diff options
| -rw-r--r-- | lib/VMCore/ConstantFold.cpp | 23 | ||||
| -rw-r--r-- | test/Transforms/InstCombine/2008-05-17-FoldIntToPtr.ll | 8 |
2 files changed, 31 insertions, 0 deletions
diff --git a/lib/VMCore/ConstantFold.cpp b/lib/VMCore/ConstantFold.cpp index 0913c481ad..e381f3b102 100644 --- a/lib/VMCore/ConstantFold.cpp +++ b/lib/VMCore/ConstantFold.cpp @@ -1029,6 +1029,29 @@ static ICmpInst::Predicate evaluateICmpRelation(const Constant *V1, } break; + case Instruction::PtrToInt: + case Instruction::IntToPtr: + // inttoptr(x1) != inttoptr(x2) iff x1 != x2 + if (const ConstantExpr *CE2 = dyn_cast<ConstantExpr>(V2)) + if (CE1->getOpcode() == CE2->getOpcode()) { + Constant *Op1 = const_cast<Constant*>(CE1Op0); + Constant *Op2 = CE2->getOperand(0); + if (CE1Op->getType() == CE2Op->getType()) { + ConstantInt *R = 0; + + ICmpInst::Predicate pred = ICmpInst::ICMP_EQ; + R = dyn_cast<ConstantInt>(ConstantExpr::getICmp(pred, Op1, Op2)); + if (R && !R->isZero()) + return pred; + + pred = ICmpInst::ICMP_NE; + R = dyn_cast<ConstantInt>(ConstantExpr::getICmp(pred, Op1, Op2)); + if (R && !R->isZero()) + return pred; + } + } + break; + case Instruction::GetElementPtr: // Ok, since this is a getelementptr, we know that the constant has a // pointer type. Check the various cases. diff --git a/test/Transforms/InstCombine/2008-05-17-FoldIntToPtr.ll b/test/Transforms/InstCombine/2008-05-17-FoldIntToPtr.ll new file mode 100644 index 0000000000..1d93294fe4 --- /dev/null +++ b/test/Transforms/InstCombine/2008-05-17-FoldIntToPtr.ll @@ -0,0 +1,8 @@ +; RUN: llvm-as < %s | opt -instcombine | llvm-dis | grep {ret i1 false} +; PR2329 + +define i1 @f() { + %x = icmp eq i8* inttoptr (i32 1 to i8*), inttoptr (i32 2 to i8*) + ret i1 %x +} + |