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

[Florian Hahn 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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fhahn wrote:

The live-outs both before and after the patch were for the phis in the scalar loop (%for.1, %for.2), but previously they were created during `adjustFixedOrderRecurrence`

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