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

[Sander de Smalen via llvm-commits]

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@@ -2797,25 +2796,42 @@ VPExpressionRecipe::VPExpressionRecipe(
       R->removeFromParent();
   }
 
+  // Keep track of how many instances of each recipe occur in the recipe list
+  SmallMapVector<VPSingleDefRecipe *, unsigned, 4> ExpressionRecipeCounts;
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sdesmalen-arm wrote:

I'm a bit worried about a slightly different case, where the same (external) input operand is shared by different expression recipes. I don't think there would be an easy way to test that at the moment, but I can see that happening with other kinds of expressions in the future.

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