Device and method for realizing indirect branch prediction of modern processor

Abstract

The invention discloses a device and a method for realizing the indirect branch prediction of a modern processor. The device comprises a direction predictor, a group-path pointer register and a branch target buffer, wherein the direction predictor selects a first access index and a second access index of a mode historical record while predicting an indirect branch instruction direction, and generates and outputs a corresponding group-path pointer through the mode historical record; the group-path pointer register stores the group-path pointer output by the mode historical record; the branch target buffer establishes subblocks and allocation items; each subblock allocates a destination address item indexed by the group-path pointer to each indirect branch instruction; and each allocation item is used for recording the using condition of the destination address item of each indirect branch instruction. By the device and the method, a prediction effect similar to the effect of direct address prediction can be achieved on the basis that the support of a high-capacity storage structure is not needed, so the energy efficiency of the processor can be improved.

Description

technical field [0001] The invention relates to the design of a modern microprocessor and its application system, in particular to a device and method for realizing the prediction of an indirect transfer instruction of a modern processor. Background technique [0002] Modern high-performance processors utilize branch instruction prediction techniques to exploit instruction-level parallelism to increase processor performance. Previous studies mainly focused on developing high-accuracy direct branch instruction prediction techniques, but for indirect branch instruction prediction, it is usually difficult to achieve high accuracy. In recent years, with the wide application of object-oriented language programs, there are more occasions where indirect transfer instructions are used. This type of instruction is usually used to implement common data structures such as virtual function pointers, function pointers, and Switch-Case statements. In addition, a dedicated indirect branc...

AI Technical Summary

Problems solved by technology

Techniques such as this use dedicated components are faster to predict, but their additional memory cell requirements take up real estate on the chip and generate a lot of power

The VPC technology that focuses on the use of existing branch prediction components can achieve higher prediction accuracy, but this kind of prediction that requires multiple cycles to complete an indirect transfer will hinder the further improvement of processor performance on the one hand, and on the other hand Incurs more energy overhead, resulting in less energy-efficient processors

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