: objdump, Prev: nm, Up: Top + +3 objcopy +********* + + objcopy [`-F' BFDNAME|`--target='BFDNAME] + [`-I' BFDNAME|`--input-target='BFDNAME] + [`-O' BFDNAME|`--output-target='BFDNAME] + [`-B' BFDARCH|`--binary-architecture='BFDARCH] + [`-S'|`--strip-all'] + [`-g'|`--strip-debug'] + [`-K' SYMBOLNAME|`--keep-symbol='SYMBOLNAME] + [`-N' SYMBOLNAME|`--strip-symbol='SYMBOLNAME] + [`--strip-unneeded-symbol='SYMBOLNAME] + [`-G' SYMBOLNAME|`--keep-global-symbol='SYMBOLNAME] + [`--localize-hidden'] + [`-L' SYMBOLNAME|`--localize-symbol='SYMBOLNAME] + [`--globalize-symbol='SYMBOLNAME] + [`-W' SYMBOLNAME|`--weaken-symbol='SYMBOLNAME] + [`-w'|`--wildcard'] + [`-x'|`--discard-all'] + [`-X'|`--discard-locals'] + [`-b' BYTE|`--byte='BYTE] + [`-i' INTERLEAVE|`--interleave='INTERLEAVE] + [`-j' SECTIONNAME|`--only-section='SECTIONNAME] + [`-R' SECTIONNAME|`--remove-section='SECTIONNAME] + [`-p'|`--preserve-dates'] + [`--debugging'] + [`--gap-fill='VAL] + [`--pad-to='ADDRESS] + [`--set-start='VAL] + [`--adjust-start='INCR] + [`--change-addresses='INCR] + [`--change-section-address' SECTION{=,+,-}VAL] + [`--change-section-lma' SECTION{=,+,-}VAL] + [`--change-section-vma' SECTION{=,+,-}VAL] + [`--change-warnings'] [`--no-change-warnings'] + [`--set-section-flags' SECTION=FLAGS] + [`--add-section' SECTIONNAME=FILENAME] + [`--rename-section' OLDNAME=NEWNAME[,FLAGS]] + [`--long-section-names' {enable,disable,keep}] + [`--change-leading-char'] [`--remove-leading-char'] + [`--reverse-bytes='NUM] + [`--srec-len='IVAL] [`--srec-forceS3'] + [`--redefine-sym' OLD=NEW] + [`--redefine-syms='FILENAME] + [`--weaken'] + [`--keep-symbols='FILENAME] + [`--strip-symbols='FILENAME] + [`--strip-unneeded-symbols='FILENAME] + [`--keep-global-symbols='FILENAME] + [`--localize-symbols='FILENAME] + [`--globalize-symbols='FILENAME] + [`--weaken-symbols='FILENAME] + [`--alt-machine-code='INDEX] + [`--prefix-symbols='STRING] + [`--prefix-sections='STRING] + [`--prefix-alloc-sections='STRING] + [`--add-gnu-debuglink='PATH-TO-FILE] + [`--keep-file-symbols'] + [`--only-keep-debug'] + [`--extract-symbol'] + [`--writable-text'] + [`--readonly-text'] + [`--pure'] + [`--impure'] + [`--file-alignment='NUM] + [`--heap='SIZE] + [`--image-base='ADDRESS] + [`--section-alignment='NUM] + [`--stack='SIZE] + [`--subsystem='WHICH:MAJOR.MINOR] + [`-v'|`--verbose'] + [`-V'|`--version'] + [`--help'] [`--info'] + INFILE [OUTFILE] + + The GNU `objcopy' utility copies the contents of an object file to +another. `objcopy' uses the GNU BFD Library to read and write the +object files. It can write the destination object file in a format +different from that of the source object file. The exact behavior of +`objcopy' is controlled by command-line options. Note that `objcopy' +should be able to copy a fully linked file between any two formats. +However, copying a relocatable object file between any two formats may +not work as expected. + + `objcopy' creates temporary files to do its translations and deletes +them afterward. `objcopy' uses BFD to do all its translation work; it +has access to all the formats described in BFD and thus is able to +recognize most formats without being told explicitly. *Note BFD: +(ld.info)BFD. + + `objcopy' can be used to generate S-records by using an output +target of `srec' (e.g., use `-O srec'). + + `objcopy' can be used to generate a raw binary file by using an +output target of `binary' (e.g., use `-O binary'). When `objcopy' +generates a raw binary file, it will essentially produce a memory dump +of the contents of the input object file. All symbols and relocation +information will be discarded. The memory dump will start at the load +address of the lowest section copied into the output file. + + When generating an S-record or a raw binary file, it may be helpful +to use `-S' to remove sections containing debugging information. In +some cases `-R' will be useful to remove sections which contain +information that is not needed by the binary file. + + Note--`objcopy' is not able to change the endianness of its input +files. If the input format has an endianness (some formats do not), +`objcopy' can only copy the inputs into file formats that have the same +endianness or which have no endianness (e.g., `srec'). (However, see +the `--reverse-bytes' option.) + +`INFILE' +`OUTFILE' + The input and output files, respectively. If you do not specify + OUTFILE, `objcopy' creates a temporary file and destructively + renames the result with the name of INFILE. + +`-I BFDNAME' +`--input-target=BFDNAME' + Consider the source file's object format to be BFDNAME, rather than + attempting to deduce it. *Note Target Selection::, for more + information. + +`-O BFDNAME' +`--output-target=BFDNAME' + Write the output file using the object format BFDNAME. *Note + Target Selection::, for more information. + +`-F BFDNAME' +`--target=BFDNAME' + Use BFDNAME as the object format for both the input and the output + file; i.e., simply transfer data from source to destination with no + translation. *Note Target Selection::, for more information. + +`-B BFDARCH' +`--binary-architecture=BFDARCH' + Useful when transforming a raw binary input file into an object + file. In this case the output architecture can be set to BFDARCH. + This option will be ignored if the input file has a known BFDARCH. + You can access this binary data inside a program by referencing + the special symbols that are created by the conversion process. + These symbols are called _binary_OBJFILE_start, + _binary_OBJFILE_end and _binary_OBJFILE_size. e.g. you can + transform a picture file into an object file and then access it in + your code using these symbols. + +`-j SECTIONNAME' +`--only-section=SECTIONNAME' + Copy only the named section from the input file to the output file. + This option may be given more than once. Note that using this + option inappropriately may make the output file unusable. + +`-R SECTIONNAME' +`--remove-section=SECTIONNAME' + Remove any section named SECTIONNAME from the output file. This + option may be given more than once. Note that using this option + inappropriately may make the output file unusable. + +`-S' +`--strip-all' + Do not copy relocation and symbol information from the source file. + +`-g' +`--strip-debug' + Do not copy debugging symbols or sections from the source file. + +`--strip-unneeded' + Strip all symbols that are not needed for relocation processing. + +`-K SYMBOLNAME' +`--keep-symbol=SYMBOLNAME' + When stripping symbols, keep symbol SYMBOLNAME even if it would + normally be stripped. This option may be given more than once. + +`-N SYMBOLNAME' +`--strip-symbol=SYMBOLNAME' + Do not copy symbol SYMBOLNAME from the source file. This option + may be given more than once. + +`--strip-unneeded-symbol=SYMBOLNAME' + Do not copy symbol SYMBOLNAME from the source file unless it is + needed by a relocation. This option may be given more than once. + +`-G SYMBOLNAME' +`--keep-global-symbol=SYMBOLNAME' + Keep only symbol SYMBOLNAME global. Make all other symbols local + to the file, so that they are not visible externally. This option + may be given more than once. + +`--localize-hidden' + In an ELF object, mark all symbols that have hidden or internal + visibility as local. This option applies on top of + symbol-specific localization options such as `-L'. + +`-L SYMBOLNAME' +`--localize-symbol=SYMBOLNAME' + Make symbol SYMBOLNAME local to the file, so that it is not + visible externally. This option may be given more than once. + +`-W SYMBOLNAME' +`--weaken-symbol=SYMBOLNAME' + Make symbol SYMBOLNAME weak. This option may be given more than + once. + +`--globalize-symbol=SYMBOLNAME' + Give symbol SYMBOLNAME global scoping so that it is visible + outside of the file in which it is defined. This option may be + given more than once. + +`-w' +`--wildcard' + Permit regular expressions in SYMBOLNAMEs used in other command + line options. The question mark (?), asterisk (*), backslash (\) + and square brackets ([]) operators can be used anywhere in the + symbol name. If the first character of the symbol name is the + exclamation point (!) then the sense of the switch is reversed for + that symbol. For example: + + -w -W !foo -W fo* + + would cause objcopy to weaken all symbols that start with "fo" + except for the symbol "foo". + +`-x' +`--discard-all' + Do not copy non-global symbols from the source file. + +`-X' +`--discard-locals' + Do not copy compiler-generated local symbols. (These usually + start with `L' or `.'.) + +`-b BYTE' +`--byte=BYTE' + Keep only every BYTEth byte of the input file (header data is not + affected). BYTE can be in the range from 0 to INTERLEAVE-1, where + INTERLEAVE is given by the `-i' or `--interleave' option, or the + default of 4. This option is useful for creating files to program + ROM. It is typically used with an `srec' output target. + +`-i INTERLEAVE' +`--interleave=INTERLEAVE' + Only copy one out of every INTERLEAVE bytes. Select which byte to + copy with the `-b' or `--byte' option. The default is 4. + `objcopy' ignores this option if you do not specify either `-b' or + `--byte'. + +`-p' +`--preserve-dates' + Set the access and modification dates of the output file to be the + same as those of the input file. + +`--debugging' + Convert debugging information, if possible. This is not the + default because only certain debugging formats are supported, and + the conversion process can be time consuming. + +`--gap-fill VAL' + Fill gaps between sections with VAL. This operation applies to + the _load address_ (LMA) of the sections. It is done by increasing + the size of the section with the lower address, and filling in the + extra space created with VAL. + +`--pad-to ADDRESS' + Pad the output file up to the load address ADDRESS. This is done + by increasing the size of the last section. The extra space is + filled in with the value specified by `--gap-fill' (default zero). + +`--set-start VAL' + Set the start address of the new file to VAL. Not all object file + formats support setting the start address. + +`--change-start INCR' +`--adjust-start INCR' + Change the start address by adding INCR. Not all object file + formats support setting the start address. + +`--change-addresses INCR' +`--adjust-vma INCR' + Change the VMA and LMA addresses of all sections, as well as the + start address, by adding INCR. Some object file formats do not + permit section addresses to be changed arbitrarily. Note that + this does not relocate the sections; if the program expects + sections to be loaded at a certain address, and this option is + used to change the sections such that they are loaded at a + different address, the program may fail. + +`--change-section-address SECTION{=,+,-}VAL' +`--adjust-section-vma SECTION{=,+,-}VAL' + Set or change both the VMA address and the LMA address of the named + SECTION. If `=' is used, the section address is set to VAL. + Otherwise, VAL is added to or subtracted from the section address. + See the comments under `--change-addresses', above. If SECTION + does not exist in the input file, a warning will be issued, unless + `--no-change-warnings' is used. + +`--change-section-lma SECTION{=,+,-}VAL' + Set or change the LMA address of the named SECTION. The LMA + address is the address where the section will be loaded into + memory at program load time. Normally this is the same as the VMA + address, which is the address of the section at program run time, + but on some systems, especially those where a program is held in + ROM, the two can be different. If `=' is used, the section + address is set to VAL. Otherwise, VAL is added to or subtracted + from the section address. See the comments under + `--change-addresses', above. If SECTION does not exist in the + input file, a warning will be issued, unless + `--no-change-warnings' is used. + +`--change-section-vma SECTION{=,+,-}VAL' + Set or change the VMA address of the named SECTION. The VMA + address is the address where the section will be located once the + program has started executing. Normally this is the same as the + LMA address, which is the address where the section will be loaded + into memory, but on some systems, especially those where a program + is held in ROM, the two can be different. If `=' is used, the + section address is set to VAL. Otherwise, VAL is added to or + subtracted from the section address. See the comments under + `--change-addresses', above. If SECTION does not exist in the + input file, a warning will be issued, unless + `--no-change-warnings' is used. + +`--change-warnings' +`--adjust-warnings' + If `--change-section-address' or `--change-section-lma' or + `--change-section-vma' is used, and the named section does not + exist, issue a warning. This is the default. + +`--no-change-warnings' +`--no-adjust-warnings' + Do not issue a warning if `--change-section-address' or + `--adjust-section-lma' or `--adjust-section-vma' is used, even if + the named section does not exist. + +`--set-section-flags SECTION=FLAGS' + Set the flags for the named section. The FLAGS argument is a + comma separated string of flag names. The recognized names are + `alloc', `contents', `load', `noload', `readonly', `code', `data', + `rom', `share', and `debug'. You can set the `contents' flag for + a section which does not have contents, but it is not meaningful + to clear the `contents' flag of a section which does have + contents-just remove the section instead. Not all flags are + meaningful for all object file formats. + +`--add-section SECTIONNAME=FILENAME' + Add a new section named SECTIONNAME while copying the file. The + contents of the new section are taken from the file FILENAME. The + size of the section will be the size of the file. This option only + works on file formats which can support sections with arbitrary + names. + +`--rename-section OLDNAME=NEWNAME[,FLAGS]' + Rename a section from OLDNAME to NEWNAME, optionally changing the + section's flags to FLAGS in the process. This has the advantage + over usng a linker script to perform the rename in that the output + stays as an object file and does not become a linked executable. + + This option is particularly helpful when the input format is + binary, since this will always create a section called .data. If + for example, you wanted instead to create a section called .rodata + containing binary data you could use the following command line to + achieve it: + + objcopy -I binary -O <output_format> -B <architecture> \ + --rename-section .data=.rodata,alloc,load,readonly,data,contents \ + <input_binary_file> <output_object_file> + +`--long-section-names {enable,disable,keep}' + Controls the handling of long section names when processing `COFF' + and `PE-COFF' object formats. The default behaviour, `keep', is + to preserve long section names if any are present in the input + file. The `enable' and `disable' options forcibly enable or + disable the use of long section names in the output object; when + `disable' is in effect, any long section names in the input object + will be truncated. The `enable' option will only emit long + section names if any are present in the inputs; this is mostly the + same as `keep', but it is left undefined whether the `enable' + option might force the creation of an empty string table in the + output file. + +`--change-leading-char' + Some object file formats use special characters at the start of + symbols. The most common such character is underscore, which + compilers often add before every symbol. This option tells + `objcopy' to change the leading character of every symbol when it + converts between object file formats. If the object file formats + use the same leading character, this option has no effect. + Otherwise, it will add a character, or remove a character, or + change a character, as appropriate. + +`--remove-leading-char' + If the first character of a global symbol is a special symbol + leading character used by the object file format, remove the + character. The most common symbol leading character is + underscore. This option will remove a leading underscore from all + global symbols. This can be useful if you want to link together + objects of different file formats with different conventions for + symbol names. This is different from `--change-leading-char' + because it always changes the symbol name when appropriate, + regardless of the object file format of the output file. + +`--reverse-bytes=NUM' + Reverse the bytes in a section with output contents. A section + length must be evenly divisible by the value given in order for + the swap to be able to take place. Reversing takes place before + the interleaving is performed. + + This option is used typically in generating ROM images for + problematic target systems. For example, on some target boards, + the 32-bit words fetched from 8-bit ROMs are re-assembled in + little-endian byte order regardless of the CPU byte order. + Depending on the programming model, the endianness of the ROM may + need to be modified. + + Consider a simple file with a section containing the following + eight bytes: `12345678'. + + Using `--reverse-bytes=2' for the above example, the bytes in the + output file would be ordered `21436587'. + + Using `--reverse-bytes=4' for the above example, the bytes in the + output file would be ordered `43218765'. + + By using `--reverse-bytes=2' for the above example, followed by + `--reverse-bytes=4' on the output file, the bytes in the second + output file would be ordered `34127856'. + +`--srec-len=IVAL' + Meaningful only for srec output. Set the maximum length of the + Srecords being produced to IVAL. This length covers both address, + data and crc fields. + +`--srec-forceS3' + Meaningful only for srec output. Avoid generation of S1/S2 + records, creating S3-only record format. + +`--redefine-sym OLD=NEW' + Change the name of a symbol OLD, to NEW. This can be useful when + one is trying link two things together for which you have no + source, and there are name collisions. + +`--redefine-syms=FILENAME' + Apply `--redefine-sym' to each symbol pair "OLD NEW" listed in the + file FILENAME. FILENAME is simply a flat file, with one symbol + pair per line. Line comments may be introduced by the hash + character. This option may be given more than once. + +`--weaken' + Change all global symbols in the file to be weak. This can be + useful when building an object which will be linked against other + objects using the `-R' option to the linker. This option is only + effective when using an object file format which supports weak + symbols. + +`--keep-symbols=FILENAME' + Apply `--keep-symbol' option to each symbol listed in the file + FILENAME. FILENAME is simply a flat file, with one symbol name + per line. Line comments may be introduced by the hash character. + This option may be given more than once. + +`--strip-symbols=FILENAME' + Apply `--strip-symbol' option to each symbol listed in the file + FILENAME. FILENAME is simply a flat file, with one symbol name + per line. Line comments may be introduced by the hash character. + This option may be given more than once. + +`--strip-unneeded-symbols=FILENAME' + Apply `--strip-unneeded-symbol' option to each symbol listed in + the file FILENAME. FILENAME is simply a flat file, with one + symbol name per line. Line comments may be introduced by the hash + character. This option may be given more than once. + +`--keep-global-symbols=FILENAME' + Apply `--keep-global-symbol' option to each symbol listed in the + file FILENAME. FILENAME is simply a flat file, with one symbol + name per line. Line comments may be introduced by the hash + character. This option may be given more than once. + +`--localize-symbols=FILENAME' + Apply `--localize-symbol' option to each symbol listed in the file + FILENAME. FILENAME is simply a flat file, with one symbol name + per line. Line comments may be introduced by the hash character. + This option may be given more than once. + +`--globalize-symbols=FILENAME' + Apply `--globalize-symbol' option to each symbol listed in the file + FILENAME. FILENAME is simply a flat file, with one symbol name + per line. Line comments may be introduced by the hash character. + This option may be given more than once. + +`--weaken-symbols=FILENAME' + Apply `--weaken-symbol' option to each symbol listed in the file + FILENAME. FILENAME is simply a flat file, with one symbol name + per line. Line comments may be introduced by the hash character. + This option may be given more than once. + +`--alt-machine-code=INDEX' + If the output architecture has alternate machine codes, use the + INDEXth code instead of the default one. This is useful in case a + machine is assigned an official code and the tool-chain adopts the + new code, but other applications still depend on the original code + being used. For ELF based architectures if the INDEX alternative + does not exist then the value is treated as an absolute number to + be stored in the e_machine field of the ELF header. + +`--writable-text' + Mark the output text as writable. This option isn't meaningful + for all object file formats. + +`--readonly-text' + Make the output text write protected. This option isn't + meaningful for all object file formats. + +`--pure' + Mark the output file as demand paged. This option isn't + meaningful for all object file formats. + +`--impure' + Mark the output file as impure. This option isn't meaningful for + all object file formats. + +`--prefix-symbols=STRING' + Prefix all symbols in the output file with STRING. + +`--prefix-sections=STRING' + Prefix all section names in the output file with STRING. + +`--prefix-alloc-sections=STRING' + Prefix all the names of all allocated sections in the output file + with STRING. + +`--add-gnu-debuglink=PATH-TO-FILE' + Creates a .gnu_debuglink section which contains a reference to + PATH-TO-FILE and adds it to the output file. + +`--keep-file-symbols' + When stripping a file, perhaps with `--strip-debug' or + `--strip-unneeded', retain any symbols specifying source file + names, which would otherwise get stripped. + +`--only-keep-debug' + Strip a file, removing contents of any sections that would not be + stripped by `--strip-debug' and leaving the debugging sections + intact. In ELF files, this preserves all note sections in the + output. + + The intention is that this option will be used in conjunction with + `--add-gnu-debuglink' to create a two part executable. One a + stripped binary which will occupy less space in RAM and in a + distribution and the second a debugging information file which is + only needed if debugging abilities are required. The suggested + procedure to create these files is as follows: + + 1. Link the executable as normal. Assuming that is is called + `foo' then... + + 2. Run `objcopy --only-keep-debug foo foo.dbg' to create a file + containing the debugging info. + + 3. Run `objcopy --strip-debug foo' to create a stripped + executable. + + 4. Run `objcopy --add-gnu-debuglink=foo.dbg foo' to add a link + to the debugging info into the stripped executable. + + Note--the choice of `.dbg' as an extension for the debug info file + is arbitrary. Also the `--only-keep-debug' step is optional. You + could instead do this: + + 1. Link the executable as normal. + + 2. Copy `foo' to `foo.full' + + 3. Run `objcopy --strip-debug foo' + + 4. Run `objcopy --add-gnu-debuglink=foo.full foo' + + i.e., the file pointed to by the `--add-gnu-debuglink' can be the + full executable. It does not have to be a file created by the + `--only-keep-debug' switch. + + Note--this switch is only intended for use on fully linked files. + It does not make sense to use it on object files where the + debugging information may be incomplete. Besides the + gnu_debuglink feature currently only supports the presence of one + filename containing debugging information, not multiple filenames + on a one-per-object-file basis. + +`--file-alignment NUM' + Specify the file alignment. Sections in the file will always + begin at file offsets which are multiples of this number. This + defaults to 512. [This option is specific to PE targets.] + +`--heap RESERVE' +`--heap RESERVE,COMMIT' + Specify the number of bytes of memory to reserve (and optionally + commit) to be used as heap for this program. [This option is + specific to PE targets.] + +`--image-base VALUE' + Use VALUE as the base address of your program or dll. This is the + lowest memory location that will be used when your program or dll + is loaded. To reduce the need to relocate and improve performance + of your dlls, each should have a unique base address and not + overlap any other dlls. The default is 0x400000 for executables, + and 0x10000000 for dlls. [This option is specific to PE targets.] + +`--section-alignment NUM' + Sets the section alignment. Sections in memory will always begin + at addresses which are a multiple of this number. Defaults to + 0x1000. [This option is specific to PE targets.] + +`--stack RESERVE' +`--stack RESERVE,COMMIT' + Specify the number of bytes of memory to reserve (and optionally + commit) to be used as stack for this program. [This option is + specific to PE targets.] + +`--subsystem WHICH' +`--subsystem WHICH:MAJOR' +`--subsystem WHICH:MAJOR.MINOR' + Specifies the subsystem under which your program will execute. The + legal values for WHICH are `native', `windows', `console', + `posix', `efi-app', `efi-bsd', `efi-rtd', `sal-rtd', and `xbox'. + You may optionally set the subsystem version also. Numeric values + are also accepted for WHICH. [This option is specific to PE + targets.] + +`--extract-symbol' + Keep the file's section flags and symbols but remove all section + data. Specifically, the option: + + * removes the contents of all sections; + + * sets the size of every section to zero; and + + * sets the file's start address to zero. + + This option is used to build a `.sym' file for a VxWorks kernel. + It can also be a useful way of reducing the size of a + `--just-symbols' linker input file. + +`-V' +`--version' + Show the version number of `objcopy'. + +`-v' +`--verbose' + Verbose output: list all object files modified. In the case of + archives, `objcopy -V' lists all members of the archive. + +`--help' + Show a summary of the options to `objcopy'. + +`--info' + Display a list showing all architectures and object formats + available. + + +File: binutils.info, Node: objdump, Next: ranlib, Prev: objcopy, Up: Top + +4 objdump +********* + + objdump [`-a'|`--archive-headers'] + [`-b' BFDNAME|`--target=BFDNAME'] + [`-C'|`--demangle'[=STYLE] ] + [`-d'|`--disassemble'] + [`-D'|`--disassemble-all'] + [`-z'|`--disassemble-zeroes'] + [`-EB'|`-EL'|`--endian='{big | little }] + [`-f'|`--file-headers'] + [`-F'|`--file-offsets'] + [`--file-start-context'] + [`-g'|`--debugging'] + [`-e'|`--debugging-tags'] + [`-h'|`--section-headers'|`--headers'] + [`-i'|`--info'] + [`-j' SECTION|`--section='SECTION] + [`-l'|`--line-numbers'] + [`-S'|`--source'] + [`-m' MACHINE|`--architecture='MACHINE] + [`-M' OPTIONS|`--disassembler-options='OPTIONS] + [`-p'|`--private-headers'] + [`-r'|`--reloc'] + [`-R'|`--dynamic-reloc'] + [`-s'|`--full-contents'] + [`-W[lLiaprmfFsoR]'| + `--dwarf'[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges]] + [`-G'|`--stabs'] + [`-t'|`--syms'] + [`-T'|`--dynamic-syms'] + [`-x'|`--all-headers'] + [`-w'|`--wide'] + [`--start-address='ADDRESS] + [`--stop-address='ADDRESS] + [`--prefix-addresses'] + [`--[no-]show-raw-insn'] + [`--adjust-vma='OFFSET] + [`--special-syms'] + [`--prefix='PREFIX] + [`--prefix-strip='LEVEL] + [`--insn-width='WIDTH] + [`-V'|`--version'] + [`-H'|`--help'] + OBJFILE... + + `objdump' displays information about one or more object files. The +options control what particular information to display. This +information is mostly useful to programmers who are working on the +compilation tools, as opposed to programmers who just want their +program to compile and work. + + OBJFILE... are the object files to be examined. When you specify +archives, `objdump' shows information on each of the member object +files. + + The long and short forms of options, shown here as alternatives, are +equivalent. At least one option from the list +`-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-r,-R,-s,-S,-t,-T,-V,-x' must be given. + +`-a' +`--archive-header' + If any of the OBJFILE files are archives, display the archive + header information (in a format similar to `ls -l'). Besides the + information you could list with `ar tv', `objdump -a' shows the + object file format of each archive member. + +`--adjust-vma=OFFSET' + When dumping information, first add OFFSET to all the section + addresses. This is useful if the section addresses do not + correspond to the symbol table, which can happen when putting + sections at particular addresses when using a format which can not + represent section addresses, such as a.out. + +`-b BFDNAME' +`--target=BFDNAME' + Specify that the object-code format for the object files is + BFDNAME. This option may not be necessary; OBJDUMP can + automatically recognize many formats. + + For example, + objdump -b oasys -m vax -h fu.o + displays summary information from the section headers (`-h') of + `fu.o', which is explicitly identified (`-m') as a VAX object file + in the format produced by Oasys compilers. You can list the + formats available with the `-i' option. *Note Target Selection::, + for more information. + +`-C' +`--demangle[=STYLE]' + Decode ("demangle") low-level symbol names into user-level names. + Besides removing any initial underscore prepended by the system, + this makes C++ function names readable. Different compilers have + different mangling styles. The optional demangling style argument + can be used to choose an appropriate demangling style for your + compiler. *Note c++filt::, for more information on demangling. + +`-g' +`--debugging' + Display debugging information. This attempts to parse STABS and + IEEE debugging format information stored in the file and print it + out using a C like syntax. If neither of these formats are found + this option falls back on the `-W' option to print any DWARF + information in the file. + +`-e' +`--debugging-tags' + Like `-g', but the information is generated in a format compatible + with ctags tool. + +`-d' +`--disassemble' + Display the assembler mnemonics for the machine instructions from + OBJFILE. This option only disassembles those sections which are + expected to contain instructions. + +`-D' +`--disassemble-all' + Like `-d', but disassemble the contents of all sections, not just + those expected to contain instructions. + + If the target is an ARM architecture this switch also has the + effect of forcing the disassembler to decode pieces of data found + in code sections as if they were instructions. + +`--prefix-addresses' + When disassembling, print the complete address on each line. This + is the older disassembly format. + +`-EB' +`-EL' +`--endian={big|little}' + Specify the endianness of the object files. This only affects + disassembly. This can be useful when disassembling a file format + which does not describe endianness information, such as S-records. + +`-f' +`--file-headers' + Display summary information from the overall header of each of the + OBJFILE files. + +`-F' +`--file-offsets' + When disassembling sections, whenever a symbol is displayed, also + display the file offset of the region of data that is about to be + dumped. If zeroes are being skipped, then when disassembly + resumes, tell the user how many zeroes were skipped and the file + offset of the location from where the disassembly resumes. When + dumping sections, display the file offset of the location from + where the dump starts. + +`--file-start-context' + Specify that when displaying interlisted source code/disassembly + (assumes `-S') from a file that has not yet been displayed, extend + the context to the start of the file. + +`-h' +`--section-headers' +`--headers' + Display summary information from the section headers of the object + file. + + File segments may be relocated to nonstandard addresses, for + example by using the `-Ttext', `-Tdata', or `-Tbss' options to + `ld'. However, some object file formats, such as a.out, do not + store the starting address of the file segments. In those + situations, although `ld' relocates the sections correctly, using + `objdump -h' to list the file section headers cannot show the + correct addresses. Instead, it shows the usual addresses, which + are implicit for the target. + +`-H' +`--help' + Print a summary of the options to `objdump' and exit. + +`-i' +`--info' + Display a list showing all architectures and object formats + available for specification with `-b' or `-m'. + +`-j NAME' +`--section=NAME' + Display information only for section NAME. + +`-l' +`--line-numbers' + Label the display (using debugging information) with the filename + and source line numbers corresponding to the object code or relocs + shown. Only useful with `-d', `-D', or `-r'. + +`-m MACHINE' +`--architecture=MACHINE' + Specify the architecture to use when disassembling object files. + This can be useful when disassembling object files which do not + describe architecture information, such as S-records. You can + list the available architectures with the `-i' option. + + If the target is an ARM architecture then this switch has an + additional effect. It restricts the disassembly to only those + instructions supported by the architecture specified by MACHINE. + If it is necessary to use this switch because the input file does + not contain any architecture information, but it is also desired to + disassemble all the instructions use `-marm'. + +`-M OPTIONS' +`--disassembler-options=OPTIONS' + Pass target specific information to the disassembler. Only + supported on some targets. If it is necessary to specify more + than one disassembler option then multiple `-M' options can be + used or can be placed together into a comma separated list. + + If the target is an ARM architecture then this switch can be used + to select which register name set is used during disassembler. + Specifying `-M reg-names-std' (the default) will select the + register names as used in ARM's instruction set documentation, but + with register 13 called 'sp', register 14 called 'lr' and register + 15 called 'pc'. Specifying `-M reg-names-apcs' will select the + name set used by the ARM Procedure Call Standard, whilst + specifying `-M reg-names-raw' will just use `r' followed by the + register number. + + There are also two variants on the APCS register naming scheme + enabled by `-M reg-names-atpcs' and `-M reg-names-special-atpcs' + which use the ARM/Thumb Procedure Call Standard naming + conventions. (Either with the normal register names or the + special register names). + + This option can also be used for ARM architectures to force the + disassembler to interpret all instructions as Thumb instructions by + using the switch `--disassembler-options=force-thumb'. This can be + useful when attempting to disassemble thumb code produced by other + compilers. + + For the x86, some of the options duplicate functions of the `-m' + switch, but allow finer grained control. Multiple selections from + the following may be specified as a comma separated string. + `x86-64', `i386' and `i8086' select disassembly for the given + architecture. `intel' and `att' select between intel syntax mode + and AT&T syntax mode. `intel-mnemonic' and `att-mnemonic' select + between intel mnemonic mode and AT&T mnemonic mode. + `intel-mnemonic' implies `intel' and `att-mnemonic' implies `att'. + `addr64', `addr32', `addr16', `data32' and `data16' specify the + default address size and operand size. These four options will be + overridden if `x86-64', `i386' or `i8086' appear later in the + option string. Lastly, `suffix', when in AT&T mode, instructs the + disassembler to print a mnemonic suffix even when the suffix could + be inferred by the operands. + + For PowerPC, `booke' controls the disassembly of BookE + instructions. `32' and `64' select PowerPC and PowerPC64 + disassembly, respectively. `e300' selects disassembly for the + e300 family. `440' selects disassembly for the PowerPC 440. + `ppcps' selects disassembly for the paired single instructions of + the PPC750CL. + + For MIPS, this option controls the printing of instruction mnemonic + names and register names in disassembled instructions. Multiple + selections from the following may be specified as a comma separated + string, and invalid options are ignored: + + `no-aliases' + Print the 'raw' instruction mnemonic instead of some pseudo + instruction mnemonic. I.e., print 'daddu' or 'or' instead of + 'move', 'sll' instead of 'nop', etc. + + `gpr-names=ABI' + Print GPR (general-purpose register) names as appropriate for + the specified ABI. By default, GPR names are selected + according to the ABI of the binary being disassembled. + + `fpr-names=ABI' + Print FPR (floating-point register) names as appropriate for + the specified ABI. By default, FPR numbers are printed + rather than names. + + `cp0-names=ARCH' + Print CP0 (system control coprocessor; coprocessor 0) + register names as appropriate for the CPU or architecture + specified by ARCH. By default, CP0 register names are + selected according to the architecture and CPU of the binary + being disassembled. + + `hwr-names=ARCH' + Print HWR (hardware register, used by the `rdhwr' + instruction) names as appropriate for the CPU or architecture + specified by ARCH. By default, HWR names are selected + according to the architecture and CPU of the binary being + disassembled. + + `reg-names=ABI' + Print GPR and FPR names as appropriate for the selected ABI. + + `reg-names=ARCH' + Print CPU-specific register names (CP0 register and HWR names) + as appropriate for the selected CPU or architecture. + + For any of the options listed above, ABI or ARCH may be specified + as `numeric' to have numbers printed rather than names, for the + selected types of registers. You can list the available values of + ABI and ARCH using the `--help' option. + + For VAX, you can specify function entry addresses with `-M + entry:0xf00ba'. You can use this multiple times to properly + disassemble VAX binary files that don't contain symbol tables (like + ROM dumps). In these cases, the function entry mask would + otherwise be decoded as VAX instructions, which would probably + lead the rest of the function being wrongly disassembled. + +`-p' +`--private-headers' + Print information that is specific to the object file format. The + exact information printed depends upon the object file format. + For some object file formats, no additional information is printed. + +`-r' +`--reloc' + Print the relocation entries of the file. If used with `-d' or + `-D', the relocations are printed interspersed with the + disassembly. + +`-R' +`--dynamic-reloc' + Print the dynamic relocation entries of the file. This is only + meaningful for dynamic objects, such as certain types of shared + libraries. As for `-r', if used with `-d' or `-D', the + relocations are printed interspersed with the disassembly. + +`-s' +`--full-contents' + Display the full contents of any sections requested. By default + all non-empty sections are displayed. + +`-S' +`--source' + Display source code intermixed with disassembly, if possible. + Implies `-d'. + +`--prefix=PREFIX' + Specify PREFIX to add to the absolute paths when used with `-S'. + +`--prefix-strip=LEVEL' + Indicate how many initial directory names to strip off the + hardwired absolute paths. It has no effect without + `--prefix='PREFIX. + +`--show-raw-insn' + When disassembling instructions, print the instruction in hex as + well as in symbolic form. This is the default except when + `--prefix-addresses' is used. + +`--no-show-raw-insn' + When disassembling instructions, do not print the instruction + bytes. This is the default when `--prefix-addresses' is used. + +`--insn-width=WIDTH' + Display WIDTH bytes on a single line when disassembling + instructions. + +`-W[lLiaprmfFsoR]' +`--dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges]' + Displays the contents of the debug sections in the file, if any are + present. If one of the optional letters or words follows the + switch then only data found in those specific sections will be + dumped. + +`-G' +`--stabs' + Display the full contents of any sections requested. Display the + contents of the .stab and .stab.index and .stab.excl sections from + an ELF file. This is only useful on systems (such as Solaris 2.0) + in which `.stab' debugging symbol-table entries are carried in an + ELF section. In most other file formats, debugging symbol-table + entries are interleaved with linkage symbols, and are visible in + the `--syms' output. For more information on stabs symbols, see + *Note Stabs: (stabs.info)Top. + +`--start-address=ADDRESS' + Start displaying data at the specified address. This affects the + output of the `-d', `-r' and `-s' options. + +`--stop-address=ADDRESS' + Stop displaying data at the specified address. This affects the + output of the `-d', `-r' and `-s' options. + +`-t' +`--syms' + Print the symbol table entries of the file. This is similar to + the information provided by the `nm' program, although the display + format is different. The format of the output depends upon the + format of the file being dumped, but there are two main types. + One looks like this: + + [ 4](sec 3)(fl 0x00)(ty 0)(scl 3) (nx 1) 0x00000000 .bss + [ 6](sec 1)(fl 0x00)(ty 0)(scl 2) (nx 0) 0x00000000 fred + + where the number inside the square brackets is the number of the + entry in the symbol table, the SEC number is the section number, + the FL value are the symbol's flag bits, the TY number is the + symbol's type, the SCL number is the symbol's storage class and + the NX value is the number of auxilary entries associated with the + symbol. The last two fields are the symbol's value and its name. + + The other common output format, usually seen with ELF based files, + looks like this: + + 00000000 l d .bss 00000000 .bss + 00000000 g .text 00000000 fred + + Here the first number is the symbol's value (sometimes refered to + as its address). The next field is actually a set of characters + and spaces indicating the flag bits that are set on the symbol. + These characters are described below. Next is the section with + which the symbol is associated or _*ABS*_ if the section is + absolute (ie not connected with any section), or _*UND*_ if the + section is referenced in the file being dumped, but not defined + there. + + After the section name comes another field, a number, which for + common symbols is the alignment and for other symbol is the size. + Finally the symbol's name is displayed. + + The flag characters are divided into 7 groups as follows: + `l' + `g' + `u' + `!' + The symbol is a local (l), global (g), unique global (u), + neither global nor local (a space) or both global and local + (!). A symbol can be neither local or global for a variety + of reasons, e.g., because it is used for debugging, but it is + probably an indication of a bug if it is ever both local and + global. Unique global symbols are a GNU extension to the + standard set of ELF symbol bindings. For such a symbol the + dynamic linker will make sure that in the entire process + there is just one symbol with this name and type in use. + + `w' + The symbol is weak (w) or strong (a space). + + `C' + The symbol denotes a constructor (C) or an ordinary symbol (a + space). + + `W' + The symbol is a warning (W) or a normal symbol (a space). A + warning symbol's name is a message to be displayed if the + symbol following the warning symbol is ever referenced. + + `I' + + `i' + The symbol is an indirect reference to another symbol (I), a + function to be evaluated during reloc processing (i) or a + normal symbol (a space). + + `d' + `D' + The symbol is a debugging symbol (d) or a dynamic symbol (D) + or a normal symbol (a space). + + `F' + + `f' + + `O' + The symbol is the name of a function (F) or a file (f) or an + object (O) or just a normal symbol (a space). + +`-T' +`--dynamic-syms' + Print the dynamic symbol table entries of the file. This is only + meaningful for dynamic objects, such as certain types of shared + libraries. This is similar to the information provided by the `nm' + program when given the `-D' (`--dynamic') option. + +`--special-syms' + When displaying symbols include those which the target considers + to be special in some way and which would not normally be of + interest to the user. + +`-V' +`--version' + Print the version number of `objdump' and exit. + +`-x' +`--all-headers' + Display all available header information, including the symbol + table and relocation entries. Using `-x' is equivalent to + specifying all of `-a -f -h -p -r -t'. + +`-w' +`--wide' + Format some lines for output devices that have more than 80 + columns. Also do not truncate symbol names when they are + displayed. + +`-z' +`--disassemble-zeroes' + Normally the disassembly output will skip blocks of zeroes. This + option directs the disassembler to disassemble those blocks, just + like any other data. + + +File: binutils.info, Node: ranlib, Next: readelf, Prev: objdump, Up: Top + +5 ranlib +******** + + ranlib [`-vVt'] ARCHIVE + + `ranlib' generates an index to the contents of an archive and stores +it in the archive. The index lists each symbol defined by a member of +an archive that is a relocatable object file. + + You may use `nm -s' or `nm --print-armap' to list this index. + + An archive with such an index speeds up linking to the library and +allows routines in the library to call each other without regard to +their placement in the archive. + + The GNU `ranlib' program is another form of GNU `ar'; running +`ranlib' is completely equivalent to executing `ar -s'. *Note ar::. + +`-v' +`-V' +`--version' + Show the version number of `ranlib'. + +`-t' + Update the timestamp of the symbol map of an archive. + + +File: binutils.info, Node: size, Next: strings, Prev: readelf, Up: Top + +6 size +****** + + size [`-A'|`-B'|`--format='COMPATIBILITY] + [`--help'] + [`-d'|`-o'|`-x'|`--radix='NUMBER] + [`--common'] + [`-t'|`--totals'] + [`--target='BFDNAME] [`-V'|`--version'] + [OBJFILE...] + + The GNU `size' utility lists the section sizes--and the total +size--for each of the object or archive files OBJFILE in its argument +list. By default, one line of output is generated for each object file +or each module in an archive. + + OBJFILE... are the object files to be examined. If none are +specified, the file `a.out' will be used. + + The command line options have the following meanings: + +`-A' +`-B' +`--format=COMPATIBILITY' + Using one of these options, you can choose whether the output from + GNU `size' resembles output from System V `size' (using `-A', or + `--format=sysv'), or Berkeley `size' (using `-B', or + `--format=berkeley'). The default is the one-line format similar + to Berkeley's. + + Here is an example of the Berkeley (default) format of output from + `size': + $ size --format=Berkeley ranlib size + text data bss dec hex filename + 294880 81920 11592 388392 5ed28 ranlib + 294880 81920 11888 388688 5ee50 size + + This is the same data, but displayed closer to System V + conventions: + + $ size --format=SysV ranlib size + ranlib : + section size addr + .text 294880 8192 + .data 81920 303104 + .bss 11592 385024 + Total 388392 + + + size : + section size addr + .text 294880 8192 + .data 81920 303104 + .bss 11888 385024 + Total 388688 + +`--help' + Show a summary of acceptable arguments and options. + +`-d' +`-o' +`-x' +`--radix=NUMBER' + Using one of these options, you can control whether the size of + each section is given in decimal (`-d', or `--radix=10'); octal + (`-o', or `--radix=8'); or hexadecimal (`-x', or `--radix=16'). + In `--radix=NUMBER', only the three values (8, 10, 16) are + supported. The total size is always given in two radices; decimal + and hexadecimal for `-d' or `-x' output, or octal and hexadecimal + if you're using `-o'. + +`--common' + Print total size of common symbols in each file. When using + Berkeley format these are included in the bss size. + +`-t' +`--totals' + Show totals of all objects listed (Berkeley format listing mode + only). + +`--target=BFDNAME' + Specify that the object-code format for OBJFILE is BFDNAME. This + option may not be necessary; `size' can automatically recognize + many formats. *Note Target Selection::, for more information. + +`-V' +`--version' + Display the version number of `size'. + + +File: binutils.info, Node: strings, Next: strip, Prev: size, Up: Top + +7 strings +********* + + strings [`-afovV'] [`-'MIN-LEN] + [`-n' MIN-LEN] [`--bytes='MIN-LEN] + [`-t' RADIX] [`--radix='RADIX] + [`-e' ENCODING] [`--encoding='ENCODING] + [`-'] [`--all'] [`--print-file-name'] + [`-T' BFDNAME] [`--target='BFDNAME] + [`--help'] [`--version'] FILE... + + For each FILE given, GNU `strings' prints the printable character +sequences that are at least 4 characters long (or the number given with +the options below) and are followed by an unprintable character. By +default, it only prints the strings from the initialized and loaded +sections of object files; for other types of files, it prints the +strings from the whole file. + + `strings' is mainly useful for determining the contents of non-text +files. + +`-a' +`--all' +`-' + Do not scan only the initialized and loaded sections of object + files; scan the whole files. + +`-f' +`--print-file-name' + Print the name of the file before each string. + +`--help' + Print a summary of the program usage on the standard output and + exit. + +`-MIN-LEN' +`-n MIN-LEN' +`--bytes=MIN-LEN' + Print sequences of characters that are at least MIN-LEN characters + long, instead of the default 4. + +`-o' + Like `-t o'. Some other versions of `strings' have `-o' act like + `-t d' instead. Since we can not be compatible with both ways, we + simply chose one. + +`-t RADIX' +`--radix=RADIX' + Print the offset within the file before each string. The single + character argument specifies the radix of the offset--`o' for + octal, `x' for hexadecimal, or `d' for decimal. + +`-e ENCODING' +`--encoding=ENCODING' + Select the character encoding of the strings that are to be found. + Possible values for ENCODING are: `s' = single-7-bit-byte + characters (ASCII, ISO 8859, etc., default), `S' = + single-8-bit-byte characters, `b' = 16-bit bigendian, `l' = 16-bit + littleendian, `B' = 32-bit bigendian, `L' = 32-bit littleendian. + Useful for finding wide character strings. (`l' and `b' apply to, + for example, Unicode UTF-16/UCS-2 encodings). + +`-T BFDNAME' +`--target=BFDNAME' + Specify an object code format other than your system's default + format. *Note Target Selection::, for more information. + +`-v' +`-V' +`--version' + Print the program version number on the standard output and exit. + + +File: binutils.info, Node: strip, Next: c++filt, Prev: strings, Up: Top + +8 strip +******* + + strip [`-F' BFDNAME |`--target='BFDNAME] + [`-I' BFDNAME |`--input-target='BFDNAME] + [`-O' BFDNAME |`--output-target='BFDNAME] + [`-s'|`--strip-all'] + [`-S'|`-g'|`-d'|`--strip-debug'] + [`-K' SYMBOLNAME |`--keep-symbol='SYMBOLNAME] + [`-N' SYMBOLNAME |`--strip-symbol='SYMBOLNAME] + [`-w'|`--wildcard'] + [`-x'|`--discard-all'] [`-X' |`--discard-locals'] + [`-R' SECTIONNAME |`--remove-section='SECTIONNAME] + [`-o' FILE] [`-p'|`--preserve-dates'] + [`--keep-file-symbols'] + [`--only-keep-debug'] + [`-v' |`--verbose'] [`-V'|`--version'] + [`--help'] [`--info'] + OBJFILE... + + GNU `strip' discards all symbols from object files OBJFILE. The +list of object files may include archives. At least one object file +must be given. + + `strip' modifies the files named in its argument, rather than +writing modified copies under different names. + +`-F BFDNAME' +`--target=BFDNAME' + Treat the original OBJFILE as a file with the object code format + BFDNAME, and rewrite it in the same format. *Note Target + Selection::, for more information. + +`--help' + Show a summary of the options to `strip' and exit. + +`--info' + Display a list showing all architectures and object formats + available. + +`-I BFDNAME' +`--input-target=BFDNAME' + Treat the original OBJFILE as a file with the object code format + BFDNAME. *Note Target Selection::, for more information. + +`-O BFDNAME' +`--output-target=BFDNAME' + Replace OBJFILE with a file in the output format BFDNAME. *Note + Target Selection::, for more information. + +`-R SECTIONNAME' +`--remove-section=SECTIONNAME' + Remove any section named SECTIONNAME from the output file. This + option may be given more than once. Note that using this option + inappropriately may make the output file unusable. + +`-s' +`--strip-all' + Remove all symbols. + +`-g' +`-S' +`-d' +`--strip-debug' + Remove debugging symbols only. + +`--strip-unneeded' + Remove all symbols that are not needed for relocation processing. + +`-K SYMBOLNAME' +`--keep-symbol=SYMBOLNAME' + When stripping symbols, keep symbol SYMBOLNAME even if it would + normally be stripped. This option may be given more than once. + +`-N SYMBOLNAME' +`--strip-symbol=SYMBOLNAME' + Remove symbol SYMBOLNAME from the source file. This option may be + given more than once, and may be combined with strip options other + than `-K'. + +`-o FILE' + Put the stripped output in FILE, rather than replacing the + existing file. When this argument is used, only one OBJFILE + argument may be specified. + +`-p' +`--preserve-dates' + Preserve the access and modification dates of the file. + +`-w' +`--wildcard' + Permit regular expressions in SYMBOLNAMEs used in other command + line options. The question mark (?), asterisk (*), backslash (\) + and square brackets ([]) operators can be used anywhere in the + symbol name. If the first character of the symbol name is the + exclamation point (!) then the sense of the switch is reversed for + that symbol. For example: + + -w -K !foo -K fo* + + would cause strip to only keep symbols that start with the letters + "fo", but to discard the symbol "foo". + +`-x' +`--discard-all' + Remove non-global symbols. + +`-X' +`--discard-locals' + Remove compiler-generated local symbols. (These usually start + with `L' or `.'.) + +`--keep-file-symbols' + When stripping a file, perhaps with `--strip-debug' or + `--strip-unneeded', retain any symbols specifying source file + names, which would otherwise get stripped. + +`--only-keep-debug' + Strip a file, removing contents of any sections that would not be + stripped by `--strip-debug' and leaving the debugging sections + intact. In ELF files, this preserves all note sections in the + output. + + The intention is that this option will be used in conjunction with + `--add-gnu-debuglink' to create a two part executable. One a + stripped binary which will occupy less space in RAM and in a + distribution and the second a debugging information file which is + only needed if debugging abilities are required. The suggested + procedure to create these files is as follows: + + 1. Link the executable as normal. Assuming that is is called + `foo' then... + + 2. Run `objcopy --only-keep-debug foo foo.dbg' to create a file + containing the debugging info. + + 3. Run `objcopy --strip-debug foo' to create a stripped + executable. + + 4. Run `objcopy --add-gnu-debuglink=foo.dbg foo' to add a link + to the debugging info into the stripped executable. + + Note--the choice of `.dbg' as an extension for the debug info file + is arbitrary. Also the `--only-keep-debug' step is optional. You + could instead do this: + + 1. Link the executable as normal. + + 2. Copy `foo' to `foo.full' + + 3. Run `strip --strip-debug foo' + + 4. Run `objcopy --add-gnu-debuglink=foo.full foo' + + i.e., the file pointed to by the `--add-gnu-debuglink' can be the + full executable. It does not have to be a file created by the + `--only-keep-debug' switch. + + Note--this switch is only intended for use on fully linked files. + It does not make sense to use it on object files where the + debugging information may be incomplete. Besides the + gnu_debuglink feature currently only supports the presence of one + filename containing debugging information, not multiple filenames + on a one-per-object-file basis. + +`-V' +`--version' + Show the version number for `strip'. + +`-v' +`--verbose' + Verbose output: list all object files modified. In the case of + archives, `strip -v' lists all members of the archive. + + +File: binutils.info, Node: c++filt, Next: addr2line, Prev: strip, Up: Top + +9 c++filt +********* + + c++filt [`-_'|`--strip-underscores'] + [`-n'|`--no-strip-underscores'] + [`-p'|`--no-params'] + [`-t'|`--types'] + [`-i'|`--no-verbose'] + [`-s' FORMAT|`--format='FORMAT] + [`--help'] [`--version'] [SYMBOL...] + + The C++ and Java languages provide function overloading, which means +that you can write many functions with the same name, providing that +each function takes parameters of different types. In order to be able +to distinguish these similarly named functions C++ and Java encode them +into a low-level assembler name which uniquely identifies each +different version. This process is known as "mangling". The `c++filt' +(1) program does the inverse mapping: it decodes ("demangles") low-level +names into user-level names so that they can be read. + + Every alphanumeric word (consisting of letters, digits, underscores, +dollars, or periods) seen in the input is a potential mangled name. If +the name decodes into a C++ name, the C++ name replaces the low-level +name in the output, otherwise the original word is output. In this way +you can pass an entire assembler source file, containing mangled names, +through `c++filt' and see the same source file containing demangled +names. + + You can also use `c++filt' to decipher individual symbols by passing +them on the command line: + + c++filt SYMBOL + + If no SYMBOL arguments are given, `c++filt' reads symbol names from +the standard input instead. All the results are printed on the +standard output. The difference between reading names from the command +line versus reading names from the standard input is that command line +arguments are expected to be just mangled names and no checking is +performed to separate them from surrounding text. Thus for example: + + c++filt -n _Z1fv + + will work and demangle the name to "f()" whereas: + + c++filt -n _Z1fv, + + will not work. (Note the extra comma at the end of the mangled name +which makes it invalid). This command however will work: + + echo _Z1fv, | c++filt -n + + and will display "f(),", i.e., the demangled name followed by a +trailing comma. This behaviour is because when the names are read from +the standard input it is expected that they might be part of an +assembler source file where there might be extra, extraneous characters +trailing after a mangled name. For example: + + .type _Z1fv, @function + +`-_' +`--strip-underscores' + On some systems, both the C and C++ compilers put an underscore in + front of every name. For example, the C name `foo' gets the + low-level name `_foo'. This option removes the initial + underscore. Whether `c++filt' removes the underscore by default + is target dependent. + +`-n' +`--no-strip-underscores' + Do not remove the initial underscore. + +`-p' +`--no-params' + When demangling the name of a function, do not display the types of + the function's parameters. + +`-t' +`--types' + Attempt to demangle types as well as function names. This is + disabled by default since mangled types are normally only used + internally in the compiler, and they can be confused with + non-mangled names. For example, a function called "a" treated as + a mangled type name would be demangled to "signed char". + +`-i' +`--no-verbose' + Do not include implementation details (if any) in the demangled + output. + +`-s FORMAT' +`--format=FORMAT' + `c++filt' can decode various methods of mangling, used by + different compilers. The argument to this option selects which + method it uses: + + `auto' + Automatic selection based on executable (the default method) + + `gnu' + the one used by the GNU C++ compiler (g++) + + `lucid' + the one used by the Lucid compiler (lcc) + + `arm' + the one specified by the C++ Annotated Reference Manual + + `hp' + the one used by the HP compiler (aCC) + + `edg' + the one used by the EDG compiler + + `gnu-v3' + the one used by the GNU C++ compiler (g++) with the V3 ABI. + + `java' + the one used by the GNU Java compiler (gcj) + + `gnat' + the one used by the GNU Ada compiler (GNAT). + +`--help' + Print a summary of the options to `c++filt' and exit. + +`--version' + Print the version number of `c++filt' and exit. + + _Warning:_ `c++filt' is a new utility, and the details of its user + interface are subject to change in future releases. In particular, + a command-line option may be required in the future to decode a + name passed as an argument on the command line; in other words, + + c++filt SYMBOL + + may in a future release become + + c++filt OPTION SYMBOL + + ---------- Footnotes ---------- + + (1) MS-DOS does not allow `+' characters in file names, so on MS-DOS +this program is named `CXXFILT'. + + +File: binutils.info, Node: addr2line, Next: nlmconv, Prev: c++filt, Up: Top + +10 addr2line +************ + + addr2line [`-b' BFDNAME|`--target='BFDNAME] + [`-C'|`--demangle'[=STYLE]] + [`-e' FILENAME|`--exe='FILENAME] + [`-f'|`--functions'] [`-s'|`--basename'] + [`-i'|`--inlines'] + [`-j'|`--section='NAME] + [`-H'|`--help'] [`-V'|`--version'] + [addr addr ...] + + `addr2line' translates addresses into file names and line numbers. +Given an address in an executable or an offset in a section of a +relocatable object, it uses the debugging information to figure out +which file name and line number are associated with it. + + The executable or relocatable object to use is specified with the +`-e' option. The default is the file `a.out'. The section in the +relocatable object to use is specified with the `-j' option. + + `addr2line' has two modes of operation. + + In the first, hexadecimal addresses are specified on the command +line, and `addr2line' displays the file name and line number for each +address. + + In the second, `addr2line' reads hexadecimal addresses from standard +input, and prints the file name and line number for each address on +standard output. In this mode, `addr2line' may be used in a pipe to +convert dynamically chosen addresses. + + The format of the output is `FILENAME:LINENO'. The file name and +line number for each address is printed on a separate line. If the +`-f' option is used, then each `FILENAME:LINENO' line is preceded by a +`FUNCTIONNAME' line which is the name of the function containing the +address. + + If the file name or function name can not be determined, `addr2line' +will print two question marks in their place. If the line number can +not be determined, `addr2line' will print 0. + + The long and short forms of options, shown here as alternatives, are +equivalent. + +`-b BFDNAME' +`--target=BFDNAME' + Specify that the object-code format for the object files is + BFDNAME. + +`-C' +`--demangle[=STYLE]' + Decode ("demangle") low-level symbol names into user-level names. + Besides removing any initial underscore prepended by the system, + this makes C++ function names readable. Different compilers have + different mangling styles. The optional demangling style argument + can be used to choose an appropriate demangling style for your + compiler. *Note c++filt::, for more information on demangling. + +`-e FILENAME' +`--exe=FILENAME' + Specify the name of the executable for which addresses should be + translated. The default file is `a.out'. + +`-f' +`--functions' + Display function names as well as file and line number information. + +`-s' +`--basenames' + Display only the base of each file name. + +`-i' +`--inlines' + If the address belongs to a function that was inlined, the source + information for all enclosing scopes back to the first non-inlined + function will also be printed. For example, if `main' inlines + `callee1' which inlines `callee2', and address is from `callee2', + the source information for `callee1' and `main' will also be + printed. + +`-j' +`--section' + Read offsets relative to the specified section instead of absolute + addresses. + + +File: binutils.info, Node: nlmconv, Next: windres, Prev: addr2line, Up: Top + +11 nlmconv +********** + +`nlmconv' converts a relocatable object file into a NetWare Loadable +Module. + + _Warning:_ `nlmconv' is not always built as part of the binary + utilities, since it is only useful for NLM targets. + + nlmconv [`-I' BFDNAME|`--input-target='BFDNAME] + [`-O' BFDNAME|`--output-target='BFDNAME] + [`-T' HEADERFILE|`--header-file='HEADERFILE] + [`-d'|`--debug'] [`-l' LINKER|`--linker='LINKER] + [`-h'|`--help'] [`-V'|`--version'] + INFILE OUTFILE + + `nlmconv' converts the relocatable `i386' object file INFILE into +the NetWare Loadable Module OUTFILE, optionally reading HEADERFILE for +NLM header information. For instructions on writing the NLM command +file language used in header files, see the `linkers' section, +`NLMLINK' in particular, of the `NLM Development and Tools Overview', +which is part of the NLM Software Developer's Kit ("NLM SDK"), +available from Novell, Inc. `nlmconv' uses the GNU Binary File +Descriptor library to read INFILE; see *Note BFD: (ld.info)BFD, for +more information. + + `nlmconv' can perform a link step. In other words, you can list +more than one object file for input if you list them in the definitions +file (rather than simply specifying one input file on the command line). +In this case, `nlmconv' calls the linker for you. + +`-I BFDNAME' +`--input-target=BFDNAME' + Object format of the input file. `nlmconv' can usually determine + the format of a given file (so no default is necessary). *Note + Target Selection::, for more information. + +`-O BFDNAME' +`--output-target=BFDNAME' + Object format of the output file. `nlmconv' infers the output + format based on the input format, e.g. for a `i386' input file the + output format is `nlm32-i386'. *Note Target Selection::, for more + information. + +`-T HEADERFILE' +`--header-file=HEADERFILE' + Reads HEADERFILE for NLM header information. For instructions on + writing the NLM command file language used in header files, see + see the `linkers' section, of the `NLM Development and Tools + Overview', which is part of the NLM Software Developer's Kit, + available from Novell, Inc. + +`-d' +`--debug' + Displays (on standard error) the linker command line used by + `nlmconv'. + +`-l LINKER' +`--linker=LINKER' + Use LINKER for any linking. LINKER can be an absolute or a + relative pathname. + +`-h' +`--help' + Prints a usage summary. + +`-V' +`--version' + Prints the version number for `nlmconv'. + + +File: binutils.info, Node: windmc, Next: dlltool, Prev: windres, Up: Top + +12 windmc +********* + +`windmc' may be used to generator Windows message resources. + + _Warning:_ `windmc' is not always built as part of the binary + utilities, since it is only useful for Windows targets. + + windmc [options] input-file + + `windmc' reads message definitions from an input file (.mc) and +translate them into a set of output files. The output files may be of +four kinds: + +`h' + A C header file containing the message definitions. + +`rc' + A resource file compilable by the `windres' tool. + +`bin' + One or more binary files containing the resource data for a + specific message language. + +`dbg' + A C include file that maps message id's to their symbolic name. + + The exact description of these different formats is available in +documentation from Microsoft. + + When `windmc' converts from the `mc' format to the `bin' format, +`rc', `h', and optional `dbg' it is acting like the Windows Message +Compiler. + +`-a' +`--ascii_in' + Specifies that the input file specified is ANSI. This is the + default behaviour. + +`-A' +`--ascii_out' + Specifies that messages in the output `bin' files should be in ANSI + format. + +`-b' +`--binprefix' + Specifies that `bin' filenames should have to be prefixed by the + basename of the source file. + +`-c' +`--customflag' + Sets the customer bit in all message id's. + +`-C CODEPAGE' +`--codepage_in CODEPAGE' + Sets the default codepage to be used to convert input file to + UTF16. The default is ocdepage 1252. + +`-d' +`--decimal_values' + Outputs the constants in the header file in decimal. Default is + using hexadecimal output. + +`-e EXT' +`--extension EXT' + The extension for the header file. The default is .h extension. + +`-F TARGET' +`--target TARGET' + Specify the BFD format to use for a bin file as output. This is a + BFD target name; you can use the `--help' option to see a list of + supported targets. Normally `windmc' will use the default format, + which is the first one listed by the `--help' option. *Note + Target Selection::. + +`-h PATH' +`--headerdir PATH' + The target directory of the generated header file. The default is + the current directory. + +`-H' +`--help' + Displays a list of command line options and then exits. + +`-m CHARACTERS' +`--maxlength CHARACTERS' + Instructs `windmc' to generate a warning if the length of any + message exceeds the number specified. + +`-n' +`--nullterminate' + Terminate message text in `bin' files by zero. By default they are + terminated by CR/LF. + +`-o' +`--hresult_use' + Not yet implemented. Instructs `windmc' to generate an OLE2 header + file, using HRESULT definitions. Status codes are used if the flag + is not specified. + +`-O CODEPAGE' +`--codepage_out CODEPAGE' + Sets the default codepage to be used to output text files. The + default is ocdepage 1252. + +`-r PATH' +`--rcdir PATH' + The target directory for the generated `rc' script and the + generated `bin' files that the resource compiler script includes. + The default is the current directory. + +`-u' +`--unicode_in' + Specifies that the input file is UTF16. + +`-U' +`--unicode_out' + Specifies that messages in the output `bin' file should be in UTF16 + format. This is the default behaviour. + +`-v' + +`--verbose' + Enable verbose mode. + +`-V' + +`--version' + Prints the version number for `windmc'. + +`-x PATH' +`--xdgb PATH' + The path of the `dbg' C include file that maps message id's to the + symbolic name. No such file is generated without specifying the + switch. + + +File: binutils.info, Node: windres, Next: windmc, Prev: nlmconv, Up: Top + +13 windres +********** + +`windres' may be used to manipulate Windows resources. + + _Warning:_ `windres' is not always built as part of the binary + utilities, since it is only useful for Windows targets. + + windres [options] [input-file] [output-file] + + `windres' reads resources from an input file and copies them into an +output file. Either file may be in one of three formats: + +`rc' + A text format read by the Resource Compiler. + +`res' + A binary format generated by the Resource Compiler. + +`coff' + A COFF object or executable. + + The exact description of these different formats is available in +documentation from Microsoft. + + When `windres' converts from the `rc' format to the `res' format, it +is acting like the Windows Resource Compiler. When `windres' converts +from the `res' format to the `coff' format, it is acting like the +Windows `CVTRES' program. + + When `windres' generates an `rc' file, the output is similar but not +identical to the format expected for the input. When an input `rc' +file refers to an external filename, an output `rc' file will instead +include the file contents. + + If the input or output format is not specified, `windres' will guess +based on the file name, or, for the input file, the file contents. A +file with an extension of `.rc' will be treated as an `rc' file, a file +with an extension of `.res' will be treated as a `res' file, and a file +with an extension of `.o' or `.exe' will be treated as a `coff' file. + + If no output file is specified, `windres' will print the resources +in `rc' format to standard output. + + The normal use is for you to write an `rc' file, use `windres' to +convert it to a COFF object file, and then link the COFF file into your +application. This will make the resources described in the `rc' file +available to Windows. + +`-i FILENAME' +`--input FILENAME' + The name of the input file. If this option is not used, then + `windres' will use the first non-option argument as the input file + name. If there are no non-option arguments, then `windres' will + read from standard input. `windres' can not read a COFF file from + standard input. + +`-o FILENAME' +`--output FILENAME' + The name of the output file. If this option is not used, then + `windres' will use the first non-option argument, after any used + for the input file name, as the output file name. If there is no + non-option argument, then `windres' will write to standard output. + `windres' can not write a COFF file to standard output. Note, for + compatibility with `rc' the option `-fo' is also accepted, but its + use is not recommended. + +`-J FORMAT' +`--input-format FORMAT' + The input format to read. FORMAT may be `res', `rc', or `coff'. + If no input format is specified, `windres' will guess, as + described above. + +`-O FORMAT' +`--output-format FORMAT' + The output format to generate. FORMAT may be `res', `rc', or + `coff'. If no output format is specified, `windres' will guess, + as described above. + +`-F TARGET' +`--target TARGET' + Specify the BFD format to use for a COFF file as input or output. + This is a BFD target name; you can use the `--help' option to see + a list of supported targets. Normally `windres' will use the + default format, which is the first one listed by the `--help' + option. *Note Target Selection::. + +`--preprocessor PROGRAM' + When `windres' reads an `rc' file, it runs it through the C + preprocessor first. This option may be used to specify the + preprocessor to use, including any leading arguments. The default + preprocessor argument is `gcc -E -xc-header -DRC_INVOKED'. + +`-I DIRECTORY' +`--include-dir DIRECTORY' + Specify an include directory to use when reading an `rc' file. + `windres' will pass this to the preprocessor as an `-I' option. + `windres' will also search this directory when looking for files + named in the `rc' file. If the argument passed to this command + matches any of the supported FORMATS (as described in the `-J' + option), it will issue a deprecation warning, and behave just like + the `-J' option. New programs should not use this behaviour. If a + directory happens to match a FORMAT, simple prefix it with `./' to + disable the backward compatibility. + +`-D TARGET' +`--define SYM[=VAL]' + Specify a `-D' option to pass to the preprocessor when reading an + `rc' file. + +`-U TARGET' +`--undefine SYM' + Specify a `-U' option to pass to the preprocessor when reading an + `rc' file. + +`-r' + Ignored for compatibility with rc. + +`-v' + Enable verbose mode. This tells you what the preprocessor is if + you didn't specify one. + +`-c VAL' + +`--codepage VAL' + Specify the default codepage to use when reading an `rc' file. + VAL should be a hexadecimal prefixed by `0x' or decimal codepage + code. The valid range is from zero up to 0xffff, but the validity + of the codepage is host and configuration dependent. + +`-l VAL' + +`--language VAL' + Specify the default language to use when reading an `rc' file. + VAL should be a hexadecimal language code. The low eight bits are + the language, and the high eight bits are the sublanguage. + +`--use-temp-file' + Use a temporary file to instead of using popen to read the output + of the preprocessor. Use this option if the popen implementation + is buggy on the host (eg., certain non-English language versions + of Windows 95 and Windows 98 are known to have buggy popen where + the output will instead go the console). + +`--no-use-temp-file' + Use popen, not a temporary file, to read the output of the + preprocessor. This is the default behaviour. + +`-h' + +`--help' + Prints a usage summary. + +`-V' + +`--version' + Prints the version number for `windres'. + +`--yydebug' + If `windres' is compiled with `YYDEBUG' defined as `1', this will + turn on parser debugging. + + +File: binutils.info, Node: dlltool, Next: Common Options, Prev: windmc, Up: Top + +14 dlltool +********** + +`dlltool' is used to create the files needed to create dynamic link +libraries (DLLs) on systems which understand PE format image files such +as Windows. A DLL contains an export table which contains information +that the runtime loader needs to resolve references from a referencing +program. + + The export table is generated by this program by reading in a `.def' +file or scanning the `.a' and `.o' files which will be in the DLL. A +`.o' file can contain information in special `.drectve' sections with +export information. + + _Note:_ `dlltool' is not always built as part of the binary + utilities, since it is only useful for those targets which support + DLLs. + + dlltool [`-d'|`--input-def' DEF-FILE-NAME] + [`-b'|`--base-file' BASE-FILE-NAME] + [`-e'|`--output-exp' EXPORTS-FILE-NAME] + [`-z'|`--output-def' DEF-FILE-NAME] + [`-l'|`--output-lib' LIBRARY-FILE-NAME] + [`-y'|`--output-delaylib' LIBRARY-FILE-NAME] + [`--export-all-symbols'] [`--no-export-all-symbols'] + [`--exclude-symbols' LIST] + [`--no-default-excludes'] + [`-S'|`--as' PATH-TO-ASSEMBLER] [`-f'|`--as-flags' OPTIONS] + [`-D'|`--dllname' NAME] [`-m'|`--machine' MACHINE] + [`-a'|`--add-indirect'] + [`-U'|`--add-underscore'] [`--add-stdcall-underscore'] + [`-k'|`--kill-at'] [`-A'|`--add-stdcall-alias'] + [`-p'|`--ext-prefix-alias' PREFIX] + [`-x'|`--no-idata4'] [`-c'|`--no-idata5'] + [`--use-nul-prefixed-import-tables'] + [`-I'|`--identify' LIBRARY-FILE-NAME] [`--identify-strict'] + [`-i'|`--interwork'] + [`-n'|`--nodelete'] [`-t'|`--temp-prefix' PREFIX] + [`-v'|`--verbose'] + [`-h'|`--help'] [`-V'|`--version'] + [object-file ...] + + `dlltool' reads its inputs, which can come from the `-d' and `-b' +options as well as object files specified on the command line. It then +processes these inputs and if the `-e' option has been specified it +creates a exports file. If the `-l' option has been specified it +creates a library file and if the `-z' option has been specified it +creates a def file. Any or all of the `-e', `-l' and `-z' options can +be present in one invocation of dlltool. + + When creating a DLL, along with the source for the DLL, it is +necessary to have three other files. `dlltool' can help with the +creation of these files. + + The first file is a `.def' file which specifies which functions are +exported from the DLL, which functions the DLL imports, and so on. This +is a text file and can be created by hand, or `dlltool' can be used to +create it using the `-z' option. In this case `dlltool' will scan the +object files specified on its command line looking for those functions +which have been specially marked as being exported and put entries for +them in the `.def' file it creates. + + In order to mark a function as being exported from a DLL, it needs to +have an `-export:<name_of_function>' entry in the `.drectve' section of +the object file. This can be done in C by using the asm() operator: + + asm (".section .drectve"); + asm (".ascii \"-export:my_func\""); + + int my_func (void) { ... } + + The second file needed for DLL creation is an exports file. This +file is linked with the object files that make up the body of the DLL +and it handles the interface between the DLL and the outside world. +This is a binary file and it can be created by giving the `-e' option to +`dlltool' when it is creating or reading in a `.def' file. + + The third file needed for DLL creation is the library file that +programs will link with in order to access the functions in the DLL (an +`import library'). This file can be created by giving the `-l' option +to dlltool when it is creating or reading in a `.def' file. + + If the `-y' option is specified, dlltool generates a delay-import +library that can be used instead of the normal import library to allow +a program to link to the dll only as soon as an imported function is +called for the first time. The resulting executable will need to be +linked to the static delayimp library containing __delayLoadHelper2(), +which in turn will import LoadLibraryA and GetProcAddress from kernel32. + + `dlltool' builds the library file by hand, but it builds the exports +file by creating temporary files containing assembler statements and +then assembling these. The `-S' command line option can be used to +specify the path to the assembler that dlltool will use, and the `-f' +option can be used to pass specific flags to that assembler. The `-n' +can be used to prevent dlltool from deleting these temporary assembler +files when it is done, and if `-n' is specified twice then this will +prevent dlltool from deleting the temporary object files it used to +build the library. + + Here is an example of creating a DLL from a source file `dll.c' and +also creating a program (from an object file called `program.o') that +uses that DLL: + + gcc -c dll.c + dlltool -e exports.o -l dll.lib dll.o + gcc dll.o exports.o -o dll.dll + gcc program.o dll.lib -o program + + `dlltool' may also be used to query an existing import library to +determine the name of the DLL to which it is associated. See the +description of the `-I' or `--identify' option. + + The command line options have the following meanings: + +`-d FILENAME' +`--input-def FILENAME' + Specifies the name of a `.def' file to be read in and processed. + +`-b FILENAME' +`--base-file FILENAME' + Specifies the name of a base file to be read in and processed. The + contents of this file will be added to the relocation section in + the exports file generated by dlltool. + +`-e FILENAME' +`--output-exp FILENAME' + Specifies the name of the export file to be created by dlltool. + +`-z FILENAME' +`--output-def FILENAME' + Specifies the name of the `.def' file to be created by dlltool. + +`-l FILENAME' +`--output-lib FILENAME' + Specifies the name of the library file to be created by dlltool. + +`-y FILENAME' +`--output-delaylib FILENAME' + Specifies the name of the delay-import library file to be created + by dlltool. + +`--export-all-symbols' + Treat all global and weak defined symbols found in the input object + files as symbols to be exported. There is a small list of symbols + which are not exported by default; see the `--no-default-excludes' + option. You may add to the list of symbols to not export by using + the `--exclude-symbols' option. + +`--no-export-all-symbols' + Only export symbols explicitly listed in an input `.def' file or in + `.drectve' sections in the input object files. This is the default + behaviour. The `.drectve' sections are created by `dllexport' + attributes in the source code. + +`--exclude-symbols LIST' + Do not export the symbols in LIST. This is a list of symbol names + separated by comma or colon characters. The symbol names should + not contain a leading underscore. This is only meaningful when + `--export-all-symbols' is used. + +`--no-default-excludes' + When `--export-all-symbols' is used, it will by default avoid + exporting certain special symbols. The current list of symbols to + avoid exporting is `DllMain@12', `DllEntryPoint@0', `impure_ptr'. + You may use the `--no-default-excludes' option to go ahead and + export these special symbols. This is only meaningful when + `--export-all-symbols' is used. + +`-S PATH' +`--as PATH' + Specifies the path, including the filename, of the assembler to be + used to create the exports file. + +`-f OPTIONS' +`--as-flags OPTIONS' + Specifies any specific command line options to be passed to the + assembler when building the exports file. This option will work + even if the `-S' option is not used. This option only takes one + argument, and if it occurs more than once on the command line, + then later occurrences will override earlier occurrences. So if + it is necessary to pass multiple options to the assembler they + should be enclosed in double quotes. + +`-D NAME' +`--dll-name NAME' + Specifies the name to be stored in the `.def' file as the name of + the DLL when the `-e' option is used. If this option is not + present, then the filename given to the `-e' option will be used + as the name of the DLL. + +`-m MACHINE' +`-machine MACHINE' + Specifies the type of machine for which the library file should be + built. `dlltool' has a built in default type, depending upon how + it was created, but this option can be used to override that. + This is normally only useful when creating DLLs for an ARM + processor, when the contents of the DLL are actually encode using + Thumb instructions. + +`-a' +`--add-indirect' + Specifies that when `dlltool' is creating the exports file it + should add a section which allows the exported functions to be + referenced without using the import library. Whatever the hell + that means! + +`-U' +`--add-underscore' + Specifies that when `dlltool' is creating the exports file it + should prepend an underscore to the names of _all_ exported + symbols. + +`--add-stdcall-underscore' + Specifies that when `dlltool' is creating the exports file it + should prepend an underscore to the names of exported _stdcall_ + functions. Variable names and non-stdcall function names are not + modified. This option is useful when creating GNU-compatible + import libs for third party DLLs that were built with MS-Windows + tools. + +`-k' +`--kill-at' + Specifies that when `dlltool' is creating the exports file it + should not append the string `@ <number>'. These numbers are + called ordinal numbers and they represent another way of accessing + the function in a DLL, other than by name. + +`-A' +`--add-stdcall-alias' + Specifies that when `dlltool' is creating the exports file it + should add aliases for stdcall symbols without `@ <number>' in + addition to the symbols with `@ <number>'. + +`-p' +`--ext-prefix-alias PREFIX' + Causes `dlltool' to create external aliases for all DLL imports + with the specified prefix. The aliases are created for both + external and import symbols with no leading underscore. + +`-x' +`--no-idata4' + Specifies that when `dlltool' is creating the exports and library + files it should omit the `.idata4' section. This is for + compatibility with certain operating systems. + +`--use-nul-prefixed-import-tables' + Specifies that when `dlltool' is creating the exports and library + files it should prefix the `.idata4' and `.idata5' by zero an + element. This emulates old gnu import library generation of + `dlltool'. By default this option is turned off. + +`-c' +`--no-idata5' + Specifies that when `dlltool' is creating the exports and library + files it should omit the `.idata5' section. This is for + compatibility with certain operating systems. + +`-I FILENAME' +`--identify FILENAME' + Specifies that `dlltool' should inspect the import library + indicated by FILENAME and report, on `stdout', the name(s) of the + associated DLL(s). This can be performed in addition to any other + operations indicated by the other options and arguments. + `dlltool' fails if the import library does not exist or is not + actually an import library. See also `--identify-strict'. + +`--identify-strict' + Modifies the behavior of the `--identify' option, such that an + error is reported if FILENAME is associated with more than one DLL. + +`-i' +`--interwork' + Specifies that `dlltool' should mark the objects in the library + file and exports file that it produces as supporting interworking + between ARM and Thumb code. + +`-n' +`--nodelete' + Makes `dlltool' preserve the temporary assembler files it used to + create the exports file. If this option is repeated then dlltool + will also preserve the temporary object files it uses to create + the library file. + +`-t PREFIX' +`--temp-prefix PREFIX' + Makes `dlltool' use PREFIX when constructing the names of + temporary assembler and object files. By default, the temp file + prefix is generated from the pid. + +`-v' +`--verbose' + Make dlltool describe what it is doing. + +`-h' +`--help' + Displays a list of command line options and then exits. + +`-V' +`--version' + Displays dlltool's version number and then exits. + + +* Menu: + +* def file format:: The format of the dlltool `.def' file + + +File: binutils.info, Node: def file format, Up: dlltool + +14.1 The format of the `dlltool' `.def' file +============================================ + +A `.def' file contains any number of the following commands: + +`NAME' NAME `[ ,' BASE `]' + The result is going to be named NAME`.exe'. + +`LIBRARY' NAME `[ ,' BASE `]' + The result is going to be named NAME`.dll'. + +`EXPORTS ( ( (' NAME1 `[ = ' NAME2 `] ) | ( ' NAME1 `=' MODULE-NAME `.' EXTERNAL-NAME `) )' + +`[' INTEGER `] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *' + Declares NAME1 as an exported symbol from the DLL, with optional + ordinal number INTEGER, or declares NAME1 as an alias (forward) of + the function EXTERNAL-NAME in the DLL MODULE-NAME. + +`IMPORTS ( (' INTERNAL-NAME `=' MODULE-NAME `.' INTEGER `) | [' INTERNAL-NAME `= ]' MODULE-NAME `.' EXTERNAL-NAME `) ) *' + Declares that EXTERNAL-NAME or the exported function whose ordinal + number is INTEGER is to be imported from the file MODULE-NAME. If + INTERNAL-NAME is specified then this is the name that the imported + function will be referred to in the body of the DLL. + +`DESCRIPTION' STRING + Puts STRING into the output `.exp' file in the `.rdata' section. + +`STACKSIZE' NUMBER-RESERVE `[, ' NUMBER-COMMIT `]' + +`HEAPSIZE' NUMBER-RESERVE `[, ' NUMBER-COMMIT `]' + Generates `--stack' or `--heap' NUMBER-RESERVE,NUMBER-COMMIT in + the output `.drectve' section. The linker will see this and act + upon it. + +`CODE' ATTR `+' + +`DATA' ATTR `+' + +`SECTIONS (' SECTION-NAME ATTR` + ) *' + Generates `--attr' SECTION-NAME ATTR in the output `.drectve' + section, where ATTR is one of `READ', `WRITE', `EXECUTE' or + `SHARED'. The linker will see this and act upon it. + + + +File: binutils.info, Node: readelf, Next: size, Prev: ranlib, Up: Top + +15 readelf +********** + + readelf [`-a'|`--all'] + [`-h'|`--file-header'] + [`-l'|`--program-headers'|`--segments'] + [`-S'|`--section-headers'|`--sections'] + [`-g'|`--section-groups'] + [`-t'|`--section-details'] + [`-e'|`--headers'] + [`-s'|`--syms'|`--symbols'] + [`-n'|`--notes'] + [`-r'|`--relocs'] + [`-u'|`--unwind'] + [`-d'|`--dynamic'] + [`-V'|`--version-info'] + [`-A'|`--arch-specific'] + [`-D'|`--use-dynamic'] + [`-x' <number or name>|`--hex-dump='<number or name>] + [`-p' <number or name>|`--string-dump='<number or name>] + [`-R' <number or name>|`--relocated-dump='<number or name>] + [`-c'|`--archive-index'] + [`-w[lLiaprmfFsoR]'| + `--debug-dump'[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges]] + [`-I'|`-histogram'] + [`-v'|`--version'] + [`-W'|`--wide'] + [`-H'|`--help'] + ELFFILE... + + `readelf' displays information about one or more ELF format object +files. The options control what particular information to display. + + ELFFILE... are the object files to be examined. 32-bit and 64-bit +ELF files are supported, as are archives containing ELF files. + + This program performs a similar function to `objdump' but it goes +into more detail and it exists independently of the BFD library, so if +there is a bug in BFD then readelf will not be affected. + + The long and short forms of options, shown here as alternatives, are +equivalent. At least one option besides `-v' or `-H' must be given. + +`-a' +`--all' + Equivalent to specifying `--file-header', `--program-headers', + `--sections', `--symbols', `--relocs', `--dynamic', `--notes' and + `--version-info'. + +`-h' +`--file-header' + Displays the information contained in the ELF header at the start + of the file. + +`-l' +`--program-headers' +`--segments' + Displays the information contained in the file's segment headers, + if it has any. + +`-S' +`--sections' +`--section-headers' + Displays the information contained in the file's section headers, + if it has any. + +`-g' +`--section-groups' + Displays the information contained in the file's section groups, + if it has any. + +`-t' +`--section-details' + Displays the detailed section information. Implies `-S'. + +`-s' +`--symbols' +`--syms' + Displays the entries in symbol table section of the file, if it + has one. + +`-e' +`--headers' + Display all the headers in the file. Equivalent to `-h -l -S'. + +`-n' +`--notes' + Displays the contents of the NOTE segments and/or sections, if any. + +`-r' +`--relocs' + Displays the contents of the file's relocation section, if it has + one. + +`-u' +`--unwind' + Displays the contents of the file's unwind section, if it has one. + Only the unwind sections for IA64 ELF files are currently + supported. + +`-d' +`--dynamic' + Displays the contents of the file's dynamic section, if it has one. + +`-V' +`--version-info' + Displays the contents of the version sections in the file, it they + exist. + +`-A' +`--arch-specific' + Displays architecture-specific information in the file, if there + is any. + +`-D' +`--use-dynamic' + When displaying symbols, this option makes `readelf' use the + symbol table in the file's dynamic section, rather than the one in + the symbols section. + +`-x <number or name>' +`--hex-dump=<number or name>' + Displays the contents of the indicated section as a hexadecimal + bytes. A number identifies a particular section by index in the + section table; any other string identifies all sections with that + name in the object file. + +`-R <number or name>' +`--relocated-dump=<number or name>' + Displays the contents of the indicated section as a hexadecimal + bytes. A number identifies a particular section by index in the + section table; any other string identifies all sections with that + name in the object file. The contents of the section will be + relocated before they are displayed. + +`-p <number or name>' +`--string-dump=<number or name>' + Displays the contents of the indicated section as printable + strings. A number identifies a particular section by index in the + section table; any other string identifies all sections with that + name in the object file. + +`-c' +`--archive-index' + Displays the file symbol index infomation contained in the header + part of binary archives. Performs the same function as the `t' + command to `ar', but without using the BFD library. *Note ar::. + +`-w[lLiaprmfFsoR]' +`--debug-dump[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges]' + Displays the contents of the debug sections in the file, if any are + present. If one of the optional letters or words follows the + switch then only data found in those specific sections will be + dumped. + + Note: the `=decodedline' option will display the interpreted + contents of a .debug_line section whereas the `=rawline' option + dumps the contents in a raw format. + +`-I' +`--histogram' + Display a histogram of bucket list lengths when displaying the + contents of the symbol tables. + +`-v' +`--version' + Display the version number of readelf. + +`-W' +`--wide' + Don't break output lines to fit into 80 columns. By default + `readelf' breaks section header and segment listing lines for + 64-bit ELF files, so that they fit into 80 columns. This option + causes `readelf' to print each section header resp. each segment + one a single line, which is far more readable on terminals wider + than 80 columns. + +`-H' +`--help' + Display the command line options understood by `readelf'. + + + +File: binutils.info, Node: Common Options, Next: Selecting the Target System, Prev: dlltool, Up: Top + +16 Common Options +***************** + +The following command-line options are supported by all of the programs +described in this manual. + +`@FILE' + Read command-line options from FILE. The options read are + inserted in place of the original @FILE option. If FILE does not + exist, or cannot be read, then the option will be treated + literally, and not removed. + + Options in FILE are separated by whitespace. A whitespace + character may be included in an option by surrounding the entire + option in either single or double quotes. Any character + (including a backslash) may be included by prefixing the character + to be included with a backslash. The FILE may itself contain + additional @FILE options; any such options will be processed + recursively. + +`--help' + Display the command-line options supported by the program. + +`--version' + Display the version number of the program. + + + +File: binutils.info, Node: Selecting the Target System, Next: Reporting Bugs, Prev: Common Options, Up: Top + +17 Selecting the Target System +****************************** + +You can specify two aspects of the target system to the GNU binary file +utilities, each in several ways: + + * the target + + * the architecture + + In the following summaries, the lists of ways to specify values are +in order of decreasing precedence. The ways listed first override those +listed later. + + The commands to list valid values only list the values for which the +programs you are running were configured. If they were configured with +`--enable-targets=all', the commands list most of the available values, +but a few are left out; not all targets can be configured in at once +because some of them can only be configured "native" (on hosts with the +same type as the target system). + +* Menu: + +* Target Selection:: +* Architecture Selection:: + + +File: binutils.info, Node: Target Selection, Next: Architecture Selection, Up: Selecting the Target System + +17.1 Target Selection +===================== + +A "target" is an object file format. A given target may be supported +for multiple architectures (*note Architecture Selection::). A target +selection may also have variations for different operating systems or +architectures. + + The command to list valid target values is `objdump -i' (the first +column of output contains the relevant information). + + Some sample values are: `a.out-hp300bsd', `ecoff-littlemips', +`a.out-sunos-big'. + + You can also specify a target using a configuration triplet. This is +the same sort of name that is passed to `configure' to specify a +target. When you use a configuration triplet as an argument, it must be +fully canonicalized. You can see the canonical version of a triplet by +running the shell script `config.sub' which is included with the +sources. + + Some sample configuration triplets are: `m68k-hp-bsd', +`mips-dec-ultrix', `sparc-sun-sunos'. + +`objdump' Target +---------------- + +Ways to specify: + + 1. command line option: `-b' or `--target' + + 2. environment variable `GNUTARGET' + + 3. deduced from the input file + +`objcopy' and `strip' Input Target +---------------------------------- + +Ways to specify: + + 1. command line options: `-I' or `--input-target', or `-F' or + `--target' + + 2. environment variable `GNUTARGET' + + 3. deduced from the input file + +`objcopy' and `strip' Output Target +----------------------------------- + +Ways to specify: + + 1. command line options: `-O' or `--output-target', or `-F' or + `--target' + + 2. the input target (see "`objcopy' and `strip' Input Target" above) + + 3. environment variable `GNUTARGET' + + 4. deduced from the input file + +`nm', `size', and `strings' Target +---------------------------------- + +Ways to specify: + + 1. command line option: `--target' + + 2. environment variable `GNUTARGET' + + 3. deduced from the input file + + +File: binutils.info, Node: Architecture Selection, Prev: Target Selection, Up: Selecting the Target System + +17.2 Architecture Selection +=========================== + +An "architecture" is a type of CPU on which an object file is to run. +Its name may contain a colon, separating the name of the processor +family from the name of the particular CPU. + + The command to list valid architecture values is `objdump -i' (the +second column contains the relevant information). + + Sample values: `m68k:68020', `mips:3000', `sparc'. + +`objdump' Architecture +---------------------- + +Ways to specify: + + 1. command line option: `-m' or `--architecture' + + 2. deduced from the input file + +`objcopy', `nm', `size', `strings' Architecture +----------------------------------------------- + +Ways to specify: + + 1. deduced from the input file + + +File: binutils.info, Node: Reporting Bugs, Next: GNU Free Documentation License, Prev: Selecting the Target System, Up: Top + +18 Reporting Bugs +***************** + +Your bug reports play an essential role in making the binary utilities +reliable. + + Reporting a bug may help you by bringing a solution to your problem, +or it may not. But in any case the principal function of a bug report +is to help the entire community by making the next version of the binary +utilities work better. Bug reports are your contribution to their +maintenance. + + In order for a bug report to serve its purpose, you must include the +information that enables us to fix the bug. + +* Menu: + +* Bug Criteria:: Have you found a bug? +* Bug Reporting:: How to report bugs + + +File: binutils.info, Node: Bug Criteria, Next: Bug Reporting, Up: Reporting Bugs + +18.1 Have You Found a Bug? +========================== + +If you are not sure whether you have found a bug, here are some +guidelines: + + * If a binary utility gets a fatal signal, for any input whatever, + that is a bug. Reliable utilities never crash. + + * If a binary utility produces an error message for valid input, + that is a bug. + + * If you are an experienced user of binary utilities, your + suggestions for improvement are welcome in any case. + + +File: binutils.info, Node: Bug Reporting, Prev: Bug Criteria, Up: Reporting Bugs + +18.2 How to Report Bugs +======================= + +A number of companies and individuals offer support for GNU products. +If you obtained the binary utilities from a support organization, we +recommend you contact that organization first. + + You can find contact information for many support companies and +individuals in the file `etc/SERVICE' in the GNU Emacs distribution. + + In any event, we also recommend that you send bug reports for the +binary utilities to `http://www.sourceware.org/bugzilla/'. + + The fundamental principle of reporting bugs usefully is this: +*report all the facts*. If you are not sure whether to state a fact or +leave it out, state it! + + Often people omit facts because they think they know what causes the +problem and assume that some details do not matter. Thus, you might +assume that the name of a file you use in an example does not matter. +Well, probably it does not, but one cannot be sure. Perhaps the bug is +a stray memory reference which happens to fetch from the location where +that pathname is stored in memory; perhaps, if the pathname were +different, the contents of that location would fool the utility into +doing the right thing despite the bug. Play it safe and give a +specific, complete example. That is the easiest thing for you to do, +and the most helpful. + + Keep in mind that the purpose of a bug report is to enable us to fix +the bug if it is new to us. Therefore, always write your bug reports +on the assumption that the bug has not been reported previously. + + Sometimes people give a few sketchy facts and ask, "Does this ring a +bell?" This cannot help us fix a bug, so it is basically useless. We +respond by asking for enough details to enable us to investigate. You +might as well expedite matters by sending them to begin with. + + To enable us to fix the bug, you should include all these things: + + * The version of the utility. Each utility announces it if you + start it with the `--version' argument. + + Without this, we will not know whether there is any point in + looking for the bug in the current version of the binary utilities. + + * Any patches you may have applied to the source, including any + patches made to the `BFD' library. + + * The type of machine you are using, and the operating system name + and version number. + + * What compiler (and its version) was used to compile the + utilities--e.g. "`gcc-2.7'". + + * The command arguments you gave the utility to observe the bug. To + guarantee you will not omit something important, list them all. A + copy of the Makefile (or the output from make) is sufficient. + + If we were to try to guess the arguments, we would probably guess + wrong and then we might not encounter the bug. + + * A complete input file, or set of input files, that will reproduce + the bug. If the utility is reading an object file or files, then + it is generally most helpful to send the actual object files. + + If the source files were produced exclusively using GNU programs + (e.g., `gcc', `gas', and/or the GNU `ld'), then it may be OK to + send the source files rather than the object files. In this case, + be sure to say exactly what version of `gcc', or whatever, was + used to produce the object files. Also say how `gcc', or + whatever, was configured. + + * A description of what behavior you observe that you believe is + incorrect. For example, "It gets a fatal signal." + + Of course, if the bug is that the utility gets a fatal signal, + then we will certainly notice it. But if the bug is incorrect + output, we might not notice unless it is glaringly wrong. You + might as well not give us a chance to make a mistake. + + Even if the problem you experience is a fatal signal, you should + still say so explicitly. Suppose something strange is going on, + such as your copy of the utility is out of sync, or you have + encountered a bug in the C library on your system. (This has + happened!) Your copy might crash and ours would not. If you told + us to expect a crash, then when ours fails to crash, we would know + that the bug was not happening for us. If you had not told us to + expect a crash, then we would not be able to draw any conclusion + from our observations. + + * If you wish to suggest changes to the source, send us context + diffs, as generated by `diff' with the `-u', `-c', or `-p' option. + Always send diffs from the old file to the new file. If you wish + to discuss something in the `ld' source, refer to it by context, + not by line number. + + The line numbers in our development sources will not match those + in your sources. Your line numbers would convey no useful + information to us. + + Here are some things that are not necessary: + + * A description of the envelope of the bug. + + Often people who encounter a bug spend a lot of time investigating + which changes to the input file will make the bug go away and which + changes will not affect it. + + This is often time consuming and not very useful, because the way + we will find the bug is by running a single example under the + debugger with breakpoints, not by pure deduction from a series of + examples. We recommend that you save your time for something else. + + Of course, if you can find a simpler example to report _instead_ + of the original one, that is a convenience for us. Errors in the + output will be easier to spot, running under the debugger will take + less time, and so on. + + However, simplification is not vital; if you do not want to do + this, report the bug anyway and send us the entire test case you + used. + + * A patch for the bug. + + A patch for the bug does help us if it is a good one. But do not + omit the necessary information, such as the test case, on the + assumption that a patch is all we need. We might see problems + with your patch and decide to fix the problem another way, or we + might not understand it at all. + + Sometimes with programs as complicated as the binary utilities it + is very hard to construct an example that will make the program + follow a certain path through the code. If you do not send us the + example, we will not be able to construct one, so we will not be + able to verify that the bug is fixed. + + And if we cannot understand what bug you are trying to fix, or why + your patch should be an improvement, we will not install it. A + test case will help us to understand. + + * A guess about what the bug is or what it depends on. + + Such guesses are usually wrong. Even we cannot guess right about + such things without first using the debugger to find the facts. + + +File: binutils.info, Node: GNU Free Documentation License, Next: Binutils Index, Prev: Reporting Bugs, Up: Top + +Appendix A GNU Free Documentation License +***************************************** + + Version 1.3, 3 November 2008 + + Copyright (C) 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc. + `http://fsf.org/' + + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + 0. PREAMBLE + + The purpose of this License is to make a manual, textbook, or other + functional and useful document "free" in the sense of freedom: to + assure everyone the effective freedom to copy and redistribute it, + with or without modifying it, either commercially or + noncommercially. Secondarily, this License preserves for the + author and publisher a way to get credit for their work, while not + being considered responsible for modifications made by others. + + This License is a kind of "copyleft", which means that derivative + works of the document must themselves be free in the same sense. + It complements the GNU General Public License, which is a copyleft + license designed for free software. + + We have designed this License in order to use it for manuals for + free software, because free software needs free documentation: a + free program should come with manuals providing the same freedoms + that the software does. But this License is not limited to + software manuals; it can be used for any textual work, regardless + of subject matter or whether it is published as a printed book. + We recommend this License principally for works whose purpose is + instruction or reference. + + 1. APPLICABILITY AND DEFINITIONS + + This License applies to any manual or other work, in any medium, + that contains a notice placed by the copyright holder saying it + can be distributed under the terms of this License. Such a notice + grants a world-wide, royalty-free license, unlimited in duration, + to use that work under the conditions stated herein. The + "Document", below, refers to any such manual or work. Any member + of the public is a licensee, and is addressed as "you". You + accept the license if you copy, modify or distribute the work in a + way requiring permission under copyright law. + + A "Modified Version" of the Document means any work containing the + Document or a portion of it, either copied verbatim, or with + modifications and/or translated into another language. + + A "Secondary Section" is a named appendix or a front-matter section + of the Document that deals exclusively with the relationship of the + publishers or authors of the Document to the Document's overall + subject (or to related matters) and contains nothing that could + fall directly within that overall subject. (Thus, if the Document + is in part a textbook of mathematics, a Secondary Section may not + explain any mathematics.) 