Functional cores: Trade a little performance to save power

Recent process scaling in CMOS technology increases transistor counts while there is limited power budget on chip. As power is more expensive than area, trading area to save power is recommended. In this regime, specialized and energy-efficient processing engines can increase the energy efficiency by reducing energy per computation. To achieve this goal, we introduce specialized hardware accelerators namely functional cores. Functional cores are the hardware realization of a function in software program. Considering energy consumption and performance, these cores perform the functions more efficiently compared to their execution on a general purpose processor. Since decreasing power consumption is more important than execution time in several applications, we exploit hardware accelerators for power reduction rather than performance improvement. To this end, we use high level synthesis for automatic generation of functional cores in ASIC domain. Experimental results obtained on a set of benchmark programs reveal that depending on function size, 32% to 75% reduction in power consumption is observed.