Instruction Cache Leakage Reduction by Changing Register Operands and Using Asymmetric SRAM Cells
Share of leakage in cache memories is increasing with technology scaling. Studies show that most stored bits in instruction caches are zero, and hence, asymmetric SRAM cells which dissipate less leakage when storing 0, effectively reduce leakage with negligible performance penalty. The authors show that by carefully choosing register operands of instructions, it is possible to further increase the number of 0 bits, and hence, increase leakage savings in instruction cache. This compiler technique is performed off-line and introduces absolutely no delay penalty since processor registers are all the same.