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For + works in formats which do not have any title page as such, "Title + Page" means the text near the most prominent appearance of the + work's title, preceding the beginning of the body of the text. + + The "publisher" means any person or entity that distributes copies + of the Document to the public. + + A section "Entitled XYZ" means a named subunit of the Document + whose title either is precisely XYZ or contains XYZ in parentheses + following text that translates XYZ in another language. (Here XYZ + stands for a specific section name mentioned below, such as + "Acknowledgements", "Dedications", "Endorsements", or "History".) + To "Preserve the Title" of such a section when you modify the + Document means that it remains a section "Entitled XYZ" according + to this definition. + + The Document may include Warranty Disclaimers next to the notice + which states that this License applies to the Document. These + Warranty Disclaimers are considered to be included by reference in + this License, but only as regards disclaiming warranties: any other + implication that these Warranty Disclaimers may have is void and + has no effect on the meaning of this License. + + 2. VERBATIM COPYING + + You may copy and distribute the Document in any medium, either + commercially or noncommercially, provided that this License, the + copyright notices, and the license notice saying this License + applies to the Document are reproduced in all copies, and that you + add no other conditions whatsoever to those of this License. You + may not use technical measures to obstruct or control the reading + or further copying of the copies you make or distribute. However, + you may accept compensation in exchange for copies. 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If you use the + latter option, you must take reasonably prudent steps, when you + begin distribution of Opaque copies in quantity, to ensure that + this Transparent copy will remain thus accessible at the stated + location until at least one year after the last time you + distribute an Opaque copy (directly or through your agents or + retailers) of that edition to the public. + + It is requested, but not required, that you contact the authors of + the Document well before redistributing any large number of + copies, to give them a chance to provide you with an updated + version of the Document. + + 4. MODIFICATIONS + + You may copy and distribute a Modified Version of the Document + under the conditions of sections 2 and 3 above, provided that you + release the Modified Version under precisely this License, with + the Modified Version filling the role of the Document, thus + licensing distribution and modification of the Modified Version to + whoever possesses a copy of it. In addition, you must do these + things in the Modified Version: + + A. Use in the Title Page (and on the covers, if any) a title + distinct from that of the Document, and from those of + previous versions (which should, if there were any, be listed + in the History section of the Document). You may use the + same title as a previous version if the original publisher of + that version gives permission. + + B. List on the Title Page, as authors, one or more persons or + entities responsible for authorship of the modifications in + the Modified Version, together with at least five of the + principal authors of the Document (all of its principal + authors, if it has fewer than five), unless they release you + from this requirement. + + C. State on the Title page the name of the publisher of the + Modified Version, as the publisher. + + D. Preserve all the copyright notices of the Document. + + E. Add an appropriate copyright notice for your modifications + adjacent to the other copyright notices. + + F. Include, immediately after the copyright notices, a license + notice giving the public permission to use the Modified + Version under the terms of this License, in the form shown in + the Addendum below. + + G. Preserve in that license notice the full lists of Invariant + Sections and required Cover Texts given in the Document's + license notice. + + H. Include an unaltered copy of this License. + + I. Preserve the section Entitled "History", Preserve its Title, + and add to it an item stating at least the title, year, new + authors, and publisher of the Modified Version as given on + the Title Page. If there is no section Entitled "History" in + the Document, create one stating the title, year, authors, + and publisher of the Document as given on its Title Page, + then add an item describing the Modified Version as stated in + the previous sentence. + + J. Preserve the network location, if any, given in the Document + for public access to a Transparent copy of the Document, and + likewise the network locations given in the Document for + previous versions it was based on. These may be placed in + the "History" section. You may omit a network location for a + work that was published at least four years before the + Document itself, or if the original publisher of the version + it refers to gives permission. + + K. For any section Entitled "Acknowledgements" or "Dedications", + Preserve the Title of the section, and preserve in the + section all the substance and tone of each of the contributor + acknowledgements and/or dedications given therein. + + L. Preserve all the Invariant Sections of the Document, + unaltered in their text and in their titles. Section numbers + or the equivalent are not considered part of the section + titles. + + M. Delete any section Entitled "Endorsements". Such a section + may not be included in the Modified Version. + + N. Do not retitle any existing section to be Entitled + "Endorsements" or to conflict in title with any Invariant + Section. + + O. Preserve any Warranty Disclaimers. + + If the Modified Version includes new front-matter sections or + appendices that qualify as Secondary Sections and contain no + material copied from the Document, you may at your option + designate some or all of these sections as invariant. To do this, + add their titles to the list of Invariant Sections in the Modified + Version's license notice. These titles must be distinct from any + other section titles. + + You may add a section Entitled "Endorsements", provided it contains + nothing but endorsements of your Modified Version by various + parties--for example, statements of peer review or that the text + has been approved by an organization as the authoritative + definition of a standard. + + You may add a passage of up to five words as a Front-Cover Text, + and a passage of up to 25 words as a Back-Cover Text, to the end + of the list of Cover Texts in the Modified Version. Only one + passage of Front-Cover Text and one of Back-Cover Text may be + added by (or through arrangements made by) any one entity. If the + Document already includes a cover text for the same cover, + previously added by you or by arrangement made by the same entity + you are acting on behalf of, you may not add another; but you may + replace the old one, on explicit permission from the previous + publisher that added the old one. + + The author(s) and publisher(s) of the Document do not by this + License give permission to use their names for publicity for or to + assert or imply endorsement of any Modified Version. + + 5. COMBINING DOCUMENTS + + You may combine the Document with other documents released under + this License, under the terms defined in section 4 above for + modified versions, provided that you include in the combination + all of the Invariant Sections of all of the original documents, + unmodified, and list them all as Invariant Sections of your + combined work in its license notice, and that you preserve all + their Warranty Disclaimers. + + The combined work need only contain one copy of this License, and + multiple identical Invariant Sections may be replaced with a single + copy. If there are multiple Invariant Sections with the same name + but different contents, make the title of each such section unique + by adding at the end of it, in parentheses, the name of the + original author or publisher of that section if known, or else a + unique number. Make the same adjustment to the section titles in + the list of Invariant Sections in the license notice of the + combined work. + + In the combination, you must combine any sections Entitled + "History" in the various original documents, forming one section + Entitled "History"; likewise combine any sections Entitled + "Acknowledgements", and any sections Entitled "Dedications". You + must delete all sections Entitled "Endorsements." + + 6. COLLECTIONS OF DOCUMENTS + + You may make a collection consisting of the Document and other + documents released under this License, and replace the individual + copies of this License in the various documents with a single copy + that is included in the collection, provided that you follow the + rules of this License for verbatim copying of each of the + documents in all other respects. + + You may extract a single document from such a collection, and + distribute it individually under this License, provided you insert + a copy of this License into the extracted document, and follow + this License in all other respects regarding verbatim copying of + that document. + + 7. AGGREGATION WITH INDEPENDENT WORKS + + A compilation of the Document or its derivatives with other + separate and independent documents or works, in or on a volume of + a storage or distribution medium, is called an "aggregate" if the + copyright resulting from the compilation is not used to limit the + legal rights of the compilation's users beyond what the individual + works permit. When the Document is included in an aggregate, this + License does not apply to the other works in the aggregate which + are not themselves derivative works of the Document. + + If the Cover Text requirement of section 3 is applicable to these + copies of the Document, then if the Document is less than one half + of the entire aggregate, the Document's Cover Texts may be placed + on covers that bracket the Document within the aggregate, or the + electronic equivalent of covers if the Document is in electronic + form. Otherwise they must appear on printed covers that bracket + the whole aggregate. + + 8. TRANSLATION + + Translation is considered a kind of modification, so you may + distribute translations of the Document under the terms of section + 4. Replacing Invariant Sections with translations requires special + permission from their copyright holders, but you may include + translations of some or all Invariant Sections in addition to the + original versions of these Invariant Sections. You may include a + translation of this License, and all the license notices in the + Document, and any Warranty Disclaimers, provided that you also + include the original English version of this License and the + original versions of those notices and disclaimers. In case of a + disagreement between the translation and the original version of + this License or a notice or disclaimer, the original version will + prevail. + + If a section in the Document is Entitled "Acknowledgements", + "Dedications", or "History", the requirement (section 4) to + Preserve its Title (section 1) will typically require changing the + actual title. + + 9. TERMINATION + + You may not copy, modify, sublicense, or distribute the Document + except as expressly provided under this License. Any attempt + otherwise to copy, modify, sublicense, or distribute it is void, + and will automatically terminate your rights under this License. + + However, if you cease all violation of this License, then your + license from a particular copyright holder is reinstated (a) + provisionally, unless and until the copyright holder explicitly + and finally terminates your license, and (b) permanently, if the + copyright holder fails to notify you of the violation by some + reasonable means prior to 60 days after the cessation. + + Moreover, your license from a particular copyright holder is + reinstated permanently if the copyright holder notifies you of the + violation by some reasonable means, this is the first time you have + received notice of violation of this License (for any work) from + that copyright holder, and you cure the violation prior to 30 days + after your receipt of the notice. + + Termination of your rights under this section does not terminate + the licenses of parties who have received copies or rights from + you under this License. If your rights have been terminated and + not permanently reinstated, receipt of a copy of some or all of + the same material does not give you any rights to use it. + + 10. FUTURE REVISIONS OF THIS LICENSE + + The Free Software Foundation may publish new, revised versions of + the GNU Free Documentation License from time to time. Such new + versions will be similar in spirit to the present version, but may + differ in detail to address new problems or concerns. See + `http://www.gnu.org/copyleft/'. + + Each version of the License is given a distinguishing version + number. If the Document specifies that a particular numbered + version of this License "or any later version" applies to it, you + have the option of following the terms and conditions either of + that specified version or of any later version that has been + published (not as a draft) by the Free Software Foundation. If + the Document does not specify a version number of this License, + you may choose any version ever published (not as a draft) by the + Free Software Foundation. If the Document specifies that a proxy + can decide which future versions of this License can be used, that + proxy's public statement of acceptance of a version permanently + authorizes you to choose that version for the Document. + + 11. RELICENSING + + "Massive Multiauthor Collaboration Site" (or "MMC Site") means any + World Wide Web server that publishes copyrightable works and also + provides prominent facilities for anybody to edit those works. A + public wiki that anybody can edit is an example of such a server. + A "Massive Multiauthor Collaboration" (or "MMC") contained in the + site means any set of copyrightable works thus published on the MMC + site. + + "CC-BY-SA" means the Creative Commons Attribution-Share Alike 3.0 + license published by Creative Commons Corporation, a not-for-profit + corporation with a principal place of business in San Francisco, + California, as well as future copyleft versions of that license + published by that same organization. + + "Incorporate" means to publish or republish a Document, in whole or + in part, as part of another Document. + + An MMC is "eligible for relicensing" if it is licensed under this + License, and if all works that were first published under this + License somewhere other than this MMC, and subsequently + incorporated in whole or in part into the MMC, (1) had no cover + texts or invariant sections, and (2) were thus incorporated prior + to November 1, 2008. + + The operator of an MMC Site may republish an MMC contained in the + site under CC-BY-SA on the same site at any time before August 1, + 2009, provided the MMC is eligible for relicensing. + + +ADDENDUM: How to use this License for your documents +==================================================== + +To use this License in a document you have written, include a copy of +the License in the document and put the following copyright and license +notices just after the title page: + + Copyright (C) YEAR YOUR NAME. + Permission is granted to copy, distribute and/or modify this document + under the terms of the GNU Free Documentation License, Version 1.3 + or any later version published by the Free Software Foundation; + with no Invariant Sections, no Front-Cover Texts, and no Back-Cover + Texts. A copy of the license is included in the section entitled ``GNU + Free Documentation License''. + + If you have Invariant Sections, Front-Cover Texts and Back-Cover +Texts, replace the "with...Texts." line with this: + + with the Invariant Sections being LIST THEIR TITLES, with + the Front-Cover Texts being LIST, and with the Back-Cover Texts + being LIST. + + If you have Invariant Sections without Cover Texts, or some other +combination of the three, merge those two alternatives to suit the +situation. + + If your document contains nontrivial examples of program code, we +recommend releasing these examples in parallel under your choice of +free software license, such as the GNU General Public License, to +permit their use in free software. + + +File: binutils.info, Node: Binutils Index, Prev: GNU Free Documentation License, Up: Top + +Binutils Index +************** + + +* Menu: + +* .stab: objdump. (line 370) +* Add prefix to absolute paths: objdump. (line 341) +* addr2line: addr2line. (line 6) +* address to file name and line number: addr2line. (line 6) +* all header information, object file: objdump. (line 489) +* ar: ar. (line 6) +* ar compatibility: ar. (line 50) +* architecture: objdump. (line 195) +* architectures available: objdump. (line 180) +* archive contents: ranlib. (line 6) +* Archive file symbol index information: readelf. (line 147) +* archive headers: objdump. (line 65) +* archives: ar. (line 6) +* base files: dlltool. (line 123) +* bug criteria: Bug Criteria. (line 6) +* bug reports: Bug Reporting. (line 6) +* bugs: Reporting Bugs. (line 6) +* bugs, reporting: Bug Reporting. (line 6) +* c++filt: c++filt. (line 6) +* changing object addresses: objcopy. (line 282) +* changing section address: objcopy. (line 292) +* changing section LMA: objcopy. (line 300) +* changing section VMA: objcopy. (line 313) +* changing start address: objcopy. (line 277) +* collections of files: ar. (line 6) +* compatibility, ar: ar. (line 50) +* contents of archive: ar cmdline. (line 88) +* crash: Bug Criteria. (line 9) +* creating archives: ar cmdline. (line 129) +* creating thin archive: ar cmdline. (line 190) +* cxxfilt: c++filt. (line 14) +* dates in archive: ar cmdline. (line 164) +* debug symbols: objdump. (line 370) +* debugging symbols: nm. (line 141) +* deleting from archive: ar cmdline. (line 26) +* demangling C++ symbols: c++filt. (line 6) +* demangling in nm: nm. (line 149) +* demangling in objdump <1>: addr2line. (line 55) +* demangling in objdump: objdump. (line 93) +* deterministic archives: ar cmdline. (line 135) +* disassembling object code: objdump. (line 115) +* disassembly architecture: objdump. (line 195) +* disassembly endianness: objdump. (line 135) +* disassembly, with source: objdump. (line 337) +* discarding symbols: strip. (line 6) +* DLL: dlltool. (line 6) +* dlltool: dlltool. (line 6) +* DWARF: objdump. (line 363) +* dynamic relocation entries, in object file: objdump. (line 325) +* dynamic symbol table entries, printing: objdump. (line 473) +* dynamic symbols: nm. (line 161) +* ELF dynamic section information: readelf. (line 105) +* ELF file header information: readelf. (line 54) +* ELF file information: readelf. (line 6) +* ELF notes: readelf. (line 90) +* ELF object file format: objdump. (line 370) +* ELF program header information: readelf. (line 60) +* ELF reloc information: readelf. (line 94) +* ELF section group information: readelf. (line 71) +* ELF section information: readelf. (line 66) +* ELF segment information: readelf. (line 60) +* ELF symbol table information: readelf. (line 81) +* ELF version sections informations: readelf. (line 109) +* endianness: objdump. (line 135) +* error on valid input: Bug Criteria. (line 12) +* external symbols: nm. (line 253) +* extract from archive: ar cmdline. (line 103) +* fatal signal: Bug Criteria. (line 9) +* file name: nm. (line 135) +* header information, all: objdump. (line 489) +* input .def file: dlltool. (line 119) +* input file name: nm. (line 135) +* Instruction width: objdump. (line 358) +* libraries: ar. (line 25) +* listings strings: strings. (line 6) +* load plugin: nm. (line 176) +* machine instructions: objdump. (line 115) +* moving in archive: ar cmdline. (line 34) +* MRI compatibility, ar: ar scripts. (line 8) +* name duplication in archive: ar cmdline. (line 97) +* name length: ar. (line 18) +* nm: nm. (line 6) +* nm compatibility: nm. (line 167) +* nm format: nm. (line 145) +* not writing archive index: ar cmdline. (line 183) +* objdump: objdump. (line 6) +* object code format <1>: addr2line. (line 50) +* object code format <2>: strings. (line 67) +* object code format <3>: objdump. (line 79) +* object code format <4>: size. (line 84) +* object code format: nm. (line 244) +* object file header: objdump. (line 141) +* object file information: objdump. (line 6) +* object file offsets: objdump. (line 146) +* object file sections: objdump. (line 332) +* object formats available: objdump. (line 180) +* operations on archive: ar cmdline. (line 22) +* printing from archive: ar cmdline. (line 46) +* printing strings: strings. (line 6) +* quick append to archive: ar cmdline. (line 54) +* radix for section sizes: size. (line 66) +* ranlib: ranlib. (line 6) +* readelf: readelf. (line 6) +* relative placement in archive: ar cmdline. (line 117) +* relocation entries, in object file: objdump. (line 319) +* removing symbols: strip. (line 6) +* repeated names in archive: ar cmdline. (line 97) +* replacement in archive: ar cmdline. (line 70) +* reporting bugs: Reporting Bugs. (line 6) +* scripts, ar: ar scripts. (line 8) +* section addresses in objdump: objdump. (line 71) +* section headers: objdump. (line 162) +* section information: objdump. (line 185) +* section sizes: size. (line 6) +* sections, full contents: objdump. (line 332) +* size: size. (line 6) +* size display format: size. (line 27) +* size number format: size. (line 66) +* sorting symbols: nm. (line 197) +* source code context: objdump. (line 155) +* source disassembly: objdump. (line 337) +* source file name: nm. (line 135) +* source filenames for object files: objdump. (line 189) +* stab: objdump. (line 370) +* start-address: objdump. (line 380) +* stop-address: objdump. (line 384) +* strings: strings. (line 6) +* strings, printing: strings. (line 6) +* strip: strip. (line 6) +* Strip absolute paths: objdump. (line 344) +* symbol index <1>: ranlib. (line 6) +* symbol index: ar. (line 28) +* symbol index, listing: nm. (line 214) +* symbol line numbers: nm. (line 182) +* symbol table entries, printing: objdump. (line 389) +* symbols: nm. (line 6) +* symbols, discarding: strip. (line 6) +* thin archives: ar. (line 40) +* undefined symbols: nm. (line 249) +* Unix compatibility, ar: ar cmdline. (line 8) +* unwind information: readelf. (line 99) +* updating an archive: ar cmdline. (line 195) +* version: Top. (line 6) +* VMA in objdump: objdump. (line 71) +* wide output, printing: objdump. (line 495) +* writing archive index: ar cmdline. (line 177) + + + +Tag Table: +Node: Top1929 +Node: ar3572 +Node: ar cmdline6377 +Node: ar scripts15420 +Node: nm21108 +Node: objcopy30582 +Node: objdump58823 +Node: ranlib79295 +Node: size80116 +Node: strings83121 +Node: strip85579 +Node: c++filt91530 +Ref: c++filt-Footnote-196375 +Node: addr2line96481 +Node: nlmconv99752 +Node: windmc102358 +Node: windres106005 +Node: dlltool112032 +Node: def file format124716 +Node: readelf126454 +Node: Common Options132460 +Node: Selecting the Target System133500 +Node: Target Selection134432 +Node: Architecture Selection136414 +Node: Reporting Bugs137242 +Node: Bug Criteria138021 +Node: Bug Reporting138574 +Node: GNU Free Documentation License145444 +Node: Binutils Index170623 + +End Tag Table diff --git a/uclibc-crosstools-gcc-4.4.2-1/usr/share/info/configure.info b/uclibc-crosstools-gcc-4.4.2-1/usr/share/info/configure.info new file mode 100644 index 0000000..cee206a --- /dev/null +++ b/uclibc-crosstools-gcc-4.4.2-1/usr/share/info/configure.info @@ -0,0 +1,2773 @@ +This is configure.info, produced by makeinfo version 4.8 from +./configure.texi. + +INFO-DIR-SECTION GNU admin +START-INFO-DIR-ENTRY +* configure: (configure). The GNU configure and build system +END-INFO-DIR-ENTRY + + This file documents the GNU configure and build system. + + Copyright (C) 1998 Cygnus Solutions. + + Permission is granted to make and distribute verbatim copies of this +manual provided the copyright notice and this permission notice are +preserved on all copies. + + Permission is granted to copy and distribute modified versions of +this manual under the conditions for verbatim copying, provided that +the entire resulting derived work is distributed under the terms of a +permission notice identical to this one. + + Permission is granted to copy and distribute translations of this +manual into another language, under the above conditions for modified +versions, except that this permission notice may be stated in a +translation approved by the Foundation. + + +File: configure.info, Node: Top, Next: Introduction, Up: (dir) + +GNU configure and build system +****************************** + +The GNU configure and build system. + +* Menu: + +* Introduction:: Introduction. +* Getting Started:: Getting Started. +* Files:: Files. +* Configuration Names:: Configuration Names. +* Cross Compilation Tools:: Cross Compilation Tools. +* Canadian Cross:: Canadian Cross. +* Cygnus Configure:: Cygnus Configure. +* Multilibs:: Multilibs. +* FAQ:: Frequently Asked Questions. +* Index:: Index. + + +File: configure.info, Node: Introduction, Next: Getting Started, Prev: Top, Up: Top + +1 Introduction +************** + +This document describes the GNU configure and build systems. It +describes how autoconf, automake, libtool, and make fit together. It +also includes a discussion of the older Cygnus configure system. + + This document does not describe in detail how to use each of the +tools; see the respective manuals for that. Instead, it describes +which files the developer must write, which files are machine generated +and how they are generated, and where certain common problems should be +addressed. + + This document draws on several sources, including the autoconf +manual by David MacKenzie (*note autoconf overview: (autoconf)Top.), +the automake manual by David MacKenzie and Tom Tromey (*note automake +overview: (automake)Top.), the libtool manual by Gordon Matzigkeit +(*note libtool overview: (libtool)Top.), and the Cygnus configure +manual by K. Richard Pixley. + +* Menu: + +* Goals:: Goals. +* Tools:: The tools. +* History:: History. +* Building:: Building. + + +File: configure.info, Node: Goals, Next: Tools, Up: Introduction + +1.1 Goals +========= + +The GNU configure and build system has two main goals. + + The first is to simplify the development of portable programs. The +system permits the developer to concentrate on writing the program, +simplifying many details of portability across Unix and even Windows +systems, and permitting the developer to describe how to build the +program using simple rules rather than complex Makefiles. + + The second is to simplify the building of programs distributed as +source code. All programs are built using a simple, standardized, two +step process. The program builder need not install any special tools in +order to build the program. + + +File: configure.info, Node: Tools, Next: History, Prev: Goals, Up: Introduction + +1.2 Tools +========= + +The GNU configure and build system is comprised of several different +tools. Program developers must build and install all of these tools. + + People who just want to build programs from distributed sources +normally do not need any special tools beyond a Unix shell, a make +program, and a C compiler. + +autoconf + provides a general portability framework, based on testing the + features of the host system at build time. + +automake + a system for describing how to build a program, permitting the + developer to write a simplified `Makefile'. + +libtool + a standardized approach to building shared libraries. + +gettext + provides a framework for translation of text messages into other + languages; not really discussed in this document. + +m4 + autoconf requires the GNU version of m4; the standard Unix m4 does + not suffice. + +perl + automake requires perl. + + +File: configure.info, Node: History, Next: Building, Prev: Tools, Up: Introduction + +1.3 History +=========== + +This is a very brief and probably inaccurate history. + + As the number of Unix variants increased during the 1980s, it became +harder to write programs which could run on all variants. While it was +often possible to use `#ifdef' to identify particular systems, +developers frequently did not have access to every system, and the +characteristics of some systems changed from version to version. + + By 1992, at least three different approaches had been developed: + * The Metaconfig program, by Larry Wall, Harlan Stenn, and Raphael + Manfredi. + + * The Cygnus configure script, by K. Richard Pixley, and the gcc + configure script, by Richard Stallman. These use essentially the + same approach, and the developers communicated regularly. + + * The autoconf program, by David MacKenzie. + + The Metaconfig program is still used for Perl and a few other +programs. It is part of the Dist package. I do not know if it is +being developed. + + In 1994, David MacKenzie and others modified autoconf to incorporate +all the features of Cygnus configure. Since then, there has been a +slow but steady conversion of GNU programs from Cygnus configure to +autoconf. gcc has been converted, eliminating the gcc configure script. + + GNU autoconf was regularly maintained until late 1996. As of this +writing in June, 1998, it has no public maintainer. + + Most programs are built using the make program, which requires the +developer to write Makefiles describing how to build the programs. +Since most programs are built in pretty much the same way, this led to a +lot of duplication. + + The X Window system is built using the imake tool, which uses a +database of rules to eliminate the duplication. However, building a +tool which was developed using imake requires that the builder have +imake installed, violating one of the goals of the GNU system. + + The new BSD make provides a standard library of Makefile fragments, +which permits developers to write very simple Makefiles. However, this +requires that the builder install the new BSD make program. + + In 1994, David MacKenzie wrote the first version of automake, which +permitted writing a simple build description which was converted into a +Makefile which could be used by the standard make program. In 1995, Tom +Tromey completely rewrote automake in Perl, and he continues to enhance +it. + + Various free packages built libraries, and by around 1995 several +included support to build shared libraries on various platforms. +However, there was no consistent approach. In early 1996, Gordon +Matzigkeit began working on libtool, which provided a standardized +approach to building shared libraries. This was integrated into +automake from the start. + + The development of automake and libtool was driven by the GNITS +project, a group of GNU maintainers who designed standardized tools to +help meet the GNU coding standards. + + +File: configure.info, Node: Building, Prev: History, Up: Introduction + +1.4 Building +============ + +Most readers of this document should already know how to build a tool by +running `configure' and `make'. This section may serve as a quick +introduction or reminder. + + Building a tool is normally as simple as running `configure' +followed by `make'. You should normally run `configure' from an empty +directory, using some path to refer to the `configure' script in the +source directory. The directory in which you run `configure' is called +the "object directory". + + In order to use a object directory which is different from the source +directory, you must be using the GNU version of `make', which has the +required `VPATH' support. Despite this restriction, using a different +object directory is highly recommended: + * It keeps the files generated during the build from cluttering up + your sources. + + * It permits you to remove the built files by simply removing the + entire build directory. + + * It permits you to build from the same sources with several sets of + configure options simultaneously. + + If you don't have GNU `make', you will have to run `configure' in +the source directory. All GNU packages should support this; in +particular, GNU packages should not assume the presence of GNU `make'. + + After running `configure', you can build the tools by running `make'. + + To install the tools, run `make install'. Installing the tools will +copy the programs and any required support files to the "installation +directory". The location of the installation directory is controlled +by `configure' options, as described below. + + In the Cygnus tree at present, the info files are built and +installed as a separate step. To build them, run `make info'. To +install them, run `make install-info'. The equivalent html files are +also built and installed in a separate step. To build the html files, +run `make html'. To install the html files run `make install-html'. + + All `configure' scripts support a wide variety of options. The most +interesting ones are `--with' and `--enable' options which are +generally specific to particular tools. You can usually use the +`--help' option to get a list of interesting options for a particular +configure script. + + The only generic options you are likely to use are the `--prefix' +and `--exec-prefix' options. These options are used to specify the +installation directory. + + The directory named by the `--prefix' option will hold machine +independent files such as info files. + + The directory named by the `--exec-prefix' option, which is normally +a subdirectory of the `--prefix' directory, will hold machine dependent +files such as executables. + + The default for `--prefix' is `/usr/local'. The default for +`--exec-prefix' is the value used for `--prefix'. + + The convention used in Cygnus releases is to use a `--prefix' option +of `/usr/cygnus/RELEASE', where RELEASE is the name of the release, and +to use a `--exec-prefix' option of `/usr/cygnus/RELEASE/H-HOST', where +HOST is the configuration name of the host system (*note Configuration +Names::). + + Do not use either the source or the object directory as the +installation directory. That will just lead to confusion. + + +File: configure.info, Node: Getting Started, Next: Files, Prev: Introduction, Up: Top + +2 Getting Started +***************** + +To start using the GNU configure and build system with your software +package, you must write three files, and you must run some tools to +manually generate additional files. + +* Menu: + +* Write configure.in:: Write configure.in. +* Write Makefile.am:: Write Makefile.am. +* Write acconfig.h:: Write acconfig.h. +* Generate files:: Generate files. +* Getting Started Example:: Example. + + +File: configure.info, Node: Write configure.in, Next: Write Makefile.am, Up: Getting Started + +2.1 Write configure.in +====================== + +You must first write the file `configure.in'. This is an autoconf +input file, and the autoconf manual describes in detail what this file +should look like. + + You will write tests in your `configure.in' file to check for +conditions that may change from one system to another, such as the +presence of particular header files or functions. + + For example, not all systems support the `gettimeofday' function. +If you want to use the `gettimeofday' function when it is available, +and to use some other function when it is not, you would check for this +by putting `AC_CHECK_FUNCS(gettimeofday)' in `configure.in'. + + When the configure script is run at build time, this will arrange to +define the preprocessor macro `HAVE_GETTIMEOFDAY' to the value 1 if the +`gettimeofday' function is available, and to not define the macro at +all if the function is not available. Your code can then use `#ifdef' +to test whether it is safe to call `gettimeofday'. + + If you have an existing body of code, the `autoscan' program may +help identify potential portability problems, and hence configure tests +that you will want to use. *Note Invoking autoscan: (autoconf)Invoking +autoscan. + + Another handy tool for an existing body of code is `ifnames'. This +will show you all the preprocessor conditionals that the code already +uses. *Note Invoking ifnames: (autoconf)Invoking ifnames. + + Besides the portability tests which are specific to your particular +package, every `configure.in' file should contain the following macros. + +`AC_INIT' + This macro takes a single argument, which is the name of a file in + your package. For example, `AC_INIT(foo.c)'. + +`AC_PREREQ(VERSION)' + This macro is optional. It may be used to indicate the version of + `autoconf' that you are using. This will prevent users from + running an earlier version of `autoconf' and perhaps getting an + invalid `configure' script. For example, `AC_PREREQ(2.12)'. + +`AM_INIT_AUTOMAKE' + This macro takes two arguments: the name of the package, and a + version number. For example, `AM_INIT_AUTOMAKE(foo, 1.0)'. (This + macro is not needed if you are not using automake). + +`AM_CONFIG_HEADER' + This macro names the header file which will hold the preprocessor + macro definitions at run time. Normally this should be + `config.h'. Your sources would then use `#include "config.h"' to + include it. + + This macro may optionally name the input file for that header + file; by default, this is `config.h.in', but that file name works + poorly on DOS filesystems. Therefore, it is often better to name + it explicitly as `config.in'. + + This is what you should normally put in `configure.in': + AM_CONFIG_HEADER(config.h:config.in) + + (If you are not using automake, use `AC_CONFIG_HEADER' rather than + `AM_CONFIG_HEADER'). + +`AM_MAINTAINER_MODE' + This macro always appears in Cygnus configure scripts. Other + programs may or may not use it. + + If this macro is used, the `--enable-maintainer-mode' option is + required to enable automatic rebuilding of generated files used by + the configure system. This of course requires that developers be + aware of, and use, that option. + + If this macro is not used, then the generated files will always be + rebuilt automatically. This will cause problems if the wrong + versions of autoconf, automake, or others are in the builder's + `PATH'. + + (If you are not using automake, you do not need to use this macro). + +`AC_EXEEXT' + Either this macro or `AM_EXEEXT' always appears in Cygnus configure + files. Other programs may or may not use one of them. + + This macro looks for the executable suffix used on the host + system. On Unix systems, this is the empty string. On Windows + systems, this is `.exe'. This macro directs automake to use the + executable suffix as appropriate when creating programs. This + macro does not take any arguments. + + The `AC_EXEEXT' form is new, and is part of a Cygnus patch to + autoconf to support compiling with Visual C++. Older programs use + `AM_EXEEXT' instead. + + (Programs which do not use automake use neither `AC_EXEEXT' nor + `AM_EXEEXT'). + +`AC_PROG_CC' + If you are writing C code, you will normally want to use this + macro. It locates the C compiler to use. It does not take any + arguments. + + However, if this `configure.in' file is for a library which is to + be compiled by a cross compiler which may not fully work, then you + will not want to use `AC_PROG_CC'. Instead, you will want to use a + variant which does not call the macro `AC_PROG_CC_WORKS'. Examples + can be found in various `configure.in' files for libraries that are + compiled with cross compilers, such as libiberty or libgloss. + This is essentially a bug in autoconf, and there will probably be + a better workaround at some point. + +`AC_PROG_CXX' + If you are writing C++ code, you will want to use this macro. It + locates the C++ compiler to use. It does not take any arguments. + The same cross compiler comments apply as for `AC_PROG_CC'. + +`AM_PROG_LIBTOOL' + If you want to build libraries, and you want to permit them to be + shared, or you want to link against libraries which were built + using libtool, then you will need this macro. This macro is + required in order to use libtool. + + By default, this will cause all libraries to be built as shared + libraries. To prevent this-to change the default-use + `AM_DISABLE_SHARED' before `AM_PROG_LIBTOOL'. The configure + options `--enable-shared' and `--disable-shared' may be used to + override the default at build time. + +`AC_DEFINE(_GNU_SOURCE)' + GNU packages should normally include this line before any other + feature tests. This defines the macro `_GNU_SOURCE' when + compiling, which directs the libc header files to provide the + standard GNU system interfaces including all GNU extensions. If + this macro is not defined, certain GNU extensions may not be + available. + +`AC_OUTPUT' + This macro takes a list of file names which the configure process + should produce. This is normally a list of one or more `Makefile' + files in different directories. If your package lives entirely in + a single directory, you would use simply `AC_OUTPUT(Makefile)'. + If you also have, for example, a `lib' subdirectory, you would use + `AC_OUTPUT(Makefile lib/Makefile)'. + + If you want to use locally defined macros in your `configure.in' +file, then you will need to write a `acinclude.m4' file which defines +them (if not using automake, this file is called `aclocal.m4'). +Alternatively, you can put separate macros in an `m4' subdirectory, and +put `ACLOCAL_AMFLAGS = -I m4' in your `Makefile.am' file so that the +`aclocal' program will be able to find them. + + The different macro prefixes indicate which tool defines the macro. +Macros which start with `AC_' are part of autoconf. Macros which start +with `AM_' are provided by automake or libtool. + + +File: configure.info, Node: Write Makefile.am, Next: Write acconfig.h, Prev: Write configure.in, Up: Getting Started + +2.2 Write Makefile.am +===================== + +You must write the file `Makefile.am'. This is an automake input file, +and the automake manual describes in detail what this file should look +like. + + The automake commands in `Makefile.am' mostly look like variable +assignments in a `Makefile'. automake recognizes special variable +names, and automatically add make rules to the output as needed. + + There will be one `Makefile.am' file for each directory in your +package. For each directory with subdirectories, the `Makefile.am' +file should contain the line + SUBDIRS = DIR DIR ... + where each DIR is the name of a subdirectory. + + For each `Makefile.am', there should be a corresponding `Makefile' +in the `AC_OUTPUT' macro in `configure.in'. + + Every `Makefile.am' written at Cygnus should contain the line + AUTOMAKE_OPTIONS = cygnus + This puts automake into Cygnus mode. See the automake manual for +details. + + You may to include the version number of `automake' that you are +using on the `AUTOMAKE_OPTIONS' line. For example, + AUTOMAKE_OPTIONS = cygnus 1.3 + This will prevent users from running an earlier version of +`automake' and perhaps getting an invalid `Makefile.in'. + + If your package builds a program, then in the directory where that +program is built you will normally want a line like + bin_PROGRAMS = PROGRAM + where PROGRAM is the name of the program. You will then want a line +like + PROGRAM_SOURCES = FILE FILE ... + where each FILE is the name of a source file to link into the +program (e.g., `foo.c'). + + If your package builds a library, and you do not want the library to +ever be built as a shared library, then in the directory where that +library is built you will normally want a line like + lib_LIBRARIES = libNAME.a + where `libNAME.a' is the name of the library. You will then want a +line like + libNAME_a_SOURCES = FILE FILE ... + where each FILE is the name of a source file to add to the library. + + If your package builds a library, and you want to permit building the +library as a shared library, then in the directory where that library is +built you will normally want a line like + lib_LTLIBRARIES = libNAME.la + The use of `LTLIBRARIES', and the `.la' extension, indicate a +library to be built using libtool. As usual, you will then want a line +like + libNAME_la_SOURCES = FILE FILE ... + + The strings `bin' and `lib' that appear above in `bin_PROGRAMS' and +`lib_LIBRARIES' are not arbitrary. They refer to particular +directories, which may be set by the `--bindir' and `--libdir' options +to `configure'. If those options are not used, the default values are +based on the `--prefix' or `--exec-prefix' options to `configure'. It +is possible to use other names if the program or library should be +installed in some other directory. + + The `Makefile.am' file may also contain almost anything that may +appear in a normal `Makefile'. automake also supports many other +special variables, as well as conditionals. + + See the automake manual for more information. + + +File: configure.info, Node: Write acconfig.h, Next: Generate files, Prev: Write Makefile.am, Up: Getting Started + +2.3 Write acconfig.h +==================== + +If you are generating a portability header file, (i.e., you are using +`AM_CONFIG_HEADER' in `configure.in'), then you will have to write a +`acconfig.h' file. It will have to contain the following lines. + + /* Name of package. */ + #undef PACKAGE + + /* Version of package. */ + #undef VERSION + + This requirement is really a bug in the system, and the requirement +may be eliminated at some later date. + + The `acconfig.h' file will also similar comment and `#undef' lines +for any unusual macros in the `configure.in' file, including any macro +which appears in a `AC_DEFINE' macro. + + In particular, if you are writing a GNU package and therefore include +`AC_DEFINE(_GNU_SOURCE)' in `configure.in' as suggested above, you will +need lines like this in `acconfig.h': + /* Enable GNU extensions. */ + #undef _GNU_SOURCE + + Normally the `autoheader' program will inform you of any such +requirements by printing an error message when it is run. However, if +you do anything particular odd in your `configure.in' file, you will +have to make sure that the right entries appear in `acconfig.h', since +otherwise the results of the tests may not be available in the +`config.h' file which your code will use. + + (Thee `PACKAGE' and `VERSION' lines are not required if you are not +using automake, and in that case you may not need a `acconfig.h' file +at all). + + +File: configure.info, Node: Generate files, Next: Getting Started Example, Prev: Write acconfig.h, Up: Getting Started + +2.4 Generate files +================== + +Once you have written `configure.in', `Makefile.am', `acconfig.h', and +possibly `acinclude.m4', you must use autoconf and automake programs to +produce the first versions of the generated files. This is done by +executing the following sequence of commands. + + aclocal + autoconf + autoheader + automake + + The `aclocal' and `automake' commands are part of the automake +package, and the `autoconf' and `autoheader' commands are part of the +autoconf package. + + If you are using a `m4' subdirectory for your macros, you will need +to use the `-I m4' option when you run `aclocal'. + + If you are not using the Cygnus tree, use the `-a' option when +running `automake' command in order to copy the required support files +into your source directory. + + If you are using libtool, you must build and install the libtool +package with the same `--prefix' and `--exec-prefix' options as you +used with the autoconf and automake packages. You must do this before +running any of the above commands. If you are not using the Cygnus +tree, you will need to run the `libtoolize' program to copy the libtool +support files into your directory. + + Once you have managed to run these commands without getting any +errors, you should create a new empty directory, and run the `configure' +script which will have been created by `autoconf' with the +`--enable-maintainer-mode' option. This will give you a set of +Makefiles which will include rules to automatically rebuild all the +generated files. + + After doing that, whenever you have changed some of the input files +and want to regenerated the other files, go to your object directory +and run `make'. Doing this is more reliable than trying to rebuild the +files manually, because there are complex order dependencies and it is +easy to forget something. + + +File: configure.info, Node: Getting Started Example, Prev: Generate files, Up: Getting Started + +2.5 Example +=========== + +Let's consider a trivial example. + + Suppose we want to write a simple version of `touch'. Our program, +which we will call `poke', will take a single file name argument, and +use the `utime' system call to set the modification and access times of +the file to the current time. We want this program to be highly +portable. + + We'll first see what this looks like without using autoconf and +automake, and then see what it looks like with them. + +* Menu: + +* Getting Started Example 1:: First Try. +* Getting Started Example 2:: Second Try. +* Getting Started Example 3:: Third Try. +* Generate Files in Example:: Generate Files. + + +File: configure.info, Node: Getting Started Example 1, Next: Getting Started Example 2, Up: Getting Started Example + +2.5.1 First Try +--------------- + +Here is our first try at `poke.c'. Note that we've written it without +ANSI/ISO C prototypes, since we want it to be highly portable. + + #include <stdio.h> + #include <stdlib.h> + #include <sys/types.h> + #include <utime.h> + + int + main (argc, argv) + int argc; + char **argv; + { + if (argc != 2) + { + fprintf (stderr, "Usage: poke file\n"); + exit (1); + } + + if (utime (argv[1], NULL) < 0) + { + perror ("utime"); + exit (1); + } + + exit (0); + } + + We also write a simple `Makefile'. + + CC = gcc + CFLAGS = -g -O2 + + all: poke + + poke: poke.o + $(CC) -o poke $(CFLAGS) $(LDFLAGS) poke.o + + So far, so good. + + Unfortunately, there are a few problems. + + On older Unix systems derived from BSD 4.3, the `utime' system call +does not accept a second argument of `NULL'. On those systems, we need +to pass a pointer to `struct utimbuf' structure. Unfortunately, even +older systems don't define that structure; on those systems, we need to +pass an array of two `long' values. + + The header file `stdlib.h' was invented by ANSI C, and older systems +don't have a copy. We included it above to get a declaration of `exit'. + + We can find some of these portability problems by running +`autoscan', which will create a `configure.scan' file which we can use +as a prototype for our `configure.in' file. I won't show the output, +but it will notice the potential problems with `utime' and `stdlib.h'. + + In our `Makefile', we don't provide any way to install the program. +This doesn't matter much for such a simple example, but a real program +will need an `install' target. For that matter, we will also want a +`clean' target. + + +File: configure.info, Node: Getting Started Example 2, Next: Getting Started Example 3, Prev: Getting Started Example 1, Up: Getting Started Example + +2.5.2 Second Try +---------------- + +Here is our second try at this program. + + We modify `poke.c' to use preprocessor macros to control what +features are available. (I've cheated a bit by using the same macro +names which autoconf will use). + + #include <stdio.h> + + #ifdef STDC_HEADERS + #include <stdlib.h> + #endif + + #include <sys/types.h> + + #ifdef HAVE_UTIME_H + #include <utime.h> + #endif + + #ifndef HAVE_UTIME_NULL + + #include <time.h> + + #ifndef HAVE_STRUCT_UTIMBUF + + struct utimbuf + { + long actime; + long modtime; + }; + + #endif + + static int + utime_now (file) + char *file; + { + struct utimbuf now; + + now.actime = now.modtime = time (NULL); + return utime (file, &now); + } + + #define utime(f, p) utime_now (f) + + #endif /* HAVE_UTIME_NULL */ + + int + main (argc, argv) + int argc; + char **argv; + { + if (argc != 2) + { + fprintf (stderr, "Usage: poke file\n"); + exit (1); + } + + if (utime (argv[1], NULL) < 0) + { + perror ("utime"); + exit (1); + } + + exit (0); + } + + Here is the associated `Makefile'. We've added support for the +preprocessor flags we use. We've also added `install' and `clean' +targets. + + # Set this to your installation directory. + bindir = /usr/local/bin + + # Uncomment this if you have the standard ANSI/ISO C header files. + # STDC_HDRS = -DSTDC_HEADERS + + # Uncomment this if you have utime.h. + # UTIME_H = -DHAVE_UTIME_H + + # Uncomment this if utime (FILE, NULL) works on your system. + # UTIME_NULL = -DHAVE_UTIME_NULL + + # Uncomment this if struct utimbuf is defined in utime.h. + # UTIMBUF = -DHAVE_STRUCT_UTIMBUF + + CC = gcc + CFLAGS = -g -O2 + + ALL_CFLAGS = $(STDC_HDRS) $(UTIME_H) $(UTIME_NULL) $(UTIMBUF) $(CFLAGS) + + all: poke + + poke: poke.o + $(CC) -o poke $(ALL_CFLAGS) $(LDFLAGS) poke.o + + .c.o: + $(CC) -c $(ALL_CFLAGS) poke.c + + install: poke + cp poke $(bindir)/poke + + clean: + rm poke poke.o + + Some problems with this approach should be clear. + + Users who want to compile poke will have to know how `utime' works +on their systems, so that they can uncomment the `Makefile' correctly. + + The installation is done using `cp', but many systems have an +`install' program which may be used, and which supports optional +features such as stripping debugging information out of the installed +binary. + + The use of `Makefile' variables like `CC', `CFLAGS' and `LDFLAGS' +follows the requirements of the GNU standards. This is convenient for +all packages, since it reduces surprises for users. However, it is +easy to get the details wrong, and wind up with a slightly nonstandard +distribution. + + +File: configure.info, Node: Getting Started Example 3, Next: Generate Files in Example, Prev: Getting Started Example 2, Up: Getting Started Example + +2.5.3 Third Try +--------------- + +For our third try at this program, we will write a `configure.in' +script to discover the configuration features on the host system, rather +than requiring the user to edit the `Makefile'. We will also write a +`Makefile.am' rather than a `Makefile'. + + The only change to `poke.c' is to add a line at the start of the +file: + #include "config.h" + + The new `configure.in' file is as follows. + + AC_INIT(poke.c) + AM_INIT_AUTOMAKE(poke, 1.0) + AM_CONFIG_HEADER(config.h:config.in) + AC_PROG_CC + AC_HEADER_STDC + AC_CHECK_HEADERS(utime.h) + AC_EGREP_HEADER(utimbuf, utime.h, AC_DEFINE(HAVE_STRUCT_UTIMBUF)) + AC_FUNC_UTIME_NULL + AC_OUTPUT(Makefile) + + The first four macros in this file, and the last one, were described +above; see *Note Write configure.in::. If we omit these macros, then +when we run `automake' we will get a reminder that we need them. + + The other macros are standard autoconf macros. + +`AC_HEADER_STDC' + Check for standard C headers. + +`AC_CHECK_HEADERS' + Check whether a particular header file exists. + +`AC_EGREP_HEADER' + Check for a particular string in a particular header file, in this + case checking for `utimbuf' in `utime.h'. + +`AC_FUNC_UTIME_NULL' + Check whether `utime' accepts a NULL second argument to set the + file change time to the current time. + + See the autoconf manual for a more complete description. + + The new `Makefile.am' file is as follows. Note how simple this is +compared to our earlier `Makefile'. + + bin_PROGRAMS = poke + + poke_SOURCES = poke.c + + This means that we should build a single program name `poke'. It +should be installed in the binary directory, which we called `bindir' +earlier. The program `poke' is built from the source file `poke.c'. + + We must also write a `acconfig.h' file. Besides `PACKAGE' and +`VERSION', which must be mentioned for all packages which use automake, +we must include `HAVE_STRUCT_UTIMBUF', since we mentioned it in an +`AC_DEFINE'. + + /* Name of package. */ + #undef PACKAGE + + /* Version of package. */ + #undef VERSION + + /* Whether utime.h defines struct utimbuf. */ + #undef HAVE_STRUCT_UTIMBUF + + +File: configure.info, Node: Generate Files in Example, Prev: Getting Started Example 3, Up: Getting Started Example + +2.5.4 Generate Files +-------------------- + +We must now generate the other files, using the following commands. + + aclocal + autoconf + autoheader + automake + + When we run `autoheader', it will remind us of any macros we forgot +to add to `acconfig.h'. + + When we run `automake', it will want to add some files to our +distribution. It will add them automatically if we use the +`--add-missing' option. + + By default, `automake' will run in GNU mode, which means that it +will want us to create certain additional files; as of this writing, it +will want `NEWS', `README', `AUTHORS', and `ChangeLog', all of which +are files which should appear in a standard GNU distribution. We can +either add those files, or run `automake' with the `--foreign' option. + + Running these tools will generate the following files, all of which +are described in the next chapter. + + * `aclocal.m4' + + * `configure' + + * `config.in' + + * `Makefile.in' + + * `stamp-h.in' + + +File: configure.info, Node: Files, Next: Configuration Names, Prev: Getting Started, Up: Top + +3 Files +******* + +As was seen in the previous chapter, the GNU configure and build system +uses a number of different files. The developer must write a few files. +The others are generated by various tools. + + The system is rather flexible, and can be used in many different +ways. In describing the files that it uses, I will describe the common +case, and mention some other cases that may arise. + +* Menu: + +* Developer Files:: Developer Files. +* Build Files:: Build Files. +* Support Files:: Support Files. + + +File: configure.info, Node: Developer Files, Next: Build Files, Up: Files + +3.1 Developer Files +=================== + +This section describes the files written or generated by the developer +of a package. + +* Menu: + +* Developer Files Picture:: Developer Files Picture. +* Written Developer Files:: Written Developer Files. +* Generated Developer Files:: Generated Developer Files. + + +File: configure.info, Node: Developer Files Picture, Next: Written Developer Files, Up: Developer Files + +3.1.1 Developer Files Picture +----------------------------- + +Here is a picture of the files which are written by the developer, the +generated files which would be included with a complete source +distribution, and the tools which create those files. The file names +are plain text and the tool names are enclosed by `*' characters (e.g., +`autoheader' is the name of a tool, not the name of a file). + + acconfig.h configure.in Makefile.am + | | | + | --------------+---------------------- | + | | | | | + v v | acinclude.m4 | | + *autoheader* | | v v + | | v --->*automake* + v |--->*aclocal* | | + config.in | | | v + | v | Makefile.in + | aclocal.m4--- + | | + v v + *autoconf* + | + v + configure + + +File: configure.info, Node: Written Developer Files, Next: Generated Developer Files, Prev: Developer Files Picture, Up: Developer Files + +3.1.2 Written Developer Files +----------------------------- + +The following files would be written by the developer. + +`configure.in' + This is the configuration script. This script contains + invocations of autoconf macros. It may also contain ordinary + shell script code. This file will contain feature tests for + portability issues. The last thing in the file will normally be + an `AC_OUTPUT' macro listing which files to create when the + builder runs the configure script. This file is always required + when using the GNU configure system. *Note Write configure.in::. + +`Makefile.am' + This is the automake input file. It describes how the code should + be built. It consists of definitions of automake variables. It + may also contain ordinary Makefile targets. This file is only + needed when using automake (newer tools normally use automake, but + there are still older tools which have not been converted, in + which the developer writes `Makefile.in' directly). *Note Write + Makefile.am::. + +`acconfig.h' + When the configure script creates a portability header file, by + using `AM_CONFIG_HEADER' (or, if not using automake, + `AC_CONFIG_HEADER'), this file is used to describe macros which are + not recognized by the `autoheader' command. This is normally a + fairly uninteresting file, consisting of a collection of `#undef' + lines with comments. Normally any call to `AC_DEFINE' in + `configure.in' will require a line in this file. *Note Write + acconfig.h::. + +`acinclude.m4' + This file is not always required. It defines local autoconf + macros. These macros may then be used in `configure.in'. If you + don't need any local autoconf macros, then you don't need this + file at all. In fact, in general, you never need local autoconf + macros, since you can put everything in `configure.in', but + sometimes a local macro is convenient. + + Newer tools may omit `acinclude.m4', and instead use a + subdirectory, typically named `m4', and define `ACLOCAL_AMFLAGS = + -I m4' in `Makefile.am' to force `aclocal' to look there for macro + definitions. The macro definitions are then placed in separate + files in that directory. + + The `acinclude.m4' file is only used when using automake; in older + tools, the developer writes `aclocal.m4' directly, if it is needed. + + +File: configure.info, Node: Generated Developer Files, Prev: Written Developer Files, Up: Developer Files + +3.1.3 Generated Developer Files +------------------------------- + +The following files would be generated by the developer. + + When using automake, these files are normally not generated manually +after the first time. Instead, the generated `Makefile' contains rules +to automatically rebuild the files as required. When +`AM_MAINTAINER_MODE' is used in `configure.in' (the normal case in +Cygnus code), the automatic rebuilding rules will only be defined if +you configure using the `--enable-maintainer-mode' option. + + When using automatic rebuilding, it is important to ensure that all +the various tools have been built and installed on your `PATH'. Using +automatic rebuilding is highly recommended, so much so that I'm not +going to explain what you have to do if you don't use it. + +`configure' + This is the configure script which will be run when building the + package. This is generated by `autoconf' from `configure.in' and + `aclocal.m4'. This is a shell script. + +`Makefile.in' + This is the file which the configure script will turn into the + `Makefile' at build time. This file is generated by `automake' + from `Makefile.am'. If you aren't using automake, you must write + this file yourself. This file is pretty much a normal `Makefile', + with some configure substitutions for certain variables. + +`aclocal.m4' + This file is created by the `aclocal' program, based on the + contents of `configure.in' and `acinclude.m4' (or, as noted in the + description of `acinclude.m4' above, on the contents of an `m4' + subdirectory). This file contains definitions of autoconf macros + which `autoconf' will use when generating the file `configure'. + These autoconf macros may be defined by you in `acinclude.m4' or + they may be defined by other packages such as automake, libtool or + gettext. If you aren't using automake, you will normally write + this file yourself; in that case, if `configure.in' uses only + standard autoconf macros, this file will not be needed at all. + +`config.in' + This file is created by `autoheader' based on `acconfig.h' and + `configure.in'. At build time, the configure script will define + some of the macros in it to create `config.h', which may then be + included by your program. This permits your C code to use + preprocessor conditionals to change its behaviour based on the + characteristics of the host system. This file may also be called + `config.h.in'. + +`stamp.h-in' + This rather uninteresting file, which I omitted from the picture, + is generated by `automake'. It always contains the string + `timestamp'. It is used as a timestamp file indicating whether + `config.in' is up to date. Using a timestamp file means that + `config.in' can be marked as up to date without actually changing + its modification time. This is useful since `config.in' depends + upon `configure.in', but it is easy to change `configure.in' in a + way which does not affect `config.in'. + + +File: configure.info, Node: Build Files, Next: Support Files, Prev: Developer Files, Up: Files + +3.2 Build Files +=============== + +This section describes the files which are created at configure and +build time. These are the files which somebody who builds the package +will see. + + Of course, the developer will also build the package. The +distinction between developer files and build files is not that the +developer does not see the build files, but that somebody who only +builds the package does not have to worry about the developer files. + +* Menu: + +* Build Files Picture:: Build Files Picture. +* Build Files Description:: Build Files Description. + + +File: configure.info, Node: Build Files Picture, Next: Build Files Description, Up: Build Files + +3.2.1 Build Files Picture +------------------------- + +Here is a picture of the files which will be created at build time. +`config.status' is both a created file and a shell script which is run +to create other files, and the picture attempts to show that. + + config.in *configure* Makefile.in + | | | + | v | + | config.status | + | | | + *config.status*<======+==========>*config.status* + | | + v v + config.h Makefile + + +File: configure.info, Node: Build Files Description, Prev: Build Files Picture, Up: Build Files + +3.2.2 Build Files Description +----------------------------- + +This is a description of the files which are created at build time. + +`config.status' + The first step in building a package is to run the `configure' + script. The `configure' script will create the file + `config.status', which is itself a shell script. When you first + run `configure', it will automatically run `config.status'. An + `Makefile' derived from an automake generated `Makefile.in' will + contain rules to automatically run `config.status' again when + necessary to recreate certain files if their inputs change. + +`Makefile' + This is the file which make will read to build the program. The + `config.status' script will transform `Makefile.in' into + `Makefile'. + +`config.h' + This file defines C preprocessor macros which C code can use to + adjust its behaviour on different systems. The `config.status' + script will transform `config.in' into `config.h'. + +`config.cache' + This file did not fit neatly into the picture, and I omitted it. + It is used by the `configure' script to cache results between + runs. This can be an important speedup. If you modify + `configure.in' in such a way that the results of old tests should + change (perhaps you have added a new library to `LDFLAGS'), then + you will have to remove `config.cache' to force the tests to be + rerun. + + The autoconf manual explains how to set up a site specific cache + file. This can speed up running `configure' scripts on your + system. + +`stamp.h' + This file, which I omitted from the picture, is similar to + `stamp-h.in'. It is used as a timestamp file indicating whether + `config.h' is up to date. This is useful since `config.h' depends + upon `config.status', but it is easy for `config.status' to change + in a way which does not affect `config.h'. + + +File: configure.info, Node: Support Files, Prev: Build Files, Up: Files + +3.3 Support Files +================= + +The GNU configure and build system requires several support files to be +included with your distribution. You do not normally need to concern +yourself with these. If you are using the Cygnus tree, most are already +present. Otherwise, they will be installed with your source by +`automake' (with the `--add-missing' option) and `libtoolize'. + + You don't have to put the support files in the top level directory. +You can put them in a subdirectory, and use the `AC_CONFIG_AUX_DIR' +macro in `configure.in' to tell `automake' and the `configure' script +where they are. + + In this section, I describe the support files, so that you can know +what they are and why they are there. + +`ABOUT-NLS' + Added by automake if you are using gettext. This is a + documentation file about the gettext project. + +`ansi2knr.c' + Used by an automake generated `Makefile' if you put `ansi2knr' in + `AUTOMAKE_OPTIONS' in `Makefile.am'. This permits compiling ANSI + C code with a K&R C compiler. + +`ansi2knr.1' + The man page which goes with `ansi2knr.c'. + +`config.guess' + A shell script which determines the configuration name for the + system on which it is run. + +`config.sub' + A shell script which canonicalizes a configuration name entered by + a user. + +`elisp-comp' + Used to compile Emacs LISP files. + +`install-sh' + A shell script which installs a program. This is used if the + configure script can not find an install binary. + +`ltconfig' + Used by libtool. This is a shell script which configures libtool + for the particular system on which it is used. + +`ltmain.sh' + Used by libtool. This is the actual libtool script which is used, + after it is configured by `ltconfig' to build a library. + +`mdate-sh' + A shell script used by an automake generated `Makefile' to pretty + print the modification time of a file. This is used to maintain + version numbers for texinfo files. + +`missing' + A shell script used if some tool is missing entirely. This is + used by an automake generated `Makefile' to avoid certain sorts of + timestamp problems. + +`mkinstalldirs' + A shell script which creates a directory, including all parent + directories. This is used by an automake generated `Makefile' + during installation. + +`texinfo.tex' + Required if you have any texinfo files. This is used when + converting Texinfo files into DVI using `texi2dvi' and TeX. + +`ylwrap' + A shell script used by an automake generated `Makefile' to run + programs like `bison', `yacc', `flex', and `lex'. These programs + default to producing output files with a fixed name, and the + `ylwrap' script runs them in a subdirectory to avoid file name + conflicts when using a parallel make program. + + +File: configure.info, Node: Configuration Names, Next: Cross Compilation Tools, Prev: Files, Up: Top + +4 Configuration Names +********************* + +The GNU configure system names all systems using a "configuration +name". All such names used to be triplets (they may now contain four +parts in certain cases), and the term "configuration triplet" is still +seen. + +* Menu: + +* Configuration Name Definition:: Configuration Name Definition. +* Using Configuration Names:: Using Configuration Names. + + +File: configure.info, Node: Configuration Name Definition, Next: Using Configuration Names, Up: Configuration Names + +4.1 Configuration Name Definition +================================= + +This is a string of the form CPU-MANUFACTURER-OPERATING_SYSTEM. In +some cases, this is extended to a four part form: +CPU-MANUFACTURER-KERNEL-OPERATING_SYSTEM. + + When using a configuration name in a configure option, it is normally +not necessary to specify an entire name. In particular, the +MANUFACTURER field is often omitted, leading to strings such as +`i386-linux' or `sparc-sunos'. The shell script `config.sub' will +translate these shortened strings into the canonical form. autoconf +will arrange for `config.sub' to be run automatically when it is needed. + + The fields of a configuration name are as follows: + +CPU + The type of processor. This is typically something like `i386' or + `sparc'. More specific variants are used as well, such as + `mipsel' to indicate a little endian MIPS processor. + +MANUFACTURER + A somewhat freeform field which indicates the manufacturer of the + system. This is often simply `unknown'. Other common strings are + `pc' for an IBM PC compatible system, or the name of a workstation + vendor, such as `sun'. + +OPERATING_SYSTEM + The name of the operating system which is run on the system. This + will be something like `solaris2.5' or `irix6.3'. There is no + particular restriction on the version number, and strings like + `aix4.1.4.0' are seen. For an embedded system, which has no + operating system, this field normally indicates the type of object + file format, such as `elf' or `coff'. + +KERNEL + This is used mainly for GNU/Linux. A typical GNU/Linux + configuration name is `i586-pc-linux-gnulibc1'. In this case the + kernel, `linux', is separated from the operating system, + `gnulibc1'. + + The shell script `config.guess' will normally print the correct +configuration name for the system on which it is run. It does by +running `uname' and by examining other characteristics of the system. + + Because `config.guess' can normally determine the configuration name +for a machine, it is normally only necessary to specify a configuration +name when building a cross-compiler or when building using a +cross-compiler. + + +File: configure.info, Node: Using Configuration Names, Prev: Configuration Name Definition, Up: Configuration Names + +4.2 Using Configuration Names +============================= + +A configure script will sometimes have to make a decision based on a +configuration name. You will need to do this if you have to compile +code differently based on something which can not be tested using a +standard autoconf feature test. + + It is normally better to test for particular features, rather than to +test for a particular system. This is because as Unix evolves, +different systems copy features from one another. Even if you need to +determine whether the feature is supported based on a configuration +name, you should define a macro which describes the feature, rather than +defining a macro which describes the particular system you are on. + + Testing for a particular system is normally done using a case +statement in `configure.in'. The case statement might look something +like the following, assuming that `host' is a shell variable holding a +canonical configuration name (which will be the case if `configure.in' +uses the `AC_CANONICAL_HOST' or `AC_CANONICAL_SYSTEM' macro). + + case "${host}" in + i[3-7]86-*-linux-gnu*) do something ;; + sparc*-sun-solaris2.[56789]*) do something ;; + sparc*-sun-solaris*) do something ;; + mips*-*-elf*) do something ;; + esac + + It is particularly important to use `*' after the operating system +field, in order to match the version number which will be generated by +`config.guess'. + + In most cases you must be careful to match a range of processor +types. For most processor families, a trailing `*' suffices, as in +`mips*' above. For the i386 family, something along the lines of +`i[3-7]86' suffices at present. For the m68k family, you will need +something like `m68*'. Of course, if you do not need to match on the +processor, it is simpler to just replace the entire field by a `*', as +in `*-*-irix*'. + + +File: configure.info, Node: Cross Compilation Tools, Next: Canadian Cross, Prev: Configuration Names, Up: Top + +5 Cross Compilation Tools +************************* + +The GNU configure and build system can be used to build "cross +compilation" tools. A cross compilation tool is a tool which runs on +one system and produces code which runs on another system. + +* Menu: + +* Cross Compilation Concepts:: Cross Compilation Concepts. +* Host and Target:: Host and Target. +* Using the Host Type:: Using the Host Type. +* Specifying the Target:: Specifying the Target. +* Using the Target Type:: Using the Target Type. +* Cross Tools in the Cygnus Tree:: Cross Tools in the Cygnus Tree + + +File: configure.info, Node: Cross Compilation Concepts, Next: Host and Target, Up: Cross Compilation Tools + +5.1 Cross Compilation Concepts +============================== + +A compiler which produces programs which run on a different system is a +cross compilation compiler, or simply a "cross compiler". Similarly, +we speak of cross assemblers, cross linkers, etc. + + In the normal case, a compiler produces code which runs on the same +system as the one on which the compiler runs. When it is necessary to +distinguish this case from the cross compilation case, such a compiler +is called a "native compiler". Similarly, we speak of native +assemblers, etc. + + Although the debugger is not strictly speaking a compilation tool, +it is nevertheless meaningful to speak of a cross debugger: a debugger +which is used to debug code which runs on another system. Everything +that is said below about configuring cross compilation tools applies to +the debugger as well. + + +File: configure.info, Node: Host and Target, Next: Using the Host Type, Prev: Cross Compilation Concepts, Up: Cross Compilation Tools + +5.2 Host and Target +=================== + +When building cross compilation tools, there are two different systems +involved: the system on which the tools will run, and the system for +which the tools generate code. + + The system on which the tools will run is called the "host" system. + + The system for which the tools generate code is called the "target" +system. + + For example, suppose you have a compiler which runs on a GNU/Linux +system and generates ELF programs for a MIPS embedded system. In this +case the GNU/Linux system is the host, and the MIPS ELF system is the +target. Such a compiler could be called a GNU/Linux cross MIPS ELF +compiler, or, equivalently, a `i386-linux-gnu' cross `mips-elf' +compiler. + + Naturally, most programs are not cross compilation tools. For those +programs, it does not make sense to speak of a target. It only makes +sense to speak of a target for tools like `gcc' or the `binutils' which +actually produce running code. For example, it does not make sense to +speak of the target of a tool like `bison' or `make'. + + Most cross compilation tools can also serve as native tools. For a +native compilation tool, it is still meaningful to speak of a target. +For a native tool, the target is the same as the host. For example, for +a GNU/Linux native compiler, the host is GNU/Linux, and the target is +also GNU/Linux. + + +File: configure.info, Node: Using the Host Type, Next: Specifying the Target, Prev: Host and Target, Up: Cross Compilation Tools + +5.3 Using the Host Type +======================= + +In almost all cases the host system is the system on which you run the +`configure' script, and on which you build the tools (for the case when +they differ, *note Canadian Cross::). + + If your configure script needs to know the configuration name of the +host system, and the package is not a cross compilation tool and +therefore does not have a target, put `AC_CANONICAL_HOST' in +`configure.in'. This macro will arrange to define a few shell +variables when the `configure' script is run. + +`host' + The canonical configuration name of the host. This will normally + be determined by running the `config.guess' shell script, although + the user is permitted to override this by using an explicit + `--host' option. + +`host_alias' + In the unusual case that the user used an explicit `--host' option, + this will be the argument to `--host'. In the normal case, this + will be the same as the `host' variable. + +`host_cpu' +`host_vendor' +`host_os' + The first three parts of the canonical configuration name. + + The shell variables may be used by putting shell code in +`configure.in'. For an example, see *Note Using Configuration Names::. + + +File: configure.info, Node: Specifying the Target, Next: Using the Target Type, Prev: Using the Host Type, Up: Cross Compilation Tools + +5.4 Specifying the Target +========================= + +By default, the `configure' script will assume that the target is the +same as the host. This is the more common case; for example, it leads +to a native compiler rather than a cross compiler. + + If you want to build a cross compilation tool, you must specify the +target explicitly by using the `--target' option when you run +`configure'. The argument to `--target' is the configuration name of +the system for which you wish to generate code. *Note Configuration +Names::. + + For example, to build tools which generate code for a MIPS ELF +embedded system, you would use `--target mips-elf'. + + +File: configure.info, Node: Using the Target Type, Next: Cross Tools in the Cygnus Tree, Prev: Specifying the Target, Up: Cross Compilation Tools + +5.5 Using the Target Type +========================= + +When writing `configure.in' for a cross compilation tool, you will need +to use information about the target. To do this, put +`AC_CANONICAL_SYSTEM' in `configure.in'. + + `AC_CANONICAL_SYSTEM' will look for a `--target' option and +canonicalize it using the `config.sub' shell script. It will also run +`AC_CANONICAL_HOST' (*note Using the Host Type::). + + The target type will be recorded in the following shell variables. +Note that the host versions of these variables will also be defined by +`AC_CANONICAL_HOST'. + +`target' + The canonical configuration name of the target. + +`target_alias' + The argument to the `--target' option. If the user did not specify + a `--target' option, this will be the same as `host_alias'. + +`target_cpu' +`target_vendor' +`target_os' + The first three parts of the canonical target configuration name. + + Note that if `host' and `target' are the same string, you can assume +a native configuration. If they are different, you can assume a cross +configuration. + + It is arguably possible for `host' and `target' to represent the +same system, but for the strings to not be identical. For example, if +`config.guess' returns `sparc-sun-sunos4.1.4', and somebody configures +with `--target sparc-sun-sunos4.1', then the slight differences between +the two versions of SunOS may be unimportant for your tool. However, +in the general case it can be quite difficult to determine whether the +differences between two configuration names are significant or not. +Therefore, by convention, if the user specifies a `--target' option +without specifying a `--host' option, it is assumed that the user wants +to configure a cross compilation tool. + + The variables `target' and `target_alias' should be handled +differently. + + In general, whenever the user may actually see a string, +`target_alias' should be used. This includes anything which may appear +in the file system, such as a directory name or part of a tool name. +It also includes any tool output, unless it is clearly labelled as the +canonical target configuration name. This permits the user to use the +`--target' option to specify how the tool will appear to the outside +world. + + On the other hand, when checking for characteristics of the target +system, `target' should be used. This is because a wide variety of +`--target' options may map into the same canonical configuration name. +You should not attempt to duplicate the canonicalization done by +`config.sub' in your own code. + + By convention, cross tools are installed with a prefix of the +argument used with the `--target' option, also known as `target_alias' +(*note Using the Target Type::). If the user does not use the +`--target' option, and thus is building a native tool, no prefix is +used. + + For example, if gcc is configured with `--target mips-elf', then the +installed binary will be named `mips-elf-gcc'. If gcc is configured +without a `--target' option, then the installed binary will be named +`gcc'. + + The autoconf macro `AC_ARG_PROGRAM' will handle this for you. If +you are using automake, no more need be done; the programs will +automatically be installed with the correct prefixes. Otherwise, see +the autoconf documentation for `AC_ARG_PROGRAM'. + + +File: configure.info, Node: Cross Tools in the Cygnus Tree, Prev: Using the Target Type, Up: Cross Compilation Tools + +5.6 Cross Tools in the Cygnus Tree +================================== + +The Cygnus tree is used for various packages including gdb, the GNU +binutils, and egcs. It is also, of course, used for Cygnus releases. + + In the Cygnus tree, the top level `configure' script uses the old +Cygnus configure system, not autoconf. The top level `Makefile.in' is +written to build packages based on what is in the source tree, and +supports building a large number of tools in a single +`configure'/`make' step. + + The Cygnus tree may be configured with a `--target' option. The +`--target' option applies recursively to every subdirectory, and +permits building an entire set of cross tools at once. + +* Menu: + +* Host and Target Libraries:: Host and Target Libraries. +* Target Library Configure Scripts:: Target Library Configure Scripts. +* Make Targets in Cygnus Tree:: Make Targets in Cygnus Tree. +* Target libiberty:: Target libiberty + + +File: configure.info, Node: Host and Target Libraries, Next: Target Library Configure Scripts, Up: Cross Tools in the Cygnus Tree + +5.6.1 Host and Target Libraries +------------------------------- + +The Cygnus tree distinguishes host libraries from target libraries. + + Host libraries are built with the compiler used to build the programs +which run on the host, which is called the host compiler. This includes +libraries such as `bfd' and `tcl'. These libraries are built with the +host compiler, and are linked into programs like the binutils or gcc +which run on the host. + + Target libraries are built with the target compiler. If gcc is +present in the source tree, then the target compiler is the gcc that is +built using the host compiler. Target libraries are libraries such as +`newlib' and `libstdc++'. These libraries are not linked into the host +programs, but are instead made available for use with programs built +with the target compiler. + + For the rest of this section, assume that gcc is present in the +source tree, so that it will be used to build the target libraries. + + There is a complication here. The configure process needs to know +which compiler you are going to use to build a tool; otherwise, the +feature tests will not work correctly. The Cygnus tree handles this by +not configuring the target libraries until the target compiler is +built. In order to permit everything to build using a single +`configure'/`make', the configuration of the target libraries is +actually triggered during the make step. + + When the target libraries are configured, the `--target' option is +not used. Instead, the `--host' option is used with the argument of +the `--target' option for the overall configuration. If no `--target' +option was used for the overall configuration, the `--host' option will +be passed with the output of the `config.guess' shell script. Any +`--build' option is passed down unchanged. + + This translation of configuration options is done because since the +target libraries are compiled with the target compiler, they are being +built in order to run on the target of the overall configuration. By +the definition of host, this means that their host system is the same as +the target system of the overall configuration. + + The same process is used for both a native configuration and a cross +configuration. Even when using a native configuration, the target +libraries will be configured and built using the newly built compiler. +This is particularly important for the C++ libraries, since there is no +reason to assume that the C++ compiler used to build the host tools (if +there even is one) uses the same ABI as the g++ compiler which will be +used to build the target libraries. + + There is one difference between a native configuration and a cross +configuration. In a native configuration, the target libraries are +normally configured and built as siblings of the host tools. In a cross +configuration, the target libraries are normally built in a subdirectory +whose name is the argument to `--target'. This is mainly for +historical reasons. + + To summarize, running `configure' in the Cygnus tree configures all +the host libraries and tools, but does not configure any of the target +libraries. Running `make' then does the following steps: + + * Build the host libraries. + + * Build the host programs, including gcc. Note that we call gcc + both a host program (since it runs on the host) and a target + compiler (since it generates code for the target). + + * Using the newly built target compiler, configure the target + libraries. + + * Build the target libraries. + + The steps need not be done in precisely this order, since they are +actually controlled by `Makefile' targets. + + +File: configure.info, Node: Target Library Configure Scripts, Next: Make Targets in Cygnus Tree, Prev: Host and Target Libraries, Up: Cross Tools in the Cygnus Tree + +5.6.2 Target Library Configure Scripts +-------------------------------------- + +There are a few things you must know in order to write a configure +script for a target library. This is just a quick sketch, and beginners +shouldn't worry if they don't follow everything here. + + The target libraries are configured and built using a newly built +target compiler. There may not be any startup files or libraries for +this target compiler. In fact, those files will probably be built as +part of some target library, which naturally means that they will not +exist when your target library is configured. + + This means that the configure script for a target library may not use +any test which requires doing a link. This unfortunately includes many +useful autoconf macros, such as `AC_CHECK_FUNCS'. autoconf macros +which do a compile but not a link, such as `AC_CHECK_HEADERS', may be +used. + + This is a severe restriction, but normally not a fatal one, as target +libraries can often assume the presence of other target libraries, and +thus know which functions will be available. + + As of this writing, the autoconf macro `AC_PROG_CC' does a link to +make sure that the compiler works. This may fail in a target library, +so target libraries must use a different set of macros to locate the +compiler. See the `configure.in' file in a directory like `libiberty' +or `libgloss' for an example. + + As noted in the previous section, target libraries are sometimes +built in directories which are siblings to the host tools, and are +sometimes built in a subdirectory. The `--with-target-subdir' configure +option will be passed when the library is configured. Its value will be +an empty string if the target library is a sibling. Its value will be +the name of the subdirectory if the target library is in a subdirectory. + + If the overall build is not a native build (i.e., the overall +configure used the `--target' option), then the library will be +configured with the `--with-cross-host' option. The value of this +option will be the host system of the overall build. Recall that the +host system of the library will be the target of the overall build. If +the overall build is a native build, the `--with-cross-host' option +will not be used. + + A library which can be built both standalone and as a target library +may want to install itself into different directories depending upon the +case. When built standalone, or when built native, the library should +be installed in `$(libdir)'. When built as a target library which is +not native, the library should be installed in `$(tooldir)/lib'. The +`--with-cross-host' option may be used to distinguish these cases. + + This same test of `--with-cross-host' may be used to see whether it +is OK to use link tests in the configure script. If the +`--with-cross-host' option is not used, then the library is being built +either standalone or native, and a link should work. + + +File: configure.info, Node: Make Targets in Cygnus Tree, Next: Target libiberty, Prev: Target Library Configure Scripts, Up: Cross Tools in the Cygnus Tree + +5.6.3 Make Targets in Cygnus Tree +--------------------------------- + +The top level `Makefile' in the Cygnus tree defines targets for every +known subdirectory. + + For every subdirectory DIR which holds a host library or program, +the `Makefile' target `all-DIR' will build that library or program. + + There are dependencies among host tools. For example, building gcc +requires first building gas, because the gcc build process invokes the +target assembler. These dependencies are reflected in the top level +`Makefile'. + + For every subdirectory DIR which holds a target library, the +`Makefile' target `configure-target-DIR' will configure that library. +The `Makefile' target `all-target-DIR' will build that library. + + Every `configure-target-DIR' target depends upon `all-gcc', since +gcc, the target compiler, is required to configure the tool. Every +`all-target-DIR' target depends upon the corresponding +`configure-target-DIR' target. + + There are several other targets which may be of interest for each +directory: `install-DIR', `clean-DIR', and `check-DIR'. There are also +corresponding `target' versions of these for the target libraries , +such as `install-target-DIR'. + + +File: configure.info, Node: Target libiberty, Prev: Make Targets in Cygnus Tree, Up: Cross Tools in the Cygnus Tree + +5.6.4 Target libiberty +---------------------- + +The `libiberty' subdirectory is currently a special case, in that it is +the only directory which is built both using the host compiler and +using the target compiler. + + This is because the files in `libiberty' are used when building the +host tools, and they are also incorporated into the `libstdc++' target +library as support code. + + This duality does not pose any particular difficulties. It means +that there are targets for both `all-libiberty' and +`all-target-libiberty'. + + In a native configuration, when target libraries are not built in a +subdirectory, the same objects are normally used as both the host build +and the target build. This is normally OK, since libiberty contains +only C code, and in a native configuration the results of the host +compiler and the target compiler are normally interoperable. + + Irix 6 is again an exception here, since the SGI native compiler +defaults to using the `O32' ABI, and gcc defaults to using the `N32' +ABI. On Irix 6, the target libraries are built in a subdirectory even +for a native configuration, avoiding this problem. + + There are currently no other libraries built for both the host and +the target, but there is no conceptual problem with adding more. + + +File: configure.info, Node: Canadian Cross, Next: Cygnus Configure, Prev: Cross Compilation Tools, Up: Top + +6 Canadian Cross +**************** + +It is possible to use the GNU configure and build system to build a +program which will run on a system which is different from the system on +which the tools are built. In other words, it is possible to build +programs using a cross compiler. + + This is referred to as a "Canadian Cross". + +* Menu: + +* Canadian Cross Example:: Canadian Cross Example. +* Canadian Cross Concepts:: Canadian Cross Concepts. +* Build Cross Host Tools:: Build Cross Host Tools. +* Build and Host Options:: Build and Host Options. +* CCross not in Cygnus Tree:: Canadian Cross not in Cygnus Tree. +* CCross in Cygnus Tree:: Canadian Cross in Cygnus Tree. +* Supporting Canadian Cross:: Supporting Canadian Cross. + + +File: configure.info, Node: Canadian Cross Example, Next: Canadian Cross Concepts, Up: Canadian Cross + +6.1 Canadian Cross Example +========================== + +Here is an example of a Canadian Cross. + + While running on a GNU/Linux, you can build a program which will run +on a Solaris system. You would use a GNU/Linux cross Solaris compiler +to build the program. + + Of course, you could not run the resulting program on your GNU/Linux +system. You would have to copy it over to a Solaris system before you +would run it. + + Of course, you could also simply build the programs on the Solaris +system in the first place. However, perhaps the Solaris system is not +available for some reason; perhaps you actually don't have one, but you +want to build the tools for somebody else to use. Or perhaps your +GNU/Linux system is much faster than your Solaris system. + + A Canadian Cross build is most frequently used when building +programs to run on a non-Unix system, such as DOS or Windows. It may +be simpler to configure and build on a Unix system than to support the +configuration machinery on a non-Unix system. + + +File: configure.info, Node: Canadian Cross Concepts, Next: Build Cross Host Tools, Prev: Canadian Cross Example, Up: Canadian Cross + +6.2 Canadian Cross Concepts +=========================== + +When building a Canadian Cross, there are at least two different systems +involved: the system on which the tools are being built, and the system +on which the tools will run. + + The system on which the tools are being built is called the "build" +system. + + The system on which the tools will run is called the host system. + + For example, if you are building a Solaris program on a GNU/Linux +system, as in the previous section, the build system would be GNU/Linux, +and the host system would be Solaris. + + It is, of course, possible to build a cross compiler using a Canadian +Cross (i.e., build a cross compiler using a cross compiler). In this +case, the system for which