Index: lib/Transforms/InstCombine/InstCombineShifts.cpp =================================================================== --- lib/Transforms/InstCombine/InstCombineShifts.cpp +++ lib/Transforms/InstCombine/InstCombineShifts.cpp @@ -340,17 +340,6 @@ // purpose is to compute bits we don't care about. uint32_t TypeBits = Op0->getType()->getScalarSizeInBits(); - // shl i32 X, 32 = 0 and srl i8 Y, 9 = 0, ... just don't eliminate - // a signed shift. - // - if (COp1->uge(TypeBits)) { - if (I.getOpcode() != Instruction::AShr) - return ReplaceInstUsesWith(I, Constant::getNullValue(Op0->getType())); - // ashr i32 X, 32 --> ashr i32 X, 31 - I.setOperand(1, ConstantInt::get(I.getType(), TypeBits-1)); - return &I; - } - // ((X*C1) << C2) == (X * (C1 << C2)) if (BinaryOperator *BO = dyn_cast(Op0)) if (BO->getOpcode() == Instruction::Mul && isLeftShift)