[llvm] [DA] do not handle array accesses of different offsets (PR #123436)

[Michael Kruse via llvm-commits]

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@@ -10971,6 +10971,52 @@ bool ScalarEvolution::isKnownToBeAPowerOfTwo(const SCEV *S, bool OrZero,
   return all_of(Mul->operands(), NonRecursive) && (OrZero || isKnownNonZero(S));
 }
 
+bool ScalarEvolution::isKnownMultipleOf(
+    const SCEV *S, uint64_t M,
+    SmallVectorImpl<const SCEVPredicate *> &Assumptions) {
+  if (M == 0)
+    return false;
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Meinersbur wrote:

`S==0` in the context of getMinusSCEV would mean an eltSize of 0, which means memory will never be accessed which means there never is a dependency. But there isn't necessarily this context for the caller of `isKnownMultipleOf`.

This function can always return false, since it is returns true of if it is a *known* multiple. The case `0/0` is still questionable, so it is safe to return false here.

https://github.com/llvm/llvm-project/pull/123436