[llvm] [DSE] Fix non-determinism due to address reuse (PR #84943)

[Florian Hahn via llvm-commits]

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@@ -2167,14 +2171,15 @@ static bool eliminateDeadStores(Function &F, AliasAnalysis &AA, MemorySSA &MSSA,
     unsigned PartialLimit = MemorySSAPartialStoreLimit;
     // Worklist of MemoryAccesses that may be killed by KillingDef.
     SmallSetVector<MemoryAccess *, 8> ToCheck;
+    SmallPtrSet<MemoryAccess *, 8> Deleted;
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fhahn wrote:

Could you add a comment here explaining why this extra set is needed here?

https://github.com/llvm/llvm-project/pull/84943