[llvm] [ConstraintElim] Generalize IV logic to chain of exiting blocks. (PR #108031)

[Yingwei Zheng via llvm-commits]

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@@ -931,6 +932,8 @@ void State::addInfoForInductions(BasicBlock &BB) {
   else
     return;
 
+  assert(InLoopSucc != L->getHeader() &&
+         "Cannot inject condition back to loop header");
   if (!L->contains(InLoopSucc) || !L->isLoopExiting(&BB) || InLoopSucc == &BB)
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dtcxzyw wrote:

`!L->isLoopExiting(&BB)` always evaluates to false after this patch. You can replace it with an assertion here.



https://github.com/llvm/llvm-project/pull/108031