[PATCH] D91936: [BasicAA] Fix BatchAA results for phi-phi assumptions

[Nikita Popov via Phabricator via llvm-commits]

nikic created this revision.
nikic added reviewers: asbirlea, jdoerfert.
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Add a flag that disables caching when computing aliasing results potentially based on a phi-phi NoAlias assumption. We'll still insert cache entries temporarily to catch infinite recursion, but will drop them afterwards, so they won't persist in BatchAA.

Doing this doesn't seem to be a compile-time problem: https://llvm-compile-time-tracker.com/compare.php?from=221c2b8862b1e507a6e79ca2731c2f839a2fd482&to=08927349d1df1b41e525b1bcc37e53f6ff189f44&stat=instructions (There's a mild improvement because a cache update is skipped if the final recursive query is MayAlias.)


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D91936

Files:
  llvm/include/llvm/Analysis/BasicAliasAnalysis.h
  llvm/lib/Analysis/BasicAliasAnalysis.cpp
  llvm/unittests/Analysis/AliasAnalysisTest.cpp

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