Pipeline stage unification: a low-energy consumption technique for future mobile processors

Recent mobile processors are required to exhibit both low-energy consumption and high performance. To satisfy these requirements, dynamic voltage scaling (DVS) is currently employed. However, its effectiveness will be limited in the future because of shrinking the variable supply voltage range. As an alternative, we previously proposed pipeline stage unification (PSU), which unifies multiple pipeline stages without reducing the supply voltage at a power-saving mode. This paper compares effectiveness of PSU to DVS in current and future process generations. Our evaluation results show PSU will reduce energy consumption by 27-34% more than DVS after about 10 years.