[llvm] [VPlan] Replace ExtractLast(Elem|LanePerPart) with ExtractLast(Lane/Part) (PR #164124)

[via llvm-commits]

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@@ -39,7 +39,9 @@ define i32 @print_partial_reduction(ptr %a, ptr %b) {
 ; CHECK-NEXT: Successor(s): middle.block
 ; CHECK-EMPTY:
 ; CHECK-NEXT: middle.block:
-; CHECK-NEXT:   EMIT vp<[[RED_RESULT:%.+]]> = compute-reduction-result ir<[[ACC]]>, vp<[[REDUCE]]>
+; CHECK-NEXT:   EMIT vp<[[RED_RESULT_PART:%.+]]> = compute-reduction-result ir<[[ACC]]>, vp<[[REDUCE]]>
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ayalz wrote:

Would be good to avoid/eliminate redundant extracts (TODO?).

https://github.com/llvm/llvm-project/pull/164124