[llvm] 897b00f - Reuse getBinOpIdentity in createAnyOfTargetReduction [nfc]

[Philip Reames via llvm-commits]

Author: Philip Reames
Date: 2024-08-30T11:57:24-07:00
New Revision: 897b00f3c563dd3f7b8f7263c41eaebb3520ec86

URL: https://github.com/llvm/llvm-project/commit/897b00f3c563dd3f7b8f7263c41eaebb3520ec86
DIFF: https://github.com/llvm/llvm-project/commit/897b00f3c563dd3f7b8f7263c41eaebb3520ec86.diff

LOG: Reuse getBinOpIdentity in createAnyOfTargetReduction [nfc]

Consolidating code so that we have one copy instead of multiple reasoning
about identity element.  Note that we're (deliberately) not passing
the FMF flags to common utility to preserve behavior in this change.

Added: 
    

Modified: 
    llvm/lib/Transforms/Utils/LoopUtils.cpp

Removed: 
    


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diff  --git a/llvm/lib/Transforms/Utils/LoopUtils.cpp b/llvm/lib/Transforms/Utils/LoopUtils.cpp
index a49d3b0b990bc7..8a8d8afece6cb4 100644
--- a/llvm/lib/Transforms/Utils/LoopUtils.cpp
+++ b/llvm/lib/Transforms/Utils/LoopUtils.cpp
@@ -1210,6 +1210,11 @@ Value *llvm::createAnyOfTargetReduction(IRBuilderBase &Builder, Value *Src,
 Value *llvm::createSimpleTargetReduction(IRBuilderBase &Builder, Value *Src,
                                          RecurKind RdxKind) {
   auto *SrcVecEltTy = cast<VectorType>(Src->getType())->getElementType();
+  auto getIdentity = [&]() {
+    Intrinsic::ID ID = getReductionIntrinsicID(RdxKind);
+    unsigned Opc = getArithmeticReductionInstruction(ID);
+    return ConstantExpr::getBinOpIdentity(Opc, SrcVecEltTy);
+  };
   switch (RdxKind) {
   case RecurKind::Add:
   case RecurKind::Mul:
@@ -1227,10 +1232,9 @@ Value *llvm::createSimpleTargetReduction(IRBuilderBase &Builder, Value *Src,
     return Builder.CreateUnaryIntrinsic(getReductionIntrinsicID(RdxKind), Src);
   case RecurKind::FMulAdd:
   case RecurKind::FAdd:
-    return Builder.CreateFAddReduce(ConstantFP::getNegativeZero(SrcVecEltTy),
-                                    Src);
+    return Builder.CreateFAddReduce(getIdentity(), Src);
   case RecurKind::FMul:
-    return Builder.CreateFMulReduce(ConstantFP::get(SrcVecEltTy, 1.0), Src);
+    return Builder.CreateFMulReduce(getIdentity(), Src);
   default:
     llvm_unreachable("Unhandled opcode");
   }