Asynchronous Control Network Optimization Using Fast Minimum-Cycle-Time Analysis

This paper proposes two methods for optimizing the control networks of asynchronous pipelines. The first uses a branch-and-bound algorithm to search for the optimum mix of the handshake components of different degrees of concurrence that provides the best throughput while minimizing asynchronous control overheads. The second method is a clustering technique that iteratively fuses two handshake components that share input channel sources or output channel destinations into a single component while preserving the behavior and satisfying the performance constraint of the asynchronous pipeline. We also propose a fast algorithm for iterative minimum-cycle-time analysis. The novelty of the proposed algorithm is that it takes advantage of the fact that only small modifications are made to the control network during each optimization iteration. When applied to nontrivial designs, the proposed optimization methods provided significant reductions in transistor count and energy dissipation in the designs' asynchronous control networks while satisfying the throughput constraints.