Enhancing multimedia processing by wave-pipelining integer units and floating point units in whole

Abstract

A ubiquitous processor, HCgorilla followed Java CPU for multimedia processing and was built in RNG (random number generators) for cipher processing. Then, HCgorilla had an execution stage composed of several units for those sophisticated processing. Since the execution stage kept physical separation, each function took different latency. This required instruction scheduling similarly to regular super scalar processors. We describe, in this paper, the improvement of HCgorilla to solve this issue. Specifically, the execution stage composed of arithmetic units is wave-pipelined in whole. This completely merges the parallel structure without physical separation. The waved multifunctional execution unit is effective to realize wide-range dynamic ILP (instruction level parallelism) at a rate higher than regular superscalar processors.