Integrating operation scheduling and binding for functional unit power-gating in high-level synthesis

Power-gating-aware design has been an active area of research in the last decade, aiming at reducing power dissipation while meeting a desired system throughput. In this study, an algorithm integrating both scheduling and binding processes is developed with the functional unit (FU) power-gating technique, to achieve maximum leakage energy reduction under both performance and resource constraints. Firstly, the possible leakage energy reductions of all idle intervals are analyzed by evaluating the operation mobilities. Secondly, a split network indicating the leakage energy reduction in each idle interval is constructed, and a min-cost flow-based algorithm is conducted to this network to evaluate the total leakage energy saving from power-gating FUs; operations are scheduled to the clock cycles and bound to FUs with a maximization of leakage energy saving. Finally, proper FUs are clustered under power domain constraints to maximize the leakage energy saving while reducing the area and wirelength penalties for fine grain power-gating. Experimental results show the effectiveness of our proposed algorithms in saving leakage energy.