Revert r131781 again. Apparently there is more going on here.

llvm-svn: 132625

1 files changed, 1 insertions, 11 deletions

diff --git a/llvm/lib/Analysis/BasicAliasAnalysis.cpp b/llvm/lib/Analysis/BasicAliasAnalysis.cpp
index 3d10a5fd4d7..24297d4a0f3 100644
--- a/llvm/lib/Analysis/BasicAliasAnalysis.cpp
+++ b/llvm/lib/Analysis/BasicAliasAnalysis.cpp
@@ -944,17 +944,7 @@ BasicAliasAnalysis::aliasGEP(const GEPOperator *GEP1, uint64_t V1Size,
       return NoAlias;
   }
   
-  // Statically, we can see that the base objects are the same, but the
-  // pointers have dynamic offsets which we can't resolve. And none of our
-  // little tricks above worked.
-  //
-  // TODO: Returning PartialAlias instead of MayAlias is a mild hack; the
-  // practical effect of this is protecting TBAA in the case of dynamic
-  // indices into arrays of unions. An alternative way to solve this would
-  // be to have clang emit extra metadata for unions and/or union accesses.
-  // A union-specific solution wouldn't handle the problem for malloc'd
-  // memory however.
-  return PartialAlias;
+  return MayAlias;
 }
 
 static AliasAnalysis::AliasResult