[llvm] [VPlan] Model branch cond to enter scalar epilogue in VPlan. (PR #92651)

[via llvm-commits]

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@@ -697,7 +700,7 @@ static std::pair<VPBlockBase *, VPBlockBase *> cloneSESE(VPBlockBase *Entry) {
   }
 #endif
 
-  return std::make_pair(Old2NewVPBlocks[Entry], Old2NewVPBlocks[Exiting]);
+  return std::make_pair(Old2NewVPBlocks[Entry], InRegion ? Old2NewVPBlocks[Exiting] : nullptr);
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ayalz wrote:

Worth asserting that Exiting is non-null if (and only if) InRegion?
 
```suggestion
  return std::make_pair(Old2NewVPBlocks[Entry], Exiting ? Old2NewVPBlocks[Exiting] : nullptr);
```

https://github.com/llvm/llvm-project/pull/92651