Instruction buffering for nested loops in low power design

Loop buffering techniques have been proposed for reducing power consumption. Although such schemes are effective in reducing power, they work for the innermost loop only. In this paper, we propose a stack-based controller which can deal with nested-loops of all styles, and also the if-then-else construct in a loop. Our experiments, using the Wattch power estimator (D. Brooks et al, Int. Symp. Comp. Architecture, pp. 83-94, 2000), show that the power consumption reduction of our technique at fetch and decode stages is up to 40% when compared to that of previously proposed techniques with the innermost loop only.