Patent ID: 7093110

Claim:
A register file having a master register file and a working register file, data used for a process for an instruction being transferred from the master register file and stored in the working register file, data used for a process for an instruction being read from the working register file, comprising: a current window pointer unit pointing a current window position for accessing the master register file; a working register window current pointer unit pointing to a current window position for accessing the working register file; and a unit transferring data from the master register file to the working register file which contains all data of current, preceding and following register windows and updating data of the working register file when the current window pointer is changed so that the master register file stores data of all register windows of an information processing apparatus and the working register file stores data of a window pointed by the current window pointer and data of windows followed and preceded by the window pointed by the current window pointer, wherein each register window comprises a global register, out register, in register, and local register and the out register of the preceding register window overlaps with the in register of the current register window and the out register of the current register window overlaps with the in register of the following register window.