Fix a rather nasty regression from r150690: LHS != RHS does not imply LHS->stripPointerCasts() != RHS->stripPointerCasts().

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150863 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Eli Friedman
2012-02-18 03:29:25 +00:00
parent 5bfd969208
commit 2c3acb0e27
2 changed files with 12 additions and 1 deletions

View File

@@ -1593,10 +1593,11 @@ static Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS,
// the compare, and if only one of them is then we moved it to RHS already.
Value *LHSPtr = LHS->stripPointerCasts();
Value *RHSPtr = RHS->stripPointerCasts();
if (LHSPtr == RHSPtr)
return ConstantInt::get(ITy, CmpInst::isTrueWhenEqual(Pred));
if (isa<AllocaInst>(LHSPtr) && (isa<GlobalValue>(RHSPtr) ||
isa<AllocaInst>(RHSPtr) ||
isa<ConstantPointerNull>(RHSPtr)))
// We already know that LHS != RHS.
return ConstantInt::get(ITy, CmpInst::isFalseWhenEqual(Pred));
// If we are comparing with zero then try hard since this is a common case.