基于备份缓冲区的精确中断研究与实现

微处理器的深度流水线、乱序执行等技术会导致指令的顺序模型与乱序执行之间产生冲突,如何实现精确中断是其中的关键问题之一。针对现有精确中断实现方法的不足,提出了一种采用备份缓冲区保存流水线现场的精确中断实现方法,可以显著提高中断响应的效率。论文首先详细分析了中断,然后着重讨论了备份缓冲区实现精确中断的现场保存机制和备份缓冲区的结构,最后介绍了该方法在西北工业大学自主设计的“龙腾R2”微处理器上的实现。“龙腾R2”微处理器上的实验结果表明,与冲刷流水线实现精确中断的方法相比,采用该方法中断响应时间减少了67%,中断返回时间减少了56%。

New precise interrupt mechanism based on backup-buffer

The technologies of deep stage pipeline and out-of-order execution in microprocessor induce the hazard between sequential model and out-of-order execution,so the key problem is how to implement precise interrupt.To the deficiency of the existing method,this paper has proposed a method,which use backup-buffer to save the status of pipeline,can improve the efficiency of interrupt response.Section one and two analyze traditional implementation of precise interrupt.Section three discusses the mechanism of saving status by backup-buffer and the architecture of backup-buffer emphatically.Section four presents the implementation on the NWPU AMEC's full copyright microprocessor "LongtiumR R2".Experiments show that this new method reduces the time of interrupts response 67%,the time of return from interrupts by 56%.