[llvm] [llvm][UnifyLoopExits] Avoid optimization if no exit block is found (PR #165343)

[Miguel Saldivar via llvm-commits]

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@@ -299,6 +299,8 @@ std::pair<BasicBlock *, bool> ControlFlowHub::finalize(
       Outgoing.insert(Succ1);
   }
 
+  assert(Outgoing.size());
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Saldivarcher wrote:

Done!

https://github.com/llvm/llvm-project/pull/165343