[llvm] [SLP] Make getSameOpcode support interchangeable instructions. (PR #127450)

[Han-Kuan Chen via llvm-commits]

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@@ -1035,16 +1035,15 @@ class InterchangeableBinOp {
   }
 };
 
-static std::optional<InterchangeableBinOp> isConvertible(Instruction *From,
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HanKuanChen wrote:

these functions are in anonymous namespace already

https://github.com/llvm/llvm-project/pull/127450