[llvm] [VPlan] Connect (MemRuntime|SCEV)Check blocks as VPlan transform (NFC). (PR #143879)

[Florian Hahn via llvm-commits]

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@@ -281,10 +283,10 @@ define void @vector_reverse_i64(ptr nocapture noundef writeonly %A, ptr nocaptur
 ; CHECK-NEXT:    %1 = call i64 @llvm.vscale.i64()
 ; CHECK-NEXT:    %2 = mul i64 %1, 4
 ; CHECK-NEXT:    %min.iters.check = icmp ult i64 %0, %2
-; CHECK-NEXT:    br i1 %min.iters.check, label %scalar.ph, label %vector.scevcheck
+; CHECK-NEXT:    br i1 %min.iters.check, label %scalar.ph, label %vector.ph
 ; CHECK-NEXT:  LV: vectorizing VPBB:ir-bb<vector.scevcheck> in BB:vector.scevcheck
 ; CHECK-NEXT:  LV: filled BB:
-; CHECK-NEXT:  vector.scevcheck: ; preds = %for.body.preheader
+; CHECK-NEXT:  vector.scevcheck: ; No predecessors!
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fhahn wrote:

Yep, at this point, it has not been connected yet; and the message is printed after executing all recipes in a block, but before connecting to predecssors.

https://github.com/llvm/llvm-project/pull/143879