An information processing apparatus operates data stored in an input register for each bit and stores a result thereof in an output register. A selector circuit selects output data of a bit from input data of 128 bits in the input register. An AND circuit outputs, only when data from a corresponding selector circuit is valid, the data to a corresponding bit of the output register. A control signal generator inputs a select signal indicating the number of a bit to be selected to each selector circuit, and also inputs a signal indicating whether data input from the selector circuit is valid or invalid to each AND circuit.