A power-aware branch predictor by accessing the btb selectively 一个有选择性访问btb的功耗敏感型分枝预测器
This paper proposes a power-aware branch predictor, which is based on the gshare predictor, by accessing the btb branch target buffer selectively 本文提出的是一个功耗敏感型的分枝预测器,它是基于gshare的一个有选择性访问btb的预测器。
Microarchitects should consider power consumption, together with accuracy, when designing a branch predictor, especially in embedded processors 在设计分枝预测器时,尤其是在设计嵌入式处理器中的分枝预测器时,微电子设计师应该考虑功耗及精度。
The proposed branch predictor reduces the power consumption with little hardware overhead, not incurring additional delay and never harming prediction accuracy 本文提出的分枝预测器能够降低功耗,硬件开销很小,不会招致额外的延迟而且决不会影响预测精度。
In the proposed branch predictor, if the previous instruction was not a branch and the prediction from the pht is untaken, the btb is not accessed to reduce power consumption 在本文提出的分枝预测器中,如果前一条指令不是一个分枝且pht的预测尚未执行,那么btb就不被访问以降低功耗。
Dongrui fan, hongbo yang, guangrong gao et al ., “ evaluation and choice of various branch predictors for low-power embedded processor ”, journal of computer science & technology, vol . 18 no . 6, nov . 2003 范东睿,“不同层面上处理器功耗评估工具的对比研究”,第八届计算机科学与技术学术研讨会,大连,2004年7月。
Tpbtp mechanism evaluates branch target from a direct branch in advance, so to make up the insufficiency of branch predictor and branch target buffer, and constructs instruction traces before program execution tpbtp机制从直接分支指令中提取目标地址,弥补分支预测和分支目标缓存的不足,加速指令读取,实现trace预构。
Then, the work researches multithread processor architecture based on the armp . this dissertation focused on the branch predictor of high performance processor and fetch unit of selective execution of multithread architecture 接着,本文以armp为基础深入了解国内外目前最先进的多线程处理器系统结构研究工作,明确了该领域研究的发展方向和研究难点。
To enable the selective access to the btb, the pht pattern history table in the proposed branch predictor is accessed one cycle earlier than the traditional pht if the program is executed sequentially without branch instructions 如果程序是在无分枝指令情况下顺序执行,为了使能对btb有选择性的访问,本文提出的分枝预测器中的pht要比传统的pht提早一个周期访问。
Several other implementation issues, including instruction window size, issue width and branch predictor are also addressed and simulated . simulation results indicate that data value predictors act differently under different configurations 值预测是一种预测机制,它基于指令已产生结果的特征预测指令未来将要产生结果,从而使后续相关指令得以利用预测值前瞻执行。