Large-Capacity and High-Speed Instruction Cache Based on Divide-by-2 Memory Banks  

作　　者：Qing-Qing Li Zhi-Guo Yu Yi Sun Jing-He Wei Xiao-Feng Gu 

机构地区：[1]with the Engineering Research Center of IoT Technology Applications(Ministry of Education),Jiangnan University,Wuxi 214122 [2]with the No.58 Research Institute,China Electronics Technology Group Corporation,Wuxi 214035

出　　处：《Journal of Electronic Science and Technology》2021年第4期335-349,共15页电子科技学刊（英文版）

基　　金：the Postgraduate Research Innovation Program of Jiangsu Province under Grant No.KYCX20_1936;the Fundamental Research Funds for the Central Universities under Grant No.JUSRP51510;the Key Research and Development Program of Jiangsu under Grant No.BE2019003-2.

摘　　要：An increase in the cache capacity is usually accompanied by a decrease in access speed.To balance the capacity and performance of caches,this paper proposes an instruction cache(ICache)architecture based on divide-by-2 memory banks(D2MB-ICache).The control circuit and memory banks of D2MB-ICache work at the central processing unit(CPU)frequency and the divide-by-2 CPU frequency,respectively,so that the capacity of D2MB-ICache can be expanded without lowering its frequency.For sequential access,D2MB-ICache can output the required instruction from memory banks per CPU cycle by dividing the memory banks with a partition mechanism and employing an inversed clock technique.For non-sequential access,D2MB-ICache will fetch certain jump instructions one or two more times,so that it can catch the jump of the request address in time and send the correct instruction to the pipeline.Experimental results show that,compared with conventional ICache,D2MB-ICaches with the same and double capacities show a maximum frequency increase by an average of 14.6%and 6.8%,and a performance improvement by an average of 10.3%and 3.8%,respectively.Moreover,energy efficiency of 64-kB D2MB-ICache is improved by 24.3%.

关 键 词：Cache capacity expansion divide-by-2 frequency instruction cache(ICache) inversed clock. 

分 类 号：TP333[自动化与计算机技术—计算机系统结构]