[llvm] [VPlan] Introduce ExitPhi VPInstruction, use to create phi for FOR. (PR #94760)

[via llvm-commits]

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@@ -43,10 +43,12 @@ define void @test_chained_first_order_recurrences_1(ptr %ptr) {
 ; CHECK-NEXT:  No successors
 ; CHECK-EMPTY:
 ; CHECK-NEXT:  scalar.ph
+; CHECK-NEXT:    EMIT vp<[[RESUME_1_P:%.*]]> = exit-phi vp<[[RESUME_1]]>, ir<22>
+; CHECK-NEXT:    EMIT vp<[[RESUME_2_P:%.*]]> = exit-phi vp<[[RESUME_2]]>, ir<33>
 ; CHECK-NEXT:  No successors
 ; CHECK-EMPTY:
-; CHECK-NEXT: Live-out i16 %for.1 = vp<[[RESUME_1]]>
-; CHECK-NEXT: Live-out i16 %for.2 = vp<[[RESUME_2]]>
+; CHECK-NEXT: Live-out i16 %for.1 = vp<[[RESUME_1_P]]>
+; CHECK-NEXT: Live-out i16 %for.2 = vp<[[RESUME_2_P]]>
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ayalz wrote:

Ah, right, thanks for clarifying.

Would be good (as separate patch) to list live-outs corresponding to exit-block next to it, and those corresponding to scalar header next to it - if/when the latter is also modeled as a VPIRBasicBlock.

https://github.com/llvm/llvm-project/pull/94760