[PATCH] D27034: [AliasAnalysis] Teach BasicAA about memcpy.

[Hal Finkel via Phabricator via llvm-commits]

hfinkel accepted this revision.
hfinkel added inline comments.


================
Comment at: lib/Analysis/BasicAliasAnalysis.cpp:777
+
+    if ((SrcAA = getBestAAResults().alias(MemoryLocation::getForSource(Inst),
+                                          Loc)) == MustAlias)
----------------
Please add a comment here explaining why you can return MRI_Ref without even checking the destination (i.e. that you're relying on the memcpy semantics which forbid overlapping memory). With that, this LGTM.

We really should also add similar logic here for memmove and memset. Would you do this as follow-up?



Repository:
  rL LLVM

https://reviews.llvm.org/D27034