[llvm] d7e129d - [SelectionDAGBuilder] Only check VPCmp for NaNs in fp comparisons (#189749)

[via llvm-commits]

Author: zGoldthorpe
Date: 2026-04-01T17:00:55Z
New Revision: d7e129dffbe1d8cdafd6731a4ff130da68deb40b

URL: https://github.com/llvm/llvm-project/commit/d7e129dffbe1d8cdafd6731a4ff130da68deb40b
DIFF: https://github.com/llvm/llvm-project/commit/d7e129dffbe1d8cdafd6731a4ff130da68deb40b.diff

LOG: [SelectionDAGBuilder] Only check VPCmp for NaNs in fp comparisons (#189749)

`getFCmpCodeWithoutNaN` should only be used for FP comparisons (which is
also the only context in which `isKnownNeverNaN` makes sense).

Added: 
    

Modified: 
    llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp

Removed: 
    


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diff  --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 69ba9721401e1..cd4470d5f20fe 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -8859,11 +8859,9 @@ void SelectionDAGBuilder::visitVPCmp(const VPCmpIntrinsic &VPIntrin) {
 
   ISD::CondCode Condition;
   CmpInst::Predicate CondCode = VPIntrin.getPredicate();
-  bool IsFP = VPIntrin.getOperand(0)->getType()->isFPOrFPVectorTy();
-  Condition = IsFP ? getFCmpCondCode(CondCode) : getICmpCondCode(CondCode);
 
-  SDValue Op1 = getValue(VPIntrin.getOperand(0));
-  SDValue Op2 = getValue(VPIntrin.getOperand(1));
+  Value *Op1 = VPIntrin.getOperand(0);
+  Value *Op2 = VPIntrin.getOperand(1);
   // #2 is the condition code
   SDValue MaskOp = getValue(VPIntrin.getOperand(3));
   SDValue EVL = getValue(VPIntrin.getOperand(4));
@@ -8872,12 +8870,19 @@ void SelectionDAGBuilder::visitVPCmp(const VPCmpIntrinsic &VPIntrin) {
          "Unexpected target EVL type");
   EVL = DAG.getNode(ISD::ZERO_EXTEND, DL, EVLParamVT, EVL);
 
+  if (VPIntrin.getOperand(0)->getType()->isFPOrFPVectorTy()) {
+    Condition = getFCmpCondCode(CondCode);
+    SimplifyQuery SQ(DAG.getDataLayout(), &VPIntrin);
+    if (isKnownNeverNaN(Op2, SQ) && isKnownNeverNaN(Op1, SQ))
+      Condition = getFCmpCodeWithoutNaN(Condition);
+  } else {
+    Condition = getICmpCondCode(CondCode);
+  }
+
   EVT DestVT = DAG.getTargetLoweringInfo().getValueType(DAG.getDataLayout(),
                                                         VPIntrin.getType());
-  if (DAG.isKnownNeverNaN(Op1) && DAG.isKnownNeverNaN(Op2))
-    Condition = getFCmpCodeWithoutNaN(Condition);
-  setValue(&VPIntrin,
-           DAG.getSetCCVP(DL, DestVT, Op1, Op2, Condition, MaskOp, EVL));
+  setValue(&VPIntrin, DAG.getSetCCVP(DL, DestVT, getValue(Op1), getValue(Op2),
+                                     Condition, MaskOp, EVL));
 }
 
 void SelectionDAGBuilder::visitVectorPredicationIntrinsic(