COMPUTER PROCESSOR SYSTEM

摘要

PROBLEM TO BE SOLVED: To prevent processors from being serial in most cases after the execution of STOSM or STNSM instruction and to attain improvement in performance by providing a termination interrupt logic for executing a specified instruction to change the system mask field of a program condition word without making it serial. SOLUTION: Parallelly with all the operation, the termination interrupt logic 11 continuously monitors and controls the execution completion of all the instructions and the write of the result. Besides, an asynchronous interruption logic 12 continuously monitors the presence/absence of asynchronous interruption under holding and when there is such interruption, it is presented to the termination interrupt logic 11. A PSW executing device 13 receives data to be loaded to a PSW from a fixed point executing device 7. This device 7 is provided with a logic for monitoring the change of a system mask bit. When the STOSM or STNSM instruction is under executing, this device 7 reports it to the termination interrupt logic 11 provided with an end counter.