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Copy with 1'bx padding in $shiftx

This commit is contained in:
Eddie Hung 2019-04-28 13:04:34 -07:00
parent ea0e0722bb
commit acafcdc94d
1 changed files with 11 additions and 1 deletions
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12
passes/techmap/shregmap.cc
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@ -178,7 +178,17 @@ struct ShregmapTechXilinx7 : ShregmapTech
// Only map if $shiftx exclusively covers the shift register
if (shiftx->type == "$shiftx") {
if (GetSize(taps) != shiftx->getParam("\\A_WIDTH").as_int())
if (GetSize(taps) > shiftx->getParam("\\A_WIDTH").as_int())
return false;
// Due to padding the most significant bits of A may be 1'bx,
// and if so, discount them
if (GetSize(taps) < shiftx->getParam("\\A_WIDTH").as_int()) {
const SigSpec A = shiftx->getPort("\\A");
const int A_width = shiftx->getParam("\\A_WIDTH").as_int();
for (int i = GetSize(taps); i < A_width; ++i)
if (A[i] != RTLIL::Sx) return false;
}
else if (GetSize(taps) != shiftx->getParam("\\A_WIDTH").as_int())
return false;
}
else if (shiftx->type == "$mux") {