A data processing apparatus that can perform high-speed interrupt processing, and a method of controlling such a data processing apparatus are provided. This data processing apparatus includes: an execution unit that executes an instruction read out from a memory; a general register connected to the execution unit; a shadow register also connected to the execution unit; and selectors that allocate to the shadow register a part or the entire part of an address already allocated to the general register when an interrupt is executed in accordance with the instruction.