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[AArch64] Use DAG.getNegative instead of getNegatedInteger (NFC) #157342

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Merged
merged 1 commit into from
Sep 7, 2025
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[AArch64] Use DAG.getNegative instead of getNegatedInteger (NFC) #157342

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16 changes: 5 additions & 11 deletions llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -20899,13 +20899,6 @@ static bool isNegatedInteger(SDValue Op) {
return Op.getOpcode() == ISD::SUB && isNullConstant(Op.getOperand(0));
}

static SDValue getNegatedInteger(SDValue Op, SelectionDAG &DAG) {
SDLoc DL(Op);
EVT VT = Op.getValueType();
SDValue Zero = DAG.getConstant(0, DL, VT);
return DAG.getNode(ISD::SUB, DL, VT, Zero, Op);
}

// Try to fold
//
// (neg (csel X, Y)) -> (csel (neg X), (neg Y))
Expand All @@ -20924,16 +20917,17 @@ static SDValue performNegCSelCombine(SDNode *N, SelectionDAG &DAG) {
SDValue N0 = CSel.getOperand(0);
SDValue N1 = CSel.getOperand(1);

// If both of them is not negations, it's not worth the folding as it
// If neither of them are negations, it's not worth the folding as it
// introduces two additional negations while reducing one negation.
if (!isNegatedInteger(N0) && !isNegatedInteger(N1))
return SDValue();

SDValue N0N = getNegatedInteger(N0, DAG);
SDValue N1N = getNegatedInteger(N1, DAG);

SDLoc DL(N);
EVT VT = CSel.getValueType();

SDValue N0N = DAG.getNegative(N0, DL, VT);
SDValue N1N = DAG.getNegative(N1, DL, VT);

return DAG.getNode(AArch64ISD::CSEL, DL, VT, N0N, N1N, CSel.getOperand(2),
CSel.getOperand(3));
}
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