An apparatus and method are provided for efficiently performing arithmetic operations that include at least a multiplication operation. The apparatus comprises processing circuitry to perform data processing operations, and instruction decode circuitry responsive to program instructions to generate control signals to control the processing circuitry to perform the data processing operations. In response to an arithmetic operation with shift instruction specifying performance of an arithmetic operation comprising at least a multiplication operation, and having a field which provides a programmable shift indication, the instruction decode circuitry is configured to control the processing circuitry to perform the arithmetic operation during which an intermediate value is produced, and to select a target portion of the intermediate value based on an output window determined from the programmable shift indication.