Method and system for instruction branch prediction

Abstract

The invention discloses an instruction branch prediction method and system. After the current instruction is executed, a preset number of instructions to be executed in the sequential execution direction are obtained and cached, and it is judged whether the first cached instruction is a jump instruction type. If If it is, calculate the jump target address and cache the target jump instruction. When the jump condition is met, it directly reads the cache of the target jump instruction to execute the jump instruction. If the jump condition cannot be met, it directly reads the cache for sequential execution. The second instruction in the direction, when the jump instruction is executed, no matter whether the jump condition is met or not, the subsequent instructions to be executed have been obtained and can be directly read from the cache for execution, through jump instruction prediction, instruction prefetch, instruction The mode of cache and direct read cache realizes bidirectional instruction branch prediction, solves the processor pipeline stall caused by jump instructions, and eliminates the reduction in processor execution efficiency caused by inserting branch delay gaps.

Description

technical field [0001] The invention relates to the field of processors, in particular to an instruction branch prediction method and system. Background technique [0002] When a processor with pipeline technology processes a branch instruction, depending on the true / false of the judgment condition, a jump may occur, which will interrupt the processing of the instruction in the pipeline, because the processor cannot determine the next step of the instruction. instructions until the branch is executed. The longer the pipeline, the longer the processor waits, because it must wait for the branch instruction to be processed before it can determine the next instruction to enter the pipeline. [0003] At present, small-scale processors do not have instruction branch prediction function or only have unidirectional static branch prediction function. If there is a jump instruction in a non-sequential execution direction, the processor pipeline will stall, which will lead to the inse...

AI Technical Summary

Problems solved by technology

[0003] At present, small-scale processors do not have instruction branch prediction function or only have unidirectional static branch prediction function. If there is a jump instruction in a non-sequential execution direction, the processor pipeline will stall, which will lead to the insertion of branch delay gaps and reduce the execution efficiency of the processor.

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