Exploiting Narrow Bitwidth Operations for Low Power Embedded Software Optimization
Seiichiro Yamaguchi, 誠一朗 山口, Masanori Muroyama, 真徳 室山, Tohru Ishihara, 亨 石原, Hiroto Yasuura, 寛人 安浦 · QIR (Kyushu University Institutional Repository) (Kyushu University) · 2006
This paper proposes a low power software optimization technique for processor-based embedded systems. A basic idea is to reduce switching activities in sign extension bits of instruction operands through shifting the operands. Our technique, called shift operation insertion technique in this paper, consists of following three steps: 1) shift operands from LSB side toward MSB side by optimal shift amount, 2) execute instructions with the shifted operands, and 3) shift back computational results to original positions. Experimental results show about 10.7% energy reduction of datapath, and about 5.5% energy reduction of overall processor.