the resulting cross compiler generates code +is called the target system. (For a more complete discussion of host +and target systems, *note Host and Target::). + + An example of building a cross compiler using a Canadian Cross would +be building a Windows cross MIPS ELF compiler on a GNU/Linux system. In +this case the build system would be GNU/Linux, the host system would be +Windows, and the target system would be MIPS ELF. + + The name Canadian Cross comes from the case when the build, host, and +target systems are all different. At the time that these issues were +all being hashed out, Canada had three national political parties. + + +File: configure.info, Node: Build Cross Host Tools, Next: Build and Host Options, Prev: Canadian Cross Concepts, Up: Canadian Cross + +6.3 Build Cross Host Tools +========================== + +In order to configure a program for a Canadian Cross build, you must +first build and install the set of cross tools you will use to build the +program. + + These tools will be build cross host tools. That is, they will run +on the build system, and will produce code that runs on the host system. + + It is easy to confuse the meaning of build and host here. Always +remember that the build system is where you are doing the build, and the +host system is where the resulting program will run. Therefore, you +need a build cross host compiler. + + In general, you must have a complete cross environment in order to do +the build. This normally means a cross compiler, cross assembler, and +so forth, as well as libraries and include files for the host system. + + +File: configure.info, Node: Build and Host Options, Next: CCross not in Cygnus Tree, Prev: Build Cross Host Tools, Up: Canadian Cross + +6.4 Build and Host Options +========================== + +When you run `configure', you must use both the `--build' and `--host' +options. + + The `--build' option is used to specify the configuration name of +the build system. This can normally be the result of running the +`config.guess' shell script, and it is reasonable to use +`--build=`config.guess`'. + + The `--host' option is used to specify the configuration name of the +host system. + + As we explained earlier, `config.guess' is used to set the default +value for the `--host' option (*note Using the Host Type::). We can +now see that since `config.guess' returns the type of system on which +it is run, it really identifies the build system. Since the host +system is normally the same as the build system (i.e., people do not +normally build using a cross compiler), it is reasonable to use the +result of `config.guess' as the default for the host system when the +`--host' option is not used. + + It might seem that if the `--host' option were used without the +`--build' option that the configure script could run `config.guess' to +determine the build system, and presume a Canadian Cross if the result +of `config.guess' differed from the `--host' option. However, for +historical reasons, some configure scripts are routinely run using an +explicit `--host' option, rather than using the default from +`config.guess'. As noted earlier, it is difficult or impossible to +reliably compare configuration names (*note Using the Target Type::). +Therefore, by convention, if the `--host' option is used, but the +`--build' option is not used, then the build system defaults to the +host system. + + +File: configure.info, Node: CCross not in Cygnus Tree, Next: CCross in Cygnus Tree, Prev: Build and Host Options, Up: Canadian Cross + +6.5 Canadian Cross not in Cygnus Tree. +====================================== + +If you are not using the Cygnus tree, you must explicitly specify the +cross tools which you want to use to build the program. This is done by +setting environment variables before running the `configure' script. + + You must normally set at least the environment variables `CC', `AR', +and `RANLIB' to the cross tools which you want to use to build. + + For some programs, you must set additional cross tools as well, such +as `AS', `LD', or `NM'. + + You would set these environment variables to the build cross tools +which you are going to use. + + For example, if you are building a Solaris program on a GNU/Linux +system, and your GNU/Linux cross Solaris compiler were named +`solaris-gcc', then you would set the environment variable `CC' to +`solaris-gcc'. + + +File: configure.info, Node: CCross in Cygnus Tree, Next: Supporting Canadian Cross, Prev: CCross not in Cygnus Tree, Up: Canadian Cross + +6.6 Canadian Cross in Cygnus Tree +================================= + +This section describes configuring and building a Canadian Cross when +using the Cygnus tree. + +* Menu: + +* Standard Cygnus CCross:: Building a Normal Program. +* Cross Cygnus CCross:: Building a Cross Program. + + +File: configure.info, Node: Standard Cygnus CCross, Next: Cross Cygnus CCross, Up: CCross in Cygnus Tree + +6.6.1 Building a Normal Program +------------------------------- + +When configuring a Canadian Cross in the Cygnus tree, all the +appropriate environment variables are automatically set to `HOST-TOOL', +where HOST is the value used for the `--host' option, and TOOL is the +name of the tool (e.g., `gcc', `as', etc.). These tools must be on +your `PATH'. + + Adding a prefix of HOST will give the usual name for the build cross +host tools. To see this, consider that when these cross tools were +built, they were configured to run on the build system and to produce +code for the host system. That is, they were configured with a +`--target' option that is the same as the system which we are now +calling the host. Recall that the default name for installed cross +tools uses the target system as a prefix (*note Using the Target +Type::). Since that is the system which we are now calling the host, +HOST is the right prefix to use. + + For example, if you configure with `--build=i386-linux-gnu' and +`--host=solaris', then the Cygnus tree will automatically default to +using the compiler `solaris-gcc'. You must have previously built and +installed this compiler, probably by doing a build with no `--host' +option and with a `--target' option of `solaris'. + + +File: configure.info, Node: Cross Cygnus CCross, Prev: Standard Cygnus CCross, Up: CCross in Cygnus Tree + +6.6.2 Building a Cross Program +------------------------------ + +There are additional considerations if you want to build a cross +compiler, rather than a native compiler, in the Cygnus tree using a +Canadian Cross. + + When you build a cross compiler using the Cygnus tree, then the +target libraries will normally be built with the newly built target +compiler (*note Host and Target Libraries::). However, this will not +work when building with a Canadian Cross. This is because the newly +built target compiler will be a program which runs on the host system, +and therefore will not be able to run on the build system. + + Therefore, when building a cross compiler with the Cygnus tree, you +must first install a set of build cross target tools. These tools will +be used when building the target libraries. + + Note that this is not a requirement of a Canadian Cross in general. +For example, it would be possible to build just the host cross target +tools on the build system, to copy the tools to the host system, and to +build the target libraries on the host system. The requirement for +build cross target tools is imposed by the Cygnus tree, which expects +to be able to build both host programs and target libraries in a single +`configure'/`make' step. Because it builds these in a single step, it +expects to be able to build the target libraries on the build system, +which means that it must use a build cross target toolchain. + + For example, suppose you want to build a Windows cross MIPS ELF +compiler on a GNU/Linux system. You must have previously installed +both a GNU/Linux cross Windows compiler and a GNU/Linux cross MIPS ELF +compiler. + + In order to build the Windows (configuration name `i386-cygwin32') +cross MIPS ELF (configure name `mips-elf') compiler, you might execute +the following commands (long command lines are broken across lines with +a trailing backslash as a continuation character). + + mkdir linux-x-cygwin32 + cd linux-x-cygwin32 + SRCDIR/configure --target i386-cygwin32 --prefix=INSTALLDIR \ + --exec-prefix=INSTALLDIR/H-i386-linux + make + make install + cd .. + mkdir linux-x-mips-elf + cd linux-x-mips-elf + SRCDIR/configure --target mips-elf --prefix=INSTALLDIR \ + --exec-prefix=INSTALLDIR/H-i386-linux + make + make install + cd .. + mkdir cygwin32-x-mips-elf + cd cygwin32-x-mips-elf + SRCDIR/configure --build=i386-linux-gnu --host=i386-cygwin32 \ + --target=mips-elf --prefix=WININSTALLDIR \ + --exec-prefix=WININSTALLDIR/H-i386-cygwin32 + make + make install + + You would then copy the contents of WININSTALLDIR over to the +Windows machine, and run the resulting programs. + + +File: configure.info, Node: Supporting Canadian Cross, Prev: CCross in Cygnus Tree, Up: Canadian Cross + +6.7 Supporting Canadian Cross +============================= + +If you want to make it possible to build a program you are developing +using a Canadian Cross, you must take some care when writing your +configure and make rules. Simple cases will normally work correctly. +However, it is not hard to write configure and make tests which will +fail in a Canadian Cross. + +* Menu: + +* CCross in Configure:: Supporting Canadian Cross in Configure Scripts. +* CCross in Make:: Supporting Canadian Cross in Makefiles. + + +File: configure.info, Node: CCross in Configure, Next: CCross in Make, Up: Supporting Canadian Cross + +6.7.1 Supporting Canadian Cross in Configure Scripts +---------------------------------------------------- + +In a `configure.in' file, after calling `AC_PROG_CC', you can find out +whether this is a Canadian Cross configure by examining the shell +variable `cross_compiling'. In a Canadian Cross, which means that the +compiler is a cross compiler, `cross_compiling' will be `yes'. In a +normal configuration, `cross_compiling' will be `no'. + + You ordinarily do not need to know the type of the build system in a +configure script. However, if you do need that information, you can get +it by using the macro `AC_CANONICAL_SYSTEM', the same macro that is +used to determine the target system. This macro will set the variables +`build', `build_alias', `build_cpu', `build_vendor', and `build_os', +which correspond to the similar `target' and `host' variables, except +that they describe the build system. + + When writing tests in `configure.in', you must remember that you +want to test the host environment, not the build environment. + + Macros like `AC_CHECK_FUNCS' which use the compiler will test the +host environment. That is because the tests will be done by running the +compiler, which is actually a build cross host compiler. If the +compiler can find the function, that means that the function is present +in the host environment. + + Tests like `test -f /dev/ptyp0', on the other hand, will test the +build environment. Remember that the configure script is running on the +build system, not the host system. If your configure scripts examines +files, those files will be on the build system. Whatever you determine +based on those files may or may not be the case on the host system. + + Most autoconf macros will work correctly for a Canadian Cross. The +main exception is `AC_TRY_RUN'. This macro tries to compile and run a +test program. This will fail in a Canadian Cross, because the program +will be compiled for the host system, which means that it will not run +on the build system. + + The `AC_TRY_RUN' macro provides an optional argument to tell the +configure script what to do in a Canadian Cross. If that argument is +not present, you will get a warning when you run `autoconf': + warning: AC_TRY_RUN called without default to allow cross compiling + This tells you that the resulting `configure' script will not work +with a Canadian Cross. + + In some cases while it may better to perform a test at configure +time, it is also possible to perform the test at run time. In such a +case you can use the cross compiling argument to `AC_TRY_RUN' to tell +your program that the test could not be performed at configure time. + + There are a few other autoconf macros which will not work correctly +with a Canadian Cross: a partial list is `AC_FUNC_GETPGRP', +`AC_FUNC_SETPGRP', `AC_FUNC_SETVBUF_REVERSED', and +`AC_SYS_RESTARTABLE_SYSCALLS'. The `AC_CHECK_SIZEOF' macro is +generally not very useful with a Canadian Cross; it permits an optional +argument indicating the default size, but there is no way to know what +the correct default should be. + + +File: configure.info, Node: CCross in Make, Prev: CCross in Configure, Up: Supporting Canadian Cross + +6.7.2 Supporting Canadian Cross in Makefiles. +--------------------------------------------- + +The main Canadian Cross issue in a `Makefile' arises when you want to +use a subsidiary program to generate code or data which you will then +include in your real program. + + If you compile this subsidiary program using `$(CC)' in the usual +way, you will not be able to run it. This is because `$(CC)' will +build a program for the host system, but the program is being built on +the build system. + + You must instead use a compiler for the build system, rather than the +host system. In the Cygnus tree, this make variable `$(CC_FOR_BUILD)' +will hold a compiler for the build system. + + Note that you should not include `config.h' in a file you are +compiling with `$(CC_FOR_BUILD)'. The `configure' script will build +`config.h' with information for the host system. However, you are +compiling the file using a compiler for the build system (a native +compiler). Subsidiary programs are normally simple filters which do no +user interaction, and it is normally possible to write them in a highly +portable fashion so that the absence of `config.h' is not crucial. + + The gcc `Makefile.in' shows a complex situation in which certain +files, such as `rtl.c', must be compiled into both subsidiary programs +run on the build system and into the final program. This approach may +be of interest for advanced build system hackers. Note that the build +system compiler is rather confusingly called `HOST_CC'. + + +File: configure.info, Node: Cygnus Configure, Next: Multilibs, Prev: Canadian Cross, Up: Top + +7 Cygnus Configure +****************** + +The Cygnus configure script predates autoconf. All of its interesting +features have been incorporated into autoconf. No new programs should +be written to use the Cygnus configure script. + + However, the Cygnus configure script is still used in a few places: +at the top of the Cygnus tree and in a few target libraries in the +Cygnus tree. Until those uses have been replaced with autoconf, some +brief notes are appropriate here. This is not complete documentation, +but it should be possible to use this as a guide while examining the +scripts themselves. + +* Menu: + +* Cygnus Configure Basics:: Cygnus Configure Basics. +* Cygnus Configure in C++ Libraries:: Cygnus Configure in C++ Libraries. + + +File: configure.info, Node: Cygnus Configure Basics, Next: Cygnus Configure in C++ Libraries, Up: Cygnus Configure + +7.1 Cygnus Configure Basics +=========================== + +Cygnus configure does not use any generated files; there is no program +corresponding to `autoconf'. Instead, there is a single shell script +named `configure' which may be found at the top of the Cygnus tree. +This shell script was written by hand; it was not generated by +autoconf, and it is incorrect, and indeed harmful, to run `autoconf' in +the top level of a Cygnus tree. + + Cygnus configure works in a particular directory by examining the +file `configure.in' in that directory. That file is broken into four +separate shell scripts. + + The first is the contents of `configure.in' up to a line that starts +with `# per-host:'. This is the common part. + + The second is the rest of `configure.in' up to a line that starts +with `# per-target:'. This is the per host part. + + The third is the rest of `configure.in' up to a line that starts +with `# post-target:'. This is the per target part. + + The fourth is the remainder of `configure.in'. This is the post +target part. + + If any of these comment lines are missing, the corresponding shell +script is empty. + + Cygnus configure will first execute the common part. This must set +the shell variable `srctrigger' to the name of a source file, to +confirm that Cygnus configure is looking at the right directory. This +may set the shell variables `package_makefile_frag' and +`package_makefile_rules_frag'. + + Cygnus configure will next set the `build' and `host' shell +variables, and execute the per host part. This may set the shell +variable `host_makefile_frag'. + + Cygnus configure will next set the `target' variable, and execute +the per target part. This may set the shell variable +`target_makefile_frag'. + + Any of these scripts may set the `subdirs' shell variable. This +variable is a list of subdirectories where a `Makefile.in' file may be +found. Cygnus configure will automatically look for a `Makefile.in' +file in the current directory. The `subdirs' shell variable is not +normally used, and I believe that the only directory which uses it at +present is `newlib'. + + For each `Makefile.in', Cygnus configure will automatically create a +`Makefile' by adding definitions for `make' variables such as `host' +and `target', and automatically editing the values of `make' variables +such as `prefix' if they are present. + + Also, if any of the `makefile_frag' shell variables are set, Cygnus +configure will interpret them as file names relative to either the +working directory or the source directory, and will read the contents of +the file into the generated `Makefile'. The file contents will be read +in after the first line in `Makefile.in' which starts with `####'. + + These `Makefile' fragments are used to customize behaviour for a +particular host or target. They serve to select particular files to +compile, and to define particular preprocessor macros by providing +values for `make' variables which are then used during compilation. +Cygnus configure, unlike autoconf, normally does not do feature tests, +and normally requires support to be added manually for each new host. + + The `Makefile' fragment support is similar to the autoconf +`AC_SUBST_FILE' macro. + + After creating each `Makefile', the post target script will be run +(i.e., it may be run several times). This script may further customize +the `Makefile'. When it is run, the shell variable `Makefile' will +hold the name of the `Makefile', including the appropriate directory +component. + + Like an autoconf generated `configure' script, Cygnus configure will +create a file named `config.status' which, when run, will automatically +recreate the configuration. The `config.status' file will simply +execute the Cygnus configure script again with the appropriate +arguments. + + Any of the parts of `configure.in' may set the shell variables +`files' and `links'. Cygnus configure will set up symlinks from the +names in `links' to the files named in `files'. This is similar to the +autoconf `AC_LINK_FILES' macro. + + Finally, any of the parts of `configure.in' may set the shell +variable `configdirs' to a set of subdirectories. If it is set, Cygnus +configure will recursively run the configure process in each +subdirectory. If the subdirectory uses Cygnus configure, it will +contain a `configure.in' file but no `configure' file, in which case +Cygnus configure will invoke itself recursively. If the subdirectory +has a `configure' file, Cygnus configure assumes that it is an autoconf +generated `configure' script, and simply invokes it directly. + + +File: configure.info, Node: Cygnus Configure in C++ Libraries, Prev: Cygnus Configure Basics, Up: Cygnus Configure + +7.2 Cygnus Configure in C++ Libraries +===================================== + +The C++ library configure system, written by Per Bothner, deserves +special mention. It uses Cygnus configure, but it does feature testing +like that done by autoconf generated `configure' scripts. This +approach is used in the libraries `libio', `libstdc++', and `libg++'. + + Most of the `Makefile' information is written out by the shell +script `libio/config.shared'. Each `configure.in' file sets certain +shell variables, and then invokes `config.shared' to create two package +`Makefile' fragments. These fragments are then incorporated into the +resulting `Makefile' by the Cygnus configure script. + + The file `_G_config.h' is created in the `libio' object directory by +running the shell script `libio/gen-params'. This shell script uses +feature tests to define macros and typedefs in `_G_config.h'. + + +File: configure.info, Node: Multilibs, Next: FAQ, Prev: Cygnus Configure, Up: Top + +8 Multilibs +*********** + +For some targets gcc may have different processor requirements depending +upon command line options. An obvious example is the `-msoft-float' +option supported on several processors. This option means that the +floating point registers are not available, which means that floating +point operations must be done by calling an emulation subroutine rather +than by using machine instructions. + + For such options, gcc is often configured to compile target libraries +twice: once with `-msoft-float' and once without. When gcc compiles +target libraries more than once, the resulting libraries are called +"multilibs". + + Multilibs are not really part of the GNU configure and build system, +but we discuss them here since they require support in the `configure' +scripts and `Makefile's used for target libraries. + +* Menu: + +* Multilibs in gcc:: Multilibs in gcc. +* Multilibs in Target Libraries:: Multilibs in Target Libraries. + + +File: configure.info, Node: Multilibs in gcc, Next: Multilibs in Target Libraries, Up: Multilibs + +8.1 Multilibs in gcc +==================== + +In gcc, multilibs are defined by setting the variable +`MULTILIB_OPTIONS' in the target `Makefile' fragment. Several other +`MULTILIB' variables may also be defined there. *Note The Target +Makefile Fragment: (gcc)Target Fragment. + + If you have built gcc, you can see what multilibs it uses by running +it with the `-print-multi-lib' option. The output `.;' means that no +multilibs are used. In general, the output is a sequence of lines, one +per multilib. The first part of each line, up to the `;', is the name +of the multilib directory. The second part is a list of compiler +options separated by `@' characters. + + Multilibs are built in a tree of directories. The top of the tree, +represented by `.' in the list of multilib directories, is the default +library to use when no special compiler options are used. The +subdirectories of the tree hold versions of the library to use when +particular compiler options are used. + + +File: configure.info, Node: Multilibs in Target Libraries, Prev: Multilibs in gcc, Up: Multilibs + +8.2 Multilibs in Target Libraries +================================= + +The target libraries in the Cygnus tree are automatically built with +multilibs. That means that each library is built multiple times. + + This default is set in the top level `configure.in' file, by adding +`--enable-multilib' to the list of arguments passed to configure when +it is run for the target libraries (*note Host and Target Libraries::). + + Each target library uses the shell script `config-ml.in', written by +Doug Evans, to prepare to build target libraries. This shell script is +invoked after the `Makefile' has been created by the `configure' +script. If multilibs are not enabled, it does nothing, otherwise it +modifies the `Makefile' to support multilibs. + + The `config-ml.in' script makes one copy of the `Makefile' for each +multilib in the appropriate subdirectory. When configuring in the +source directory (which is not recommended), it will build a symlink +tree of the sources in each subdirectory. + + The `config-ml.in' script sets several variables in the various +`Makefile's. The `Makefile.in' must have definitions for these +variables already; `config-ml.in' simply changes the existing values. +The `Makefile' should use default values for these variables which will +do the right thing in the subdirectories. + +`MULTISRCTOP' + `config-ml.in' will set this to a sequence of `../' strings, where + the number of strings is the number of multilib levels in the + source tree. The default value should be the empty string. + +`MULTIBUILDTOP' + `config-ml.in' will set this to a sequence of `../' strings, where + the number of strings is number of multilib levels in the object + directory. The default value should be the empty string. This + will differ from `MULTISRCTOP' when configuring in the source tree + (which is not recommended). + +`MULTIDIRS' + In the top level `Makefile' only, `config-ml.in' will set this to + the list of multilib subdirectories. The default value should be + the empty string. + +`MULTISUBDIR' + `config-ml.in' will set this to the installed subdirectory name to + use for this subdirectory, with a leading `/'. The default value + shold be the empty string. + +`MULTIDO' +`MULTICLEAN' + In the top level `Makefile' only, `config-ml.in' will set these + variables to commands to use when doing a recursive make. These + variables should both default to the string `true', so that by + default nothing happens. + + All references to the parent of the source directory should use the +variable `MULTISRCTOP'. Instead of writing `$(srcdir)/..', you must +write `$(srcdir)/$(MULTISRCTOP)..'. + + Similarly, references to the parent of the object directory should +use the variable `MULTIBUILDTOP'. + + In the installation target, the libraries should be installed in the +subdirectory `MULTISUBDIR'. Instead of installing +`$(libdir)/libfoo.a', install `$(libdir)$(MULTISUBDIR)/libfoo.a'. + + The `config-ml.in' script also modifies the top level `Makefile' to +add `multi-do' and `multi-clean' targets which are used when building +multilibs. + + The default target of the `Makefile' should include the following +command: + @$(MULTIDO) $(FLAGS_TO_PASS) DO=all multi-do + This assumes that `$(FLAGS_TO_PASS)' is defined as a set of +variables to pass to a recursive invocation of `make'. This will build +all the multilibs. Note that the default value of `MULTIDO' is `true', +so by default this command will do nothing. It will only do something +in the top level `Makefile' if multilibs were enabled. + + The `install' target of the `Makefile' should include the following +command: + @$(MULTIDO) $(FLAGS_TO_PASS) DO=install multi-do + + In general, any operation, other than clean, which should be +performed on all the multilibs should use a `$(MULTIDO)' line, setting +the variable `DO' to the target of each recursive call to `make'. + + The `clean' targets (`clean', `mostlyclean', etc.) should use +`$(MULTICLEAN)'. For example, the `clean' target should do this: + @$(MULTICLEAN) DO=clean multi-clean + + +File: configure.info, Node: FAQ, Next: Index, Prev: Multilibs, Up: Top + +9 Frequently Asked Questions +**************************** + +Which do I run first, `autoconf' or `automake'? + Except when you first add autoconf or automake support to a + package, you shouldn't run either by hand. Instead, configure + with the `--enable-maintainer-mode' option, and let `make' take + care of it. + +`autoconf' says something about undefined macros. + This means that you have macros in your `configure.in' which are + not defined by `autoconf'. You may be using an old version of + `autoconf'; try building and installing a newer one. Make sure the + newly installled `autoconf' is first on your `PATH'. Also, see + the next question. + +My `configure' script has stuff like `CY_GNU_GETTEXT' in it. + This means that you have macros in your `configure.in' which should + be defined in your `aclocal.m4' file, but aren't. This usually + means that `aclocal' was not able to appropriate definitions of the + macros. Make sure that you have installed all the packages you + need. In particular, make sure that you have installed libtool + (this is where `AM_PROG_LIBTOOL' is defined) and gettext (this is + where `CY_GNU_GETTEXT' is defined, at least in the Cygnus version + of gettext). + +My `Makefile' has `@' characters in it. + This may mean that you tried to use an autoconf substitution in + your `Makefile.in' without adding the appropriate `AC_SUBST' call + to your `configure' script. Or it may just mean that you need to + rebuild `Makefile' in your build directory. To rebuild `Makefile' + from `Makefile.in', run the shell script `config.status' with no + arguments. If you need to force `configure' to run again, first + run `config.status --recheck'. These runs are normally done + automatically by `Makefile' targets, but if your `Makefile' has + gotten messed up you'll need to help them along. + +Why do I have to run both `config.status --recheck' and `config.status'? + Normally, you don't; they will be run automatically by `Makefile' + targets. If you do need to run them, use `config.status --recheck' + to run the `configure' script again with the same arguments as the + first time you ran it. Use `config.status' (with no arguments) to + regenerate all files (`Makefile', `config.h', etc.) based on the + results of the configure script. The two cases are separate + because it isn't always necessary to regenerate all the files + after running `config.status --recheck'. The `Makefile' targets + generated by automake will use the environment variables + `CONFIG_FILES' and `CONFIG_HEADERS' to only regenerate files as + they are needed. + +What is the Cygnus tree? + The Cygnus tree is used for various packages including gdb, the GNU + binutils, and egcs. It is also, of course, used for Cygnus + releases. It is the build system which was developed at Cygnus, + using the Cygnus configure script. It permits building many + different packages with a single configure and make. The + configure scripts in the tree are being converted to autoconf, but + the general build structure remains intact. + +Why do I have to keep rebuilding and reinstalling the tools? + I know, it's a pain. Unfortunately, there are bugs in the tools + themselves which need to be fixed, and each time that happens + everybody who uses the tools need to reinstall new versions of + them. I don't know if there is going to be a clever fix until the + tools stabilize. + +Why not just have a Cygnus tree `make' target to update the tools? + The tools unfortunately need to be installed before they can be + used. That means that they must be built using an appropriate + prefix, and it seems unwise to assume that every configuration + uses an appropriate prefix. It might be possible to make them + work in place, or it might be possible to install them in some + subdirectory; so far these approaches have not been implemented. + + +File: configure.info, Node: Index, Prev: FAQ, Up: Top + +Index +***** + + +* Menu: + +* --build option: Build and Host Options. + (line 9) +* --host option: Build and Host Options. + (line 14) +* --target option: Specifying the Target. + (line 10) +* _GNU_SOURCE: Write configure.in. (line 134) +* AC_CANONICAL_HOST: Using the Host Type. (line 10) +* AC_CANONICAL_SYSTEM: Using the Target Type. + (line 6) +* AC_CONFIG_HEADER: Write configure.in. (line 66) +* AC_EXEEXT: Write configure.in. (line 86) +* AC_INIT: Write configure.in. (line 38) +* AC_OUTPUT: Write configure.in. (line 142) +* AC_PREREQ: Write configure.in. (line 42) +* AC_PROG_CC: Write configure.in. (line 103) +* AC_PROG_CXX: Write configure.in. (line 117) +* acconfig.h: Written Developer Files. + (line 27) +* acconfig.h, writing: Write acconfig.h. (line 6) +* acinclude.m4: Written Developer Files. + (line 37) +* aclocal.m4: Generated Developer Files. + (line 33) +* AM_CONFIG_HEADER: Write configure.in. (line 53) +* AM_DISABLE_SHARED: Write configure.in. (line 127) +* AM_EXEEXT: Write configure.in. (line 86) +* AM_INIT_AUTOMAKE: Write configure.in. (line 48) +* AM_MAINTAINER_MODE: Write configure.in. (line 70) +* AM_PROG_LIBTOOL: Write configure.in. (line 122) +* AM_PROG_LIBTOOL in configure: FAQ. (line 19) +* build option: Build and Host Options. + (line 9) +* building with a cross compiler: Canadian Cross. (line 6) +* canadian cross: Canadian Cross. (line 6) +* canadian cross in configure: CCross in Configure. (line 6) +* canadian cross in cygnus tree: CCross in Cygnus Tree. + (line 6) +* canadian cross in makefile: CCross in Make. (line 6) +* canadian cross, configuring: Build and Host Options. + (line 6) +* canonical system names: Configuration Names. (line 6) +* config.cache: Build Files Description. + (line 28) +* config.h: Build Files Description. + (line 23) +* config.h.in: Generated Developer Files. + (line 45) +* config.in: Generated Developer Files. + (line 45) +* config.status: Build Files Description. + (line 9) +* config.status --recheck: FAQ. (line 40) +* configuration names: Configuration Names. (line 6) +* configuration triplets: Configuration Names. (line 6) +* configure: Generated Developer Files. + (line 21) +* configure build system: Build and Host Options. + (line 9) +* configure host: Build and Host Options. + (line 14) +* configure target: Specifying the Target. + (line 10) +* configure.in: Written Developer Files. + (line 9) +* configure.in, writing: Write configure.in. (line 6) +* configuring a canadian cross: Build and Host Options. + (line 6) +* cross compiler: Cross Compilation Concepts. + (line 6) +* cross compiler, building with: Canadian Cross. (line 6) +* cross tools: Cross Compilation Tools. + (line 6) +* CY_GNU_GETTEXT in configure: FAQ. (line 19) +* cygnus configure: Cygnus Configure. (line 6) +* goals: Goals. (line 6) +* history: History. (line 6) +* host names: Configuration Names. (line 6) +* host option: Build and Host Options. + (line 14) +* host system: Host and Target. (line 6) +* host triplets: Configuration Names. (line 6) +* HOST_CC: CCross in Make. (line 27) +* libg++ configure: Cygnus Configure in C++ Libraries. + (line 6) +* libio configure: Cygnus Configure in C++ Libraries. + (line 6) +* libstdc++ configure: Cygnus Configure in C++ Libraries. + (line 6) +* Makefile: Build Files Description. + (line 18) +* Makefile, garbage characters: FAQ. (line 29) +* Makefile.am: Written Developer Files. + (line 18) +* Makefile.am, writing: Write Makefile.am. (line 6) +* Makefile.in: Generated Developer Files. + (line 26) +* multilibs: Multilibs. (line 6) +* stamp-h: Build Files Description. + (line 41) +* stamp-h.in: Generated Developer Files. + (line 54) +* system names: Configuration Names. (line 6) +* system types: Configuration Names. (line 6) +* target option: Specifying the Target. + (line 10) +* target system: Host and Target. (line 6) +* triplets: Configuration Names. (line 6) +* undefined macros: FAQ. (line 12) + + + +Tag Table: +Node: Top971 +Node: Introduction1499 +Node: Goals2581 +Node: Tools3305 +Node: History4299 +Node: Building7297 +Node: Getting Started10560 +Node: Write configure.in11073 +Node: Write Makefile.am18324 +Node: Write acconfig.h21501 +Node: Generate files23038 +Node: Getting Started Example25004 +Node: Getting Started Example 125759 +Node: Getting Started Example 227680 +Node: Getting Started Example 330675 +Node: Generate Files in Example33039 +Node: Files34129 +Node: Developer Files34740 +Node: Developer Files Picture35120 +Node: Written Developer Files36408 +Node: Generated Developer Files38960 +Node: Build Files42104 +Node: Build Files Picture42765 +Node: Build Files Description43529 +Node: Support Files45535 +Node: Configuration Names48417 +Node: Configuration Name Definition48917 +Node: Using Configuration Names51240 +Node: Cross Compilation Tools53210 +Node: Cross Compilation Concepts53901 +Node: Host and Target54869 +Node: Using the Host Type56370 +Node: Specifying the Target57719 +Node: Using the Target Type58508 +Node: Cross Tools in the Cygnus Tree61939 +Node: Host and Target Libraries62996 +Node: Target Library Configure Scripts66745 +Node: Make Targets in Cygnus Tree69837 +Node: Target libiberty71185 +Node: Canadian Cross72572 +Node: Canadian Cross Example73413 +Node: Canadian Cross Concepts74532 +Node: Build Cross Host Tools76044 +Node: Build and Host Options76996 +Node: CCross not in Cygnus Tree78782 +Node: CCross in Cygnus Tree79760 +Node: Standard Cygnus CCross80181 +Node: Cross Cygnus CCross81545 +Node: Supporting Canadian Cross84345 +Node: CCross in Configure84960 +Node: CCross in Make88128 +Node: Cygnus Configure89731 +Node: Cygnus Configure Basics90566 +Node: Cygnus Configure in C++ Libraries95244 +Node: Multilibs96251 +Node: Multilibs in gcc97296 +Node: Multilibs in Target Libraries98374 +Node: FAQ102565 +Node: Index106665 + +End Tag Table diff --git a/uclibc-crosstools-gcc-4.4.2-1/usr/share/info/dir b/uclibc-crosstools-gcc-4.4.2-1/usr/share/info/dir new file mode 100644 index 0000000..13c3722 --- /dev/null +++ b/uclibc-crosstools-gcc-4.4.2-1/usr/share/info/dir @@ -0,0 +1,43 @@ +This is the file .../info/dir, which contains the +topmost node of the Info hierarchy, called (dir)Top. +The first time you invoke Info you start off looking at this node. + +File: dir, Node: Top This is the top of the INFO tree + + This (the Directory node) gives a menu of major topics. + Typing "q" exits, "?" lists all Info commands, "d" returns here, + "h" gives a primer for first-timers, + "mEmacs<Return>" visits the Emacs manual, etc. + + In Emacs, you can click mouse button 2 on a menu item or cross reference + to select it. + +* Menu: + +Miscellaneous +* As: (as). The GNU assembler. +* Bfd: (bfd). The Binary File Descriptor library. +* Gas: (as). The GNU assembler. +* Ld: (ld). The GNU linker. +* gprof: (gprof). Profiling your program's execution + +Individual utilities +* addr2line: (binutils)addr2line. Convert addresses to file and line. +* ar: (binutils)ar. Create, modify, and extract from archives. +* c++filt: (binutils)c++filt. Filter to demangle encoded C++ symbols. +* cxxfilt: (binutils)c++filt. MS-DOS name for c++filt. +* dlltool: (binutils)dlltool. Create files needed to build and use DLLs. +* nlmconv: (binutils)nlmconv. Converts object code into an NLM. +* nm: (binutils)nm. List symbols from object files. +* objcopy: (binutils)objcopy. Copy and translate object files. +* objdump: (binutils)objdump. Display information from object files. +* ranlib: (binutils)ranlib. Generate index to archive contents. +* readelf: (binutils)readelf. Display the contents of ELF format files. +* size: (binutils)size. List section sizes and total size. +* strings: (binutils)strings. List printable strings from files. +* strip: (binutils)strip. Discard symbols. +* windmc: (binutils)windmc. Generator for Windows message resources. +* windres: (binutils)windres. Manipulate Windows resources. + +Software development +* Binutils: (binutils). The GNU binary utilities. diff --git a/uclibc-crosstools-gcc-4.4.2-1/usr/share/info/gprof.info b/uclibc-crosstools-gcc-4.4.2-1/usr/share/info/gprof.info new file mode 100644 index 0000000..eb9943a --- /dev/null +++ b/uclibc-crosstools-gcc-4.4.2-1/usr/share/info/gprof.info @@ -0,0 +1,2469 @@ +This is gprof.info, produced by makeinfo version 4.8 from gprof.texi. + +START-INFO-DIR-ENTRY +* gprof: (gprof). Profiling your program's execution +END-INFO-DIR-ENTRY + + This file documents the gprof profiler of the GNU system. + + Copyright (C) 1988, 92, 97, 98, 99, 2000, 2001, 2003, 2007, 2008, +2009 Free Software Foundation, Inc. + + Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation; with no +Invariant Sections, with no Front-Cover Texts, and with no Back-Cover +Texts. A copy of the license is included in the section entitled "GNU +Free Documentation License". + + +File: gprof.info, Node: Top, Next: Introduction, Up: (dir) + +Profiling a Program: Where Does It Spend Its Time? +************************************************** + +This manual describes the GNU profiler, `gprof', and how you can use it +to determine which parts of a program are taking most of the execution +time. We assume that you know how to write, compile, and execute +programs. GNU `gprof' was written by Jay Fenlason. + + This manual is for `gprof' (GNU Binutils) version 2.20. + + This document is distributed under the terms of the GNU Free +Documentation License version 1.3. A copy of the license is included +in the section entitled "GNU Free Documentation License". + +* Menu: + +* Introduction:: What profiling means, and why it is useful. + +* Compiling:: How to compile your program for profiling. +* Executing:: Executing your program to generate profile data +* Invoking:: How to run `gprof', and its options + +* Output:: Interpreting `gprof''s output + +* Inaccuracy:: Potential problems you should be aware of +* How do I?:: Answers to common questions +* Incompatibilities:: (between GNU `gprof' and Unix `gprof'.) +* Details:: Details of how profiling is done +* GNU Free Documentation License:: GNU Free Documentation License + + +File: gprof.info, Node: Introduction, Next: Compiling, Prev: Top, Up: Top + +1 Introduction to Profiling +*************************** + +Profiling allows you to learn where your program spent its time and +which functions called which other functions while it was executing. +This information can show you which pieces of your program are slower +than you expected, and might be candidates for rewriting to make your +program execute faster. It can also tell you which functions are being +called more or less often than you expected. This may help you spot +bugs that had otherwise been unnoticed. + + Since the profiler uses information collected during the actual +execution of your program, it can be used on programs that are too +large or too complex to analyze by reading the source. However, how +your program is run will affect the information that shows up in the +profile data. If you don't use some feature of your program while it +is being profiled, no profile information will be generated for that +feature. + + Profiling has several steps: + + * You must compile and link your program with profiling enabled. + *Note Compiling a Program for Profiling: Compiling. + + * You must execute your program to generate a profile data file. + *Note Executing the Program: Executing. + + * You must run `gprof' to analyze the profile data. *Note `gprof' + Command Summary: Invoking. + + The next three chapters explain these steps in greater detail. + + Several forms of output are available from the analysis. + + The "flat profile" shows how much time your program spent in each +function, and how many times that function was called. If you simply +want to know which functions burn most of the cycles, it is stated +concisely here. *Note The Flat Profile: Flat Profile. + + The "call graph" shows, for each function, which functions called +it, which other functions it called, and how many times. There is also +an estimate of how much time was spent in the subroutines of each +function. This can suggest places where you might try to eliminate +function calls that use a lot of time. *Note The Call Graph: Call +Graph. + + The "annotated source" listing is a copy of the program's source +code, labeled with the number of times each line of the program was +executed. *Note The Annotated Source Listing: Annotated Source. + + To better understand how profiling works, you may wish to read a +description of its implementation. *Note Implementation of Profiling: +Implementation. + + +File: gprof.info, Node: Compiling, Next: Executing, Prev: Introduction, Up: Top + +2 Compiling a Program for Profiling +*********************************** + +The first step in generating profile information for your program is to +compile and link it with profiling enabled. + + To compile a source file for profiling, specify the `-pg' option when +you run the compiler. (This is in addition to the options you normally +use.) + + To link the program for profiling, if you use a compiler such as `cc' +to do the linking, simply specify `-pg' in addition to your usual +options. The same option, `-pg', alters either compilation or linking +to do what is necessary for profiling. Here are examples: + + cc -g -c myprog.c utils.c -pg + cc -o myprog myprog.o utils.o -pg + + The `-pg' option also works with a command that both compiles and +links: + + cc -o myprog myprog.c utils.c -g -pg + + Note: The `-pg' option must be part of your compilation options as +well as your link options. If it is not then no call-graph data will +be gathered and when you run `gprof' you will get an error message like +this: + + gprof: gmon.out file is missing call-graph data + + If you add the `-Q' switch to suppress the printing of the call +graph data you will still be able to see the time samples: + + Flat profile: + + Each sample counts as 0.01 seconds. + % cumulative self self total + time seconds seconds calls Ts/call Ts/call name + 44.12 0.07 0.07 zazLoop + 35.29 0.14 0.06 main + 20.59 0.17 0.04 bazMillion + + If you run the linker `ld' directly instead of through a compiler +such as `cc', you may have to specify a profiling startup file +`gcrt0.o' as the first input file instead of the usual startup file +`crt0.o'. In addition, you would probably want to specify the +profiling C library, `libc_p.a', by writing `-lc_p' instead of the +usual `-lc'. This is not absolutely necessary, but doing this gives +you number-of-calls information for standard library functions such as +`read' and `open'. For example: + + ld -o myprog /lib/gcrt0.o myprog.o utils.o -lc_p + + If you are running the program on a system which supports shared +libraries you may run into problems with the profiling support code in +a shared library being called before that library has been fully +initialised. This is usually detected by the program encountering a +segmentation fault as soon as it is run. The solution is to link +against a static version of the library containing the profiling +support code, which for `gcc' users can be done via the `-static' or +`-static-libgcc' command line option. For example: + + gcc -g -pg -static-libgcc myprog.c utils.c -o myprog + + If you compile only some of the modules of the program with `-pg', +you can still profile the program, but you won't get complete +information about the modules that were compiled without `-pg'. The +only information you get for the functions in those modules is the +total time spent in them; there is no record of how many times they +were called, or from where. This will not affect the flat profile +(except that the `calls' field for the functions will be blank), but +will greatly reduce the usefulness of the call graph. + + If you wish to perform line-by-line profiling you should use the +`gcov' tool instead of `gprof'. See that tool's manual or info pages +for more details of how to do this. + + Note, older versions of `gcc' produce line-by-line profiling +information that works with `gprof' rather than `gcov' so there is +still support for displaying this kind of information in `gprof'. *Note +Line-by-line Profiling: Line-by-line. + + It also worth noting that `gcc' implements a +`-finstrument-functions' command line option which will insert calls to +special user supplied instrumentation routines at the entry and exit of +every function in their program. This can be used to implement an +alternative profiling scheme. + + +File: gprof.info, Node: Executing, Next: Invoking, Prev: Compiling, Up: Top + +3 Executing the Program +*********************** + +Once the program is compiled for profiling, you must run it in order to +generate the information that `gprof' needs. Simply run the program as +usual, using the normal arguments, file names, etc. The program should +run normally, producing the same output as usual. It will, however, run +somewhat slower than normal because of the time spent collecting and +writing the profile data. + + The way you run the program--the arguments and input that you give +it--may have a dramatic effect on what the profile information shows. +The profile data will describe the parts of the program that were +activated for the particular input you use. For example, if the first +command you give to your program is to quit, the profile data will show +the time used in initialization and in cleanup, but not much else. + + Your program will write the profile data into a file called +`gmon.out' just before exiting. If there is already a file called +`gmon.out', its contents are overwritten. There is currently no way to +tell the program to write the profile data under a different name, but +you can rename the file afterwards if you are concerned that it may be +overwritten. + + In order to write the `gmon.out' file properly, your program must +exit normally: by returning from `main' or by calling `exit'. Calling +the low-level function `_exit' does not write the profile data, and +neither does abnormal termination due to an unhandled signal. + + The `gmon.out' file is written in the program's _current working +directory_ at the time it exits. This means that if your program calls +`chdir', the `gmon.out' file will be left in the last directory your +program `chdir''d to. If you don't have permission to write in this +directory, the file is not written, and you will get an error message. + + Older versions of the GNU profiling library may also write a file +called `bb.out'. This file, if present, contains an human-readable +listing of the basic-block execution counts. Unfortunately, the +appearance of a human-readable `bb.out' means the basic-block counts +didn't get written into `gmon.out'. The Perl script `bbconv.pl', +included with the `gprof' source distribution, will convert a `bb.out' +file into a format readable by `gprof'. Invoke it like this: + + bbconv.pl < bb.out > BH-DATA + + This translates the information in `bb.out' into a form that `gprof' +can understand. But you still need to tell `gprof' about the existence +of this translated information. To do that, include BB-DATA on the +`gprof' command line, _along with `gmon.out'_, like this: + + gprof OPTIONS EXECUTABLE-FILE gmon.out BB-DATA [YET-MORE-PROFILE-DATA-FILES...] [> OUTFILE] + + +File: gprof.info, Node: Invoking, Next: Output, Prev: Executing, Up: Top + +4 `gprof' Command Summary +************************* + +After you have a profile data file `gmon.out', you can run `gprof' to +interpret the information in it. The `gprof' program prints a flat +profile and a call graph on standard output. Typically you would +redirect the output of `gprof' into a file with `>'. + + You run `gprof' like this: + + gprof OPTIONS [EXECUTABLE-FILE [PROFILE-DATA-FILES...]] [> OUTFILE] + +Here square-brackets indicate optional arguments. + + If you omit the executable file name, the file `a.out' is used. If +you give no profile data file name, the file `gmon.out' is used. If +any file is not in the proper format, or if the profile data file does +not appear to belong to the executable file, an error message is +printed. + + You can give more than one profile data file by entering all their +names after the executable file name; then the statistics in all the +data files are summed together. + + The order of these options does not matter. + +* Menu: + +* Output Options:: Controlling `gprof''s output style +* Analysis Options:: Controlling how `gprof' analyzes its data +* Miscellaneous Options:: +* Deprecated Options:: Options you no longer need to use, but which + have been retained for compatibility +* Symspecs:: Specifying functions to include or exclude + + +File: gprof.info, Node: Output Options, Next: Analysis Options, Up: Invoking + +4.1 Output Options +================== + +These options specify which of several output formats `gprof' should +produce. + + Many of these options take an optional "symspec" to specify +functions to be included or excluded. These options can be specified +multiple times, with different symspecs, to include or exclude sets of +symbols. *Note Symspecs: Symspecs. + + Specifying any of these options overrides the default (`-p -q'), +which prints a flat profile and call graph analysis for all functions. + +`-A[SYMSPEC]' +`--annotated-source[=SYMSPEC]' + The `-A' option causes `gprof' to print annotated source code. If + SYMSPEC is specified, print output only for matching symbols. + *Note The Annotated Source Listing: Annotated Source. + +`-b' +`--brief' + If the `-b' option is given, `gprof' doesn't print the verbose + blurbs that try to explain the meaning of all of the fields in the + tables. This is useful if you intend to print out the output, or + are tired of seeing the blurbs. + +`-C[SYMSPEC]' +`--exec-counts[=SYMSPEC]' + The `-C' option causes `gprof' to print a tally of functions and + the number of times each was called. If SYMSPEC is specified, + print tally only for matching symbols. + + If the profile data file contains basic-block count records, + specifying the `-l' option, along with `-C', will cause basic-block + execution counts to be tallied and displayed. + +`-i' +`--file-info' + The `-i' option causes `gprof' to display summary information + about the profile data file(s) and then exit. The number of + histogram, call graph, and basic-block count records is displayed. + +`-I DIRS' +`--directory-path=DIRS' + The `-I' option specifies a list of search directories in which to + find source files. Environment variable GPROF_PATH can also be + used to convey this information. Used mostly for annotated source + output. + +`-J[SYMSPEC]' +`--no-annotated-source[=SYMSPEC]' + The `-J' option causes `gprof' not to print annotated source code. + If SYMSPEC is specified, `gprof' prints annotated source, but + excludes matching symbols. + +`-L' +`--print-path' + Normally, source filenames are printed with the path component + suppressed. The `-L' option causes `gprof' to print the full + pathname of source filenames, which is determined from symbolic + debugging information in the image file and is relative to the + directory in which the compiler was invoked. + +`-p[SYMSPEC]' +`--flat-profile[=SYMSPEC]' + The `-p' option causes `gprof' to print a flat profile. If + SYMSPEC is specified, print flat profile only for matching symbols. + *Note The Flat Profile: Flat Profile. + +`-P[SYMSPEC]' +`--no-flat-profile[=SYMSPEC]' + The `-P' option causes `gprof' to suppress printing a flat profile. + If SYMSPEC is specified, `gprof' prints a flat profile, but + excludes matching symbols. + +`-q[SYMSPEC]' +`--graph[=SYMSPEC]' + The `-q' option causes `gprof' to print the call graph analysis. + If SYMSPEC is specified, print call graph only for matching symbols + and their children. *Note The Call Graph: Call Graph. + +`-Q[SYMSPEC]' +`--no-graph[=SYMSPEC]' + The `-Q' option causes `gprof' to suppress printing the call graph. + If SYMSPEC is specified, `gprof' prints a call graph, but excludes + matching symbols. + +`-t' +`--table-length=NUM' + The `-t' option causes the NUM most active source lines in each + source file to be listed when source annotation is enabled. The + default is 10. + +`-y' +`--separate-files' + This option affects annotated source output only. Normally, + `gprof' prints annotated source files to standard-output. If this + option is specified, annotated source for a file named + `path/FILENAME' is generated in the file `FILENAME-ann'. If the + underlying file system would truncate `FILENAME-ann' so that it + overwrites the original `FILENAME', `gprof' generates annotated + source in the file `FILENAME.ann' instead (if the original file + name has an extension, that extension is _replaced_ with `.ann'). + +`-Z[SYMSPEC]' +`--no-exec-counts[=SYMSPEC]' + The `-Z' option causes `gprof' not to print a tally of functions + and the number of times each was called. If SYMSPEC is specified, + print tally, but exclude matching symbols. + +`-r' +`--function-ordering' + The `--function-ordering' option causes `gprof' to print a + suggested function ordering for the program based on profiling + data. This option suggests an ordering which may improve paging, + tlb and cache behavior for the program on systems which support + arbitrary ordering of functions in an executable. + + The exact details of how to force the linker to place functions in + a particular order is system dependent and out of the scope of this + manual. + +`-R MAP_FILE' +`--file-ordering MAP_FILE' + The `--file-ordering' option causes `gprof' to print a suggested + .o link line ordering for the program based on profiling data. + This option suggests an ordering which may improve paging, tlb and + cache behavior for the program on systems which do not support + arbitrary ordering of functions in an executable. + + Use of the `-a' argument is highly recommended with this option. + + The MAP_FILE argument is a pathname to a file which provides + function name to object file mappings. The format of the file is + similar to the output of the program `nm'. + + c-parse.o:00000000 T yyparse + c-parse.o:00000004 C yyerrflag + c-lang.o:00000000 T maybe_objc_method_name + c-lang.o:00000000 T print_lang_statistics + c-lang.o:00000000 T recognize_objc_keyword + c-decl.o:00000000 T print_lang_identifier + c-decl.o:00000000 T print_lang_type + ... + + To create a MAP_FILE with GNU `nm', type a command like `nm + --extern-only --defined-only -v --print-file-name program-name'. + +`-T' +`--traditional' + The `-T' option causes `gprof' to print its output in + "traditional" BSD style. + +`-w WIDTH' +`--width=WIDTH' + Sets width of output lines to WIDTH. Currently only used when + printing the function index at the bottom of the call graph. + +`-x' +`--all-lines' + This option affects annotated source output only. By default, + only the lines at the beginning of a basic-block are annotated. + If this option is specified, every line in a basic-block is + annotated by repeating the annotation for the first line. This + behavior is similar to `tcov''s `-a'. + +`--demangle[=STYLE]' +`--no-demangle' + These options control whether C++ symbol names should be demangled + when printing output. The default is to demangle symbols. The + `--no-demangle' option may be used to turn off demangling. + Different compilers have different mangling styles. The optional + demangling style argument can be used to choose an appropriate + demangling style for your compiler. + + +File: gprof.info, Node: Analysis Options, Next: Miscellaneous Options, Prev: Output Options, Up: Invoking + +4.2 Analysis Options +==================== + +`-a' +`--no-static' + The `-a' option causes `gprof' to suppress the printing of + statically declared (private) functions. (These are functions + whose names are not listed as global, and which are not visible + outside the file/function/block where they were defined.) Time + spent in these functions, calls to/from them, etc., will all be + attributed to the function that was loaded directly before it in + the executable file. This option affects both the flat profile + and the call graph. + +`-c' +`--static-call-graph' + The `-c' option causes the call graph of the program to be + augmented by a heuristic which examines the text space of the + object file and identifies function calls in the binary machine + code. Since normal call graph records are only generated when + functions are entered, this option identifies children that could + have been called, but never were. Calls to functions that were + not compiled with profiling enabled are also identified, but only + if symbol table entries are present for them. Calls to dynamic + library routines are typically _not_ found by this option. + Parents or children identified via this heuristic are indicated in + the call graph with call counts of `0'. + +`-D' +`--ignore-non-functions' + The `-D' option causes `gprof' to ignore symbols which are not + known to be functions. This option will give more accurate + profile data on systems where it is supported (Solaris and HPUX for + example). + +`-k FROM/TO' + The `-k' option allows you to delete from the call graph any arcs + from symbols matching symspec FROM to those matching symspec TO. + +`-l' +`--line' + The `-l' option enables line-by-line profiling, which causes + histogram hits to be charged to individual source code lines, + instead of functions. This feature only works with programs + compiled by older versions of the `gcc' compiler. Newer versions + of `gcc' are designed to work with the `gcov' tool instead. + + If the program was compiled with basic-block counting enabled, + this option will also identify how many times each line of code + was executed. While line-by-line profiling can help isolate where + in a large function a program is spending its time, it also + significantly increases the running time of `gprof', and magnifies + statistical inaccuracies. *Note Statistical Sampling Error: + Sampling Error. + +`-m NUM' +`--min-count=NUM' + This option affects execution count output only. Symbols that are + executed less than NUM times are suppressed. + +`-nSYMSPEC' +`--time=SYMSPEC' + The `-n' option causes `gprof', in its call graph analysis, to + only propagate times for symbols matching SYMSPEC. + +`-NSYMSPEC' +`--no-time=SYMSPEC' + The `-n' option causes `gprof', in its call graph analysis, not to + propagate times for symbols matching SYMSPEC. + +`-SFILENAME' +`--external-symbol-table=FILENAME' + The `-S' option causes `gprof' to read an external symbol table + file, such as `/proc/kallsyms', rather than read the symbol table + from the given object file (the default is `a.out'). This is useful + for profiling kernel modules. + +`-z' +`--display-unused-functions' + If you give the `-z' option, `gprof' will mention all functions in + the flat profile, even those that were never called, and that had + no time spent in them. This is useful in conjunction with the + `-c' option for discovering which routines were never called. + + + +File: gprof.info, Node: Miscellaneous Options, Next: Deprecated Options, Prev: Analysis Options, Up: Invoking + +4.3 Miscellaneous Options +========================= + +`-d[NUM]' +`--debug[=NUM]' + The `-d NUM' option specifies debugging options. If NUM is not + specified, enable all debugging. *Note Debugging `gprof': + Debugging. + +`-h' +`--help' + The `-h' option prints command line usage. + +`-ONAME' +`--file-format=NAME' + Selects the format of the profile data files. Recognized formats + are `auto' (the default), `bsd', `4.4bsd', `magic', and `prof' + (not yet supported). + +`-s' +`--sum' + The `-s' option causes `gprof' to summarize the information in the + profile data files it read in, and write out a profile data file + called `gmon.sum', which contains all the information from the + profile data files that `gprof' read in. The file `gmon.sum' may + be one of the specified input files; the effect of this is to + merge the data in the other input files into `gmon.sum'. + + Eventually you can run `gprof' again without `-s' to analyze the + cumulative data in the file `gmon.sum'. + +`-v' +`--version' + The `-v' flag causes `gprof' to print the current version number, + and then exit. + + + +File: gprof.info, Node: Deprecated Options, Next: Symspecs, Prev: Miscellaneous Options, Up: Invoking + +4.4 Deprecated Options +====================== + + These options have been replaced with newer versions that use + symspecs. + +`-e FUNCTION_NAME' + The `-e FUNCTION' option tells `gprof' to not print information + about the function FUNCTION_NAME (and its children...) in the call + graph. The function will still be listed as a child of any + functions that call it, but its index number will be shown as + `[not printed]'. More than one `-e' option may be given; only one + FUNCTION_NAME may be indicated with each `-e' option. + +`-E FUNCTION_NAME' + The `-E FUNCTION' option works like the `-e' option, but time + spent in the function (and children who were not called from + anywhere else), will not be used to compute the + percentages-of-time for the call graph. More than one `-E' option + may be given; only one FUNCTION_NAME may be indicated with each + `-E' option. + +`-f FUNCTION_NAME' + The `-f FUNCTION' option causes `gprof' to limit the call graph to + the function FUNCTION_NAME and its children (and their + children...). More than one `-f' option may be given; only one + FUNCTION_NAME may be indicated with each `-f' option. + +`-F FUNCTION_NAME' + The `-F FUNCTION' option works like the `-f' option, but only time + spent in the function and its children (and their children...) + will be used to determine total-time and percentages-of-time for + the call graph. More than one `-F' option may be given; only one + FUNCTION_NAME may be indicated with each `-F' option. The `-F' + option overrides the `-E' option. + + + Note that only one function can be specified with each `-e', `-E', +`-f' or `-F' option. To specify more than one function, use multiple +options. For example, this command: + + gprof -e boring -f foo -f bar myprogram > gprof.output + +lists in the call graph all functions that were reached from either +`foo' or `bar' and were not reachable from `boring'. + + +File: gprof.info, Node: Symspecs, Prev: Deprecated Options, Up: Invoking + +4.5 Symspecs +============ + +Many of the output options allow functions to be included or excluded +using "symspecs" (symbol specifications), which observe the following +syntax: + + filename_containing_a_dot + | funcname_not_containing_a_dot + | linenumber + | ( [ any_filename ] `:' ( any_funcname | linenumber ) ) + + Here are some sample symspecs: + +`main.c' + Selects everything in file `main.c'--the dot in the string tells + `gprof' to interpret the string as a filename, rather than as a + function name. To select a file whose name does not contain a + dot, a trailing colon should be specified. For example, `odd:' is + interpreted as the file named `odd'. + +`main' + Selects all functions named `main'. + + Note that there may be multiple instances of the same function name + because some of the definitions may be local (i.e., static). + Unless a function name is unique in a program, you must use the + colon notation explained below to specify a function from a + specific source file. + + Sometimes, function names contain dots. In such cases, it is + necessary to add a leading colon to the name. For example, + `:.mul' selects function `.mul'. + + In some object file formats, symbols have a leading underscore. + `gprof' will normally not print these underscores. When you name a + symbol in a symspec, you should type it exactly as `gprof' prints + it in its output. For example, if the compiler produces a symbol + `_main' from your `main' function, `gprof' still prints it as + `main' in its output, so you should use `main' in symspecs. + +`main.c:main' + Selects function `main' in file `main.c'. + +`main.c:134' + Selects line 134 in file `main.c'. + + +File: gprof.info, Node: Output, Next: Inaccuracy, Prev: Invoking, Up: Top + +5 Interpreting `gprof''s Output +******************************* + +`gprof' can produce several different output styles, the most important +of which are described below. The simplest output styles (file +information, execution count, and function and file ordering) are not +described here, but are documented with the respective options that +trigger them. *Note Output Options: Output Options. + +* Menu: + +* Flat Profile:: The flat profile shows how much time was spent + executing directly in each function. +* Call Graph:: The call graph shows which functions called which + others, and how much time each function used + when its subroutine calls are included. +* Line-by-line:: `gprof' can analyze individual source code lines +* Annotated Source:: The annotated source listing displays source code + labeled with execution counts + + +File: gprof.info, Node: Flat Profile, Next: Call Graph, Up: Output + +5.1 The Flat Profile +==================== + +The "flat profile" shows the total amount of time your program spent +executing each function. Unless the `-z' option is given, functions +with no apparent time spent in them, and no apparent calls to them, are +not mentioned. Note that if a function was not compiled for profiling, +and didn't run long enough to show up on the program counter histogram, +it will be indistinguishable from a function that was never called. + + This is part of a flat profile for a small program: + + Flat profile: + + Each sample counts as 0.01 seconds. + % cumulative self self total + time seconds seconds calls ms/call ms/call name + 33.34 0.02 0.02 7208 0.00 0.00 open + 16.67 0.03 0.01 244 0.04 0.12 offtime + 16.67 0.04 0.01 8 1.25 1.25 memccpy + 16.67 0.05 0.01 7 1.43 1.43 write + 16.67 0.06 0.01 mcount + 0.00 0.06 0.00 236 0.00 0.00 tzset + 0.00 0.06 0.00 192 0.00 0.00 tolower + 0.00 0.06 0.00 47 0.00 0.00 strlen + 0.00 0.06 0.00 45 0.00 0.00 strchr + 0.00 0.06 0.00 1 0.00 50.00 main + 0.00 0.06 0.00 1 0.00 0.00 memcpy + 0.00 0.06 0.00 1 0.00 10.11 print + 0.00 0.06 0.00 1 0.00 0.00 profil + 0.00 0.06 0.00 1 0.00 50.00 report + ... + +The functions are sorted first by decreasing run-time spent in them, +then by decreasing number of calls, then alphabetically by name. The +functions `mcount' and `profil' are part of the profiling apparatus and +appear in every flat profile; their time gives a measure of the amount +of overhead due to profiling. + + Just before the column headers, a statement appears indicating how +much time each sample counted as. This "sampling period" estimates the +margin of error in each of the time figures. A time figure that is not +much larger than this is not reliable. In this example, each sample +counted as 0.01 seconds, suggesting a 100 Hz sampling rate. The +program's total execution time was 0.06 seconds, as indicated by the +`cumulative seconds' field. Since each sample counted for 0.01 +seconds, this means only six samples were taken during the run. Two of +the samples occurred while the program was in the `open' function, as +indicated by the `self seconds' field. Each of the other four samples +occurred one each in `offtime', `memccpy', `write', and `mcount'. +Since only six samples were taken, none of these values can be regarded +as particularly reliable. In another run, the `self seconds' field for +`mcount' might well be `0.00' or `0.02'. *Note Statistical Sampling +Error: Sampling Error, for a complete discussion. + + The remaining functions in the listing (those whose `self seconds' +field is `0.00') didn't appear in the histogram samples at all. +However, the call graph indicated that they were called, so therefore +they are listed, sorted in decreasing order by the `calls' field. +Clearly some time was spent executing these functions, but the paucity +of histogram samples prevents any determination of how much time each +took. + + Here is what the fields in each line mean: + +`% time' + This is the percentage of the total execution time your program + spent in this function. These should all add up to 100%. + +`cumulative seconds' + This is the cumulative total number of seconds the computer spent + executing this functions, plus the time spent in all the functions + above this one in this table. + +`self seconds' + This is the number of seconds accounted for by this function alone. + The flat profile listing is sorted first by this number. + +`calls' + This is the total number of times the function was called. If the + function was never called, or the number of times it was called + cannot be determined (probably because the function was not + compiled with profiling enabled), the "calls" field is blank. + +`self ms/call' + This represents the average number of milliseconds spent in this + function per call, if this function is profiled. Otherwise, this + field is blank for this function. + +`total ms/call' + This represents the average number of milliseconds spent in this + function and its descendants per call, if this function is + profiled. Otherwise, this field is blank for this function. This + is the only field in the flat profile that uses call graph + analysis. + +`name' + This is the name of the function. The flat profile is sorted by + this field alphabetically after the "self seconds" and "calls" + fields are sorted. + + +File: gprof.info, Node: Call Graph, Next: Line-by-line, Prev: Flat Profile, Up: Output + +5.2 The Call Graph +================== + +The "call graph" shows how much time was spent in each function and its +children. From this information, you can find functions that, while +they themselves may not have used much time, called other functions +that did use unusual amounts of time. + + Here is a sample call from a small program. This call came from the +same `gprof' run as the flat profile example in the previous section. + + granularity: each sample hit covers 2 byte(s) for 20.00% of 0.05 seconds + + index % time self children called name + <spontaneous> + [1] 100.0 0.00 0.05 start [1] + 0.00 0.05 1/1 main [2] + 0.00 0.00 1/2 on_exit [28] + 0.00 0.00 1/1 exit [59] + ----------------------------------------------- + 0.00 0.05 1/1 start [1] + [2] 100.0 0.00 0.05 1 main [2] + 0.00 0.05 1/1 report [3] + ----------------------------------------------- + 0.00 0.05 1/1 main [2] + [3] 100.0 0.00 0.05 1 report [3] + 0.00 0.03 8/8 timelocal [6] + 0.00 0.01 1/1 print [9] + 0.00 0.01 9/9 fgets [12] + 0.00 0.00 12/34 strncmp <cycle 1> [40] + 0.00 0.00 8/8 lookup [20] + 0.00 0.00 1/1 fopen [21] + 0.00 0.00 8/8 chewtime [24] + 0.00 0.00 8/16 skipspace [44] + ----------------------------------------------- + [4] 59.8 0.01 0.02 8+472 <cycle 2 as a whole> [4] + 0.01 0.02 244+260 offtime <cycle 2> [7] + 0.00 0.00 236+1 tzset <cycle 2> [26] + ----------------------------------------------- + + The lines full of dashes divide this table into "entries", one for +each function. Each entry has one or more lines. + + In each entry, the primary line is the one that starts with an index +number in square brackets. The end of this line says which function +the entry is for. The preceding lines in the entry describe the +callers of this function and the following lines describe its +subroutines (also called "children" when we speak of the call graph). + + The entries are sorted by time spent in the function and its +subroutines. + + The internal profiling function `mcount' (*note The Flat Profile: +Flat Profile.) is never mentioned in the call graph. + +* Menu: + +* Primary:: Details of the primary line's contents. +* Callers:: Details of caller-lines' contents. +* Subroutines:: Details of subroutine-lines' contents. +* Cycles:: When there are cycles of recursion, + such as `a' calls `b' calls `a'... + + +File: gprof.info, Node: Primary, Next: Callers, Up: Call Graph + +5.2.1 The Primary Line +---------------------- + +The "primary line" in a call graph entry is the line that describes the +function which the entry is about and gives the overall statistics for +this function. + + For reference, we repeat the primary line from the entry for function +`report' in our main example, together with the heading line that shows +the names of the fields: + + index % time self children called name + ... + [3] 100.0 0.00 0.05 1 report [3] + + Here is what the fields in the primary line mean: + +`index' + Entries are numbered with consecutive integers. Each function + therefore has an index number, which appears at the beginning of + its primary line. + + Each cross-reference to a function, as a caller or subroutine of + another, gives its index number as well as its name. The index + number guides you if you wish to look for the entry for that + function. + +`% time' + This is the percentage of the total time that was spent in this + function, including time spent in subroutines called from this + function. + + The time spent in this function is counted again for the callers of + this function. Therefore, adding up these percentages is + meaningless. + +`self' + This is the total amount of time spent in this function. This + should be identical to the number printed in the `seconds' field + for this function in the flat profile. + +`children' + This is the total amount of time spent in the subroutine calls + made by this function. This should be equal to the sum of all the + `self' and `children' entries of the children listed directly + below this function. + +`called' + This is the number of times the function was called. + + If the function called itself recursively, there are two numbers, + separated by a `+'. The first number counts non-recursive calls, + and the second counts recursive calls. + + In the example above, the function `report' was called once from + `main'. + +`name' + This is the name of the current function. The index number is + repeated after it. + + If the function is part of a cycle of recursion, the cycle number + is printed between the function's name and the index number (*note + How Mutually Recursive Functions Are Described: Cycles.). For + example, if function `gnurr' is part of cycle number one, and has + index number twelve, its primary line would be end like this: + + gnurr <cycle 1> [12] + + +File: gprof.info, Node: Callers, Next: Subroutines, Prev: Primary, Up: Call Graph + +5.2.2 Lines for a Function's Callers +------------------------------------ + +A function's entry has a line for each function it was called by. +These lines' fields correspond to the fields of the primary line, but +their meanings are different because of the difference in context. + + For reference, we repeat two lines from the entry for the function +`report', the primary line and one caller-line preceding it, together +with the heading line that shows the names of the fields: + + index % time self children called name + ... + 0.00 0.05 1/1 main [2] + [3] 100.0 0.00 0.05 1 report [3] + + Here are the meanings of the fields in the caller-line for `report' +called from `main': + +`self' + An estimate of the amount of time spent in `report' itself when it + was called from `main'. + +`children' + An estimate of the amount of time spent in subroutines of `report' + when `report' was called from `main'. + + The sum of the `self' and `children' fields is an estimate of the + amount of time spent within calls to `report' from `main'. + +`called' + Two numbers: the number of times `report' was called from `main', + followed by the total number of non-recursive calls to `report' + from all its callers. + +`name and index number' + The name of the caller of `report' to which this line applies, + followed by the caller's index number. + + Not all functions have entries in the call graph; some options to + `gprof' request the omission of certain functions. When a caller + has no entry of its own, it still has caller-lines in the entries + of the functions it calls. + + If the caller is part of a recursion cycle, the cycle number is + printed between the name and the index number. + + If the identity of the callers of a function cannot be determined, a +dummy caller-line is printed which has `<spontaneous>' as the "caller's +name" and all other fields blank. This can happen for signal handlers. + + +File: gprof.info, Node: Subroutines, Next: Cycles, Prev: Callers, Up: Call Graph + +5.2.3 Lines for a Function's Subroutines +---------------------------------------- + +A function's entry has a line for each of its subroutines--in other +words, a line for each other function that it called. These lines' +fields correspond to the fields of the primary line, but their meanings +are different because of the difference in context. + + For reference, we repeat two lines from the entry for the function +`main', the primary line and a line for a subroutine, together with the +heading line that shows the names of the fields: + + index % time self children called name + ... + [2] 100.0 0.00 0.05 1 main [2] + 0.00 0.05 1/1 report [3] + + Here are the meanings of the fields in the subroutine-line for `main' +calling `report': + +`self' + An estimate of the amount of time spent directly within `report' + when `report' was called from `main'. + +`children' + An estimate of the amount of time spent in subroutines of `report' + when `report' was called from `main'. + + The sum of the `self' and `children' fields is an estimate of the + total time spent in calls to `report' from `main'. + +`called' + Two numbers, the number of calls to `report' from `main' followed + by the total number of non-recursive calls to `report'. This + ratio is used to determine how much of `report''s `self' and + `children' time gets credited to `main'. *Note Estimating + `children' Times: Assumptions. + +`name' + The name of the subroutine of `main' to which this line applies, + followed by the subroutine's index number. + + If the caller is part of a recursion cycle, the cycle number is + printed between the name and the index number. + + +File: gprof.info, Node: Cycles, Prev: Subroutines, Up: Call Graph + +5.2.4 How Mutually Recursive Functions Are Described +---------------------------------------------------- + +The graph may be complicated by the presence of "cycles of recursion" +in the call graph. A cycle exists if a function calls another function +that (directly or indirectly) calls (or appears to call) the original +function. For example: if `a' calls `b', and `b' calls `a', then `a' +and `b' form a cycle. + + Whenever there are call paths both ways between a pair of functions, +they belong to the same cycle. If `a' and `b' call each other and `b' +and `c' call each other, all three make one cycle. Note that even if +`b' only calls `a' if it was not called from `a', `gprof' cannot +determine this, so `a' and `b' are still considered a cycle. + + The cycles are numbered with consecutive integers. When a function +belongs to a cycle, each time the function name appears in the call +graph it is followed by `<cycle NUMBER>'. + + The reason cycles matter is that they make the time values in the +call graph paradoxical. The "time spent in children" of `a' should +include the time spent in its subroutine `b' and in `b''s +subroutines--but one of `b''s subroutines is `a'! How much of `a''s +time should be included in the children of `a', when `a' is indirectly +recursive? + + The way `gprof' resolves this paradox is by creating a single entry +for the cycle as a whole. The primary line of this entry describes the +total time spent directly in the functions of the cycle. The +"subroutines" of the cycle are the individual functions of the cycle, +and all other functions that were called directly by them. The +"callers" of the cycle are the functions, outside the cycle, that +called functions in the cycle. + + Here is an example portion of a call graph which shows a cycle +containing functions `a' and `b'. The cycle was entered by a call to +`a' from `main'; both `a' and `b' called `c'. + + index % time self children called name + ---------------------------------------- + 1.77 0 1/1 main [2] + [3] 91.71 1.77 0 1+5 <cycle 1 as a whole> [3] + 1.02 0 3 b <cycle 1> [4] + 0.75 0 2 a <cycle 1> [5] + ---------------------------------------- + 3 a <cycle 1> [5] + [4] 52.85 1.02 0 0 b <cycle 1> [4] + 2 a <cycle 1> [5] + 0 0 3/6 c [6] + ---------------------------------------- + 1.77 0 1/1 main [2] + 2 b <cycle 1> [4] + [5] 38.86 0.75 0 1 a <cycle 1> [5] + 3 b <cycle 1> [4] + 0 0 3/6 c [6] + ---------------------------------------- + +(The entire call graph for this program contains in addition an entry +for `main', which calls `a', and an entry for `c', with callers `a' and +`b'.) + + index % time self children called name + <spontaneous> + [1] 100.00 0 1.93 0 start [1] + 0.16 1.77 1/1 main [2] + ---------------------------------------- + 0.16 1.77 1/1 start [1] + [2] 100.00 0.16 1.77 1 main [2] + 1.77 0 1/1 a <cycle 1> [5] + ---------------------------------------- + 1.77 0 1/1 main [2] + [3] 91.71 1.77 0 1+5 <cycle 1 as a whole> [3] + 1.02 0 3 b <cycle 1> [4] + 0.75 0 2 a <cycle 1> [5] + 0 0 6/6 c [6] + ---------------------------------------- + 3 a <cycle 1> [5] + [4] 52.85 1.02 0 0 b <cycle 1> [4] + 2 a <cycle 1> [5] + 0 0 3/6 c [6] + ---------------------------------------- + 1.77 0 1/1 main [2] + 2 b <cycle 1> [4] + [5] 38.86 0.75 0 1 a <cycle 1> [5] + 3 b <cycle 1> [4] + 0 0 3/6 c [6] + ---------------------------------------- + 0 0 3/6 b <cycle 1> [4] + 0 0 3/6 a <cycle 1> [5] + [6] 0.00 0 0 6 c [6] + ---------------------------------------- + + The `self' field of the cycle's primary line is the total time spent +in all the functions of the cycle. It equals the sum of the `self' +fields for the individual functions in the cycle, found in the entry in +the subroutine lines for these functions. + + The `children' fields of the cycle's primary line and subroutine +lines count only subroutines outside the cycle. Even though `a' calls +`b', the time spent in those calls to `b' is not counted in `a''s +`children' time. Thus, we do not encounter the problem of what to do +when the time in those calls to `b' includes indirect recursive calls +back to `a'. + + The `children' field of a caller-line in the cycle's entry estimates +the amount of time spent _in the whole cycle_, and its other +subroutines, on the times when that caller called a function in the +cycle. + + The `called' field in the primary line for the cycle has two numbers: +first, the number of times functions in the cycle were called by +functions outside the cycle; second, the number of times they were +called by functions in the cycle (including times when a function in +the cycle calls itself). This is a generalization of the usual split +into non-recursive and recursive calls. + + The `called' field of a subroutine-line for a cycle member in the +cycle's entry says how many time that function was called from +functions in the cycle. The total of all these is the second number in +the primary line's `called' field. + + In the individual entry for a function in a cycle, the other +functions in the same cycle can appear as subroutines and as callers. +These lines show how many times each function in the cycle called or +was called from each other function in the cycle. The `self' and +`children' fields in these lines are blank because of the difficulty of +defining meanings for them when recursion is going on. + + +File: gprof.info, Node: Line-by-line, Next: Annotated Source, Prev: Call Graph, Up: Output + +5.3 Line-by-line Profiling +========================== + +`gprof''s `-l' option causes the program to perform "line-by-line" +profiling. In this mode, histogram samples are assigned not to +functions, but to individual lines of source code. This only works +with programs compiled with older versions of the `gcc' compiler. +Newer versions of `gcc' use a different program - `gcov' - to display +line-by-line profiling information. + + With the older versions of `gcc' the program usually has to be +compiled with a `-g' option, in addition to `-pg', in order to generate +debugging symbols for tracking source code lines. Note, in much older +versions of `gcc' the program had to be compiled with the `-a' command +line option as well. + + The flat profile is the most useful output table in line-by-line +mode. The call graph isn't as useful as normal, since the current +version of `gprof' does not propagate call graph arcs from source code +lines to the enclosing function. The call graph does, however, show +each line of code that called each function, along with a count. + + Here is a section of `gprof''s output, without line-by-line +profiling. Note that `ct_init' accounted for four histogram hits, and +13327 calls to `init_block'. + + Flat profile: + + Each sample counts as 0.01 seconds. + % cumulative self self total + time seconds seconds calls us/call us/call name + 30.77 0.13 0.04 6335 6.31 6.31 ct_init + + + Call graph (explanation follows) + + + granularity: each sample hit covers 4 byte(s) for 7.69% of 0.13 seconds + + index % time self children called name + + 0.00 0.00 1/13496 name_too_long + 0.00 0.00 40/13496 deflate + 0.00 0.00 128/13496 deflate_fast + 0.00 0.00 13327/13496 ct_init + [7] 0.0 0.00 0.00 13496 init_block + + Now let's look at some of `gprof''s output from the same program run, +this time with line-by-line profiling enabled. Note that `ct_init''s +four histogram hits are broken down into four lines of source code--one +hit occurred on each of lines 349, 351, 382 and 385. In the call graph, +note how `ct_init''s 13327 calls to `init_block' are broken down into +one call from line 396, 3071 calls from line 384, 3730 calls from line +385, and 6525 calls from 387. + + Flat profile: + + Each sample counts as 0.01 seconds. + % cumulative self + time seconds seconds calls name + 7.69 0.10 0.01 ct_init (trees.c:349) + 7.69 0.11 0.01 ct_init (trees.c:351) + 7.69 0.12 0.01 ct_init (trees.c:382) + 7.69 0.13 0.01 ct_init (trees.c:385) + + + Call graph (explanation follows) + + + granularity: each sample hit covers 4 byte(s) for 7.69% of 0.13 seconds + + % time self children called name + + 0.00 0.00 1/13496 name_too_long (gzip.c:1440) + 0.00 0.00 1/13496 deflate (deflate.c:763) + 0.00 0.00 1/13496 ct_init (trees.c:396) + 0.00 0.00 2/13496 deflate (deflate.c:727) + 0.00 0.00 4/13496 deflate (deflate.c:686) + 0.00 0.00 5/13496 deflate (deflate.c:675) + 0.00 0.00 12/13496 deflate (deflate.c:679) + 0.00 0.00 16/13496 deflate (deflate.c:730) + 0.00 0.00 128/13496 deflate_fast (deflate.c:654) + 0.00 0.00 3071/13496 ct_init (trees.c:384) + 0.00 0.00 3730/13496 ct_init (trees.c:385) + 0.00 0.00 6525/13496 ct_init (trees.c:387) + [6] 0.0 0.00 0.00 13496 init_block (trees.c:408) + + +File: gprof.info, Node: Annotated Source, Prev: Line-by-line, Up: Output + +5.4 The Annotated Source Listing +================================ + +`gprof''s `-A' option triggers an annotated source listing, which lists +the program's source code, each function labeled with the number of +times it was called. You may also need to specify the `-I' option, if +`gprof' can't find the source code files. + + With older versions of `gcc' compiling with `gcc ... -g -pg -a' +augments your program with basic-block counting code, in addition to +function counting code. This enables `gprof' to determine how many +times each line of code was executed. With newer versions of `gcc' +support for displaying basic-block counts is provided by the `gcov' +program. + + For example, consider the following function, taken from gzip, with +line numbers added: + + 1 ulg updcrc(s, n) + 2 uch *s; + 3 unsigned n; + 4 { + 5 register ulg c; + 6 + 7 static ulg crc = (ulg)0xffffffffL; + 8 + 9 if (s == NULL) { + 10 c = 0xffffffffL; + 11 } else { + 12 c = crc; + 13 if (n) do { + 14 c = crc_32_tab[...]; + 15 } while (--n); + 16 } + 17 crc = c; + 18 return c ^ 0xffffffffL; + 19 } + + `updcrc' has at least five basic-blocks. One is the function +itself. The `if' statement on line 9 generates two more basic-blocks, +one for each branch of the `if'. A fourth basic-block results from the +`if' on line 13, and the contents of the `do' loop form the fifth +basic-block. The compiler may also generate additional basic-blocks to +handle various special cases. + + A program augmented for basic-block counting can be analyzed with +`gprof -l -A'. The `-x' option is also helpful, to ensure that each +line of code is labeled at least once. Here is `updcrc''s annotated +source listing for a sample `gzip' run: + + ulg updcrc(s, n) + uch *s; + unsigned n; + 2 ->{ + register ulg c; + + static ulg crc = (ulg)0xffffffffL; + + 2 -> if (s == NULL) { + 1 -> c = 0xffffffffL; + 1 -> } else { + 1 -> c = crc; + 1 -> if (n) do { + 26312 -> c = crc_32_tab[...]; + 26312,1,26311 -> } while (--n); + } + 2 -> crc = c; + 2 -> return c ^ 0xffffffffL; + 2 ->} + + In this example, the function was called twice, passing once through +each branch of the `if' statement. The body of the `do' loop was +executed a total of 26312 times. Note how the `while' statement is +annotated. It began execution 26312 times, once for each iteration +through the loop. One of those times (the last time) it exited, while +it branched back to the beginning of the loop 26311 times. + + +File: gprof.info, Node: Inaccuracy, Next: How do I?, Prev: Output, Up: Top + +6 Inaccuracy of `gprof' Output +****************************** + +* Menu: + +* Sampling Error:: Statistical margins of error +* Assumptions:: Estimating children times + + +File: gprof.info, Node: Sampling Error, Next: Assumptions, Up: Inaccuracy + +6.1 Statistical Sampling Error +============================== + +The run-time figures that `gprof' gives you are based on a sampling +process, so they are subject to statistical inaccuracy. If a function +runs only a small amount of time, so that on the average the sampling +process ought to catch that function in the act only once, there is a +pretty good chance it will actually find that function zero times, or +twice. + + By contrast, the number-of-calls and basic-block figures are derived +by counting, not sampling. They are completely accurate and will not +vary from run to run if your program is deterministic. + + The "sampling period" that is printed at the beginning of the flat +profile says how often samples are taken. The rule of thumb is that a +run-time figure is accurate if it is considerably bigger than the +sampling period. + + The actual amount of error can be predicted. For N samples, the +_expected_ error is the square-root of N. For example, if the sampling +period is 0.01 seconds and `foo''s run-time is 1 second, N is 100 +samples (1 second/0.01 seconds), sqrt(N) is 10 samples, so the expected +error in `foo''s run-time is 0.1 seconds (10*0.01 seconds), or ten +percent of the observed value. Again, if the sampling period is 0.01 +seconds and `bar''s run-time is 100 seconds, N is 10000 samples, +sqrt(N) is 100 samples, so the expected error in `bar''s run-time is 1 +second, or one percent of the observed value. It is likely to vary +this much _on the average_ from one profiling run to the next. +(_Sometimes_ it will vary more.) + + This does not mean that a small run-time figure is devoid of +information. If the program's _total_ run-time is large, a small +run-time for one function does tell you that that function used an +insignificant fraction of the whole program's time. Usually this means +it is not worth optimizing. + + One way to get more accuracy is to give your program more (but +similar) input data so it will take longer. Another way is to combine +the data from several runs, using the `-s' option of `gprof'. Here is +how: + + 1. Run your program once. + + 2. Issue the command `mv gmon.out gmon.sum'. + + 3. Run your program again, the same as before. + + 4. Merge the new data in `gmon.out' into `gmon.sum' with this command: + + gprof -s EXECUTABLE-FILE gmon.out gmon.sum + + 5. Repeat the last two steps as often as you wish. + + 6. Analyze the cumulative data using this command: + + gprof EXECUTABLE-FILE gmon.sum > OUTPUT-FILE + + +File: gprof.info, Node: Assumptions, Prev: Sampling Error, Up: Inaccuracy + +6.2 Estimating `children' Times +=============================== + +Some of the figures in the call graph are estimates--for example, the +`children' time values and all the time figures in caller and +subroutine lines. + + There is no direct information about these measurements in the +profile data itself. Instead, `gprof' estimates them by making an +assumption about your program that might or might not be true. + + The assumption made is that the average time spent in each call to +any function `foo' is not correlated with who called `foo'. If `foo' +used 5 seconds in all, and 2/5 of the calls to `foo' came from `a', +then `foo' contributes 2 seconds to `a''s `children' time, by +assumption. + + This assumption is usually true enough, but for some programs it is +far from true. Suppose that `foo' returns very quickly when its +argument is zero; suppose that `a' always passes zero as an argument, +while other callers of `foo' pass other arguments. In this program, +all the time spent in `foo' is in the calls from callers other than `a'. +But `gprof' has no way of knowing this; it will blindly and incorrectly +charge 2 seconds of time in `foo' to the children of `a'. + + We hope some day to put more complete data into `gmon.out', so that +this assumption is no longer needed, if we can figure out how. For the +novice, the estimated figures are usually more useful than misleading. + + +File: gprof.info, Node: How do I?, Next: Incompatibilities, Prev: Inaccuracy, Up: Top + +7 Answers to Common Questions +***************************** + +How can I get more exact information about hot spots in my program? + Looking at the per-line call counts only tells part of the story. + Because `gprof' can only report call times and counts by function, + the best way to get finer-grained information on where the program + is spending its time is to re-factor large functions into sequences + of calls to smaller ones. Beware however that this can introduce + artificial hot spots since compiling with `-pg' adds a significant + overhead to function calls. An alternative solution is to use a + non-intrusive profiler, e.g. oprofile. + +How do I find which lines in my program were executed the most times? + Use the `gcov' program. + +How do I find which lines in my program called a particular function? + Use `gprof -l' and lookup the function in the call graph. The + callers will be broken down by function and line number. + +How do I analyze a program that runs for less than a second? + Try using a shell script like this one: + + for i in `seq 1 100`; do + fastprog + mv gmon.out gmon.out.$i + done + + gprof -s fastprog gmon.out.