[PATCH] D97676: [DSE] Extending isOverwrite to support offsetted fully overlapping stores

[Matteo Favaro via Phabricator via llvm-commits]

fvrmatteo marked an inline comment as done.
fvrmatteo added inline comments.


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Comment at: llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp:475
+  // If we hit a partial alias we may have a full overwrite
+  if (AA.alias(Later, Earlier) == AliasResult::PartialAlias) {
+    int64_t Off = AA.getClobberOffset(Later, Earlier).getValueOr(0);
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nikic wrote:
> You are performing two queries here, one in AA.isMustAlias above and another here. While caching mitigates some of the cost, it's better to only call AA.alias() and then check if the result is MustAlias/PartialAlias.
Thanks, I completely overlooked it!


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