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[Hexagon] Explicitly truncate constant in UAddSubO #127360

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Merged
merged 1 commit into from
Feb 17, 2025
Merged

[Hexagon] Explicitly truncate constant in UAddSubO #127360

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2 changes: 1 addition & 1 deletion llvm/lib/Target/Hexagon/HexagonISelLowering.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -3273,7 +3273,7 @@ HexagonTargetLowering::LowerUAddSubO(SDValue Op, SelectionDAG &DAG) const {
if (Opc == ISD::USUBO) {
SDValue Op = DAG.getNode(ISD::SUB, dl, VTs.VTs[0], {X, Y});
SDValue Ov = DAG.getSetCC(dl, MVT::i1, Op,
DAG.getConstant(-1, dl, ty(Op)), ISD::SETEQ);
DAG.getAllOnesConstant(dl, ty(Op)), ISD::SETEQ);
return DAG.getMergeValues({Op, Ov}, dl);
}
}
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18 changes: 18 additions & 0 deletions llvm/test/CodeGen/Hexagon/iss127296.ll
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@@ -0,0 +1,18 @@
; RUN: llc -mtriple=hexagon -O0 < %s | FileCheck %s

; CHECK: r0 = add(r0,#-1)

define fastcc void @os.linux.tls.initStatic(i32 %x) {
%1 = call { i32, i1 } @llvm.usub.with.overflow.i32(i32 %x, i32 1)
br label %2

2: ; preds = %0
%3 = extractvalue { i32, i1 } %1, 0
ret void
}

; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)
declare { i32, i1 } @llvm.usub.with.overflow.i32(i32, i32) #0

attributes #0 = { nocallback nofree nosync nounwind speculatable willreturn memory(none) }