[llvm] [VPlan] Retain exit conditions and edges in initial VPlan (NFC). (PR #137709)

[via llvm-commits]

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@@ -113,6 +113,9 @@ VPBasicBlock *PlainCFGBuilder::getOrCreateVPBB(BasicBlock *BB) {
     return VPBB;
   }
 
+  if (!TheLoop->contains(BB))
+    return Plan->getExitBlock(BB);
+
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ayalz wrote:

How about populating BB2VPBB with Plan's exit blocks on PlainCFGBuilder's construction, to fold this check with the one above?

https://github.com/llvm/llvm-project/pull/137709