Processor and method for selectively processing instruction to be read using instruction code already in pipeline or already stored in prefetch buffer

Abstract

There is provided a processor including: an instruction pipeline pipeline-processing an instruction code; a comparison unit that compares an instruction code in the instruction pipeline or in an instruction prefetch buffer and an instruction code to be read next from an instruction cache memory or from a main memory, to judge whether or not the instruction codes are identical with each other; and a control unit whose control when the instruction codes are identical with each other is to read the instruction code neither from the instruction cache memory nor from the main memory but to process the instruction code stored in the instruction pipeline or in the instruction prefetch buffer again in the instruction pipeline or in the instruction prefetch buffer.