[llvm] [VPlan] Introduce explicit ExtractFromEnd recipes for live-outs. (PR #100658)

[via llvm-commits]

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@@ -8884,10 +8982,12 @@ void LoopVectorizationPlanner::adjustRecipesForReductions(
     for (unsigned I = 0; I != Worklist.size(); ++I) {
       VPSingleDefRecipe *Cur = Worklist[I];
       for (VPUser *U : Cur->users()) {
-        auto *UserRecipe = dyn_cast<VPSingleDefRecipe>(U);
-        if (!UserRecipe) {
-          assert(isa<VPLiveOut>(U) &&
-                 "U must either be a VPSingleDef or VPLiveOut");
+        auto *UserRecipe = cast<VPSingleDefRecipe>(U);
+        if (!UserRecipe->getParent()->getParent()) {
+          assert(cast<VPInstruction>(U) &&
+                 cast<VPInstruction>(U)->getOpcode() ==
+                     VPInstruction::ExtractFromEnd &&
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ayalz wrote:

Use match?
The excessively long method deserves to be shortened rather than further extended.

https://github.com/llvm/llvm-project/pull/100658