[llvm] [LV] Decompose WidenIntOrFPInduction into phi and update recipes (PR #82021)

[Mel Chen via llvm-commits]

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@@ -48,7 +49,7 @@ for.end:
 ; CHECK-NEXT: <x1> vector loop: {
 ; CHECK-NEXT: vector.body:
 ; CHECK-NEXT:   EMIT vp<[[CAN_IV:%.+]]> = CANONICAL-INDUCTION
-; CHECK-NEXT:   WIDEN-INDUCTION %iv = phi 0, %iv.next, ir<1>
+; CHECK-NEXT:   WIDEN-INDUCTION ir<%iv> = phi ir<0>, vp<[[NEXT_WIV:%.+]]>, ir<1>
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Mel-Chen wrote:

What is the meaning of `ir<1>`?
Is it necessary after this patch decompose `WidenIntOrFPInduction`?

https://github.com/llvm/llvm-project/pull/82021