[llvm] [ConstraintElim] Bail out non-dedicated exits when adding exiting conditions (PR #116627)

[Nikita Popov via llvm-commits]

================
@@ -1034,18 +1034,21 @@ void State::addInfoForInductions(BasicBlock &BB) {
       DTN, CmpInst::ICMP_SLT, PN, B,
       ConditionTy(CmpInst::ICMP_SLE, StartValue, B)));
 
-  // Try to add condition from header to the exit blocks. When exiting either
-  // with EQ or NE in the header, we know that the induction value must be u<=
-  // B, as other exits may only exit earlier.
+  // Try to add condition from header to the dedicated exit blocks. When exiting
+  // either with EQ or NE in the header, we know that the induction value must
+  // be u<= B, as other exits may only exit earlier.
   assert(!StepOffset.isNegative() && "induction must be increasing");
   assert((Pred == CmpInst::ICMP_EQ || Pred == CmpInst::ICMP_NE) &&
          "unsupported predicate");
   ConditionTy Precond = {CmpInst::ICMP_ULE, StartValue, B};
   SmallVector<BasicBlock *> ExitBBs;
   L->getExitBlocks(ExitBBs);
   for (BasicBlock *EB : ExitBBs) {
-    WorkList.emplace_back(FactOrCheck::getConditionFact(
-        DT.getNode(EB), CmpInst::ICMP_ULE, A, B, Precond));
+    // bail out non-dedicated exits.
+    if (DT.dominates(PN, EB)) {
----------------
nikic wrote:

```suggestion
    if (DT.dominates(&BB, EB)) {
```

https://github.com/llvm/llvm-project/pull/116627