diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp index 79a551f70c8..067a884bc9d 100644 --- a/lib/Transforms/Scalar/InstructionCombining.cpp +++ b/lib/Transforms/Scalar/InstructionCombining.cpp @@ -342,6 +342,10 @@ Instruction *InstCombiner::visitMul(BinaryOperator &I) { } } + if (Value *Op0v = dyn_castNegVal(Op0)) // -X * -Y = X*Y + if (Value *Op1v = dyn_castNegVal(I.getOperand(1))) + return BinaryOperator::create(Instruction::Mul, Op0v, Op1v); + return Changed ? &I : 0; }