[PATCH] D110547: [MemCpyOpt] Use EarliestEscapeInfo instead of callCapturesBefore.

[Nikita Popov via Phabricator via llvm-commits]

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The global use of BatchAA in DSE is based on the justification that DSE does not add new instructions while BatchAA is in use -- this means that even though there may be stale entries in the alias cache (stale in the sense of having the location pointing to a deleted instruction), these will not get accidentally reused by newly allocated instructions.

I don't believe that this logic holds up for MemCpyOpt, which does create new instructions. I also suspect that it may modify existing instructions in ways that could render cached alias information invalid (not sure on that though).


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  https://reviews.llvm.org/D110547/new/

https://reviews.llvm.org/D110547