InstSimplify: Strip pointer casts early.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150694 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/InstructionSimplify.cpp b/lib/Analysis/InstructionSimplify.cpp
index 9d5b74c..c9ab52c 100644
--- a/lib/Analysis/InstructionSimplify.cpp
+++ b/lib/Analysis/InstructionSimplify.cpp
@@ -1542,6 +1542,10 @@
Type *ITy = GetCompareTy(LHS); // The return type.
Type *OpTy = LHS->getType(); // The operand type.
+ // Remove pointer casts that don't change the value.
+ LHS = LHS->stripPointerCasts();
+ RHS = RHS->stripPointerCasts();
+
// icmp X, X -> true/false
// X icmp undef -> true/false. For example, icmp ugt %X, undef -> false
// because X could be 0.
@@ -1591,11 +1595,8 @@
// 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.
- Value *LHSPtr = LHS->stripPointerCasts();
- Value *RHSPtr = RHS->stripPointerCasts();
- if (isa<AllocaInst>(LHSPtr) && (isa<GlobalValue>(RHSPtr) ||
- isa<AllocaInst>(RHSPtr) ||
- isa<ConstantPointerNull>(RHSPtr)))
+ if (isa<AllocaInst>(LHS) && (isa<GlobalValue>(RHS) || isa<AllocaInst>(RHS) ||
+ isa<ConstantPointerNull>(RHS)))
// We already know that LHS != RHS.
return ConstantInt::get(ITy, CmpInst::isFalseWhenEqual(Pred));