基于musl libc库的RVV优化  

RVV Optimization Based on musl libc Library

作　　者：张飞 于佳耕[1] 邢明杰 武延军[1] ZHANG Fei;YU Jia-Geng;XING Ming-Jie;WU Yan-Jun(Institute of Software,Chinese Academy of Sciences,Beijing 100190,China;Intelligent Software Research Center,Nanjing Institute of Software Technology,Nanjing 211100,China)

机构地区：[1]中国科学院软件研究所,北京100190 [2]中科南京软件技术研究院智能软件研究中心,南京211100

出　　处：《计算机系统应用》2023年第11期29-35,共7页Computer Systems & Applications

摘　　要：musl libc是一个轻量级的标准C库,其代码库小巧,提供了全面的POSIX接口支持,具有高度可移植性并支持多种架构和操作系统,被广泛用于嵌入式系统、网络服务器、容器等领域.RISC-V指令集作为一种开源的指令集,目前发布了相对稳定的SIMD指令集,RISC-V生态软件环境也迎来了新的优化热潮,但是对于musl libc库RVV扩展优化还是一片空白.本文立足于musl libc基础库和RISC-V RVV扩展指令集的协同研究点,提出了兼容基础指令集和向量扩展指令集的实现方案,利用向量扩展指令集优化了常见的C库函数strlen和memset,并在gem5模拟器上进行了对比分析,实验结果表明,相较于C语言实现,在性能方面,利用RVV优化的strlen函数平均提升83%–703%,memset函数平均提升85%–334%.As a lightweight standard C library,musl libc features a small code base providing comprehensive POSIX interface support,and high portability and support for various architectures and operating systems.It is widely employed in embedded systems,Web servers,containers,and other fields.RISC-V instruction set is an open source instruction set that has released the relatively stable SIMD instruction set at present.Meanwhile,the RISC-V ecological software environment has ushered in a new optimization boom,but the RVV extension optimization of the musl libc library is still a research gap.Based on the collaborative research of the musl libc basic library and RISC-V RVV extended instruction set,this study proposes an implementation scheme compatible with the basic instruction set and vector extended instruction set.The common C library functions strlen and memset are optimized by the vector extended instruction set,and comparative analysis is carried out on gem5 simulator.The experimental results show that compared with the implementation of C language,the performance of strlen function optimized by RVV is improved by 83%–703%on average,and that of memset function is improved by 85%–334%on average.

关 键 词：musl libc RISC-V 基础指令集 RVV扩展优化 

分 类 号：TP332[自动化与计算机技术—计算机系统结构]