基于SimpleScalar的龙芯CPU模拟器Sim-Godson

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 Per Cycle)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.

Sim-Godson: A Godson Processor Simulator Based on SimpleScalar

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.ICT-Godson,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,Sim-Godson,one processor simulator of Godson-2,is designed and implemented.Comparing with the ICT-Godson,Sim-Godson has high speed and high 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.