[llvm] [VPlan] Replace VPRecipeOrVPValue with VP2VP recipe simplification. (PR #76090)

[via llvm-commits]

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@@ -9079,6 +9043,9 @@ void LoopVectorizationPlanner::adjustRecipesForReductions(
         LinkVPBB->insert(FMulRecipe, CurrentLink->getIterator());
         VecOp = FMulRecipe;
       } else {
+        if (PhiR->isInLoop() && isa<VPBlendRecipe>(CurrentLink))
+          continue;
+
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ayalz wrote:

Replace the blend here by its non-header-phi operand (possibly after the loop if needed, and/or updating PreviousLink), as mentioned below?

https://github.com/llvm/llvm-project/pull/76090