Patent ID: 6199156
Filing Date: 2001-03-06
Classification: G06F

Abstract:
A method in a data processing system of restoring a register having a previous contents saved in a memory utilizing a register valid flag corresponding to the register and having a first logical state and a second logical state, said method comprising:A) setting the register valid flag to the first logical state when preforming processor context switch; andB) when responding to a requirement by a functional unit to read the register in response to execution of an instruction explicitly referencing the register for a current contents of the resister, performing substeps of:1) testing whether the register valid flag is in the first logical state or the second logical state,2) if the register valid flag is in the first logical state,a) loading the previous contents into the register as the current contents of the register, andb) setting the register valid flag to the second logical state, and3) providing the current contents of the register to the functional unit.