PROCESSOR WITH VARIABLE PRE-FETCH THRESHOLD

摘要

A method and apparatus for controlling pre-fetching in a processor. A processor includes an execution pipeline and an instruction pre-fetch unit. The execution pipeline is configured to execute instructions. The instruction pre-fetch unit is coupled to the execution pipeline. The instruction pre-fetch unit includes instruction storage to store pre-fetched instructions, and pre-fetch control logic. The pre-fetch control logic is configured to fetch instructions from memory and store the fetched instructions in the instruction storage. The pre-fetch control logic is also configured to provide instructions stored in the instruction storage to the execution pipeline for execution. The pre-fetch control logic is further configured set a maximum number of instruction words to be pre-fetched for execution subsequent to execution of an instruction currently being executed in the instruction pipeline. The maximum number is based on a value contained in a pre-fetch threshold field of an instruction executed in the execution pipeline.

主权项

1. A processor, comprising:
an execution pipeline configured to execute instructions; an instruction pre-fetch unit coupled to the execution pipeline, instruction pre-fetch unit comprising:
instruction storage to store pre-fetched instructions; andpre-fetch control logic configured to:
fetch instructions from memory and store the fetched instructions in the instruction storage;provide instructions stored in the instruction storage to the execution pipeline for execution; andselectably set a maximum number of instruction words to be pre-fetched for execution subsequent to execution of an instruction currently being executed in the instruction pipeline, the maximum number based on a value contained in a pre-fetch threshold field of an instruction executed in the execution pipeline.