[llvm] [VPlan] Optimize more IV increment exit users by using a map (PR #147016)

[Mel Chen via llvm-commits]

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@@ -368,11 +368,11 @@ define void @wide_add_induction_step_live_in(ptr %dst, i64 %N, i16 %off) {
 ; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
 ; CHECK:       [[SCALAR_PH]]:
 ; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
-; CHECK-NEXT:    [[BC_RESUME_VAL3:%.*]] = phi i16 [ [[TMP0]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
+; CHECK-NEXT:    [[BC_RESUME_VAL5:%.*]] = phi i16 [ [[TMP0]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
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Mel-Chen wrote:

This case remains unchanged. I thinlk we don't have to update it.

https://github.com/llvm/llvm-project/pull/147016