[llvm] [InstCombine] Propagate poison pow[i] (PR #146750)

[Luke Lau via llvm-commits]

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@@ -33,7 +33,7 @@ define void @powi(double %V, ptr%P) {
 define void @powi_i16(float %V, ptr%P) {
 ; CHECK-LABEL: @powi_i16(
 ; CHECK-NEXT:    store volatile float 1.000000e+00, ptr [[P:%.*]], align 4
-; CHECK-NEXT:    store volatile float [[V:%.*]], ptr [[P]], align 4
+; CHECK-NEXT:    store volatile float [[D:%.*]], ptr [[P]], align 4
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lukel97 wrote:

Unrelated change?

```suggestion
; CHECK-NEXT:    store volatile float [[V:%.*]], ptr [[P]], align 4
```

https://github.com/llvm/llvm-project/pull/146750