The present disclosure provides a processing device and method. The device includes: an input/output module, a controller module, a computing module, and a storage module. The input/output module is configured to store and transmit input and output data; the controller module is configured to decode a computation instruction into a control signal to control other modules to perform operation; the computing module is configured to perform four arithmetic operation, logical operation, shift operation, and complement operation on data; and the storage module is configured to temporarily store instructions and data. The present disclosure can execute a composite scalar instruction accurately and efficiently.