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

[Nikita Popov via llvm-commits]

================
@@ -346,7 +346,10 @@ void RuntimePointerChecking::tryToCreateDiffCheck(
     auto *SinkStartAR = cast<SCEVAddRecExpr>(SinkStartInt);
     const Loop *StartARLoop = SrcStartAR->getLoop();
     if (StartARLoop == SinkStartAR->getLoop() &&
-        StartARLoop == InnerLoop->getParentLoop()) {
+        StartARLoop == InnerLoop->getParentLoop() &&
+        !SE->isKnownPredicate(ICmpInst::ICMP_EQ,
+                              SrcStartAR->getStepRecurrence(*SE),
+                              SinkStartAR->getStepRecurrence(*SE))) {
----------------
nikic wrote:

```suggestion
        SrcStartAR->getStepRecurrence(*SE) != SinkStartAR->getStepRecurrence(*SE)) {
```
Don't use isKnownPredicate() for ICMP_EQ.

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