* + + gprof fastprog gmon.sum + + If your program is completely deterministic, all the call counts + will be simple multiples of 100 (i.e., a function called once in + each run will appear with a call count of 100). + + + +File: gprof.info, Node: Incompatibilities, Next: Details, Prev: How do I?, Up: Top + +8 Incompatibilities with Unix `gprof' +************************************* + +GNU `gprof' and Berkeley Unix `gprof' use the same data file +`gmon.out', and provide essentially the same information. But there +are a few differences. + + * GNU `gprof' uses a new, generalized file format with support for + basic-block execution counts and non-realtime histograms. A magic + cookie and version number allows `gprof' to easily identify new + style files. Old BSD-style files can still be read. *Note + Profiling Data File Format: File Format. + + * For a recursive function, Unix `gprof' lists the function as a + parent and as a child, with a `calls' field that lists the number + of recursive calls. GNU `gprof' omits these lines and puts the + number of recursive calls in the primary line. + + * When a function is suppressed from the call graph with `-e', GNU + `gprof' still lists it as a subroutine of functions that call it. + + * GNU `gprof' accepts the `-k' with its argument in the form + `from/to', instead of `from to'. + + * In the annotated source listing, if there are multiple basic + blocks on the same line, GNU `gprof' prints all of their counts, + separated by commas. + + * The blurbs, field widths, and output formats are different. GNU + `gprof' prints blurbs after the tables, so that you can see the + tables without skipping the blurbs. + + +File: gprof.info, Node: Details, Next: GNU Free Documentation License, Prev: Incompatibilities, Up: Top + +9 Details of Profiling +********************** + +* Menu: + +* Implementation:: How a program collects profiling information +* File Format:: Format of `gmon.out' files +* Internals:: `gprof''s internal operation +* Debugging:: Using `gprof''s `-d' option + + +File: gprof.info, Node: Implementation, Next: File Format, Up: Details + +9.1 Implementation of Profiling +=============================== + +Profiling works by changing how every function in your program is +compiled so that when it is called, it will stash away some information +about where it was called from. From this, the profiler can figure out +what function called it, and can count how many times it was called. +This change is made by the compiler when your program is compiled with +the `-pg' option, which causes every function to call `mcount' (or +`_mcount', or `__mcount', depending on the OS and compiler) as one of +its first operations. + + The `mcount' routine, included in the profiling library, is +responsible for recording in an in-memory call graph table both its +parent routine (the child) and its parent's parent. This is typically +done by examining the stack frame to find both the address of the +child, and the return address in the original parent. Since this is a +very machine-dependent operation, `mcount' itself is typically a short +assembly-language stub routine that extracts the required information, +and then calls `__mcount_internal' (a normal C function) with two +arguments--`frompc' and `selfpc'. `__mcount_internal' is responsible +for maintaining the in-memory call graph, which records `frompc', +`selfpc', and the number of times each of these call arcs was traversed. + + GCC Version 2 provides a magical function +(`__builtin_return_address'), which allows a generic `mcount' function +to extract the required information from the stack frame. However, on +some architectures, most notably the SPARC, using this builtin can be +very computationally expensive, and an assembly language version of +`mcount' is used for performance reasons. + + Number-of-calls information for library routines is collected by +using a special version of the C library. The programs in it are the +same as in the usual C library, but they were compiled with `-pg'. If +you link your program with `gcc ... -pg', it automatically uses the +profiling version of the library. + + Profiling also involves watching your program as it runs, and +keeping a histogram of where the program counter happens to be every +now and then. Typically the program counter is looked at around 100 +times per second of run time, but the exact frequency may vary from +system to system. + + This is done is one of two ways. Most UNIX-like operating systems +provide a `profil()' system call, which registers a memory array with +the kernel, along with a scale factor that determines how the program's +address space maps into the array. Typical scaling values cause every +2 to 8 bytes of address space to map into a single array slot. On +every tick of the system clock (assuming the profiled program is +running), the value of the program counter is examined and the +corresponding slot in the memory array is incremented. Since this is +done in the kernel, which had to interrupt the process anyway to handle +the clock interrupt, very little additional system overhead is required. + + However, some operating systems, most notably Linux 2.0 (and +earlier), do not provide a `profil()' system call. On such a system, +arrangements are made for the kernel to periodically deliver a signal +to the process (typically via `setitimer()'), which then performs the +same operation of examining the program counter and incrementing a slot +in the memory array. Since this method requires a signal to be +delivered to user space every time a sample is taken, it uses +considerably more overhead than kernel-based profiling. Also, due to +the added delay required to deliver the signal, this method is less +accurate as well. + + A special startup routine allocates memory for the histogram and +either calls `profil()' or sets up a clock signal handler. This +routine (`monstartup') can be invoked in several ways. On Linux +systems, a special profiling startup file `gcrt0.o', which invokes +`monstartup' before `main', is used instead of the default `crt0.o'. +Use of this special startup file is one of the effects of using `gcc +... -pg' to link. On SPARC systems, no special startup files are used. +Rather, the `mcount' routine, when it is invoked for the first time +(typically when `main' is called), calls `monstartup'. + + If the compiler's `-a' option was used, basic-block counting is also +enabled. Each object file is then compiled with a static array of +counts, initially zero. In the executable code, every time a new +basic-block begins (i.e., when an `if' statement appears), an extra +instruction is inserted to increment the corresponding count in the +array. At compile time, a paired array was constructed that recorded +the starting address of each basic-block. Taken together, the two +arrays record the starting address of every basic-block, along with the +number of times it was executed. + + The profiling library also includes a function (`mcleanup') which is +typically registered using `atexit()' to be called as the program +exits, and is responsible for writing the file `gmon.out'. Profiling +is turned off, various headers are output, and the histogram is +written, followed by the call-graph arcs and the basic-block counts. + + The output from `gprof' gives no indication of parts of your program +that are limited by I/O or swapping bandwidth. This is because samples +of the program counter are taken at fixed intervals of the program's +run time. Therefore, the time measurements in `gprof' output say +nothing about time that your program was not running. For example, a +part of the program that creates so much data that it cannot all fit in +physical memory at once may run very slowly due to thrashing, but +`gprof' will say it uses little time. On the other hand, sampling by +run time has the advantage that the amount of load due to other users +won't directly affect the output you get. + + +File: gprof.info, Node: File Format, Next: Internals, Prev: Implementation, Up: Details + +9.2 Profiling Data File Format +============================== + +The old BSD-derived file format used for profile data does not contain a +magic cookie that allows to check whether a data file really is a +`gprof' file. Furthermore, it does not provide a version number, thus +rendering changes to the file format almost impossible. GNU `gprof' +uses a new file format that provides these features. For backward +compatibility, GNU `gprof' continues to support the old BSD-derived +format, but not all features are supported with it. For example, +basic-block execution counts cannot be accommodated by the old file +format. + + The new file format is defined in header file `gmon_out.h'. It +consists of a header containing the magic cookie and a version number, +as well as some spare bytes available for future extensions. All data +in a profile data file is in the native format of the target for which +the profile was collected. GNU `gprof' adapts automatically to the +byte-order in use. + + In the new file format, the header is followed by a sequence of +records. Currently, there are three different record types: histogram +records, call-graph arc records, and basic-block execution count +records. Each file can contain any number of each record type. When +reading a file, GNU `gprof' will ensure records of the same type are +compatible with each other and compute the union of all records. For +example, for basic-block execution counts, the union is simply the sum +of all execution counts for each basic-block. + +9.2.1 Histogram Records +----------------------- + +Histogram records consist of a header that is followed by an array of +bins. The header contains the text-segment range that the histogram +spans, the size of the histogram in bytes (unlike in the old BSD +format, this does not include the size of the header), the rate of the +profiling clock, and the physical dimension that the bin counts +represent after being scaled by the profiling clock rate. The physical +dimension is specified in two parts: a long name of up to 15 characters +and a single character abbreviation. For example, a histogram +representing real-time would specify the long name as "seconds" and the +abbreviation as "s". This feature is useful for architectures that +support performance monitor hardware (which, fortunately, is becoming +increasingly common). For example, under DEC OSF/1, the "uprofile" +command can be used to produce a histogram of, say, instruction cache +misses. In this case, the dimension in the histogram header could be +set to "i-cache misses" and the abbreviation could be set to "1" +(because it is simply a count, not a physical dimension). Also, the +profiling rate would have to be set to 1 in this case. + + Histogram bins are 16-bit numbers and each bin represent an equal +amount of text-space. For example, if the text-segment is one thousand +bytes long and if there are ten bins in the histogram, each bin +represents one hundred bytes. + +9.2.2 Call-Graph Records +------------------------ + +Call-graph records have a format that is identical to the one used in +the BSD-derived file format. It consists of an arc in the call graph +and a count indicating the number of times the arc was traversed during +program execution. Arcs are specified by a pair of addresses: the +first must be within caller's function and the second must be within +the callee's function. When performing profiling at the function +level, these addresses can point anywhere within the respective +function. However, when profiling at the line-level, it is better if +the addresses are as close to the call-site/entry-point as possible. +This will ensure that the line-level call-graph is able to identify +exactly which line of source code performed calls to a function. + +9.2.3 Basic-Block Execution Count Records +----------------------------------------- + +Basic-block execution count records consist of a header followed by a +sequence of address/count pairs. The header simply specifies the +length of the sequence. In an address/count pair, the address +identifies a basic-block and the count specifies the number of times +that basic-block was executed. Any address within the basic-address can +be used. + + +File: gprof.info, Node: Internals, Next: Debugging, Prev: File Format, Up: Details + +9.3 `gprof''s Internal Operation +================================ + +Like most programs, `gprof' begins by processing its options. During +this stage, it may building its symspec list (`sym_ids.c:sym_id_add'), +if options are specified which use symspecs. `gprof' maintains a +single linked list of symspecs, which will eventually get turned into +12 symbol tables, organized into six include/exclude pairs--one pair +each for the flat profile (INCL_FLAT/EXCL_FLAT), the call graph arcs +(INCL_ARCS/EXCL_ARCS), printing in the call graph +(INCL_GRAPH/EXCL_GRAPH), timing propagation in the call graph +(INCL_TIME/EXCL_TIME), the annotated source listing +(INCL_ANNO/EXCL_ANNO), and the execution count listing +(INCL_EXEC/EXCL_EXEC). + + After option processing, `gprof' finishes building the symspec list +by adding all the symspecs in `default_excluded_list' to the exclude +lists EXCL_TIME and EXCL_GRAPH, and if line-by-line profiling is +specified, EXCL_FLAT as well. These default excludes are not added to +EXCL_ANNO, EXCL_ARCS, and EXCL_EXEC. + + Next, the BFD library is called to open the object file, verify that +it is an object file, and read its symbol table (`core.c:core_init'), +using `bfd_canonicalize_symtab' after mallocing an appropriately sized +array of symbols. At this point, function mappings are read (if the +`--file-ordering' option has been specified), and the core text space +is read into memory (if the `-c' option was given). + + `gprof''s own symbol table, an array of Sym structures, is now built. +This is done in one of two ways, by one of two routines, depending on +whether line-by-line profiling (`-l' option) has been enabled. For +normal profiling, the BFD canonical symbol table is scanned. For +line-by-line profiling, every text space address is examined, and a new +symbol table entry gets created every time the line number changes. In +either case, two passes are made through the symbol table--one to count +the size of the symbol table required, and the other to actually read +the symbols. In between the two passes, a single array of type `Sym' +is created of the appropriate length. Finally, +`symtab.c:symtab_finalize' is called to sort the symbol table and +remove duplicate entries (entries with the same memory address). + + The symbol table must be a contiguous array for two reasons. First, +the `qsort' library function (which sorts an array) will be used to +sort the symbol table. Also, the symbol lookup routine +(`symtab.c:sym_lookup'), which finds symbols based on memory address, +uses a binary search algorithm which requires the symbol table to be a +sorted array. Function symbols are indicated with an `is_func' flag. +Line number symbols have no special flags set. Additionally, a symbol +can have an `is_static' flag to indicate that it is a local symbol. + + With the symbol table read, the symspecs can now be translated into +Syms (`sym_ids.c:sym_id_parse'). Remember that a single symspec can +match multiple symbols. An array of symbol tables (`syms') is created, +each entry of which is a symbol table of Syms to be included or +excluded from a particular listing. The master symbol table and the +symspecs are examined by nested loops, and every symbol that matches a +symspec is inserted into the appropriate syms table. This is done +twice, once to count the size of each required symbol table, and again +to build the tables, which have been malloced between passes. From now +on, to determine whether a symbol is on an include or exclude symspec +list, `gprof' simply uses its standard symbol lookup routine on the +appropriate table in the `syms' array. + + Now the profile data file(s) themselves are read +(`gmon_io.c:gmon_out_read'), first by checking for a new-style +`gmon.out' header, then assuming this is an old-style BSD `gmon.out' if +the magic number test failed. + + New-style histogram records are read by `hist.c:hist_read_rec'. For +the first histogram record, allocate a memory array to hold all the +bins, and read them in. When multiple profile data files (or files +with multiple histogram records) are read, the memory ranges of each +pair of histogram records must be either equal, or non-overlapping. +For each pair of histogram records, the resolution (memory region size +divided by the number of bins) must be the same. The time unit must be +the same for all histogram records. If the above containts are met, all +histograms for the same memory range are merged. + + As each call graph record is read (`call_graph.c:cg_read_rec'), the +parent and child addresses are matched to symbol table entries, and a +call graph arc is created by `cg_arcs.c:arc_add', unless the arc fails +a symspec check against INCL_ARCS/EXCL_ARCS. As each arc is added, a +linked list is maintained of the parent's child arcs, and of the child's +parent arcs. Both the child's call count and the arc's call count are +incremented by the record's call count. + + Basic-block records are read (`basic_blocks.c:bb_read_rec'), but +only if line-by-line profiling has been selected. Each basic-block +address is matched to a corresponding line symbol in the symbol table, +and an entry made in the symbol's bb_addr and bb_calls arrays. Again, +if multiple basic-block records are present for the same address, the +call counts are cumulative. + + A gmon.sum file is dumped, if requested (`gmon_io.c:gmon_out_write'). + + If histograms were present in the data files, assign them to symbols +(`hist.c:hist_assign_samples') by iterating over all the sample bins +and assigning them to symbols. Since the symbol table is sorted in +order of ascending memory addresses, we can simple follow along in the +symbol table as we make our pass over the sample bins. This step +includes a symspec check against INCL_FLAT/EXCL_FLAT. Depending on the +histogram scale factor, a sample bin may span multiple symbols, in +which case a fraction of the sample count is allocated to each symbol, +proportional to the degree of overlap. This effect is rare for normal +profiling, but overlaps are more common during line-by-line profiling, +and can cause each of two adjacent lines to be credited with half a +hit, for example. + + If call graph data is present, `cg_arcs.c:cg_assemble' is called. +First, if `-c' was specified, a machine-dependent routine (`find_call') +scans through each symbol's machine code, looking for subroutine call +instructions, and adding them to the call graph with a zero call count. +A topological sort is performed by depth-first numbering all the +symbols (`cg_dfn.c:cg_dfn'), so that children are always numbered less +than their parents, then making a array of pointers into the symbol +table and sorting it into numerical order, which is reverse topological +order (children appear before parents). Cycles are also detected at +this point, all members of which are assigned the same topological +number. Two passes are now made through this sorted array of symbol +pointers. The first pass, from end to beginning (parents to children), +computes the fraction of child time to propagate to each parent and a +print flag. The print flag reflects symspec handling of +INCL_GRAPH/EXCL_GRAPH, with a parent's include or exclude (print or no +print) property being propagated to its children, unless they +themselves explicitly appear in INCL_GRAPH or EXCL_GRAPH. A second +pass, from beginning to end (children to parents) actually propagates +the timings along the call graph, subject to a check against +INCL_TIME/EXCL_TIME. With the print flag, fractions, and timings now +stored in the symbol structures, the topological sort array is now +discarded, and a new array of pointers is assembled, this time sorted +by propagated time. + + Finally, print the various outputs the user requested, which is now +fairly straightforward. The call graph (`cg_print.c:cg_print') and +flat profile (`hist.c:hist_print') are regurgitations of values already +computed. The annotated source listing +(`basic_blocks.c:print_annotated_source') uses basic-block information, +if present, to label each line of code with call counts, otherwise only +the function call counts are presented. + + The function ordering code is marginally well documented in the +source code itself (`cg_print.c'). Basically, the functions with the +most use and the most parents are placed first, followed by other +functions with the most use, followed by lower use functions, followed +by unused functions at the end. + + +File: gprof.info, Node: Debugging, Prev: Internals, Up: Details + +9.4 Debugging `gprof' +===================== + +If `gprof' was compiled with debugging enabled, the `-d' option +triggers debugging output (to stdout) which can be helpful in +understanding its operation. The debugging number specified is +interpreted as a sum of the following options: + +2 - Topological sort + Monitor depth-first numbering of symbols during call graph analysis + +4 - Cycles + Shows symbols as they are identified as cycle heads + +16 - Tallying + As the call graph arcs are read, show each arc and how the total + calls to each function are tallied + +32 - Call graph arc sorting + Details sorting individual parents/children within each call graph + entry + +64 - Reading histogram and call graph records + Shows address ranges of histograms as they are read, and each call + graph arc + +128 - Symbol table + Reading, classifying, and sorting the symbol table from the object + file. For line-by-line profiling (`-l' option), also shows line + numbers being assigned to memory addresses. + +256 - Static call graph + Trace operation of `-c' option + +512 - Symbol table and arc table lookups + Detail operation of lookup routines + +1024 - Call graph propagation + Shows how function times are propagated along the call graph + +2048 - Basic-blocks + Shows basic-block records as they are read from profile data (only + meaningful with `-l' option) + +4096 - Symspecs + Shows symspec-to-symbol pattern matching operation + +8192 - Annotate source + Tracks operation of `-A' option + + +File: gprof.info, Node: GNU Free Documentation License, Prev: Details, Up: Top + +Appendix A GNU Free Documentation License +***************************************** + + Version 1.3, 3 November 2008 + + Copyright (C) 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc. + `http://fsf.org/' + + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + 0. 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Add an appropriate copyright notice for your modifications + adjacent to the other copyright notices. + + F. Include, immediately after the copyright notices, a license + notice giving the public permission to use the Modified + Version under the terms of this License, in the form shown in + the Addendum below. + + G. Preserve in that license notice the full lists of Invariant + Sections and required Cover Texts given in the Document's + license notice. + + H. Include an unaltered copy of this License. + + I. Preserve the section Entitled "History", Preserve its Title, + and add to it an item stating at least the title, year, new + authors, and publisher of the Modified Version as given on + the Title Page. If there is no section Entitled "History" in + the Document, create one stating the title, year, authors, + and publisher of the Document as given on its Title Page, + then add an item describing the Modified Version as stated in + the previous sentence. + + J. Preserve the network location, if any, given in the Document + for public access to a Transparent copy of the Document, and + likewise the network locations given in the Document for + previous versions it was based on. These may be placed in + the "History" section. You may omit a network location for a + work that was published at least four years before the + Document itself, or if the original publisher of the version + it refers to gives permission. + + K. For any section Entitled "Acknowledgements" or "Dedications", + Preserve the Title of the section, and preserve in the + section all the substance and tone of each of the contributor + acknowledgements and/or dedications given therein. + + L. Preserve all the Invariant Sections of the Document, + unaltered in their text and in their titles. Section numbers + or the equivalent are not considered part of the section + titles. + + M. Delete any section Entitled "Endorsements". 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AGGREGATION WITH INDEPENDENT WORKS + + A compilation of the Document or its derivatives with other + separate and independent documents or works, in or on a volume of + a storage or distribution medium, is called an "aggregate" if the + copyright resulting from the compilation is not used to limit the + legal rights of the compilation's users beyond what the individual + works permit. When the Document is included in an aggregate, this + License does not apply to the other works in the aggregate which + are not themselves derivative works of the Document. + + If the Cover Text requirement of section 3 is applicable to these + copies of the Document, then if the Document is less than one half + of the entire aggregate, the Document's Cover Texts may be placed + on covers that bracket the Document within the aggregate, or the + electronic equivalent of covers if the Document is in electronic + form. Otherwise they must appear on printed covers that bracket + the whole aggregate. + + 8. 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A copy of the license is included in the section entitled ``GNU + Free Documentation License''. + + If you have Invariant Sections, Front-Cover Texts and Back-Cover +Texts, replace the "with...Texts." line with this: + + with the Invariant Sections being LIST THEIR TITLES, with + the Front-Cover Texts being LIST, and with the Back-Cover Texts + being LIST. + + If you have Invariant Sections without Cover Texts, or some other +combination of the three, merge those two alternatives to suit the +situation. + + If your document contains nontrivial examples of program code, we +recommend releasing these examples in parallel under your choice of +free software license, such as the GNU General Public License, to +permit their use in free software. + + + +Tag Table: +Node: Top731 +Node: Introduction2054 +Node: Compiling4546 +Node: Executing8602 +Node: Invoking11390 +Node: Output Options12805 +Node: Analysis Options19894 +Node: Miscellaneous Options23592 +Node: Deprecated Options24847 +Node: Symspecs26926 +Node: Output28752 +Node: Flat Profile29792 +Node: Call Graph34745 +Node: Primary37977 +Node: Callers40565 +Node: Subroutines42682 +Node: Cycles44523 +Node: Line-by-line51300 +Node: Annotated Source55373 +Node: Inaccuracy58372 +Node: Sampling Error58630 +Node: Assumptions61200 +Node: How do I?62670 +Node: Incompatibilities64224 +Node: Details65718 +Node: Implementation66111 +Node: File Format72008 +Node: Internals76298 +Node: Debugging84793 +Node: GNU Free Documentation License86394 + +End Tag Table diff --git a/uclibc-crosstools-gcc-4.4.2-1/usr/share/info/ld.info b/uclibc-crosstools-gcc-4.4.2-1/usr/share/info/ld.info new file mode 100644 index 0000000..6022958 --- /dev/null +++ b/uclibc-crosstools-gcc-4.4.2-1/usr/share/info/ld.info @@ -0,0 +1,7611 @@ +This is ld.info, produced by makeinfo version 4.8 from ld.texinfo. + +START-INFO-DIR-ENTRY +* Ld: (ld). The GNU linker. +END-INFO-DIR-ENTRY + + This file documents the GNU linker LD (GNU Binutils) version 2.20. + + Copyright (C) 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000, 2001, +2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 Free Software +Foundation, Inc. + + Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation; with no +Invariant Sections, with no Front-Cover Texts, and with no Back-Cover +Texts. A copy of the license is included in the section entitled "GNU +Free Documentation License". + + +File: ld.info, Node: Top, Next: Overview, Up: (dir) + +LD +** + +This file documents the GNU linker ld (GNU Binutils) version 2.20. + + This document is distributed under the terms of the GNU Free +Documentation License version 1.3. A copy of the license is included +in the section entitled "GNU Free Documentation License". + +* Menu: + +* Overview:: Overview +* Invocation:: Invocation +* Scripts:: Linker Scripts + +* Machine Dependent:: Machine Dependent Features + +* BFD:: BFD + +* Reporting Bugs:: Reporting Bugs +* MRI:: MRI Compatible Script Files +* GNU Free Documentation License:: GNU Free Documentation License +* LD Index:: LD Index + + +File: ld.info, Node: Overview, Next: Invocation, Prev: Top, Up: Top + +1 Overview +********** + +`ld' combines a number of object and archive files, relocates their +data and ties up symbol references. Usually the last step in compiling +a program is to run `ld'. + + `ld' accepts Linker Command Language files written in a superset of +AT&T's Link Editor Command Language syntax, to provide explicit and +total control over the linking process. + + This version of `ld' uses the general purpose BFD libraries to +operate on object files. This allows `ld' to read, combine, and write +object files in many different formats--for example, COFF or `a.out'. +Different formats may be linked together to produce any available kind +of object file. *Note BFD::, for more information. + + Aside from its flexibility, the GNU linker is more helpful than other +linkers in providing diagnostic information. Many linkers abandon +execution immediately upon encountering an error; whenever possible, +`ld' continues executing, allowing you to identify other errors (or, in +some cases, to get an output file in spite of the error). + + +File: ld.info, Node: Invocation, Next: Scripts, Prev: Overview, Up: Top + +2 Invocation +************ + +The GNU linker `ld' is meant to cover a broad range of situations, and +to be as compatible as possible with other linkers. As a result, you +have many choices to control its behavior. + +* Menu: + +* Options:: Command Line Options +* Environment:: Environment Variables + + +File: ld.info, Node: Options, Next: Environment, Up: Invocation + +2.1 Command Line Options +======================== + + The linker supports a plethora of command-line options, but in actual +practice few of them are used in any particular context. For instance, +a frequent use of `ld' is to link standard Unix object files on a +standard, supported Unix system. On such a system, to link a file +`hello.o': + + ld -o OUTPUT /lib/crt0.o hello.o -lc + + This tells `ld' to produce a file called OUTPUT as the result of +linking the file `/lib/crt0.o' with `hello.o' and the library `libc.a', +which will come from the standard search directories. (See the +discussion of the `-l' option below.) + + Some of the command-line options to `ld' may be specified at any +point in the command line. However, options which refer to files, such +as `-l' or `-T', cause the file to be read at the point at which the +option appears in the command line, relative to the object files and +other file options. Repeating non-file options with a different +argument will either have no further effect, or override prior +occurrences (those further to the left on the command line) of that +option. Options which may be meaningfully specified more than once are +noted in the descriptions below. + + Non-option arguments are object files or archives which are to be +linked together. They may follow, precede, or be mixed in with +command-line options, except that an object file argument may not be +placed between an option and its argument. + + Usually the linker is invoked with at least one object file, but you +can specify other forms of binary input files using `-l', `-R', and the +script command language. If _no_ binary input files at all are +specified, the linker does not produce any output, and issues the +message `No input files'. + + If the linker cannot recognize the format of an object file, it will +assume that it is a linker script. A script specified in this way +augments the main linker script used for the link (either the default +linker script or the one specified by using `-T'). This feature +permits the linker to link against a file which appears to be an object +or an archive, but actually merely defines some symbol values, or uses +`INPUT' or `GROUP' to load other objects. Specifying a script in this +way merely augments the main linker script, with the extra commands +placed after the main script; use the `-T' option to replace the +default linker script entirely, but note the effect of the `INSERT' +command. *Note Scripts::. + + For options whose names are a single letter, option arguments must +either follow the option letter without intervening whitespace, or be +given as separate arguments immediately following the option that +requires them. + + For options whose names are multiple letters, either one dash or two +can precede the option name; for example, `-trace-symbol' and +`--trace-symbol' are equivalent. Note--there is one exception to this +rule. Multiple letter options that start with a lower case 'o' can +only be preceded by two dashes. This is to reduce confusion with the +`-o' option. So for example `-omagic' sets the output file name to +`magic' whereas `--omagic' sets the NMAGIC flag on the output. + + Arguments to multiple-letter options must either be separated from +the option name by an equals sign, or be given as separate arguments +immediately following the option that requires them. For example, +`--trace-symbol foo' and `--trace-symbol=foo' are equivalent. Unique +abbreviations of the names of multiple-letter options are accepted. + + Note--if the linker is being invoked indirectly, via a compiler +driver (e.g. `gcc') then all the linker command line options should be +prefixed by `-Wl,' (or whatever is appropriate for the particular +compiler driver) like this: + + gcc -Wl,--start-group foo.o bar.o -Wl,--end-group + + This is important, because otherwise the compiler driver program may +silently drop the linker options, resulting in a bad link. Confusion +may also arise when passing options that require values through a +driver, as the use of a space between option and argument acts as a +separator, and causes the driver to pass only the option to the linker +and the argument to the compiler. In this case, it is simplest to use +the joined forms of both single- and multiple-letter options, such as: + + gcc foo.o bar.o -Wl,-eENTRY -Wl,-Map=a.map + + Here is a table of the generic command line switches accepted by the +GNU linker: + +`@FILE' + Read command-line options from FILE. The options read are + inserted in place of the original @FILE option. If FILE does not + exist, or cannot be read, then the option will be treated + literally, and not removed. + + Options in FILE are separated by whitespace. A whitespace + character may be included in an option by surrounding the entire + option in either single or double quotes. Any character + (including a backslash) may be included by prefixing the character + to be included with a backslash. The FILE may itself contain + additional @FILE options; any such options will be processed + recursively. + +`-a KEYWORD' + This option is supported for HP/UX compatibility. The KEYWORD + argument must be one of the strings `archive', `shared', or + `default'. `-aarchive' is functionally equivalent to `-Bstatic', + and the other two keywords are functionally equivalent to + `-Bdynamic'. This option may be used any number of times. + +`-A ARCHITECTURE' +`--architecture=ARCHITECTURE' + In the current release of `ld', this option is useful only for the + Intel 960 family of architectures. In that `ld' configuration, the + ARCHITECTURE argument identifies the particular architecture in + the 960 family, enabling some safeguards and modifying the + archive-library search path. *Note `ld' and the Intel 960 family: + i960, for details. + + Future releases of `ld' may support similar functionality for + other architecture families. + +`-b INPUT-FORMAT' +`--format=INPUT-FORMAT' + `ld' may be configured to support more than one kind of object + file. If your `ld' is configured this way, you can use the `-b' + option to specify the binary format for input object files that + follow this option on the command line. Even when `ld' is + configured to support alternative object formats, you don't + usually need to specify this, as `ld' should be configured to + expect as a default input format the most usual format on each + machine. INPUT-FORMAT is a text string, the name of a particular + format supported by the BFD libraries. (You can list the + available binary formats with `objdump -i'.) *Note BFD::. + + You may want to use this option if you are linking files with an + unusual binary format. You can also use `-b' to switch formats + explicitly (when linking object files of different formats), by + including `-b INPUT-FORMAT' before each group of object files in a + particular format. + + The default format is taken from the environment variable + `GNUTARGET'. *Note Environment::. You can also define the input + format from a script, using the command `TARGET'; see *Note Format + Commands::. + +`-c MRI-COMMANDFILE' +`--mri-script=MRI-COMMANDFILE' + For compatibility with linkers produced by MRI, `ld' accepts script + files written in an alternate, restricted command language, + described in *Note MRI Compatible Script Files: MRI. Introduce + MRI script files with the option `-c'; use the `-T' option to run + linker scripts written in the general-purpose `ld' scripting + language. If MRI-CMDFILE does not exist, `ld' looks for it in the + directories specified by any `-L' options. + +`-d' +`-dc' +`-dp' + These three options are equivalent; multiple forms are supported + for compatibility with other linkers. They assign space to common + symbols even if a relocatable output file is specified (with + `-r'). The script command `FORCE_COMMON_ALLOCATION' has the same + effect. *Note Miscellaneous Commands::. + +`-e ENTRY' +`--entry=ENTRY' + Use ENTRY as the explicit symbol for beginning execution of your + program, rather than the default entry point. If there is no + symbol named ENTRY, the linker will try to parse ENTRY as a number, + and use that as the entry address (the number will be interpreted + in base 10; you may use a leading `0x' for base 16, or a leading + `0' for base 8). *Note Entry Point::, for a discussion of defaults + and other ways of specifying the entry point. + +`--exclude-libs LIB,LIB,...' + Specifies a list of archive libraries from which symbols should + not be automatically exported. The library names may be delimited + by commas or colons. Specifying `--exclude-libs ALL' excludes + symbols in all archive libraries from automatic export. This + option is available only for the i386 PE targeted port of the + linker and for ELF targeted ports. For i386 PE, symbols + explicitly listed in a .def file are still exported, regardless of + this option. For ELF targeted ports, symbols affected by this + option will be treated as hidden. + +`--exclude-modules-for-implib MODULE,MODULE,...' + Specifies a list of object files or archive members, from which + symbols should not be automatically exported, but which should be + copied wholesale into the import library being generated during + the link. The module names may be delimited by commas or colons, + and must match exactly the filenames used by `ld' to open the + files; for archive members, this is simply the member name, but + for object files the name listed must include and match precisely + any path used to specify the input file on the linker's + command-line. This option is available only for the i386 PE + targeted port of the linker. Symbols explicitly listed in a .def + file are still exported, regardless of this option. + +`-E' +`--export-dynamic' +`--no-export-dynamic' + When creating a dynamically linked executable, using the `-E' + option or the `--export-dynamic' option causes the linker to add + all symbols to the dynamic symbol table. The dynamic symbol table + is the set of symbols which are visible from dynamic objects at + run time. + + If you do not use either of these options (or use the + `--no-export-dynamic' option to restore the default behavior), the + dynamic symbol table will normally contain only those symbols + which are referenced by some dynamic object mentioned in the link. + + If you use `dlopen' to load a dynamic object which needs to refer + back to the symbols defined by the program, rather than some other + dynamic object, then you will probably need to use this option when + linking the program itself. + + You can also use the dynamic list to control what symbols should + be added to the dynamic symbol table if the output format supports + it. See the description of `--dynamic-list'. + + Note that this option is specific to ELF targeted ports. PE + targets support a similar function to export all symbols from a + DLL or EXE; see the description of `--export-all-symbols' below. + +`-EB' + Link big-endian objects. This affects the default output format. + +`-EL' + Link little-endian objects. This affects the default output + format. + +`-f NAME' +`--auxiliary=NAME' + When creating an ELF shared object, set the internal DT_AUXILIARY + field to the specified name. This tells the dynamic linker that + the symbol table of the shared object should be used as an + auxiliary filter on the symbol table of the shared object NAME. + + If you later link a program against this filter object, then, when + you run the program, the dynamic linker will see the DT_AUXILIARY + field. If the dynamic linker resolves any symbols from the filter + object, it will first check whether there is a definition in the + shared object NAME. If there is one, it will be used instead of + the definition in the filter object. The shared object NAME need + not exist. Thus the shared object NAME may be used to provide an + alternative implementation of certain functions, perhaps for + debugging or for machine specific performance. + + This option may be specified more than once. The DT_AUXILIARY + entries will be created in the order in which they appear on the + command line. + +`-F NAME' +`--filter=NAME' + When creating an ELF shared object, set the internal DT_FILTER + field to the specified name. This tells the dynamic linker that + the symbol table of the shared object which is being created + should be used as a filter on the symbol table of the shared + object NAME. + + If you later link a program against this filter object, then, when + you run the program, the dynamic linker will see the DT_FILTER + field. The dynamic linker will resolve symbols according to the + symbol table of the filter object as usual, but it will actually + link to the definitions found in the shared object NAME. Thus the + filter object can be used to select a subset of the symbols + provided by the object NAME. + + Some older linkers used the `-F' option throughout a compilation + toolchain for specifying object-file format for both input and + output object files. The GNU linker uses other mechanisms for + this purpose: the `-b', `--format', `--oformat' options, the + `TARGET' command in linker scripts, and the `GNUTARGET' + environment variable. The GNU linker will ignore the `-F' option + when not creating an ELF shared object. + +`-fini=NAME' + When creating an ELF executable or shared object, call NAME when + the executable or shared object is unloaded, by setting DT_FINI to + the address of the function. By default, the linker uses `_fini' + as the function to call. + +`-g' + Ignored. Provided for compatibility with other tools. + +`-G VALUE' +`--gpsize=VALUE' + Set the maximum size of objects to be optimized using the GP + register to SIZE. This is only meaningful for object file formats + such as MIPS ECOFF which supports putting large and small objects + into different sections. This is ignored for other object file + formats. + +`-h NAME' +`-soname=NAME' + When creating an ELF shared object, set the internal DT_SONAME + field to the specified name. When an executable is linked with a + shared object which has a DT_SONAME field, then when the + executable is run the dynamic linker will attempt to load the + shared object specified by the DT_SONAME field rather than the + using the file name given to the linker. + +`-i' + Perform an incremental link (same as option `-r'). + +`-init=NAME' + When creating an ELF executable or shared object, call NAME when + the executable or shared object is loaded, by setting DT_INIT to + the address of the function. By default, the linker uses `_init' + as the function to call. + +`-l NAMESPEC' +`--library=NAMESPEC' + Add the archive or object file specified by NAMESPEC to the list + of files to link. This option may be used any number of times. + If NAMESPEC is of the form `:FILENAME', `ld' will search the + library path for a file called FILENAME, otherwise it will search + the library path for a file called `libNAMESPEC.a'. + + On systems which support shared libraries, `ld' may also search for + files other than `libNAMESPEC.a'. Specifically, on ELF and SunOS + systems, `ld' will search a directory for a library called + `libNAMESPEC.so' before searching for one called `libNAMESPEC.a'. + (By convention, a `.so' extension indicates a shared library.) + Note that this behavior does not apply to `:FILENAME', which + always specifies a file called FILENAME. + + The linker will search an archive only once, at the location where + it is specified on the command line. If the archive defines a + symbol which was undefined in some object which appeared before + the archive on the command line, the linker will include the + appropriate file(s) from the archive. However, an undefined + symbol in an object appearing later on the command line will not + cause the linker to search the archive again. + + See the `-(' option for a way to force the linker to search + archives multiple times. + + You may list the same archive multiple times on the command line. + + This type of archive searching is standard for Unix linkers. + However, if you are using `ld' on AIX, note that it is different + from the behaviour of the AIX linker. + +`-L SEARCHDIR' +`--library-path=SEARCHDIR' + Add path SEARCHDIR to the list of paths that `ld' will search for + archive libraries and `ld' control scripts. You may use this + option any number of times. The directories are searched in the + order in which they are specified on the command line. + Directories specified on the command line are searched before the + default directories. All `-L' options apply to all `-l' options, + regardless of the order in which the options appear. `-L' options + do not affect how `ld' searches for a linker script unless `-T' + option is specified. + + If SEARCHDIR begins with `=', then the `=' will be replaced by the + "sysroot prefix", a path specified when the linker is configured. + + The default set of paths searched (without being specified with + `-L') depends on which emulation mode `ld' is using, and in some + cases also on how it was configured. *Note Environment::. + + The paths can also be specified in a link script with the + `SEARCH_DIR' command. Directories specified this way are searched + at the point in which the linker script appears in the command + line. + +`-m EMULATION' + Emulate the EMULATION linker. You can list the available + emulations with the `--verbose' or `-V' options. + + If the `-m' option is not used, the emulation is taken from the + `LDEMULATION' environment variable, if that is defined. + + Otherwise, the default emulation depends upon how the linker was + configured. + +`-M' +`--print-map' + Print a link map to the standard output. A link map provides + information about the link, including the following: + + * Where object files are mapped into memory. + + * How common symbols are allocated. + + * All archive members included in the link, with a mention of + the symbol which caused the archive member to be brought in. + + * The values assigned to symbols. + + Note - symbols whose values are computed by an expression + which involves a reference to a previous value of the same + symbol may not have correct result displayed in the link map. + This is because the linker discards intermediate results and + only retains the final value of an expression. Under such + circumstances the linker will display the final value + enclosed by square brackets. Thus for example a linker + script containing: + + foo = 1 + foo = foo * 4 + foo = foo + 8 + + will produce the following output in the link map if the `-M' + option is used: + + 0x00000001 foo = 0x1 + [0x0000000c] foo = (foo * 0x4) + [0x0000000c] foo = (foo + 0x8) + + See *Note Expressions:: for more information about + expressions in linker scripts. + +`-n' +`--nmagic' + Turn off page alignment of sections, and mark the output as + `NMAGIC' if possible. + +`-N' +`--omagic' + Set the text and data sections to be readable and writable. Also, + do not page-align the data segment, and disable linking against + shared libraries. If the output format supports Unix style magic + numbers, mark the output as `OMAGIC'. Note: Although a writable + text section is allowed for PE-COFF targets, it does not conform + to the format specification published by Microsoft. + +`--no-omagic' + This option negates most of the effects of the `-N' option. It + sets the text section to be read-only, and forces the data segment + to be page-aligned. Note - this option does not enable linking + against shared libraries. Use `-Bdynamic' for this. + +`-o OUTPUT' +`--output=OUTPUT' + Use OUTPUT as the name for the program produced by `ld'; if this + option is not specified, the name `a.out' is used by default. The + script command `OUTPUT' can also specify the output file name. + +`-O LEVEL' + If LEVEL is a numeric values greater than zero `ld' optimizes the + output. This might take significantly longer and therefore + probably should only be enabled for the final binary. At the + moment this option only affects ELF shared library generation. + Future releases of the linker may make more use of this option. + Also currently there is no difference in the linker's behaviour + for different non-zero values of this option. Again this may + change with future releases. + +`-q' +`--emit-relocs' + Leave relocation sections and contents in fully linked executables. + Post link analysis and optimization tools may need this + information in order to perform correct modifications of + executables. This results in larger executables. + + This option is currently only supported on ELF platforms. + +`--force-dynamic' + Force the output file to have dynamic sections. This option is + specific to VxWorks targets. + +`-r' +`--relocatable' + Generate relocatable output--i.e., generate an output file that + can in turn serve as input to `ld'. This is often called "partial + linking". As a side effect, in environments that support standard + Unix magic numbers, this option also sets the output file's magic + number to `OMAGIC'. If this option is not specified, an absolute + file is produced. When linking C++ programs, this option _will + not_ resolve references to constructors; to do that, use `-Ur'. + + When an input file does not have the same format as the output + file, partial linking is only supported if that input file does + not contain any relocations. Different output formats can have + further restrictions; for example some `a.out'-based formats do + not support partial linking with input files in other formats at + all. + + This option does the same thing as `-i'. + +`-R FILENAME' +`--just-symbols=FILENAME' + Read symbol names and their addresses from FILENAME, but do not + relocate it or include it in the output. This allows your output + file to refer symbolically to absolute locations of memory defined + in other programs. You may use this option more than once. + + For compatibility with other ELF linkers, if the `-R' option is + followed by a directory name, rather than a file name, it is + treated as the `-rpath' option. + +`-s' +`--strip-all' + Omit all symbol information from the output file. + +`-S' +`--strip-debug' + Omit debugger symbol information (but not all symbols) from the + output file. + +`-t' +`--trace' + Print the names of the input files as `ld' processes them. + +`-T SCRIPTFILE' +`--script=SCRIPTFILE' + Use SCRIPTFILE as the linker script. This script replaces `ld''s + default linker script (rather than adding to it), so COMMANDFILE + must specify everything necessary to describe the output file. + *Note Scripts::. If SCRIPTFILE does not exist in the current + directory, `ld' looks for it in the directories specified by any + preceding `-L' options. Multiple `-T' options accumulate. + +`-dT SCRIPTFILE' +`--default-script=SCRIPTFILE' + Use SCRIPTFILE as the default linker script. *Note Scripts::. + + This option is similar to the `--script' option except that + processing of the script is delayed until after the rest of the + command line has been processed. This allows options placed after + the `--default-script' option on the command line to affect the + behaviour of the linker script, which can be important when the + linker command line cannot be directly controlled by the user. + (eg because the command line is being constructed by another tool, + such as `gcc'). + +`-u SYMBOL' +`--undefined=SYMBOL' + Force SYMBOL to be entered in the output file as an undefined + symbol. Doing this may, for example, trigger linking of additional + modules from standard libraries. `-u' may be repeated with + different option arguments to enter additional undefined symbols. + This option is equivalent to the `EXTERN' linker script command. + +`-Ur' + For anything other than C++ programs, this option is equivalent to + `-r': it generates relocatable output--i.e., an output file that + can in turn serve as input to `ld'. When linking C++ programs, + `-Ur' _does_ resolve references to constructors, unlike `-r'. It + does not work to use `-Ur' on files that were themselves linked + with `-Ur'; once the constructor table has been built, it cannot + be added to. Use `-Ur' only for the last partial link, and `-r' + for the others. + +`--unique[=SECTION]' + Creates a separate output section for every input section matching + SECTION, or if the optional wildcard SECTION argument is missing, + for every orphan input section. An orphan section is one not + specifically mentioned in a linker script. You may use this option + multiple times on the command line; It prevents the normal + merging of input sections with the same name, overriding output + section assignments in a linker script. + +`-v' +`--version' +`-V' + Display the version number for `ld'. The `-V' option also lists + the supported emulations. + +`-x' +`--discard-all' + Delete all local symbols. + +`-X' +`--discard-locals' + Delete all temporary local symbols. (These symbols start with + system-specific local label prefixes, typically `.L' for ELF + systems or `L' for traditional a.out systems.) + +`-y SYMBOL' +`--trace-symbol=SYMBOL' + Print the name of each linked file in which SYMBOL appears. This + option may be given any number of times. On many systems it is + necessary to prepend an underscore. + + This option is useful when you have an undefined symbol in your + link but don't know where the reference is coming from. + +`-Y PATH' + Add PATH to the default library search path. This option exists + for Solaris compatibility. + +`-z KEYWORD' + The recognized keywords are: + `combreloc' + Combines multiple reloc sections and sorts them to make + dynamic symbol lookup caching possible. + + `defs' + Disallows undefined symbols in object files. Undefined + symbols in shared libraries are still allowed. + + `execstack' + Marks the object as requiring executable stack. + + `initfirst' + This option is only meaningful when building a shared object. + It marks the object so that its runtime initialization will + occur before the runtime initialization of any other objects + brought into the process at the same time. Similarly the + runtime finalization of the object will occur after the + runtime finalization of any other objects. + + `interpose' + Marks the object that its symbol table interposes before all + symbols but the primary executable. + + `lazy' + When generating an executable or shared library, mark it to + tell the dynamic linker to defer function call resolution to + the point when the function is called (lazy binding), rather + than at load time. Lazy binding is the default. + + `loadfltr' + Marks the object that its filters be processed immediately at + runtime. + + `muldefs' + Allows multiple definitions. + + `nocombreloc' + Disables multiple reloc sections combining. + + `nocopyreloc' + Disables production of copy relocs. + + `nodefaultlib' + Marks the object that the search for dependencies of this + object will ignore any default library search paths. + + `nodelete' + Marks the object shouldn't be unloaded at runtime. + + `nodlopen' + Marks the object not available to `dlopen'. + + `nodump' + Marks the object can not be dumped by `dldump'. + + `noexecstack' + Marks the object as not requiring executable stack. + + `norelro' + Don't create an ELF `PT_GNU_RELRO' segment header in the + object. + + `now' + When generating an executable or shared library, mark it to + tell the dynamic linker to resolve all symbols when the + program is started, or when the shared library is linked to + using dlopen, instead of deferring function call resolution + to the point when the function is first called. + + `origin' + Marks the object may contain $ORIGIN. + + `relro' + Create an ELF `PT_GNU_RELRO' segment header in the object. + + `max-page-size=VALUE' + Set the emulation maximum page size to VALUE. + + `common-page-size=VALUE' + Set the emulation common page size to VALUE. + + + Other keywords are ignored for Solaris compatibility. + +`-( ARCHIVES -)' +`--start-group ARCHIVES --end-group' + The ARCHIVES should be a list of archive files. They may be + either explicit file names, or `-l' options. + + The specified archives are searched repeatedly until no new + undefined references are created. Normally, an archive is + searched only once in the order that it is specified on the + command line. If a symbol in that archive is needed to resolve an + undefined symbol referred to by an object in an archive that + appears later on the command line, the linker would not be able to + resolve that reference. By grouping the archives, they all be + searched repeatedly until all possible references are resolved. + + Using this option has a significant performance cost. It is best + to use it only when there are unavoidable circular references + between two or more archives. + +`--accept-unknown-input-arch' +`--no-accept-unknown-input-arch' + Tells the linker to accept input files whose architecture cannot be + recognised. The assumption is that the user knows what they are + doing and deliberately wants to link in these unknown input files. + This was the default behaviour of the linker, before release + 2.14. The default behaviour from release 2.14 onwards is to + reject such input files, and so the `--accept-unknown-input-arch' + option has been added to restore the old behaviour. + +`--as-needed' +`--no-as-needed' + This option affects ELF DT_NEEDED tags for dynamic libraries + mentioned on the command line after the `--as-needed' option. + Normally, the linker will add a DT_NEEDED tag for each dynamic + library mentioned on the command line, regardless of whether the + library is actually needed. `--as-needed' causes a DT_NEEDED tag + to only be emitted for a library that satisfies a symbol reference + from regular objects which is undefined at the point that the + library was linked, or, if the library is not found in the + DT_NEEDED lists of other libraries linked up to that point, a + reference from another dynamic library. `--no-as-needed' restores + the default behaviour. + +`--add-needed' +`--no-add-needed' + This option affects the treatment of dynamic libraries from ELF + DT_NEEDED tags in dynamic libraries mentioned on the command line + after the `--no-add-needed' option. Normally, the linker will add + a DT_NEEDED tag for each dynamic library from DT_NEEDED tags. + `--no-add-needed' causes DT_NEEDED tags will never be emitted for + those libraries from DT_NEEDED tags. `--add-needed' restores the + default behaviour. + +`-assert KEYWORD' + This option is ignored for SunOS compatibility. + +`-Bdynamic' +`-dy' +`-call_shared' + Link against dynamic libraries. This is only meaningful on + platforms for which shared libraries are supported. This option + is normally the default on such platforms. The different variants + of this option are for compatibility with various systems. You + may use this option multiple times on the command line: it affects + library searching for `-l' options which follow it. + +`-Bgroup' + Set the `DF_1_GROUP' flag in the `DT_FLAGS_1' entry in the dynamic + section. This causes the runtime linker to handle lookups in this + object and its dependencies to be performed only inside the group. + `--unresolved-symbols=report-all' is implied. This option is only + meaningful on ELF platforms which support shared libraries. + +`-Bstatic' +`-dn' +`-non_shared' +`-static' + Do not link against shared libraries. This is only meaningful on + platforms for which shared libraries are supported. The different + variants of this option are for compatibility with various + systems. You may use this option multiple times on the command + line: it affects library searching for `-l' options which follow + it. This option also implies `--unresolved-symbols=report-all'. + This option can be used with `-shared'. Doing so means that a + shared library is being created but that all of the library's + external references must be resolved by pulling in entries from + static libraries. + +`-Bsymbolic' + When creating a shared library, bind references to global symbols + to the definition within the shared library, if any. Normally, it + is possible for a program linked against a shared library to + override the definition within the shared library. This option is + only meaningful on ELF platforms which support shared libraries. + +`-Bsymbolic-functions' + When creating a shared library, bind references to global function + symbols to the definition within the shared library, if any. This + option is only meaningful on ELF platforms which support shared + libraries. + +`--dynamic-list=DYNAMIC-LIST-FILE' + Specify the name of a dynamic list file to the linker. This is + typically used when creating shared libraries to specify a list of + global symbols whose references shouldn't be bound to the + definition within the shared library, or creating dynamically + linked executables to specify a list of symbols which should be + added to the symbol table in the executable. This option is only + meaningful on ELF platforms which support shared libraries. + + The format of the dynamic list is the same as the version node + without scope and node name. See *Note VERSION:: for more + information. + +`--dynamic-list-data' + Include all global data symbols to the dynamic list. + +`--dynamic-list-cpp-new' + Provide the builtin dynamic list for C++ operator new and delete. + It is mainly useful for building shared libstdc++. + +`--dynamic-list-cpp-typeinfo' + Provide the builtin dynamic list for C++ runtime type + identification. + +`--check-sections' +`--no-check-sections' + Asks the linker _not_ to check section addresses after they have + been assigned to see if there are any overlaps. Normally the + linker will perform this check, and if it finds any overlaps it + will produce suitable error messages. The linker does know about, + and does make allowances for sections in overlays. The default + behaviour can be restored by using the command line switch + `--check-sections'. Section overlap is not usually checked for + relocatable links. You can force checking in that case by using + the `--check-sections' option. + +`--cref' + Output a cross reference table. If a linker map file is being + generated, the cross reference table is printed to the map file. + Otherwise, it is printed on the standard output. + + The format of the table is intentionally simple, so that it may be + easily processed by a script if necessary. The symbols are + printed out, sorted by name. For each symbol, a list of file + names is given. If the symbol is defined, the first file listed + is the location of the definition. The remaining files contain + references to the symbol. + +`--no-define-common' + This option inhibits the assignment of addresses to common symbols. + The script command `INHIBIT_COMMON_ALLOCATION' has the same effect. + *Note Miscellaneous Commands::. + + The `--no-define-common' option allows decoupling the decision to + assign addresses to Common symbols from the choice of the output + file type; otherwise a non-Relocatable output type forces + assigning addresses to Common symbols. Using `--no-define-common' + allows Common symbols that are referenced from a shared library to + be assigned addresses only in the main program. This eliminates + the unused duplicate space in the shared library, and also + prevents any possible confusion over resolving to the wrong + duplicate when there are many dynamic modules with specialized + search paths for runtime symbol resolution. + +`--defsym=SYMBOL=EXPRESSION' + Create a global symbol in the output file, containing the absolute + address given by EXPRESSION. You may use this option as many + times as necessary to define multiple symbols in the command line. + A limited form of arithmetic is supported for the EXPRESSION in + this context: you may give a hexadecimal constant or the name of + an existing symbol, or use `+' and `-' to add or subtract + hexadecimal constants or symbols. If you need more elaborate + expressions, consider using the linker command language from a + script (*note Assignment: Symbol Definitions: Assignments.). + _Note:_ there should be no white space between SYMBOL, the equals + sign ("<=>"), and EXPRESSION. + +`--demangle[=STYLE]' +`--no-demangle' + These options control whether to demangle symbol names in error + messages and other output. When the linker is told to demangle, + it tries to present symbol names in a readable fashion: it strips + leading underscores if they are used by the object file format, + and converts C++ mangled symbol names into user readable names. + Different compilers have different mangling styles. The optional + demangling style argument can be used to choose an appropriate + demangling style for your compiler. The linker will demangle by + default unless the environment variable `COLLECT_NO_DEMANGLE' is + set. These options may be used to override the default. + +`-IFILE' +`--dynamic-linker=FILE' + Set the name of the dynamic linker. This is only meaningful when + generating dynamically linked ELF executables. The default dynamic + linker is normally correct; don't use this unless you know what + you are doing. + +`--fatal-warnings' +`--no-fatal-warnings' + Treat all warnings as errors. The default behaviour can be + restored with the option `--no-fatal-warnings'. + +`--force-exe-suffix' + Make sure that an output file has a .exe suffix. + + If a successfully built fully linked output file does not have a + `.exe' or `.dll' suffix, this option forces the linker to copy the + output file to one of the same name with a `.exe' suffix. This + option is useful when using unmodified Unix makefiles on a + Microsoft Windows host, since some versions of Windows won't run + an image unless it ends in a `.exe' suffix. + +`--gc-sections' +`--no-gc-sections' + Enable garbage collection of unused input sections. It is ignored + on targets that do not support this option. The default behaviour + (of not performing this garbage collection) can be restored by + specifying `--no-gc-sections' on the command line. + + `--gc-sections' decides which input sections are used by examining + symbols and relocations. The section containing the entry symbol + and all sections containing symbols undefined on the command-line + will be kept, as will sections containing symbols referenced by + dynamic objects. Note that when building shared libraries, the + linker must assume that any visible symbol is referenced. Once + this initial set of sections has been determined, the linker + recursively marks as used any section referenced by their + relocations. See `--entry' and `--undefined'. + + This option can be set when doing a partial link (enabled with + option `-r'). In this case the root of symbols kept must be + explicitely specified either by an `--entry' or `--undefined' + option or by a `ENTRY' command in the linker script. + +`--print-gc-sections' +`--no-print-gc-sections' + List all sections removed by garbage collection. The listing is + printed on stderr. This option is only effective if garbage + collection has been enabled via the `--gc-sections') option. The + default behaviour (of not listing the sections that are removed) + can be restored by specifying `--no-print-gc-sections' on the + command line. + +`--help' + Print a summary of the command-line options on the standard output + and exit. + +`--target-help' + Print a summary of all target specific options on the standard + output and exit. + +`-Map=MAPFILE' + Print a link map to the file MAPFILE. See the description of the + `-M' option, above. + +`--no-keep-memory' + `ld' normally optimizes for speed over memory usage by caching the + symbol tables of input files in memory. This option tells `ld' to + instead optimize for memory usage, by rereading the symbol tables + as necessary. This may be required if `ld' runs out of memory + space while linking a large executable. + +`--no-undefined' +`-z defs' + Report unresolved symbol references from regular object files. + This is done even if the linker is creating a non-symbolic shared + library. The switch `--[no-]allow-shlib-undefined' controls the + behaviour for reporting unresolved references found in shared + libraries being linked in. + +`--allow-multiple-definition' +`-z muldefs' + Normally when a symbol is defined multiple times, the linker will + report a fatal error. These options allow multiple definitions and + the first definition will be used. + +`--allow-shlib-undefined' +`--no-allow-shlib-undefined' + Allows or disallows undefined symbols in shared libraries. This + switch is similar to `--no-undefined' except that it determines + the behaviour when the undefined symbols are in a shared library + rather than a regular object file. It does not affect how + undefined symbols in regular object files are handled. + + The default behaviour is to report errors for any undefined symbols + referenced in shared libraries if the linker is being used to + create an executable, but to allow them if the linker is being + used to create a shared library. + + The reasons for allowing undefined symbol references in shared + libraries specified at link time are that: + + * A shared library specified at link time may not be the same + as the one that is available at load time, so the symbol + might actually be resolvable at load time. + + * There are some operating systems, eg BeOS and HPPA, where + undefined symbols in shared libraries are normal. + + The BeOS kernel for example patches shared libraries at load + time to select whichever function is most appropriate for the + current architecture. This is used, for example, to + dynamically select an appropriate memset function. + +`--no-undefined-version' + Normally when a symbol has an undefined version, the linker will + ignore it. This option disallows symbols with undefined version + and a fatal error will be issued instead. + +`--default-symver' + Create and use a default symbol version (the soname) for + unversioned exported symbols. + +`--default-imported-symver' + Create and use a default symbol version (the soname) for + unversioned imported symbols. + +`--no-warn-mismatch' + Normally `ld' will give an error if you try to link together input + files that are mismatched for some reason, perhaps because they + have been compiled for different processors or for different + endiannesses. This option tells `ld' that it should silently + permit such possible errors. This option should only be used with + care, in cases when you have taken some special action that + ensures that the linker errors are inappropriate. + +`--no-warn-search-mismatch' + Normally `ld' will give a warning if it finds an incompatible + library during a library search. This option silences the warning. + +`--no-whole-archive' + Turn off the effect of the `--whole-archive' option for subsequent + archive files. + +`--noinhibit-exec' + Retain the executable output file whenever it is still usable. + Normally, the linker will not produce an output file if it + encounters errors during the link process; it exits without + writing an output file when it issues any error whatsoever. + +`-nostdlib' + Only search library directories explicitly specified on the + command line. Library directories specified in linker scripts + (including linker scripts specified on the command line) are + ignored. + +`--oformat=OUTPUT-FORMAT' + `ld' may be configured to support more than one kind of object + file. If your `ld' is configured this way, you can use the + `--oformat' option to specify the binary format for the output + object file. Even when `ld' is configured to support alternative + object formats, you don't usually need to specify this, as `ld' + should be configured to produce as a default output format the most + usual format on each machine. OUTPUT-FORMAT is a text string, the + name of a particular format supported by the BFD libraries. (You + can list the available binary formats with `objdump -i'.) The + script command `OUTPUT_FORMAT' can also specify the output format, + but this option overrides it. *Note BFD::. + +`-pie' +`--pic-executable' + Create a position independent executable. This is currently only + supported on ELF platforms. Position independent executables are + similar to shared libraries in that they are relocated by the + dynamic linker to the virtual address the OS chooses for them + (which can vary between invocations). Like normal dynamically + linked executables they can be executed and symbols defined in the + executable cannot be overridden by shared libraries. + +`-qmagic' + This option is ignored for Linux compatibility. + +`-Qy' + This option is ignored for SVR4 compatibility. + +`--relax' + An option with machine dependent effects. This option is only + supported on a few targets. *Note `ld' and the H8/300: H8/300. + *Note `ld' and the Intel 960 family: i960. *Note `ld' and Xtensa + Processors: Xtensa. *Note `ld' and the 68HC11 and 68HC12: + M68HC11/68HC12. *Note `ld' and PowerPC 32-bit ELF Support: + PowerPC ELF32. + + On some platforms, the `--relax' option performs global + optimizations that become possible when the linker resolves + addressing in the program, such as relaxing address modes and + synthesizing new instructions in the output object file. + + On some platforms these link time global optimizations may make + symbolic debugging of the resulting executable impossible. This + is known to be the case for the Matsushita MN10200 and MN10300 + family of processors. + + On platforms where this is not supported, `--relax' is accepted, + but ignored. + +`--retain-symbols-file=FILENAME' + Retain _only_ the symbols listed in the file FILENAME, discarding + all others. FILENAME is simply a flat file, with one symbol name + per line. This option is especially useful in environments (such + as VxWorks) where a large global symbol table is accumulated + gradually, to conserve run-time memory. + + `--retain-symbols-file' does _not_ discard undefined symbols, or + symbols needed for relocations. + + You may only specify `--retain-symbols-file' once in the command + line. It overrides `-s' and `-S'. + +`-rpath=DIR' + Add a directory to the runtime library search path. This is used + when linking an ELF executable with shared objects. All `-rpath' + arguments are concatenated and passed to the runtime linker, which + uses them to locate shared objects at runtime. The `-rpath' + option is also used when locating shared objects which are needed + by shared objects explicitly included in the link; see the + description of the `-rpath-link' option. If `-rpath' is not used + when linking an ELF executable, the contents of the environment + variable `LD_RUN_PATH' will be used if it is defined. + + The `-rpath' option may also be used on SunOS. By default, on + SunOS, the linker will form a runtime search patch out of all the + `-L' options it is given. If a `-rpath' option is used, the + runtime search path will be formed exclusively using the `-rpath' + options, ignoring the `-L' options. This can be useful when using + gcc, which adds many `-L' options which may be on NFS mounted file + systems. + + For compatibility with other ELF linkers, if the `-R' option is + followed by a directory name, rather than a file name, it is + treated as the `-rpath' option. + +`-rpath-link=DIR' + When using ELF or SunOS, one shared library may require another. + This happens when an `ld -shared' link includes a shared library + as one of the input files. + + When the linker encounters such a dependency when doing a + non-shared, non-relocatable link, it will automatically try to + locate the required shared library and include it in the link, if + it is not included explicitly. In such a case, the `-rpath-link' + option specifies the first set of directories to search. The + `-rpath-link' option may specify a sequence of directory names + either by specifying a list of names separated by colons, or by + appearing multiple times. + + This option should be used with caution as it overrides the search + path that may have been hard compiled into a shared library. In + such a case it is possible to use unintentionally a different + search path than the runtime linker would do. + + The linker uses the following search paths to locate required + shared libraries: + 1. Any directories specified by `-rpath-link' options. + + 2. Any directories specified by `-rpath' options. The difference + between `-rpath' and `-rpath-link' is that directories + specified by `-rpath' options are included in the executable + and used at runtime, whereas the `-rpath-link' option is only + effective at link time. Searching `-rpath' in this way is + only supported by native linkers and cross linkers which have + been configured with the `--with-sysroot' option. + + 3. On an ELF system, for native linkers, if the `-rpath' and + `-rpath-link' options were not used, search the contents of + the environment variable `LD_RUN_PATH'. + + 4. On SunOS, if the `-rpath' option was not used, search any + directories specified using `-L' options. + + 5. For a native linker, the search the contents of the + environment variable `LD_LIBRARY_PATH'. + + 6. For a native ELF linker, the directories in `DT_RUNPATH' or + `DT_RPATH' of a shared library are searched for shared + libraries needed by it. The `DT_RPATH' entries are ignored if + `DT_RUNPATH' entries exist. + + 7. The default directories, normally `/lib' and `/usr/lib'. + + 8. For a native linker on an ELF system, if the file + `/etc/ld.so.conf' exists, the list of directories found in + that file. + + If the required shared library is not found, the linker will issue + a warning and continue with the link. + +`-shared' +`-Bshareable' + Create a shared library. This is currently only supported on ELF, + XCOFF and SunOS platforms. On SunOS, the linker will + automatically create a shared library if the `-e' option is not + used and there are undefined symbols in the link. + +`--sort-common' +`--sort-common=ascending' +`--sort-common=descending' + This option tells `ld' to sort the common symbols by alignment in + ascending or descending order when it places them in the + appropriate output sections. The symbol alignments considered are + sixteen-byte or larger, eight-byte, four-byte, two-byte, and + one-byte. This is to prevent gaps between symbols due to alignment + constraints. If no sorting order is specified, then descending + order is assumed. + +`--sort-section=name' + This option will apply `SORT_BY_NAME' to all wildcard section + patterns in the linker script. + +`--sort-section=alignment' + This option will apply `SORT_BY_ALIGNMENT' to all wildcard section + patterns in the linker script. + +`--split-by-file[=SIZE]' + Similar to `--split-by-reloc' but creates a new output section for + each input file when SIZE is reached. SIZE defaults to a size of + 1 if not given. + +`--split-by-reloc[=COUNT]' + Tries to creates extra sections in the output file so that no + single output section in the file contains more than COUNT + relocations. This is useful when generating huge relocatable + files for downloading into certain real time kernels with the COFF + object file format; since COFF cannot represent more than 65535 + relocations in a single section. Note that this will fail to work + with object file formats which do not support arbitrary sections. + The linker will not split up individual input sections for + redistribution, so if a single input section contains more than + COUNT relocations one output section will contain that many + relocations. COUNT defaults to a value of 32768. + +`--stats' + Compute and display statistics about the operation of the linker, + such as execution time and memory usage. + +`--sysroot=DIRECTORY' + Use DIRECTORY as the location of the sysroot, overriding the + configure-time default. This option is only supported by linkers + that were configured using `--with-sysroot'. + +`--traditional-format' + For some targets, the output of `ld' is different in some ways from + the output of some existing linker. This switch requests `ld' to + use the traditional format instead. + + For example, on SunOS, `ld' combines duplicate entries in the + symbol string table. This can reduce the size of an output file + with full debugging information by over 30 percent. + Unfortunately, the SunOS `dbx' program can not read the resulting + program (`gdb' has no trouble). The `--traditional-format' switch + tells `ld' to not combine duplicate entries. + +`--section-start=SECTIONNAME=ORG' + Locate a section in the output file at the absolute address given + by ORG. You may use this option as many times as necessary to + locate multiple sections in the command line. ORG must be a + single hexadecimal integer; for compatibility with other linkers, + you may omit the leading `0x' usually associated with hexadecimal + values. _Note:_ there should be no white space between + SECTIONNAME, the equals sign ("<=>"), and ORG. + +`-Tbss=ORG' +`-Tdata=ORG' +`-Ttext=ORG' + Same as `--section-start', with `.bss', `.data' or `.text' as the + SECTIONNAME. + +`-Ttext-segment=ORG' + When creating an ELF executable or shared object, it will set the + address of the first byte of the text segment. + +`--unresolved-symbols=METHOD' + Determine how to handle unresolved symbols. There are four + possible values for `method': + + `ignore-all' + Do not report any unresolved symbols. + + `report-all' + Report all unresolved symbols. This is the default. + + `ignore-in-object-files' + Report unresolved symbols that are contained in shared + libraries, but ignore them if they come from regular object + files. + + `ignore-in-shared-libs' + Report unresolved symbols that come from regular object + files, but ignore them if they come from shared libraries. + This can be useful when creating a dynamic binary and it is + known that all the shared libraries that it should be + referencing are included on the linker's command line. + + The behaviour for shared libraries on their own can also be + controlled by the `--[no-]allow-shlib-undefined' option. + + Normally the linker will generate an error message for each + reported unresolved symbol but the option + `--warn-unresolved-symbols' can change this to a warning. + +`--dll-verbose' +`--verbose' + Display the version number for `ld' and list the linker emulations + supported. Display which input files can and cannot be opened. + Display the linker script being used by the linker. + +`--version-script=VERSION-SCRIPTFILE' + Specify the name of a version script to the linker. This is + typically used when creating shared libraries to specify + additional information about the version hierarchy for the library + being created. This option is only fully supported on ELF + platforms which support shared libraries; see *Note VERSION::. It + is partially supported on PE platforms, which can use version + scripts to filter symbol visibility in auto-export mode: any + symbols marked `local' in the version script will not be exported. + *Note WIN32::. + +`--warn-common' + Warn when a common symbol is combined with another common symbol + or with a symbol definition. Unix linkers allow this somewhat + sloppy practise, but linkers on some other operating systems do + not. This option allows you to find potential problems from + combining global symbols. Unfortunately, some C libraries use + this practise, so you may get some warnings about symbols in the + libraries as well as in your programs. + + There are three kinds of global symbols, illustrated here by C + examples: + + `int i = 1;' + A definition, which goes in the initialized data section of + the output file. + + `extern int i;' + An undefined reference, which does not allocate space. There + must be either a definition or a common symbol for the + variable somewhere. + + `int i;' + A common symbol. If there are only (one or more) common + symbols for a variable, it goes in the uninitialized data + area of the output file. The linker merges multiple common + symbols for the same variable into a single symbol. If they + are of different sizes, it picks the largest size. The + linker turns a common symbol into a declaration, if there is + a definition of the same variable. + + The `--warn-common' option can produce five kinds of warnings. + Each warning consists of a pair of lines: the first describes the + symbol just encountered, and the second describes the previous + symbol encountered with the same name. One or both of the two + symbols will be a common symbol. + + 1. Turning a common symbol into a reference, because there is + already a definition for the symbol. + FILE(SECTION): warning: common of `SYMBOL' + overridden by definition + FILE(SECTION): warning: defined here + + 2. Turning a common symbol into a reference, because a later + definition for the symbol is encountered. This is the same + as the previous case, except that the symbols are encountered + in a different order. + FILE(SECTION): warning: definition of `SYMBOL' + overriding common + FILE(SECTION): warning: common is here + + 3. Merging a common symbol with a previous same-sized common + symbol. + FILE(SECTION): warning: multiple common + of `SYMBOL' + FILE(SECTION): warning: previous common is here + + 4. Merging a common symbol with a previous larger common symbol. + FILE(SECTION): warning: common of `SYMBOL' + overridden by larger common + FILE(SECTION): warning: larger common is here + + 5. Merging a common symbol with a previous smaller common + symbol. This is the same as the previous case, except that + the symbols are encountered in a different order. + FILE(SECTION): warning: common of `SYMBOL' + overriding smaller common + FILE(SECTION): warning: smaller common is here + +`--warn-constructors' + Warn if any global constructors are used. This is only useful for + a few object file formats. For formats like COFF or ELF, the + linker can not detect the use of global constructors. + +`--warn-multiple-gp' + Warn if multiple global pointer values are required in the output + file. This is only meaningful for certain processors, such as the + Alpha. Specifically, some processors put large-valued constants + in a special section. A special register (the global pointer) + points into the middle of this section, so that constants can be + loaded efficiently via a base-register relative addressing mode. + Since the offset in base-register relative mode is fixed and + relatively small (e.g., 16 bits), this limits the maximum size of + the constant pool. Thus, in large programs, it is often necessary + to use multiple global pointer values in order to be able to + address all possible constants. This option causes a warning to + be issued whenever this case occurs. + +`--warn-once' + Only warn once for each undefined symbol, rather than once per + module which refers to it. + +`--warn-section-align' + Warn if the address of an output section is changed because of + alignment. Typically, the alignment will be set by an input + section. The address will only be changed if it not explicitly + specified; that is, if the `SECTIONS' command does not specify a + start address for the section (*note SECTIONS::). + +`--warn-shared-textrel' + Warn if the linker adds a DT_TEXTREL to a shared object. + +`--warn-alternate-em' + Warn if an object has alternate ELF machine code. + +`--warn-unresolved-symbols' + If the linker is going to report an unresolved symbol (see the + option `--unresolved-symbols') it will normally generate an error. + This option makes it generate a warning instead. + +`--error-unresolved-symbols' + This restores the linker's default behaviour of generating errors + when it is reporting unresolved symbols. + +`--whole-archive' + For each archive mentioned on the command line after the + `--whole-archive' option, include every object file in the archive + in the link, rather than searching the archive for the required + object files. This is normally used to turn an archive file into + a shared library, forcing every object to be included in the + resulting shared library. This option may be used more than once. + + Two notes when using this option from gcc: First, gcc doesn't know + about this option, so you have to use `-Wl,-whole-archive'. + Second, don't forget to use `-Wl,-no-whole-archive' after your + list of archives, because gcc will add its own list of archives to + your link and you may not want this flag to affect those as well. + +`--wrap=SYMBOL' + Use a wrapper function for SYMBOL. Any undefined reference to + SYMBOL will be resolved to `__wrap_SYMBOL'. Any undefined + reference to `__real_SYMBOL' will be resolved to SYMBOL. + + This can be used to provide a wrapper for a system function. The + wrapper function should be called `__wrap_SYMBOL'. If it wishes + to call the system function, it should call `__real_SYMBOL'. + + Here is a trivial example: + + void * + __wrap_malloc (size_t c) + { + printf ("malloc called with %zu\n", c); + return __real_malloc (c); + } + + If you link other code with this file using `--wrap malloc', then + all calls to `malloc' will call the function `__wrap_malloc' + instead. The call to `__real_malloc' in `__wrap_malloc' will call + the real `malloc' function. + + You may wish to provide a `__real_malloc' function as well, so that + links without the `--wrap' option will succeed. If you do this, + you should not put the definition of `__real_malloc' in the same + file as `__wrap_malloc'; if you do, the assembler may resolve the + call before the linker has a chance to wrap it to `malloc'. + +`--eh-frame-hdr' + Request creation of `.eh_frame_hdr' section and ELF + `PT_GNU_EH_FRAME' segment header. + +`--enable-new-dtags' +`--disable-new-dtags' + This linker can create the new dynamic tags in ELF. But the older + ELF systems may not understand them. If you specify + `--enable-new-dtags', the dynamic tags will be created as needed. + If you specify `--disable-new-dtags', no new dynamic tags will be + created. By default, the new dynamic tags are not created. Note + that those options are only available for ELF systems. + +`--hash-size=NUMBER' + Set the default size of the linker's hash tables to a prime number + close to NUMBER. Increasing this value can reduce the length of + time it takes the linker to perform its tasks, at the expense of + increasing the linker's memory requirements. Similarly reducing + this value can reduce the memory requirements at the expense of + speed. + +`--hash-style=STYLE' + Set the type of linker's hash table(s). STYLE can be either + `sysv' for classic ELF `.hash' section, `gnu' for new style GNU + `.gnu.hash' section or `both' for both the classic ELF `.hash' and + new style GNU `.gnu.hash' hash tables. The default is `sysv'. + +`--reduce-memory-overheads' + This option reduces memory requirements at ld runtime, at the + expense of linking speed. This was introduced to select the old + O(n^2) algorithm for link map file generation, rather than the new + O(n) algorithm which uses about 40% more memory for symbol storage. + + Another effect of the switch is to set the default hash table size + to 1021, which again saves memory at the cost of lengthening the + linker's run time. This is not done however if the `--hash-size' + switch has been used. + + The `--reduce-memory-overheads' switch may be also be used to + enable other tradeoffs in future versions of the linker. + +`--build-id' +`--build-id=STYLE' + Request creation of `.note.gnu.build-id' ELF note section. The + contents of the note are unique bits identifying this linked file. + STYLE can be `uuid' to use 128 random bits, `sha1' to use a + 160-bit SHA1 hash on the normative parts of the output contents, + `md5' to use a 128-bit MD5 hash on the normative parts of the + output contents, or `0xHEXSTRING' to use a chosen bit string + specified as an even number of hexadecimal digits (`-' and `:' + characters between digit pairs are ignored). If STYLE is omitted, + `sha1' is used. + + The `md5' and `sha1' styles produces an identifier that is always + the same in an identical output file, but will be unique among all + nonidentical output files. It is not intended to be compared as a + checksum for the file's contents. A linked file may be changed + later by other tools, but the build ID bit string identifying the + original linked file does not change. + + Passing `none' for STYLE disables the setting from any + `--build-id' options earlier on the command line. + +2.1.1 Options Specific to i386 PE Targets +----------------------------------------- + +The i386 PE linker supports the `-shared' option, which causes the +output to be a dynamically linked library (DLL) instead of a normal +executable. You should name the output `*.dll' when you use this +option. In addition, the linker fully supports the standard `*.def' +files, which may be specified on the linker command line like an object +file (in fact, it should precede archives it exports symbols from, to +ensure that they get linked in, just like a normal object file). + + In addition to the options common to all targets, the i386 PE linker +support additional command line options that are specific to the i386 +PE target. Options that take values may be separated from their values +by either a space or an equals sign. + +`--add-stdcall-alias' + If given, symbols with a stdcall suffix (@NN) will be exported + as-is and also with the suffix stripped. [This option is specific + to the i386 PE targeted port of the linker] + +`--base-file FILE' + Use FILE as the name of a file in which to save the base addresses + of all the relocations needed for generating DLLs with `dlltool'. + [This is an i386 PE specific option] + +`--dll' + Create a DLL instead of a regular executable. You may also use + `-shared' or specify a `LIBRARY' in a given `.def' file. [This + option is specific to the i386 PE targeted port of the linker] + +`--enable-long-section-names' +`--disable-long-section-names' + The PE variants of the Coff object format add an extension that + permits the use of section names longer than eight characters, the + normal limit for Coff. By default, these names are only allowed + in object files, as fully-linked executable images do not carry + the Coff string table required to support the longer names. As a + GNU extension, it is possible to allow their use in executable + images as well, or to (probably pointlessly!) disallow it in + object files, by using these two options. Executable images + generated with these long section names are slightly non-standard, + carrying as they do a string table, and may generate confusing + output when examined with non-GNU PE-aware tools, such as file + viewers and dumpers. However, GDB relies on the use of PE long + section names to find Dwarf-2 debug information sections in an + executable image at runtime, and so if neither option is specified + on the command-line, `ld' will enable long section names, + overriding the default and technically correct behaviour, when it + finds the presence of debug information while linking an executable + image and not stripping symbols. [This option is valid for all PE + targeted ports of the linker] + +`--enable-stdcall-fixup' +`--disable-stdcall-fixup' + If the link finds a symbol that it cannot resolve, it will attempt + to do "fuzzy linking" by looking for another defined symbol that + differs only in the format of the symbol name (cdecl vs stdcall) + and will resolve that symbol by linking to the match. For + example, the undefined symbol `_foo' might be linked to the + function `_foo@12', or the undefined symbol `_bar@16' might be + linked to the function `_bar'. When the linker does this, it + prints a warning, since it normally should have failed to link, + but sometimes import libraries generated from third-party dlls may + need this feature to be usable. If you specify + `--enable-stdcall-fixup', this feature is fully enabled and + warnings are not printed. If you specify + `--disable-stdcall-fixup', this feature is disabled and such + mismatches are considered to be errors. [This option is specific + to the i386 PE targeted port of the linker] + +`--export-all-symbols' + If given, all global symbols in the objects used to build a DLL + will be exported by the DLL. Note that this is the default if + there otherwise wouldn't be any exported symbols. When symbols are + explicitly exported via DEF files or implicitly exported via + function attributes, the default is to not export anything else + unless this option is given. Note that the symbols `DllMain@12', + `DllEntryPoint@0', `DllMainCRTStartup@12', and `impure_ptr' will + not be automatically exported. Also, symbols imported from other + DLLs will not be re-exported, nor will symbols specifying the + DLL's internal layout such as those beginning with `_head_' or + ending with `_iname'. In addition, no symbols from `libgcc', + `libstd++', `libmingw32', or `crtX.o' will be exported. Symbols + whose names begin with `__rtti_' or `__builtin_' will not be + exported, to help with C++ DLLs. Finally, there is an extensive + list of cygwin-private symbols that are not exported (obviously, + this applies on when building DLLs for cygwin targets). These + cygwin-excludes are: `_cygwin_dll_entry@12', + `_cygwin_crt0_common@8', `_cygwin_noncygwin_dll_entry@12', + `_fmode', `_impure_ptr', `cygwin_attach_dll', `cygwin_premain0', + `cygwin_premain1', `cygwin_premain2', `cygwin_premain3', and + `environ'. [This option is specific to the i386 PE targeted port + of the linker] + +`--exclude-symbols SYMBOL,SYMBOL,...' + Specifies a list of symbols which should not be automatically + exported. The symbol names may be delimited by commas or colons. + [This option is specific to the i386 PE targeted port of the + linker] + +`--file-alignment' + Specify the file alignment. Sections in the file will always + begin at file offsets which are multiples of this number. This + defaults to 512. [This option is specific to the i386 PE targeted + port of the linker] + +`--heap RESERVE' +`--heap RESERVE,COMMIT' + Specify the number of bytes of memory to reserve (and optionally + commit) to be used as heap for this program. The default is 1Mb + reserved, 4K committed. [This option is specific to the i386 PE + targeted port of the linker] + +`--image-base VALUE' + Use VALUE as the base address of your program or dll. This is the + lowest memory location that will be used when your program or dll + is loaded. To reduce the need to relocate and improve performance + of your dlls, each should have a unique base address and not + overlap any other dlls. The default is 0x400000 for executables, + and 0x10000000 for dlls. [This option is specific to the i386 PE + targeted port of the linker] + +`--kill-at' + If given, the stdcall suffixes (@NN) will be stripped from symbols + before they are exported. [This option is specific to the i386 PE + targeted port of the linker] + +`--large-address-aware' + If given, the appropriate bit in the "Characteristics" field of + the COFF header is set to indicate that this executable supports + virtual addresses greater than 2 gigabytes. This should be used + in conjunction with the /3GB or /USERVA=VALUE megabytes switch in + the "[operating systems]" section of the BOOT.INI. Otherwise, + this bit has no effect. [This option is specific to PE targeted + ports of the linker] + +`--major-image-version VALUE' + Sets the major number of the "image version". Defaults to 1. + [This option is specific to the i386 PE targeted port of the + linker] + +`--major-os-version VALUE' + Sets the major number of the "os version". Defaults to 4. [This + option is specific to the i386 PE targeted port of the linker] + +`--major-subsystem-version VALUE' + Sets the major number of the "subsystem version". Defaults to 4. + [This option is specific to the i386 PE targeted port of the + linker] + +`--minor-image-version VALUE' + Sets the minor number of the "image version". Defaults to 0. + [This option is specific to the i386 PE targeted port of the + linker] + +`--minor-os-version VALUE' + Sets the minor number of the "os version". Defaults to 0. [This + option is specific to the i386 PE targeted port of the linker] + +`--minor-subsystem-version VALUE' + Sets the minor number of the "subsystem version". Defaults to 0. + [This option is specific to the i386 PE targeted port of the + linker] + +`--output-def FILE' + The linker will create the file FILE which will contain a DEF file + corresponding to the DLL the linker is generating. This DEF file + (which should be called `*.def') may be used to create an import + library with `dlltool' or may be used as a reference to + automatically or implicitly exported symbols. [This option is + specific to the i386 PE targeted port of the linker] + +`--out-implib FILE' + The linker will create the file FILE which will contain an import + lib corresponding to the DLL the linker is generating. This import + lib (which should be called `*.dll.a' or `*.a' may be used to link + clients against the generated DLL; this behaviour makes it + possible to skip a separate `dlltool' import library creation step. + [This option is specific to the i386 PE targeted port of the + linker] + +`--enable-auto-image-base' + Automatically choose the image base for DLLs, unless one is + specified using the `--image-base' argument. By using a hash + generated from the dllname to create unique image bases for each + DLL, in-memory collisions and relocations which can delay program + execution are avoided. [This option is specific to the i386 PE + targeted port of the linker] + +`--disable-auto-image-base' + Do not automatically generate a unique image base. If there is no + user-specified image base (`--image-base') then use the platform + default. [This option is specific to the i386 PE targeted port of + the linker] + +`--dll-search-prefix STRING' + When linking dynamically to a dll without an import library, + search for `<string><basename>.dll' in preference to + `lib<basename>.dll'. This behaviour allows easy distinction + between DLLs built for the various "subplatforms": native, cygwin, + uwin, pw, etc. For instance, cygwin DLLs typically use + `--dll-search-prefix=cyg'. [This option is specific to the i386 + PE targeted port of the linker] + +`--enable-auto-import' + Do sophisticated linking of `_symbol' to `__imp__symbol' for DATA + imports from DLLs, and create the necessary thunking symbols when + building the import libraries with those DATA exports. Note: Use + of the 'auto-import' extension will cause the text section of the + image file to be made writable. This does not conform to the + PE-COFF format specification published by Microsoft. + + Note - use of the 'auto-import' extension will also cause read only + data which would normally be placed into the .rdata section to be + placed into the .data section instead. This is in order to work + around a problem with consts that is described here: + http://www.cygwin.com/ml/cygwin/2004-09/msg01101.html + + Using 'auto-import' generally will 'just work' - but sometimes you + may see this message: + + "variable '<var>' can't be auto-imported. Please read the + documentation for ld's `--enable-auto-import' for details." + + This message occurs when some (sub)expression accesses an address + ultimately given by the sum of two constants (Win32 import tables + only allow one). Instances where this may occur include accesses + to member fields of struct variables imported from a DLL, as well + as using a constant index into an array variable imported from a + DLL. Any multiword variable (arrays, structs, long long, etc) may + trigger this error condition. However, regardless of the exact + data type of the offending exported variable, ld will always + detect it, issue the warning, and exit. + + There are several ways to address this difficulty, regardless of + the data type of the exported variable: + + One way is to use -enable-runtime-pseudo-reloc switch. This leaves + the task of adjusting references in your client code for runtime + environment, so this method works only when runtime environment + supports this feature. + + A second solution is to force one of the 'constants' to be a + variable - that is, unknown and un-optimizable at compile time. + For arrays, there are two possibilities: a) make the indexee (the + array's address) a variable, or b) make the 'constant' index a + variable. Thus: + + extern type extern_array[]; + extern_array[1] --> + { volatile type *t=extern_array; t[1] } + + or + + extern type extern_array[]; + extern_array[1] --> + { volatile int t=1; extern_array[t] } + + For structs (and most other multiword data types) the only option + is to make the struct itself (or the long long, or the ...) + variable: + + extern struct s extern_struct; + extern_struct.field --> + { volatile struct s *t=&extern_struct; t->field } + + or + + extern long long extern_ll; + extern_ll --> + { volatile long long * local_ll=&extern_ll; *local_ll } + + A third method of dealing with this difficulty is to abandon + 'auto-import' for the offending symbol and mark it with + `__declspec(dllimport)'. However, in practise that requires using + compile-time #defines to indicate whether you are building a DLL, + building client code that will link to the DLL, or merely + building/linking to a static library. In making the choice + between the various methods of resolving the 'direct address with + constant offset' problem, you should consider typical real-world + usage: + + Original: + --foo.h + extern int arr[]; + --foo.c + #include "foo.h" + void main(int argc, char **argv){ + printf("%d\n",arr[1]); + } + + Solution 1: + --foo.h + extern int arr[]; + --foo.c + #include "foo.h" + void main(int argc, char **argv){ + /* This workaround is for win32 and cygwin; do not "optimize" */ + volatile int *parr = arr; + printf("%d\n",parr[1]); + } + + Solution 2: + --foo.h + /* Note: auto-export is assumed (no __declspec(dllexport)) */ + #if (defined(_WIN32) || defined(__CYGWIN__)) && \ + !