Nop Compression Scheme for High Speed DSPs Based on VLIW Architecture

VLIW (Very Long Instruction Word) is one of the most popular architectures in embedded systems because it has features of low power consumption and low hardware cost. Due to the nature of VLIW architecture such as bundled instructions and large register files, VLIW processors are running with large size of instruction codes in relatively low clock frequency. However compact instruction size and high clock frequency are the most important requirements of modern embedded consumer electronics. In this paper we propose a novel instruction compression scheme to solve the addressed problem. The experiment shows that the proposed scheme can reduce instruction size by 23% and improve clock frequency by 25% in average comparing with conventional compression schemes.