[llvm] LAA: thoroughly clarify stride-versioning code (NFC) (PR #97075)

[Ramkumar Ramachandra via llvm-commits]

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@@ -2955,40 +2956,35 @@ void LoopAccessInfo::collectStridedAccess(Value *MemAccess) {
   // of various possible stride specializations, considering the alternatives
   // of using gather/scatters (if available).
 
-  const SCEV *MaxBTC = PSE->getSymbolicMaxBackedgeTakenCount();
+  const SCEV *BTC = PSE->getSymbolicMaxBackedgeTakenCount();
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artagnon wrote:

Small caveat: I think this should be `getBackedgeTakenCount`, the exact version, and not the symbolic-max version. However, it's not going to be easy to cook up a test to support this change, but I can think about it in a follow-up.

https://github.com/llvm/llvm-project/pull/97075