(defined(FOO_BUILD_DLL) || defined(FOO_STATIC)) + #define FOO_IMPORT __declspec(dllimport) + #else + #define FOO_IMPORT + #endif + extern FOO_IMPORT int arr[]; + --foo.c + #include "foo.h" + void main(int argc, char **argv){ + printf("%d\n",arr[1]); + } + + A fourth way to avoid this problem is to re-code your library to + use a functional interface rather than a data interface for the + offending variables (e.g. set_foo() and get_foo() accessor + functions). [This option is specific to the i386 PE targeted port + of the linker] + +`--disable-auto-import' + Do not attempt to do sophisticated linking of `_symbol' to + `__imp__symbol' for DATA imports from DLLs. [This option is + specific to the i386 PE targeted port of the linker] + +`--enable-runtime-pseudo-reloc' + If your code contains expressions described in -enable-auto-import + section, that is, DATA imports from DLL with non-zero offset, this + switch will create a vector of 'runtime pseudo relocations' which + can be used by runtime environment to adjust references to such + data in your client code. [This option is specific to the i386 PE + targeted port of the linker] + +`--disable-runtime-pseudo-reloc' + Do not create pseudo relocations for non-zero offset DATA imports + from DLLs. This is the default. [This option is specific to the + i386 PE targeted port of the linker] + +`--enable-extra-pe-debug' + Show additional debug info related to auto-import symbol thunking. + [This option is specific to the i386 PE targeted port of the + linker] + +`--section-alignment' + Sets the section alignment. Sections in memory will always begin + at addresses which are a multiple of this number. Defaults to + 0x1000. [This option is specific to the i386 PE targeted port of + the linker] + +`--stack RESERVE' +`--stack RESERVE,COMMIT' + Specify the number of bytes of memory to reserve (and optionally + commit) to be used as stack for this program. The default is 2Mb + reserved, 4K committed. [This option is specific to the i386 PE + targeted port of the linker] + +`--subsystem WHICH' +`--subsystem WHICH:MAJOR' +`--subsystem WHICH:MAJOR.MINOR' + Specifies the subsystem under which your program will execute. The + legal values for WHICH are `native', `windows', `console', + `posix', and `xbox'. You may optionally set the subsystem version + also. Numeric values are also accepted for WHICH. [This option + is specific to the i386 PE targeted port of the linker] + + The following options set flags in the `DllCharacteristics' field + of the PE file header: [These options are specific to PE targeted + ports of the linker] + +`--dynamicbase' + The image base address may be relocated using address space layout + randomization (ASLR). This feature was introduced with MS Windows + Vista for i386 PE targets. + +`--forceinteg' + Code integrity checks are enforced. + +`--nxcompat' + The image is compatible with the Data Execution Prevention. This + feature was introduced with MS Windows XP SP2 for i386 PE targets. + +`--no-isolation' + Although the image understands isolation, do not isolate the image. + +`--no-seh' + The image does not use SEH. No SE handler may be called from this + image. + +`--no-bind' + Do not bind this image. + +`--wdmdriver' + The driver uses the MS Windows Driver Model. + +`--tsaware' + The image is Terminal Server aware. + + +2.1.2 Options specific to Motorola 68HC11 and 68HC12 targets +------------------------------------------------------------ + +The 68HC11 and 68HC12 linkers support specific options to control the +memory bank switching mapping and trampoline code generation. + +`--no-trampoline' + This option disables the generation of trampoline. By default a + trampoline is generated for each far function which is called + using a `jsr' instruction (this happens when a pointer to a far + function is taken). + +`--bank-window NAME' + This option indicates to the linker the name of the memory region + in the `MEMORY' specification that describes the memory bank + window. The definition of such region is then used by the linker + to compute paging and addresses within the memory window. + + +2.1.3 Options specific to Motorola 68K target +--------------------------------------------- + +The following options are supported to control handling of GOT +generation when linking for 68K targets. + +`--got=TYPE' + This option tells the linker which GOT generation scheme to use. + TYPE should be one of `single', `negative', `multigot' or + `target'. For more information refer to the Info entry for `ld'. + + + +File: ld.info, Node: Environment, Prev: Options, Up: Invocation + +2.2 Environment Variables +========================= + +You can change the behaviour of `ld' with the environment variables +`GNUTARGET', `LDEMULATION' and `COLLECT_NO_DEMANGLE'. + + `GNUTARGET' determines the input-file object format if you don't use +`-b' (or its synonym `--format'). Its value should be one of the BFD +names for an input format (*note BFD::). If there is no `GNUTARGET' in +the environment, `ld' uses the natural format of the target. If +`GNUTARGET' is set to `default' then BFD attempts to discover the input +format by examining binary input files; this method often succeeds, but +there are potential ambiguities, since there is no method of ensuring +that the magic number used to specify object-file formats is unique. +However, the configuration procedure for BFD on each system places the +conventional format for that system first in the search-list, so +ambiguities are resolved in favor of convention. + + `LDEMULATION' determines the default emulation if you don't use the +`-m' option. The emulation can affect various aspects of linker +behaviour, particularly the default linker script. You can list the +available emulations with the `--verbose' or `-V' options. If the `-m' +option is not used, and the `LDEMULATION' environment variable is not +defined, the default emulation depends upon how the linker was +configured. + + Normally, the linker will default to demangling symbols. However, if +`COLLECT_NO_DEMANGLE' is set in the environment, then it will default +to not demangling symbols. This environment variable is used in a +similar fashion by the `gcc' linker wrapper program. The default may +be overridden by the `--demangle' and `--no-demangle' options. + + +File: ld.info, Node: Scripts, Next: Machine Dependent, Prev: Invocation, Up: Top + +3 Linker Scripts +**************** + +Every link is controlled by a "linker script". This script is written +in the linker command language. + + The main purpose of the linker script is to describe how the +sections in the input files should be mapped into the output file, and +to control the memory layout of the output file. Most linker scripts +do nothing more than this. However, when necessary, the linker script +can also direct the linker to perform many other operations, using the +commands described below. + + The linker always uses a linker script. If you do not supply one +yourself, the linker will use a default script that is compiled into the +linker executable. You can use the `--verbose' command line option to +display the default linker script. Certain command line options, such +as `-r' or `-N', will affect the default linker script. + + You may supply your own linker script by using the `-T' command line +option. When you do this, your linker script will replace the default +linker script. + + You may also use linker scripts implicitly by naming them as input +files to the linker, as though they were files to be linked. *Note +Implicit Linker Scripts::. + +* Menu: + +* Basic Script Concepts:: Basic Linker Script Concepts +* Script Format:: Linker Script Format +* Simple Example:: Simple Linker Script Example +* Simple Commands:: Simple Linker Script Commands +* Assignments:: Assigning Values to Symbols +* SECTIONS:: SECTIONS Command +* MEMORY:: MEMORY Command +* PHDRS:: PHDRS Command +* VERSION:: VERSION Command +* Expressions:: Expressions in Linker Scripts +* Implicit Linker Scripts:: Implicit Linker Scripts + + +File: ld.info, Node: Basic Script Concepts, Next: Script Format, Up: Scripts + +3.1 Basic Linker Script Concepts +================================ + +We need to define some basic concepts and vocabulary in order to +describe the linker script language. + + The linker combines input files into a single output file. The +output file and each input file are in a special data format known as an +"object file format". Each file is called an "object file". The +output file is often called an "executable", but for our purposes we +will also call it an object file. Each object file has, among other +things, a list of "sections". We sometimes refer to a section in an +input file as an "input section"; similarly, a section in the output +file is an "output section". + + Each section in an object file has a name and a size. Most sections +also have an associated block of data, known as the "section contents". +A section may be marked as "loadable", which mean that the contents +should be loaded into memory when the output file is run. A section +with no contents may be "allocatable", which means that an area in +memory should be set aside, but nothing in particular should be loaded +there (in some cases this memory must be zeroed out). A section which +is neither loadable nor allocatable typically contains some sort of +debugging information. + + Every loadable or allocatable output section has two addresses. The +first is the "VMA", or virtual memory address. This is the address the +section will have when the output file is run. The second is the +"LMA", or load memory address. This is the address at which the +section will be loaded. In most cases the two addresses will be the +same. An example of when they might be different is when a data section +is loaded into ROM, and then copied into RAM when the program starts up +(this technique is often used to initialize global variables in a ROM +based system). In this case the ROM address would be the LMA, and the +RAM address would be the VMA. + + You can see the sections in an object file by using the `objdump' +program with the `-h' option. + + Every object file also has a list of "symbols", known as the "symbol +table". A symbol may be defined or undefined. Each symbol has a name, +and each defined symbol has an address, among other information. If +you compile a C or C++ program into an object file, you will get a +defined symbol for every defined function and global or static +variable. Every undefined function or global variable which is +referenced in the input file will become an undefined symbol. + + You can see the symbols in an object file by using the `nm' program, +or by using the `objdump' program with the `-t' option. + + +File: ld.info, Node: Script Format, Next: Simple Example, Prev: Basic Script Concepts, Up: Scripts + +3.2 Linker Script Format +======================== + +Linker scripts are text files. + + You write a linker script as a series of commands. Each command is +either a keyword, possibly followed by arguments, or an assignment to a +symbol. You may separate commands using semicolons. Whitespace is +generally ignored. + + Strings such as file or format names can normally be entered +directly. If the file name contains a character such as a comma which +would otherwise serve to separate file names, you may put the file name +in double quotes. There is no way to use a double quote character in a +file name. + + You may include comments in linker scripts just as in C, delimited by +`/*' and `*/'. As in C, comments are syntactically equivalent to +whitespace. + + +File: ld.info, Node: Simple Example, Next: Simple Commands, Prev: Script Format, Up: Scripts + +3.3 Simple Linker Script Example +================================ + +Many linker scripts are fairly simple. + + The simplest possible linker script has just one command: +`SECTIONS'. You use the `SECTIONS' command to describe the memory +layout of the output file. + + The `SECTIONS' command is a powerful command. Here we will describe +a simple use of it. Let's assume your program consists only of code, +initialized data, and uninitialized data. These will be in the +`.text', `.data', and `.bss' sections, respectively. Let's assume +further that these are the only sections which appear in your input +files. + + For this example, let's say that the code should be loaded at address +0x10000, and that the data should start at address 0x8000000. Here is a +linker script which will do that: + SECTIONS + { + . = 0x10000; + .text : { *(.text) } + . = 0x8000000; + .data : { *(.data) } + .bss : { *(.bss) } + } + + You write the `SECTIONS' command as the keyword `SECTIONS', followed +by a series of symbol assignments and output section descriptions +enclosed in curly braces. + + The first line inside the `SECTIONS' command of the above example +sets the value of the special symbol `.', which is the location +counter. If you do not specify the address of an output section in some +other way (other ways are described later), the address is set from the +current value of the location counter. The location counter is then +incremented by the size of the output section. At the start of the +`SECTIONS' command, the location counter has the value `0'. + + The second line defines an output section, `.text'. The colon is +required syntax which may be ignored for now. Within the curly braces +after the output section name, you list the names of the input sections +which should be placed into this output section. The `*' is a wildcard +which matches any file name. The expression `*(.text)' means all +`.text' input sections in all input files. + + Since the location counter is `0x10000' when the output section +`.text' is defined, the linker will set the address of the `.text' +section in the output file to be `0x10000'. + + The remaining lines define the `.data' and `.bss' sections in the +output file. The linker will place the `.data' output section at +address `0x8000000'. After the linker places the `.data' output +section, the value of the location counter will be `0x8000000' plus the +size of the `.data' output section. The effect is that the linker will +place the `.bss' output section immediately after the `.data' output +section in memory. + + The linker will ensure that each output section has the required +alignment, by increasing the location counter if necessary. In this +example, the specified addresses for the `.text' and `.data' sections +will probably satisfy any alignment constraints, but the linker may +have to create a small gap between the `.data' and `.bss' sections. + + That's it! That's a simple and complete linker script. + + +File: ld.info, Node: Simple Commands, Next: Assignments, Prev: Simple Example, Up: Scripts + +3.4 Simple Linker Script Commands +================================= + +In this section we describe the simple linker script commands. + +* Menu: + +* Entry Point:: Setting the entry point +* File Commands:: Commands dealing with files + +* Format Commands:: Commands dealing with object file formats + +* REGION_ALIAS:: Assign alias names to memory regions +* Miscellaneous Commands:: Other linker script commands + + +File: ld.info, Node: Entry Point, Next: File Commands, Up: Simple Commands + +3.4.1 Setting the Entry Point +----------------------------- + +The first instruction to execute in a program is called the "entry +point". You can use the `ENTRY' linker script command to set the entry +point. The argument is a symbol name: + ENTRY(SYMBOL) + + There are several ways to set the entry point. The linker will set +the entry point by trying each of the following methods in order, and +stopping when one of them succeeds: + * the `-e' ENTRY command-line option; + + * the `ENTRY(SYMBOL)' command in a linker script; + + * the value of the symbol `start', if defined; + + * the address of the first byte of the `.text' section, if present; + + * The address `0'. + + +File: ld.info, Node: File Commands, Next: Format Commands, Prev: Entry Point, Up: Simple Commands + +3.4.2 Commands Dealing with Files +--------------------------------- + +Several linker script commands deal with files. + +`INCLUDE FILENAME' + Include the linker script FILENAME at this point. The file will + be searched for in the current directory, and in any directory + specified with the `-L' option. You can nest calls to `INCLUDE' + up to 10 levels deep. + + You can place `INCLUDE' directives at the top level, in `MEMORY' or + `SECTIONS' commands, or in output section descriptions. + +`INPUT(FILE, FILE, ...)' +`INPUT(FILE FILE ...)' + The `INPUT' command directs the linker to include the named files + in the link, as though they were named on the command line. + + For example, if you always want to include `subr.o' any time you do + a link, but you can't be bothered to put it on every link command + line, then you can put `INPUT (subr.o)' in your linker script. + + In fact, if you like, you can list all of your input files in the + linker script, and then invoke the linker with nothing but a `-T' + option. + + In case a "sysroot prefix" is configured, and the filename starts + with the `/' character, and the script being processed was located + inside the "sysroot prefix", the filename will be looked for in + the "sysroot prefix". Otherwise, the linker will try to open the + file in the current directory. If it is not found, the linker + will search through the archive library search path. See the + description of `-L' in *Note Command Line Options: Options. + + If you use `INPUT (-lFILE)', `ld' will transform the name to + `libFILE.a', as with the command line argument `-l'. + + When you use the `INPUT' command in an implicit linker script, the + files will be included in the link at the point at which the linker + script file is included. This can affect archive searching. + +`GROUP(FILE, FILE, ...)' +`GROUP(FILE FILE ...)' + The `GROUP' command is like `INPUT', except that the named files + should all be archives, and they are searched repeatedly until no + new undefined references are created. See the description of `-(' + in *Note Command Line Options: Options. + +`AS_NEEDED(FILE, FILE, ...)' +`AS_NEEDED(FILE FILE ...)' + This construct can appear only inside of the `INPUT' or `GROUP' + commands, among other filenames. The files listed will be handled + as if they appear directly in the `INPUT' or `GROUP' commands, + with the exception of ELF shared libraries, that will be added only + when they are actually needed. This construct essentially enables + `--as-needed' option for all the files listed inside of it and + restores previous `--as-needed' resp. `--no-as-needed' setting + afterwards. + +`OUTPUT(FILENAME)' + The `OUTPUT' command names the output file. Using + `OUTPUT(FILENAME)' in the linker script is exactly like using `-o + FILENAME' on the command line (*note Command Line Options: + Options.). If both are used, the command line option takes + precedence. + + You can use the `OUTPUT' command to define a default name for the + output file other than the usual default of `a.out'. + +`SEARCH_DIR(PATH)' + The `SEARCH_DIR' command adds PATH to the list of paths where `ld' + looks for archive libraries. Using `SEARCH_DIR(PATH)' is exactly + like using `-L PATH' on the command line (*note Command Line + Options: Options.). If both are used, then the linker will search + both paths. Paths specified using the command line option are + searched first. + +`STARTUP(FILENAME)' + The `STARTUP' command is just like the `INPUT' command, except + that FILENAME will become the first input file to be linked, as + though it were specified first on the command line. This may be + useful when using a system in which the entry point is always the + start of the first file. + + +File: ld.info, Node: Format Commands, Next: REGION_ALIAS, Prev: File Commands, Up: Simple Commands + +3.4.3 Commands Dealing with Object File Formats +----------------------------------------------- + +A couple of linker script commands deal with object file formats. + +`OUTPUT_FORMAT(BFDNAME)' +`OUTPUT_FORMAT(DEFAULT, BIG, LITTLE)' + The `OUTPUT_FORMAT' command names the BFD format to use for the + output file (*note BFD::). Using `OUTPUT_FORMAT(BFDNAME)' is + exactly like using `--oformat BFDNAME' on the command line (*note + Command Line Options: Options.). If both are used, the command + line option takes precedence. + + You can use `OUTPUT_FORMAT' with three arguments to use different + formats based on the `-EB' and `-EL' command line options. This + permits the linker script to set the output format based on the + desired endianness. + + If neither `-EB' nor `-EL' are used, then the output format will + be the first argument, DEFAULT. If `-EB' is used, the output + format will be the second argument, BIG. If `-EL' is used, the + output format will be the third argument, LITTLE. + + For example, the default linker script for the MIPS ELF target + uses this command: + OUTPUT_FORMAT(elf32-bigmips, elf32-bigmips, elf32-littlemips) + This says that the default format for the output file is + `elf32-bigmips', but if the user uses the `-EL' command line + option, the output file will be created in the `elf32-littlemips' + format. + +`TARGET(BFDNAME)' + The `TARGET' command names the BFD format to use when reading input + files. It affects subsequent `INPUT' and `GROUP' commands. This + command is like using `-b BFDNAME' on the command line (*note + Command Line Options: Options.). If the `TARGET' command is used + but `OUTPUT_FORMAT' is not, then the last `TARGET' command is also + used to set the format for the output file. *Note BFD::. + + +File: ld.info, Node: REGION_ALIAS, Next: Miscellaneous Commands, Prev: Format Commands, Up: Simple Commands + +3.4.4 Assign alias names to memory regions +------------------------------------------ + +Alias names can be added to existing memory regions created with the +*Note MEMORY:: command. Each name corresponds to at most one memory +region. + + REGION_ALIAS(ALIAS, REGION) + + The `REGION_ALIAS' function creates an alias name ALIAS for the +memory region REGION. This allows a flexible mapping of output sections +to memory regions. An example follows. + + Suppose we have an application for embedded systems which come with +various memory storage devices. All have a general purpose, volatile +memory `RAM' that allows code execution or data storage. Some may have +a read-only, non-volatile memory `ROM' that allows code execution and +read-only data access. The last variant is a read-only, non-volatile +memory `ROM2' with read-only data access and no code execution +capability. We have four output sections: + + * `.text' program code; + + * `.rodata' read-only data; + + * `.data' read-write initialized data; + + * `.bss' read-write zero initialized data. + + The goal is to provide a linker command file that contains a system +independent part defining the output sections and a system dependent +part mapping the output sections to the memory regions available on the +system. Our embedded systems come with three different memory setups +`A', `B' and `C': +Section Variant A Variant B Variant C +.text RAM ROM ROM +.rodata RAM ROM ROM2 +.data RAM RAM/ROM RAM/ROM2 +.bss RAM RAM RAM + The notation `RAM/ROM' or `RAM/ROM2' means that this section is +loaded into region `ROM' or `ROM2' respectively. Please note that the +load address of the `.data' section starts in all three variants at the +end of the `.rodata' section. + + The base linker script that deals with the output sections follows. +It includes the system dependent `linkcmds.memory' file that describes +the memory layout: + INCLUDE linkcmds.memory + + SECTIONS + { + .text : + { + *(.text) + } > REGION_TEXT + .rodata : + { + *(.rodata) + rodata_end = .; + } > REGION_RODATA + .data : AT (rodata_end) + { + data_start = .; + *(.data) + } > REGION_DATA + data_size = SIZEOF(.data); + data_load_start = LOADADDR(.data); + .bss : + { + *(.bss) + } > REGION_BSS + } + + Now we need three different `linkcmds.memory' files to define memory +regions and alias names. The content of `linkcmds.memory' for the three +variants `A', `B' and `C': +`A' + Here everything goes into the `RAM'. + MEMORY + { + RAM : ORIGIN = 0, LENGTH = 4M + } + + REGION_ALIAS("REGION_TEXT", RAM); + REGION_ALIAS("REGION_RODATA", RAM); + REGION_ALIAS("REGION_DATA", RAM); + REGION_ALIAS("REGION_BSS", RAM); + +`B' + Program code and read-only data go into the `ROM'. Read-write + data goes into the `RAM'. An image of the initialized data is + loaded into the `ROM' and will be copied during system start into + the `RAM'. + MEMORY + { + ROM : ORIGIN = 0, LENGTH = 3M + RAM : ORIGIN = 0x10000000, LENGTH = 1M + } + + REGION_ALIAS("REGION_TEXT", ROM); + REGION_ALIAS("REGION_RODATA", ROM); + REGION_ALIAS("REGION_DATA", RAM); + REGION_ALIAS("REGION_BSS", RAM); + +`C' + Program code goes into the `ROM'. Read-only data goes into the + `ROM2'. Read-write data goes into the `RAM'. An image of the + initialized data is loaded into the `ROM2' and will be copied + during system start into the `RAM'. + MEMORY + { + ROM : ORIGIN = 0, LENGTH = 2M + ROM2 : ORIGIN = 0x10000000, LENGTH = 1M + RAM : ORIGIN = 0x20000000, LENGTH = 1M + } + + REGION_ALIAS("REGION_TEXT", ROM); + REGION_ALIAS("REGION_RODATA", ROM2); + REGION_ALIAS("REGION_DATA", RAM); + REGION_ALIAS("REGION_BSS", RAM); + + It is possible to write a common system initialization routine to +copy the `.data' section from `ROM' or `ROM2' into the `RAM' if +necessary: + #include <string.h> + + extern char data_start []; + extern char data_size []; + extern char data_load_start []; + + void copy_data(void) + { + if (data_start != data_load_start) + { + memcpy(data_start, data_load_start, (size_t) data_size); + } + } + + +File: ld.info, Node: Miscellaneous Commands, Prev: REGION_ALIAS, Up: Simple Commands + +3.4.5 Other Linker Script Commands +---------------------------------- + +There are a few other linker scripts commands. + +`ASSERT(EXP, MESSAGE)' + Ensure that EXP is non-zero. If it is zero, then exit the linker + with an error code, and print MESSAGE. + +`EXTERN(SYMBOL SYMBOL ...)' + Force SYMBOL to be entered in the output file as an undefined + symbol. Doing this may, for example, trigger linking of additional + modules from standard libraries. You may list several SYMBOLs for + each `EXTERN', and you may use `EXTERN' multiple times. This + command has the same effect as the `-u' command-line option. + +`FORCE_COMMON_ALLOCATION' + This command has the same effect as the `-d' command-line option: + to make `ld' assign space to common symbols even if a relocatable + output file is specified (`-r'). + +`INHIBIT_COMMON_ALLOCATION' + This command has the same effect as the `--no-define-common' + command-line option: to make `ld' omit the assignment of addresses + to common symbols even for a non-relocatable output file. + +`INSERT [ AFTER | BEFORE ] OUTPUT_SECTION' + This command is typically used in a script specified by `-T' to + augment the default `SECTIONS' with, for example, overlays. It + inserts all prior linker script statements after (or before) + OUTPUT_SECTION, and also causes `-T' to not override the default + linker script. The exact insertion point is as for orphan + sections. *Note Location Counter::. The insertion happens after + the linker has mapped input sections to output sections. Prior to + the insertion, since `-T' scripts are parsed before the default + linker script, statements in the `-T' script occur before the + default linker script statements in the internal linker + representation of the script. In particular, input section + assignments will be made to `-T' output sections before those in + the default script. Here is an example of how a `-T' script using + `INSERT' might look: + + SECTIONS + { + OVERLAY : + { + .ov1 { ov1*(.text) } + .ov2 { ov2*(.text) } + } + } + INSERT AFTER .text; + +`NOCROSSREFS(SECTION SECTION ...)' + This command may be used to tell `ld' to issue an error about any + references among certain output sections. + + In certain types of programs, particularly on embedded systems when + using overlays, when one section is loaded into memory, another + section will not be. Any direct references between the two + sections would be errors. For example, it would be an error if + code in one section called a function defined in the other section. + + The `NOCROSSREFS' command takes a list of output section names. If + `ld' detects any cross references between the sections, it reports + an error and returns a non-zero exit status. Note that the + `NOCROSSREFS' command uses output section names, not input section + names. + +`OUTPUT_ARCH(BFDARCH)' + Specify a particular output machine architecture. The argument is + one of the names used by the BFD library (*note BFD::). You can + see the architecture of an object file by using the `objdump' + program with the `-f' option. + + +File: ld.info, Node: Assignments, Next: SECTIONS, Prev: Simple Commands, Up: Scripts + +3.5 Assigning Values to Symbols +=============================== + +You may assign a value to a symbol in a linker script. This will define +the symbol and place it into the symbol table with a global scope. + +* Menu: + +* Simple Assignments:: Simple Assignments +* PROVIDE:: PROVIDE +* PROVIDE_HIDDEN:: PROVIDE_HIDDEN +* Source Code Reference:: How to use a linker script defined symbol in source code + + +File: ld.info, Node: Simple Assignments, Next: PROVIDE, Up: Assignments + +3.5.1 Simple Assignments +------------------------ + +You may assign to a symbol using any of the C assignment operators: + +`SYMBOL = EXPRESSION ;' +`SYMBOL += EXPRESSION ;' +`SYMBOL -= EXPRESSION ;' +`SYMBOL *= EXPRESSION ;' +`SYMBOL /= EXPRESSION ;' +`SYMBOL <<= EXPRESSION ;' +`SYMBOL >>= EXPRESSION ;' +`SYMBOL &= EXPRESSION ;' +`SYMBOL |= EXPRESSION ;' + + The first case will define SYMBOL to the value of EXPRESSION. In +the other cases, SYMBOL must already be defined, and the value will be +adjusted accordingly. + + The special symbol name `.' indicates the location counter. You may +only use this within a `SECTIONS' command. *Note Location Counter::. + + The semicolon after EXPRESSION is required. + + Expressions are defined below; see *Note Expressions::. + + You may write symbol assignments as commands in their own right, or +as statements within a `SECTIONS' command, or as part of an output +section description in a `SECTIONS' command. + + The section of the symbol will be set from the section of the +expression; for more information, see *Note Expression Section::. + + Here is an example showing the three different places that symbol +assignments may be used: + + floating_point = 0; + SECTIONS + { + .text : + { + *(.text) + _etext = .; + } + _bdata = (. + 3) & ~ 3; + .data : { *(.data) } + } + In this example, the symbol `floating_point' will be defined as +zero. The symbol `_etext' will be defined as the address following the +last `.text' input section. The symbol `_bdata' will be defined as the +address following the `.text' output section aligned upward to a 4 byte +boundary. + + +File: ld.info, Node: PROVIDE, Next: PROVIDE_HIDDEN, Prev: Simple Assignments, Up: Assignments + +3.5.2 PROVIDE +------------- + +In some cases, it is desirable for a linker script to define a symbol +only if it is referenced and is not defined by any object included in +the link. For example, traditional linkers defined the symbol `etext'. +However, ANSI C requires that the user be able to use `etext' as a +function name without encountering an error. The `PROVIDE' keyword may +be used to define a symbol, such as `etext', only if it is referenced +but not defined. The syntax is `PROVIDE(SYMBOL = EXPRESSION)'. + + Here is an example of using `PROVIDE' to define `etext': + SECTIONS + { + .text : + { + *(.text) + _etext = .; + PROVIDE(etext = .); + } + } + + In this example, if the program defines `_etext' (with a leading +underscore), the linker will give a multiple definition error. If, on +the other hand, the program defines `etext' (with no leading +underscore), the linker will silently use the definition in the program. +If the program references `etext' but does not define it, the linker +will use the definition in the linker script. + + +File: ld.info, Node: PROVIDE_HIDDEN, Next: Source Code Reference, Prev: PROVIDE, Up: Assignments + +3.5.3 PROVIDE_HIDDEN +-------------------- + +Similar to `PROVIDE'. For ELF targeted ports, the symbol will be +hidden and won't be exported. + + +File: ld.info, Node: Source Code Reference, Prev: PROVIDE_HIDDEN, Up: Assignments + +3.5.4 Source Code Reference +--------------------------- + +Accessing a linker script defined variable from source code is not +intuitive. In particular a linker script symbol is not equivalent to a +variable declaration in a high level language, it is instead a symbol +that does not have a value. + + Before going further, it is important to note that compilers often +transform names in the source code into different names when they are +stored in the symbol table. For example, Fortran compilers commonly +prepend or append an underscore, and C++ performs extensive `name +mangling'. Therefore there might be a discrepancy between the name of +a variable as it is used in source code and the name of the same +variable as it is defined in a linker script. For example in C a +linker script variable might be referred to as: + + extern int foo; + + But in the linker script it might be defined as: + + _foo = 1000; + + In the remaining examples however it is assumed that no name +transformation has taken place. + + When a symbol is declared in a high level language such as C, two +things happen. The first is that the compiler reserves enough space in +the program's memory to hold the _value_ of the symbol. The second is +that the compiler creates an entry in the program's symbol table which +holds the symbol's _address_. ie the symbol table contains the address +of the block of memory holding the symbol's value. So for example the +following C declaration, at file scope: + + int foo = 1000; + + creates a entry called `foo' in the symbol table. This entry holds +the address of an `int' sized block of memory where the number 1000 is +initially stored. + + When a program references a symbol the compiler generates code that +first accesses the symbol table to find the address of the symbol's +memory block and then code to read the value from that memory block. +So: + + foo = 1; + + looks up the symbol `foo' in the symbol table, gets the address +associated with this symbol and then writes the value 1 into that +address. Whereas: + + int * a = & foo; + + looks up the symbol `foo' in the symbol table, gets it address and +then copies this address into the block of memory associated with the +variable `a'. + + Linker scripts symbol declarations, by contrast, create an entry in +the symbol table but do not assign any memory to them. Thus they are +an address without a value. So for example the linker script +definition: + + foo = 1000; + + creates an entry in the symbol table called `foo' which holds the +address of memory location 1000, but nothing special is stored at +address 1000. This means that you cannot access the _value_ of a +linker script defined symbol - it has no value - all you can do is +access the _address_ of a linker script defined symbol. + + Hence when you are using a linker script defined symbol in source +code you should always take the address of the symbol, and never +attempt to use its value. For example suppose you want to copy the +contents of a section of memory called .ROM into a section called +.FLASH and the linker script contains these declarations: + + start_of_ROM = .ROM; + end_of_ROM = .ROM + sizeof (.ROM) - 1; + start_of_FLASH = .FLASH; + + Then the C source code to perform the copy would be: + + extern char start_of_ROM, end_of_ROM, start_of_FLASH; + + memcpy (& start_of_FLASH, & start_of_ROM, & end_of_ROM - & start_of_ROM); + + Note the use of the `&' operators. These are correct. + + +File: ld.info, Node: SECTIONS, Next: MEMORY, Prev: Assignments, Up: Scripts + +3.6 SECTIONS Command +==================== + +The `SECTIONS' command tells the linker how to map input sections into +output sections, and how to place the output sections in memory. + + The format of the `SECTIONS' command is: + SECTIONS + { + SECTIONS-COMMAND + SECTIONS-COMMAND + ... + } + + Each SECTIONS-COMMAND may of be one of the following: + + * an `ENTRY' command (*note Entry command: Entry Point.) + + * a symbol assignment (*note Assignments::) + + * an output section description + + * an overlay description + + The `ENTRY' command and symbol assignments are permitted inside the +`SECTIONS' command for convenience in using the location counter in +those commands. This can also make the linker script easier to +understand because you can use those commands at meaningful points in +the layout of the output file. + + Output section descriptions and overlay descriptions are described +below. + + If you do not use a `SECTIONS' command in your linker script, the +linker will place each input section into an identically named output +section in the order that the sections are first encountered in the +input files. If all input sections are present in the first file, for +example, the order of sections in the output file will match the order +in the first input file. The first section will be at address zero. + +* Menu: + +* Output Section Description:: Output section description +* Output Section Name:: Output section name +* Output Section Address:: Output section address +* Input Section:: Input section description +* Output Section Data:: Output section data +* Output Section Keywords:: Output section keywords +* Output Section Discarding:: Output section discarding +* Output Section Attributes:: Output section attributes +* Overlay Description:: Overlay description + + +File: ld.info, Node: Output Section Description, Next: Output Section Name, Up: SECTIONS + +3.6.1 Output Section Description +-------------------------------- + +The full description of an output section looks like this: + SECTION [ADDRESS] [(TYPE)] : + [AT(LMA)] + [ALIGN(SECTION_ALIGN)] + [SUBALIGN(SUBSECTION_ALIGN)] + [CONSTRAINT] + { + OUTPUT-SECTION-COMMAND + OUTPUT-SECTION-COMMAND + ... + } [>REGION] [AT>LMA_REGION] [:PHDR :PHDR ...] [=FILLEXP] + + Most output sections do not use most of the optional section +attributes. + + The whitespace around SECTION is required, so that the section name +is unambiguous. The colon and the curly braces are also required. The +line breaks and other white space are optional. + + Each OUTPUT-SECTION-COMMAND may be one of the following: + + * a symbol assignment (*note Assignments::) + + * an input section description (*note Input Section::) + + * data values to include directly (*note Output Section Data::) + + * a special output section keyword (*note Output Section Keywords::) + + +File: ld.info, Node: Output Section Name, Next: Output Section Address, Prev: Output Section Description, Up: SECTIONS + +3.6.2 Output Section Name +------------------------- + +The name of the output section is SECTION. SECTION must meet the +constraints of your output format. In formats which only support a +limited number of sections, such as `a.out', the name must be one of +the names supported by the format (`a.out', for example, allows only +`.text', `.data' or `.bss'). If the output format supports any number +of sections, but with numbers and not names (as is the case for Oasys), +the name should be supplied as a quoted numeric string. A section name +may consist of any sequence of characters, but a name which contains +any unusual characters such as commas must be quoted. + + The output section name `/DISCARD/' is special; *Note Output Section +Discarding::. + + +File: ld.info, Node: Output Section Address, Next: Input Section, Prev: Output Section Name, Up: SECTIONS + +3.6.3 Output Section Address +---------------------------- + +The ADDRESS is an expression for the VMA (the virtual memory address) +of the output section. If you do not provide ADDRESS, the linker will +set it based on REGION if present, or otherwise based on the current +value of the location counter. + + If you provide ADDRESS, the address of the output section will be +set to precisely that. If you provide neither ADDRESS nor REGION, then +the address of the output section will be set to the current value of +the location counter aligned to the alignment requirements of the +output section. The alignment requirement of the output section is the +strictest alignment of any input section contained within the output +section. + + For example, + .text . : { *(.text) } + and + .text : { *(.text) } + are subtly different. The first will set the address of the `.text' +output section to the current value of the location counter. The +second will set it to the current value of the location counter aligned +to the strictest alignment of a `.text' input section. + + The ADDRESS may be an arbitrary expression; *Note Expressions::. +For example, if you want to align the section on a 0x10 byte boundary, +so that the lowest four bits of the section address are zero, you could +do something like this: + .text ALIGN(0x10) : { *(.text) } + This works because `ALIGN' returns the current location counter +aligned upward to the specified value. + + Specifying ADDRESS for a section will change the value of the +location counter, provided that the section is non-empty. (Empty +sections are ignored). + + +File: ld.info, Node: Input Section, Next: Output Section Data, Prev: Output Section Address, Up: SECTIONS + +3.6.4 Input Section Description +------------------------------- + +The most common output section command is an input section description. + + The input section description is the most basic linker script +operation. You use output sections to tell the linker how to lay out +your program in memory. You use input section descriptions to tell the +linker how to map the input files into your memory layout. + +* Menu: + +* Input Section Basics:: Input section basics +* Input Section Wildcards:: Input section wildcard patterns +* Input Section Common:: Input section for common symbols +* Input Section Keep:: Input section and garbage collection +* Input Section Example:: Input section example + + +File: ld.info, Node: Input Section Basics, Next: Input Section Wildcards, Up: Input Section + +3.6.4.1 Input Section Basics +............................ + +An input section description consists of a file name optionally followed +by a list of section names in parentheses. + + The file name and the section name may be wildcard patterns, which we +describe further below (*note Input Section Wildcards::). + + The most common input section description is to include all input +sections with a particular name in the output section. For example, to +include all input `.text' sections, you would write: + *(.text) + Here the `*' is a wildcard which matches any file name. To exclude +a list of files from matching the file name wildcard, EXCLUDE_FILE may +be used to match all files except the ones specified in the +EXCLUDE_FILE list. For example: + *(EXCLUDE_FILE (*crtend.o *otherfile.o) .ctors) + will cause all .ctors sections from all files except `crtend.o' and +`otherfile.o' to be included. + + There are two ways to include more than one section: + *(.text .rdata) + *(.text) *(.rdata) + The difference between these is the order in which the `.text' and +`.rdata' input sections will appear in the output section. In the +first example, they will be intermingled, appearing in the same order as +they are found in the linker input. In the second example, all `.text' +input sections will appear first, followed by all `.rdata' input +sections. + + You can specify a file name to include sections from a particular +file. You would do this if one or more of your files contain special +data that needs to be at a particular location in memory. For example: + data.o(.data) + + You can also specify files within archives by writing a pattern +matching the archive, a colon, then the pattern matching the file, with +no whitespace around the colon. + +`archive:file' + matches file within archive + +`archive:' + matches the whole archive + +`:file' + matches file but not one in an archive + + Either one or both of `archive' and `file' can contain shell +wildcards. On DOS based file systems, the linker will assume that a +single letter followed by a colon is a drive specifier, so `c:myfile.o' +is a simple file specification, not `myfile.o' within an archive called +`c'. `archive:file' filespecs may also be used within an +`EXCLUDE_FILE' list, but may not appear in other linker script +contexts. For instance, you cannot extract a file from an archive by +using `archive:file' in an `INPUT' command. + + If you use a file name without a list of sections, then all sections +in the input file will be included in the output section. This is not +commonly done, but it may by useful on occasion. For example: + data.o + + When you use a file name which is not an `archive:file' specifier +and does not contain any wild card characters, the linker will first +see if you also specified the file name on the linker command line or +in an `INPUT' command. If you did not, the linker will attempt to open +the file as an input file, as though it appeared on the command line. +Note that this differs from an `INPUT' command, because the linker will +not search for the file in the archive search path. + + +File: ld.info, Node: Input Section Wildcards, Next: Input Section Common, Prev: Input Section Basics, Up: Input Section + +3.6.4.2 Input Section Wildcard Patterns +....................................... + +In an input section description, either the file name or the section +name or both may be wildcard patterns. + + The file name of `*' seen in many examples is a simple wildcard +pattern for the file name. + + The wildcard patterns are like those used by the Unix shell. + +`*' + matches any number of characters + +`?' + matches any single character + +`[CHARS]' + matches a single instance of any of the CHARS; the `-' character + may be used to specify a range of characters, as in `[a-z]' to + match any lower case letter + +`\' + quotes the following character + + When a file name is matched with a wildcard, the wildcard characters +will not match a `/' character (used to separate directory names on +Unix). A pattern consisting of a single `*' character is an exception; +it will always match any file name, whether it contains a `/' or not. +In a section name, the wildcard characters will match a `/' character. + + File name wildcard patterns only match files which are explicitly +specified on the command line or in an `INPUT' command. The linker +does not search directories to expand wildcards. + + If a file name matches more than one wildcard pattern, or if a file +name appears explicitly and is also matched by a wildcard pattern, the +linker will use the first match in the linker script. For example, this +sequence of input section descriptions is probably in error, because the +`data.o' rule will not be used: + .data : { *(.data) } + .data1 : { data.o(.data) } + + Normally, the linker will place files and sections matched by +wildcards in the order in which they are seen during the link. You can +change this by using the `SORT_BY_NAME' keyword, which appears before a +wildcard pattern in parentheses (e.g., `SORT_BY_NAME(.text*)'). When +the `SORT_BY_NAME' keyword is used, the linker will sort the files or +sections into ascending order by name before placing them in the output +file. + + `SORT_BY_ALIGNMENT' is very similar to `SORT_BY_NAME'. The +difference is `SORT_BY_ALIGNMENT' will sort sections into ascending +order by alignment before placing them in the output file. + + `SORT' is an alias for `SORT_BY_NAME'. + + When there are nested section sorting commands in linker script, +there can be at most 1 level of nesting for section sorting commands. + + 1. `SORT_BY_NAME' (`SORT_BY_ALIGNMENT' (wildcard section pattern)). + It will sort the input sections by name first, then by alignment + if 2 sections have the same name. + + 2. `SORT_BY_ALIGNMENT' (`SORT_BY_NAME' (wildcard section pattern)). + It will sort the input sections by alignment first, then by name + if 2 sections have the same alignment. + + 3. `SORT_BY_NAME' (`SORT_BY_NAME' (wildcard section pattern)) is + treated the same as `SORT_BY_NAME' (wildcard section pattern). + + 4. `SORT_BY_ALIGNMENT' (`SORT_BY_ALIGNMENT' (wildcard section + pattern)) is treated the same as `SORT_BY_ALIGNMENT' (wildcard + section pattern). + + 5. All other nested section sorting commands are invalid. + + When both command line section sorting option and linker script +section sorting command are used, section sorting command always takes +precedence over the command line option. + + If the section sorting command in linker script isn't nested, the +command line option will make the section sorting command to be treated +as nested sorting command. + + 1. `SORT_BY_NAME' (wildcard section pattern ) with `--sort-sections + alignment' is equivalent to `SORT_BY_NAME' (`SORT_BY_ALIGNMENT' + (wildcard section pattern)). + + 2. `SORT_BY_ALIGNMENT' (wildcard section pattern) with + `--sort-section name' is equivalent to `SORT_BY_ALIGNMENT' + (`SORT_BY_NAME' (wildcard section pattern)). + + If the section sorting command in linker script is nested, the +command line option will be ignored. + + If you ever get confused about where input sections are going, use +the `-M' linker option to generate a map file. The map file shows +precisely how input sections are mapped to output sections. + + This example shows how wildcard patterns might be used to partition +files. This linker script directs the linker to place all `.text' +sections in `.text' and all `.bss' sections in `.bss'. The linker will +place the `.data' section from all files beginning with an upper case +character in `.DATA'; for all other files, the linker will place the +`.data' section in `.data'. + SECTIONS { + .text : { *(.text) } + .DATA : { [A-Z]*(.data) } + .data : { *(.data) } + .bss : { *(.bss) } + } + + +File: ld.info, Node: Input Section Common, Next: Input Section Keep, Prev: Input Section Wildcards, Up: Input Section + +3.6.4.3 Input Section for Common Symbols +........................................ + +A special notation is needed for common symbols, because in many object +file formats common symbols do not have a particular input section. The +linker treats common symbols as though they are in an input section +named `COMMON'. + + You may use file names with the `COMMON' section just as with any +other input sections. You can use this to place common symbols from a +particular input file in one section while common symbols from other +input files are placed in another section. + + In most cases, common symbols in input files will be placed in the +`.bss' section in the output file. For example: + .bss { *(.bss) *(COMMON) } + + Some object file formats have more than one type of common symbol. +For example, the MIPS ELF object file format distinguishes standard +common symbols and small common symbols. In this case, the linker will +use a different special section name for other types of common symbols. +In the case of MIPS ELF, the linker uses `COMMON' for standard common +symbols and `.scommon' for small common symbols. This permits you to +map the different types of common symbols into memory at different +locations. + + You will sometimes see `[COMMON]' in old linker scripts. This +notation is now considered obsolete. It is equivalent to `*(COMMON)'. + + +File: ld.info, Node: Input Section Keep, Next: Input Section Example, Prev: Input Section Common, Up: Input Section + +3.6.4.4 Input Section and Garbage Collection +............................................ + +When link-time garbage collection is in use (`--gc-sections'), it is +often useful to mark sections that should not be eliminated. This is +accomplished by surrounding an input section's wildcard entry with +`KEEP()', as in `KEEP(*(.init))' or `KEEP(SORT_BY_NAME(*)(.ctors))'. + + +File: ld.info, Node: Input Section Example, Prev: Input Section Keep, Up: Input Section + +3.6.4.5 Input Section Example +............................. + +The following example is a complete linker script. It tells the linker +to read all of the sections from file `all.o' and place them at the +start of output section `outputa' which starts at location `0x10000'. +All of section `.input1' from file `foo.o' follows immediately, in the +same output section. All of section `.input2' from `foo.o' goes into +output section `outputb', followed by section `.input1' from `foo1.o'. +All of the remaining `.input1' and `.input2' sections from any files +are written to output section `outputc'. + + SECTIONS { + outputa 0x10000 : + { + all.o + foo.o (.input1) + } + outputb : + { + foo.o (.input2) + foo1.o (.input1) + } + outputc : + { + *(.input1) + *(.input2) + } + } + + +File: ld.info, Node: Output Section Data, Next: Output Section Keywords, Prev: Input Section, Up: SECTIONS + +3.6.5 Output Section Data +------------------------- + +You can include explicit bytes of data in an output section by using +`BYTE', `SHORT', `LONG', `QUAD', or `SQUAD' as an output section +command. Each keyword is followed by an expression in parentheses +providing the value to store (*note Expressions::). The value of the +expression is stored at the current value of the location counter. + + The `BYTE', `SHORT', `LONG', and `QUAD' commands store one, two, +four, and eight bytes (respectively). After storing the bytes, the +location counter is incremented by the number of bytes stored. + + For example, this will store the byte 1 followed by the four byte +value of the symbol `addr': + BYTE(1) + LONG(addr) + + When using a 64 bit host or target, `QUAD' and `SQUAD' are the same; +they both store an 8 byte, or 64 bit, value. When both host and target +are 32 bits, an expression is computed as 32 bits. In this case `QUAD' +stores a 32 bit value zero extended to 64 bits, and `SQUAD' stores a 32 +bit value sign extended to 64 bits. + + If the object file format of the output file has an explicit +endianness, which is the normal case, the value will be stored in that +endianness. When the object file format does not have an explicit +endianness, as is true of, for example, S-records, the value will be +stored in the endianness of the first input object file. + + Note--these commands only work inside a section description and not +between them, so the following will produce an error from the linker: + SECTIONS { .text : { *(.text) } LONG(1) .data : { *(.data) } } + whereas this will work: + SECTIONS { .text : { *(.text) ; LONG(1) } .data : { *(.data) } } + + You may use the `FILL' command to set the fill pattern for the +current section. It is followed by an expression in parentheses. Any +otherwise unspecified regions of memory within the section (for example, +gaps left due to the required alignment of input sections) are filled +with the value of the expression, repeated as necessary. A `FILL' +statement covers memory locations after the point at which it occurs in +the section definition; by including more than one `FILL' statement, +you can have different fill patterns in different parts of an output +section. + + This example shows how to fill unspecified regions of memory with the +value `0x90': + FILL(0x90909090) + + The `FILL' command is similar to the `=FILLEXP' output section +attribute, but it only affects the part of the section following the +`FILL' command, rather than the entire section. If both are used, the +`FILL' command takes precedence. *Note Output Section Fill::, for +details on the fill expression. + + +File: ld.info, Node: Output Section Keywords, Next: Output Section Discarding, Prev: Output Section Data, Up: SECTIONS + +3.6.6 Output Section Keywords +----------------------------- + +There are a couple of keywords which can appear as output section +commands. + +`CREATE_OBJECT_SYMBOLS' + The command tells the linker to create a symbol for each input + file. The name of each symbol will be the name of the + corresponding input file. The section of each symbol will be the + output section in which the `CREATE_OBJECT_SYMBOLS' command + appears. + + This is conventional for the a.out object file format. It is not + normally used for any other object file format. + +`CONSTRUCTORS' + When linking using the a.out object file format, the linker uses an + unusual set construct to support C++ global constructors and + destructors. When linking object file formats which do not support + arbitrary sections, such as ECOFF and XCOFF, the linker will + automatically recognize C++ global constructors and destructors by + name. For these object file formats, the `CONSTRUCTORS' command + tells the linker to place constructor information in the output + section where the `CONSTRUCTORS' command appears. The + `CONSTRUCTORS' command is ignored for other object file formats. + + The symbol `__CTOR_LIST__' marks the start of the global + constructors, and the symbol `__CTOR_END__' marks the end. + Similarly, `__DTOR_LIST__' and `__DTOR_END__' mark the start and + end of the global destructors. The first word in the list is the + number of entries, followed by the address of each constructor or + destructor, followed by a zero word. The compiler must arrange to + actually run the code. For these object file formats GNU C++ + normally calls constructors from a subroutine `__main'; a call to + `__main' is automatically inserted into the startup code for + `main'. GNU C++ normally runs destructors either by using + `atexit', or directly from the function `exit'. + + For object file formats such as `COFF' or `ELF' which support + arbitrary section names, GNU C++ will normally arrange to put the + addresses of global constructors and destructors into the `.ctors' + and `.dtors' sections. Placing the following sequence into your + linker script will build the sort of table which the GNU C++ + runtime code expects to see. + + __CTOR_LIST__ = .; + LONG((__CTOR_END__ - __CTOR_LIST__) / 4 - 2) + *(.ctors) + LONG(0) + __CTOR_END__ = .; + __DTOR_LIST__ = .; + LONG((__DTOR_END__ - __DTOR_LIST__) / 4 - 2) + *(.dtors) + LONG(0) + __DTOR_END__ = .; + + If you are using the GNU C++ support for initialization priority, + which provides some control over the order in which global + constructors are run, you must sort the constructors at link time + to ensure that they are executed in the correct order. When using + the `CONSTRUCTORS' command, use `SORT_BY_NAME(CONSTRUCTORS)' + instead. When using the `.ctors' and `.dtors' sections, use + `*(SORT_BY_NAME(.ctors))' and `*(SORT_BY_NAME(.dtors))' instead of + just `*(.ctors)' and `*(.dtors)'. + + Normally the compiler and linker will handle these issues + automatically, and you will not need to concern yourself with + them. However, you may need to consider this if you are using C++ + and writing your own linker scripts. + + + +File: ld.info, Node: Output Section Discarding, Next: Output Section Attributes, Prev: Output Section Keywords, Up: SECTIONS + +3.6.7 Output Section Discarding +------------------------------- + +The linker will not create output sections with no contents. This is +for convenience when referring to input sections that may or may not be +present in any of the input files. For example: + .foo : { *(.foo) } + will only create a `.foo' section in the output file if there is a +`.foo' section in at least one input file, and if the input sections +are not all empty. Other link script directives that allocate space in +an output section will also create the output section. + + The linker will ignore address assignments (*note Output Section +Address::) on discarded output sections, except when the linker script +defines symbols in the output section. In that case the linker will +obey the address assignments, possibly advancing dot even though the +section is discarded. + + The special output section name `/DISCARD/' may be used to discard +input sections. Any input sections which are assigned to an output +section named `/DISCARD/' are not included in the output file. + + +File: ld.info, Node: Output Section Attributes, Next: Overlay Description, Prev: Output Section Discarding, Up: SECTIONS + +3.6.8 Output Section Attributes +------------------------------- + +We showed above that the full description of an output section looked +like this: + + SECTION [ADDRESS] [(TYPE)] : + [AT(LMA)] + [ALIGN(SECTION_ALIGN)] + [SUBALIGN(SUBSECTION_ALIGN)] + [CONSTRAINT] + { + OUTPUT-SECTION-COMMAND + OUTPUT-SECTION-COMMAND + ... + } [>REGION] [AT>LMA_REGION] [:PHDR :PHDR ...] [=FILLEXP] + + We've already described SECTION, ADDRESS, and +OUTPUT-SECTION-COMMAND. In this section we will describe the remaining +section attributes. + +* Menu: + +* Output Section Type:: Output section type +* Output Section LMA:: Output section LMA +* Forced Output Alignment:: Forced Output Alignment +* Forced Input Alignment:: Forced Input Alignment +* Output Section Constraint:: Output section constraint +* Output Section Region:: Output section region +* Output Section Phdr:: Output section phdr +* Output Section Fill:: Output section fill + + +File: ld.info, Node: Output Section Type, Next: Output Section LMA, Up: Output Section Attributes + +3.6.8.1 Output Section Type +........................... + +Each output section may have a type. The type is a keyword in +parentheses. The following types are defined: + +`NOLOAD' + The section should be marked as not loadable, so that it will not + be loaded into memory when the program is run. + +`DSECT' +`COPY' +`INFO' +`OVERLAY' + These type names are supported for backward compatibility, and are + rarely used. They all have the same effect: the section should be + marked as not allocatable, so that no memory is allocated for the + section when the program is run. + + The linker normally sets the attributes of an output section based on +the input sections which map into it. You can override this by using +the section type. For example, in the script sample below, the `ROM' +section is addressed at memory location `0' and does not need to be +loaded when the program is run. The contents of the `ROM' section will +appear in the linker output file as usual. + SECTIONS { + ROM 0 (NOLOAD) : { ... } + ... + } + + +File: ld.info, Node: Output Section LMA, Next: Forced Output Alignment, Prev: Output Section Type, Up: Output Section Attributes + +3.6.8.2 Output Section LMA +.......................... + +Every section has a virtual address (VMA) and a load address (LMA); see +*Note Basic Script Concepts::. The address expression which may appear +in an output section description sets the VMA (*note Output Section +Address::). + + The expression LMA that follows the `AT' keyword specifies the load +address of the section. + + Alternatively, with `AT>LMA_REGION' expression, you may specify a +memory region for the section's load address. *Note MEMORY::. Note +that if the section has not had a VMA assigned to it then the linker +will use the LMA_REGION as the VMA region as well. + + If neither `AT' nor `AT>' is specified for an allocatable section, +the linker will set the LMA such that the difference between VMA and +LMA for the section is the same as the preceding output section in the +same region. If there is no preceding output section or the section is +not allocatable, the linker will set the LMA equal to the VMA. *Note +Output Section Region::. + + This feature is designed to make it easy to build a ROM image. For +example, the following linker script creates three output sections: one +called `.text', which starts at `0x1000', one called `.mdata', which is +loaded at the end of the `.text' section even though its VMA is +`0x2000', and one called `.bss' to hold uninitialized data at address +`0x3000'. The symbol `_data' is defined with the value `0x2000', which +shows that the location counter holds the VMA value, not the LMA value. + + SECTIONS + { + .text 0x1000 : { *(.text) _etext = . ; } + .mdata 0x2000 : + AT ( ADDR (.text) + SIZEOF (.text) ) + { _data = . ; *(.data); _edata = . ; } + .bss 0x3000 : + { _bstart = . ; *(.bss) *(COMMON) ; _bend = . ;} + } + + The run-time initialization code for use with a program generated +with this linker script would include something like the following, to +copy the initialized data from the ROM image to its runtime address. +Notice how this code takes advantage of the symbols defined by the +linker script. + + extern char _etext, _data, _edata, _bstart, _bend; + char *src = &_etext; + char *dst = &_data; + + /* ROM has data at end of text; copy it. */ + while (dst < &_edata) { + *dst++ = *src++; + } + + /* Zero bss */ + for (dst = &_bstart; dst< &_bend; dst++) + *dst = 0; + + +File: ld.info, Node: Forced Output Alignment, Next: Forced Input Alignment, Prev: Output Section LMA, Up: Output Section Attributes + +3.6.8.3 Forced Output Alignment +............................... + +You can increase an output section's alignment by using ALIGN. + + +File: ld.info, Node: Forced Input Alignment, Next: Output Section Constraint, Prev: Forced Output Alignment, Up: Output Section Attributes + +3.6.8.4 Forced Input Alignment +.............................. + +You can force input section alignment within an output section by using +SUBALIGN. The value specified overrides any alignment given by input +sections, whether larger or smaller. + + +File: ld.info, Node: Output Section Constraint, Next: Output Section Region, Prev: Forced Input Alignment, Up: Output Section Attributes + +3.6.8.5 Output Section Constraint +................................. + +You can specify that an output section should only be created if all of +its input sections are read-only or all of its input sections are +read-write by using the keyword `ONLY_IF_RO' and `ONLY_IF_RW' +respectively. + + +File: ld.info, Node: Output Section Region, Next: Output Section Phdr, Prev: Output Section Constraint, Up: Output Section Attributes + +3.6.8.6 Output Section Region +............................. + +You can assign a section to a previously defined region of memory by +using `>REGION'. *Note MEMORY::. + + Here is a simple example: + MEMORY { rom : ORIGIN = 0x1000, LENGTH = 0x1000 } + SECTIONS { ROM : { *(.text) } >rom } + + +File: ld.info, Node: Output Section Phdr, Next: Output Section Fill, Prev: Output Section Region, Up: Output Section Attributes + +3.6.8.7 Output Section Phdr +........................... + +You can assign a section to a previously defined program segment by +using `:PHDR'. *Note PHDRS::. If a section is assigned to one or more +segments, then all subsequent allocated sections will be assigned to +those segments as well, unless they use an explicitly `:PHDR' modifier. +You can use `:NONE' to tell the linker to not put the section in any +segment at all. + + Here is a simple example: + PHDRS { text PT_LOAD ; } + SECTIONS { .text : { *(.text) } :text } + + +File: ld.info, Node: Output Section Fill, Prev: Output Section Phdr, Up: Output Section Attributes + +3.6.8.8 Output Section Fill +........................... + +You can set the fill pattern for an entire section by using `=FILLEXP'. +FILLEXP is an expression (*note Expressions::). Any otherwise +unspecified regions of memory within the output section (for example, +gaps left due to the required alignment of input sections) will be +filled with the value, repeated as necessary. If the fill expression +is a simple hex number, ie. a string of hex digit starting with `0x' +and without a trailing `k' or `M', then an arbitrarily long sequence of +hex digits can be used to specify the fill pattern; Leading zeros +become part of the pattern too. For all other cases, including extra +parentheses or a unary `+', the fill pattern is the four least +significant bytes of the value of the expression. In all cases, the +number is big-endian. + + You can also change the fill value with a `FILL' command in the +output section commands; (*note Output Section Data::). + + Here is a simple example: + SECTIONS { .text : { *(.text) } =0x90909090 } + + +File: ld.info, Node: Overlay Description, Prev: Output Section Attributes, Up: SECTIONS + +3.6.9 Overlay Description +------------------------- + +An overlay description provides an easy way to describe sections which +are to be loaded as part of a single memory image but are to be run at +the same memory address. At run time, some sort of overlay manager will +copy the overlaid sections in and out of the runtime memory address as +required, perhaps by simply manipulating addressing bits. This approach +can be useful, for example, when a certain region of memory is faster +than another. + + Overlays are described using the `OVERLAY' command. The `OVERLAY' +command is used within a `SECTIONS' command, like an output section +description. The full syntax of the `OVERLAY' command is as follows: + OVERLAY [START] : [NOCROSSREFS] [AT ( LDADDR )] + { + SECNAME1 + { + OUTPUT-SECTION-COMMAND + OUTPUT-SECTION-COMMAND + ... + } [:PHDR...] [=FILL] + SECNAME2 + { + OUTPUT-SECTION-COMMAND + OUTPUT-SECTION-COMMAND + ... + } [:PHDR...] [=FILL] + ... + } [>REGION] [:PHDR...] [=FILL] + + Everything is optional except `OVERLAY' (a keyword), and each +section must have a name (SECNAME1 and SECNAME2 above). The section +definitions within the `OVERLAY' construct are identical to those +within the general `SECTIONS' contruct (*note SECTIONS::), except that +no addresses and no memory regions may be defined for sections within +an `OVERLAY'. + + The sections are all defined with the same starting address. The +load addresses of the sections are arranged such that they are +consecutive in memory starting at the load address used for the +`OVERLAY' as a whole (as with normal section definitions, the load +address is optional, and defaults to the start address; the start +address is also optional, and defaults to the current value of the +location counter). + + If the `NOCROSSREFS' keyword is used, and there any references among +the sections, the linker will report an error. Since the sections all +run at the same address, it normally does not make sense for one +section to refer directly to another. *Note NOCROSSREFS: Miscellaneous +Commands. + + For each section within the `OVERLAY', the linker automatically +provides two symbols. The symbol `__load_start_SECNAME' is defined as +the starting load address of the section. The symbol +`__load_stop_SECNAME' is defined as the final load address of the +section. Any characters within SECNAME which are not legal within C +identifiers are removed. C (or assembler) code may use these symbols +to move the overlaid sections around as necessary. + + At the end of the overlay, the value of the location counter is set +to the start address of the overlay plus the size of the largest +section. + + Here is an example. Remember that this would appear inside a +`SECTIONS' construct. + OVERLAY 0x1000 : AT (0x4000) + { + .text0 { o1/*.o(.text) } + .text1 { o2/*.o(.text) } + } +This will define both `.text0' and `.text1' to start at address +0x1000. `.text0' will be loaded at address 0x4000, and `.text1' will +be loaded immediately after `.text0'. The following symbols will be +defined if referenced: `__load_start_text0', `__load_stop_text0', +`__load_start_text1', `__load_stop_text1'. + + C code to copy overlay `.text1' into the overlay area might look +like the following. + + extern char __load_start_text1, __load_stop_text1; + memcpy ((char *) 0x1000, &__load_start_text1, + &__load_stop_text1 - &__load_start_text1); + + Note that the `OVERLAY' command is just syntactic sugar, since +everything it does can be done using the more basic commands. The above +example could have been written identically as follows. + + .text0 0x1000 : AT (0x4000) { o1/*.o(.text) } + PROVIDE (__load_start_text0 = LOADADDR (.text0)); + PROVIDE (__load_stop_text0 = LOADADDR (.text0) + SIZEOF (.text0)); + .text1 0x1000 : AT (0x4000 + SIZEOF (.text0)) { o2/*.o(.text) } + PROVIDE (__load_start_text1 = LOADADDR (.text1)); + PROVIDE (__load_stop_text1 = LOADADDR (.text1) + SIZEOF (.text1)); + . = 0x1000 + MAX (SIZEOF (.text0), SIZEOF (.text1)); + + +File: ld.info, Node: MEMORY, Next: PHDRS, Prev: SECTIONS, Up: Scripts + +3.7 MEMORY Command +================== + +The linker's default configuration permits allocation of all available +memory. You can override this by using the `MEMORY' command. + + The `MEMORY' command describes the location and size of blocks of +memory in the target. You can use it to describe which memory regions +may be used by the linker, and which memory regions it must avoid. You +can then assign sections to particular memory regions. The linker will +set section addresses based on the memory regions, and will warn about +regions that become too full. The linker will not shuffle sections +around to fit into the available regions. + + A linker script may contain at most one use of the `MEMORY' command. +However, you can define as many blocks of memory within it as you +wish. The syntax is: + MEMORY + { + NAME [(ATTR)] : ORIGIN = ORIGIN, LENGTH = LEN + ... + } + + The NAME is a name used in the linker script to refer to the region. +The region name has no meaning outside of the linker script. Region +names are stored in a separate name space, and will not conflict with +symbol names, file names, or section names. Each memory region must +have a distinct name within the `MEMORY' command. However you can add +later alias names to existing memory regions with the *Note +REGION_ALIAS:: command. + + The ATTR string is an optional list of attributes that specify +whether to use a particular memory region for an input section which is +not explicitly mapped in the linker script. As described in *Note +SECTIONS::, if you do not specify an output section for some input +section, the linker will create an output section with the same name as +the input section. If you define region attributes, the linker will use +them to select the memory region for the output section that it creates. + + The ATTR string must consist only of the following characters: +`R' + Read-only section + +`W' + Read/write section + +`X' + Executable section + +`A' + Allocatable section + +`I' + Initialized section + +`L' + Same as `I' + +`!' + Invert the sense of any of the preceding attributes + + If a unmapped section matches any of the listed attributes other than +`!', it will be placed in the memory region. The `!' attribute +reverses this test, so that an unmapped section will be placed in the +memory region only if it does not match any of the listed attributes. + + The ORIGIN is an numerical expression for the start address of the +memory region. The expression must evaluate to a constant and it +cannot involve any symbols. The keyword `ORIGIN' may be abbreviated to +`org' or `o' (but not, for example, `ORG'). + + The LEN is an expression for the size in bytes of the memory region. +As with the ORIGIN expression, the expression must be numerical only +and must evaluate to a constant. The keyword `LENGTH' may be +abbreviated to `len' or `l'. + + In the following example, we specify that there are two memory +regions available for allocation: one starting at `0' for 256 kilobytes, +and the other starting at `0x40000000' for four megabytes. The linker +will place into the `rom' memory region every section which is not +explicitly mapped into a memory region, and is either read-only or +executable. The linker will place other sections which are not +explicitly mapped into a memory region into the `ram' memory region. + + MEMORY + { + rom (rx) : ORIGIN = 0, LENGTH = 256K + ram (!rx) : org = 0x40000000, l = 4M + } + + Once you define a memory region, you can direct the linker to place +specific output sections into that memory region by using the `>REGION' +output section attribute. For example, if you have a memory region +named `mem', you would use `>mem' in the output section definition. +*Note Output Section Region::. If no address was specified for the +output section, the linker will set the address to the next available +address within the memory region. If the combined output sections +directed to a memory region are too large for the region, the linker +will issue an error message. + + It is possible to access the origin and length of a memory in an +expression via the `ORIGIN(MEMORY)' and `LENGTH(MEMORY)' functions: + + _fstack = ORIGIN(ram) + LENGTH(ram) - 4; + + +File: ld.info, Node: PHDRS, Next: VERSION, Prev: MEMORY, Up: Scripts + +3.8 PHDRS Command +================= + +The ELF object file format uses "program headers", also knows as +"segments". The program headers describe how the program should be +loaded into memory. You can print them out by using the `objdump' +program with the `-p' option. + + When you run an ELF program on a native ELF system, the system loader +reads the program headers in order to figure out how to load the +program. This will only work if the program headers are set correctly. +This manual does not describe the details of how the system loader +interprets program headers; for more information, see the ELF ABI. + + The linker will create reasonable program headers by default. +However, in some cases, you may need to specify the program headers more +precisely. You may use the `PHDRS' command for this purpose. When the +linker sees the `PHDRS' command in the linker script, it will not +create any program headers other than the ones specified. + + The linker only pays attention to the `PHDRS' command when +generating an ELF output file. In other cases, the linker will simply +ignore `PHDRS'. + + This is the syntax of the `PHDRS' command. The words `PHDRS', +`FILEHDR', `AT', and `FLAGS' are keywords. + + PHDRS + { + NAME TYPE [ FILEHDR ] [ PHDRS ] [ AT ( ADDRESS ) ] + [ FLAGS ( FLAGS ) ] ; + } + + The NAME is used only for reference in the `SECTIONS' command of the +linker script. It is not put into the output file. Program header +names are stored in a separate name space, and will not conflict with +symbol names, file names, or section names. Each program header must +have a distinct name. + + Certain program header types describe segments of memory which the +system loader will load from the file. In the linker script, you +specify the contents of these segments by placing allocatable output +sections in the segments. You use the `:PHDR' output section attribute +to place a section in a particular segment. *Note Output Section +Phdr::. + + It is normal to put certain sections in more than one segment. This +merely implies that one segment of memory contains another. You may +repeat `:PHDR', using it once for each segment which should contain the +section. + + If you place a section in one or more segments using `:PHDR', then +the linker will place all subsequent allocatable sections which do not +specify `:PHDR' in the same segments. This is for convenience, since +generally a whole set of contiguous sections will be placed in a single +segment. You can use `:NONE' to override the default segment and tell +the linker to not put the section in any segment at all. + + You may use the `FILEHDR' and `PHDRS' keywords appear after the +program header type to further describe the contents of the segment. +The `FILEHDR' keyword means that the segment should include the ELF +file header. The `PHDRS' keyword means that the segment should include +the ELF program headers themselves. + + The TYPE may be one of the following. The numbers indicate the +value of the keyword. + +`PT_NULL' (0) + Indicates an unused program header. + +`PT_LOAD' (1) + Indicates that this program header describes a segment to be + loaded from the file. + +`PT_DYNAMIC' (2) + Indicates a segment where dynamic linking information can be found. + +`PT_INTERP' (3) + Indicates a segment where the name of the program interpreter may + be found. + +`PT_NOTE' (4) + Indicates a segment holding note information. + +`PT_SHLIB' (5) + A reserved program header type, defined but not specified by the + ELF ABI. + +`PT_PHDR' (6) + Indicates a segment where the program headers may be found. + +EXPRESSION + An expression giving the numeric type of the program header. This + may be used for types not defined above. + + You can specify that a segment should be loaded at a particular +address in memory by using an `AT' expression. This is identical to the +`AT' command used as an output section attribute (*note Output Section +LMA::). The `AT' command for a program header overrides the output +section attribute. + + The linker will normally set the segment flags based on the sections +which comprise the segment. You may use the `FLAGS' keyword to +explicitly specify the segment flags. The value of FLAGS must be an +integer. It is used to set the `p_flags' field of the program header. + + Here is an example of `PHDRS'. This shows a typical set of program +headers used on a native ELF system. + + PHDRS + { + headers PT_PHDR PHDRS ; + interp PT_INTERP ; + text PT_LOAD FILEHDR PHDRS ; + data PT_LOAD ; + dynamic PT_DYNAMIC ; + } + + SECTIONS + { + . = SIZEOF_HEADERS; + .interp : { *(.interp) } :text :interp + .text : { *(.text) } :text + .rodata : { *(.rodata) } /* defaults to :text */ + ... + . = . + 0x1000; /* move to a new page in memory */ + .data : { *(.data) } :data + .dynamic : { *(.dynamic) } :data :dynamic + ... + } + + +File: ld.info, Node: VERSION, Next: Expressions, Prev: PHDRS, Up: Scripts + +3.9 VERSION Command +=================== + +The linker supports symbol versions when using ELF. Symbol versions are +only useful when using shared libraries. The dynamic linker can use +symbol versions to select a specific version of a function when it runs +a program that may have been linked against an earlier version of the +shared library. + + You can include a version script directly in the main linker script, +or you can supply the version script as an implicit linker script. You +can also use the `--version-script' linker option. + + The syntax of the `VERSION' command is simply + VERSION { version-script-commands } + + The format of the version script commands is identical to that used +by Sun's linker in Solaris 2.5. The version script defines a tree of +version nodes. You specify the node names and interdependencies in the +version script. You can specify which symbols are bound to which +version nodes, and you can reduce a specified set of symbols to local +scope so that they are not globally visible outside of the shared +library. + + The easiest way to demonstrate the version script language is with a +few examples. + + VERS_1.1 { + global: + foo1; + local: + old*; + original*; + new*; + }; + + VERS_1.2 { + foo2; + } VERS_1.1; + + VERS_2.0 { + bar1; bar2; + extern "C++" { + ns::*; + "int f(int, double)"; + } + } VERS_1.2; + + This example version script defines three version nodes. The first +version node defined is `VERS_1.1'; it has no other dependencies. The +script binds the symbol `foo1' to `VERS_1.1'. It reduces a number of +symbols to local scope so that they are not visible outside of the +shared library; this is done using wildcard patterns, so that any +symbol whose name begins with `old', `original', or `new' is matched. +The wildcard patterns available are the same as those used in the shell +when matching filenames (also known as "globbing"). However, if you +specify the symbol name inside double quotes, then the name is treated +as literal, rather than as a glob pattern. + + Next, the version script defines node `VERS_1.2'. This node depends +upon `VERS_1.1'. The script binds the symbol `foo2' to the version +node `VERS_1.2'. + + Finally, the version script defines node `VERS_2.0'. This node +depends upon `VERS_1.2'. The scripts binds the symbols `bar1' and +`bar2' are bound to the version node `VERS_2.0'. + + When the linker finds a symbol defined in a library which is not +specifically bound to a version node, it will effectively bind it to an +unspecified base version of the library. You can bind all otherwise +unspecified symbols to a given version node by using `global: *;' +somewhere in the version script. Note that it's slightly crazy to use +wildcards in a global spec except on the last version node. Global +wildcards elsewhere run the risk of accidentally adding symbols to the +set exported for an old version. That's wrong since older versions +ought to have a fixed set of symbols. + + The names of the version nodes have no specific meaning other than +what they might suggest to the person reading them. The `2.0' version +could just as well have appeared in between `1.1' and `1.2'. However, +this would be a confusing way to write a version script. + + Node name can be omitted, provided it is the only version node in +the version script. Such version script doesn't assign any versions to +symbols, only selects which symbols will be globally visible out and +which won't. + + { global: foo; bar; local: *; }; + + When you link an application against a shared library that has +versioned symbols, the application itself knows which version of each +symbol it requires, and it also knows which version nodes it needs from +each shared library it is linked against. Thus at runtime, the dynamic +loader can make a quick check to make sure that the libraries you have +linked against do in fact supply all of the version nodes that the +application will need to resolve all of the dynamic symbols. In this +way it is possible for the dynamic linker to know with certainty that +all external symbols that it needs will be resolvable without having to +search for each symbol reference. + + The symbol versioning is in effect a much more sophisticated way of +doing minor version checking that SunOS does. The fundamental problem +that is being addressed here is that typically references to external +functions are bound on an as-needed basis, and are not all bound when +the application starts up. If a shared library is out of date, a +required interface may be missing; when the application tries to use +that interface, it may suddenly and unexpectedly fail. With symbol +versioning, the user will get a warning when they start their program if +the libraries being used with the application are too old. + + There are several GNU extensions to Sun's versioning approach. The +first of these is the ability to bind a symbol to a version node in the +source file where the symbol is defined instead of in the versioning +script. This was done mainly to reduce the burden on the library +maintainer. You can do this by putting something like: + __asm__(".symver original_foo,foo@VERS_1.1"); + in the C source file. This renames the function `original_foo' to +be an alias for `foo' bound to the version node `VERS_1.1'. The +`local:' directive can be used to prevent the symbol `original_foo' +from being exported. A `.symver' directive takes precedence over a +version script. + + The second GNU extension is to allow multiple versions of the same +function to appear in a given shared library. In this way you can make +an incompatible change to an interface without increasing the major +version number of the shared library, while still allowing applications +linked against the old interface to continue to function. + + To do this, you must use multiple `.symver' directives in the source +file. Here is an example: + + __asm__(".symver original_foo,foo@"); + __asm__(".symver old_foo,foo@VERS_1.1"); + __asm__(".symver old_foo1,foo@VERS_1.2"); + __asm__(".symver new_foo,foo@@VERS_2.0"); + + In this example, `foo@' represents the symbol `foo' bound to the +unspecified base version of the symbol. The source file that contains +this example would define 4 C functions: `original_foo', `old_foo', +`old_foo1', and `new_foo'. + + When you have multiple definitions of a given symbol, there needs to +be some way to specify a default version to which external references to +this symbol will be bound. You can do this with the `foo@@VERS_2.0' +type of `.symver' directive. You can only declare one version of a +symbol as the default in this manner; otherwise you would effectively +have multiple definitions of the same symbol. + + If you wish to bind a reference to a specific version of the symbol +within the shared library, you can use the aliases of convenience +(i.e., `old_foo'), or you can use the `.symver' directive to +specifically bind to an external version of the function in question. + + You can also specify the language in the version script: + + VERSION extern "lang" { version-script-commands } + + The supported `lang's are `C', `C++', and `Java'. The linker will +iterate over the list of symbols at the link time and demangle them +according to `lang' before matching them to the patterns specified in +`version-script-commands'. + + Demangled names may contains spaces and other special characters. As +described above, you can use a glob pattern to match demangled names, +or you can use a double-quoted string to match the string exactly. In +the latter case, be aware that minor differences (such as differing +whitespace) between the version script and the demangler output will +cause a mismatch. As the exact string generated by the demangler might +change in the future, even if the mangled name does not, you should +check that all of your version directives are behaving as you expect +when you upgrade. + + +File: ld.info, Node: Expressions, Next: Implicit Linker Scripts, Prev: VERSION, Up: Scripts + +3.10 Expressions in Linker Scripts +================================== + +The syntax for expressions in the linker script language is identical to +that of C expressions. All expressions are evaluated as integers. All +expressions are evaluated in the same size, which is 32 bits if both the +host and target are 32 bits, and is otherwise 64 bits. + + You can use and set symbol values in expressions. + + The linker defines several special purpose builtin functions for use +in expressions. + +* Menu: + +* Constants:: Constants +* Symbolic Constants:: Symbolic constants +* Symbols:: Symbol Names +* Orphan Sections:: Orphan Sections +* Location Counter:: The Location Counter +* Operators:: Operators +* Evaluation:: Evaluation +* Expression Section:: The Section of an Expression +* Builtin Functions:: Builtin Functions + + +File: ld.info, Node: Constants, Next: Symbolic Constants, Up: Expressions + +3.10.1 Constants +---------------- + +All constants are integers. + + As in C, the linker considers an integer beginning with `0' to be +octal, and an integer beginning with `0x' or `0X' to be hexadecimal. +Alternatively the linker accepts suffixes of `h' or `H' for +hexadeciaml, `o' or `O' for octal, `b' or `B' for binary and `d' or `D' +for decimal. Any integer value without a prefix or a suffix is +considered to be decimal. + + In addition, you can use the suffixes `K' and `M' to scale a +constant by `1024' or `1024*1024' respectively. For example, the +following all refer to the same quantity: + + _fourk_1 = 4K; + _fourk_2 = 4096; + _fourk_3 = 0x1000; + _fourk_4 = 10000o; + + Note - the `K' and `M' suffixes cannot be used in conjunction with +the base suffixes mentioned above. + + +File: ld.info, Node: Symbolic Constants, Next: Symbols, Prev: Constants, Up: Expressions + +3.10.2 Symbolic Constants +------------------------- + +It is possible to refer to target specific constants via the use of the +`CONSTANT(NAME)' operator, where NAME is one of: + +`MAXPAGESIZE' + The target's maximum page size. + +`COMMONPAGESIZE' + The target's default page size. + + So for example: + + .text ALIGN (CONSTANT (MAXPAGESIZE)) : { *(.text) } + + will create a text section aligned to the largest page boundary +supported by the target. + + +File: ld.info, Node: Symbols, Next: Orphan Sections, Prev: Symbolic Constants, Up: Expressions + +3.10.3 Symbol Names +------------------- + +Unless quoted, symbol names start with a letter, underscore, or period +and may include letters, digits, underscores, periods, and hyphens. +Unquoted symbol names must not conflict with any keywords. You can +specify a symbol which contains odd characters or has the same name as a +keyword by surrounding the symbol name in double quotes: + "SECTION" = 9; + "with a space" = "also with a space" + 10; + + Since symbols can contain many non-alphabetic characters, it is +safest to delimit symbols with spaces. For example, `A-B' is one +symbol, whereas `A - B' is an expression involving subtraction. + + +File: ld.info, Node: Orphan Sections, Next: Location Counter, Prev: Symbols, Up: Expressions + +3.10.4 Orphan Sections +---------------------- + +Orphan sections are sections present in the input files which are not +explicitly placed into the output file by the linker script. The +linker will still copy these sections into the output file, but it has +to guess as to where they should be placed. The linker uses a simple +heuristic to do this. It attempts to place orphan sections after +non-orphan sections of the same attribute, such as code vs data, +loadable vs non-loadable, etc. If there is not enough room to do this +then it places at the end of the file. + + For ELF targets, the attribute of the section includes section type +as well as section flag. + + If an orphaned section's name is representable as a C identifier then +the linker will automatically *note PROVIDE:: two symbols: +__start_SECNAME and __end_SECNAME, where SECNAME is the name of the +section. These indicate the start address and end address of the +orphaned section respectively. Note: most section names are not +representable as C identifiers because they contain a `.' character. + + +File: ld.info, Node: Location Counter, Next: Operators, Prev: Orphan Sections, Up: Expressions + +3.10.5 The Location Counter +--------------------------- + +The special linker variable "dot" `.' always contains the current +output location counter. Since the `.' always refers to a location in +an output section, it may only appear in an expression within a +`SECTIONS' command. The `.' symbol may appear anywhere that an +ordinary symbol is allowed in an expression. + + Assigning a value to `.' will cause the location counter to be +moved. This may be used to create holes in the output section. The +location counter may not be moved backwards inside an output section, +and may not be moved backwards outside of an output section if so doing +creates areas with overlapping LMAs. + + SECTIONS + { + output : + { + file1(.text) + . = . + 1000; + file2(.text) + . += 1000; + file3(.text) + } = 0x12345678; + } + In the previous example, the `.text' section from `file1' is located +at the beginning of the output section `output'. It is followed by a +1000 byte gap. Then the `.text' section from `file2' appears, also +with a 1000 byte gap following before the `.text' section from `file3'. +The notation `= 0x12345678' specifies what data to write in the gaps +(*note Output Section Fill::). + + Note: `.' actually refers to the byte offset from the start of the +current containing object. Normally this is the `SECTIONS' statement, +whose start address is 0, hence `.' can be used as an absolute address. +If `.' is used inside a section description however, it refers to the +byte offset from the start of that section, not an absolute address. +Thus in a script like this: + + SECTIONS + { + . = 0x100 + .text: { + *(.text) + . = 0x200 + } + . = 0x500 + .data: { + *(.data) + . += 0x600 + } + } + + The `.text' section will be assigned a starting address of 0x100 and +a size of exactly 0x200 bytes, even if there is not enough data in the +`.text' input sections to fill this area. (If there is too much data, +an error will be produced because this would be an attempt to move `.' +backwards). The `.data' section will start at 0x500 and it will have +an extra 0x600 bytes worth of space after the end of the values from +the `.data' input sections and before the end of the `.data' output +section itself. + + Setting symbols to the value of the location counter outside of an +output section statement can result in unexpected values if the linker +needs to place orphan sections. For example, given the following: + + SECTIONS + { + start_of_text = . ; + .text: { *(.text) } + end_of_text = . ; + + start_of_data = . ; + .data: { *(.data) } + end_of_data = . ; + } + + If the linker needs to place some input section, e.g. `.rodata', not +mentioned in the script, it might choose to place that section between +`.text' and `.data'. You might think the linker should place `.rodata' +on the blank line in the above script, but blank lines are of no +particular significance to the linker. As well, the linker doesn't +associate the above symbol names with their sections. Instead, it +assumes that all assignments or other statements belong to the previous +output section, except for the special case of an assignment to `.'