Advanced POC model-based Java instruction folding mechanism

Abstract

Ever since Java was introduced world wide, the execution performance has always been a problem. As one of the solutions, a bytecode instruction folding process for Java processors was developed in a PicoJava model and a Producer, Operator and Consumer (POC) model, but it could not handle certain types of instruction sequences. In this paper, a new instruction folding scheme based on a new, advanced POC model is proposed and demonstrates improvement in bytecode execution. The proposed POC model is able to detect and fold all possible instruction sequence types dynamically in hardware, including a sequence that is separated by other bytecode instructions. SPEC JMV98 benchmark results show that the proposed POC model-based folder can save more than 90% of folding operations. In addition, a design of the proposed POC model-based folding process in hardware is much smaller and more efficient than traditional folding mechanisms.