Method for detecting branch prediction and processor

Abstract

The embodiment of the invention provides a method for detecting branch prediction and a processor, and the method comprises the steps: predicting a branch prediction result according to first branch information stored in a branch prediction buffer, the branch prediction result at least comprising a current fetch address; at the stage of fetching fingers from a cache according to the current fingerfetching address, if second branch information matched with the current finger fetching address is found in a cached instruction cache block, reading the matched second branch information, wherein second branch information is stored in the cached instruction cache block; and detecting whether the branch prediction is correct or not according to the matched second branch information. The embodiment of the invention can provide possibility for correcting the branch prediction error in advance in the fetch stage when the branch prediction error is found in the fetch stage based on the detectionresult whether the branch prediction is correct or not, so that the pipeline resource consumption and delay caused by the branch prediction error can be greatly reduced.

Description

technical field [0001] Embodiments of the present invention relate to the technical field of processors, and in particular to a method for detecting branch predictions and a processor. Background technique [0002] Modern processors generally use pipeline technology to process instructions in parallel to speed up instruction processing efficiency; when processing branch instructions, in order to avoid waiting for the execution result of the branch instruction to determine the branch direction, most modern processors use branch prediction (Branch Prediction) technology. [0003] The branch prediction can predict the branch direction and other results of the branch instruction, so as to push the processor to fetch the next instruction, avoiding the pipeline delay caused by waiting for the execution result of the branch instruction. However, branch prediction also has the possibility of misprediction. When a branch prediction error occurs, it is necessary to clear the wrongly ...

AI Technical Summary

Problems solved by technology

However, branch prediction also has the possibility of misprediction. When a branch prediction error occurs, it is necessary to clear the wrongly fetched instruction caused by the branch prediction error in the pipeline to correct the branch prediction error, which consumes a lot of pipeline resources and expands the pipeline delay.

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