Patent ID: 8539208
Filing Date: 2013-09-17
Classification: G06F

Abstract:
1. An arithmetic processing unit comprising: an arithmetic section configured to perform arithmetic processing; a register file including the control section configured to output the window address information for the current window selecting unit of the register file to select a window, wherein the current window selecting unit comprises: a first local register reading port configured to select a register based on the window address information from local registers in local register groups whose window number is even, the local registers being working registers of the subroutine; a second local register reading port configured to select a register based on the window address information from local registers in local register groups whose window number is odd, the local registers being working registers of the subroutine; a first out-register reading port configured to select a register based on the window address information from out-registers in out-register groups whose window number is even, the out-registers being used for passing an argument when the subroutine is called; a second out-register reading port configured to select a register based on the window address information from out-registers in out-register groups whose window number is odd, the out-registers being used for passing an argument when the subroutine is called; and a third out-register reading port configured to select a register based on the window address information from out-registers in out-register groups used for passing an argument when the subroutine is called.