[llvm] [InstCombine] optimize powi(X,Y) * X with Ofast (PR #69998)

[Matt Arsenault via llvm-commits]

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@@ -571,6 +571,50 @@ Instruction *InstCombinerImpl::foldFPSignBitOps(BinaryOperator &I) {
   return nullptr;
 }
 
+Instruction *InstCombinerImpl::foldPowiReassoc(BinaryOperator &I) {
+  Value *X, *Y, *Z;
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arsenm wrote:

Sink these down where they are used, looks like shadowing now 

https://github.com/llvm/llvm-project/pull/69998