. +I.e., the linker will place the orphan `.rodata' section as if the +script was written as follows: + + SECTIONS + { + start_of_text = . ; + .text: { *(.text) } + end_of_text = . ; + + start_of_data = . ; + .rodata: { *(.rodata) } + .data: { *(.data) } + end_of_data = . ; + } + + This may or may not be the script author's intention for the value of +`start_of_data'. One way to influence the orphan section placement is +to assign the location counter to itself, as the linker assumes that an +assignment to `.' is setting the start address of a following output +section and thus should be grouped with that section. So you could +write: + + SECTIONS + { + start_of_text = . ; + .text: { *(.text) } + end_of_text = . ; + + . = . ; + start_of_data = . ; + .data: { *(.data) } + end_of_data = . ; + } + + Now, the orphan `.rodata' section will be placed between +`end_of_text' and `start_of_data'. + + +File: ld.info, Node: Operators, Next: Evaluation, Prev: Location Counter, Up: Expressions + +3.10.6 Operators +---------------- + +The linker recognizes the standard C set of arithmetic operators, with +the standard bindings and precedence levels: + precedence associativity Operators Notes + (highest) + 1 left ! - ~ (1) + 2 left * / % + 3 left + - + 4 left >> << + 5 left == != > < <= >= + 6 left & + 7 left | + 8 left && + 9 left || + 10 right ? : + 11 right &= += -= *= /= (2) + (lowest) + Notes: (1) Prefix operators (2) *Note Assignments::. + + +File: ld.info, Node: Evaluation, Next: Expression Section, Prev: Operators, Up: Expressions + +3.10.7 Evaluation +----------------- + +The linker evaluates expressions lazily. It only computes the value of +an expression when absolutely necessary. + + The linker needs some information, such as the value of the start +address of the first section, and the origins and lengths of memory +regions, in order to do any linking at all. These values are computed +as soon as possible when the linker reads in the linker script. + + However, other values (such as symbol values) are not known or needed +until after storage allocation. Such values are evaluated later, when +other information (such as the sizes of output sections) is available +for use in the symbol assignment expression. + + The sizes of sections cannot be known until after allocation, so +assignments dependent upon these are not performed until after +allocation. + + Some expressions, such as those depending upon the location counter +`.', must be evaluated during section allocation. + + If the result of an expression is required, but the value is not +available, then an error results. For example, a script like the +following + SECTIONS + { + .text 9+this_isnt_constant : + { *(.text) } + } +will cause the error message `non constant expression for initial +address'. + + +File: ld.info, Node: Expression Section, Next: Builtin Functions, Prev: Evaluation, Up: Expressions + +3.10.8 The Section of an Expression +----------------------------------- + +When the linker evaluates an expression, the result is either absolute +or relative to some section. A relative expression is expressed as a +fixed offset from the base of a section. + + The position of the expression within the linker script determines +whether it is absolute or relative. An expression which appears within +an output section definition is relative to the base of the output +section. An expression which appears elsewhere will be absolute. + + A symbol set to a relative expression will be relocatable if you +request relocatable output using the `-r' option. That means that a +further link operation may change the value of the symbol. The symbol's +section will be the section of the relative expression. + + A symbol set to an absolute expression will retain the same value +through any further link operation. The symbol will be absolute, and +will not have any particular associated section. + + You can use the builtin function `ABSOLUTE' to force an expression +to be absolute when it would otherwise be relative. For example, to +create an absolute symbol set to the address of the end of the output +section `.data': + SECTIONS + { + .data : { *(.data) _edata = ABSOLUTE(.); } + } + If `ABSOLUTE' were not used, `_edata' would be relative to the +`.data' section. + + +File: ld.info, Node: Builtin Functions, Prev: Expression Section, Up: Expressions + +3.10.9 Builtin Functions +------------------------ + +The linker script language includes a number of builtin functions for +use in linker script expressions. + +`ABSOLUTE(EXP)' + Return the absolute (non-relocatable, as opposed to non-negative) + value of the expression EXP. Primarily useful to assign an + absolute value to a symbol within a section definition, where + symbol values are normally section relative. *Note Expression + Section::. + +`ADDR(SECTION)' + Return the absolute address (the VMA) of the named SECTION. Your + script must previously have defined the location of that section. + In the following example, `symbol_1' and `symbol_2' are assigned + identical values: + SECTIONS { ... + .output1 : + { + start_of_output_1 = ABSOLUTE(.); + ... + } + .output : + { + symbol_1 = ADDR(.output1); + symbol_2 = start_of_output_1; + } + ... } + +`ALIGN(ALIGN)' +`ALIGN(EXP,ALIGN)' + Return the location counter (`.') or arbitrary expression aligned + to the next ALIGN boundary. The single operand `ALIGN' doesn't + change the value of the location counter--it just does arithmetic + on it. The two operand `ALIGN' allows an arbitrary expression to + be aligned upwards (`ALIGN(ALIGN)' is equivalent to `ALIGN(., + ALIGN)'). + + Here is an example which aligns the output `.data' section to the + next `0x2000' byte boundary after the preceding section and sets a + variable within the section to the next `0x8000' boundary after the + input sections: + SECTIONS { ... + .data ALIGN(0x2000): { + *(.data) + variable = ALIGN(0x8000); + } + ... } + The first use of `ALIGN' in this example specifies the + location of a section because it is used as the optional ADDRESS + attribute of a section definition (*note Output Section + Address::). The second use of `ALIGN' is used to defines the + value of a symbol. + + The builtin function `NEXT' is closely related to `ALIGN'. + +`ALIGNOF(SECTION)' + Return the alignment in bytes of the named SECTION, if that + section has been allocated. If the section has not been allocated + when this is evaluated, the linker will report an error. In the + following example, the alignment of the `.output' section is + stored as the first value in that section. + SECTIONS{ ... + .output { + LONG (ALIGNOF (.output)) + ... + } + ... } + +`BLOCK(EXP)' + This is a synonym for `ALIGN', for compatibility with older linker + scripts. It is most often seen when setting the address of an + output section. + +`DATA_SEGMENT_ALIGN(MAXPAGESIZE, COMMONPAGESIZE)' + This is equivalent to either + (ALIGN(MAXPAGESIZE) + (. & (MAXPAGESIZE - 1))) + or + (ALIGN(MAXPAGESIZE) + (. & (MAXPAGESIZE - COMMONPAGESIZE))) + depending on whether the latter uses fewer COMMONPAGESIZE sized + pages for the data segment (area between the result of this + expression and `DATA_SEGMENT_END') than the former or not. If the + latter form is used, it means COMMONPAGESIZE bytes of runtime + memory will be saved at the expense of up to COMMONPAGESIZE wasted + bytes in the on-disk file. + + This expression can only be used directly in `SECTIONS' commands, + not in any output section descriptions and only once in the linker + script. COMMONPAGESIZE should be less or equal to MAXPAGESIZE and + should be the system page size the object wants to be optimized + for (while still working on system page sizes up to MAXPAGESIZE). + + Example: + . = DATA_SEGMENT_ALIGN(0x10000, 0x2000); + +`DATA_SEGMENT_END(EXP)' + This defines the end of data segment for `DATA_SEGMENT_ALIGN' + evaluation purposes. + + . = DATA_SEGMENT_END(.); + +`DATA_SEGMENT_RELRO_END(OFFSET, EXP)' + This defines the end of the `PT_GNU_RELRO' segment when `-z relro' + option is used. Second argument is returned. When `-z relro' + option is not present, `DATA_SEGMENT_RELRO_END' does nothing, + otherwise `DATA_SEGMENT_ALIGN' is padded so that EXP + OFFSET is + aligned to the most commonly used page boundary for particular + target. If present in the linker script, it must always come in + between `DATA_SEGMENT_ALIGN' and `DATA_SEGMENT_END'. + + . = DATA_SEGMENT_RELRO_END(24, .); + +`DEFINED(SYMBOL)' + Return 1 if SYMBOL is in the linker global symbol table and is + defined before the statement using DEFINED in the script, otherwise + return 0. You can use this function to provide default values for + symbols. For example, the following script fragment shows how to + set a global symbol `begin' to the first location in the `.text' + section--but if a symbol called `begin' already existed, its value + is preserved: + + SECTIONS { ... + .text : { + begin = DEFINED(begin) ? begin : . ; + ... + } + ... + } + +`LENGTH(MEMORY)' + Return the length of the memory region named MEMORY. + +`LOADADDR(SECTION)' + Return the absolute LMA of the named SECTION. This is normally + the same as `ADDR', but it may be different if the `AT' attribute + is used in the output section definition (*note Output Section + LMA::). + +`MAX(EXP1, EXP2)' + Returns the maximum of EXP1 and EXP2. + +`MIN(EXP1, EXP2)' + Returns the minimum of EXP1 and EXP2. + +`NEXT(EXP)' + Return the next unallocated address that is a multiple of EXP. + This function is closely related to `ALIGN(EXP)'; unless you use + the `MEMORY' command to define discontinuous memory for the output + file, the two functions are equivalent. + +`ORIGIN(MEMORY)' + Return the origin of the memory region named MEMORY. + +`SEGMENT_START(SEGMENT, DEFAULT)' + Return the base address of the named SEGMENT. If an explicit + value has been given for this segment (with a command-line `-T' + option) that value will be returned; otherwise the value will be + DEFAULT. At present, the `-T' command-line option can only be + used to set the base address for the "text", "data", and "bss" + sections, but you use `SEGMENT_START' with any segment name. + +`SIZEOF(SECTION)' + Return the size in bytes of the named SECTION, if that section has + been allocated. If the section has not been allocated when this is + evaluated, the linker will report an error. In the following + example, `symbol_1' and `symbol_2' are assigned identical values: + SECTIONS{ ... + .output { + .start = . ; + ... + .end = . ; + } + symbol_1 = .end - .start ; + symbol_2 = SIZEOF(.output); + ... } + +`SIZEOF_HEADERS' +`sizeof_headers' + Return the size in bytes of the output file's headers. This is + information which appears at the start of the output file. You + can use this number when setting the start address of the first + section, if you choose, to facilitate paging. + + When producing an ELF output file, if the linker script uses the + `SIZEOF_HEADERS' builtin function, the linker must compute the + number of program headers before it has determined all the section + addresses and sizes. If the linker later discovers that it needs + additional program headers, it will report an error `not enough + room for program headers'. To avoid this error, you must avoid + using the `SIZEOF_HEADERS' function, or you must rework your linker + script to avoid forcing the linker to use additional program + headers, or you must define the program headers yourself using the + `PHDRS' command (*note PHDRS::). + + +File: ld.info, Node: Implicit Linker Scripts, Prev: Expressions, Up: Scripts + +3.11 Implicit Linker Scripts +============================ + +If you specify a linker input file which the linker can not recognize as +an object file or an archive file, it will try to read the file as a +linker script. If the file can not be parsed as a linker script, the +linker will report an error. + + An implicit linker script will not replace the default linker script. + + Typically an implicit linker script would contain only symbol +assignments, or the `INPUT', `GROUP', or `VERSION' commands. + + Any input files read because of an implicit linker script will be +read at the position in the command line where the implicit linker +script was read. This can affect archive searching. + + +File: ld.info, Node: Machine Dependent, Next: BFD, Prev: Scripts, Up: Top + +4 Machine Dependent Features +**************************** + +`ld' has additional features on some platforms; the following sections +describe them. Machines where `ld' has no additional functionality are +not listed. + +* Menu: + + +* H8/300:: `ld' and the H8/300 + +* i960:: `ld' and the Intel 960 family + +* ARM:: `ld' and the ARM family + +* HPPA ELF32:: `ld' and HPPA 32-bit ELF + +* M68K:: `ld' and the Motorola 68K family + +* MMIX:: `ld' and MMIX + +* MSP430:: `ld' and MSP430 + +* M68HC11/68HC12:: `ld' and the Motorola 68HC11 and 68HC12 families + +* PowerPC ELF32:: `ld' and PowerPC 32-bit ELF Support + +* PowerPC64 ELF64:: `ld' and PowerPC64 64-bit ELF Support + +* SPU ELF:: `ld' and SPU ELF Support + +* TI COFF:: `ld' and TI COFF + +* WIN32:: `ld' and WIN32 (cygwin/mingw) + +* Xtensa:: `ld' and Xtensa Processors + + +File: ld.info, Node: H8/300, Next: i960, Up: Machine Dependent + +4.1 `ld' and the H8/300 +======================= + +For the H8/300, `ld' can perform these global optimizations when you +specify the `--relax' command-line option. + +_relaxing address modes_ + `ld' finds all `jsr' and `jmp' instructions whose targets are + within eight bits, and turns them into eight-bit program-counter + relative `bsr' and `bra' instructions, respectively. + +_synthesizing instructions_ + `ld' finds all `mov.b' instructions which use the sixteen-bit + absolute address form, but refer to the top page of memory, and + changes them to use the eight-bit address form. (That is: the + linker turns `mov.b `@'AA:16' into `mov.b `@'AA:8' whenever the + address AA is in the top page of memory). + +_bit manipulation instructions_ + `ld' finds all bit manipulation instructions like `band, bclr, + biand, bild, bior, bist, bixor, bld, bnot, bor, bset, bst, btst, + bxor' which use 32 bit and 16 bit absolute address form, but refer + to the top page of memory, and changes them to use the 8 bit + address form. (That is: the linker turns `bset #xx:3,`@'AA:32' + into `bset #xx:3,`@'AA:8' whenever the address AA is in the top + page of memory). + +_system control instructions_ + `ld' finds all `ldc.w, stc.w' instructions which use the 32 bit + absolute address form, but refer to the top page of memory, and + changes them to use 16 bit address form. (That is: the linker + turns `ldc.w `@'AA:32,ccr' into `ldc.w `@'AA:16,ccr' whenever the + address AA is in the top page of memory). + + +File: ld.info, Node: i960, Next: ARM, Prev: H8/300, Up: Machine Dependent + +4.2 `ld' and the Intel 960 Family +================================= + +You can use the `-AARCHITECTURE' command line option to specify one of +the two-letter names identifying members of the 960 family; the option +specifies the desired output target, and warns of any incompatible +instructions in the input files. It also modifies the linker's search +strategy for archive libraries, to support the use of libraries +specific to each particular architecture, by including in the search +loop names suffixed with the string identifying the architecture. + + For example, if your `ld' command line included `-ACA' as well as +`-ltry', the linker would look (in its built-in search paths, and in +any paths you specify with `-L') for a library with the names + + try + libtry.a + tryca + libtryca.a + +The first two possibilities would be considered in any event; the last +two are due to the use of `-ACA'. + + You can meaningfully use `-A' more than once on a command line, since +the 960 architecture family allows combination of target architectures; +each use will add another pair of name variants to search for when `-l' +specifies a library. + + `ld' supports the `--relax' option for the i960 family. If you +specify `--relax', `ld' finds all `balx' and `calx' instructions whose +targets are within 24 bits, and turns them into 24-bit program-counter +relative `bal' and `cal' instructions, respectively. `ld' also turns +`cal' instructions into `bal' instructions when it determines that the +target subroutine is a leaf routine (that is, the target subroutine does +not itself call any subroutines). + + The `--fix-cortex-a8' switch enables a link-time workaround for an +erratum in certain Cortex-A8 processors. The workaround is enabled by +default if you are targeting the ARM v7-A architecture profile. It can +be enabled otherwise by specifying `--fix-cortex-a8', or disabled +unconditionally by specifying `--no-fix-cortex-a8'. + + The erratum only affects Thumb-2 code. Please contact ARM for +further details. + + +File: ld.info, Node: M68HC11/68HC12, Next: PowerPC ELF32, Prev: MSP430, Up: Machine Dependent + +4.3 `ld' and the Motorola 68HC11 and 68HC12 families +==================================================== + +4.3.1 Linker Relaxation +----------------------- + +For the Motorola 68HC11, `ld' can perform these global optimizations +when you specify the `--relax' command-line option. + +_relaxing address modes_ + `ld' finds all `jsr' and `jmp' instructions whose targets are + within eight bits, and turns them into eight-bit program-counter + relative `bsr' and `bra' instructions, respectively. + + `ld' also looks at all 16-bit extended addressing modes and + transforms them in a direct addressing mode when the address is in + page 0 (between 0 and 0x0ff). + +_relaxing gcc instruction group_ + When `gcc' is called with `-mrelax', it can emit group of + instructions that the linker can optimize to use a 68HC11 direct + addressing mode. These instructions consists of `bclr' or `bset' + instructions. + + +4.3.2 Trampoline Generation +--------------------------- + +For 68HC11 and 68HC12, `ld' can generate trampoline code to call a far +function using a normal `jsr' instruction. The linker will also change +the relocation to some far function to use the trampoline address +instead of the function address. This is typically the case when a +pointer to a function is taken. The pointer will in fact point to the +function trampoline. + + +File: ld.info, Node: ARM, Next: HPPA ELF32, Prev: i960, Up: Machine Dependent + +4.4 `ld' and the ARM family +=========================== + +For the ARM, `ld' will generate code stubs to allow functions calls +between ARM and Thumb code. These stubs only work with code that has +been compiled and assembled with the `-mthumb-interwork' command line +option. If it is necessary to link with old ARM object files or +libraries, which have not been compiled with the -mthumb-interwork +option then the `--support-old-code' command line switch should be +given to the linker. This will make it generate larger stub functions +which will work with non-interworking aware ARM code. Note, however, +the linker does not support generating stubs for function calls to +non-interworking aware Thumb code. + + The `--thumb-entry' switch is a duplicate of the generic `--entry' +switch, in that it sets the program's starting address. But it also +sets the bottom bit of the address, so that it can be branched to using +a BX instruction, and the program will start executing in Thumb mode +straight away. + + The `--use-nul-prefixed-import-tables' switch is specifying, that +the import tables idata4 and idata5 have to be generated with a zero +elememt prefix for import libraries. This is the old style to generate +import tables. By default this option is turned off. + + The `--be8' switch instructs `ld' to generate BE8 format +executables. This option is only valid when linking big-endian objects. +The resulting image will contain big-endian data and little-endian code. + + The `R_ARM_TARGET1' relocation is typically used for entries in the +`.init_array' section. It is interpreted as either `R_ARM_REL32' or +`R_ARM_ABS32', depending on the target. The `--target1-rel' and +`--target1-abs' switches override the default. + + The `--target2=type' switch overrides the default definition of the +`R_ARM_TARGET2' relocation. Valid values for `type', their meanings, +and target defaults are as follows: +`rel' + `R_ARM_REL32' (arm*-*-elf, arm*-*-eabi) + +`abs' + `R_ARM_ABS32' (arm*-*-symbianelf) + +`got-rel' + `R_ARM_GOT_PREL' (arm*-*-linux, arm*-*-*bsd) + + The `R_ARM_V4BX' relocation (defined by the ARM AAELF specification) +enables objects compiled for the ARMv4 architecture to be +interworking-safe when linked with other objects compiled for ARMv4t, +but also allows pure ARMv4 binaries to be built from the same ARMv4 +objects. + + In the latter case, the switch `--fix-v4bx' must be passed to the +linker, which causes v4t `BX rM' instructions to be rewritten as `MOV +PC,rM', since v4 processors do not have a `BX' instruction. + + In the former case, the switch should not be used, and `R_ARM_V4BX' +relocations are ignored. + + Replace `BX rM' instructions identified by `R_ARM_V4BX' relocations +with a branch to the following veneer: + + TST rM, #1 + MOVEQ PC, rM + BX Rn + + This allows generation of libraries/applications that work on ARMv4 +cores and are still interworking safe. Note that the above veneer +clobbers the condition flags, so may cause incorrect progrm behavior in +rare cases. + + The `--use-blx' switch enables the linker to use ARM/Thumb BLX +instructions (available on ARMv5t and above) in various situations. +Currently it is used to perform calls via the PLT from Thumb code using +BLX rather than using BX and a mode-switching stub before each PLT +entry. This should lead to such calls executing slightly faster. + + This option is enabled implicitly for SymbianOS, so there is no need +to specify it if you are using that target. + + The `--vfp11-denorm-fix' switch enables a link-time workaround for a +bug in certain VFP11 coprocessor hardware, which sometimes allows +instructions with denorm operands (which must be handled by support +code) to have those operands overwritten by subsequent instructions +before the support code can read the intended values. + + The bug may be avoided in scalar mode if you allow at least one +intervening instruction between a VFP11 instruction which uses a +register and another instruction which writes to the same register, or +at least two intervening instructions if vector mode is in use. The bug +only affects full-compliance floating-point mode: you do not need this +workaround if you are using "runfast" mode. Please contact ARM for +further details. + + If you know you are using buggy VFP11 hardware, you can enable this +workaround by specifying the linker option `--vfp-denorm-fix=scalar' if +you are using the VFP11 scalar mode only, or `--vfp-denorm-fix=vector' +if you are using vector mode (the latter also works for scalar code). +The default is `--vfp-denorm-fix=none'. + + If the workaround is enabled, instructions are scanned for +potentially-troublesome sequences, and a veneer is created for each +such sequence which may trigger the erratum. The veneer consists of the +first instruction of the sequence and a branch back to the subsequent +instruction. The original instruction is then replaced with a branch to +the veneer. The extra cycles required to call and return from the veneer +are sufficient to avoid the erratum in both the scalar and vector cases. + + The `--no-enum-size-warning' switch prevents the linker from warning +when linking object files that specify incompatible EABI enumeration +size attributes. For example, with this switch enabled, linking of an +object file using 32-bit enumeration values with another using +enumeration values fitted into the smallest possible space will not be +diagnosed. + + The `--no-wchar-size-warning' switch prevents the linker from +warning when linking object files that specify incompatible EABI +`wchar_t' size attributes. For example, with this switch enabled, +linking of an object file using 32-bit `wchar_t' values with another +using 16-bit `wchar_t' values will not be diagnosed. + + The `--pic-veneer' switch makes the linker use PIC sequences for +ARM/Thumb interworking veneers, even if the rest of the binary is not +PIC. This avoids problems on uClinux targets where `--emit-relocs' is +used to generate relocatable binaries. + + The linker will automatically generate and insert small sequences of +code into a linked ARM ELF executable whenever an attempt is made to +perform a function call to a symbol that is too far away. The +placement of these sequences of instructions - called stubs - is +controlled by the command line option `--stub-group-size=N'. The +placement is important because a poor choice can create a need for +duplicate stubs, increasing the code sizw. The linker will try to +group stubs together in order to reduce interruptions to the flow of +code, but it needs guidance as to how big these groups should be and +where they should be placed. + + The value of `N', the parameter to the `--stub-group-size=' option +controls where the stub groups are placed. If it is negative then all +stubs are placed after the first branch that needs them. If it is +positive then the stubs can be placed either before or after the +branches that need them. If the value of `N' is 1 (either +1 or -1) +then the linker will choose exactly where to place groups of stubs, +using its built in heuristics. A value of `N' greater than 1 (or +smaller than -1) tells the linker that a single group of stubs can +service at most `N' bytes from the input sections. + + The default, if `--stub-group-size=' is not specified, is `N = +1'. + + Farcalls stubs insertion is fully supported for the ARM-EABI target +only, because it relies on object files properties not present +otherwise. + + +File: ld.info, Node: HPPA ELF32, Next: M68K, Prev: ARM, Up: Machine Dependent + +4.5 `ld' and HPPA 32-bit ELF Support +==================================== + +When generating a shared library, `ld' will by default generate import +stubs suitable for use with a single sub-space application. The +`--multi-subspace' switch causes `ld' to generate export stubs, and +different (larger) import stubs suitable for use with multiple +sub-spaces. + + Long branch stubs and import/export stubs are placed by `ld' in stub +sections located between groups of input sections. `--stub-group-size' +specifies the maximum size of a group of input sections handled by one +stub section. Since branch offsets are signed, a stub section may +serve two groups of input sections, one group before the stub section, +and one group after it. However, when using conditional branches that +require stubs, it may be better (for branch prediction) that stub +sections only serve one group of input sections. A negative value for +`N' chooses this scheme, ensuring that branches to stubs always use a +negative offset. Two special values of `N' are recognized, `1' and +`-1'. These both instruct `ld' to automatically size input section +groups for the branch types detected, with the same behaviour regarding +stub placement as other positive or negative values of `N' respectively. + + Note that `--stub-group-size' does not split input sections. A +single input section larger than the group size specified will of course +create a larger group (of one section). If input sections are too +large, it may not be possible for a branch to reach its stub. + + +File: ld.info, Node: M68K, Next: MMIX, Prev: HPPA ELF32, Up: Machine Dependent + +4.6 `ld' and the Motorola 68K family +==================================== + +The `--got=TYPE' option lets you choose the GOT generation scheme. The +choices are `single', `negative', `multigot' and `target'. When +`target' is selected the linker chooses the default GOT generation +scheme for the current target. `single' tells the linker to generate a +single GOT with entries only at non-negative offsets. `negative' +instructs the linker to generate a single GOT with entries at both +negative and positive offsets. Not all environments support such GOTs. +`multigot' allows the linker to generate several GOTs in the output +file. All GOT references from a single input object file access the +same GOT, but references from different input object files might access +different GOTs. Not all environments support such GOTs. + + +File: ld.info, Node: MMIX, Next: MSP430, Prev: M68K, Up: Machine Dependent + +4.7 `ld' and MMIX +================= + +For MMIX, there is a choice of generating `ELF' object files or `mmo' +object files when linking. The simulator `mmix' understands the `mmo' +format. The binutils `objcopy' utility can translate between the two +formats. + + There is one special section, the `.MMIX.reg_contents' section. +Contents in this section is assumed to correspond to that of global +registers, and symbols referring to it are translated to special +symbols, equal to registers. In a final link, the start address of the +`.MMIX.reg_contents' section corresponds to the first allocated global +register multiplied by 8. Register `$255' is not included in this +section; it is always set to the program entry, which is at the symbol +`Main' for `mmo' files. + + Global symbols with the prefix `__.MMIX.start.', for example +`__.MMIX.start..text' and `__.MMIX.start..data' are special. The +default linker script uses these to set the default start address of a +section. + + Initial and trailing multiples of zero-valued 32-bit words in a +section, are left out from an mmo file. + + +File: ld.info, Node: MSP430, Next: M68HC11/68HC12, Prev: MMIX, Up: Machine Dependent + +4.8 `ld' and MSP430 +=================== + +For the MSP430 it is possible to select the MPU architecture. The flag +`-m [mpu type]' will select an appropriate linker script for selected +MPU type. (To get a list of known MPUs just pass `-m help' option to +the linker). + + The linker will recognize some extra sections which are MSP430 +specific: + +``.vectors'' + Defines a portion of ROM where interrupt vectors located. + +``.bootloader'' + Defines the bootloader portion of the ROM (if applicable). Any + code in this section will be uploaded to the MPU. + +``.infomem'' + Defines an information memory section (if applicable). Any code in + this section will be uploaded to the MPU. + +``.infomemnobits'' + This is the same as the `.infomem' section except that any code in + this section will not be uploaded to the MPU. + +``.noinit'' + Denotes a portion of RAM located above `.bss' section. + + The last two sections are used by gcc. + + +File: ld.info, Node: PowerPC ELF32, Next: PowerPC64 ELF64, Prev: M68HC11/68HC12, Up: Machine Dependent + +4.9 `ld' and PowerPC 32-bit ELF Support +======================================= + +Branches on PowerPC processors are limited to a signed 26-bit +displacement, which may result in `ld' giving `relocation truncated to +fit' errors with very large programs. `--relax' enables the generation +of trampolines that can access the entire 32-bit address space. These +trampolines are inserted at section boundaries, so may not themselves +be reachable if an input section exceeds 33M in size. You may combine +`-r' and `--relax' to add trampolines in a partial link. In that case +both branches to undefined symbols and inter-section branches are also +considered potentially out of range, and trampolines inserted. + +`--bss-plt' + Current PowerPC GCC accepts a `-msecure-plt' option that generates + code capable of using a newer PLT and GOT layout that has the + security advantage of no executable section ever needing to be + writable and no writable section ever being executable. PowerPC + `ld' will generate this layout, including stubs to access the PLT, + if all input files (including startup and static libraries) were + compiled with `-msecure-plt'. `--bss-plt' forces the old BSS PLT + (and GOT layout) which can give slightly better performance. + +`--secure-plt' + `ld' will use the new PLT and GOT layout if it is linking new + `-fpic' or `-fPIC' code, but does not do so automatically when + linking non-PIC code. This option requests the new PLT and GOT + layout. A warning will be given if some object file requires the + old style BSS PLT. + +`--sdata-got' + The new secure PLT and GOT are placed differently relative to other + sections compared to older BSS PLT and GOT placement. The + location of `.plt' must change because the new secure PLT is an + initialized section while the old PLT is uninitialized. The + reason for the `.got' change is more subtle: The new placement + allows `.got' to be read-only in applications linked with `-z + relro -z now'. However, this placement means that `.sdata' cannot + always be used in shared libraries, because the PowerPC ABI + accesses `.sdata' in shared libraries from the GOT pointer. + `--sdata-got' forces the old GOT placement. PowerPC GCC doesn't + use `.sdata' in shared libraries, so this option is really only + useful for other compilers that may do so. + +`--emit-stub-syms' + This option causes `ld' to label linker stubs with a local symbol + that encodes the stub type and destination. + +`--no-tls-optimize' + PowerPC `ld' normally performs some optimization of code sequences + used to access Thread-Local Storage. Use this option to disable + the optimization. + + +File: ld.info, Node: PowerPC64 ELF64, Next: SPU ELF, Prev: PowerPC ELF32, Up: Machine Dependent + +4.10 `ld' and PowerPC64 64-bit ELF Support +========================================== + +`--stub-group-size' + Long branch stubs, PLT call stubs and TOC adjusting stubs are + placed by `ld' in stub sections located between groups of input + sections. `--stub-group-size' specifies the maximum size of a + group of input sections handled by one stub section. Since branch + offsets are signed, a stub section may serve two groups of input + sections, one group before the stub section, and one group after + it. However, when using conditional branches that require stubs, + it may be better (for branch prediction) that stub sections only + serve one group of input sections. A negative value for `N' + chooses this scheme, ensuring that branches to stubs always use a + negative offset. Two special values of `N' are recognized, `1' + and `-1'. These both instruct `ld' to automatically size input + section groups for the branch types detected, with the same + behaviour regarding stub placement as other positive or negative + values of `N' respectively. + + Note that `--stub-group-size' does not split input sections. A + single input section larger than the group size specified will of + course create a larger group (of one section). If input sections + are too large, it may not be possible for a branch to reach its + stub. + +`--emit-stub-syms' + This option causes `ld' to label linker stubs with a local symbol + that encodes the stub type and destination. + +`--dotsyms, --no-dotsyms' + These two options control how `ld' interprets version patterns in + a version script. Older PowerPC64 compilers emitted both a + function descriptor symbol with the same name as the function, and + a code entry symbol with the name prefixed by a dot (`.'). To + properly version a function `foo', the version script thus needs + to control both `foo' and `.foo'. The option `--dotsyms', on by + default, automatically adds the required dot-prefixed patterns. + Use `--no-dotsyms' to disable this feature. + +`--no-tls-optimize' + PowerPC64 `ld' normally performs some optimization of code + sequences used to access Thread-Local Storage. Use this option to + disable the optimization. + +`--no-opd-optimize' + PowerPC64 `ld' normally removes `.opd' section entries + corresponding to deleted link-once functions, or functions removed + by the action of `--gc-sections' or linker script `/DISCARD/'. + Use this option to disable `.opd' optimization. + +`--non-overlapping-opd' + Some PowerPC64 compilers have an option to generate compressed + `.opd' entries spaced 16 bytes apart, overlapping the third word, + the static chain pointer (unused in C) with the first word of the + next entry. This option expands such entries to the full 24 bytes. + +`--no-toc-optimize' + PowerPC64 `ld' normally removes unused `.toc' section entries. + Such entries are detected by examining relocations that reference + the TOC in code sections. A reloc in a deleted code section marks + a TOC word as unneeded, while a reloc in a kept code section marks + a TOC word as needed. Since the TOC may reference itself, TOC + relocs are also examined. TOC words marked as both needed and + unneeded will of course be kept. TOC words without any referencing + reloc are assumed to be part of a multi-word entry, and are kept or + discarded as per the nearest marked preceding word. This works + reliably for compiler generated code, but may be incorrect if + assembly code is used to insert TOC entries. Use this option to + disable the optimization. + +`--no-multi-toc' + By default, PowerPC64 GCC generates code for a TOC model where TOC + entries are accessed with a 16-bit offset from r2. This limits the + total TOC size to 64K. PowerPC64 `ld' extends this limit by + grouping code sections such that each group uses less than 64K for + its TOC entries, then inserts r2 adjusting stubs between + inter-group calls. `ld' does not split apart input sections, so + cannot help if a single input file has a `.toc' section that + exceeds 64K, most likely from linking multiple files with `ld -r'. + Use this option to turn off this feature. + + +File: ld.info, Node: SPU ELF, Next: TI COFF, Prev: PowerPC64 ELF64, Up: Machine Dependent + +4.11 `ld' and SPU ELF Support +============================= + +`--plugin' + This option marks an executable as a PIC plugin module. + +`--no-overlays' + Normally, `ld' recognizes calls to functions within overlay + regions, and redirects such calls to an overlay manager via a stub. + `ld' also provides a built-in overlay manager. This option turns + off all this special overlay handling. + +`--emit-stub-syms' + This option causes `ld' to label overlay stubs with a local symbol + that encodes the stub type and destination. + +`--extra-overlay-stubs' + This option causes `ld' to add overlay call stubs on all function + calls out of overlay regions. Normally stubs are not added on + calls to non-overlay regions. + +`--local-store=lo:hi' + `ld' usually checks that a final executable for SPU fits in the + address range 0 to 256k. This option may be used to change the + range. Disable the check entirely with `--local-store=0:0'. + +`--stack-analysis' + SPU local store space is limited. Over-allocation of stack space + unnecessarily limits space available for code and data, while + under-allocation results in runtime failures. If given this + option, `ld' will provide an estimate of maximum stack usage. + `ld' does this by examining symbols in code sections to determine + the extents of functions, and looking at function prologues for + stack adjusting instructions. A call-graph is created by looking + for relocations on branch instructions. The graph is then searched + for the maximum stack usage path. Note that this analysis does not + find calls made via function pointers, and does not handle + recursion and other cycles in the call graph. Stack usage may be + under-estimated if your code makes such calls. Also, stack usage + for dynamic allocation, e.g. alloca, will not be detected. If a + link map is requested, detailed information about each function's + stack usage and calls will be given. + +`--emit-stack-syms' + This option, if given along with `--stack-analysis' will result in + `ld' emitting stack sizing symbols for each function. These take + the form `__stack_<function_name>' for global functions, and + `__stack_<number>_<function_name>' for static functions. + `<number>' is the section id in hex. The value of such symbols is + the stack requirement for the corresponding function. The symbol + size will be zero, type `STT_NOTYPE', binding `STB_LOCAL', and + section `SHN_ABS'. + + +File: ld.info, Node: TI COFF, Next: WIN32, Prev: SPU ELF, Up: Machine Dependent + +4.12 `ld''s Support for Various TI COFF Versions +================================================ + +The `--format' switch allows selection of one of the various TI COFF +versions. The latest of this writing is 2; versions 0 and 1 are also +supported. The TI COFF versions also vary in header byte-order format; +`ld' will read any version or byte order, but the output header format +depends on the default specified by the specific target. + + +File: ld.info, Node: WIN32, Next: Xtensa, Prev: TI COFF, Up: Machine Dependent + +4.13 `ld' and WIN32 (cygwin/mingw) +================================== + +This section describes some of the win32 specific `ld' issues. See +*Note Command Line Options: Options. for detailed description of the +command line options mentioned here. + +_import libraries_ + The standard Windows linker creates and uses so-called import + libraries, which contains information for linking to dll's. They + are regular static archives and are handled as any other static + archive. The cygwin and mingw ports of `ld' have specific support + for creating such libraries provided with the `--out-implib' + command line option. + +_exporting DLL symbols_ + The cygwin/mingw `ld' has several ways to export symbols for dll's. + + _using auto-export functionality_ + By default `ld' exports symbols with the auto-export + functionality, which is controlled by the following command + line options: + + * -export-all-symbols [This is the default] + + * -exclude-symbols + + * -exclude-libs + + * -exclude-modules-for-implib + + * -version-script + + When auto-export is in operation, `ld' will export all the + non-local (global and common) symbols it finds in a DLL, with + the exception of a few symbols known to belong to the + system's runtime and libraries. As it will often not be + desirable to export all of a DLL's symbols, which may include + private functions that are not part of any public interface, + the command-line options listed above may be used to filter + symbols out from the list for exporting. The `--output-def' + option can be used in order to see the final list of exported + symbols with all exclusions taken into effect. + + If `--export-all-symbols' is not given explicitly on the + command line, then the default auto-export behavior will be + _disabled_ if either of the following are true: + + * A DEF file is used. + + * Any symbol in any object file was marked with the + __declspec(dllexport) attribute. + + _using a DEF file_ + Another way of exporting symbols is using a DEF file. A DEF + file is an ASCII file containing definitions of symbols which + should be exported when a dll is created. Usually it is + named `<dll name>.def' and is added as any other object file + to the linker's command line. The file's name must end in + `.def' or `.DEF'. + + gcc -o <output> <objectfiles> <dll name>.def + + Using a DEF file turns off the normal auto-export behavior, + unless the `--export-all-symbols' option is also used. + + Here is an example of a DEF file for a shared library called + `xyz.dll': + + LIBRARY "xyz.dll" BASE=0x20000000 + + EXPORTS + foo + bar + _bar = bar + another_foo = abc.dll.afoo + var1 DATA + + This example defines a DLL with a non-default base address + and five symbols in the export table. The third exported + symbol `_bar' is an alias for the second. The fourth symbol, + `another_foo' is resolved by "forwarding" to another module + and treating it as an alias for `afoo' exported from the DLL + `abc.dll'. The final symbol `var1' is declared to be a data + object. + + The optional `LIBRARY <name>' command indicates the _internal_ + name of the output DLL. If `<name>' does not include a suffix, + the default library suffix, `.DLL' is appended. + + When the .DEF file is used to build an application, rather + than a library, the `NAME <name>' command should be used + instead of `LIBRARY'. If `<name>' does not include a suffix, + the default executable suffix, `.EXE' is appended. + + With either `LIBRARY <name>' or `NAME <name>' the optional + specification `BASE = <number>' may be used to specify a + non-default base address for the image. + + If neither `LIBRARY <name>' nor `NAME <name>' is specified, + or they specify an empty string, the internal name is the + same as the filename specified on the command line. + + The complete specification of an export symbol is: + + EXPORTS + ( ( ( <name1> [ = <name2> ] ) + | ( <name1> = <module-name> . <external-name>)) + [ @ <integer> ] [NONAME] [DATA] [CONSTANT] [PRIVATE] ) * + + Declares `<name1>' as an exported symbol from the DLL, or + declares `<name1>' as an exported alias for `<name2>'; or + declares `<name1>' as a "forward" alias for the symbol + `<external-name>' in the DLL `<module-name>'. Optionally, + the symbol may be exported by the specified ordinal + `<integer>' alias. + + The optional keywords that follow the declaration indicate: + + `NONAME': Do not put the symbol name in the DLL's export + table. It will still be exported by its ordinal alias + (either the value specified by the .def specification or, + otherwise, the value assigned by the linker). The symbol + name, however, does remain visible in the import library (if + any), unless `PRIVATE' is also specified. + + `DATA': The symbol is a variable or object, rather than a + function. The import lib will export only an indirect + reference to `foo' as the symbol `_imp__foo' (ie, `foo' must + be resolved as `*_imp__foo'). + + `CONSTANT': Like `DATA', but put the undecorated `foo' as + well as `_imp__foo' into the import library. Both refer to the + read-only import address table's pointer to the variable, not + to the variable itself. This can be dangerous. If the user + code fails to add the `dllimport' attribute and also fails to + explicitly add the extra indirection that the use of the + attribute enforces, the application will behave unexpectedly. + + `PRIVATE': Put the symbol in the DLL's export table, but do + not put it into the static import library used to resolve + imports at link time. The symbol can still be imported using + the `LoadLibrary/GetProcAddress' API at runtime or by by + using the GNU ld extension of linking directly to the DLL + without an import library. + + See ld/deffilep.y in the binutils sources for the full + specification of other DEF file statements + + While linking a shared dll, `ld' is able to create a DEF file + with the `--output-def <file>' command line option. + + _Using decorations_ + Another way of marking symbols for export is to modify the + source code itself, so that when building the DLL each symbol + to be exported is declared as: + + __declspec(dllexport) int a_variable + __declspec(dllexport) void a_function(int with_args) + + All such symbols will be exported from the DLL. If, however, + any of the object files in the DLL contain symbols decorated + in this way, then the normal auto-export behavior is + disabled, unless the `--export-all-symbols' option is also + used. + + Note that object files that wish to access these symbols must + _not_ decorate them with dllexport. Instead, they should use + dllimport, instead: + + __declspec(dllimport) int a_variable + __declspec(dllimport) void a_function(int with_args) + + This complicates the structure of library header files, + because when included by the library itself the header must + declare the variables and functions as dllexport, but when + included by client code the header must declare them as + dllimport. There are a number of idioms that are typically + used to do this; often client code can omit the __declspec() + declaration completely. See `--enable-auto-import' and + `automatic data imports' for more information. + +_automatic data imports_ + The standard Windows dll format supports data imports from dlls + only by adding special decorations (dllimport/dllexport), which + let the compiler produce specific assembler instructions to deal + with this issue. This increases the effort necessary to port + existing Un*x code to these platforms, especially for large c++ + libraries and applications. The auto-import feature, which was + initially provided by Paul Sokolovsky, allows one to omit the + decorations to achieve a behavior that conforms to that on + POSIX/Un*x platforms. This feature is enabled with the + `--enable-auto-import' command-line option, although it is enabled + by default on cygwin/mingw. The `--enable-auto-import' option + itself now serves mainly to suppress any warnings that are + ordinarily emitted when linked objects trigger the feature's use. + + auto-import of variables does not always work flawlessly without + additional assistance. Sometimes, you will see this message + + "variable '<var>' can't be auto-imported. Please read the + documentation for ld's `--enable-auto-import' for details." + + The `--enable-auto-import' documentation explains why this error + occurs, and several methods that can be used to overcome this + difficulty. One of these methods is the _runtime pseudo-relocs_ + feature, described below. + + For complex variables imported from DLLs (such as structs or + classes), object files typically contain a base address for the + variable and an offset (_addend_) within the variable-to specify a + particular field or public member, for instance. Unfortunately, + the runtime loader used in win32 environments is incapable of + fixing these references at runtime without the additional + information supplied by dllimport/dllexport decorations. The + standard auto-import feature described above is unable to resolve + these references. + + The `--enable-runtime-pseudo-relocs' switch allows these + references to be resolved without error, while leaving the task of + adjusting the references themselves (with their non-zero addends) + to specialized code provided by the runtime environment. Recent + versions of the cygwin and mingw environments and compilers + provide this runtime support; older versions do not. However, the + support is only necessary on the developer's platform; the + compiled result will run without error on an older system. + + `--enable-runtime-pseudo-relocs' is not the default; it must be + explicitly enabled as needed. + +_direct linking to a dll_ + The cygwin/mingw ports of `ld' support the direct linking, + including data symbols, to a dll without the usage of any import + libraries. This is much faster and uses much less memory than + does the traditional import library method, especially when + linking large libraries or applications. When `ld' creates an + import lib, each function or variable exported from the dll is + stored in its own bfd, even though a single bfd could contain many + exports. The overhead involved in storing, loading, and + processing so many bfd's is quite large, and explains the + tremendous time, memory, and storage needed to link against + particularly large or complex libraries when using import libs. + + Linking directly to a dll uses no extra command-line switches + other than `-L' and `-l', because `ld' already searches for a + number of names to match each library. All that is needed from + the developer's perspective is an understanding of this search, in + order to force ld to select the dll instead of an import library. + + For instance, when ld is called with the argument `-lxxx' it will + attempt to find, in the first directory of its search path, + + libxxx.dll.a + xxx.dll.a + libxxx.a + xxx.lib + cygxxx.dll (*) + libxxx.dll + xxx.dll + + before moving on to the next directory in the search path. + + (*) Actually, this is not `cygxxx.dll' but in fact is + `<prefix>xxx.dll', where `<prefix>' is set by the `ld' option + `--dll-search-prefix=<prefix>'. In the case of cygwin, the + standard gcc spec file includes `--dll-search-prefix=cyg', so in + effect we actually search for `cygxxx.dll'. + + Other win32-based unix environments, such as mingw or pw32, may + use other `<prefix>'es, although at present only cygwin makes use + of this feature. It was originally intended to help avoid name + conflicts among dll's built for the various win32/un*x + environments, so that (for example) two versions of a zlib dll + could coexist on the same machine. + + The generic cygwin/mingw path layout uses a `bin' directory for + applications and dll's and a `lib' directory for the import + libraries (using cygwin nomenclature): + + bin/ + cygxxx.dll + lib/ + libxxx.dll.a (in case of dll's) + libxxx.a (in case of static archive) + + Linking directly to a dll without using the import library can be + done two ways: + + 1. Use the dll directly by adding the `bin' path to the link line + gcc -Wl,-verbose -o a.exe -L../bin/ -lxxx + + However, as the dll's often have version numbers appended to their + names (`cygncurses-5.dll') this will often fail, unless one + specifies `-L../bin -lncurses-5' to include the version. Import + libs are generally not versioned, and do not have this difficulty. + + 2. Create a symbolic link from the dll to a file in the `lib' + directory according to the above mentioned search pattern. This + should be used to avoid unwanted changes in the tools needed for + making the app/dll. + + ln -s bin/cygxxx.dll lib/[cyg|lib|]xxx.dll[.a] + + Then you can link without any make environment changes. + + gcc -Wl,-verbose -o a.exe -L../lib/ -lxxx + + This technique also avoids the version number problems, because + the following is perfectly legal + + bin/ + cygxxx-5.dll + lib/ + libxxx.dll.a -> ../bin/cygxxx-5.dll + + Linking directly to a dll without using an import lib will work + even when auto-import features are exercised, and even when + `--enable-runtime-pseudo-relocs' is used. + + Given the improvements in speed and memory usage, one might + justifiably wonder why import libraries are used at all. There + are three reasons: + + 1. Until recently, the link-directly-to-dll functionality did _not_ + work with auto-imported data. + + 2. Sometimes it is necessary to include pure static objects within + the import library (which otherwise contains only bfd's for + indirection symbols that point to the exports of a dll). Again, + the import lib for the cygwin kernel makes use of this ability, + and it is not possible to do this without an import lib. + + 3. Symbol aliases can only be resolved using an import lib. This + is critical when linking against OS-supplied dll's (eg, the win32 + API) in which symbols are usually exported as undecorated aliases + of their stdcall-decorated assembly names. + + So, import libs are not going away. But the ability to replace + true import libs with a simple symbolic link to (or a copy of) a + dll, in many cases, is a useful addition to the suite of tools + binutils makes available to the win32 developer. Given the + massive improvements in memory requirements during linking, storage + requirements, and linking speed, we expect that many developers + will soon begin to use this feature whenever possible. + +_symbol aliasing_ + + _adding additional names_ + Sometimes, it is useful to export symbols with additional + names. A symbol `foo' will be exported as `foo', but it can + also be exported as `_foo' by using special directives in the + DEF file when creating the dll. This will affect also the + optional created import library. Consider the following DEF + file: + + LIBRARY "xyz.dll" BASE=0x61000000 + + EXPORTS + foo + _foo = foo + + The line `_foo = foo' maps the symbol `foo' to `_foo'. + + Another method for creating a symbol alias is to create it in + the source code using the "weak" attribute: + + void foo () { /* Do something. */; } + void _foo () __attribute__ ((weak, alias ("foo"))); + + See the gcc manual for more information about attributes and + weak symbols. + + _renaming symbols_ + Sometimes it is useful to rename exports. For instance, the + cygwin kernel does this regularly. A symbol `_foo' can be + exported as `foo' but not as `_foo' by using special + directives in the DEF file. (This will also affect the import + library, if it is created). In the following example: + + LIBRARY "xyz.dll" BASE=0x61000000 + + EXPORTS + _foo = foo + + The line `_foo = foo' maps the exported symbol `foo' to + `_foo'. + + Note: using a DEF file disables the default auto-export behavior, + unless the `--export-all-symbols' command line option is used. + If, however, you are trying to rename symbols, then you should list + _all_ desired exports in the DEF file, including the symbols that + are not being renamed, and do _not_ use the `--export-all-symbols' + option. If you list only the renamed symbols in the DEF file, and + use `--export-all-symbols' to handle the other symbols, then the + both the new names _and_ the original names for the renamed + symbols will be exported. In effect, you'd be aliasing those + symbols, not renaming them, which is probably not what you wanted. + +_weak externals_ + The Windows object format, PE, specifies a form of weak symbols + called weak externals. When a weak symbol is linked and the + symbol is not defined, the weak symbol becomes an alias for some + other symbol. There are three variants of weak externals: + * Definition is searched for in objects and libraries, + historically called lazy externals. + + * Definition is searched for only in other objects, not in + libraries. This form is not presently implemented. + + * No search; the symbol is an alias. This form is not presently + implemented. + As a GNU extension, weak symbols that do not specify an alternate + symbol are supported. If the symbol is undefined when linking, + the symbol uses a default value. + +_aligned common symbols_ + As a GNU extension to the PE file format, it is possible to + specify the desired alignment for a common symbol. This + information is conveyed from the assembler or compiler to the + linker by means of GNU-specific commands carried in the object + file's `.drectve' section, which are recognized by `ld' and + respected when laying out the common symbols. Native tools will + be able to process object files employing this GNU extension, but + will fail to respect the alignment instructions, and may issue + noisy warnings about unknown linker directives. + + +File: ld.info, Node: Xtensa, Prev: WIN32, Up: Machine Dependent + +4.14 `ld' and Xtensa Processors +=============================== + +The default `ld' behavior for Xtensa processors is to interpret +`SECTIONS' commands so that lists of explicitly named sections in a +specification with a wildcard file will be interleaved when necessary to +keep literal pools within the range of PC-relative load offsets. For +example, with the command: + + SECTIONS + { + .text : { + *(.literal .text) + } + } + +`ld' may interleave some of the `.literal' and `.text' sections from +different object files to ensure that the literal pools are within the +range of PC-relative load offsets. A valid interleaving might place +the `.literal' sections from an initial group of files followed by the +`.text' sections of that group of files. Then, the `.literal' sections +from the rest of the files and the `.text' sections from the rest of +the files would follow. + + Relaxation is enabled by default for the Xtensa version of `ld' and +provides two important link-time optimizations. The first optimization +is to combine identical literal values to reduce code size. A redundant +literal will be removed and all the `L32R' instructions that use it +will be changed to reference an identical literal, as long as the +location of the replacement literal is within the offset range of all +the `L32R' instructions. The second optimization is to remove +unnecessary overhead from assembler-generated "longcall" sequences of +`L32R'/`CALLXN' when the target functions are within range of direct +`CALLN' instructions. + + For each of these cases where an indirect call sequence can be +optimized to a direct call, the linker will change the `CALLXN' +instruction to a `CALLN' instruction, remove the `L32R' instruction, +and remove the literal referenced by the `L32R' instruction if it is +not used for anything else. Removing the `L32R' instruction always +reduces code size but can potentially hurt performance by changing the +alignment of subsequent branch targets. By default, the linker will +always preserve alignments, either by switching some instructions +between 24-bit encodings and the equivalent density instructions or by +inserting a no-op in place of the `L32R' instruction that was removed. +If code size is more important than performance, the `--size-opt' +option can be used to prevent the linker from widening density +instructions or inserting no-ops, except in a few cases where no-ops +are required for correctness. + + The following Xtensa-specific command-line options can be used to +control the linker: + +`--no-relax' + Since the Xtensa version of `ld' enables the `--relax' option by + default, the `--no-relax' option is provided to disable relaxation. + +`--size-opt' + When optimizing indirect calls to direct calls, optimize for code + size more than performance. With this option, the linker will not + insert no-ops or widen density instructions to preserve branch + target alignment. There may still be some cases where no-ops are + required to preserve the correctness of the code. + + +File: ld.info, Node: BFD, Next: Reporting Bugs, Prev: Machine Dependent, Up: Top + +5 BFD +***** + +The linker accesses object and archive files using the BFD libraries. +These libraries allow the linker to use the same routines to operate on +object files whatever the object file format. A different object file +format can be supported simply by creating a new BFD back end and adding +it to the library. To conserve runtime memory, however, the linker and +associated tools are usually configured to support only a subset of the +object file formats available. You can use `objdump -i' (*note +objdump: (binutils.info)objdump.) to list all the formats available for +your configuration. + + As with most implementations, BFD is a compromise between several +conflicting requirements. The major factor influencing BFD design was +efficiency: any time used converting between formats is time which +would not have been spent had BFD not been involved. This is partly +offset by abstraction payback; since BFD simplifies applications and +back ends, more time and care may be spent optimizing algorithms for a +greater speed. + + One minor artifact of the BFD solution which you should bear in mind +is the potential for information loss. There are two places where +useful information can be lost using the BFD mechanism: during +conversion and during output. *Note BFD information loss::. + +* Menu: + +* BFD outline:: How it works: an outline of BFD + + +File: ld.info, Node: BFD outline, Up: BFD + +5.1 How It Works: An Outline of BFD +=================================== + +When an object file is opened, BFD subroutines automatically determine +the format of the input object file. They then build a descriptor in +memory with pointers to routines that will be used to access elements of +the object file's data structures. + + As different information from the object files is required, BFD +reads from different sections of the file and processes them. For +example, a very common operation for the linker is processing symbol +tables. Each BFD back end provides a routine for converting between +the object file's representation of symbols and an internal canonical +format. When the linker asks for the symbol table of an object file, it +calls through a memory pointer to the routine from the relevant BFD +back end which reads and converts the table into a canonical form. The +linker then operates upon the canonical form. When the link is finished +and the linker writes the output file's symbol table, another BFD back +end routine is called to take the newly created symbol table and +convert it into the chosen output format. + +* Menu: + +* BFD information loss:: Information Loss +* Canonical format:: The BFD canonical object-file format + + +File: ld.info, Node: BFD information loss, Next: Canonical format, Up: BFD outline + +5.1.1 Information Loss +---------------------- + +_Information can be lost during output._ The output formats supported +by BFD do not provide identical facilities, and information which can +be described in one form has nowhere to go in another format. One +example of this is alignment information in `b.out'. There is nowhere +in an `a.out' format file to store alignment information on the +contained data, so when a file is linked from `b.out' and an `a.out' +image is produced, alignment information will not propagate to the +output file. (The linker will still use the alignment information +internally, so the link is performed correctly). + + Another example is COFF section names. COFF files may contain an +unlimited number of sections, each one with a textual section name. If +the target of the link is a format which does not have many sections +(e.g., `a.out') or has sections without names (e.g., the Oasys format), +the link cannot be done simply. You can circumvent this problem by +describing the desired input-to-output section mapping with the linker +command language. + + _Information can be lost during canonicalization._ The BFD internal +canonical form of the external formats is not exhaustive; there are +structures in input formats for which there is no direct representation +internally. This means that the BFD back ends cannot maintain all +possible data richness through the transformation between external to +internal and back to external formats. + + This limitation is only a problem when an application reads one +format and writes another. Each BFD back end is responsible for +maintaining as much data as possible, and the internal BFD canonical +form has structures which are opaque to the BFD core, and exported only +to the back ends. When a file is read in one format, the canonical form +is generated for BFD and the application. At the same time, the back +end saves away any information which may otherwise be lost. If the data +is then written back in the same format, the back end routine will be +able to use the canonical form provided by the BFD core as well as the +information it prepared earlier. Since there is a great deal of +commonality between back ends, there is no information lost when +linking or copying big endian COFF to little endian COFF, or `a.out' to +`b.out'. When a mixture of formats is linked, the information is only +lost from the files whose format differs from the destination. + + +File: ld.info, Node: Canonical format, Prev: BFD information loss, Up: BFD outline + +5.1.2 The BFD canonical object-file format +------------------------------------------ + +The greatest potential for loss of information occurs when there is the +least overlap between the information provided by the source format, +that stored by the canonical format, and that needed by the destination +format. A brief description of the canonical form may help you +understand which kinds of data you can count on preserving across +conversions. + +_files_ + Information stored on a per-file basis includes target machine + architecture, particular implementation format type, a demand + pageable bit, and a write protected bit. Information like Unix + magic numbers is not stored here--only the magic numbers' meaning, + so a `ZMAGIC' file would have both the demand pageable bit and the + write protected text bit set. The byte order of the target is + stored on a per-file basis, so that big- and little-endian object + files may be used with one another. + +_sections_ + Each section in the input file contains the name of the section, + the section's original address in the object file, size and + alignment information, various flags, and pointers into other BFD + data structures. + +_symbols_ + Each symbol contains a pointer to the information for the object + file which originally defined it, its name, its value, and various + flag bits. When a BFD back end reads in a symbol table, it + relocates all symbols to make them relative to the base of the + section where they were defined. Doing this ensures that each + symbol points to its containing section. Each symbol also has a + varying amount of hidden private data for the BFD back end. Since + the symbol points to the original file, the private data format + for that symbol is accessible. `ld' can operate on a collection + of symbols of wildly different formats without problems. + + Normal global and simple local symbols are maintained on output, + so an output file (no matter its format) will retain symbols + pointing to functions and to global, static, and common variables. + Some symbol information is not worth retaining; in `a.out', type + information is stored in the symbol table as long symbol names. + This information would be useless to most COFF debuggers; the + linker has command line switches to allow users to throw it away. + + There is one word of type information within the symbol, so if the + format supports symbol type information within symbols (for + example, COFF, IEEE, Oasys) and the type is simple enough to fit + within one word (nearly everything but aggregates), the + information will be preserved. + +_relocation level_ + Each canonical BFD relocation record contains a pointer to the + symbol to relocate to, the offset of the data to relocate, the + section the data is in, and a pointer to a relocation type + descriptor. Relocation is performed by passing messages through + the relocation type descriptor and the symbol pointer. Therefore, + relocations can be performed on output data using a relocation + method that is only available in one of the input formats. For + instance, Oasys provides a byte relocation format. A relocation + record requesting this relocation type would point indirectly to a + routine to perform this, so the relocation may be performed on a + byte being written to a 68k COFF file, even though 68k COFF has no + such relocation type. + +_line numbers_ + Object formats can contain, for debugging purposes, some form of + mapping between symbols, source line numbers, and addresses in the + output file. These addresses have to be relocated along with the + symbol information. Each symbol with an associated list of line + number records points to the first record of the list. The head + of a line number list consists of a pointer to the symbol, which + allows finding out the address of the function whose line number + is being described. The rest of the list is made up of pairs: + offsets into the section and line numbers. Any format which can + simply derive this information can pass it successfully between + formats (COFF, IEEE and Oasys). + + +File: ld.info, Node: Reporting Bugs, Next: MRI, Prev: BFD, Up: Top + +6 Reporting Bugs +**************** + +Your bug reports play an essential role in making `ld' reliable. + + Reporting a bug may help you by bringing a solution to your problem, +or it may not. But in any case the principal function of a bug report +is to help the entire community by making the next version of `ld' work +better. Bug reports are your contribution to the maintenance of `ld'. + + In order for a bug report to serve its purpose, you must include the +information that enables us to fix the bug. + +* Menu: + +* Bug Criteria:: Have you found a bug? +* Bug Reporting:: How to report bugs + + +File: ld.info, Node: Bug Criteria, Next: Bug Reporting, Up: Reporting Bugs + +6.1 Have You Found a Bug? +========================= + +If you are not sure whether you have found a bug, here are some +guidelines: + + * If the linker gets a fatal signal, for any input whatever, that is + a `ld' bug. Reliable linkers never crash. + + * If `ld' produces an error message for valid input, that is a bug. + + * If `ld' does not produce an error message for invalid input, that + may be a bug. In the general case, the linker can not verify that + object files are correct. + + * If you are an experienced user of linkers, your suggestions for + improvement of `ld' are welcome in any case. + + +File: ld.info, Node: Bug Reporting, Prev: Bug Criteria, Up: Reporting Bugs + +6.2 How to Report Bugs +====================== + +A number of companies and individuals offer support for GNU products. +If you obtained `ld' from a support organization, we recommend you +contact that organization first. + + You can find contact information for many support companies and +individuals in the file `etc/SERVICE' in the GNU Emacs distribution. + + Otherwise, send bug reports for `ld' to +`http://www.sourceware.org/bugzilla/'. + + The fundamental principle of reporting bugs usefully is this: +*report all the facts*. If you are not sure whether to state a fact or +leave it out, state it! + + Often people omit facts because they think they know what causes the +problem and assume that some details do not matter. Thus, you might +assume that the name of a symbol you use in an example does not matter. +Well, probably it does not, but one cannot be sure. Perhaps the bug +is a stray memory reference which happens to fetch from the location +where that name is stored in memory; perhaps, if the name were +different, the contents of that location would fool the linker into +doing the right thing despite the bug. Play it safe and give a +specific, complete example. That is the easiest thing for you to do, +and the most helpful. + + Keep in mind that the purpose of a bug report is to enable us to fix +the bug if it is new to us. Therefore, always write your bug reports +on the assumption that the bug has not been reported previously. + + Sometimes people give a few sketchy facts and ask, "Does this ring a +bell?" This cannot help us fix a bug, so it is basically useless. We +respond by asking for enough details to enable us to investigate. You +might as well expedite matters by sending them to begin with. + + To enable us to fix the bug, you should include all these things: + + * The version of `ld'. `ld' announces it if you start it with the + `--version' argument. + + Without this, we will not know whether there is any point in + looking for the bug in the current version of `ld'. + + * Any patches you may have applied to the `ld' source, including any + patches made to the `BFD' library. + + * The type of machine you are using, and the operating system name + and version number. + + * What compiler (and its version) was used to compile `ld'--e.g. + "`gcc-2.7'". + + * The command arguments you gave the linker to link your example and + observe the bug. To guarantee you will not omit something + important, list them all. A copy of the Makefile (or the output + from make) is sufficient. + + If we were to try to guess the arguments, we would probably guess + wrong and then we might not encounter the bug. + + * A complete input file, or set of input files, that will reproduce + the bug. It is generally most helpful to send the actual object + files provided that they are reasonably small. Say no more than + 10K. For bigger files you can either make them available by FTP + or HTTP or else state that you are willing to send the object + file(s) to whomever requests them. (Note - your email will be + going to a mailing list, so we do not want to clog it up with + large attachments). But small attachments are best. + + If the source files were assembled using `gas' or compiled using + `gcc', then it may be OK to send the source files rather than the + object files. In this case, be sure to say exactly what version of + `gas' or `gcc' was used to produce the object files. Also say how + `gas' or `gcc' were configured. + + * A description of what behavior you observe that you believe is + incorrect. For example, "It gets a fatal signal." + + Of course, if the bug is that `ld' gets a fatal signal, then we + will certainly notice it. But if the bug is incorrect output, we + might not notice unless it is glaringly wrong. You might as well + not give us a chance to make a mistake. + + Even if the problem you experience is a fatal signal, you should + still say so explicitly. Suppose something strange is going on, + such as, your copy of `ld' is out of sync, or you have encountered + a bug in the C library on your system. (This has happened!) Your + copy might crash and ours would not. If you told us to expect a + crash, then when ours fails to crash, we would know that the bug + was not happening for us. If you had not told us to expect a + crash, then we would not be able to draw any conclusion from our + observations. + + * If you wish to suggest changes to the `ld' source, send us context + diffs, as generated by `diff' with the `-u', `-c', or `-p' option. + Always send diffs from the old file to the new file. If you even + discuss something in the `ld' source, refer to it by context, not + by line number. + + The line numbers in our development sources will not match those + in your sources. Your line numbers would convey no useful + information to us. + + Here are some things that are not necessary: + + * A description of the envelope of the bug. + + Often people who encounter a bug spend a lot of time investigating + which changes to the input file will make the bug go away and which + changes will not affect it. + + This is often time consuming and not very useful, because the way + we will find the bug is by running a single example under the + debugger with breakpoints, not by pure deduction from a series of + examples. We recommend that you save your time for something else. + + Of course, if you can find a simpler example to report _instead_ + of the original one, that is a convenience for us. Errors in the + output will be easier to spot, running under the debugger will take + less time, and so on. + + However, simplification is not vital; if you do not want to do + this, report the bug anyway and send us the entire test case you + used. + + * A patch for the bug. + + A patch for the bug does help us if it is a good one. But do not + omit the necessary information, such as the test case, on the + assumption that a patch is all we need. We might see problems + with your patch and decide to fix the problem another way, or we + might not understand it at all. + + Sometimes with a program as complicated as `ld' it is very hard to + construct an example that will make the program follow a certain + path through the code. If you do not send us the example, we will + not be able to construct one, so we will not be able to verify + that the bug is fixed. + + And if we cannot understand what bug you are trying to fix, or why + your patch should be an improvement, we will not install it. A + test case will help us to understand. + + * A guess about what the bug is or what it depends on. + + Such guesses are usually wrong. Even we cannot guess right about + such things without first using the debugger to find the facts. + + +File: ld.info, Node: MRI, Next: GNU Free Documentation License, Prev: Reporting Bugs, Up: Top + +Appendix A MRI Compatible Script Files +************************************** + +To aid users making the transition to GNU `ld' from the MRI linker, +`ld' can use MRI compatible linker scripts as an alternative to the +more general-purpose linker scripting language described in *Note +Scripts::. MRI compatible linker scripts have a much simpler command +set than the scripting language otherwise used with `ld'. GNU `ld' +supports the most commonly used MRI linker commands; these commands are +described here. + + In general, MRI scripts aren't of much use with the `a.out' object +file format, since it only has three sections and MRI scripts lack some +features to make use of them. + + You can specify a file containing an MRI-compatible script using the +`-c' command-line option. + + Each command in an MRI-compatible script occupies its own line; each +command line starts with the keyword that identifies the command (though +blank lines are also allowed for punctuation). If a line of an +MRI-compatible script begins with an unrecognized keyword, `ld' issues +a warning message, but continues processing the script. + + Lines beginning with `*' are comments. + + You can write these commands using all upper-case letters, or all +lower case; for example, `chip' is the same as `CHIP'. The following +list shows only the upper-case form of each command. + +`ABSOLUTE SECNAME' +`ABSOLUTE SECNAME, SECNAME, ... SECNAME' + Normally, `ld' includes in the output file all sections from all + the input files. However, in an MRI-compatible script, you can + use the `ABSOLUTE' command to restrict the sections that will be + present in your output program. If the `ABSOLUTE' command is used + at all in a script, then only the sections named explicitly in + `ABSOLUTE' commands will appear in the linker output. You can + still use other input sections (whatever you select on the command + line, or using `LOAD') to resolve addresses in the output file. + +`ALIAS OUT-SECNAME, IN-SECNAME' + Use this command to place the data from input section IN-SECNAME + in a section called OUT-SECNAME in the linker output file. + + IN-SECNAME may be an integer. + +`ALIGN SECNAME = EXPRESSION' + Align the section called SECNAME to EXPRESSION. The EXPRESSION + should be a power of two. + +`BASE EXPRESSION' + Use the value of EXPRESSION as the lowest address (other than + absolute addresses) in the output file. + +`CHIP EXPRESSION' +`CHIP EXPRESSION, EXPRESSION' + This command does nothing; it is accepted only for compatibility. + +`END' + This command does nothing whatever; it's only accepted for + compatibility. + +`FORMAT OUTPUT-FORMAT' + Similar to the `OUTPUT_FORMAT' command in the more general linker + language, but restricted to one of these output formats: + + 1. S-records, if OUTPUT-FORMAT is `S' + + 2. IEEE, if OUTPUT-FORMAT is `IEEE' + + 3. COFF (the `coff-m68k' variant in BFD), if OUTPUT-FORMAT is + `COFF' + +`LIST ANYTHING...' + Print (to the standard output file) a link map, as produced by the + `ld' command-line option `-M'. + + The keyword `LIST' may be followed by anything on the same line, + with no change in its effect. + +`LOAD FILENAME' +`LOAD FILENAME, FILENAME, ... FILENAME' + Include one or more object file FILENAME in the link; this has the + same effect as specifying FILENAME directly on the `ld' command + line. + +`NAME OUTPUT-NAME' + OUTPUT-NAME is the name for the program produced by `ld'; the + MRI-compatible command `NAME' is equivalent to the command-line + option `-o' or the general script language command `OUTPUT'. + +`ORDER SECNAME, SECNAME, ... SECNAME' +`ORDER SECNAME SECNAME SECNAME' + Normally, `ld' orders the sections in its output file in the order + in which they first appear in the input files. In an + MRI-compatible script, you can override this ordering with the + `ORDER' command. The sections you list with `ORDER' will appear + first in your output file, in the order specified. + +`PUBLIC NAME=EXPRESSION' +`PUBLIC NAME,EXPRESSION' +`PUBLIC NAME EXPRESSION' + Supply a value (EXPRESSION) for external symbol NAME used in the + linker input files. + +`SECT SECNAME, EXPRESSION' +`SECT SECNAME=EXPRESSION' +`SECT SECNAME EXPRESSION' + You can use any of these three forms of the `SECT' command to + specify the start address (EXPRESSION) for section SECNAME. If + you have more than one `SECT' statement for the same SECNAME, only + the _first_ sets the start address. + + +File: ld.info, Node: GNU Free Documentation License, Next: LD Index, Prev: MRI, Up: Top + +Appendix B GNU Free Documentation License +***************************************** + + Version 1.1, March 2000 + + Copyright (C) 2000, 2003 Free Software Foundation, Inc. + 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + + 0. PREAMBLE + + The purpose of this License is to make a manual, textbook, or other + written document "free" in the sense of freedom: to assure everyone + the effective freedom to copy and redistribute it, with or without + modifying it, either commercially or noncommercially. Secondarily, + this License preserves for the author and publisher a way to get + credit for their work, while not being considered responsible for + modifications made by others. + + This License is a kind of "copyleft", which means that derivative + works of the document must themselves be free in the same sense. + It complements the GNU General Public License, which is a copyleft + license designed for free software. + + We have designed this License in order to use it for manuals for + free software, because free software needs free documentation: a + free program should come with manuals providing the same freedoms + that the software does. But this License is not limited to + software manuals; it can be used for any textual work, regardless + of subject matter or whether it is published as a printed book. + We recommend this License principally for works whose purpose is + instruction or reference. + + + 1. APPLICABILITY AND DEFINITIONS + + This License applies to any manual or other work that contains a + notice placed by the copyright holder saying it can be distributed + under the terms of this License. The "Document", below, refers to + any such manual or work. Any member of the public is a licensee, + and is addressed as "you." + + A "Modified Version" of the Document means any work containing the + Document or a portion of it, either copied verbatim, or with + modifications and/or translated into another language. + + A "Secondary Section" is a named appendix or a front-matter + section of the Document that deals exclusively with the + relationship of the publishers or authors of the Document to the + Document's overall subject (or to related matters) and contains + nothing that could fall directly within that overall subject. + (For example, if the Document is in part a textbook of + mathematics, a Secondary Section may not explain any mathematics.) + The relationship could be a matter of historical connection with + the subject or with related matters, or of legal, commercial, + philosophical, ethical or political position regarding them. + + The "Invariant Sections" are certain Secondary Sections whose + titles are designated, as being those of Invariant Sections, in + the notice that says that the Document is released under this + License. + + The "Cover Texts" are certain short passages of text that are + listed, as Front-Cover Texts or Back-Cover Texts, in the notice + that says that the Document is released under this License. + + A "Transparent" copy of the Document means a machine-readable copy, + represented in a format whose specification is available to the + general public, whose contents can be viewed and edited directly + and straightforwardly with generic text editors or (for images + composed of pixels) generic paint programs or (for drawings) some + widely available drawing editor, and that is suitable for input to + text formatters or for automatic translation to a variety of + formats suitable for input to text formatters. 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Include, immediately after the copyright notices, a license + notice giving the public permission to use the Modified Version + under the terms of this License, in the form shown in the + Addendum below. + G. Preserve in that license notice the full lists of Invariant + Sections and required Cover Texts given in the Document's + license notice. + H. Include an unaltered copy of this License. + I. Preserve the section entitled "History", and its title, and add + to it an item stating at least the title, year, new authors, and + publisher of the Modified Version as given on the Title Page. + If there is no section entitled "History" in the Document, + create one stating the title, year, authors, and publisher of + the Document as given on its Title Page, then add an item + describing the Modified Version as stated in the previous + sentence. + J. Preserve the network location, if any, given in the Document for + public access to a Transparent copy of the Document, and + likewise the network locations given in the Document for + previous versions it was based on. These may be placed in the + "History" section. You may omit a network location for a work + that was published at least four years before the Document + itself, or if the original publisher of the version it refers + to gives permission. + K. In any section entitled "Acknowledgements" or "Dedications", + preserve the section's title, and preserve in the section all the + substance and tone of each of the contributor acknowledgements + and/or dedications given therein. + L. Preserve all the Invariant Sections of the Document, + unaltered in their text and in their titles. Section numbers + or the equivalent are not considered part of the section titles. + M. Delete any section entitled "Endorsements." Such a section + may not be included in the Modified Version. + N. Do not retitle any existing section as "Endorsements" or to + conflict in title with any Invariant Section. + + If the Modified Version includes new front-matter sections or + appendices that qualify as Secondary Sections and contain no + material copied from the Document, you may at your option + designate some or all of these sections as invariant. To do this, + add their titles to the list of Invariant Sections in the Modified + Version's license notice. These titles must be distinct from any + other section titles. + + You may add a section entitled "Endorsements", provided it contains + nothing but endorsements of your Modified Version by various + parties-for example, statements of peer review or that the text has + been approved by an organization as the authoritative definition + of a standard. + + You may add a passage of up to five words as a Front-Cover Text, + and a passage of up to 25 words as a Back-Cover Text, to the end + of the list of Cover Texts in the Modified Version. Only one + passage of Front-Cover Text and one of Back-Cover Text may be + added by (or through arrangements made by) any one entity. If the + Document already includes a cover text for the same cover, + previously added by you or by arrangement made by the same entity + you are acting on behalf of, you may not add another; but you may + replace the old one, on explicit permission from the previous + publisher that added the old one. + + The author(s) and publisher(s) of the Document do not by this + License give permission to use their names for publicity for or to + assert or imply endorsement of any Modified Version. + + 5. COMBINING DOCUMENTS + + You may combine the Document with other documents released under + this License, under the terms defined in section 4 above for + modified versions, provided that you include in the combination + all of the Invariant Sections of all of the original documents, + unmodified, and list them all as Invariant Sections of your + combined work in its license notice. + + The combined work need only contain one copy of this License, and + multiple identical Invariant Sections may be replaced with a single + copy. If there are multiple Invariant Sections with the same name + but different contents, make the title of each such section unique + by adding at the end of it, in parentheses, the name of the + original author or publisher of that section if known, or else a + unique number. Make the same adjustment to the section titles in + the list of Invariant Sections in the license notice of the + combined work. + + In the combination, you must combine any sections entitled + "History" in the various original documents, forming one section + entitled "History"; likewise combine any sections entitled + "Acknowledgements", and any sections entitled "Dedications." You + must delete all sections entitled "Endorsements." + + 6. COLLECTIONS OF DOCUMENTS + + You may make a collection consisting of the Document and other + documents released under this License, and replace the individual + copies of this License in the various documents with a single copy + that is included in the collection, provided that you follow the + rules of this License for verbatim copying of each of the + documents in all other respects. + + You may extract a single document from such a collection, and + distribute it individually under this License, provided you insert + a copy of this License into the extracted document, and follow + this License in all other respects regarding verbatim copying of + that document. + + 7. AGGREGATION WITH INDEPENDENT WORKS + + A compilation of the Document or its derivatives with other + separate and independent documents or works, in or on a volume of + a storage or distribution medium, does not as a whole count as a + Modified Version of the Document, provided no compilation + copyright is claimed for the compilation. Such a compilation is + called an "aggregate", and this License does not apply to the + other self-contained works thus compiled with the Document, on + account of their being thus compiled, if they are not themselves + derivative works of the Document. + + If the Cover Text requirement of section 3 is applicable to these + copies of the Document, then if the Document is less than one + quarter of the entire aggregate, the Document's Cover Texts may be + placed on covers that surround only the Document within the + aggregate. Otherwise they must appear on covers around the whole + aggregate. + + 8. TRANSLATION + + Translation is considered a kind of modification, so you may + distribute translations of the Document under the terms of section + 4. Replacing Invariant Sections with translations requires special + permission from their copyright holders, but you may include + translations of some or all Invariant Sections in addition to the + original versions of these Invariant Sections. You may include a + translation of this License provided that you also include the + original English version of this License. In case of a + disagreement between the translation and the original English + version of this License, the original English version will prevail. + + 9. TERMINATION + + You may not copy, modify, sublicense, or distribute the Document + except as expressly provided for under this License. Any other + attempt to copy, modify, sublicense or distribute the Document is + void, and will automatically terminate your rights under this + License. However, parties who have received copies, or rights, + from you under this License will not have their licenses + terminated so long as such parties remain in full compliance. + + 10. FUTURE REVISIONS OF THIS LICENSE + + The Free Software Foundation may publish new, revised versions of + the GNU Free Documentation License from time to time. Such new + versions will be similar in spirit to the present version, but may + differ in detail to address new problems or concerns. See + http://www.gnu.org/copyleft/. + + Each version of the License is given a distinguishing version + number. If the Document specifies that a particular numbered + version of this License "or any later version" applies to it, you + have the option of following the terms and conditions either of + that specified version or of any later version that has been + published (not as a draft) by the Free Software Foundation. If + the Document does not specify a version number of this License, + you may choose any version ever published (not as a draft) by the + Free Software Foundation. + + +ADDENDUM: How to use this License for your documents +==================================================== + +To use this License in a document you have written, include a copy of +the License in the document and put the following copyright and license +notices just after the title page: + + Copyright (C) YEAR YOUR NAME. + Permission is granted to copy, distribute and/or modify this document + under the terms of the GNU Free Documentation License, Version 1.1 + or any later version published by the Free Software Foundation; + with the Invariant Sections being LIST THEIR TITLES, with the + Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST. + A copy of the license is included in the section entitled "GNU + Free Documentation License." + + If you have no Invariant Sections, write "with no Invariant Sections" +instead of saying which ones are invariant. If you have no Front-Cover +Texts, write "no Front-Cover Texts" instead of "Front-Cover Texts being +LIST"; likewise for Back-Cover Texts. + + If your document contains nontrivial examples of program code, we +recommend releasing these examples in parallel under your choice of +free software license, such as the GNU General Public License, to +permit their use in free software. + + +File: ld.info, Node: LD Index, Prev: GNU Free Documentation License, Up: Top + +LD Index +******** + + +* Menu: + +* ": Symbols. (line 6) +* -(: Options. (line 675) +* --accept-unknown-input-arch: Options. (line 693) +* --add-needed: Options. (line 717) +* --add-stdcall-alias: Options. (line 1527) +* --allow-multiple-definition: Options. (line 945) +* --allow-shlib-undefined: Options. (line 951) +* --architecture=ARCH: Options. (line 113) +* --as-needed: Options. (line 703) +* --auxiliary=NAME: Options. (line 235) +* --bank-window: Options. (line 1926) +* --base-file: Options. (line 1532) +* --be8: ARM. (line 28) +* --bss-plt: PowerPC ELF32. (line 16) +* --build-id: Options. (line 1489) +* --build-id=STYLE: Options. (line 1489) +* --check-sections: Options. (line 799) +* --cref: Options. (line 811) +* --default-imported-symver: Options. (line 988) +* --default-script=SCRIPT: Options. (line 520) +* --default-symver: Options. (line 984) +* --defsym=SYMBOL=EXP: Options. (line 839) +* --demangle[=STYLE]: Options. (line 852) +* --disable-auto-image-base: Options. (line 1701) +* --disable-auto-import: Options. (line 1836) +* --disable-long-section-names: Options. (line 1542) +* --disable-new-dtags: Options. (line 1452) +* --disable-runtime-pseudo-reloc: Options. (line 1849) +* --disable-stdcall-fixup: Options. (line 1564) +* --discard-all: Options. (line 566) +* --discard-locals: Options. (line 570) +* --dll: Options. (line 1537) +* --dll-search-prefix: Options. (line 1707) +* --dotsyms: PowerPC64 ELF64. (line 33) +* --dynamic-linker=FILE: Options. (line 865) +* --dynamic-list-cpp-new: Options. (line 791) +* --dynamic-list-cpp-typeinfo: Options. (line 795) +* --dynamic-list-data: Options. (line 788) +* --dynamic-list=DYNAMIC-LIST-FILE: Options. (line 775) +* --dynamicbase: Options. (line 1885) +* --eh-frame-hdr: Options. (line 1448) +* --emit-relocs: Options. (line 455) +* --emit-stack-syms: SPU ELF. (line 46) +* --emit-stub-syms <1>: PowerPC ELF32. (line 47) +* --emit-stub-syms <2>: SPU ELF. (line 15) +* --emit-stub-syms: PowerPC64 ELF64. (line 29) +* --enable-auto-image-base: Options. (line 1693) +* --enable-auto-import: Options. (line 1716) +* --enable-extra-pe-debug: Options. (line 1854) +* --enable-long-section-names: Options. (line 1542) +* --enable-new-dtags: Options. (line 1452) +* --enable-runtime-pseudo-reloc: Options. (line 1841) +* --enable-stdcall-fixup: Options. (line 1564) +* --entry=ENTRY: Options. (line 167) +* --error-unresolved-symbols: Options. (line 1401) +* --exclude-libs: Options. (line 177) +* --exclude-modules-for-implib: Options. (line 188) +* --exclude-symbols: Options. (line 1606) +* --export-all-symbols: Options. (line 1582) +* --export-dynamic: Options. (line 201) +* --extra-overlay-stubs: SPU ELF. (line 19) +* --fatal-warnings: Options. (line 872) +* --file-alignment: Options. (line 1612) +* --filter=NAME: Options. (line 256) +* --fix-cortex-a8: i960. (line 39) +* --fix-v4bx: ARM. (line 49) +* --fix-v4bx-interworking: ARM. (line 62) +* --force-dynamic: Options. (line 464) +* --force-exe-suffix: Options. (line 877) +* --forceinteg: Options. (line 1890) +* --format=FORMAT: Options. (line 124) +* --format=VERSION: TI COFF. (line 6) +* --gc-sections: Options. (line 887) +* --got: Options. (line 1939) +* --got=TYPE: M68K. (line 6) +* --gpsize=VALUE: Options. (line 289) +* --hash-size=NUMBER: Options. (line 1461) +* --hash-style=STYLE: Options. (line 1469) +* --heap: Options. (line 1618) +* --help: Options. (line 918) +* --image-base: Options. (line 1625) +* --just-symbols=FILE: Options. (line 487) +* --kill-at: Options. (line 1634) +* --large-address-aware: Options. (line 1639) +* --library-path=DIR: Options. (line 348) +* --library=NAMESPEC: Options. (line 315) +* --local-store=lo:hi: SPU ELF. (line 24) +* --major-image-version: Options. (line 1648) +* --major-os-version: Options. (line 1653) +* --major-subsystem-version: Options. (line 1657) +* --minor-image-version: Options. (line 1662) +* --minor-os-version: Options. (line 1667) +* --minor-subsystem-version: Options. (line 1671) +* --mri-script=MRI-CMDFILE: Options. (line 148) +* --multi-subspace: HPPA ELF32. (line 6) +* --nmagic: Options. (line 419) +* --no-accept-unknown-input-arch: Options. (line 693) +* --no-add-needed: Options. (line 717) +* --no-allow-shlib-undefined: Options. (line 951) +* --no-as-needed: Options. (line 703) +* --no-bind: Options. (line 1904) +* --no-check-sections: Options. (line 799) +* --no-define-common: Options. (line 823) +* --no-demangle: Options. (line 852) +* --no-dotsyms: PowerPC64 ELF64. (line 33) +* --no-enum-size-warning: ARM. (line 111) +* --no-export-dynamic: Options. (line 201) +* --no-fatal-warnings: Options. (line 872) +* --no-fix-cortex-a8: i960. (line 39) +* --no-gc-sections: Options. (line 887) +* --no-isolation: Options. (line 1897) +* --no-keep-memory: Options. (line 930) +* --no-multi-toc: PowerPC64 ELF64. (line 74) +* --no-omagic: Options. (line 433) +* --no-opd-optimize: PowerPC64 ELF64. (line 48) +* --no-overlays: SPU ELF. (line 9) +* --no-print-gc-sections: Options. (line 909) +* --no-relax: Xtensa. (line 56) +* --no-seh: Options. (line 1900) +* --no-tls-optimize <1>: PowerPC ELF32. (line 51) +* --no-tls-optimize: PowerPC64 ELF64. (line 43) +* --no-toc-optimize: PowerPC64 ELF64. (line 60) +* --no-trampoline: Options. (line 1920) +* --no-undefined: Options. (line 937) +* --no-undefined-version: Options. (line 979) +* --no-warn-mismatch: Options. (line 992) +* --no-warn-search-mismatch: Options. (line 1001) +* --no-wchar-size-warning: ARM. (line 118) +* --no-whole-archive: Options. (line 1005) +* --noinhibit-exec: Options. (line 1009) +* --non-overlapping-opd: PowerPC64 ELF64. (line 54) +* --nxcompat: Options. (line 1893) +* --oformat=OUTPUT-FORMAT: Options. (line 1021) +* --omagic: Options. (line 424) +* --out-implib: Options. (line 1684) +* --output-def: Options. (line 1676) +* --output=OUTPUT: Options. (line 439) +* --pic-executable: Options. (line 1034) +* --pic-veneer: ARM. (line 124) +* --plugin: SPU ELF. (line 6) +* --print-gc-sections: Options. (line 909) +* --print-map: Options. (line 382) +* --reduce-memory-overheads: Options. (line 1475) +* --relax: Options. (line 1050) +* --relax on i960: i960. (line 31) +* --relax on PowerPC: PowerPC ELF32. (line 6) +* --relax on Xtensa: Xtensa. (line 27) +* --relocatable: Options. (line 468) +* --retain-symbols-file=FILENAME: Options. (line 1071) +* --script=SCRIPT: Options. (line 511) +* --sdata-got: PowerPC ELF32. (line 33) +* --section-alignment: Options. (line 1859) +* --section-start=SECTIONNAME=ORG: Options. (line 1227) +* --secure-plt: PowerPC ELF32. (line 26) +* --sort-common: Options. (line 1169) +* --sort-section=alignment: Options. (line 1184) +* --sort-section=name: Options. (line 1180) +* --split-by-file: Options. (line 1188) +* --split-by-reloc: Options. (line 1193) +* --stack: Options. (line 1865) +* --stack-analysis: SPU ELF. (line 29) +* --stats: Options. (line 1206) +* --strip-all: Options. (line 498) +* --strip-debug: Options. (line 502) +* --stub-group-size: PowerPC64 ELF64. (line 6) +* --stub-group-size=N <1>: ARM. (line 129) +* --stub-group-size=N: HPPA ELF32. (line 12) +* --subsystem: Options. (line 1872) +* --support-old-code: ARM. (line 6) +* --sysroot=DIRECTORY: Options. (line 1210) +* --target-help: Options. (line 922) +* --target1-abs: ARM. (line 32) +* --target1-rel: ARM. (line 32) +* --target2=TYPE: ARM. (line 37) +* --thumb-entry=ENTRY: ARM. (line 17) +* --trace: Options. (line 507) +* --trace-symbol=SYMBOL: Options. (line 576) +* --traditional-format: Options. (line 1215) +* --tsaware: Options. (line 1910) +* --undefined=SYMBOL: Options. (line 533) +* --unique[=SECTION]: Options. (line 551) +* --unresolved-symbols: Options. (line 1246) +* --use-blx: ARM. (line 74) +* --use-nul-prefixed-import-tables: ARM. (line 23) +* --verbose: Options. (line 1275) +* --version: Options. (line 560) +* --version-script=VERSION-SCRIPTFILE: Options. (line 1281) +* --vfp11-denorm-fix: ARM. (line 83) +* --warn-alternate-em: Options. (line 1393) +* --warn-common: Options. (line 1292) +* --warn-constructors: Options. (line 1360) +* --warn-multiple-gp: Options. (line 1365) +* --warn-once: Options. (line 1379) +* --warn-section-align: Options. (line 1383) +* --warn-shared-textrel: Options. (line 1390) +* --warn-unresolved-symbols: Options. (line 1396) +* --wdmdriver: Options. (line 1907) +* --whole-archive: Options. (line 1405) +* --wrap=SYMBOL: Options. (line 1419) +* -A ARCH: Options. (line 112) +* -a KEYWORD: Options. (line 105) +* -assert KEYWORD: Options. (line 727) +* -b FORMAT: Options. (line 124) +* -Bdynamic: Options. (line 730) +* -Bgroup: Options. (line 740) +* -Bshareable: Options. (line 1162) +* -Bstatic: Options. (line 747) +* -Bsymbolic: Options. (line 762) +* -Bsymbolic-functions: Options. (line 769) +* -c MRI-CMDFILE: Options. (line 148) +* -call_shared: Options. (line 730) +* -d: Options. (line 158) +* -dc: Options. (line 158) +* -dn: Options. (line 747) +* -dp: Options. (line 158) +* -dT SCRIPT: Options. (line 520) +* -dy: Options. (line 730) +* -E: Options. (line 201) +* -e ENTRY: Options. (line 167) +* -EB: Options. (line 228) +* -EL: Options. (line 231) +* -F NAME: Options. (line 256) +* -f NAME: Options. (line 235) +* -fini=NAME: Options. (line 280) +* -g: Options. (line 286) +* -G VALUE: Options. (line 289) +* -h NAME: Options. (line 297) +* -i: Options. (line 306) +* -IFILE: Options. (line 865) +* -init=NAME: Options. (line 309) +* -L DIR: Options. (line 348) +* -l NAMESPEC: Options. (line 315) +* -M: Options. (line 382) +* -m EMULATION: Options. (line 372) +* -Map=MAPFILE: Options. (line 926) +* -N: Options. (line 424) +* -n: Options. (line 419) +* -non_shared: Options. (line 747) +* -nostdlib: Options. (line 1015) +* -O LEVEL: Options. (line 445) +* -o OUTPUT: Options. (line 439) +* -pie: Options. (line 1034) +* -q: Options. (line 455) +* -qmagic: Options. (line 1044) +* -Qy: Options. (line 1047) +* -r: Options. (line 468) +* -R FILE: Options. (line 487) +* -rpath-link=DIR: Options. (line 1107) +* -rpath=DIR: Options. (line 1085) +* -s: Options. (line 498) +* -S: Options. (line 502) +* -shared: Options. (line 1162) +* -soname=NAME: Options. (line 297) +* -static: Options. (line 747) +* -t: Options. (line 507) +* -T SCRIPT: Options. (line 511) +* -Tbss=ORG: Options. (line 1236) +* -Tdata=ORG: Options. (line 1236) +* -Ttext-segment=ORG: Options. (line 1242) +* -Ttext=ORG: Options. (line 1236) +* -u SYMBOL: Options. (line 533) +* -Ur: Options. (line 541) +* -V: Options. (line 560) +* -v: Options. (line 560) +* -X: Options. (line 570) +* -x: Options. (line 566) +* -Y PATH: Options. (line 585) +* -y SYMBOL: Options. (line 576) +* -z defs: Options. (line 937) +* -z KEYWORD: Options. (line 589) +* -z muldefs: Options. (line 945) +* .: Location Counter. (line 6) +* /DISCARD/: Output Section Discarding. + (line 21) +* :PHDR: Output Section Phdr. + (line 6) +* =FILLEXP: Output Section Fill. + (line 6) +* >REGION: Output Section Region. + (line 6) +* [COMMON]: Input Section Common. + (line 29) +* ABSOLUTE (MRI): MRI. (line 33) +* absolute and relocatable symbols: Expression Section. (line 6) +* absolute expressions: Expression Section. (line 6) +* ABSOLUTE(EXP): Builtin Functions. (line 10) +* ADDR(SECTION): Builtin Functions. (line 17) +* address, section: Output Section Address. + (line 6) +* ALIAS (MRI): MRI. (line 44) +* ALIGN (MRI): MRI. (line 50) +* align expression: Builtin Functions. (line 36) +* align location counter: Builtin Functions. (line 36) +* ALIGN(ALIGN): Builtin Functions. (line 36) +* ALIGN(EXP,ALIGN): Builtin Functions. (line 36) +* ALIGN(SECTION_ALIGN): Forced Output Alignment. + (line 6) +* aligned common symbols: WIN32. (line 418) +* ALIGNOF(SECTION): Builtin Functions. (line 62) +* allocating memory: MEMORY. (line 6) +* architecture: Miscellaneous Commands. + (line 72) +* architectures: Options. (line 112) +* archive files, from cmd line: Options. (line 315) +* archive search path in linker script: File Commands. (line 74) +* arithmetic: Expressions. (line 6) +* arithmetic operators: Operators. (line 6) +* ARM interworking support: ARM. (line 6) +* AS_NEEDED(FILES): File Commands. (line 54) +* ASSERT: Miscellaneous Commands. + (line 9) +* assertion in linker script: Miscellaneous Commands. + (line 9) +* assignment in scripts: Assignments. (line 6) +* AT(LMA): Output Section LMA. (line 6) +* AT>LMA_REGION: Output Section LMA. (line 6) +* automatic data imports: WIN32. (line 185) +* back end: BFD. (line 6) +* BASE (MRI): MRI. (line 54) +* BE8: ARM. (line 28) +* BFD canonical format: Canonical format. (line 11) +* BFD requirements: BFD. (line 16) +* big-endian objects: Options. (line 228) +* binary input format: Options. (line 124) +* BLOCK(EXP): Builtin Functions. (line 75) +* bug criteria: Bug Criteria. (line 6) +* bug reports: Bug Reporting. (line 6) +* bugs in ld: Reporting Bugs. (line 6) +* BYTE(EXPRESSION): Output Section Data. + (line 6) +* C++ constructors, arranging in link: Output Section Keywords. + (line 19) +* CHIP (MRI): MRI. (line 58) +* COLLECT_NO_DEMANGLE: Environment. (line 29) +* combining symbols, warnings on: Options. (line 1292) +* command files: Scripts. (line 6) +* command line: Options. (line 6) +* common allocation: Options. (line 158) +* common allocation in linker script: Miscellaneous Commands. + (line 20) +* common symbol placement: Input Section Common. + (line 6) +* COMMONPAGESIZE: Symbolic Constants. (line 13) +* compatibility, MRI: Options. (line 148) +* CONSTANT: Symbolic Constants. (line 6) +* constants in linker scripts: Constants. (line 6) +* constraints on output sections: Output Section Constraint. + (line 6) +* CONSTRUCTORS: Output Section Keywords. + (line 19) +* constructors: Options. (line 541) +* constructors, arranging in link: Output Section Keywords. + (line 19) +* Cortex-A8 erratum workaround: i960. (line 39) +* crash of linker: Bug Criteria. (line 9) +* CREATE_OBJECT_SYMBOLS: Output Section Keywords. + (line 9) +* creating a DEF file: WIN32. (line 152) +* cross reference table: Options. (line 811) +* cross references: Miscellaneous Commands. + (line 56) +* current output location: Location Counter. (line 6) +* data: Output Section Data. + (line 6) +* DATA_SEGMENT_ALIGN(MAXPAGESIZE, COMMONPAGESIZE): Builtin Functions. + (line 80) +* DATA_SEGMENT_END(EXP): Builtin Functions. (line 101) +* DATA_SEGMENT_RELRO_END(OFFSET, EXP): Builtin Functions. (line 107) +* dbx: Options. (line 1220) +* DEF files, creating: Options. (line 1676) +* default emulation: Environment. (line 21) +* default input format: Environment. (line 9) +* DEFINED(SYMBOL): Builtin Functions. (line 118) +* deleting local symbols: Options. (line 566) +* demangling, default: Environment. (line 29) +* demangling, from command line: Options. (line 852) +* direct linking to a dll: WIN32. (line 233) +* discarding sections: Output Section Discarding. + (line 6) +* discontinuous memory: MEMORY. (line 6) +* DLLs, creating: Options. (line 1676) +* DLLs, linking to: Options. (line 1707) +* dot: Location Counter. (line 6) +* dot inside sections: Location Counter. (line 36) +* dot outside sections: Location Counter. (line 66) +* dynamic linker, from command line: Options. (line 865) +* dynamic symbol table: Options. (line 201) +* ELF program headers: PHDRS. (line 6) +* emulation: Options. (line 372) +* emulation, default: Environment. (line 21) +* END (MRI): MRI. (line 62) +* endianness: Options. (line 228) +* entry point: Entry Point. (line 6) +* entry point, from command line: Options. (line 167) +* entry point, thumb: ARM. (line 17) +* ENTRY(SYMBOL): Entry Point. (line 6) +* error on valid input: Bug Criteria. (line 12) +* example of linker script: Simple Example. (line 6) +* exporting DLL symbols: WIN32. (line 19) +* expression evaluation order: Evaluation. (line 6) +* expression sections: Expression Section. (line 6) +* expression, absolute: Builtin Functions. (line 10) +* expressions: Expressions. (line 6) +* EXTERN: Miscellaneous Commands. + (line 13) +* fatal signal: Bug Criteria. (line 9) +* file name wildcard patterns: Input Section Wildcards. + (line 6) +* FILEHDR: PHDRS. (line 61) +* filename symbols: Output Section Keywords. + (line 9) +* fill pattern, entire section: Output Section Fill. + (line 6) +* FILL(EXPRESSION): Output Section Data. + (line 39) +* finalization function: Options. (line 280) +* first input file: File Commands. (line 82) +* first instruction: Entry Point. (line 6) +* FIX_V4BX: ARM. (line 49) +* FIX_V4BX_INTERWORKING: ARM. (line 62) +* FORCE_COMMON_ALLOCATION: Miscellaneous Commands. + (line 20) +* forcing input section alignment: Forced Input Alignment. + (line 6) +* forcing output section alignment: Forced Output Alignment. + (line 6) +* forcing the creation of dynamic sections: Options. (line 464) +* FORMAT (MRI): MRI. (line 66) +* functions in expressions: Builtin Functions. (line 6) +* garbage collection <1>: Options. (line 909) +* garbage collection <2>: Input Section Keep. (line 6) +* garbage collection: Options. (line 887) +* generating optimized output: Options. (line 445) +* GNU linker: Overview. (line 6) +* GNUTARGET: Environment. (line 9) +* GROUP(FILES): File Commands. (line 47) +* grouping input files: File Commands. (line 47) +* groups of archives: Options. (line 675) +* H8/300 support: H8/300. (line 6) +* header size: Builtin Functions. (line 183) +* heap size: Options. (line 1618) +* help: Options. (line 