[llvm] [LV] Keep duplicate recipes in VPExpressionRecipe (PR #156976)

[Florian Hahn via llvm-commits]

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@@ -3013,8 +3015,11 @@ class VPExpressionRecipe : public VPSingleDefRecipe {
                            {Ext0, Ext1, Mul, Red}) {}
 
   ~VPExpressionRecipe() override {
-    for (auto *R : reverse(ExpressionRecipes))
-      delete R;
+    SmallSet<VPSingleDefRecipe *, 4> ExpressionRecipesSeen;
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fhahn wrote:

```suggestion
    SmallSetPtrSet<VPSingleDefRecipe *, 4> ExpressionRecipesSeen;
```

https://github.com/llvm/llvm-project/pull/156976