Fix nasty bug in ::isNeg()

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@4470 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 1 insertions, 1 deletions

diff --git a/lib/VMCore/iOperators.cpp b/lib/VMCore/iOperators.cpp
index 5aa9714eb9..5a88986135 100644
--- a/lib/VMCore/iOperators.cpp
+++ b/lib/VMCore/iOperators.cpp
@@ -91,7 +91,7 @@ static inline bool isConstantAllOnes(const Value *V) {
 bool BinaryOperator::isNeg(const Value *V) {
   if (const BinaryOperator *Bop = dyn_cast<BinaryOperator>(V))
     return Bop->getOpcode() == Instruction::Sub &&
-      isa<Constant>(Bop->getOperand(0)) && cast<Constant>(V)->isNullValue();
+      Bop->getOperand(0) == Constant::getNullValue(Bop->getType());
   return false;
 }