[llvm] [LV] Vectorize selecting last IV of min/max element. (PR #141431)

[via llvm-commits]

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@@ -93,7 +140,7 @@ define i64 @test_vectorize_select_smin_first_idx(ptr %src, i64 %n) {
 ; CHECK:       [[LOOP]]:
 ; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
 ; CHECK-NEXT:    [[MIN_IDX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_IDX_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT:    [[MIN_VAL:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[MIN_VAL_NEXT:%.*]], %[[LOOP]] ]
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ayalz wrote:

Bumping initial value of reduction up from zero is mostly relevant for umin reduction.

https://github.com/llvm/llvm-project/pull/141431