InstSimplify: Ignore pointer casts when constant folding compares between pointers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150690 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/InstructionSimplify.cpp b/lib/Analysis/InstructionSimplify.cpp
index 7656220..9d5b74c 100644
--- a/lib/Analysis/InstructionSimplify.cpp
+++ b/lib/Analysis/InstructionSimplify.cpp
@@ -1591,8 +1591,11 @@
// to the case where LHS is a global variable address or null is pointless,
// since if both LHS and RHS are constants then we already constant folded
// the compare, and if only one of them is then we moved it to RHS already.
- if (isa<AllocaInst>(LHS) && (isa<GlobalValue>(RHS) || isa<AllocaInst>(RHS) ||
- isa<ConstantPointerNull>(RHS)))
+ Value *LHSPtr = LHS->stripPointerCasts();
+ Value *RHSPtr = RHS->stripPointerCasts();
+ 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));