SHRINK: Reducing the ISA complexity via instruction recycling
SHRINK: Reducing the ISA complexity via instruction recycling
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SHRINK：通过指令回收降低 ISA 复杂性
DOI：
10.1145/2749469.2750391
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发表时间：
2015
期刊：
影响因子：
--
通讯作者：
R. Azevedo
中科院分区：
文献类型：
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作者：
B. Lopes;R. Auler;Luiz E. Ramos;E. Borin;R. Azevedo
微处理器制造商通常在现代处理器中保留旧的指令集，以确保与遗留软件的向后兼容性。对伊萨的更新扩展的引入增加了微处理器前端的设计复杂性，加剧了宝贵的片上资源（例如，硅面积和能量），并且需要更多的努力来进行硬件验证和调试。我们分析了1995年至2012年间部署的几个x86应用程序和操作系统，发现随着时间的推移，许多指令停止使用，超过500条指令从未在这些应用程序中使用过。我们还调查的影响，包括这些未使用的指令的x86解码器的设计，并提出收缩，一种机制，以删除旧的指令，而不破坏向后兼容的遗留代码。SHRINK允许我们从x86伊萨中删除40%的指令，并将指令解码器的关键路径、面积和功耗分别平均提高23%、48%和49%。
Microprocessor manufacturers typically keep old instruction sets in modern processors to ensure backward compatibility with legacy software. The introduction of newer extensions to the ISA increases the design complexity of microprocessor front-ends, exacerbates the consumption of precious on-chip resources (e.g., silicon area and energy), and demands more efforts for hardware verification and debugging. We analyzed several x86 applications and operating systems deployed between 1995 and 2012 and observed that many instructions stop being used over time, and more than 500 instructions were never used in these applications. We also investigate the impact of including these unused instructions in the design of the x86 decoders and propose SHRINK, a mechanism to remove old instructions without breaking backward compatibility with legacy code. SHRINK allows us to remove 40% of the instructions from the x86 ISA and improve the critical path, area, and power consumption of the instruction decoder, respectively, by 23%, 48%, and 49%, on average.