MICROPROCESSOR WITH MULTI-STEP AHEAD BRANCH PREDICTOR

摘要

A microprocessor is shown, in which a branch predictor and an instruction cache are decoupled by a fetch-target queue (FTQ). The branch predictor performs branch prediction for N instruction addresses in parallel in the same cycle, wherein N is an integer greater than 1. In the current cycle, the branch predictor finishes branch prediction for N instruction addresses in parallel and, among the N instruction addresses with finished branch prediction, those that are not bypassed and do not overlap previously-predicted instruction addresses are pushed into the fetch-target queue, to be read out later as an instruction-fetching address for the instruction cache. The previously-predicted instruction addresses are pushed into the fetch-target queue in a previous cycle.