diff options
Diffstat (limited to 'kernel/calc.cc')
| -rw-r--r-- | kernel/calc.cc | 79 |
1 files changed, 48 insertions, 31 deletions
diff --git a/kernel/calc.cc b/kernel/calc.cc index a56db93aa..41179d045 100644 --- a/kernel/calc.cc +++ b/kernel/calc.cc @@ -21,21 +21,10 @@ // Schneier, Bruce (1996). Applied Cryptography: Protocols, Algorithms, and Source Code in C, // Second Edition (2nd ed.). Wiley. ISBN 978-0-471-11709-4, page 244 -#include "kernel/log.h" -#include "kernel/rtlil.h" +#include "kernel/yosys.h" #include "libs/bigint/BigIntegerLibrary.hh" -#include <assert.h> -static void extend(RTLIL::Const &arg, int width, bool is_signed) -{ - RTLIL::State padding = RTLIL::State::S0; - - if (arg.bits.size() > 0 && (is_signed || arg.bits.back() > RTLIL::State::S1)) - padding = arg.bits.back(); - - while (int(arg.bits.size()) < width) - arg.bits.push_back(padding); -} +YOSYS_NAMESPACE_BEGIN static void extend_u0(RTLIL::Const &arg, int width, bool is_signed) { @@ -46,6 +35,8 @@ static void extend_u0(RTLIL::Const &arg, int width, bool is_signed) while (int(arg.bits.size()) < width) arg.bits.push_back(padding); + + arg.bits.resize(width); } static BigInteger const2big(const RTLIL::Const &val, bool as_signed, int &undef_bit_pos) @@ -277,7 +268,7 @@ RTLIL::Const RTLIL::const_logic_or(const RTLIL::Const &arg1, const RTLIL::Const return result; } -static RTLIL::Const const_shift(const RTLIL::Const &arg1, const RTLIL::Const &arg2, bool sign_ext, int direction, int result_len) +static RTLIL::Const const_shift_worker(const RTLIL::Const &arg1, const RTLIL::Const &arg2, bool sign_ext, int direction, int result_len) { int undef_bit_pos = -1; BigInteger offset = const2big(arg2, false, undef_bit_pos) * direction; @@ -305,29 +296,62 @@ static RTLIL::Const const_shift(const RTLIL::Const &arg1, const RTLIL::Const &ar RTLIL::Const RTLIL::const_shl(const RTLIL::Const &arg1, const RTLIL::Const &arg2, bool signed1, bool, int result_len) { RTLIL::Const arg1_ext = arg1; - extend(arg1_ext, result_len, signed1); - return const_shift(arg1_ext, arg2, false, -1, result_len); + extend_u0(arg1_ext, result_len, signed1); + return const_shift_worker(arg1_ext, arg2, false, -1, result_len); } RTLIL::Const RTLIL::const_shr(const RTLIL::Const &arg1, const RTLIL::Const &arg2, bool signed1, bool, int result_len) { RTLIL::Const arg1_ext = arg1; - extend(arg1_ext, result_len, signed1); - return const_shift(arg1_ext, arg2, false, +1, result_len); + extend_u0(arg1_ext, std::max(result_len, SIZE(arg1)), signed1); + return const_shift_worker(arg1_ext, arg2, false, +1, result_len); } RTLIL::Const RTLIL::const_sshl(const RTLIL::Const &arg1, const RTLIL::Const &arg2, bool signed1, bool signed2, int result_len) { if (!signed1) return const_shl(arg1, arg2, signed1, signed2, result_len); - return const_shift(arg1, arg2, true, -1, result_len); + return const_shift_worker(arg1, arg2, true, -1, result_len); } RTLIL::Const RTLIL::const_sshr(const RTLIL::Const &arg1, const RTLIL::Const &arg2, bool signed1, bool signed2, int result_len) { if (!signed1) return const_shr(arg1, arg2, signed1, signed2, result_len); - return const_shift(arg1, arg2, true, +1, result_len); + return const_shift_worker(arg1, arg2, true, +1, result_len); +} + +static RTLIL::Const const_shift_shiftx(const RTLIL::Const &arg1, const RTLIL::Const &arg2, bool, bool signed2, int result_len, RTLIL::State other_bits) +{ + int undef_bit_pos = -1; + BigInteger offset = const2big(arg2, signed2, undef_bit_pos); + + if (result_len < 0) + result_len = arg1.bits.size(); + + RTLIL::Const result(RTLIL::State::Sx, result_len); + if (undef_bit_pos >= 0) + return result; + + for (int i = 0; i < result_len; i++) { + BigInteger pos = BigInteger(i) + offset; + if (pos < 0 || pos >= arg1.bits.size()) + result.bits[i] = other_bits; + else + result.bits[i] = arg1.bits[pos.toInt()]; + } + + return result; +} + +RTLIL::Const RTLIL::const_shift(const RTLIL::Const &arg1, const RTLIL::Const &arg2, bool signed1, bool signed2, int result_len) +{ + return const_shift_shiftx(arg1, arg2, signed1, signed2, result_len, RTLIL::State::S0); +} + +RTLIL::Const RTLIL::const_shiftx(const RTLIL::Const &arg1, const RTLIL::Const &arg2, bool signed1, bool signed2, int result_len) +{ + return const_shift_shiftx(arg1, arg2, signed1, signed2, result_len, RTLIL::State::Sx); } RTLIL::Const RTLIL::const_lt(const RTLIL::Const &arg1, const RTLIL::Const &arg2, bool signed1, bool signed2, int result_len) @@ -538,14 +562,6 @@ RTLIL::Const RTLIL::const_pow(const RTLIL::Const &arg1, const RTLIL::Const &arg2 RTLIL::Const RTLIL::const_pos(const RTLIL::Const &arg1, const RTLIL::Const&, bool signed1, bool, int result_len) { RTLIL::Const arg1_ext = arg1; - extend(arg1_ext, result_len, signed1); - - return arg1_ext; -} - -RTLIL::Const RTLIL::const_bu0(const RTLIL::Const &arg1, const RTLIL::Const&, bool signed1, bool, int result_len) -{ - RTLIL::Const arg1_ext = arg1; extend_u0(arg1_ext, result_len, signed1); return arg1_ext; @@ -554,9 +570,10 @@ RTLIL::Const RTLIL::const_bu0(const RTLIL::Const &arg1, const RTLIL::Const&, boo RTLIL::Const RTLIL::const_neg(const RTLIL::Const &arg1, const RTLIL::Const&, bool signed1, bool, int result_len) { RTLIL::Const arg1_ext = arg1; - extend(arg1_ext, result_len, signed1); - RTLIL::Const zero(RTLIL::State::S0, 1); - return RTLIL::const_sub(zero, arg1_ext, false, signed1, result_len); + + return RTLIL::const_sub(zero, arg1_ext, true, signed1, result_len); } +YOSYS_NAMESPACE_END + |