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

[via llvm-commits]

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@@ -93,6 +94,7 @@ define i32 @reduction(ptr %a, i64 %n, i32 %start) {
 ; NO-VP-OUTLOOP-EMPTY:
 ; NO-VP-OUTLOOP-NEXT: middle.block:
 ; NO-VP-OUTLOOP-NEXT:   EMIT vp<[[RDX:%.+]]> = compute-reduction-result ir<[[RDX_PHI]]>, ir<[[ADD]]>
+; NO-VP-OUTLOOP-NEXT:   EMIT vp<[[RDX_EX:%.+]]> = extract-from-end vp<[[RDX]]>, ir<1>
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ayalz wrote:

fine, is this extract redundant?

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