diff --git a/llvm/lib/Transforms/Scalar/InstructionCombining.cpp b/llvm/lib/Transforms/Scalar/InstructionCombining.cpp index 838b33cb23c7..864b2fa5ee05 100644 --- a/llvm/lib/Transforms/Scalar/InstructionCombining.cpp +++ b/llvm/lib/Transforms/Scalar/InstructionCombining.cpp @@ -2702,7 +2702,8 @@ Instruction *InstCombiner::visitMul(BinaryOperator &I) { Context->getConstantInt(Op0->getType(), Val.logBase2())); } } else if (isa(Op1->getType())) { - // TODO: If Op1 is all zeros and Op0 is all finite, return all zeros. + if (Op1->isNullValue()) + return ReplaceInstUsesWith(I, Op1); if (ConstantVector *Op1V = dyn_cast(Op1)) { if (Op1V->isAllOnesValue()) // X * -1 == 0 - X diff --git a/llvm/test/Transforms/InstCombine/mul.ll b/llvm/test/Transforms/InstCombine/mul.ll index 9b5f7a5c5efc..cd13803d3103 100644 --- a/llvm/test/Transforms/InstCombine/mul.ll +++ b/llvm/test/Transforms/InstCombine/mul.ll @@ -83,3 +83,8 @@ define internal void @test13(<4 x float>*) { store <4 x float> %3, <4 x float>* %0, align 1 ret void } + +define <16 x i8> @test14(<16 x i8> %a) { + %b = mul <16 x i8> %a, zeroinitializer + ret <16 x i8> %b +}