Register files (RF) represent a substantipl portion of the energy budget in modem processors, and are growing rapidly with the trend towards wider instruction issue. The actual access energy costs depend greatly on the register file circuitry used. This paper compares various RF circuitry techniques for their energy ejl ficiencies, as a function of architectural parameters such as the number of registers and the number of ports. The Port Priority Selection technique was found to be the most energy eficient. The dependence of register file access energy upon technology scaling is also studied. Howevel; as this paper shows, it appears that none of these will be enough to prevent centralized register jiles from becoming the dominant power component of next-generation superscalar computers, and alternative methods for inter-instructio ' 1 communication need to be developed. Split register file architecture is analyzed as a possible alternative.
Modified register file organizations, such as REF , concentrate on reducing the number of ports in a register file to reduce energy.
The energy complexity of register files
Proceedings. 1998 International Symposium on Low Power Electronics and Design (IEEE Cat. No.98TH8379)
Proceedings. 1998 International Symposium on Low Power Electronics and Design (IEEE Cat. No.98TH8379)
Computer Science