From cb45bd9cb33932e79cceaca3ba560182ba329f72 Mon Sep 17 00:00:00 2001 From: Dan Gohman Date: Thu, 8 Apr 2010 18:11:50 +0000 Subject: Pointers to zero-sized objects don't point to overlapping objects. llvm-svn: 100789 --- llvm/lib/Analysis/BasicAliasAnalysis.cpp | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'llvm/lib/Analysis') diff --git a/llvm/lib/Analysis/BasicAliasAnalysis.cpp b/llvm/lib/Analysis/BasicAliasAnalysis.cpp index 31a649d5cc4..cfe7a1c0ca2 100644 --- a/llvm/lib/Analysis/BasicAliasAnalysis.cpp +++ b/llvm/lib/Analysis/BasicAliasAnalysis.cpp @@ -655,6 +655,11 @@ BasicAliasAnalysis::aliasPHI(const PHINode *PN, unsigned PNSize, AliasAnalysis::AliasResult BasicAliasAnalysis::aliasCheck(const Value *V1, unsigned V1Size, const Value *V2, unsigned V2Size) { + // If either of the memory references is empty, it doesn't matter what the + // pointer values are. + if (V1Size == 0 || V2Size == 0) + return NoAlias; + // Strip off any casts if they exist. V1 = V1->stripPointerCasts(); V2 = V2->stripPointerCasts(); -- cgit v1.2.3