diff options
Diffstat (limited to 'doc/getting/index.rst')
-rw-r--r-- | doc/getting/index.rst | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/doc/getting/index.rst b/doc/getting/index.rst new file mode 100644 index 000000000..f64e44caf --- /dev/null +++ b/doc/getting/index.rst @@ -0,0 +1,79 @@ +.. _BUILD: + +Building GHDL from Sources +########################## + +.. rubric :: Download + +GHDL can be downloaded as a `zip-file <https://github.com/ghdl/ghdl/archive/master.zip>`_/`tar-file <https://github.com/ghdl/ghdl/archive/master.tar.gz>`_ +(latest 'master' branch) or cloned with ``git clone`` from GitHub. GitHub +offers HTTPS and SSH as transfer protocols. See the :ref:`RELEASE:Sources` +page for further details. + +.. IMPORTANT :: + Since GHDL is written in `Ada`, independently of the code generator you use, + the a compiler is required. Most GNU/Linux package managers provide a package + named ``gcc-ada`` or ``gcc-gnat``. Alternatively, `GNU Ada compiler`, `GNAT GPL`, + can be downloaded anonymously from `libre.adacore.com <http://libre.adacore.com/tools/gnat-gpl-edition/>`_ (2014, or later; for x86, 32 or 64 bits). + Then, untar and run the doinstall script. + +.. rubric :: Available back-ends + +GHDL currently supports three different back-ends (code generators): + +* mcode - built-in x86 (or x86_64) code generator +* GCC - Gnu Compiler Collection (`gcc.gnu.org <http://gcc.gnu.org/>`_) +* LLVM - Low-Level Virtual Machine (`llvm.org <http://llvm.org/>`_) + +Here is a short comparison, so that you can choose the one you want to use: + ++----------------------------+----------------------------------------------------------------------------+---------------------------------------------------------+ +| Back-end | Pros | Cons | ++============================+============================================================================+=========================================================+ +| :ref:`mcode <BUILD:mcode>` | * Very easy to build | * Simulation is slower | +| | * Very quick analysis | * x86_64/i386 only | +| | * Can handle very large designs | | ++----------------------------+----------------------------------------------------------------------------+---------------------------------------------------------+ +| :ref:`LLVM <BUILD:llvm>` | * Generated code is faster | * Build is more complex than mcode | +| | * Generated code can be debugged (with ``-g``) | | +| | * Easier to build than GCC | | +| | * Ported to many platforms (x86, x86_64, armv7/aarch64) | | ++----------------------------+----------------------------------------------------------------------------+---------------------------------------------------------+ +| :ref:`GCC <BUILD:gcc>` | * Generated code is faster (particularly with ``-O`` or ``-O2``) | * Build is even more complex | +| | * Generated code can be debugged (with ``-g``) | * Analysis can take time (particularly for large units) | +| | * Ported to many platforms (x86, x86_64, PowerPC, SPARC) | * Code coverage collection (``gcov``) is unique to GCC | ++----------------------------+----------------------------------------------------------------------------+---------------------------------------------------------+ + +.. toctree:: + :hidden: + + Directories + mcode + LLVM + GCC + +.. HINT :: + The output of both GCC and LLVM is an executable file, but `mcode` does not + generate any. Therefore, if using GCC/LLVM, the call with argument ``-r`` can + be replaced with direct execution of the binary. See section :ref:`USING:QuickStart`. + +After making your choice, you can jump to the corresponding section. +However, we suggest you to read :ref:`BUILD:dir_structure` first, so that you +know where the content will be placed and which files are expected to be +created. + +.. HINT :: + In these instructions, the configure script is executed in the source directory; but you can execute in a different + directory too, like this: + + .. CODE:: Bash + + $ mkdir ghdl-objs + $ cd ghdl-objs + $ ../path/to/ghdl/configure ... + +.. HINT :: On Windows, building GHDL with mcode backend and GNAT GPL 32 bit seems to be the only way to get a standalone native executable. + + * MINGW/MSYS2 builds depend on the environment/runtime. + * For 64 bit, no native compiler exists from AdaCore. + * That Ada to .NET compiler, which might work for 32 or 64 bit. is not up-to-date. |