Patent ID: 6336184
Filing Date: 2002-01-01
Classification: G06F

Abstract:
In an information handling system in which a processor executing a program of instructions has an execution state defined by state information stored in a program context area, the program context area including an instruction address field for storing the address of the next instruction to be executed, a method of facilitating transfer of control from a user program to a trap program while saving state information relating to the user program, comprising the steps of:storing a trap control block specifying a trap save area outside of the program context area for storing state information relating to the user program and specifying an address of a trap program; decoding a trap instruction in the user program; in response to decoding the trap instruction in the user program: (1) copying current state information from the program context area to the trap save area to save state information relating to the user program; (2) storing an address of the trap control block in the program context area; and (3) copying the specified trap program address into the instruction address field of the program context area to transfer control to the trap program at the specified address.