[LoopUtils] Fix neutral value for vector.reduce.fadd

Use -0.0 instead of 0.0 as the start value. The previous use of 0.0
was fine for all existing uses of this function though, as it is
always generated with fast flags right now, and thus nsz.

1 files changed, 1 insertions, 1 deletions

diff --git a/llvm/lib/Transforms/Utils/LoopUtils.cpp b/llvm/lib/Transforms/Utils/LoopUtils.cpp
index d7cd9b1..e5d82f6 100644
--- a/llvm/lib/Transforms/Utils/LoopUtils.cpp
+++ b/llvm/lib/Transforms/Utils/LoopUtils.cpp
@@ -983,7 +983,7 @@ Value *llvm::createSimpleTargetReduction(
   case Instruction::FAdd:
     BuildFunc = [&]() {
       auto Rdx = Builder.CreateFAddReduce(
-          Constant::getNullValue(SrcVTy->getElementType()), Src);
+          ConstantFP::getNegativeZero(SrcVTy->getElementType()), Src);
       return Rdx;
     };
     break;