[PATCH] D66157: [BasicAA] Use dereferenceability to reason about aliasing

[Johannes Doerfert via Phabricator via llvm-commits]

jdoerfert created this revision.
jdoerfert added reviewers: asbirlea, chandlerc, hfinkel, sanjoy.
Herald added subscribers: bollu, hiraditya.
Herald added a project: LLVM.

We already use the fact that an object with known size X does not alias
another objection of size Y > X before. With this commit, we use
dereferenceability information to determine a lower bound for Y and not
only rely on the user provided query size.

The result for @global_and_deref_arg_2() and @local_and_deref_ret_2()
in test/Analysis/BasicAA/dereferenceable.ll improved with this patch.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D66157

Files:
  llvm/lib/Analysis/BasicAliasAnalysis.cpp
  llvm/test/Analysis/BasicAA/dereferenceable.ll

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