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[RISCV] Use getNegative instead of subtracting from zero. NFC #162313

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Merged
merged 2 commits into from
Oct 8, 2025
Merged

[RISCV] Use getNegative instead of subtracting from zero. NFC #162313

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[RISCV] Use getNegative instead of subtracting from zero. NFC
svs-quic Oct 7, 2025
51cf7bc
Merge branch 'main' into getNegative
svs-quic Oct 8, 2025
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5 changes: 2 additions & 3 deletions llvm/lib/Target/RISCV/RISCVISelLowering.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -15721,8 +15721,7 @@ static SDValue combineAddOfBooleanXor(SDNode *N, SelectionDAG &DAG) {
return SDValue();

// Emit a negate of the setcc.
return DAG.getNode(ISD::SUB, DL, VT, DAG.getConstant(0, DL, VT),
N0.getOperand(0));
return DAG.getNegative(N0.getOperand(0), DL, VT);
}

static SDValue performADDCombine(SDNode *N,
Expand Down Expand Up @@ -16974,7 +16973,7 @@ performSIGN_EXTEND_INREGCombine(SDNode *N, TargetLowering::DAGCombinerInfo &DCI,

// Fold (sext_inreg (setcc), i1) -> (sub 0, (setcc))
if (Opc == ISD::SETCC && SrcVT == MVT::i1 && DCI.isAfterLegalizeDAG())
return DAG.getNode(ISD::SUB, DL, VT, DAG.getConstant(0, DL, VT), Src);
return DAG.getNegative(Src, DL, VT);

// Fold (sext_inreg (xor (setcc), -1), i1) -> (add (setcc), -1)
if (Opc == ISD::XOR && SrcVT == MVT::i1 &&
Expand Down