The JAFARDD processor: a Java architecture based on a folding algorithm, with reservation stations, dynamic translation, and dual processing

Abstract

This paper presents the JAFARDD (a Java Architecture based on a Folding Algorithm, with Reservation stations, Dynamic translation, and Dual processing) processor. JAFARDD dynamically translates Java stack-dependent bytecodes to RISC-style stack-independent instructions to facilitate the use of a general-purpose RISC core. JAFARDD enables the exploitation of instruction level parallelism among the translated instructions by the use of bytecode folding coupled with Tomasulo's algorithm. We detail the JAFARDD architecture and the global architecture design principles observed while designing each pipeline module. We also illustrate the flow of the Java bytecodes through each of the processing phases. Benchmarking of JAFARDD using SPECjvm98 has shown a performance improvement between 1.10 and 2.25.