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Added $shift and $shiftx cell types (needed for correct part select behavior)

This commit is contained in:
Clifford Wolf 2014-07-29 14:42:33 +02:00
parent 48822e79a3
commit 397b00252d
12 changed files with 214 additions and 40 deletions

View file

@ -276,7 +276,7 @@ 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;
@ -305,28 +305,61 @@ RTLIL::Const RTLIL::const_shl(const RTLIL::Const &arg1, const RTLIL::Const &arg2
{
RTLIL::Const arg1_ext = arg1;
extend_u0(arg1_ext, result_len, signed1);
return const_shift(arg1_ext, arg2, false, -1, result_len);
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_u0(arg1_ext, result_len, signed1);
return const_shift(arg1_ext, arg2, false, +1, result_len);
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)