基于SimpleScalar的龙芯CPU模拟器Sim-Godson

Sim-Godson:A Godson Processor Simulator Based on SimpleScalar

现代高性能通用处理器的设计越来越复杂,模拟器在处理器设计中所起的作用越来越大.龙芯2号是中国科学院计算技术研究所研制的高性能通用处理器.最早开发的龙芯2号的模拟器ICT-Godson是信号级模拟器,它模拟了处理器的所有细节,十分准确,但速度和灵活性有较大限制.文章基于SimpleScalar工具集,设计并实现了龙芯2号的模拟器Sim-Godson.Sim-Godson具有高速度和高灵活性的优点,且准确性也很高.在3.0GHz的Pentium4微机上,Sim-Godson速度约为500K指令/s.大部份测试程序在Sim-Godson上的IPC(Instruction PerCycle)与ICT-Godson相差不到5%,达到了很高的准确性.Sim-Godson在龙芯2号的性能分析工作中发挥了重要作用.

As the increase in complexity of modern processor design, simulator is becoming more and more important in processor design. Godson-2 is a high performance general purpose processor developed by the Institute of Computing Technology, Chinese Academy of Sciences. ICTGodson, the initial simulator of Godson-2, is a signal level simulator, which simulates all hardware details of Godson-2 and is very accurate. But the speed of ICT-Godson is not high enough and the flexibility is not good. Based on SimpleScalar tool sets, Sire-Godson, one processor sireulator of Godson-2, is son has high speed and designed and implemented. Comparing with the ICT-Godson, Sire-Godhigh flexibility and the accuracy is also very good. On PC of Pentium4 3.0GHz, the speed of Sim-Godson is about 500K instructions per second. IPC（Instruction Per Cycle） difference between Sim-Godson and ICT-Godson is less than 5 percent for the most applications. Sim-Godson plays an important role in the performance analysis of God-son-2.