[llvm-branch-commits] [llvm] AMDGPU: Make sqrt and rsq intrinsics propagate poison (PR #130914)

[Shilei Tian via llvm-branch-commits]

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@@ -548,6 +548,8 @@ GCNTTIImpl::instCombineIntrinsic(InstCombiner &IC, IntrinsicInst &II) const {
   case Intrinsic::amdgcn_sqrt:
   case Intrinsic::amdgcn_rsq: {
     Value *Src = II.getArgOperand(0);
+    if (isa<PoisonValue>(Src))
+      return IC.replaceInstUsesWith(II, Src);
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shiltian wrote:

Why does `undef` give `QNaN` while `poison` give `poison`?

https://github.com/llvm/llvm-project/pull/130914