918) +* holes: Location Counter. (line 12) +* holes, filling: Output Section Data. + (line 39) +* HPPA multiple sub-space stubs: HPPA ELF32. (line 6) +* HPPA stub grouping: HPPA ELF32. (line 12) +* i960 support: i960. (line 6) +* image base: Options. (line 1625) +* implicit linker scripts: Implicit Linker Scripts. + (line 6) +* import libraries: WIN32. (line 10) +* INCLUDE FILENAME: File Commands. (line 9) +* including a linker script: File Commands. (line 9) +* including an entire archive: Options. (line 1405) +* incremental link: Options. (line 306) +* INHIBIT_COMMON_ALLOCATION: Miscellaneous Commands. + (line 25) +* initialization function: Options. (line 309) +* initialized data in ROM: Output Section LMA. (line 26) +* input file format in linker script: Format Commands. (line 35) +* input filename symbols: Output Section Keywords. + (line 9) +* input files in linker scripts: File Commands. (line 19) +* input files, displaying: Options. (line 507) +* input format: Options. (line 124) +* input object files in linker scripts: File Commands. (line 19) +* input section alignment: Forced Input Alignment. + (line 6) +* input section basics: Input Section Basics. + (line 6) +* input section wildcards: Input Section Wildcards. + (line 6) +* input sections: Input Section. (line 6) +* INPUT(FILES): File Commands. (line 19) +* INSERT: Miscellaneous Commands. + (line 30) +* insert user script into default script: Miscellaneous Commands. + (line 30) +* integer notation: Constants. (line 6) +* integer suffixes: Constants. (line 15) +* internal object-file format: Canonical format. (line 11) +* invalid input: Bug Criteria. (line 14) +* K and M integer suffixes: Constants. (line 15) +* KEEP: Input Section Keep. (line 6) +* l =: MEMORY. (line 74) +* lazy evaluation: Evaluation. (line 6) +* ld bugs, reporting: Bug Reporting. (line 6) +* LDEMULATION: Environment. (line 21) +* len =: MEMORY. (line 74) +* LENGTH =: MEMORY. (line 74) +* LENGTH(MEMORY): Builtin Functions. (line 135) +* library search path in linker script: File Commands. (line 74) +* link map: Options. (line 382) +* link-time runtime library search path: Options. (line 1107) +* linker crash: Bug Criteria. (line 9) +* linker script concepts: Basic Script Concepts. + (line 6) +* linker script example: Simple Example. (line 6) +* linker script file commands: File Commands. (line 6) +* linker script format: Script Format. (line 6) +* linker script input object files: File Commands. (line 19) +* linker script simple commands: Simple Commands. (line 6) +* linker scripts: Scripts. (line 6) +* LIST (MRI): MRI. (line 77) +* little-endian objects: Options. (line 231) +* LOAD (MRI): MRI. (line 84) +* load address: Output Section LMA. (line 6) +* LOADADDR(SECTION): Builtin Functions. (line 138) +* loading, preventing: Output Section Type. + (line 22) +* local symbols, deleting: Options. (line 570) +* location counter: Location Counter. (line 6) +* LONG(EXPRESSION): Output Section Data. + (line 6) +* M and K integer suffixes: Constants. (line 15) +* M68HC11 and 68HC12 support: M68HC11/68HC12. (line 6) +* machine architecture: Miscellaneous Commands. + (line 72) +* machine dependencies: Machine Dependent. (line 6) +* mapping input sections to output sections: Input Section. (line 6) +* MAX: Builtin Functions. (line 143) +* MAXPAGESIZE: Symbolic Constants. (line 10) +* MEMORY: MEMORY. (line 6) +* memory region attributes: MEMORY. (line 34) +* memory regions: MEMORY. (line 6) +* memory regions and sections: Output Section Region. + (line 6) +* memory usage: Options. (line 930) +* MIN: Builtin Functions. (line 146) +* Motorola 68K GOT generation: M68K. (line 6) +* MRI compatibility: MRI. (line 6) +* MSP430 extra sections: MSP430. (line 11) +* NAME (MRI): MRI. (line 90) +* name, section: Output Section Name. + (line 6) +* names: Symbols. (line 6) +* naming the output file: Options. (line 439) +* NEXT(EXP): Builtin Functions. (line 150) +* NMAGIC: Options. (line 419) +* NO_ENUM_SIZE_WARNING: ARM. (line 111) +* NO_WCHAR_SIZE_WARNING: ARM. (line 118) +* NOCROSSREFS(SECTIONS): Miscellaneous Commands. + (line 56) +* NOLOAD: Output Section Type. + (line 22) +* not enough room for program headers: Builtin Functions. (line 188) +* o =: MEMORY. (line 69) +* objdump -i: BFD. (line 6) +* object file management: BFD. (line 6) +* object files: Options. (line 29) +* object formats available: BFD. (line 6) +* object size: Options. (line 289) +* OMAGIC: Options. (line 424) +* ONLY_IF_RO: Output Section Constraint. + (line 6) +* ONLY_IF_RW: Output Section Constraint. + (line 6) +* opening object files: BFD outline. (line 6) +* operators for arithmetic: Operators. (line 6) +* options: Options. (line 6) +* ORDER (MRI): MRI. (line 95) +* org =: MEMORY. (line 69) +* ORIGIN =: MEMORY. (line 69) +* ORIGIN(MEMORY): Builtin Functions. (line 156) +* orphan: Orphan Sections. (line 6) +* output file after errors: Options. (line 1009) +* output file format in linker script: Format Commands. (line 10) +* output file name in linker script: File Commands. (line 64) +* output section alignment: Forced Output Alignment. + (line 6) +* output section attributes: Output Section Attributes. + (line 6) +* output section data: Output Section Data. + (line 6) +* OUTPUT(FILENAME): File Commands. (line 64) +* OUTPUT_ARCH(BFDARCH): Miscellaneous Commands. + (line 72) +* OUTPUT_FORMAT(BFDNAME): Format Commands. (line 10) +* OVERLAY: Overlay Description. + (line 6) +* overlays: Overlay Description. + (line 6) +* partial link: Options. (line 468) +* PE import table prefixing: ARM. (line 23) +* PHDRS: PHDRS. (line 61) +* PIC_VENEER: ARM. (line 124) +* position independent executables: Options. (line 1036) +* PowerPC ELF32 options: PowerPC ELF32. (line 16) +* PowerPC GOT: PowerPC ELF32. (line 33) +* PowerPC long branches: PowerPC ELF32. (line 6) +* PowerPC PLT: PowerPC ELF32. (line 16) +* PowerPC stub symbols: PowerPC ELF32. (line 47) +* PowerPC TLS optimization: PowerPC ELF32. (line 51) +* PowerPC64 dot symbols: PowerPC64 ELF64. (line 33) +* PowerPC64 ELF64 options: PowerPC64 ELF64. (line 6) +* PowerPC64 multi-TOC: PowerPC64 ELF64. (line 74) +* PowerPC64 OPD optimization: PowerPC64 ELF64. (line 48) +* PowerPC64 OPD spacing: PowerPC64 ELF64. (line 54) +* PowerPC64 stub grouping: PowerPC64 ELF64. (line 6) +* PowerPC64 stub symbols: PowerPC64 ELF64. (line 29) +* PowerPC64 TLS optimization: PowerPC64 ELF64. (line 43) +* PowerPC64 TOC optimization: PowerPC64 ELF64. (line 60) +* precedence in expressions: Operators. (line 6) +* prevent unnecessary loading: Output Section Type. + (line 22) +* program headers: PHDRS. (line 6) +* program headers and sections: Output Section Phdr. + (line 6) +* program headers, not enough room: Builtin Functions. (line 188) +* program segments: PHDRS. (line 6) +* PROVIDE: PROVIDE. (line 6) +* PROVIDE_HIDDEN: PROVIDE_HIDDEN. (line 6) +* PUBLIC (MRI): MRI. (line 103) +* QUAD(EXPRESSION): Output Section Data. + (line 6) +* quoted symbol names: Symbols. (line 6) +* read-only text: Options. (line 419) +* read/write from cmd line: Options. (line 424) +* region alias: REGION_ALIAS. (line 6) +* region names: REGION_ALIAS. (line 6) +* REGION_ALIAS(ALIAS, REGION): REGION_ALIAS. (line 6) +* regions of memory: MEMORY. (line 6) +* relative expressions: Expression Section. (line 6) +* relaxing addressing modes: Options. (line 1050) +* relaxing on H8/300: H8/300. (line 9) +* relaxing on i960: i960. (line 31) +* relaxing on M68HC11: M68HC11/68HC12. (line 12) +* relaxing on Xtensa: Xtensa. (line 27) +* relocatable and absolute symbols: Expression Section. (line 6) +* relocatable output: Options. (line 468) +* removing sections: Output Section Discarding. + (line 6) +* reporting bugs in ld: Reporting Bugs. (line 6) +* requirements for BFD: BFD. (line 16) +* retain relocations in final executable: Options. (line 455) +* retaining specified symbols: Options. (line 1071) +* ROM initialized data: Output Section LMA. (line 26) +* round up expression: Builtin Functions. (line 36) +* round up location counter: Builtin Functions. (line 36) +* runtime library name: Options. (line 297) +* runtime library search path: Options. (line 1085) +* runtime pseudo-relocation: WIN32. (line 211) +* scaled integers: Constants. (line 15) +* scommon section: Input Section Common. + (line 20) +* script files: Options. (line 520) +* scripts: Scripts. (line 6) +* search directory, from cmd line: Options. (line 348) +* search path in linker script: File Commands. (line 74) +* SEARCH_DIR(PATH): File Commands. (line 74) +* SECT (MRI): MRI. (line 109) +* section address: Output Section Address. + (line 6) +* section address in expression: Builtin Functions. (line 17) +* section alignment: Builtin Functions. (line 62) +* section alignment, warnings on: Options. (line 1383) +* section data: Output Section Data. + (line 6) +* section fill pattern: Output Section Fill. + (line 6) +* section load address: Output Section LMA. (line 6) +* section load address in expression: Builtin Functions. (line 138) +* section name: Output Section Name. + (line 6) +* section name wildcard patterns: Input Section Wildcards. + (line 6) +* section size: Builtin Functions. (line 167) +* section, assigning to memory region: Output Section Region. + (line 6) +* section, assigning to program header: Output Section Phdr. + (line 6) +* SECTIONS: SECTIONS. (line 6) +* sections, discarding: Output Section Discarding. + (line 6) +* segment origins, cmd line: Options. (line 1236) +* SEGMENT_START(SEGMENT, DEFAULT): Builtin Functions. (line 159) +* segments, ELF: PHDRS. (line 6) +* shared libraries: Options. (line 1164) +* SHORT(EXPRESSION): Output Section Data. + (line 6) +* SIZEOF(SECTION): Builtin Functions. (line 167) +* SIZEOF_HEADERS: Builtin Functions. (line 183) +* small common symbols: Input Section Common. + (line 20) +* SORT: Input Section Wildcards. + (line 58) +* SORT_BY_ALIGNMENT: Input Section Wildcards. + (line 54) +* SORT_BY_NAME: Input Section Wildcards. + (line 46) +* SPU: SPU ELF. (line 29) +* SPU ELF options: SPU ELF. (line 6) +* SPU extra overlay stubs: SPU ELF. (line 19) +* SPU local store size: SPU ELF. (line 24) +* SPU overlay stub symbols: SPU ELF. (line 15) +* SPU overlays: SPU ELF. (line 9) +* SPU plugins: SPU ELF. (line 6) +* SQUAD(EXPRESSION): Output Section Data. + (line 6) +* stack size: Options. (line 1865) +* standard Unix system: Options. (line 7) +* start of execution: Entry Point. (line 6) +* STARTUP(FILENAME): File Commands. (line 82) +* strip all symbols: Options. (line 498) +* strip debugger symbols: Options. (line 502) +* stripping all but some symbols: Options. (line 1071) +* STUB_GROUP_SIZE: ARM. (line 129) +* SUBALIGN(SUBSECTION_ALIGN): Forced Input Alignment. + (line 6) +* suffixes for integers: Constants. (line 15) +* symbol defaults: Builtin Functions. (line 118) +* symbol definition, scripts: Assignments. (line 6) +* symbol names: Symbols. (line 6) +* symbol tracing: Options. (line 576) +* symbol versions: VERSION. (line 6) +* symbol-only input: Options. (line 487) +* symbolic constants: Symbolic Constants. (line 6) +* symbols, from command line: Options. (line 839) +* symbols, relocatable and absolute: Expression Section. (line 6) +* symbols, retaining selectively: Options. (line 1071) +* synthesizing linker: Options. (line 1050) +* synthesizing on H8/300: H8/300. (line 14) +* TARGET(BFDNAME): Format Commands. (line 35) +* TARGET1: ARM. (line 32) +* TARGET2: ARM. (line 37) +* text segment origin, cmd line: Options. (line 1243) +* thumb entry point: ARM. (line 17) +* TI COFF versions: TI COFF. (line 6) +* traditional format: Options. (line 1215) +* trampoline generation on M68HC11: M68HC11/68HC12. (line 31) +* trampoline generation on M68HC12: M68HC11/68HC12. (line 31) +* unallocated address, next: Builtin Functions. (line 150) +* undefined symbol: Options. (line 533) +* undefined symbol in linker script: Miscellaneous Commands. + (line 13) +* undefined symbols, warnings on: Options. (line 1379) +* uninitialized data placement: Input Section Common. + (line 6) +* unspecified memory: Output Section Data. + (line 39) +* usage: Options. (line 918) +* USE_BLX: ARM. (line 74) +* using a DEF file: WIN32. (line 57) +* using auto-export functionality: WIN32. (line 22) +* Using decorations: WIN32. (line 156) +* variables, defining: Assignments. (line 6) +* verbose: Options. (line 1275) +* version: Options. (line 560) +* version script: VERSION. (line 6) +* version script, symbol versions: Options. (line 1281) +* VERSION {script text}: VERSION. (line 6) +* versions of symbols: VERSION. (line 6) +* VFP11_DENORM_FIX: ARM. (line 83) +* warnings, on combining symbols: Options. (line 1292) +* warnings, on section alignment: Options. (line 1383) +* warnings, on undefined symbols: Options. (line 1379) +* weak externals: WIN32. (line 401) +* what is this?: Overview. (line 6) +* wildcard file name patterns: Input Section Wildcards. + (line 6) +* Xtensa options: Xtensa. (line 56) +* Xtensa processors: Xtensa. (line 6) + + + +Tag Table: +Node: Top759 +Node: Overview1542 +Node: Invocation2656 +Node: Options3064 +Node: Environment90607 +Node: Scripts92367 +Node: Basic Script Concepts94101 +Node: Script Format96808 +Node: Simple Example97671 +Node: Simple Commands100767 +Node: Entry Point101273 +Node: File Commands102032 +Node: Format Commands106033 +Node: REGION_ALIAS107989 +Node: Miscellaneous Commands112821 +Node: Assignments116197 +Node: Simple Assignments116688 +Node: PROVIDE118424 +Node: PROVIDE_HIDDEN119629 +Node: Source Code Reference119873 +Node: SECTIONS123453 +Node: Output Section Description125344 +Node: Output Section Name126431 +Node: Output Section Address127307 +Node: Input Section129027 +Node: Input Section Basics129828 +Node: Input Section Wildcards133046 +Node: Input Section Common137779 +Node: Input Section Keep139261 +Node: Input Section Example139751 +Node: Output Section Data140719 +Node: Output Section Keywords143496 +Node: Output Section Discarding147065 +Node: Output Section Attributes148246 +Node: Output Section Type149347 +Node: Output Section LMA150501 +Node: Forced Output Alignment153014 +Node: Forced Input Alignment153282 +Node: Output Section Constraint153671 +Node: Output Section Region154099 +Node: Output Section Phdr154532 +Node: Output Section Fill155196 +Node: Overlay Description156338 +Node: MEMORY160641 +Node: PHDRS164974 +Node: VERSION170013 +Node: Expressions178088 +Node: Constants179017 +Node: Symbolic Constants179892 +Node: Symbols180443 +Node: Orphan Sections181190 +Node: Location Counter182354 +Node: Operators186790 +Node: Evaluation187712 +Node: Expression Section189076 +Node: Builtin Functions190565 +Node: Implicit Linker Scripts198532 +Node: Machine Dependent199307 +Node: H8/300200323 +Node: i960201948 +Node: M68HC11/68HC12204049 +Node: ARM205503 +Node: HPPA ELF32213015 +Node: M68K214638 +Node: MMIX215547 +Node: MSP430216712 +Node: PowerPC ELF32217761 +Node: PowerPC64 ELF64220597 +Node: SPU ELF225013 +Node: TI COFF227645 +Node: WIN32228171 +Node: Xtensa247895 +Node: BFD251017 +Node: BFD outline252472 +Node: BFD information loss253758 +Node: Canonical format256275 +Node: Reporting Bugs260632 +Node: Bug Criteria261326 +Node: Bug Reporting262025 +Node: MRI269064 +Node: GNU Free Documentation License273707 +Node: LD Index293424 + +End Tag Table diff --git a/uclibc-crosstools-gcc-4.4.2-1/usr/share/info/standards.info b/uclibc-crosstools-gcc-4.4.2-1/usr/share/info/standards.info new file mode 100644 index 0000000..69b594f --- /dev/null +++ b/uclibc-crosstools-gcc-4.4.2-1/usr/share/info/standards.info @@ -0,0 +1,5576 @@ +This is standards.info, produced by makeinfo version 4.8 from +./standards.texi. + +INFO-DIR-SECTION GNU organization +START-INFO-DIR-ENTRY +* Standards: (standards). GNU coding standards. +END-INFO-DIR-ENTRY + + The GNU coding standards, last updated July 22, 2007. + + Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, +2001, 2002, 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc. + + Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.2 or +any later version published by the Free Software Foundation; with no +Invariant Sections, with no Front-Cover Texts, and with no Back-Cover +Texts. A copy of the license is included in the section entitled "GNU +Free Documentation License". + + +File: standards.info, Node: Top, Next: Preface, Prev: (dir), Up: (dir) + +Version +******* + +The GNU coding standards, last updated July 22, 2007. + + Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, +2001, 2002, 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc. + + Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.2 or +any later version published by the Free Software Foundation; with no +Invariant Sections, with no Front-Cover Texts, and with no Back-Cover +Texts. A copy of the license is included in the section entitled "GNU +Free Documentation License". + +* Menu: + +* Preface:: About the GNU Coding Standards. +* Legal Issues:: Keeping free software free. +* Design Advice:: General program design. +* Program Behavior:: Program behavior for all programs +* Writing C:: Making the best use of C. +* Documentation:: Documenting programs. +* Managing Releases:: The release process. +* References:: Mentioning non-free software or documentation. +* GNU Free Documentation License:: Copying and sharing this manual. +* Index:: + + +File: standards.info, Node: Preface, Next: Legal Issues, Prev: Top, Up: Top + +1 About the GNU Coding Standards +******************************** + +The GNU Coding Standards were written by Richard Stallman and other GNU +Project volunteers. Their purpose is to make the GNU system clean, +consistent, and easy to install. This document can also be read as a +guide to writing portable, robust and reliable programs. It focuses on +programs written in C, but many of the rules and principles are useful +even if you write in another programming language. The rules often +state reasons for writing in a certain way. + + This release of the GNU Coding Standards was last updated July 22, +2007. + + If you did not obtain this file directly from the GNU project and +recently, please check for a newer version. You can get the GNU Coding +Standards from the GNU web server in many different formats, including +the Texinfo source, PDF, HTML, DVI, plain text, and more, at: +`http://www.gnu.org/prep/standards/'. + + Corrections or suggestions for this document should be sent to +<bug-standards@gnu.org>. If you make a suggestion, please include a +suggested new wording for it; our time is limited. We prefer a context +diff to the `standards.texi' or `make-stds.texi' files, but if you +don't have those files, please mail your suggestion anyway. + + These standards cover the minimum of what is important when writing a +GNU package. Likely, the need for additional standards will come up. +Sometimes, you might suggest that such standards be added to this +document. If you think your standards would be generally useful, please +do suggest them. + + You should also set standards for your package on many questions not +addressed or not firmly specified here. The most important point is to +be self-consistent--try to stick to the conventions you pick, and try +to document them as much as possible. That way, your program will be +more maintainable by others. + + The GNU Hello program serves as an example of how to follow the GNU +coding standards for a trivial program. +`http://www.gnu.org/software/hello/hello.html'. + + +File: standards.info, Node: Legal Issues, Next: Design Advice, Prev: Preface, Up: Top + +2 Keeping Free Software Free +**************************** + +This chapter discusses how you can make sure that GNU software avoids +legal difficulties, and other related issues. + +* Menu: + +* Reading Non-Free Code:: Referring to proprietary programs. +* Contributions:: Accepting contributions. +* Trademarks:: How we deal with trademark issues. + + +File: standards.info, Node: Reading Non-Free Code, Next: Contributions, Up: Legal Issues + +2.1 Referring to Proprietary Programs +===================================== + +Don't in any circumstances refer to Unix source code for or during your +work on GNU! (Or to any other proprietary programs.) + + If you have a vague recollection of the internals of a Unix program, +this does not absolutely mean you can't write an imitation of it, but +do try to organize the imitation internally along different lines, +because this is likely to make the details of the Unix version +irrelevant and dissimilar to your results. + + For example, Unix utilities were generally optimized to minimize +memory use; if you go for speed instead, your program will be very +different. You could keep the entire input file in memory and scan it +there instead of using stdio. Use a smarter algorithm discovered more +recently than the Unix program. Eliminate use of temporary files. Do +it in one pass instead of two (we did this in the assembler). + + Or, on the contrary, emphasize simplicity instead of speed. For some +applications, the speed of today's computers makes simpler algorithms +adequate. + + Or go for generality. For example, Unix programs often have static +tables or fixed-size strings, which make for arbitrary limits; use +dynamic allocation instead. Make sure your program handles NULs and +other funny characters in the input files. Add a programming language +for extensibility and write part of the program in that language. + + Or turn some parts of the program into independently usable +libraries. Or use a simple garbage collector instead of tracking +precisely when to free memory, or use a new GNU facility such as +obstacks. + + +File: standards.info, Node: Contributions, Next: Trademarks, Prev: Reading Non-Free Code, Up: Legal Issues + +2.2 Accepting Contributions +=========================== + +If the program you are working on is copyrighted by the Free Software +Foundation, then when someone else sends you a piece of code to add to +the program, we need legal papers to use it--just as we asked you to +sign papers initially. _Each_ person who makes a nontrivial +contribution to a program must sign some sort of legal papers in order +for us to have clear title to the program; the main author alone is not +enough. + + So, before adding in any contributions from other people, please tell +us, so we can arrange to get the papers. Then wait until we tell you +that we have received the signed papers, before you actually use the +contribution. + + This applies both before you release the program and afterward. If +you receive diffs to fix a bug, and they make significant changes, we +need legal papers for that change. + + This also applies to comments and documentation files. For copyright +law, comments and code are just text. Copyright applies to all kinds of +text, so we need legal papers for all kinds. + + We know it is frustrating to ask for legal papers; it's frustrating +for us as well. But if you don't wait, you are going out on a limb--for +example, what if the contributor's employer won't sign a disclaimer? +You might have to take that code out again! + + You don't need papers for changes of a few lines here or there, since +they are not significant for copyright purposes. Also, you don't need +papers if all you get from the suggestion is some ideas, not actual code +which you use. For example, if someone sent you one implementation, but +you write a different implementation of the same idea, you don't need to +get papers. + + The very worst thing is if you forget to tell us about the other +contributor. We could be very embarrassed in court some day as a +result. + + We have more detailed advice for maintainers of programs; if you have +reached the stage of actually maintaining a program for GNU (whether +released or not), please ask us for a copy. It is also available +online for your perusal: `http://www.gnu.org/prep/maintain/'. + + +File: standards.info, Node: Trademarks, Prev: Contributions, Up: Legal Issues + +2.3 Trademarks +============== + +Please do not include any trademark acknowledgements in GNU software +packages or documentation. + + Trademark acknowledgements are the statements that such-and-such is a +trademark of so-and-so. The GNU Project has no objection to the basic +idea of trademarks, but these acknowledgements feel like kowtowing, and +there is no legal requirement for them, so we don't use them. + + What is legally required, as regards other people's trademarks, is to +avoid using them in ways which a reader might reasonably understand as +naming or labeling our own programs or activities. For example, since +"Objective C" is (or at least was) a trademark, we made sure to say +that we provide a "compiler for the Objective C language" rather than +an "Objective C compiler". The latter would have been meant as a +shorter way of saying the former, but it does not explicitly state the +relationship, so it could be misinterpreted as using "Objective C" as a +label for the compiler rather than for the language. + + Please don't use "win" as an abbreviation for Microsoft Windows in +GNU software or documentation. In hacker terminology, calling +something a "win" is a form of praise. If you wish to praise Microsoft +Windows when speaking on your own, by all means do so, but not in GNU +software. Usually we write the name "Windows" in full, but when +brevity is very important (as in file names and sometimes symbol +names), we abbreviate it to "w". For instance, the files and functions +in Emacs that deal with Windows start with `w32'. + + +File: standards.info, Node: Design Advice, Next: Program Behavior, Prev: Legal Issues, Up: Top + +3 General Program Design +************************ + +This chapter discusses some of the issues you should take into account +when designing your program. + +* Menu: + +* Source Language:: Which languages to use. +* Compatibility:: Compatibility with other implementations. +* Using Extensions:: Using non-standard features. +* Standard C:: Using standard C features. +* Conditional Compilation:: Compiling code only if a conditional is true. + + +File: standards.info, Node: Source Language, Next: Compatibility, Up: Design Advice + +3.1 Which Languages to Use +========================== + +When you want to use a language that gets compiled and runs at high +speed, the best language to use is C. Using another language is like +using a non-standard feature: it will cause trouble for users. Even if +GCC supports the other language, users may find it inconvenient to have +to install the compiler for that other language in order to build your +program. For example, if you write your program in C++, people will +have to install the GNU C++ compiler in order to compile your program. + + C has one other advantage over C++ and other compiled languages: more +people know C, so more people will find it easy to read and modify the +program if it is written in C. + + So in general it is much better to use C, rather than the comparable +alternatives. + + But there are two exceptions to that conclusion: + + * It is no problem to use another language to write a tool + specifically intended for use with that language. That is because + the only people who want to build the tool will be those who have + installed the other language anyway. + + * If an application is of interest only to a narrow part of the + community, then the question of which language it is written in + has less effect on other people, so you may as well please + yourself. + + Many programs are designed to be extensible: they include an +interpreter for a language that is higher level than C. Often much of +the program is written in that language, too. The Emacs editor +pioneered this technique. + + The standard extensibility interpreter for GNU software is GUILE +(`http://www.gnu.org/software/guile/'), which implements the language +Scheme (an especially clean and simple dialect of Lisp). We don't +reject programs written in other "scripting languages" such as Perl and +Python, but using GUILE is very important for the overall consistency +of the GNU system. + + +File: standards.info, Node: Compatibility, Next: Using Extensions, Prev: Source Language, Up: Design Advice + +3.2 Compatibility with Other Implementations +============================================ + +With occasional exceptions, utility programs and libraries for GNU +should be upward compatible with those in Berkeley Unix, and upward +compatible with Standard C if Standard C specifies their behavior, and +upward compatible with POSIX if POSIX specifies their behavior. + + When these standards conflict, it is useful to offer compatibility +modes for each of them. + + Standard C and POSIX prohibit many kinds of extensions. Feel free +to make the extensions anyway, and include a `--ansi', `--posix', or +`--compatible' option to turn them off. However, if the extension has +a significant chance of breaking any real programs or scripts, then it +is not really upward compatible. So you should try to redesign its +interface to make it upward compatible. + + Many GNU programs suppress extensions that conflict with POSIX if the +environment variable `POSIXLY_CORRECT' is defined (even if it is +defined with a null value). Please make your program recognize this +variable if appropriate. + + When a feature is used only by users (not by programs or command +files), and it is done poorly in Unix, feel free to replace it +completely with something totally different and better. (For example, +`vi' is replaced with Emacs.) But it is nice to offer a compatible +feature as well. (There is a free `vi' clone, so we offer it.) + + Additional useful features are welcome regardless of whether there +is any precedent for them. + + +File: standards.info, Node: Using Extensions, Next: Standard C, Prev: Compatibility, Up: Design Advice + +3.3 Using Non-standard Features +=============================== + +Many GNU facilities that already exist support a number of convenient +extensions over the comparable Unix facilities. Whether to use these +extensions in implementing your program is a difficult question. + + On the one hand, using the extensions can make a cleaner program. +On the other hand, people will not be able to build the program unless +the other GNU tools are available. This might cause the program to +work on fewer kinds of machines. + + With some extensions, it might be easy to provide both alternatives. +For example, you can define functions with a "keyword" `INLINE' and +define that as a macro to expand into either `inline' or nothing, +depending on the compiler. + + In general, perhaps it is best not to use the extensions if you can +straightforwardly do without them, but to use the extensions if they +are a big improvement. + + An exception to this rule are the large, established programs (such +as Emacs) which run on a great variety of systems. Using GNU +extensions in such programs would make many users unhappy, so we don't +do that. + + Another exception is for programs that are used as part of +compilation: anything that must be compiled with other compilers in +order to bootstrap the GNU compilation facilities. If these require +the GNU compiler, then no one can compile them without having them +installed already. That would be extremely troublesome in certain +cases. + + +File: standards.info, Node: Standard C, Next: Conditional Compilation, Prev: Using Extensions, Up: Design Advice + +3.4 Standard C and Pre-Standard C +================================= + +1989 Standard C is widespread enough now that it is ok to use its +features in new programs. There is one exception: do not ever use the +"trigraph" feature of Standard C. + + 1999 Standard C is not widespread yet, so please do not require its +features in programs. It is ok to use its features if they are present. + + However, it is easy to support pre-standard compilers in most +programs, so if you know how to do that, feel free. If a program you +are maintaining has such support, you should try to keep it working. + + To support pre-standard C, instead of writing function definitions in +standard prototype form, + + int + foo (int x, int y) + ... + +write the definition in pre-standard style like this, + + int + foo (x, y) + int x, y; + ... + +and use a separate declaration to specify the argument prototype: + + int foo (int, int); + + You need such a declaration anyway, in a header file, to get the +benefit of prototypes in all the files where the function is called. +And once you have the declaration, you normally lose nothing by writing +the function definition in the pre-standard style. + + This technique does not work for integer types narrower than `int'. +If you think of an argument as being of a type narrower than `int', +declare it as `int' instead. + + There are a few special cases where this technique is hard to use. +For example, if a function argument needs to hold the system type +`dev_t', you run into trouble, because `dev_t' is shorter than `int' on +some machines; but you cannot use `int' instead, because `dev_t' is +wider than `int' on some machines. There is no type you can safely use +on all machines in a non-standard definition. The only way to support +non-standard C and pass such an argument is to check the width of +`dev_t' using Autoconf and choose the argument type accordingly. This +may not be worth the trouble. + + In order to support pre-standard compilers that do not recognize +prototypes, you may want to use a preprocessor macro like this: + + /* Declare the prototype for a general external function. */ + #if defined (__STDC__) || defined (WINDOWSNT) + #define P_(proto) proto + #else + #define P_(proto) () + #endif + + +File: standards.info, Node: Conditional Compilation, Prev: Standard C, Up: Design Advice + +3.5 Conditional Compilation +=========================== + +When supporting configuration options already known when building your +program we prefer using `if (... )' over conditional compilation, as in +the former case the compiler is able to perform more extensive checking +of all possible code paths. + + For example, please write + + if (HAS_FOO) + ... + else + ... + +instead of: + + #ifdef HAS_FOO + ... + #else + ... + #endif + + A modern compiler such as GCC will generate exactly the same code in +both cases, and we have been using similar techniques with good success +in several projects. Of course, the former method assumes that +`HAS_FOO' is defined as either 0 or 1. + + While this is not a silver bullet solving all portability problems, +and is not always appropriate, following this policy would have saved +GCC developers many hours, or even days, per year. + + In the case of function-like macros like `REVERSIBLE_CC_MODE' in GCC +which cannot be simply used in `if( ...)' statements, there is an easy +workaround. Simply introduce another macro `HAS_REVERSIBLE_CC_MODE' as +in the following example: + + #ifdef REVERSIBLE_CC_MODE + #define HAS_REVERSIBLE_CC_MODE 1 + #else + #define HAS_REVERSIBLE_CC_MODE 0 + #endif + + +File: standards.info, Node: Program Behavior, Next: Writing C, Prev: Design Advice, Up: Top + +4 Program Behavior for All Programs +*********************************** + +This chapter describes conventions for writing robust software. It +also describes general standards for error messages, the command line +interface, and how libraries should behave. + +* Menu: + +* Non-GNU Standards:: We consider standards such as POSIX; + we don't "obey" them. +* Semantics:: Writing robust programs. +* Libraries:: Library behavior. +* Errors:: Formatting error messages. +* User Interfaces:: Standards about interfaces generally. +* Graphical Interfaces:: Standards for graphical interfaces. +* Command-Line Interfaces:: Standards for command line interfaces. +* Option Table:: Table of long options. +* Memory Usage:: When and how to care about memory needs. +* File Usage:: Which files to use, and where. + + +File: standards.info, Node: Non-GNU Standards, Next: Semantics, Up: Program Behavior + +4.1 Non-GNU Standards +===================== + +The GNU Project regards standards published by other organizations as +suggestions, not orders. We consider those standards, but we do not +"obey" them. In developing a GNU program, you should implement an +outside standard's specifications when that makes the GNU system better +overall in an objective sense. When it doesn't, you shouldn't. + + In most cases, following published standards is convenient for +users--it means that their programs or scripts will work more portably. +For instance, GCC implements nearly all the features of Standard C as +specified by that standard. C program developers would be unhappy if +it did not. And GNU utilities mostly follow specifications of POSIX.2; +shell script writers and users would be unhappy if our programs were +incompatible. + + But we do not follow either of these specifications rigidly, and +there are specific points on which we decided not to follow them, so as +to make the GNU system better for users. + + For instance, Standard C says that nearly all extensions to C are +prohibited. How silly! GCC implements many extensions, some of which +were later adopted as part of the standard. If you want these +constructs to give an error message as "required" by the standard, you +must specify `--pedantic', which was implemented only so that we can +say "GCC is a 100% implementation of the standard," not because there +is any reason to actually use it. + + POSIX.2 specifies that `df' and `du' must output sizes by default in +units of 512 bytes. What users want is units of 1k, so that is what we +do by default. If you want the ridiculous behavior "required" by +POSIX, you must set the environment variable `POSIXLY_CORRECT' (which +was originally going to be named `POSIX_ME_HARDER'). + + GNU utilities also depart from the letter of the POSIX.2 +specification when they support long-named command-line options, and +intermixing options with ordinary arguments. This minor +incompatibility with POSIX is never a problem in practice, and it is +very useful. + + In particular, don't reject a new feature, or remove an old one, +merely because a standard says it is "forbidden" or "deprecated." + + +File: standards.info, Node: Semantics, Next: Libraries, Prev: Non-GNU Standards, Up: Program Behavior + +4.2 Writing Robust Programs +=========================== + +Avoid arbitrary limits on the length or number of _any_ data structure, +including file names, lines, files, and symbols, by allocating all data +structures dynamically. In most Unix utilities, "long lines are +silently truncated". This is not acceptable in a GNU utility. + + Utilities reading files should not drop NUL characters, or any other +nonprinting characters _including those with codes above 0177_. The +only sensible exceptions would be utilities specifically intended for +interface to certain types of terminals or printers that can't handle +those characters. Whenever possible, try to make programs work +properly with sequences of bytes that represent multibyte characters, +using encodings such as UTF-8 and others. + + Check every system call for an error return, unless you know you +wish to ignore errors. Include the system error text (from `perror' or +equivalent) in _every_ error message resulting from a failing system +call, as well as the name of the file if any and the name of the +utility. Just "cannot open foo.c" or "stat failed" is not sufficient. + + Check every call to `malloc' or `realloc' to see if it returned +zero. Check `realloc' even if you are making the block smaller; in a +system that rounds block sizes to a power of 2, `realloc' may get a +different block if you ask for less space. + + In Unix, `realloc' can destroy the storage block if it returns zero. +GNU `realloc' does not have this bug: if it fails, the original block +is unchanged. Feel free to assume the bug is fixed. If you wish to +run your program on Unix, and wish to avoid lossage in this case, you +can use the GNU `malloc'. + + You must expect `free' to alter the contents of the block that was +freed. Anything you want to fetch from the block, you must fetch before +calling `free'. + + If `malloc' fails in a noninteractive program, make that a fatal +error. In an interactive program (one that reads commands from the +user), it is better to abort the command and return to the command +reader loop. This allows the user to kill other processes to free up +virtual memory, and then try the command again. + + Use `getopt_long' to decode arguments, unless the argument syntax +makes this unreasonable. + + When static storage is to be written in during program execution, use +explicit C code to initialize it. Reserve C initialized declarations +for data that will not be changed. + + Try to avoid low-level interfaces to obscure Unix data structures +(such as file directories, utmp, or the layout of kernel memory), since +these are less likely to work compatibly. If you need to find all the +files in a directory, use `readdir' or some other high-level interface. +These are supported compatibly by GNU. + + The preferred signal handling facilities are the BSD variant of +`signal', and the POSIX `sigaction' function; the alternative USG +`signal' interface is an inferior design. + + Nowadays, using the POSIX signal functions may be the easiest way to +make a program portable. If you use `signal', then on GNU/Linux +systems running GNU libc version 1, you should include `bsd/signal.h' +instead of `signal.h', so as to get BSD behavior. It is up to you +whether to support systems where `signal' has only the USG behavior, or +give up on them. + + In error checks that detect "impossible" conditions, just abort. +There is usually no point in printing any message. These checks +indicate the existence of bugs. Whoever wants to fix the bugs will have +to read the source code and run a debugger. So explain the problem with +comments in the source. The relevant data will be in variables, which +are easy to examine with the debugger, so there is no point moving them +elsewhere. + + Do not use a count of errors as the exit status for a program. +_That does not work_, because exit status values are limited to 8 bits +(0 through 255). A single run of the program might have 256 errors; if +you try to return 256 as the exit status, the parent process will see 0 +as the status, and it will appear that the program succeeded. + + If you make temporary files, check the `TMPDIR' environment +variable; if that variable is defined, use the specified directory +instead of `/tmp'. + + In addition, be aware that there is a possible security problem when +creating temporary files in world-writable directories. In C, you can +avoid this problem by creating temporary files in this manner: + + fd = open(filename, O_WRONLY | O_CREAT | O_EXCL, 0600); + +or by using the `mkstemps' function from libiberty. + + In bash, use `set -C' to avoid this problem. + + +File: standards.info, Node: Libraries, Next: Errors, Prev: Semantics, Up: Program Behavior + +4.3 Library Behavior +==================== + +Try to make library functions reentrant. If they need to do dynamic +storage allocation, at least try to avoid any nonreentrancy aside from +that of `malloc' itself. + + Here are certain name conventions for libraries, to avoid name +conflicts. + + Choose a name prefix for the library, more than two characters long. +All external function and variable names should start with this prefix. +In addition, there should only be one of these in any given library +member. This usually means putting each one in a separate source file. + + An exception can be made when two external symbols are always used +together, so that no reasonable program could use one without the +other; then they can both go in the same file. + + External symbols that are not documented entry points for the user +should have names beginning with `_'. The `_' should be followed by +the chosen name prefix for the library, to prevent collisions with +other libraries. These can go in the same files with user entry points +if you like. + + Static functions and variables can be used as you like and need not +fit any naming convention. + + +File: standards.info, Node: Errors, Next: User Interfaces, Prev: Libraries, Up: Program Behavior + +4.4 Formatting Error Messages +============================= + +Error messages from compilers should look like this: + + SOURCE-FILE-NAME:LINENO: MESSAGE + +If you want to mention the column number, use one of these formats: + + SOURCE-FILE-NAME:LINENO:COLUMN: MESSAGE + SOURCE-FILE-NAME:LINENO.COLUMN: MESSAGE + +Line numbers should start from 1 at the beginning of the file, and +column numbers should start from 1 at the beginning of the line. (Both +of these conventions are chosen for compatibility.) Calculate column +numbers assuming that space and all ASCII printing characters have +equal width, and assuming tab stops every 8 columns. + + The error message can also give both the starting and ending +positions of the erroneous text. There are several formats so that you +can avoid redundant information such as a duplicate line number. Here +are the possible formats: + + SOURCE-FILE-NAME:LINENO-1.COLUMN-1-LINENO-2.COLUMN-2: MESSAGE + SOURCE-FILE-NAME:LINENO-1.COLUMN-1-COLUMN-2: MESSAGE + SOURCE-FILE-NAME:LINENO-1-LINENO-2: MESSAGE + +When an error is spread over several files, you can use this format: + + FILE-1:LINENO-1.COLUMN-1-FILE-2:LINENO-2.COLUMN-2: MESSAGE + + Error messages from other noninteractive programs should look like +this: + + PROGRAM:SOURCE-FILE-NAME:LINENO: MESSAGE + +when there is an appropriate source file, or like this: + + PROGRAM: MESSAGE + +when there is no relevant source file. + + If you want to mention the column number, use this format: + + PROGRAM:SOURCE-FILE-NAME:LINENO:COLUMN: MESSAGE + + In an interactive program (one that is reading commands from a +terminal), it is better not to include the program name in an error +message. The place to indicate which program is running is in the +prompt or with the screen layout. (When the same program runs with +input from a source other than a terminal, it is not interactive and +would do best to print error messages using the noninteractive style.) + + The string MESSAGE should not begin with a capital letter when it +follows a program name and/or file name, because that isn't the +beginning of a sentence. (The sentence conceptually starts at the +beginning of the line.) Also, it should not end with a period. + + Error messages from interactive programs, and other messages such as +usage messages, should start with a capital letter. But they should not +end with a period. + + +File: standards.info, Node: User Interfaces, Next: Graphical Interfaces, Prev: Errors, Up: Program Behavior + +4.5 Standards for Interfaces Generally +====================================== + +Please don't make the behavior of a utility depend on the name used to +invoke it. It is useful sometimes to make a link to a utility with a +different name, and that should not change what it does. + + Instead, use a run time option or a compilation switch or both to +select among the alternate behaviors. + + Likewise, please don't make the behavior of the program depend on the +type of output device it is used with. Device independence is an +important principle of the system's design; do not compromise it merely +to save someone from typing an option now and then. (Variation in error +message syntax when using a terminal is ok, because that is a side issue +that people do not depend on.) + + If you think one behavior is most useful when the output is to a +terminal, and another is most useful when the output is a file or a +pipe, then it is usually best to make the default behavior the one that +is useful with output to a terminal, and have an option for the other +behavior. + + Compatibility requires certain programs to depend on the type of +output device. It would be disastrous if `ls' or `sh' did not do so in +the way all users expect. In some of these cases, we supplement the +program with a preferred alternate version that does not depend on the +output device type. For example, we provide a `dir' program much like +`ls' except that its default output format is always multi-column +format. + + +File: standards.info, Node: Graphical Interfaces, Next: Command-Line Interfaces, Prev: User Interfaces, Up: Program Behavior + +4.6 Standards for Graphical Interfaces +====================================== + +When you write a program that provides a graphical user interface, +please make it work with X Windows and the GTK+ toolkit unless the +functionality specifically requires some alternative (for example, +"displaying jpeg images while in console mode"). + + In addition, please provide a command-line interface to control the +functionality. (In many cases, the graphical user interface can be a +separate program which invokes the command-line program.) This is so +that the same jobs can be done from scripts. + + Please also consider providing a CORBA interface (for use from +GNOME), a library interface (for use from C), and perhaps a +keyboard-driven console interface (for use by users from console mode). +Once you are doing the work to provide the functionality and the +graphical interface, these won't be much extra work. + + +File: standards.info, Node: Command-Line Interfaces, Next: Option Table, Prev: Graphical Interfaces, Up: Program Behavior + +4.7 Standards for Command Line Interfaces +========================================= + +It is a good idea to follow the POSIX guidelines for the command-line +options of a program. The easiest way to do this is to use `getopt' to +parse them. Note that the GNU version of `getopt' will normally permit +options anywhere among the arguments unless the special argument `--' +is used. This is not what POSIX specifies; it is a GNU extension. + + Please define long-named options that are equivalent to the +single-letter Unix-style options. We hope to make GNU more user +friendly this way. This is easy to do with the GNU function +`getopt_long'. + + One of the advantages of long-named options is that they can be +consistent from program to program. For example, users should be able +to expect the "verbose" option of any GNU program which has one, to be +spelled precisely `--verbose'. To achieve this uniformity, look at the +table of common long-option names when you choose the option names for +your program (*note Option Table::). + + It is usually a good idea for file names given as ordinary arguments +to be input files only; any output files would be specified using +options (preferably `-o' or `--output'). Even if you allow an output +file name as an ordinary argument for compatibility, try to provide an +option as another way to specify it. This will lead to more consistency +among GNU utilities, and fewer idiosyncrasies for users to remember. + + All programs should support two standard options: `--version' and +`--help'. CGI programs should accept these as command-line options, +and also if given as the `PATH_INFO'; for instance, visiting +`http://example.org/p.cgi/--help' in a browser should output the same +information as invoking `p.cgi --help' from the command line. + +* Menu: + +* --version:: The standard output for --version. +* --help:: The standard output for --help. + + +File: standards.info, Node: --version, Next: --help, Up: Command-Line Interfaces + +4.7.1 `--version' +----------------- + +The standard `--version' option should direct the program to print +information about its name, version, origin and legal status, all on +standard output, and then exit successfully. Other options and +arguments should be ignored once this is seen, and the program should +not perform its normal function. + + The first line is meant to be easy for a program to parse; the +version number proper starts after the last space. In addition, it +contains the canonical name for this program, in this format: + + GNU Emacs 19.30 + +The program's name should be a constant string; _don't_ compute it from +`argv[0]'. The idea is to state the standard or canonical name for the +program, not its file name. There are other ways to find out the +precise file name where a command is found in `PATH'. + + If the program is a subsidiary part of a larger package, mention the +package name in parentheses, like this: + + emacsserver (GNU Emacs) 19.30 + +If the package has a version number which is different from this +program's version number, you can mention the package version number +just before the close-parenthesis. + + If you _need_ to mention the version numbers of libraries which are +distributed separately from the package which contains this program, +you can do so by printing an additional line of version info for each +library you want to mention. Use the same format for these lines as for +the first line. + + Please do not mention all of the libraries that the program uses +"just for completeness"--that would produce a lot of unhelpful clutter. +Please mention library version numbers only if you find in practice that +they are very important to you in debugging. + + The following line, after the version number line or lines, should +be a copyright notice. If more than one copyright notice is called +for, put each on a separate line. + + Next should follow a line stating the license, preferably using one +of abbrevations below, and a brief statement that the program is free +software, and that users are free to copy and change it. Also mention +that there is no warranty, to the extent permitted by law. See +recommended wording below. + + It is ok to finish the output with a list of the major authors of the +program, as a way of giving credit. + + Here's an example of output that follows these rules: + + GNU hello 2.3 + Copyright (C) 2007 Free Software Foundation, Inc. + License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> + This is free software: you are free to change and redistribute it. + There is NO WARRANTY, to the extent permitted by law. + + You should adapt this to your program, of course, filling in the +proper year, copyright holder, name of program, and the references to +distribution terms, and changing the rest of the wording as necessary. + + This copyright notice only needs to mention the most recent year in +which changes were made--there's no need to list the years for previous +versions' changes. You don't have to mention the name of the program in +these notices, if that is inconvenient, since it appeared in the first +line. (The rules are different for copyright notices in source files; +*note Copyright Notices: (maintain)Copyright Notices.) + + Translations of the above lines must preserve the validity of the +copyright notices (*note Internationalization::). If the translation's +character set supports it, the `(C)' should be replaced with the +copyright symbol, as follows: + + (the official copyright symbol, which is the letter C in a circle); + + Write the word "Copyright" exactly like that, in English. Do not +translate it into another language. International treaties recognize +the English word "Copyright"; translations into other languages do not +have legal significance. + + Finally, here is the table of our suggested license abbreviations. +Any abbreviation can be followed by `vVERSION[+]', meaning that +particular version, or later versions with the `+', as shown above. + + In the case of exceptions for extra permissions with the GPL, we use +`/' for a separator; the version number can follow the license +abbreviation as usual, as in the examples below. + +GPL + GNU General Public License, `http://www.gnu.org/licenses/gpl.html'. + +LGPL + GNU Lesser General Public License, + `http://www.gnu.org/licenses/lgpl.html'. + +GPL/Guile + GNU GPL with the exception for Guile; for example, GPLv3+/Guile + means the GNU GPL version 3 or later, with the extra exception for + Guile. + + GNU GPL with the exception for Ada. + +Apache + The Apache Software Foundation license, + `http://www.apache.org/licenses'. + +Artistic + The Artistic license used for Perl, + `http://www.perlfoundation.org/legal'. + +Expat + The Expat license, `http://www.jclark.com/xml/copying.txt'. + +MPL + The Mozilla Public License, `http://www.mozilla.org/MPL/'. + +OBSD + The original (4-clause) BSD license, incompatible with the GNU GPL + `http://www.xfree86.org/3.3.6/COPYRIGHT2.html#6'. + +PHP + The license used for PHP, `http://www.php.net/license/'. + +public domain + The non-license that is being in the public domain, + `http://www.gnu.org/licenses/license-list.html#PublicDomain'. + +Python + The license for Python, `http://www.python.org/2.0.1/license.html'. + +RBSD + The revised (3-clause) BSD, compatible with the GNU GPL, + `http://www.xfree86.org/3.3.6/COPYRIGHT2.html#5'. + +X11 + The simple non-copyleft license used for most versions of the X + Window system, `http://www.xfree86.org/3.3.6/COPYRIGHT2.html#3'. + +Zlib + The license for Zlib, `http://www.gzip.org/zlib/zlib_license.html'. + + + More information about these licenses and many more are on the GNU +licensing web pages, `http://www.gnu.org/licenses/license-list.html'. + + +File: standards.info, Node: --help, Prev: --version, Up: Command-Line Interfaces + +4.7.2 `--help' +-------------- + +The standard `--help' option should output brief documentation for how +to invoke the program, on standard output, then exit successfully. +Other options and arguments should be ignored once this is seen, and +the program should not perform its normal function. + + Near the end of the `--help' option's output there should be a line +that says where to mail bug reports. It should have this format: + + Report bugs to MAILING-ADDRESS. + + +File: standards.info, Node: Option Table, Next: Memory Usage, Prev: Command-Line Interfaces, Up: Program Behavior + +4.8 Table of Long Options +========================= + +Here is a table of long options used by GNU programs. It is surely +incomplete, but we aim to list all the options that a new program might +want to be compatible with. If you use names not already in the table, +please send <bug-standards@gnu.org> a list of them, with their +meanings, so we can update the table. + +`after-date' + `-N' in `tar'. + +`all' + `-a' in `du', `ls', `nm', `stty', `uname', and `unexpand'. + +`all-text' + `-a' in `diff'. + +`almost-all' + `-A' in `ls'. + +`append' + `-a' in `etags', `tee', `time'; `-r' in `tar'. + +`archive' + `-a' in `cp'. + +`archive-name' + `-n' in `shar'. + +`arglength' + `-l' in `m4'. + +`ascii' + `-a' in `diff'. + +`assign' + `-v' in `gawk'. + +`assume-new' + `-W' in Make. + +`assume-old' + `-o' in Make. + +`auto-check' + `-a' in `recode'. + +`auto-pager' + `-a' in `wdiff'. + +`auto-reference' + `-A' in `ptx'. + +`avoid-wraps' + `-n' in `wdiff'. + +`background' + For server programs, run in the background. + +`backward-search' + `-B' in `ctags'. + +`basename' + `-f' in `shar'. + +`batch' + Used in GDB. + +`baud' + Used in GDB. + +`before' + `-b' in `tac'. + +`binary' + `-b' in `cpio' and `diff'. + +`bits-per-code' + `-b' in `shar'. + +`block-size' + Used in `cpio' and `tar'. + +`blocks' + `-b' in `head' and `tail'. + +`break-file' + `-b' in `ptx'. + +`brief' + Used in various programs to make output shorter. + +`bytes' + `-c' in `head', `split', and `tail'. + +`c++' + `-C' in `etags'. + +`catenate' + `-A' in `tar'. + +`cd' + Used in various programs to specify the directory to use. + +`changes' + `-c' in `chgrp' and `chown'. + +`classify' + `-F' in `ls'. + +`colons' + `-c' in `recode'. + +`command' + `-c' in `su'; `-x' in GDB. + +`compare' + `-d' in `tar'. + +`compat' + Used in `gawk'. + +`compress' + `-Z' in `tar' and `shar'. + +`concatenate' + `-A' in `tar'. + +`confirmation' + `-w' in `tar'. + +`context' + Used in `diff'. + +`copyleft' + `-W copyleft' in `gawk'. + +`copyright' + `-C' in `ptx', `recode', and `wdiff'; `-W copyright' in `gawk'. + +`core' + Used in GDB. + +`count' + `-q' in `who'. + +`count-links' + `-l' in `du'. + +`create' + Used in `tar' and `cpio'. + +`cut-mark' + `-c' in `shar'. + +`cxref' + `-x' in `ctags'. + +`date' + `-d' in `touch'. + +`debug' + `-d' in Make and `m4'; `-t' in Bison. + +`define' + `-D' in `m4'. + +`defines' + `-d' in Bison and `ctags'. + +`delete' + `-D' in `tar'. + +`dereference' + `-L' in `chgrp', `chown', `cpio', `du', `ls', and `tar'. + +`dereference-args' + `-D' in `du'. + +`device' + Specify an I/O device (special file name). + +`diacritics' + `-d' in `recode'. + +`dictionary-order' + `-d' in `look'. + +`diff' + `-d' in `tar'. + +`digits' + `-n' in `csplit'. + +`directory' + Specify the directory to use, in various programs. In `ls', it + means to show directories themselves rather than their contents. + In `rm' and `ln', it means to not treat links to directories + specially. + +`discard-all' + `-x' in `strip'. + +`discard-locals' + `-X' in `strip'. + +`dry-run' + `-n' in Make. + +`ed' + `-e' in `diff'. + +`elide-empty-files' + `-z' in `csplit'. + +`end-delete' + `-x' in `wdiff'. + +`end-insert' + `-z' in `wdiff'. + +`entire-new-file' + `-N' in `diff'. + +`environment-overrides' + `-e' in Make. + +`eof' + `-e' in `xargs'. + +`epoch' + Used in GDB. + +`error-limit' + Used in `makeinfo'. + +`error-output' + `-o' in `m4'. + +`escape' + `-b' in `ls'. + +`exclude-from' + `-X' in `tar'. + +`exec' + Used in GDB. + +`exit' + `-x' in `xargs'. + +`exit-0' + `-e' in `unshar'. + +`expand-tabs' + `-t' in `diff'. + +`expression' + `-e' in `sed'. + +`extern-only' + `-g' in `nm'. + +`extract' + `-i' in `cpio'; `-x' in `tar'. + +`faces' + `-f' in `finger'. + +`fast' + `-f' in `su'. + +`fatal-warnings' + `-E' in `m4'. + +`file' + `-f' in `info', `gawk', Make, `mt', and `tar'; `-n' in `sed'; `-r' + in `touch'. + +`field-separator' + `-F' in `gawk'. + +`file-prefix' + `-b' in Bison. + +`file-type' + `-F' in `ls'. + +`files-from' + `-T' in `tar'. + +`fill-column' + Used in `makeinfo'. + +`flag-truncation' + `-F' in `ptx'. + +`fixed-output-files' + `-y' in Bison. + +`follow' + `-f' in `tail'. + +`footnote-style' + Used in `makeinfo'. + +`force' + `-f' in `cp', `ln', `mv', and `rm'. + +`force-prefix' + `-F' in `shar'. + +`foreground' + For server programs, run in the foreground; in other words, don't + do anything special to run the server in the background. + +`format' + Used in `ls', `time', and `ptx'. + +`freeze-state' + `-F' in `m4'. + +`fullname' + Used in GDB. + +`gap-size' + `-g' in `ptx'. + +`get' + `-x' in `tar'. + +`graphic' + `-i' in `ul'. + +`graphics' + `-g' in `recode'. + +`group' + `-g' in `install'. + +`gzip' + `-z' in `tar' and `shar'. + +`hashsize' + `-H' in `m4'. + +`header' + `-h' in `objdump' and `recode' + +`heading' + `-H' in `who'. + +`help' + Used to ask for brief usage information. + +`here-delimiter' + `-d' in `shar'. + +`hide-control-chars' + `-q' in `ls'. + +`html' + In `makeinfo', output HTML. + +`idle' + `-u' in `who'. + +`ifdef' + `-D' in `diff'. + +`ignore' + `-I' in `ls'; `-x' in `recode'. + +`ignore-all-space' + `-w' in `diff'. + +`ignore-backups' + `-B' in `ls'. + +`ignore-blank-lines' + `-B' in `diff'. + +`ignore-case' + `-f' in `look' and `ptx'; `-i' in `diff' and `wdiff'. + +`ignore-errors' + `-i' in Make. + +`ignore-file' + `-i' in `ptx'. + +`ignore-indentation' + `-I' in `etags'. + +`ignore-init-file' + `-f' in Oleo. + +`ignore-interrupts' + `-i' in `tee'. + +`ignore-matching-lines' + `-I' in `diff'. + +`ignore-space-change' + `-b' in `diff'. + +`ignore-zeros' + `-i' in `tar'. + +`include' + `-i' in `etags'; `-I' in `m4'. + +`include-dir' + `-I' in Make. + +`incremental' + `-G' in `tar'. + +`info' + `-i', `-l', and `-m' in Finger. + +`init-file' + In some programs, specify the name of the file to read as the + user's init file. + +`initial' + `-i' in `expand'. + +`initial-tab' + `-T' in `diff'. + +`inode' + `-i' in `ls'. + +`interactive' + `-i' in `cp', `ln', `mv', `rm'; `-e' in `m4'; `-p' in `xargs'; + `-w' in `tar'. + +`intermix-type' + `-p' in `shar'. + +`iso-8601' + Used in `date' + +`jobs' + `-j' in Make. + +`just-print' + `-n' in Make. + +`keep-going' + `-k' in Make. + +`keep-files' + `-k' in `csplit'. + +`kilobytes' + `-k' in `du' and `ls'. + +`language' + `-l' in `etags'. + +`less-mode' + `-l' in `wdiff'. + +`level-for-gzip' + `-g' in `shar'. + +`line-bytes' + `-C' in `split'. + +`lines' + Used in `split', `head', and `tail'. + +`link' + `-l' in `cpio'. + +`lint' +`lint-old' + Used in `gawk'. + +`list' + `-t' in `cpio'; `-l' in `recode'. + +`list' + `-t' in `tar'. + +`literal' + `-N' in `ls'. + +`load-average' + `-l' in Make. + +`login' + Used in `su'. + +`machine' + Used in `uname'. + +`macro-name' + `-M' in `ptx'. + +`mail' + `-m' in `hello' and `uname'. + +`make-directories' + `-d' in `cpio'. + +`makefile' + `-f' in Make. + +`mapped' + Used in GDB. + +`max-args' + `-n' in `xargs'. + +`max-chars' + `-n' in `xargs'. + +`max-lines' + `-l' in `xargs'. + +`max-load' + `-l' in Make. + +`max-procs' + `-P' in `xargs'. + +`mesg' + `-T' in `who'. + +`message' + `-T' in `who'. + +`minimal' + `-d' in `diff'. + +`mixed-uuencode' + `-M' in `shar'. + +`mode' + `-m' in `install', `mkdir', and `mkfifo'. + +`modification-time' + `-m' in `tar'. + +`multi-volume' + `-M' in `tar'. + +`name-prefix' + `-a' in Bison. + +`nesting-limit' + `-L' in `m4'. + +`net-headers' + `-a' in `shar'. + +`new-file' + `-W' in Make. + +`no-builtin-rules' + `-r' in Make. + +`no-character-count' + `-w' in `shar'. + +`no-check-existing' + `-x' in `shar'. + +`no-common' + `-3' in `wdiff'. + +`no-create' + `-c' in `touch'. + +`no-defines' + `-D' in `etags'. + +`no-deleted' + `-1' in `wdiff'. + +`no-dereference' + `-d' in `cp'. + +`no-inserted' + `-2' in `wdiff'. + +`no-keep-going' + `-S' in Make. + +`no-lines' + `-l' in Bison. + +`no-piping' + `-P' in `shar'. + +`no-prof' + `-e' in `gprof'. + +`no-regex' + `-R' in `etags'. + +`no-sort' + `-p' in `nm'. + +`no-splash' + Don't print a startup splash screen. + +`no-split' + Used in `makeinfo'. + +`no-static' + `-a' in `gprof'. + +`no-time' + `-E' in `gprof'. + +`no-timestamp' + `-m' in `shar'. + +`no-validate' + Used in `makeinfo'. + +`no-wait' + Used in `emacsclient'. + +`no-warn' + Used in various programs to inhibit warnings. + +`node' + `-n' in `info'. + +`nodename' + `-n' in `uname'. + +`nonmatching' + `-f' in `cpio'. + +`nstuff' + `-n' in `objdump'. + +`null' + `-0' in `xargs'. + +`number' + `-n' in `cat'. + +`number-nonblank' + `-b' in `cat'. + +`numeric-sort' + `-n' in `nm'. + +`numeric-uid-gid' + `-n' in `cpio' and `ls'. + +`nx' + Used in GDB. + +`old-archive' + `-o' in `tar'. + +`old-file' + `-o' in Make. + +`one-file-system' + `-l' in `tar', `cp', and `du'. + +`only-file' + `-o' in `ptx'. + +`only-prof' + `-f' in `gprof'. + +`only-time' + `-F' in `gprof'. + +`options' + `-o' in `getopt', `fdlist', `fdmount', `fdmountd', and `fdumount'. + +`output' + In various programs, specify the output file name. + +`output-prefix' + `-o' in `shar'. + +`override' + `-o' in `rm'. + +`overwrite' + `-c' in `unshar'. + +`owner' + `-o' in `install'. + +`paginate' + `-l' in `diff'. + +`paragraph-indent' + Used in `makeinfo'. + +`parents' + `-p' in `mkdir' and `rmdir'. + +`pass-all' + `-p' in `ul'. + +`pass-through' + `-p' in `cpio'. + +`port' + `-P' in `finger'. + +`portability' + `-c' in `cpio' and `tar'. + +`posix' + Used in `gawk'. + +`prefix-builtins' + `-P' in `m4'. + +`prefix' + `-f' in `csplit'. + +`preserve' + Used in `tar' and `cp'. + +`preserve-environment' + `-p' in `su'. + +`preserve-modification-time' + `-m' in `cpio'. + +`preserve-order' + `-s' in `tar'. + +`preserve-permissions' + `-p' in `tar'. + +`print' + `-l' in `diff'. + +`print-chars' + `-L' in `cmp'. + +`print-data-base' + `-p' in Make. + +`print-directory' + `-w' in Make. + +`print-file-name' + `-o' in `nm'. + +`print-symdefs' + `-s' in `nm'. + +`printer' + `-p' in `wdiff'. + +`prompt' + `-p' in `ed'. + +`proxy' + Specify an HTTP proxy. + +`query-user' + `-X' in `shar'. + +`question' + `-q' in Make. + +`quiet' + Used in many programs to inhibit the usual output. Every program + accepting `--quiet' should accept `--silent' as a synonym. + +`quiet-unshar' + `-Q' in `shar' + +`quote-name' + `-Q' in `ls'. + +`rcs' + `-n' in `diff'. + +`re-interval' + Used in `gawk'. + +`read-full-blocks' + `-B' in `tar'. + +`readnow' + Used in GDB. + +`recon' + `-n' in Make. + +`record-number' + `-R' in `tar'. + +`recursive' + Used in `chgrp', `chown', `cp', `ls', `diff', and `rm'. + +`reference-limit' + Used in `makeinfo'. + +`references' + `-r' in `ptx'. + +`regex' + `-r' in `tac' and `etags'. + +`release' + `-r' in `uname'. + +`reload-state' + `-R' in `m4'. + +`relocation' + `-r' in `objdump'. + +`rename' + `-r' in `cpio'. + +`replace' + `-i' in `xargs'. + +`report-identical-files' + `-s' in `diff'. + +`reset-access-time' + `-a' in `cpio'. + +`reverse' + `-r' in `ls' and `nm'. + +`reversed-ed' + `-f' in `diff'. + +`right-side-defs' + `-R' in `ptx'. + +`same-order' + `-s' in `tar'. + +`same-permissions' + `-p' in `tar'. + +`save' + `-g' in `stty'. + +`se' + Used in GDB. + +`sentence-regexp' + `-S' in `ptx'. + +`separate-dirs' + `-S' in `du'. + +`separator' + `-s' in `tac'. + +`sequence' + Used by `recode' to chose files or pipes for sequencing passes. + +`shell' + `-s' in `su'. + +`show-all' + `-A' in `cat'. + +`show-c-function' + `-p' in `diff'. + +`show-ends' + `-E' in `cat'. + +`show-function-line' + `-F' in `diff'. + +`show-tabs' + `-T' in `cat'. + +`silent' + Used in many programs to inhibit the usual output. Every program + accepting `--silent' should accept `--quiet' as a synonym. + +`size' + `-s' in `ls'. + +`socket' + Specify a file descriptor for a network server to use for its + socket, instead of opening and binding a new socket. This + provides a way to run, in a non-privileged process, a server that + normally needs a reserved port number. + +`sort' + Used in `ls'. + +`source' + `-W source' in `gawk'. + +`sparse' + `-S' in `tar'. + +`speed-large-files' + `-H' in `diff'. + +`split-at' + `-E' in `unshar'. + +`split-size-limit' + `-L' in `shar'. + +`squeeze-blank' + `-s' in `cat'. + +`start-delete' + `-w' in `wdiff'. + +`start-insert' + `-y' in `wdiff'. + +`starting-file' + Used in `tar' and `diff' to specify which file within a directory + to start processing with. + +`statistics' + `-s' in `wdiff'. + +`stdin-file-list' + `-S' in `shar'. + +`stop' + `-S' in Make. + +`strict' + `-s' in `recode'. + +`strip' + `-s' in `install'. + +`strip-all' + `-s' in `strip'. + +`strip-debug' + `-S' in `strip'. + +`submitter' + `-s' in `shar'. + +`suffix' + `-S' in `cp', `ln', `mv'. + +`suffix-format' + `-b' in `csplit'. + +`sum' + `-s' in `gprof'. + +`summarize' + `-s' in `du'. + +`symbolic' + `-s' in `ln'. + +`symbols' + Used in GDB and `objdump'. + +`synclines' + `-s' in `m4'. + +`sysname' + `-s' in `uname'. + +`tabs' + `-t' in `expand' and `unexpand'. + +`tabsize' + `-T' in `ls'. + +`terminal' + `-T' in `tput' and `ul'. `-t' in `wdiff'. + +`text' + `-a' in `diff'. + +`text-files' + `-T' in `shar'. + +`time' + Used in `ls' and `touch'. + +`timeout' + Specify how long to wait before giving up on some operation. + +`to-stdout' + `-O' in `tar'. + +`total' + `-c' in `du'. + +`touch' + `-t' in Make, `ranlib', and `recode'. + +`trace' + `-t' in `m4'. + +`traditional' + `-t' in `hello'; `-W traditional' in `gawk'; `-G' in `ed', `m4', + and `ptx'. + +`tty' + Used in GDB. + +`typedefs' + `-t' in `ctags'. + +`typedefs-and-c++' + `-T' in `ctags'. + +`typeset-mode' + `-t' in `ptx'. + +`uncompress' + `-z' in `tar'. + +`unconditional' + `-u' in `cpio'. + +`undefine' + `-U' in `m4'. + +`undefined-only' + `-u' in `nm'. + +`update' + `-u' in `cp', `ctags', `mv', `tar'. + +`usage' + Used in `gawk'; same as `--help'. + +`uuencode' + `-B' in `shar'. + +`vanilla-operation' + `-V' in `shar'. + +`verbose' + Print more information about progress. Many programs support this. + +`verify' + `-W' in `tar'. + +`version' + Print the version number. + +`version-control' + `-V' in `cp', `ln', `mv'. + +`vgrind' + `-v' in `ctags'. + +`volume' + `-V' in `tar'. + +`what-if' + `-W' in Make. + +`whole-size-limit' + `-l' in `shar'. + +`width' + `-w' in `ls' and `ptx'. + +`word-regexp' + `-W' in `ptx'. + +`writable' + `-T' in `who'. + +`zeros' + `-z' in `gprof'. + + +File: standards.info, Node: Memory Usage, Next: File Usage, Prev: Option Table, Up: Program Behavior + +4.9 Memory Usage +================ + +If a program typically uses just a few meg of memory, don't bother +making any effort to reduce memory usage. For example, if it is +impractical for other reasons to operate on files more than a few meg +long, it is reasonable to read entire input files into memory to +operate on them. + + However, for programs such as `cat' or `tail', that can usefully +operate on very large files, it is important to avoid using a technique +that would artificially limit the size of files it can handle. If a +program works by lines and could be applied to arbitrary user-supplied +input files, it should keep only a line in memory, because this is not +very hard and users will want to be able to operate on input files that +are bigger than will fit in memory all at once. + + If your program creates complicated data structures, just make them +in memory and give a fatal error if `malloc' returns zero. + + +File: standards.info, Node: File Usage, Prev: Memory Usage, Up: Program Behavior + +4.10 File Usage +=============== + +Programs should be prepared to operate when `/usr' and `/etc' are +read-only file systems. Thus, if the program manages log files, lock +files, backup files, score files, or any other files which are modified +for internal purposes, these files should not be stored in `/usr' or +`/etc'. + + There are two exceptions. `/etc' is used to store system +configuration information; it is reasonable for a program to modify +files in `/etc' when its job is to update the system configuration. +Also, if the user explicitly asks to modify one file in a directory, it +is reasonable for the program to store other files in the same +directory. + + +File: standards.info, Node: Writing C, Next: Documentation, Prev: Program Behavior, Up: Top + +5 Making The Best Use of C +************************** + +This chapter provides advice on how best to use the C language when +writing GNU software. + +* Menu: + +* Formatting:: Formatting your source code. +* Comments:: Commenting your work. +* Syntactic Conventions:: Clean use of C constructs. +* Names:: Naming variables, functions, and files. +* System Portability:: Portability among different operating systems. +* CPU Portability:: Supporting the range of CPU types. +* System Functions:: Portability and ``standard'' library functions. +* Internationalization:: Techniques for internationalization. +* Character Set:: Use ASCII by default. +* Quote Characters:: Use `...' in the C locale. +* Mmap:: How you can safely use `mmap'. + + +File: standards.info, Node: Formatting, Next: Comments, Up: Writing C + +5.1 Formatting Your Source Code +=============================== + +It is important to put the open-brace that starts the body of a C +function in column one, so that they will start a defun. Several tools +look for open-braces in column one to find the beginnings of C +functions. These tools will not work on code not formatted that way. + + Avoid putting open-brace, open-parenthesis or open-bracket in column +one when they are inside a function, so that they won't start a defun. +The open-brace that starts a `struct' body can go in column one if you +find it useful to treat that definition as a defun. + + It is also important for function definitions to start the name of +the function in column one. This helps people to search for function +definitions, and may also help certain tools recognize them. Thus, +using Standard C syntax, the format is this: + + static char * + concat (char *s1, char *s2) + { + ... + } + +or, if you want to use traditional C syntax, format the definition like +this: + + static char * + concat (s1, s2) /* Name starts in column one here */ + char *s1, *s2; + { /* Open brace in column one here */ + ... + } + + In Standard C, if the arguments don't fit nicely on one line, split +it like this: + + int + lots_of_args (int an_integer, long a_long, short a_short, + double a_double, float a_float) + ... + + The rest of this section gives our recommendations for other aspects +of C formatting style, which is also the default style of the `indent' +program in version 1.2 and newer. It corresponds to the options + + -nbad -bap -nbc -bbo -bl -bli2 -bls -ncdb -nce -cp1 -cs -di2 + -ndj -nfc1 -nfca -hnl -i2 -ip5 -lp -pcs -psl -nsc -nsob + + We don't think of these recommendations as requirements, because it +causes no problems for users if two different programs have different +formatting styles. + + But whatever style you use, please use it consistently, since a +mixture of styles within one program tends to look ugly. If you are +contributing changes to an existing program, please follow the style of +that program. + + For the body of the function, our recommended style looks like this: + + if (x < foo (y, z)) + haha = bar[4] + 5; + else + { + while (z) + { + haha += foo (z, z); + z--; + } + return ++x + bar (); + } + + We find it easier to read a program when it has spaces before the +open-parentheses and after the commas. Especially after the commas. + + When you split an expression into multiple lines, split it before an +operator, not after one. Here is the right way: + + if (foo_this_is_long && bar > win (x, y, z) + && remaining_condition) + + Try to avoid having two operators of different precedence at the same +level of indentation. For example, don't write this: + + mode = (inmode[j] == VOIDmode + || GET_MODE_SIZE (outmode[j]) > GET_MODE_SIZE (inmode[j]) + ? outmode[j] : inmode[j]); + + Instead, use extra parentheses so that the indentation shows the +nesting: + + mode = ((inmode[j] == VOIDmode + || (GET_MODE_SIZE (outmode[j]) > GET_MODE_SIZE (inmode[j]))) + ? outmode[j] : inmode[j]); + + Insert extra parentheses so that Emacs will indent the code properly. +For example, the following indentation looks nice if you do it by hand, + + v = rup->ru_utime.tv_sec*1000 + rup->ru_utime.tv_usec/1000 + + rup->ru_stime.tv_sec*1000 + rup->ru_stime.tv_usec/1000; + +but Emacs would alter it. Adding a set of parentheses produces +something that looks equally nice, and which Emacs will preserve: + + v = (rup->ru_utime.tv_sec*1000 + rup->ru_utime.tv_usec/1000 + + rup->ru_stime.tv_sec*1000 + rup->ru_stime.tv_usec/1000); + + Format do-while statements like this: + + do + { + a = foo (a); + } + while (a > 0); + + Please use formfeed characters (control-L) to divide the program into +pages at logical places (but not within a function). It does not matter +just how long the pages are, since they do not have to fit on a printed +page. The formfeeds should appear alone on lines by themselves. + + +File: standards.info, Node: Comments, Next: Syntactic Conventions, Prev: Formatting, Up: Writing C + +5.2 Commenting Your Work +======================== + +Every program should start with a comment saying briefly what it is for. +Example: `fmt - filter for simple filling of text'. This comment +should be at the top of the source file containing the `main' function +of the program. + + Also, please write a brief comment at the start of each source file, +with the file name and a line or two about the overall purpose of the +file. + + Please write the comments in a GNU program in English, because +English is the one language that nearly all programmers in all +countries can read. If you do not write English well, please write +comments in English as well as you can, then ask other people to help +rewrite them. If you can't write comments in English, please find +someone to work with you and translate your comments into English. + + Please put a comment on each function saying what the function does, +what sorts of arguments it gets, and what the possible values of +arguments mean and are used for. It is not necessary to duplicate in +words the meaning of the C argument declarations, if a C type is being +used in its customary fashion. If there is anything nonstandard about +its use (such as an argument of type `char *' which is really the +address of the second character of a string, not the first), or any +possible values that would not work the way one would expect (such as, +that strings containing newlines are not guaranteed to work), be sure +to say so. + + Also explain the significance of the return value, if there is one. + + Please put two spaces after the end of a sentence in your comments, +so that the Emacs sentence commands will work. Also, please write +complete sentences and capitalize the first word. If a lower-case +identifier comes at the beginning of a sentence, don't capitalize it! +Changing the spelling makes it a different identifier. If you don't +like starting a sentence with a lower case letter, write the sentence +differently (e.g., "The identifier lower-case is ..."). + + The comment on a function is much clearer if you use the argument +names to speak about the argument values. The variable name itself +should be lower case, but write it in upper case when you are speaking +about the value rather than the variable itself. Thus, "the inode +number NODE_NUM" rather than "an inode". + + There is usually no purpose in restating the name of the function in +the comment before it, because the reader can see that for himself. +There might be an exception when the comment is so long that the +function itself would be off the bottom of the screen. + + There should be a comment on each static variable as well, like this: + + /* Nonzero means truncate lines in the display; + zero means continue them. */ + int truncate_lines; + + Every `#endif' should have a comment, except in the case of short +conditionals (just a few lines) that are not nested. The comment should +state the condition of the conditional that is ending, _including its +sense_. `#else' should have a comment describing the condition _and +sense_ of the code that follows. For example: + + #ifdef foo + ... + #else /* not foo */ + ... + #endif /* not foo */ + #ifdef foo + ... + #endif /* foo */ + +but, by contrast, write the comments this way for a `#ifndef': + + #ifndef foo + ... + #else /* foo */ + ... + #endif /* foo */ + #ifndef foo + ... + #endif /* not foo */ + + +File: standards.info, Node: Syntactic Conventions, Next: Names, Prev: Comments, Up: Writing C + +5.3 Clean Use of C Constructs +============================= + +Please explicitly declare the types of all objects. For example, you +should explicitly declare all arguments to functions, and you should +declare functions to return `int' rather than omitting the `int'. + + Some programmers like to use the GCC `-Wall' option, and change the +code whenever it issues a warning. If you want to do this, then do. +Other programmers prefer not to use `-Wall', because it gives warnings +for valid and legitimate code which they do not want to change. If you +want to do this, then do. The compiler should be your servant, not +your master. + + Declarations of external functions and functions to appear later in +the source file should all go in one place near the beginning of the +file (somewhere before the first function definition in the file), or +else should go in a header file. Don't put `extern' declarations inside +functions. + + It used to be common practice to use the same local variables (with +names like `tem') over and over for different values within one +function. Instead of doing this, it is better to declare a separate +local variable for each distinct purpose, and give it a name which is +meaningful. This not only makes programs easier to understand, it also +facilitates optimization by good compilers. You can also move the +declaration of each local variable into the smallest scope that includes +all its uses. This makes the program even cleaner. + + Don't use local variables or parameters that shadow global +identifiers. + + Don't declare multiple variables in one declaration that spans lines. +Start a new declaration on each line, instead. For example, instead of +this: + + int foo, + bar; + +write either this: + + int foo, bar; + +or this: + + int foo; + int bar; + +(If they are global variables, each should have a comment preceding it +anyway.) + + When you have an `if'-`else' statement nested in another `if' +statement, always put braces around the `if'-`else'. Thus, never write +like this: + + if (foo) + if (bar) + win (); + else + lose (); + +always like this: + + if (foo) + { + if (bar) + win (); + else + lose (); + } + + If you have an `if' statement nested inside of an `else' statement, +either write `else if' on one line, like this, + + if (foo) + ... + else if (bar) + ... + +with its `then'-part indented like the preceding `then'-part, or write +the nested `if' within braces like this: + + if (foo) + ... + else + { + if (bar) + ... + } + + Don't declare both a structure tag and variables or typedefs in the +same declaration. Instead, declare the structure tag separately and +then use it to declare the variables or typedefs. + + Try to avoid assignments inside `if'-conditions (assignments inside +`while'-conditions are ok). For example, don't write this: + + if ((foo = (char *) malloc (sizeof *foo)) == 0) + fatal ("virtual memory exhausted"); + +instead, write this: + + foo = (char *) malloc (sizeof *foo); + if (foo == 0) + fatal ("virtual memory exhausted"); + + Don't make the program ugly to placate `lint'. Please don't insert +any casts to `void'. Zero without a cast is perfectly fine as a null +pointer constant, except when calling a varargs function. + + +File: standards.info, Node: Names, Next: System Portability, Prev: Syntactic Conventions, Up: Writing C + +5.4 Naming Variables, Functions, and Files +========================================== + +The names of global variables and functions in a program serve as +comments of a sort. So don't choose terse names--instead, look for +names that give useful information about the meaning of the variable or +function. In a GNU program, names should be English, like other +comments. + + Local variable names can be shorter, because they are used only +within one context, where (presumably) comments explain their purpose. + + Try to limit your use of abbreviations in symbol names. It is ok to +make a few abbreviations, explain what they mean, and then use them +frequently, but don't use lots of obscure abbreviations. + + Please use underscores to separate words in a name, so that the Emacs +word commands can be useful within them. Stick to lower case; reserve +upper case for macros and `enum' constants, and for name-prefixes that +follow a uniform convention. + + For example, you should use names like `ignore_space_change_flag'; +don't use names like `iCantReadThis'. + + Variables that indicate whether command-line options have been +specified should be named after the meaning of the option, not after +the option-letter. A comment should state both the exact meaning of +the option and its letter. For example, + + /* Ignore changes in horizontal whitespace (-b). */ + int ignore_space_change_flag; + + When you want to define names with constant integer values, use +`enum' rather than `#define'. GDB knows about enumeration constants. + + You might want to make sure that none of the file names would +conflict if the files were loaded onto an MS-DOS file system which +shortens the names. You can use the program `doschk' to test for this. + + Some GNU programs were designed to limit themselves to file names of +14 characters or less, to avoid file name conflicts if they are read +into older System V systems. Please preserve this feature in the +existing GNU programs that have it, but there is no need to do this in +new GNU programs. `doschk' also reports file names longer than 14 +characters. + + +File: standards.info, Node: System Portability, Next: CPU Portability, Prev: Names, Up: Writing C + +5.5 Portability between System Types +==================================== + +In the Unix world, "portability" refers to porting to different Unix +versions. For a GNU program, this kind of portability is desirable, but +not paramount. + + The primary purpose of GNU software is to run on top of the GNU +kernel, compiled with the GNU C compiler, on various types of CPU. So +the kinds of portability that are absolutely necessary are quite +limited. But it is important to support Linux-based GNU systems, since +they are the form of GNU that is popular. + + Beyond that, it is good to support the other free operating systems +(*BSD), and it is nice to support other Unix-like systems if you want +to. Supporting a variety of Unix-like systems is desirable, although +not paramount. It is usually not too hard, so you may as well do it. +But you don't have to consider it an obligation, if it does turn out to +be hard. + + The easiest way to achieve portability to most Unix-like systems is +to use Autoconf. It's unlikely that your program needs to know more +information about the host platform than Autoconf can provide, simply +because most of the programs that need such knowledge have already been +written. + + Avoid using the format of semi-internal data bases (e.g., +directories) when there is a higher-level alternative (`readdir'). + + As for systems that are not like Unix, such as MSDOS, Windows, VMS, +MVS, and older Macintosh systems, supporting them is often a lot of +work. When that is the case, it is better to spend your time adding +features that will be useful on GNU and GNU/Linux, rather than on +supporting other incompatible systems. + + If you do support Windows, please do not abbreviate it as "win". In +hacker terminology, calling something a "win" is a form of praise. +You're free to praise Microsoft Windows on your own if you want, but +please don't do this in GNU packages. Instead of abbreviating +"Windows" to "un", you can write it in full or abbreviate it to "woe" +or "w". In GNU Emacs, for instance, we use `w32' in file names of +Windows-specific files, but the macro for Windows conditionals is +called `WINDOWSNT'. + + It is a good idea to define the "feature test macro" `_GNU_SOURCE' +when compiling your C files. When you compile on GNU or GNU/Linux, +this will enable the declarations of GNU library extension functions, +and that will usually give you a compiler error message if you define +the same function names in some other way in your program. (You don't +have to actually _use_ these functions, if you prefer to make the +program more portable to other systems.) + + But whether or not you use these GNU extensions, you should avoid +using their names for any other meanings. Doing so would make it hard +to move your code into other GNU programs. + + +File: standards.info, Node: CPU Portability, Next: System Functions, Prev: System Portability, Up: Writing C + +5.6 Portability between CPUs +============================ + +Even GNU systems will differ because of differences among CPU +types--for example, difference in byte ordering and alignment +requirements. It is absolutely essential to handle these differences. +However, don't make any effort to cater to the possibility that an +`int' will be less than 32 bits. We don't support 16-bit machines in +GNU. + + Similarly, don't make any effort to cater to the possibility that +`long' will be smaller than predefined types like `size_t'. For +example, the following code is ok: + + printf ("size = %lu\n", (unsigned long) sizeof array); + printf ("diff = %ld\n", (long) (pointer2 - pointer1)); + + 1989 Standard C requires this to work, and we know of only one +counterexample: 64-bit programs on Microsoft Windows. We will leave it +to those who want to port GNU programs to that environment to figure +out how to do it. + + Predefined file-size types like `off_t' are an exception: they are +longer than `long' on many platforms, so code like the above won't work +with them. One way to print an `off_t' value portably is to print its +digits yourself, one by one. + + Don't assume that the address of an `int' object is also the address +of its least-significant byte. This is false on big-endian machines. +Thus, don't make the following mistake: + + int c; + ... + while ((c = getchar ()) != EOF) + write (file_descriptor, &c, 1); + +Instead, use `unsigned char' as follows. (The `unsigned' is for +portability to unusual systems where `char' is signed and where there +is integer overflow checking.) + + int c; + while ((c = getchar ()) != EOF) + { + unsigned char u = c; + write (file_descriptor, &u, 1); + } + + It used to be ok to not worry about the difference between pointers +and integers when passing arguments to functions. However, on most +modern 64-bit machines pointers are wider than `int'. Conversely, +integer types like `long long int' and `off_t' are wider than pointers +on most modern 32-bit machines. Hence it's often better nowadays to +use prototypes to define functions whose argument types are not trivial. + + In particular, if functions accept varying argument counts or types +they should be declared using prototypes containing `...' and defined +using `stdarg.h'. For an example of this, please see the Gnulib +(http://www.gnu.org/software/gnulib/) error module, which declares and +defines the following function: + + /* Print a message with `fprintf (stderr, FORMAT, ...)'; + if ERRNUM is nonzero, follow it with ": " and strerror (ERRNUM). + If STATUS is nonzero, terminate the program with `exit (STATUS)'. */ + + void error (int status, int errnum, const char *format, ...); + + A simple way to use the Gnulib error module is to obtain the two +source files `error.c' and `error.h' from the Gnulib library source +code repository at +`http://savannah.gnu.org/cgi-bin/viewcvs/gnulib/gnulib/lib/'. Here's a +sample use: + + #include "error.h" + #include <errno.h> + #include <stdio.h> + + char *program_name = "myprogram"; + + FILE * + xfopen (char const *name) + { + FILE *fp = fopen (name, "r"); + if (! fp) + error (1, errno, "cannot read %s", name); + return fp; + } + + Avoid casting pointers to integers if you can. Such casts greatly +reduce portability, and in most programs they are easy to avoid. In the +cases where casting pointers to integers is essential--such as, a Lisp +interpreter which stores type information as well as an address in one +word--you'll have to make explicit provisions to handle different word +sizes. You will also need to make provision for systems in which the +normal range of addresses you can get from `malloc' starts far away +from zero. + + +File: standards.info, Node: System Functions, Next: Internationalization, Prev: CPU Portability, Up: Writing C + +5.7 Calling System Functions +============================ + +C implementations differ substantially. Standard C reduces but does +not eliminate the incompatibilities; meanwhile, many GNU packages still +support pre-standard compilers because this is not hard to do. This +chapter gives recommendations for how to use the more-or-less standard C +library functions to avoid unnecessary loss of portability. + + * Don't use the return value of `sprintf'. It returns the number of + characters written on some systems, but not on all systems. + + * Be aware that `vfprintf' is not always available. + + * `main' should be declared to return type `int'. It should + terminate either by calling `exit' or by returning the integer + status code; make sure it cannot ever return an undefined value. + + * Don't declare system functions explicitly. + + Almost any declaration for a system function is wrong on some + system. To minimize conflicts, leave it to the system header + files to declare system functions. If the headers don't declare a + function, let it remain undeclared. + + While it may seem unclean to use a function without declaring it, + in practice this works fine for most system library functions on + the systems where this really happens; thus, the disadvantage is + only theoretical. By contrast, actual declarations have + frequently caused actual conflicts. + + * If you must declare a system function, don't specify the argument + types. Use an old-style declaration, not a Standard C prototype. + The more you specify about the function, the more likely a + conflict. + + * In particular, don't unconditionally declare `malloc' or `realloc'. + + Most GNU programs use those functions just once, in functions + conventionally named `xmalloc' and `xrealloc'. These functions + call `malloc' and `realloc', respectively, and check the results. + + Because `xmalloc' and `xrealloc' are defined in your program, you + can declare them in other files without any risk of type conflict. + + On most systems, `int' is the same length as a pointer; thus, the + calls to `malloc' and `realloc' work fine. For the few + exceptional systems (mostly 64-bit machines), you can use + *conditionalized* declarations of `malloc' and `realloc'--or put + these declarations in configuration files specific to those + systems. + + * The string functions require special treatment. Some Unix systems + have a header file `string.h'; others have `strings.h'. Neither + file name is portable. There are two things you can do: use + Autoconf to figure out which file to include, or don't include + either file. + + * If you don't include either strings file, you can't get + declarations for the string functions from the header file in the + usual way. + + That causes less of a problem than you might think. The newer + standard string functions should be avoided anyway because many + systems still don't support them. The string functions you can + use are these: + + strcpy strncpy strcat strncat + strlen strcmp strncmp + strchr strrchr + + The copy and concatenate functions work fine without a declaration + as long as you don't use their values. Using their values without + a declaration fails on systems where the width of a pointer + differs from the width of `int', and perhaps in other cases. It + is trivial to avoid using their values, so do that. + + The compare functions and `strlen' work fine without a declaration + on most systems, possibly all the ones that GNU software runs on. + You may find it necessary to declare them *conditionally* on a few + systems. + + The search functions must be declared to return `char *'. Luckily, + there is no variation in the data type they return. But there is + variation in their names. Some systems give these functions the + names `index' and `rindex'; other systems use the names `strchr' + and `strrchr'. Some systems support both pairs of names, but + neither pair works on all systems. + + You should pick a single pair of names and use it throughout your + program. (Nowadays, it is better to choose `strchr' and `strrchr' + for new programs, since those are the standard names.) Declare + both of those names as functions returning `char *'. On systems + which don't support those names, define them as macros in terms of + the other pair. For example, here is what to put at the beginning + of your file (or in a header) if you want to use the names + `strchr' and `strrchr' throughout: + + #ifndef HAVE_STRCHR + #define strchr index + #endif + #ifndef HAVE_STRRCHR + #define strrchr rindex + #endif + + char *strchr (); + char *strrchr (); + + Here we assume that `HAVE_STRCHR' and `HAVE_STRRCHR' are macros +defined in systems where the corresponding functions exist. One way to +get them properly defined is to use Autoconf. + + +File: standards.info, Node: Internationalization, Next: Character Set, Prev: System Functions, Up: Writing C + +5.8 Internationalization +======================== + +GNU has a library called GNU gettext that makes it easy to translate the +messages in a program into various languages. You should use this +library in every program. Use English for the messages as they appear +in the program, and let gettext provide the way to translate them into +other languages. + + Using GNU gettext involves putting a call to the `gettext' macro +around each string that might need translation--like this: + + printf (gettext ("Processing file `%s'...")); + +This permits GNU gettext to replace the string `"Processing file +`%s'..."' with a translated version. + + Once a program uses gettext, please make a point of writing calls to +`gettext' when you add new strings that call for translation. + + Using GNU gettext in a package involves specifying a "text domain +name" for the package. The text domain name is used to separate the +translations for this package from the translations for other packages. +Normally, the text domain name should be the same as the name of the +package--for example, `coreutils' for the GNU core utilities. + + To enable gettext to work well, avoid writing code that makes +assumptions about the structure of words or sentences. When you want +the precise text of a sentence to vary depending on the data, use two or +more alternative string constants each containing a complete sentences, +rather than inserting conditionalized words or phrases into a single +sentence framework. + + Here is an example of what not to do: + + printf ("%s is full", capacity > 5000000 ? "disk" : "floppy disk"); + + If you apply gettext to all strings, like this, + + printf (gettext ("%s is full"), + capacity > 5000000 ? gettext ("disk") : gettext ("floppy disk")); + +the translator will hardly know that "disk" and "floppy disk" are meant +to be substituted in the other string. Worse, in some languages (like +French) the construction will not work: the translation of the word +"full" depends on the gender of the first part of the sentence; it +happens to be not the same for "disk" as for "floppy disk". + + Complete sentences can be translated without problems: + + printf (capacity > 5000000 ? gettext ("disk is full") + : gettext ("floppy disk is full")); + + A similar problem appears at the level of sentence structure with +this code: + + printf ("# Implicit rule search has%s been done.\n", + f->tried_implicit ? "" : " not"); + +Adding `gettext' calls to this code cannot give correct results for all +languages, because negation in some languages requires adding words at +more than one place in the sentence. By contrast, adding `gettext' +calls does the job straightforwardly if the code starts out like this: + + printf (f->tried_implicit + ? "# Implicit rule search has been done.\n", + : "# Implicit rule search has not been done.