[llvm] [VPlan] Impl VPlan-based pattern match for ExtendedRed and MulAccRed (NFCI) (PR #113903)

[Florian Hahn via llvm-commits]

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@@ -1504,49 +1504,50 @@ void VPWidenCastRecipe::execute(VPTransformState &State) {
     setFlags(CastOp);
 }
 
+// Computes the CastContextHint from a recipes that may access memory.
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fhahn wrote:

```suggestion
/// Computes the CastContextHint for a recipe.
```

It computes the win for any recipe I think

https://github.com/llvm/llvm-project/pull/113903