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[SelectionDAG] Clean up SCALAR_TO_VECTOR handling in SimplifyDemanded… #157027

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Merged
merged 1 commit into from
Sep 5, 2025
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[SelectionDAG] Clean up SCALAR_TO_VECTOR handling in SimplifyDemanded… #157027

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21 changes: 0 additions & 21 deletions llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -3227,27 +3227,6 @@ bool TargetLowering::SimplifyDemandedVectorElts(
KnownUndef.setAllBits();
return TLO.CombineTo(Op, TLO.DAG.getUNDEF(VT));
}
SDValue ScalarSrc = Op.getOperand(0);
if (ScalarSrc.getOpcode() == ISD::EXTRACT_VECTOR_ELT) {
SDValue Src = ScalarSrc.getOperand(0);
SDValue Idx = ScalarSrc.getOperand(1);
EVT SrcVT = Src.getValueType();

ElementCount SrcEltCnt = SrcVT.getVectorElementCount();

if (SrcEltCnt.isScalable())
return false;

unsigned NumSrcElts = SrcEltCnt.getFixedValue();
if (isNullConstant(Idx)) {
APInt SrcDemandedElts = APInt::getOneBitSet(NumSrcElts, 0);
APInt SrcUndef = KnownUndef.zextOrTrunc(NumSrcElts);
APInt SrcZero = KnownZero.zextOrTrunc(NumSrcElts);
if (SimplifyDemandedVectorElts(Src, SrcDemandedElts, SrcUndef, SrcZero,
TLO, Depth + 1))
return true;
}
}
KnownUndef.setHighBits(NumElts - 1);
break;
}
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