diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index 6654daff37d..f0961de5274 100644
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -1970,10 +1970,10 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) {
         return BinaryOperator::createAnd(Op0, NewNot);
       }
 
-      // -(X sdiv C)  -> (X sdiv -C)
+      // 0 - (X sdiv C)  -> (X sdiv -C)
       if (Op1I->getOpcode() == Instruction::Div)
         if (ConstantSInt *CSI = dyn_cast<ConstantSInt>(Op0))
-          if (!CSI->isNullValue())
+          if (CSI->isNullValue())
             if (Constant *DivRHS = dyn_cast<Constant>(Op1I->getOperand(1)))
               return BinaryOperator::createDiv(Op1I->getOperand(0),
                                                ConstantExpr::getNeg(DivRHS));