[llvm] [LoopVectorize] Improve algorithm for hoisting runtime checks (PR #73515)

[Florian Hahn via llvm-commits]

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@@ -346,7 +346,9 @@ void RuntimePointerChecking::tryToCreateDiffCheck(
     auto *SinkStartAR = cast<SCEVAddRecExpr>(SinkStartInt);
     const Loop *StartARLoop = SrcStartAR->getLoop();
     if (StartARLoop == SinkStartAR->getLoop() &&
-        StartARLoop == InnerLoop->getParentLoop()) {
+        StartARLoop == InnerLoop->getParentLoop() &&
+        SrcStartAR->getStepRecurrence(*SE) !=
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fhahn wrote:

Would be good to add a comment here explaining the check

https://github.com/llvm/llvm-project/pull/73515