PROCESSOR, METHOD FOR OPERATING PROCESSOR, AND INFORMATION PROCESSING SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide a method and device for prohibiting fetch throttling when a processor encounters a branch instruction with low reliability in an information processing system. SOLUTION: The information processing system comprises a processor 100 which throttles an instruction fetch unit 110 whenever an instruction group in a branch instruction queue (BIQ) 205 shows a reliability in accuracy of branch prediction of a branch instruction therein, but shows that the reliability is lower than a first predetermined threshold of reliability threshold. In one embodiment, the processor 100 includes a fetch throttle controller 200 which prohibits fetch throttling by the instruction fetch unit 110 when the reliability in accuracy of branch prediction for a specific currently issued branch instruction is lower than a second predetermined threshold of reliability threshold. COPYRIGHT: (C)2009,JPO&INPIT