\n"); + + Another example is this one: + + printf ("%d file%s processed", nfiles, + nfiles != 1 ? "s" : ""); + +The problem with this example is that it assumes that plurals are made +by adding `s'. If you apply gettext to the format string, like this, + + printf (gettext ("%d file%s processed"), nfiles, + nfiles != 1 ? "s" : ""); + +the message can use different words, but it will still be forced to use +`s' for the plural. Here is a better way, with gettext being applied to +the two strings independently: + + printf ((nfiles != 1 ? gettext ("%d files processed") + : gettext ("%d file processed")), + nfiles); + +But this still doesn't work for languages like Polish, which has three +plural forms: one for nfiles == 1, one for nfiles == 2, 3, 4, 22, 23, +24, ... and one for the rest. The GNU `ngettext' function solves this +problem: + + printf (ngettext ("%d files processed", "%d file processed", nfiles), + nfiles); + + +File: standards.info, Node: Character Set, Next: Quote Characters, Prev: Internationalization, Up: Writing C + +5.9 Character Set +================= + +Sticking to the ASCII character set (plain text, 7-bit characters) is +preferred in GNU source code comments, text documents, and other +contexts, unless there is good reason to do something else because of +the application domain. For example, if source code deals with the +French Revolutionary calendar, it is OK if its literal strings contain +accented characters in month names like "Flore'al". Also, it is OK to +use non-ASCII characters to represent proper names of contributors in +change logs (*note Change Logs::). + + If you need to use non-ASCII characters, you should normally stick +with one encoding, as one cannot in general mix encodings reliably. + + +File: standards.info, Node: Quote Characters, Next: Mmap, Prev: Character Set, Up: Writing C + +5.10 Quote Characters +===================== + +In the C locale, GNU programs should stick to plain ASCII for quotation +characters in messages to users: preferably 0x60 (``') for left quotes +and 0x27 (`'') for right quotes. It is ok, but not required, to use +locale-specific quotes in other locales. + + The Gnulib (http://www.gnu.org/software/gnulib/) `quote' and +`quotearg' modules provide a reasonably straightforward way to support +locale-specific quote characters, as well as taking care of other +issues, such as quoting a filename that itself contains a quote +character. See the Gnulib documentation for usage details. + + In any case, the documentation for your program should clearly +specify how it does quoting, if different than the preferred method of +``' and `''. This is especially important if the output of your +program is ever likely to be parsed by another program. + + Quotation characters are a difficult area in the computing world at +this time: there are no true left or right quote characters in Latin1; +the ``' character we use was standardized there as a grave accent. +Moreover, Latin1 is still not universally usable. + + Unicode contains the unambiguous quote characters required, and its +common encoding UTF-8 is upward compatible with Latin1. However, +Unicode and UTF-8 are not universally well-supported, either. + + This may change over the next few years, and then we will revisit +this. + + +File: standards.info, Node: Mmap, Prev: Quote Characters, Up: Writing C + +5.11 Mmap +========= + +Don't assume that `mmap' either works on all files or fails for all +files. It may work on some files and fail on others. + + The proper way to use `mmap' is to try it on the specific file for +which you want to use it--and if `mmap' doesn't work, fall back on +doing the job in another way using `read' and `write'. + + The reason this precaution is needed is that the GNU kernel (the +HURD) provides a user-extensible file system, in which there can be many +different kinds of "ordinary files." Many of them support `mmap', but +some do not. It is important to make programs handle all these kinds +of files. + + +File: standards.info, Node: Documentation, Next: Managing Releases, Prev: Writing C, Up: Top + +6 Documenting Programs +********************** + +A GNU program should ideally come with full free documentation, adequate +for both reference and tutorial purposes. If the package can be +programmed or extended, the documentation should cover programming or +extending it, as well as just using it. + +* Menu: + +* GNU Manuals:: Writing proper manuals. +* Doc Strings and Manuals:: Compiling doc strings doesn't make a manual. +* Manual Structure Details:: Specific structure conventions. +* License for Manuals:: Writing the distribution terms for a manual. +* Manual Credits:: Giving credit to documentation contributors. +* Printed Manuals:: Mentioning the printed manual. +* NEWS File:: NEWS files supplement manuals. +* Change Logs:: Recording changes. +* Man Pages:: Man pages are secondary. +* Reading other Manuals:: How far you can go in learning + from other manuals. + + +File: standards.info, Node: GNU Manuals, Next: Doc Strings and Manuals, Up: Documentation + +6.1 GNU Manuals +=============== + +The preferred document format for the GNU system is the Texinfo +formatting language. Every GNU package should (ideally) have +documentation in Texinfo both for reference and for learners. Texinfo +makes it possible to produce a good quality formatted book, using TeX, +and to generate an Info file. It is also possible to generate HTML +output from Texinfo source. See the Texinfo manual, either the +hardcopy, or the on-line version available through `info' or the Emacs +Info subsystem (`C-h i'). + + Nowadays some other formats such as Docbook and Sgmltexi can be +converted automatically into Texinfo. It is ok to produce the Texinfo +documentation by conversion this way, as long as it gives good results. + + Make sure your manual is clear to a reader who knows nothing about +the topic and reads it straight through. This means covering basic +topics at the beginning, and advanced topics only later. This also +means defining every specialized term when it is first used. + + Programmers tend to carry over the structure of the program as the +structure for its documentation. But this structure is not necessarily +good for explaining how to use the program; it may be irrelevant and +confusing for a user. + + Instead, the right way to structure documentation is according to the +concepts and questions that a user will have in mind when reading it. +This principle applies at every level, from the lowest (ordering +sentences in a paragraph) to the highest (ordering of chapter topics +within the manual). Sometimes this structure of ideas matches the +structure of the implementation of the software being documented--but +often they are different. An important part of learning to write good +documentation is to learn to notice when you have unthinkingly +structured the documentation like the implementation, stop yourself, +and look for better alternatives. + + For example, each program in the GNU system probably ought to be +documented in one manual; but this does not mean each program should +have its own manual. That would be following the structure of the +implementation, rather than the structure that helps the user +understand. + + Instead, each manual should cover a coherent _topic_. For example, +instead of a manual for `diff' and a manual for `diff3', we have one +manual for "comparison of files" which covers both of those programs, +as well as `cmp'. By documenting these programs together, we can make +the whole subject clearer. + + The manual which discusses a program should certainly document all of +the program's command-line options and all of its commands. It should +give examples of their use. But don't organize the manual as a list of +features. Instead, organize it logically, by subtopics. Address the +questions that a user will ask when thinking about the job that the +program does. Don't just tell the reader what each feature can do--say +what jobs it is good for, and show how to use it for those jobs. +Explain what is recommended usage, and what kinds of usage users should +avoid. + + In general, a GNU manual should serve both as tutorial and reference. +It should be set up for convenient access to each topic through Info, +and for reading straight through (appendixes aside). A GNU manual +should give a good introduction to a beginner reading through from the +start, and should also provide all the details that hackers want. The +Bison manual is a good example of this--please take a look at it to see +what we mean. + + That is not as hard as it first sounds. Arrange each chapter as a +logical breakdown of its topic, but order the sections, and write their +text, so that reading the chapter straight through makes sense. Do +likewise when structuring the book into chapters, and when structuring a +section into paragraphs. The watchword is, _at each point, address the +most fundamental and important issue raised by the preceding text._ + + If necessary, add extra chapters at the beginning of the manual which +are purely tutorial and cover the basics of the subject. These provide +the framework for a beginner to understand the rest of the manual. The +Bison manual provides a good example of how to do this. + + To serve as a reference, a manual should have an Index that list all +the functions, variables, options, and important concepts that are part +of the program. One combined Index should do for a short manual, but +sometimes for a complex package it is better to use multiple indices. +The Texinfo manual includes advice on preparing good index entries, see +*Note Making Index Entries: (texinfo)Index Entries, and see *Note +Defining the Entries of an Index: (texinfo)Indexing Commands. + + Don't use Unix man pages as a model for how to write GNU +documentation; most of them are terse, badly structured, and give +inadequate explanation of the underlying concepts. (There are, of +course, some exceptions.) Also, Unix man pages use a particular format +which is different from what we use in GNU manuals. + + Please include an email address in the manual for where to report +bugs _in the text of the manual_. + + Please do not use the term "pathname" that is used in Unix +documentation; use "file name" (two words) instead. We use the term +"path" only for search paths, which are lists of directory names. + + Please do not use the term "illegal" to refer to erroneous input to +a computer program. Please use "invalid" for this, and reserve the +term "illegal" for activities prohibited by law. + + Please do not write `()' after a function name just to indicate it +is a function. `foo ()' is not a function, it is a function call with +no arguments. + + +File: standards.info, Node: Doc Strings and Manuals, Next: Manual Structure Details, Prev: GNU Manuals, Up: Documentation + +6.2 Doc Strings and Manuals +=========================== + +Some programming systems, such as Emacs, provide a documentation string +for each function, command or variable. You may be tempted to write a +reference manual by compiling the documentation strings and writing a +little additional text to go around them--but you must not do it. That +approach is a fundamental mistake. The text of well-written +documentation strings will be entirely wrong for a manual. + + A documentation string needs to stand alone--when it appears on the +screen, there will be no other text to introduce or explain it. +Meanwhile, it can be rather informal in style. + + The text describing a function or variable in a manual must not stand +alone; it appears in the context of a section or subsection. Other text +at the beginning of the section should explain some of the concepts, and +should often make some general points that apply to several functions or +variables. The previous descriptions of functions and variables in the +section will also have given information about the topic. A description +written to stand alone would repeat some of that information; this +redundancy looks bad. Meanwhile, the informality that is acceptable in +a documentation string is totally unacceptable in a manual. + + The only good way to use documentation strings in writing a good +manual is to use them as a source of information for writing good text. + + +File: standards.info, Node: Manual Structure Details, Next: License for Manuals, Prev: Doc Strings and Manuals, Up: Documentation + +6.3 Manual Structure Details +============================ + +The title page of the manual should state the version of the programs or +packages documented in the manual. The Top node of the manual should +also contain this information. If the manual is changing more +frequently than or independent of the program, also state a version +number for the manual in both of these places. + + Each program documented in the manual should have a node named +`PROGRAM Invocation' or `Invoking PROGRAM'. This node (together with +its subnodes, if any) should describe the program's command line +arguments and how to run it (the sort of information people would look +for in a man page). Start with an `@example' containing a template for +all the options and arguments that the program uses. + + Alternatively, put a menu item in some menu whose item name fits one +of the above patterns. This identifies the node which that item points +to as the node for this purpose, regardless of the node's actual name. + + The `--usage' feature of the Info reader looks for such a node or +menu item in order to find the relevant text, so it is essential for +every Texinfo file to have one. + + If one manual describes several programs, it should have such a node +for each program described in the manual. + + +File: standards.info, Node: License for Manuals, Next: Manual Credits, Prev: Manual Structure Details, Up: Documentation + +6.4 License for Manuals +======================= + +Please use the GNU Free Documentation License for all GNU manuals that +are more than a few pages long. Likewise for a collection of short +documents--you only need one copy of the GNU FDL for the whole +collection. For a single short document, you can use a very permissive +non-copyleft license, to avoid taking up space with a long license. + + See `http://www.gnu.org/copyleft/fdl-howto.html' for more explanation +of how to employ the GFDL. + + Note that it is not obligatory to include a copy of the GNU GPL or +GNU LGPL in a manual whose license is neither the GPL nor the LGPL. It +can be a good idea to include the program's license in a large manual; +in a short manual, whose size would be increased considerably by +including the program's license, it is probably better not to include +it. + + +File: standards.info, Node: Manual Credits, Next: Printed Manuals, Prev: License for Manuals, Up: Documentation + +6.5 Manual Credits +================== + +Please credit the principal human writers of the manual as the authors, +on the title page of the manual. If a company sponsored the work, thank +the company in a suitable place in the manual, but do not cite the +company as an author. + + +File: standards.info, Node: Printed Manuals, Next: NEWS File, Prev: Manual Credits, Up: Documentation + +6.6 Printed Manuals +=================== + +The FSF publishes some GNU manuals in printed form. To encourage sales +of these manuals, the on-line versions of the manual should mention at +the very start that the printed manual is available and should point at +information for getting it--for instance, with a link to the page +`http://www.gnu.org/order/order.html'. This should not be included in +the printed manual, though, because there it is redundant. + + It is also useful to explain in the on-line forms of the manual how +the user can print out the manual from the sources. + + +File: standards.info, Node: NEWS File, Next: Change Logs, Prev: Printed Manuals, Up: Documentation + +6.7 The NEWS File +================= + +In addition to its manual, the package should have a file named `NEWS' +which contains a list of user-visible changes worth mentioning. In +each new release, add items to the front of the file and identify the +version they pertain to. Don't discard old items; leave them in the +file after the newer items. This way, a user upgrading from any +previous version can see what is new. + + If the `NEWS' file gets very long, move some of the older items into +a file named `ONEWS' and put a note at the end referring the user to +that file. + + +File: standards.info, Node: Change Logs, Next: Man Pages, Prev: NEWS File, Up: Documentation + +6.8 Change Logs +=============== + +Keep a change log to describe all the changes made to program source +files. The purpose of this is so that people investigating bugs in the +future will know about the changes that might have introduced the bug. +Often a new bug can be found by looking at what was recently changed. +More importantly, change logs can help you eliminate conceptual +inconsistencies between different parts of a program, by giving you a +history of how the conflicting concepts arose and who they came from. + +* Menu: + +* Change Log Concepts:: +* Style of Change Logs:: +* Simple Changes:: +* Conditional Changes:: +* Indicating the Part Changed:: + + +File: standards.info, Node: Change Log Concepts, Next: Style of Change Logs, Up: Change Logs + +6.8.1 Change Log Concepts +------------------------- + +You can think of the change log as a conceptual "undo list" which +explains how earlier versions were different from the current version. +People can see the current version; they don't need the change log to +tell them what is in it. What they want from a change log is a clear +explanation of how the earlier version differed. + + The change log file is normally called `ChangeLog' and covers an +entire directory. Each directory can have its own change log, or a +directory can use the change log of its parent directory-it's up to you. + + Another alternative is to record change log information with a +version control system such as RCS or CVS. This can be converted +automatically to a `ChangeLog' file using `rcs2log'; in Emacs, the +command `C-x v a' (`vc-update-change-log') does the job. + + There's no need to describe the full purpose of the changes or how +they work together. If you think that a change calls for explanation, +you're probably right. Please do explain it--but please put the +explanation in comments in the code, where people will see it whenever +they see the code. For example, "New function" is enough for the +change log when you add a function, because there should be a comment +before the function definition to explain what it does. + + In the past, we recommended not mentioning changes in non-software +files (manuals, help files, etc.) in change logs. However, we've been +advised that it is a good idea to include them, for the sake of +copyright records. + + However, sometimes it is useful to write one line to describe the +overall purpose of a batch of changes. + + The easiest way to add an entry to `ChangeLog' is with the Emacs +command `M-x add-change-log-entry'. An entry should have an asterisk, +the name of the changed file, and then in parentheses the name of the +changed functions, variables or whatever, followed by a colon. Then +describe the changes you made to that function or variable. + + +File: standards.info, Node: Style of Change Logs, Next: Simple Changes, Prev: Change Log Concepts, Up: Change Logs + +6.8.2 Style of Change Logs +-------------------------- + +Here are some simple examples of change log entries, starting with the +header line that says who made the change and when it was installed, +followed by descriptions of specific changes. (These examples are +drawn from Emacs and GCC.) + + 1998-08-17 Richard Stallman <rms@gnu.org> + + * register.el (insert-register): Return nil. + (jump-to-register): Likewise. + + * sort.el (sort-subr): Return nil. + + * tex-mode.el (tex-bibtex-file, tex-file, tex-region): + Restart the tex shell if process is gone or stopped. + (tex-shell-running): New function. + + * expr.c (store_one_arg): Round size up for move_block_to_reg. + (expand_call): Round up when emitting USE insns. + * stmt.c (assign_parms): Round size up for move_block_from_reg. + + It's important to name the changed function or variable in full. +Don't abbreviate function or variable names, and don't combine them. +Subsequent maintainers will often search for a function name to find all +the change log entries that pertain to it; if you abbreviate the name, +they won't find it when they search. + + For example, some people are tempted to abbreviate groups of function +names by writing `* register.el ({insert,jump-to}-register)'; this is +not a good idea, since searching for `jump-to-register' or +`insert-register' would not find that entry. + + Separate unrelated change log entries with blank lines. When two +entries represent parts of the same change, so that they work together, +then don't put blank lines between them. Then you can omit the file +name and the asterisk when successive entries are in the same file. + + Break long lists of function names by closing continued lines with +`)', rather than `,', and opening the continuation with `(' as in this +example: + + * keyboard.c (menu_bar_items, tool_bar_items) + (Fexecute_extended_command): Deal with `keymap' property. + + When you install someone else's changes, put the contributor's name +in the change log entry rather than in the text of the entry. In other +words, write this: + + 2002-07-14 John Doe <jdoe@gnu.org> + + * sewing.c: Make it sew. + +rather than this: + + 2002-07-14 Usual Maintainer <usual@gnu.org> + + * sewing.c: Make it sew. Patch by jdoe@gnu.org. + + As for the date, that should be the date you applied the change. + + +File: standards.info, Node: Simple Changes, Next: Conditional Changes, Prev: Style of Change Logs, Up: Change Logs + +6.8.3 Simple Changes +-------------------- + +Certain simple kinds of changes don't need much detail in the change +log. + + When you change the calling sequence of a function in a simple +fashion, and you change all the callers of the function to use the new +calling sequence, there is no need to make individual entries for all +the callers that you changed. Just write in the entry for the function +being called, "All callers changed"--like this: + + * keyboard.c (Fcommand_execute): New arg SPECIAL. + All callers changed. + + When you change just comments or doc strings, it is enough to write +an entry for the file, without mentioning the functions. Just "Doc +fixes" is enough for the change log. + + There's no technical need to make change log entries for +documentation files. This is because documentation is not susceptible +to bugs that are hard to fix. Documentation does not consist of parts +that must interact in a precisely engineered fashion. To correct an +error, you need not know the history of the erroneous passage; it is +enough to compare what the documentation says with the way the program +actually works. + + However, you should keep change logs for documentation files when the +project gets copyright assignments from its contributors, so as to make +the records of authorship more accurate. + + +File: standards.info, Node: Conditional Changes, Next: Indicating the Part Changed, Prev: Simple Changes, Up: Change Logs + +6.8.4 Conditional Changes +------------------------- + +C programs often contain compile-time `#if' conditionals. Many changes +are conditional; sometimes you add a new definition which is entirely +contained in a conditional. It is very useful to indicate in the +change log the conditions for which the change applies. + + Our convention for indicating conditional changes is to use square +brackets around the name of the condition. + + Here is a simple example, describing a change which is conditional +but does not have a function or entity name associated with it: + + * xterm.c [SOLARIS2]: Include string.h. + + Here is an entry describing a new definition which is entirely +conditional. This new definition for the macro `FRAME_WINDOW_P' is +used only when `HAVE_X_WINDOWS' is defined: + + * frame.h [HAVE_X_WINDOWS] (FRAME_WINDOW_P): Macro defined. + + Here is an entry for a change within the function `init_display', +whose definition as a whole is unconditional, but the changes themselves +are contained in a `#ifdef HAVE_LIBNCURSES' conditional: + + * dispnew.c (init_display) [HAVE_LIBNCURSES]: If X, call tgetent. + + Here is an entry for a change that takes affect only when a certain +macro is _not_ defined: + + (gethostname) [!HAVE_SOCKETS]: Replace with winsock version. + + +File: standards.info, Node: Indicating the Part Changed, Prev: Conditional Changes, Up: Change Logs + +6.8.5 Indicating the Part Changed +--------------------------------- + +Indicate the part of a function which changed by using angle brackets +enclosing an indication of what the changed part does. Here is an entry +for a change in the part of the function `sh-while-getopts' that deals +with `sh' commands: + + * progmodes/sh-script.el (sh-while-getopts) <sh>: Handle case that + user-specified option string is empty. + + +File: standards.info, Node: Man Pages, Next: Reading other Manuals, Prev: Change Logs, Up: Documentation + +6.9 Man Pages +============= + +In the GNU project, man pages are secondary. It is not necessary or +expected for every GNU program to have a man page, but some of them do. +It's your choice whether to include a man page in your program. + + When you make this decision, consider that supporting a man page +requires continual effort each time the program is changed. The time +you spend on the man page is time taken away from more useful work. + + For a simple program which changes little, updating the man page may +be a small job. Then there is little reason not to include a man page, +if you have one. + + For a large program that changes a great deal, updating a man page +may be a substantial burden. If a user offers to donate a man page, +you may find this gift costly to accept. It may be better to refuse +the man page unless the same person agrees to take full responsibility +for maintaining it--so that you can wash your hands of it entirely. If +this volunteer later ceases to do the job, then don't feel obliged to +pick it up yourself; it may be better to withdraw the man page from the +distribution until someone else agrees to update it. + + When a program changes only a little, you may feel that the +discrepancies are small enough that the man page remains useful without +updating. If so, put a prominent note near the beginning of the man +page explaining that you don't maintain it and that the Texinfo manual +is more authoritative. The note should say how to access the Texinfo +documentation. + + Be sure that man pages include a copyright statement and free +license. The simple all-permissive license is appropriate for simple +man pages: + + Copying and distribution of this file, with or without modification, + are permitted in any medium without royalty provided the copyright + notice and this notice are preserved. + + For long man pages, with enough explanation and documentation that +they can be considered true manuals, use the GFDL (*note License for +Manuals::). + + Finally, the GNU help2man program +(`http://www.gnu.org/software/help2man/') is one way to automate +generation of a man page, in this case from `--help' output. This is +sufficient in many cases. + + +File: standards.info, Node: Reading other Manuals, Prev: Man Pages, Up: Documentation + +6.10 Reading other Manuals +========================== + +There may be non-free books or documentation files that describe the +program you are documenting. + + It is ok to use these documents for reference, just as the author of +a new algebra textbook can read other books on algebra. A large portion +of any non-fiction book consists of facts, in this case facts about how +a certain program works, and these facts are necessarily the same for +everyone who writes about the subject. But be careful not to copy your +outline structure, wording, tables or examples from preexisting non-free +documentation. Copying from free documentation may be ok; please check +with the FSF about the individual case. + + +File: standards.info, Node: Managing Releases, Next: References, Prev: Documentation, Up: Top + +7 The Release Process +********************* + +Making a release is more than just bundling up your source files in a +tar file and putting it up for FTP. You should set up your software so +that it can be configured to run on a variety of systems. Your Makefile +should conform to the GNU standards described below, and your directory +layout should also conform to the standards discussed below. Doing so +makes it easy to include your package into the larger framework of all +GNU software. + +* Menu: + +* Configuration:: How configuration of GNU packages should work. +* Makefile Conventions:: Makefile conventions. +* Releases:: Making releases + + +File: standards.info, Node: Configuration, Next: Makefile Conventions, Up: Managing Releases + +7.1 How Configuration Should Work +================================= + +Each GNU distribution should come with a shell script named +`configure'. This script is given arguments which describe the kind of +machine and system you want to compile the program for. + + The `configure' script must record the configuration options so that +they affect compilation. + + One way to do this is to make a link from a standard name such as +`config.h' to the proper configuration file for the chosen system. If +you use this technique, the distribution should _not_ contain a file +named `config.h'. This is so that people won't be able to build the +program without configuring it first. + + Another thing that `configure' can do is to edit the Makefile. If +you do this, the distribution should _not_ contain a file named +`Makefile'. Instead, it should include a file `Makefile.in' which +contains the input used for editing. Once again, this is so that people +won't be able to build the program without configuring it first. + + If `configure' does write the `Makefile', then `Makefile' should +have a target named `Makefile' which causes `configure' to be rerun, +setting up the same configuration that was set up last time. The files +that `configure' reads should be listed as dependencies of `Makefile'. + + All the files which are output from the `configure' script should +have comments at the beginning explaining that they were generated +automatically using `configure'. This is so that users won't think of +trying to edit them by hand. + + The `configure' script should write a file named `config.status' +which describes which configuration options were specified when the +program was last configured. This file should be a shell script which, +if run, will recreate the same configuration. + + The `configure' script should accept an option of the form +`--srcdir=DIRNAME' to specify the directory where sources are found (if +it is not the current directory). This makes it possible to build the +program in a separate directory, so that the actual source directory is +not modified. + + If the user does not specify `--srcdir', then `configure' should +check both `.' and `..' to see if it can find the sources. If it finds +the sources in one of these places, it should use them from there. +Otherwise, it should report that it cannot find the sources, and should +exit with nonzero status. + + Usually the easy way to support `--srcdir' is by editing a +definition of `VPATH' into the Makefile. Some rules may need to refer +explicitly to the specified source directory. To make this possible, +`configure' can add to the Makefile a variable named `srcdir' whose +value is precisely the specified directory. + + The `configure' script should also take an argument which specifies +the type of system to build the program for. This argument should look +like this: + + CPU-COMPANY-SYSTEM + + For example, an Athlon-based GNU/Linux system might be +`i686-pc-linux-gnu'. + + The `configure' script needs to be able to decode all plausible +alternatives for how to describe a machine. Thus, +`athlon-pc-gnu/linux' would be a valid alias. There is a shell script +called `config.sub' +(http://savannah.gnu.org/cgi-bin/viewcvs/*checkout*/config/config/config.sub) +that you can use as a subroutine to validate system types and +canonicalize aliases. + + The `configure' script should also take the option +`--build=BUILDTYPE', which should be equivalent to a plain BUILDTYPE +argument. For example, `configure --build=i686-pc-linux-gnu' is +equivalent to `configure i686-pc-linux-gnu'. When the build type is +not specified by an option or argument, the `configure' script should +normally guess it using the shell script `config.guess' +(http://savannah.gnu.org/cgi-bin/viewcvs/*checkout*/config/config/config.guess). + + Other options are permitted to specify in more detail the software +or hardware present on the machine, to include or exclude optional parts +of the package, or to adjust the name of some tools or arguments to +them: + +`--enable-FEATURE[=PARAMETER]' + Configure the package to build and install an optional user-level + facility called FEATURE. This allows users to choose which + optional features to include. Giving an optional PARAMETER of + `no' should omit FEATURE, if it is built by default. + + No `--enable' option should *ever* cause one feature to replace + another. No `--enable' option should ever substitute one useful + behavior for another useful behavior. The only proper use for + `--enable' is for questions of whether to build part of the program + or exclude it. + +`--with-PACKAGE' + The package PACKAGE will be installed, so configure this package + to work with PACKAGE. + + Possible values of PACKAGE include `gnu-as' (or `gas'), `gnu-ld', + `gnu-libc', `gdb', `x', and `x-toolkit'. + + Do not use a `--with' option to specify the file name to use to + find certain files. That is outside the scope of what `--with' + options are for. + +`VARIABLE=VALUE' + Set the value of the variable VARIABLE to VALUE. This is used to + override the default values of commands or arguments in the build + process. For example, the user could issue `configure CFLAGS=-g + CXXFLAGS=-g' to build with debugging information and without the + default optimization. + + Specifying variables as arguments to `configure', like this: + ./configure CC=gcc + is preferable to setting them in environment variables: + CC=gcc ./configure + as it helps to recreate the same configuration later with + `config.status'. + + All `configure' scripts should accept all of the "detail" options +and the variable settings, whether or not they make any difference to +the particular package at hand. In particular, they should accept any +option that starts with `--with-' or `--enable-'. This is so users +will be able to configure an entire GNU source tree at once with a +single set of options. + + You will note that the categories `--with-' and `--enable-' are +narrow: they *do not* provide a place for any sort of option you might +think of. That is deliberate. We want to limit the possible +configuration options in GNU software. We do not want GNU programs to +have idiosyncratic configuration options. + + Packages that perform part of the compilation process may support +cross-compilation. In such a case, the host and target machines for the +program may be different. + + The `configure' script should normally treat the specified type of +system as both the host and the target, thus producing a program which +works for the same type of machine that it runs on. + + To compile a program to run on a host type that differs from the +build type, use the configure option `--host=HOSTTYPE', where HOSTTYPE +uses the same syntax as BUILDTYPE. The host type normally defaults to +the build type. + + To configure a cross-compiler, cross-assembler, or what have you, you +should specify a target different from the host, using the configure +option `--target=TARGETTYPE'. The syntax for TARGETTYPE is the same as +for the host type. So the command would look like this: + + ./configure --host=HOSTTYPE --target=TARGETTYPE + + The target type normally defaults to the host type. Programs for +which cross-operation is not meaningful need not accept the `--target' +option, because configuring an entire operating system for +cross-operation is not a meaningful operation. + + Some programs have ways of configuring themselves automatically. If +your program is set up to do this, your `configure' script can simply +ignore most of its arguments. + + +File: standards.info, Node: Makefile Conventions, Next: Releases, Prev: Configuration, Up: Managing Releases + +7.2 Makefile Conventions +======================== + +This node describes conventions for writing the Makefiles for GNU +programs. Using Automake will help you write a Makefile that follows +these conventions. + +* Menu: + +* Makefile Basics:: General conventions for Makefiles. +* Utilities in Makefiles:: Utilities to be used in Makefiles. +* Command Variables:: Variables for specifying commands. +* DESTDIR:: Supporting staged installs. +* Directory Variables:: Variables for installation directories. +* Standard Targets:: Standard targets for users. +* Install Command Categories:: Three categories of commands in the `install' + rule: normal, pre-install and post-install. + + +File: standards.info, Node: Makefile Basics, Next: Utilities in Makefiles, Up: Makefile Conventions + +7.2.1 General Conventions for Makefiles +--------------------------------------- + +Every Makefile should contain this line: + + SHELL = /bin/sh + +to avoid trouble on systems where the `SHELL' variable might be +inherited from the environment. (This is never a problem with GNU +`make'.) + + Different `make' programs have incompatible suffix lists and +implicit rules, and this sometimes creates confusion or misbehavior. So +it is a good idea to set the suffix list explicitly using only the +suffixes you need in the particular Makefile, like this: + + .SUFFIXES: + .SUFFIXES: .c .o + +The first line clears out the suffix list, the second introduces all +suffixes which may be subject to implicit rules in this Makefile. + + Don't assume that `.' is in the path for command execution. When +you need to run programs that are a part of your package during the +make, please make sure that it uses `./' if the program is built as +part of the make or `$(srcdir)/' if the file is an unchanging part of +the source code. Without one of these prefixes, the current search +path is used. + + The distinction between `./' (the "build directory") and +`$(srcdir)/' (the "source directory") is important because users can +build in a separate directory using the `--srcdir' option to +`configure'. A rule of the form: + + foo.1 : foo.man sedscript + sed -e sedscript foo.man > foo.1 + +will fail when the build directory is not the source directory, because +`foo.man' and `sedscript' are in the source directory. + + When using GNU `make', relying on `VPATH' to find the source file +will work in the case where there is a single dependency file, since +the `make' automatic variable `$<' will represent the source file +wherever it is. (Many versions of `make' set `$<' only in implicit +rules.) A Makefile target like + + foo.o : bar.c + $(CC) -I. -I$(srcdir) $(CFLAGS) -c bar.c -o foo.o + +should instead be written as + + foo.o : bar.c + $(CC) -I. -I$(srcdir) $(CFLAGS) -c $< -o $@ + +in order to allow `VPATH' to work correctly. When the target has +multiple dependencies, using an explicit `$(srcdir)' is the easiest way +to make the rule work well. For example, the target above for `foo.1' +is best written as: + + foo.1 : foo.man sedscript + sed -e $(srcdir)/sedscript $(srcdir)/foo.man > $@ + + GNU distributions usually contain some files which are not source +files--for example, Info files, and the output from Autoconf, Automake, +Bison or Flex. Since these files normally appear in the source +directory, they should always appear in the source directory, not in the +build directory. So Makefile rules to update them should put the +updated files in the source directory. + + However, if a file does not appear in the distribution, then the +Makefile should not put it in the source directory, because building a +program in ordinary circumstances should not modify the source directory +in any way. + + Try to make the build and installation targets, at least (and all +their subtargets) work correctly with a parallel `make'. + + +File: standards.info, Node: Utilities in Makefiles, Next: Command Variables, Prev: Makefile Basics, Up: Makefile Conventions + +7.2.2 Utilities in Makefiles +---------------------------- + +Write the Makefile commands (and any shell scripts, such as +`configure') to run in `sh', not in `csh'. Don't use any special +features of `ksh' or `bash'. + + The `configure' script and the Makefile rules for building and +installation should not use any utilities directly except these: + + cat cmp cp diff echo egrep expr false grep install-info + ln ls mkdir mv pwd rm rmdir sed sleep sort tar test touch true + + The compression program `gzip' can be used in the `dist' rule. + + Stick to the generally supported options for these programs. For +example, don't use `mkdir -p', convenient as it may be, because most +systems don't support it. + + It is a good idea to avoid creating symbolic links in makefiles, +since a few systems don't support them. + + The Makefile rules for building and installation can also use +compilers and related programs, but should do so via `make' variables +so that the user can substitute alternatives. Here are some of the +programs we mean: + + ar bison cc flex install ld ldconfig lex + make makeinfo ranlib texi2dvi yacc + + Use the following `make' variables to run those programs: + + $(AR) $(BISON) $(CC) $(FLEX) $(INSTALL) $(LD) $(LDCONFIG) $(LEX) + $(MAKE) $(MAKEINFO) $(RANLIB) $(TEXI2DVI) $(YACC) + + When you use `ranlib' or `ldconfig', you should make sure nothing +bad happens if the system does not have the program in question. +Arrange to ignore an error from that command, and print a message before +the command to tell the user that failure of this command does not mean +a problem. (The Autoconf `AC_PROG_RANLIB' macro can help with this.) + + If you use symbolic links, you should implement a fallback for +systems that don't have symbolic links. + + Additional utilities that can be used via Make variables are: + + chgrp chmod chown mknod + + It is ok to use other utilities in Makefile portions (or scripts) +intended only for particular systems where you know those utilities +exist. + + +File: standards.info, Node: Command Variables, Next: DESTDIR, Prev: Utilities in Makefiles, Up: Makefile Conventions + +7.2.3 Variables for Specifying Commands +--------------------------------------- + +Makefiles should provide variables for overriding certain commands, +options, and so on. + + In particular, you should run most utility programs via variables. +Thus, if you use Bison, have a variable named `BISON' whose default +value is set with `BISON = bison', and refer to it with `$(BISON)' +whenever you need to use Bison. + + File management utilities such as `ln', `rm', `mv', and so on, need +not be referred to through variables in this way, since users don't +need to replace them with other programs. + + Each program-name variable should come with an options variable that +is used to supply options to the program. Append `FLAGS' to the +program-name variable name to get the options variable name--for +example, `BISONFLAGS'. (The names `CFLAGS' for the C compiler, +`YFLAGS' for yacc, and `LFLAGS' for lex, are exceptions to this rule, +but we keep them because they are standard.) Use `CPPFLAGS' in any +compilation command that runs the preprocessor, and use `LDFLAGS' in +any compilation command that does linking as well as in any direct use +of `ld'. + + If there are C compiler options that _must_ be used for proper +compilation of certain files, do not include them in `CFLAGS'. Users +expect to be able to specify `CFLAGS' freely themselves. Instead, +arrange to pass the necessary options to the C compiler independently +of `CFLAGS', by writing them explicitly in the compilation commands or +by defining an implicit rule, like this: + + CFLAGS = -g + ALL_CFLAGS = -I. $(CFLAGS) + .c.o: + $(CC) -c $(CPPFLAGS) $(ALL_CFLAGS) $< + + Do include the `-g' option in `CFLAGS', because that is not +_required_ for proper compilation. You can consider it a default that +is only recommended. If the package is set up so that it is compiled +with GCC by default, then you might as well include `-O' in the default +value of `CFLAGS' as well. + + Put `CFLAGS' last in the compilation command, after other variables +containing compiler options, so the user can use `CFLAGS' to override +the others. + + `CFLAGS' should be used in every invocation of the C compiler, both +those which do compilation and those which do linking. + + Every Makefile should define the variable `INSTALL', which is the +basic command for installing a file into the system. + + Every Makefile should also define the variables `INSTALL_PROGRAM' +and `INSTALL_DATA'. (The default for `INSTALL_PROGRAM' should be +`$(INSTALL)'; the default for `INSTALL_DATA' should be `${INSTALL} -m +644'.) Then it should use those variables as the commands for actual +installation, for executables and non-executables respectively. +Minimal use of these variables is as follows: + + $(INSTALL_PROGRAM) foo $(bindir)/foo + $(INSTALL_DATA) libfoo.a $(libdir)/libfoo.a + + However, it is preferable to support a `DESTDIR' prefix on the +target files, as explained in the next section. + +Always use a file name, not a directory name, as the second argument of +the installation commands. Use a separate command for each file to be +installed. + + +File: standards.info, Node: DESTDIR, Next: Directory Variables, Prev: Command Variables, Up: Makefile Conventions + +7.2.4 `DESTDIR': support for staged installs +-------------------------------------------- + +`DESTDIR' is a variable prepended to each installed target file, like +this: + + $(INSTALL_PROGRAM) foo $(DESTDIR)$(bindir)/foo + $(INSTALL_DATA) libfoo.a $(DESTDIR)$(libdir)/libfoo.a + + The `DESTDIR' variable is specified by the user on the `make' +command line. For example: + + make DESTDIR=/tmp/stage install + +`DESTDIR' should be supported only in the `install*' and `uninstall*' +targets, as those are the only targets where it is useful. + + If your installation step would normally install +`/usr/local/bin/foo' and `/usr/local/lib/libfoo.a', then an +installation invoked as in the example above would install +`/tmp/stage/usr/local/bin/foo' and `/tmp/stage/usr/local/lib/libfoo.a' +instead. + + Prepending the variable `DESTDIR' to each target in this way +provides for "staged installs", where the installed files are not +placed directly into their expected location but are instead copied +into a temporary location (`DESTDIR'). However, installed files +maintain their relative directory structure and any embedded file names +will not be modified. + + You should not set the value of `DESTDIR' in your `Makefile' at all; +then the files are installed into their expected locations by default. +Also, specifying `DESTDIR' should not change the operation of the +software in any way, so its value should not be included in any file +contents. + + `DESTDIR' support is commonly used in package creation. It is also +helpful to users who want to understand what a given package will +install where, and to allow users who don't normally have permissions +to install into protected areas to build and install before gaining +those permissions. Finally, it can be useful with tools such as +`stow', where code is installed in one place but made to appear to be +installed somewhere else using symbolic links or special mount +operations. So, we strongly recommend GNU packages support `DESTDIR', +though it is not an absolute requirement. + + +File: standards.info, Node: Directory Variables, Next: Standard Targets, Prev: DESTDIR, Up: Makefile Conventions + +7.2.5 Variables for Installation Directories +-------------------------------------------- + +Installation directories should always be named by variables, so it is +easy to install in a nonstandard place. The standard names for these +variables and the values they should have in GNU packages are described +below. They are based on a standard file system layout; variants of it +are used in GNU/Linux and other modern operating systems. + + Installers are expected to override these values when calling `make' +(e.g., `make prefix=/usr install' or `configure' (e.g., `configure +--prefix=/usr'). GNU packages should not try to guess which value +should be appropriate for these variables on the system they are being +installed onto: use the default settings specified here so that all GNU +packages behave identically, allowing the installer to achieve any +desired layout. + + These first two variables set the root for the installation. All the +other installation directories should be subdirectories of one of these +two, and nothing should be directly installed into these two +directories. + +`prefix' + A prefix used in constructing the default values of the variables + listed below. The default value of `prefix' should be + `/usr/local'. When building the complete GNU system, the prefix + will be empty and `/usr' will be a symbolic link to `/'. (If you + are using Autoconf, write it as `@prefix@'.) + + Running `make install' with a different value of `prefix' from the + one used to build the program should _not_ recompile the program. + +`exec_prefix' + A prefix used in constructing the default values of some of the + variables listed below. The default value of `exec_prefix' should + be `$(prefix)'. (If you are using Autoconf, write it as + `@exec_prefix@'.) + + Generally, `$(exec_prefix)' is used for directories that contain + machine-specific files (such as executables and subroutine + libraries), while `$(prefix)' is used directly for other + directories. + + Running `make install' with a different value of `exec_prefix' + from the one used to build the program should _not_ recompile the + program. + + Executable programs are installed in one of the following +directories. + +`bindir' + The directory for installing executable programs that users can + run. This should normally be `/usr/local/bin', but write it as + `$(exec_prefix)/bin'. (If you are using Autoconf, write it as + `@bindir@'.) + +`sbindir' + The directory for installing executable programs that can be run + from the shell, but are only generally useful to system + administrators. This should normally be `/usr/local/sbin', but + write it as `$(exec_prefix)/sbin'. (If you are using Autoconf, + write it as `@sbindir@'.) + +`libexecdir' + The directory for installing executable programs to be run by other + programs rather than by users. This directory should normally be + `/usr/local/libexec', but write it as `$(exec_prefix)/libexec'. + (If you are using Autoconf, write it as `@libexecdir@'.) + + The definition of `libexecdir' is the same for all packages, so + you should install your data in a subdirectory thereof. Most + packages install their data under `$(libexecdir)/PACKAGE-NAME/', + possibly within additional subdirectories thereof, such as + `$(libexecdir)/PACKAGE-NAME/MACHINE/VERSION'. + + Data files used by the program during its execution are divided into +categories in two ways. + + * Some files are normally modified by programs; others are never + normally modified (though users may edit some of these). + + * Some files are architecture-independent and can be shared by all + machines at a site; some are architecture-dependent and can be + shared only by machines of the same kind and operating system; + others may never be shared between two machines. + + This makes for six different possibilities. However, we want to +discourage the use of architecture-dependent files, aside from object +files and libraries. It is much cleaner to make other data files +architecture-independent, and it is generally not hard. + + Here are the variables Makefiles should use to specify directories +to put these various kinds of files in: + +`datarootdir' + The root of the directory tree for read-only + architecture-independent data files. This should normally be + `/usr/local/share', but write it as `$(prefix)/share'. (If you + are using Autoconf, write it as `@datarootdir@'.) `datadir''s + default value is based on this variable; so are `infodir', + `mandir', and others. + +`datadir' + The directory for installing idiosyncratic read-only + architecture-independent data files for this program. This is + usually the same place as `datarootdir', but we use the two + separate variables so that you can move these program-specific + files without altering the location for Info files, man pages, etc. + + This should normally be `/usr/local/share', but write it as + `$(datarootdir)'. (If you are using Autoconf, write it as + `@datadir@'.) + + The definition of `datadir' is the same for all packages, so you + should install your data in a subdirectory thereof. Most packages + install their data under `$(datadir)/PACKAGE-NAME/'. + +`sysconfdir' + The directory for installing read-only data files that pertain to a + single machine-that is to say, files for configuring a host. + Mailer and network configuration files, `/etc/passwd', and so + forth belong here. All the files in this directory should be + ordinary ASCII text files. This directory should normally be + `/usr/local/etc', but write it as `$(prefix)/etc'. (If you are + using Autoconf, write it as `@sysconfdir@'.) + + Do not install executables here in this directory (they probably + belong in `$(libexecdir)' or `$(sbindir)'). Also do not install + files that are modified in the normal course of their use (programs + whose purpose is to change the configuration of the system + excluded). Those probably belong in `$(localstatedir)'. + +`sharedstatedir' + The directory for installing architecture-independent data files + which the programs modify while they run. This should normally be + `/usr/local/com', but write it as `$(prefix)/com'. (If you are + using Autoconf, write it as `@sharedstatedir@'.) + +`localstatedir' + The directory for installing data files which the programs modify + while they run, and that pertain to one specific machine. Users + should never need to modify files in this directory to configure + the package's operation; put such configuration information in + separate files that go in `$(datadir)' or `$(sysconfdir)'. + `$(localstatedir)' should normally be `/usr/local/var', but write + it as `$(prefix)/var'. (If you are using Autoconf, write it as + `@localstatedir@'.) + + These variables specify the directory for installing certain specific +types of files, if your program has them. Every GNU package should +have Info files, so every program needs `infodir', but not all need +`libdir' or `lispdir'. + +`includedir' + The directory for installing header files to be included by user + programs with the C `#include' preprocessor directive. This + should normally be `/usr/local/include', but write it as + `$(prefix)/include'. (If you are using Autoconf, write it as + `@includedir@'.) + + Most compilers other than GCC do not look for header files in + directory `/usr/local/include'. So installing the header files + this way is only useful with GCC. Sometimes this is not a problem + because some libraries are only really intended to work with GCC. + But some libraries are intended to work with other compilers. + They should install their header files in two places, one + specified by `includedir' and one specified by `oldincludedir'. + +`oldincludedir' + The directory for installing `#include' header files for use with + compilers other than GCC. This should normally be `/usr/include'. + (If you are using Autoconf, you can write it as `@oldincludedir@'.) + + The Makefile commands should check whether the value of + `oldincludedir' is empty. If it is, they should not try to use + it; they should cancel the second installation of the header files. + + A package should not replace an existing header in this directory + unless the header came from the same package. Thus, if your Foo + package provides a header file `foo.h', then it should install the + header file in the `oldincludedir' directory if either (1) there + is no `foo.h' there or (2) the `foo.h' that exists came from the + Foo package. + + To tell whether `foo.h' came from the Foo package, put a magic + string in the file--part of a comment--and `grep' for that string. + +`docdir' + The directory for installing documentation files (other than Info) + for this package. By default, it should be + `/usr/local/share/doc/YOURPKG', but it should be written as + `$(datarootdir)/doc/YOURPKG'. (If you are using Autoconf, write + it as `@docdir@'.) The YOURPKG subdirectory, which may include a + version number, prevents collisions among files with common names, + such as `README'. + +`infodir' + The directory for installing the Info files for this package. By + default, it should be `/usr/local/share/info', but it should be + written as `$(datarootdir)/info'. (If you are using Autoconf, + write it as `@infodir@'.) `infodir' is separate from `docdir' for + compatibility with existing practice. + +`htmldir' +`dvidir' +`pdfdir' +`psdir' + Directories for installing documentation files in the particular + format. They should all be set to `$(docdir)' by default. (If + you are using Autoconf, write them as `@htmldir@', `@dvidir@', + etc.) Packages which supply several translations of their + documentation should install them in `$(htmldir)/'LL, + `$(pdfdir)/'LL, etc. where LL is a locale abbreviation such as + `en' or `pt_BR'. + +`libdir' + The directory for object files and libraries of object code. Do + not install executables here, they probably ought to go in + `$(libexecdir)' instead. The value of `libdir' should normally be + `/usr/local/lib', but write it as `$(exec_prefix)/lib'. (If you + are using Autoconf, write it as `@libdir@'.) + +`lispdir' + The directory for installing any Emacs Lisp files in this package. + By default, it should be `/usr/local/share/emacs/site-lisp', but + it should be written as `$(datarootdir)/emacs/site-lisp'. + + If you are using Autoconf, write the default as `@lispdir@'. In + order to make `@lispdir@' work, you need the following lines in + your `configure.in' file: + + lispdir='${datarootdir}/emacs/site-lisp' + AC_SUBST(lispdir) + +`localedir' + The directory for installing locale-specific message catalogs for + this package. By default, it should be `/usr/local/share/locale', + but it should be written as `$(datarootdir)/locale'. (If you are + using Autoconf, write it as `@localedir@'.) This directory + usually has a subdirectory per locale. + + Unix-style man pages are installed in one of the following: + +`mandir' + The top-level directory for installing the man pages (if any) for + this package. It will normally be `/usr/local/share/man', but you + should write it as `$(datarootdir)/man'. (If you are using + Autoconf, write it as `@mandir@'.) + +`man1dir' + The directory for installing section 1 man pages. Write it as + `$(mandir)/man1'. + +`man2dir' + The directory for installing section 2 man pages. Write it as + `$(mandir)/man2' + +`...' + *Don't make the primary documentation for any GNU software be a + man page. Write a manual in Texinfo instead. Man pages are just + for the sake of people running GNU software on Unix, which is a + secondary application only.* + +`manext' + The file name extension for the installed man page. This should + contain a period followed by the appropriate digit; it should + normally be `.1'. + +`man1ext' + The file name extension for installed section 1 man pages. + +`man2ext' + The file name extension for installed section 2 man pages. + +`...' + Use these names instead of `manext' if the package needs to + install man pages in more than one section of the manual. + + And finally, you should set the following variable: + +`srcdir' + The directory for the sources being compiled. The value of this + variable is normally inserted by the `configure' shell script. + (If you are using Autoconf, use `srcdir = @srcdir@'.) + + For example: + + # Common prefix for installation directories. + # NOTE: This directory must exist when you start the install. + prefix = /usr/local + datarootdir = $(prefix)/share + datadir = $(datarootdir) + exec_prefix = $(prefix) + # Where to put the executable for the command `gcc'. + bindir = $(exec_prefix)/bin + # Where to put the directories used by the compiler. + libexecdir = $(exec_prefix)/libexec + # Where to put the Info files. + infodir = $(datarootdir)/info + + If your program installs a large number of files into one of the +standard user-specified directories, it might be useful to group them +into a subdirectory particular to that program. If you do this, you +should write the `install' rule to create these subdirectories. + + Do not expect the user to include the subdirectory name in the value +of any of the variables listed above. The idea of having a uniform set +of variable names for installation directories is to enable the user to +specify the exact same values for several different GNU packages. In +order for this to be useful, all the packages must be designed so that +they will work sensibly when the user does so. + + At times, not all of these variables may be implemented in the +current release of Autoconf and/or Automake; but as of Autoconf 2.60, we +believe all of them are. When any are missing, the descriptions here +serve as specifications for what Autoconf will implement. As a +programmer, you can either use a development version of Autoconf or +avoid using these variables until a stable release is made which +supports them. + + +File: standards.info, Node: Standard Targets, Next: Install Command Categories, Prev: Directory Variables, Up: Makefile Conventions + +7.2.6 Standard Targets for Users +-------------------------------- + +All GNU programs should have the following targets in their Makefiles: + +`all' + Compile the entire program. This should be the default target. + This target need not rebuild any documentation files; Info files + should normally be included in the distribution, and DVI (and other + documentation format) files should be made only when explicitly + asked for. + + By default, the Make rules should compile and link with `-g', so + that executable programs have debugging symbols. Users who don't + mind being helpless can strip the executables later if they wish. + +`install' + Compile the program and copy the executables, libraries, and so on + to the file names where they should reside for actual use. If + there is a simple test to verify that a program is properly + installed, this target should run that test. + + Do not strip executables when installing them. Devil-may-care + users can use the `install-strip' target to do that. + + If possible, write the `install' target rule so that it does not + modify anything in the directory where the program was built, + provided `make all' has just been done. This is convenient for + building the program under one user name and installing it under + another. + + The commands should create all the directories in which files are + to be installed, if they don't already exist. This includes the + directories specified as the values of the variables `prefix' and + `exec_prefix', as well as all subdirectories that are needed. One + way to do this is by means of an `installdirs' target as described + below. + + Use `-' before any command for installing a man page, so that + `make' will ignore any errors. This is in case there are systems + that don't have the Unix man page documentation system installed. + + The way to install Info files is to copy them into `$(infodir)' + with `$(INSTALL_DATA)' (*note Command Variables::), and then run + the `install-info' program if it is present. `install-info' is a + program that edits the Info `dir' file to add or update the menu + entry for the given Info file; it is part of the Texinfo package. + Here is a sample rule to install an Info file: + + $(DESTDIR)$(infodir)/foo.info: foo.info + $(POST_INSTALL) + # There may be a newer info file in . than in srcdir. + -if test -f foo.info; then d=.; \ + else d=$(srcdir); fi; \ + $(INSTALL_DATA) $$d/foo.info $(DESTDIR)$@; \ + # Run install-info only if it exists. + # Use `if' instead of just prepending `-' to the + # line so we notice real errors from install-info. + # We use `$(SHELL) -c' because some shells do not + # fail gracefully when there is an unknown command. + if $(SHELL) -c 'install-info --version' \ + >/dev/null 2>&1; then \ + install-info --dir-file=$(DESTDIR)$(infodir)/dir \ + $(DESTDIR)$(infodir)/foo.info; \ + else true; fi + + When writing the `install' target, you must classify all the + commands into three categories: normal ones, "pre-installation" + commands and "post-installation" commands. *Note Install Command + Categories::. + +`install-html' +`install-dvi' +`install-pdf' +`install-ps' + These targets install documentation in formats other than Info; + they're intended to be called explicitly by the person installing + the package, if that format is desired. GNU prefers Info files, + so these must be installed by the `install' target. + + When you have many documentation files to install, we recommend + that you avoid collisions and clutter by arranging for these + targets to install in subdirectories of the appropriate + installation directory, such as `htmldir'. As one example, if + your package has multiple manuals, and you wish to install HTML + documentation with many files (such as the "split" mode output by + `makeinfo --html'), you'll certainly want to use subdirectories, + or two nodes with the same name in different manuals will + overwrite each other. + + Please make these `install-FORMAT' targets invoke the commands for + the FORMAT target, for example, by making FORMAT a dependency. + +`uninstall' + Delete all the installed files--the copies that the `install' and + `install-*' targets create. + + This rule should not modify the directories where compilation is + done, only the directories where files are installed. + + The uninstallation commands are divided into three categories, + just like the installation commands. *Note Install Command + Categories::. + +`install-strip' + Like `install', but strip the executable files while installing + them. In simple cases, this target can use the `install' target in + a simple way: + + install-strip: + $(MAKE) INSTALL_PROGRAM='$(INSTALL_PROGRAM) -s' \ + install + + But if the package installs scripts as well as real executables, + the `install-strip' target can't just refer to the `install' + target; it has to strip the executables but not the scripts. + + `install-strip' should not strip the executables in the build + directory which are being copied for installation. It should only + strip the copies that are installed. + + Normally we do not recommend stripping an executable unless you + are sure the program has no bugs. However, it can be reasonable + to install a stripped executable for actual execution while saving + the unstripped executable elsewhere in case there is a bug. + +`clean' + Delete all files in the current directory that are normally + created by building the program. Also delete files in other + directories if they are created by this makefile. However, don't + delete the files that record the configuration. Also preserve + files that could be made by building, but normally aren't because + the distribution comes with them. There is no need to delete + parent directories that were created with `mkdir -p', since they + could have existed anyway. + + Delete `.dvi' files here if they are not part of the distribution. + +`distclean' + Delete all files in the current directory (or created by this + makefile) that are created by configuring or building the program. + If you have unpacked the source and built the program without + creating any other files, `make distclean' should leave only the + files that were in the distribution. However, there is no need to + delete parent directories that were created with `mkdir -p', since + they could have existed anyway. + +`mostlyclean' + Like `clean', but may refrain from deleting a few files that people + normally don't want to recompile. For example, the `mostlyclean' + target for GCC does not delete `libgcc.a', because recompiling it + is rarely necessary and takes a lot of time. + +`maintainer-clean' + Delete almost everything that can be reconstructed with this + Makefile. This typically includes everything deleted by + `distclean', plus more: C source files produced by Bison, tags + tables, Info files, and so on. + + The reason we say "almost everything" is that running the command + `make maintainer-clean' should not delete `configure' even if + `configure' can be remade using a rule in the Makefile. More + generally, `make maintainer-clean' should not delete anything that + needs to exist in order to run `configure' and then begin to build + the program. Also, there is no need to delete parent directories + that were created with `mkdir -p', since they could have existed + anyway. These are the only exceptions; `maintainer-clean' should + delete everything else that can be rebuilt. + + The `maintainer-clean' target is intended to be used by a + maintainer of the package, not by ordinary users. You may need + special tools to reconstruct some of the files that `make + maintainer-clean' deletes. Since these files are normally + included in the distribution, we don't take care to make them easy + to reconstruct. If you find you need to unpack the full + distribution again, don't blame us. + + To help make users aware of this, the commands for the special + `maintainer-clean' target should start with these two: + + @echo 'This command is intended for maintainers to use; it' + @echo 'deletes files that may need special tools to rebuild.' + +`TAGS' + Update a tags table for this program. + +`info' + Generate any Info files needed. The best way to write the rules + is as follows: + + info: foo.info + + foo.info: foo.texi chap1.texi chap2.texi + $(MAKEINFO) $(srcdir)/foo.texi + + You must define the variable `MAKEINFO' in the Makefile. It should + run the `makeinfo' program, which is part of the Texinfo + distribution. + + Normally a GNU distribution comes with Info files, and that means + the Info files are present in the source directory. Therefore, + the Make rule for an info file should update it in the source + directory. When users build the package, ordinarily Make will not + update the Info files because they will already be up to date. + +`dvi' +`html' +`pdf' +`ps' + Generate documentation files in the given format. These targets + should always exist, but any or all can be a no-op if the given + output format cannot be generated. These targets should not be + dependencies of the `all' target; the user must manually invoke + them. + + Here's an example rule for generating DVI files from Texinfo: + + dvi: foo.dvi + + foo.dvi: foo.texi chap1.texi chap2.texi + $(TEXI2DVI) $(srcdir)/foo.texi + + You must define the variable `TEXI2DVI' in the Makefile. It should + run the program `texi2dvi', which is part of the Texinfo + distribution.(1) Alternatively, write just the dependencies, and + allow GNU `make' to provide the command. + + Here's another example, this one for generating HTML from Texinfo: + + html: foo.html + + foo.html: foo.texi chap1.texi chap2.texi + $(TEXI2HTML) $(srcdir)/foo.texi + + Again, you would define the variable `TEXI2HTML' in the Makefile; + for example, it might run `makeinfo --no-split --html' (`makeinfo' + is part of the Texinfo distribution). + +`dist' + Create a distribution tar file for this program. The tar file + should be set up so that the file names in the tar file start with + a subdirectory name which is the name of the package it is a + distribution for. This name can include the version number. + + For example, the distribution tar file of GCC version 1.40 unpacks + into a subdirectory named `gcc-1.40'. + + The easiest way to do this is to create a subdirectory + appropriately named, use `ln' or `cp' to install the proper files + in it, and then `tar' that subdirectory. + + Compress the tar file with `gzip'. For example, the actual + distribution file for GCC version 1.40 is called `gcc-1.40.tar.gz'. + + The `dist' target should explicitly depend on all non-source files + that are in the distribution, to make sure they are up to date in + the distribution. *Note Making Releases: Releases. + +`check' + Perform self-tests (if any). The user must build the program + before running the tests, but need not install the program; you + should write the self-tests so that they work when the program is + built but not installed. + + The following targets are suggested as conventional names, for +programs in which they are useful. + +`installcheck' + Perform installation tests (if any). The user must build and + install the program before running the tests. You should not + assume that `$(bindir)' is in the search path. + +`installdirs' + It's useful to add a target named `installdirs' to create the + directories where files are installed, and their parent + directories. There is a script called `mkinstalldirs' which is + convenient for this; you can find it in the Texinfo package. You + can use a rule like this: + + # Make sure all installation directories (e.g. $(bindir)) + # actually exist by making them if necessary. + installdirs: mkinstalldirs + $(srcdir)/mkinstalldirs $(bindir) $(datadir) \ + $(libdir) $(infodir) \ + $(mandir) + + or, if you wish to support `DESTDIR', + + # Make sure all installation directories (e.g. $(bindir)) + # actually exist by making them if necessary. + installdirs: mkinstalldirs + $(srcdir)/mkinstalldirs \ + $(DESTDIR)$(bindir) $(DESTDIR)$(datadir) \ + $(DESTDIR)$(libdir) $(DESTDIR)$(infodir) \ + $(DESTDIR)$(mandir) + + This rule should not modify the directories where compilation is + done. It should do nothing but create installation directories. + + ---------- Footnotes ---------- + + (1) `texi2dvi' uses TeX to do the real work of formatting. TeX is +not distributed with Texinfo. + + +File: standards.info, Node: Install Command Categories, Prev: Standard Targets, Up: Makefile Conventions + +7.2.7 Install Command Categories +-------------------------------- + +When writing the `install' target, you must classify all the commands +into three categories: normal ones, "pre-installation" commands and +"post-installation" commands. + + Normal commands move files into their proper places, and set their +modes. They may not alter any files except the ones that come entirely +from the package they belong to. + + Pre-installation and post-installation commands may alter other +files; in particular, they can edit global configuration files or data +bases. + + Pre-installation commands are typically executed before the normal +commands, and post-installation commands are typically run after the +normal commands. + + The most common use for a post-installation command is to run +`install-info'. This cannot be done with a normal command, since it +alters a file (the Info directory) which does not come entirely and +solely from the package being installed. It is a post-installation +command because it needs to be done after the normal command which +installs the package's Info files. + + Most programs don't need any pre-installation commands, but we have +the feature just in case it is needed. + + To classify the commands in the `install' rule into these three +categories, insert "category lines" among them. A category line +specifies the category for the commands that follow. + + A category line consists of a tab and a reference to a special Make +variable, plus an optional comment at the end. There are three +variables you can use, one for each category; the variable name +specifies the category. Category lines are no-ops in ordinary execution +because these three Make variables are normally undefined (and you +_should not_ define them in the makefile). + + Here are the three possible category lines, each with a comment that +explains what it means: + + $(PRE_INSTALL) # Pre-install commands follow. + $(POST_INSTALL) # Post-install commands follow. + $(NORMAL_INSTALL) # Normal commands follow. + + If you don't use a category line at the beginning of the `install' +rule, all the commands are classified as normal until the first category +line. If you don't use any category lines, all the commands are +classified as normal. + + These are the category lines for `uninstall': + + $(PRE_UNINSTALL) # Pre-uninstall commands follow. + $(POST_UNINSTALL) # Post-uninstall commands follow. + $(NORMAL_UNINSTALL) # Normal commands follow. + + Typically, a pre-uninstall command would be used for deleting entries +from the Info directory. + + If the `install' or `uninstall' target has any dependencies which +act as subroutines of installation, then you should start _each_ +dependency's commands with a category line, and start the main target's +commands with a category line also. This way, you can ensure that each +command is placed in the right category regardless of which of the +dependencies actually run. + + Pre-installation and post-installation commands should not run any +programs except for these: + + [ basename bash cat chgrp chmod chown cmp cp dd diff echo + egrep expand expr false fgrep find getopt grep gunzip gzip + hostname install install-info kill ldconfig ln ls md5sum + mkdir mkfifo mknod mv printenv pwd rm rmdir sed sort tee + test touch true uname xargs yes + + The reason for distinguishing the commands in this way is for the +sake of making binary packages. Typically a binary package contains +all the executables and other files that need to be installed, and has +its own method of installing them--so it does not need to run the normal +installation commands. But installing the binary package does need to +execute the pre-installation and post-installation commands. + + Programs to build binary packages work by extracting the +pre-installation and post-installation commands. Here is one way of +extracting the pre-installation commands (the `-s' option to `make' is +needed to silence messages about entering subdirectories): + + make -s -n install -o all \ + PRE_INSTALL=pre-install \ + POST_INSTALL=post-install \ + NORMAL_INSTALL=normal-install \ + | gawk -f pre-install.awk + +where the file `pre-install.awk' could contain this: + + $0 ~ /^(normal-install|post-install)[ \t]*$/ {on = 0} + on {print $0} + $0 ~ /^pre-install[ \t]*$/ {on = 1} + + +File: standards.info, Node: Releases, Prev: Makefile Conventions, Up: Managing Releases + +7.3 Making Releases +=================== + +You should identify each release with a pair of version numbers, a +major version and a minor. We have no objection to using more than two +numbers, but it is very unlikely that you really need them. + + Package the distribution of `Foo version 69.96' up in a gzipped tar +file with the name `foo-69.96.tar.gz'. It should unpack into a +subdirectory named `foo-69.96'. + + Building and installing the program should never modify any of the +files contained in the distribution. This means that all the files +that form part of the program in any way must be classified into "source +files" and "non-source files". Source files are written by humans and +never changed automatically; non-source files are produced from source +files by programs under the control of the Makefile. + + The distribution should contain a file named `README' which gives +the name of the package, and a general description of what it does. It +is also good to explain the purpose of each of the first-level +subdirectories in the package, if there are any. The `README' file +should either state the version number of the package, or refer to where +in the package it can be found. + + The `README' file should refer to the file `INSTALL', which should +contain an explanation of the installation procedure. + + The `README' file should also refer to the file which contains the +copying conditions. The GNU GPL, if used, should be in a file called +`COPYING'. If the GNU LGPL is used, it should be in a file called +`COPYING.LIB'. + + Naturally, all the source files must be in the distribution. It is +okay to include non-source files in the distribution, provided they are +up-to-date and machine-independent, so that building the distribution +normally will never modify them. We commonly include non-source files +produced by Bison, `lex', TeX, and `makeinfo'; this helps avoid +unnecessary dependencies between our distributions, so that users can +install whichever packages they want to install. + + Non-source files that might actually be modified by building and +installing the program should *never* be included in the distribution. +So if you do distribute non-source files, always make sure they are up +to date when you make a new distribution. + + Make sure that the directory into which the distribution unpacks (as +well as any subdirectories) are all world-writable (octal mode 777). +This is so that old versions of `tar' which preserve the ownership and +permissions of the files from the tar archive will be able to extract +all the files even if the user is unprivileged. + + Make sure that all the files in the distribution are world-readable. + + Don't include any symbolic links in the distribution itself. If the +tar file contains symbolic links, then people cannot even unpack it on +systems that don't support symbolic links. Also, don't use multiple +names for one file in different directories, because certain file +systems cannot handle this and that prevents unpacking the distribution. + + Try to make sure that all the file names will be unique on MS-DOS. A +name on MS-DOS consists of up to 8 characters, optionally followed by a +period and up to three characters. MS-DOS will truncate extra +characters both before and after the period. Thus, `foobarhacker.c' +and `foobarhacker.o' are not ambiguous; they are truncated to +`foobarha.c' and `foobarha.o', which are distinct. + + Include in your distribution a copy of the `texinfo.tex' you used to +test print any `*.texinfo' or `*.texi' files. + + Likewise, if your program uses small GNU software packages like +regex, getopt, obstack, or termcap, include them in the distribution +file. Leaving them out would make the distribution file a little +smaller at the expense of possible inconvenience to a user who doesn't +know what other files to get. + + +File: standards.info, Node: References, Next: GNU Free Documentation License, Prev: Managing Releases, Up: Top + +8 References to Non-Free Software and Documentation +*************************************************** + +A GNU program should not recommend use of any non-free program. We +can't stop some people from writing proprietary programs, or stop other +people from using them, but we can and should refuse to advertise them +to new potential customers. Proprietary software is a social and +ethical problem, and the point of GNU is to solve that problem. + + The GNU definition of free software is found on the GNU web site at +`http://www.gnu.org/philosophy/free-sw.html', and the definition of +free documentation is found at +`http://www.gnu.org/philosophy/free-doc.html'. A list of important +licenses and whether they qualify as free is in +`http://www.gnu.org/licenses/license-list.html'. The terms "free" and +"non-free", used in this document, refer to that definition. If it is +not clear whether a license qualifies as free under this definition, +please ask the GNU Project by writing to <licensing@gnu.org>. We will +answer, and if the license is an important one, we will add it to the +list. + + When a non-free program or system is well known, you can mention it +in passing--that is harmless, since users who might want to use it +probably already know about it. For instance, it is fine to explain +how to build your package on top of some widely used non-free operating +system, or how to use it together with some widely used non-free +program. + + However, you should give only the necessary information to help those +who already use the non-free program to use your program with it--don't +give, or refer to, any further information about the proprietary +program, and don't imply that the proprietary program enhances your +program, or that its existence is in any way a good thing. The goal +should be that people already using the proprietary program will get +the advice they need about how to use your free program with it, while +people who don't already use the proprietary program will not see +anything to lead them to take an interest in it. + + If a non-free program or system is obscure in your program's domain, +your program should not mention or support it at all, since doing so +would tend to popularize the non-free program more than it popularizes +your program. (You cannot hope to find many additional users among the +users of Foobar if the users of Foobar are few.) + + Sometimes a program is free software in itself but depends on a +non-free platform in order to run. For instance, many Java programs +depend on the parts of Sun's Java implementation which are not yet free +software, and won't run on the GNU Java Compiler (which does not yet +have all the features) or won't run with the GNU Java libraries. We +hope this particular problem will be gone in a few months, when Sun +makes the standard Java libraries free software, but of course the +general principle remains: you should not recommend programs that +depend on non-free software to run. + + Some free programs encourage the use of non-free software. A typical +example is `mplayer'. It is free software in itself, and the free code +can handle some kinds of files. However, `mplayer' recommends use of +non-free codecs for other kinds of files, and users that install +`mplayer' are very likely to install those codecs along with it. To +recommend `mplayer' is, in effect, to recommend the non-free codecs. +We must not do that, so we cannot recommend `mplayer' either. + + In general, you should also not recommend programs that themselves +strongly recommend the use of non-free software. + + A GNU package should not refer the user to any non-free documentation +for free software. Free documentation that can be included in free +operating systems is essential for completing the GNU system, or any +free operating system, so it is a major focus of the GNU Project; to +recommend use of documentation that we are not allowed to use in GNU +would weaken the impetus for the community to produce documentation +that we can include. So GNU packages should never recommend non-free +documentation. + + By contrast, it is ok to refer to journal articles and textbooks in +the comments of a program for explanation of how it functions, even +though they be non-free. This is because we don't include such things +in the GNU system even if we are allowed to--they are outside the scope +of an operating system project. + + Referring to a web site that describes or recommends a non-free +program is in effect promoting that software, so please do not make +links (or mention by name) web sites that contain such material. This +policy is relevant particularly for the web pages for a GNU package. + + Following links from nearly any web site can lead to non-free +software; this is an inescapable aspect of the nature of the web, and +in itself is no objection to linking to a site. As long as the site +does not itself recommend a non-free program, there is no need be +concerned about the sites it links to for other reasons. + + Thus, for example, you should not make a link to AT&T's web site, +because that recommends AT&T's non-free software packages; you should +not make a link to a site that links to AT&T's site saying it is a +place to get a non-free program; but if a site you want to link to +refers to AT&T's web site in some other context (such as long-distance +telephone service), that is not a problem. + + +File: standards.info, Node: GNU Free Documentation License, Next: Index, Prev: References, Up: Top + +Appendix A GNU Free Documentation License +***************************************** + + Version 1.2, November 2002 + + Copyright (C) 2000,2001,2002 Free Software Foundation, Inc. + 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA + + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + 0. PREAMBLE + + The purpose of this License is to make a manual, textbook, or other + functional and useful document "free" in the sense of freedom: to + assure everyone the effective freedom to copy and redistribute it, + with or without modifying it, either commercially or + noncommercially. Secondarily, this License preserves for the + author and publisher a way to get credit for their work, while not + being considered responsible for modifications made by others. + + This License is a kind of "copyleft", which means that derivative + works of the document must themselves be free in the same sense. + It complements the GNU General Public License, which is a copyleft + license designed for free software. + + We have designed this License in order to use it for manuals for + free software, because free software needs free documentation: a + free program should come with manuals providing the same freedoms + that the software does. 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Preserve the network location, if any, given in the Document + for public access to a Transparent copy of the Document, and + likewise the network locations given in the Document for + previous versions it was based on. These may be placed in + the "History" section. You may omit a network location for a + work that was published at least four years before the + Document itself, or if the original publisher of the version + it refers to gives permission. + + K. For any section Entitled "Acknowledgements" or "Dedications", + Preserve the Title of the section, and preserve in the + section all the substance and tone of each of the contributor + acknowledgements and/or dedications given therein. + + L. Preserve all the Invariant Sections of the Document, + unaltered in their text and in their titles. Section numbers + or the equivalent are not considered part of the section + titles. + + M. Delete any section Entitled "Endorsements". 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COMBINING DOCUMENTS + + You may combine the Document with other documents released under + this License, under the terms defined in section 4 above for + modified versions, provided that you include in the combination + all of the Invariant Sections of all of the original documents, + unmodified, and list them all as Invariant Sections of your + combined work in its license notice, and that you preserve all + their Warranty Disclaimers. + + The combined work need only contain one copy of this License, and + multiple identical Invariant Sections may be replaced with a single + copy. If there are multiple Invariant Sections with the same name + but different contents, make the title of each such section unique + by adding at the end of it, in parentheses, the name of the + original author or publisher of that section if known, or else a + unique number. Make the same adjustment to the section titles in + the list of Invariant Sections in the license notice of the + combined work. + + In the combination, you must combine any sections Entitled + "History" in the various original documents, forming one section + Entitled "History"; likewise combine any sections Entitled + "Acknowledgements", and any sections Entitled "Dedications". You + must delete all sections Entitled "Endorsements." + + 6. COLLECTIONS OF DOCUMENTS + + You may make a collection consisting of the Document and other + documents released under this License, and replace the individual + copies of this License in the various documents with a single copy + that is included in the collection, provided that you follow the + rules of this License for verbatim copying of each of the + documents in all other respects. + + You may extract a single document from such a collection, and + distribute it individually under this License, provided you insert + a copy of this License into the extracted document, and follow + this License in all other respects regarding verbatim copying of + that document. + + 7. AGGREGATION WITH INDEPENDENT WORKS + + A compilation of the Document or its derivatives with other + separate and independent documents or works, in or on a volume of + a storage or distribution medium, is called an "aggregate" if the + copyright resulting from the compilation is not used to limit the + legal rights of the compilation's users beyond what the individual + works permit. When the Document is included in an aggregate, this + License does not apply to the other works in the aggregate which + are not themselves derivative works of the Document. + + If the Cover Text requirement of section 3 is applicable to these + copies of the Document, then if the Document is less than one half + of the entire aggregate, the Document's Cover Texts may be placed + on covers that bracket the Document within the aggregate, or the + electronic equivalent of covers if the Document is in electronic + form. Otherwise they must appear on printed covers that bracket + the whole aggregate. + + 8. TRANSLATION + + Translation is considered a kind of modification, so you may + distribute translations of the Document under the terms of section + 4. Replacing Invariant Sections with translations requires special + permission from their copyright holders, but you may include + translations of some or all Invariant Sections in addition to the + original versions of these Invariant Sections. You may include a + translation of this License, and all the license notices in the + Document, and any Warranty Disclaimers, provided that you also + include the original English version of this License and the + original versions of those notices and disclaimers. In case of a + disagreement between the translation and the original version of + this License or a notice or disclaimer, the original version will + prevail. + + If a section in the Document is Entitled "Acknowledgements", + "Dedications", or "History", the requirement (section 4) to + Preserve its Title (section 1) will typically require changing the + actual title. + + 9. TERMINATION + + You may not copy, modify, sublicense, or distribute the Document + except as expressly provided for under this License. Any other + attempt to copy, modify, sublicense or distribute the Document is + void, and will automatically terminate your rights under this + License. However, parties who have received copies, or rights, + from you under this License will not have their licenses + terminated so long as such parties remain in full compliance. + + 10. FUTURE REVISIONS OF THIS LICENSE + + The Free Software Foundation may publish new, revised versions of + the GNU Free Documentation License from time to time. Such new + versions will be similar in spirit to the present version, but may + differ in detail to address new problems or concerns. See + `http://www.gnu.org/copyleft/'. + + Each version of the License is given a distinguishing version + number. If the Document specifies that a particular numbered + version of this License "or any later version" applies to it, you + have the option of following the terms and conditions either of + that specified version or of any later version that has been + published (not as a draft) by the Free Software Foundation. If + the Document does not specify a version number of this License, + you may choose any version ever published (not as a draft) by the + Free Software Foundation. + +ADDENDUM: How to use this License for your documents +==================================================== + +To use this License in a document you have written, include a copy of +the License in the document and put the following copyright and license +notices just after the title page: + + Copyright (C) YEAR YOUR NAME. + Permission is granted to copy, distribute and/or modify this document + under the terms of the GNU Free Documentation License, Version 1.2 + or any later version published by the Free Software Foundation; + with no Invariant Sections, no Front-Cover Texts, and no Back-Cover + Texts. A copy of the license is included in the section entitled ``GNU + Free Documentation License''. + + If you have Invariant Sections, Front-Cover Texts and Back-Cover +Texts, replace the "with...Texts." line with this: + + with the Invariant Sections being LIST THEIR TITLES, with + the Front-Cover Texts being LIST, and with the Back-Cover Texts + being LIST. + + If you have Invariant Sections without Cover Texts, or some other +combination of the three, merge those two alternatives to suit the +situation. + + If your document contains nontrivial examples of program code, we +recommend releasing these examples in parallel under your choice of +free software license, such as the GNU General Public License, to +permit their use in free software. + + +File: standards.info, Node: Index, Prev: GNU Free Documentation License, Up: Top + +Index +***** + + +* Menu: + +* #endif, commenting: Comments. (line 60) +* --help output: --help. (line 6) +* --version output: --version. (line 6) +* -Wall compiler option: Syntactic Conventions. + (line 10) +* accepting contributions: Contributions. (line 6) +* address for bug reports: --help. (line 11) +* ANSI C standard: Standard C. (line 6) +* arbitrary limits on data: Semantics. (line 6) +* ASCII characters: Character Set. (line 6) +* autoconf: System Portability. (line 23) +* avoiding proprietary code: Reading Non-Free Code. + (line 6) +* behavior, dependent on program's name: User Interfaces. (line 6) +* binary packages: Install Command Categories. + (line 80) +* bindir: Directory Variables. (line 54) +* braces, in C source: Formatting. (line 6) +* bug reports: --help. (line 11) +* canonical name of a program: --version. (line 12) +* casting pointers to integers: CPU Portability. (line 90) +* CGI programs, standard options for: Command-Line Interfaces. + (line 31) +* change logs: Change Logs. (line 6) +* change logs, conditional changes: Conditional Changes. (line 6) +* change logs, style: Style of Change Logs. + (line 6) +* character set: Character Set. (line 6) +* command-line arguments, decoding: Semantics. (line 46) +* command-line interface: Command-Line Interfaces. + (line 6) +* commenting: Comments. (line 6) +* compatibility with C and POSIX standards: Compatibility. (line 6) +* compiler warnings: Syntactic Conventions. + (line 10) +* conditional changes, and change logs: Conditional Changes. (line 6) +* conditionals, comments for: Comments. (line 60) +* configure: Configuration. (line 6) +* control-L: Formatting. (line 118) +* conventions for makefiles: Makefile Conventions. + (line 6) +* corba: Graphical Interfaces. + (line 16) +* credits for manuals: Manual Credits. (line 6) +* data types, and portability: CPU Portability. (line 6) +* declaration for system functions: System Functions. (line 21) +* DESTDIR: DESTDIR. (line 6) +* documentation: Documentation. (line 6) +* doschk: Names. (line 38) +* downloading this manual: Preface. (line 17) +* encodings: Character Set. (line 6) +* error messages: Semantics. (line 19) +* error messages, formatting: Errors. (line 6) +* exec_prefix: Directory Variables. (line 36) +* expressions, splitting: Formatting. (line 81) +* FDL, GNU Free Documentation License: GNU Free Documentation License. + (line 6) +* file usage: File Usage. (line 6) +* file-name limitations: Names. (line 38) +* formatting error messages: Errors. (line 6) +* formatting source code: Formatting. (line 6) +* formfeed: Formatting. (line 118) +* function argument, declaring: Syntactic Conventions. + (line 6) +* function prototypes: Standard C. (line 17) +* getopt: Command-Line Interfaces. + (line 6) +* gettext: Internationalization. + (line 6) +* gnome: Graphical Interfaces. + (line 16) +* graphical user interface: Graphical Interfaces. + (line 6) +* grave accent: Quote Characters. (line 6) +* gtk+: Graphical Interfaces. + (line 6) +* GUILE: Source Language. (line 38) +* implicit int: Syntactic Conventions. + (line 6) +* impossible conditions: Semantics. (line 70) +* installations, staged: DESTDIR. (line 6) +* internationalization: Internationalization. + (line 6) +* left quote: Quote Characters. (line 6) +* legal aspects: Legal Issues. (line 6) +* legal papers: Contributions. (line 6) +* libexecdir: Directory Variables. (line 67) +* libraries: Libraries. (line 6) +* library functions, and portability: System Functions. (line 6) +* license for manuals: License for Manuals. (line 6) +* lint: Syntactic Conventions. + (line 109) +* locale-specific quote characters: Quote Characters. (line 6) +* long option names: Option Table. (line 6) +* long-named options: Command-Line Interfaces. + (line 12) +* makefile, conventions for: Makefile Conventions. + (line 6) +* malloc return value: Semantics. (line 25) +* man pages: Man Pages. (line 6) +* manual structure: Manual Structure Details. + (line 6) +* memory allocation failure: Semantics. (line 25) +* memory usage: Memory Usage. (line 6) +* message text, and internationalization: Internationalization. + (line 29) +* mmap: Mmap. (line 6) +* multiple variables in a line: Syntactic Conventions. + (line 35) +* names of variables, functions, and files: Names. (line 6) +* NEWS file: NEWS File. (line 6) +* non-ASCII characters: Character Set. (line 6) +* non-POSIX systems, and portability: System Portability. (line 32) +* non-standard extensions: Using Extensions. (line 6) +* NUL characters: Semantics. (line 11) +* open brace: Formatting. (line 6) +* optional features, configure-time: Configuration. (line 83) +* options for compatibility: Compatibility. (line 14) +* options, standard command-line: Command-Line Interfaces. + (line 31) +* output device and program's behavior: User Interfaces. (line 13) +* packaging: Releases. (line 6) +* PATH_INFO, specifying standard options as: Command-Line Interfaces. + (line 31) +* portability, and data types: CPU Portability. (line 6) +* portability, and library functions: System Functions. (line 6) +* portability, between system types: System Portability. (line 6) +* POSIX compatibility: Compatibility. (line 6) +* POSIXLY_CORRECT, environment variable: Compatibility. (line 21) +* post-installation commands: Install Command Categories. + (line 6) +* pre-installation commands: Install Command Categories. + (line 6) +* prefix: Directory Variables. (line 26) +* program configuration: Configuration. (line 6) +* program design: Design Advice. (line 6) +* program name and its behavior: User Interfaces. (line 6) +* program's canonical name: --version. (line 12) +* programming languages: Source Language. (line 6) +* proprietary programs: Reading Non-Free Code. + (line 6) +* quote characters: Quote Characters. (line 6) +* README file: Releases. (line 21) +* references to non-free material: References. (line 6) +* releasing: Managing Releases. (line 6) +* sbindir: Directory Variables. (line 60) +* signal handling: Semantics. (line 59) +* spaces before open-paren: Formatting. (line 75) +* staged installs: DESTDIR. (line 6) +* standard command-line options: Command-Line Interfaces. + (line 31) +* standards for makefiles: Makefile Conventions. + (line 6) +* string library functions: System Functions. (line 55) +* syntactic conventions: Syntactic Conventions. + (line 6) +* table of long options: Option Table. (line 6) +* temporary files: Semantics. (line 84) +* temporary variables: Syntactic Conventions. + (line 23) +* texinfo.tex, in a distribution: Releases. (line 70) +* TMPDIR environment variable: Semantics. (line 84) +* trademarks: Trademarks. (line 6) +* where to obtain standards.texi: Preface. (line 17) + + + +Tag Table: +Node: Top797 +Node: Preface2053 +Node: Legal Issues4168 +Node: Reading Non-Free Code4638 +Node: Contributions6368 +Node: Trademarks8606 +Node: Design Advice10241 +Node: Source Language10833 +Node: Compatibility12845 +Node: Using Extensions14473 +Node: Standard C16049 +Node: Conditional Compilation18452 +Node: Program Behavior19850 +Node: Non-GNU Standards20906 +Node: Semantics23187 +Node: Libraries27906 +Node: Errors29151 +Node: User Interfaces31644 +Node: Graphical Interfaces33249 +Node: Command-Line Interfaces34285 +Node: --version36317 +Node: --help42210 +Node: Option Table42764 +Node: Memory Usage57705 +Node: File Usage58736 +Node: Writing C59486 +Node: Formatting60458 +Node: Comments64747 +Node: Syntactic Conventions68299 +Node: Names71761 +Node: System Portability73973 +Node: CPU Portability76863 +Node: System Functions80775 +Node: Internationalization85972 +Node: Character Set89966 +Node: Quote Characters90779 +Node: Mmap92299 +Node: Documentation93007 +Node: GNU Manuals94113 +Node: Doc Strings and Manuals99851 +Node: Manual Structure Details101404 +Node: License for Manuals102822 +Node: Manual Credits103796 +Node: Printed Manuals104189 +Node: NEWS File104875 +Node: Change Logs105553 +Node: Change Log Concepts106307 +Node: Style of Change Logs108396 +Node: Simple Changes110896 +Node: Conditional Changes112338 +Node: Indicating the Part Changed113760 +Node: Man Pages114287 +Node: Reading other Manuals116599 +Node: Managing Releases117390 +Node: Configuration118171 +Node: Makefile Conventions125891 +Node: Makefile Basics126773 +Node: Utilities in Makefiles129947 +Node: Command Variables132092 +Node: DESTDIR135314 +Node: Directory Variables137463 +Node: Standard Targets151956 +Ref: Standard Targets-Footnote-1165471 +Node: Install Command Categories165571 +Node: Releases170104 +Node: References174031 +Node: GNU Free Documentation License179526 +Node: Index201958 + +End Tag Table |