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

[via llvm-commits]

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@@ -9105,8 +9205,10 @@ void LoopVectorizationPlanner::adjustRecipesForReductions(
         VPInstruction::ComputeReductionResult, {PhiR, NewExitingVPV}, ExitDL);
     FinalReductionResult->insertBefore(*MiddleVPBB, IP);
     OrigExitingVPV->replaceUsesWithIf(
-        FinalReductionResult,
-        [](VPUser &User, unsigned) { return isa<VPLiveOut>(&User); });
+        FinalReductionResult, [](VPUser &User, unsigned) {
+          auto *R = dyn_cast<VPInstruction>(&User);
+          return R && R->getOpcode() == VPInstruction::ExtractFromEnd;
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ayalz wrote:

Use match?

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