Unicore架构下的Dalvik虚拟机优化

Optimization of Dalvik virtual machine based on Unicore architecture

基于Unicore架构,对Dalvik虚拟机进行了移植优化.通过分析Unicore架构下应用程序二进制接口与Dalvik虚拟机的平台相关性,设计实现了jniArgInfo变量字段的布局以及与Dalvik虚拟机平台相关的本地方法调用桥.在设计完成Unicore架构下的快速型解释器入口函数、别名寄存器、汇编宏定义以及汇编版本快速型解释器架构等组件的基础上,结合虚拟机快速型解释器的混合实现机制对Dalvik虚拟机进行了优化,并对优化后Dalvik虚拟机的兼容性、功能、性能进行了测试验证.实验结果表明,优化后的Dalvik虚拟机符合Android系统规范,虚拟机核心部件及Dalvik解释器性能稳定,与优化前相比,系统每秒执行的字节码数目提升达147%.与同类平台的对比测试结果验证了Dalvik虚拟机性能提升的合理性.

Based on the Unicore architecture, the Dalvik VM （virtual machine）is transplanted and optimized. First, the relationships between the application binary interfaces of Unicore and Dalvik VM platform are analyzed, and the layout of jniArglnfo＇s variable field and JNICallbridge （Java native interface Callbridge） which relates with the Dalvik VM are implemented. After several components of the fast interpreter, which includes the entry functions, alias registers, key assembly macro definitions and architecture in assembly version based on Unicore, are implemented, the Dalvik VM is optimized with the mixed mechanism advantage of the fast interpreter. The compatibility, function and performance of the optimized Dalvik VM are tested and verified. The experimental results show that, compared with the system before optimization, the Dalvik VM based on the Unicore architec- ture fully complies with the Android system. The core partitions and the whole Dalvik interpreter are robust and run steadily. The number of executed bytecode is speedup by 147% per second, and the rationality of the performance gains are verified by comparing with other similar platforms.