AN EFFICIENT PARALLEL CRITICAL PATH ALGORITHM

The problem of identifying one of the longest sensitizable paths in a circuit is called a critical path problem. Several critical path algor ithms have been proposed in the last few years. However, due to the lo ng computation time required to produce accurate results, these algori thms may not be able to generate any result for large designs with man y long false paths unless the accuracy of the results is compromised. Parallel processing seems to be an appropriate way to speed up the req uired computation. In this paper, we study the parallel algorithms for critical path problem. We first present a sensitization criterion. Ba sed on this sensitization criterion an algorithm called DT-algorithm, which is a variation of the D-algorithm with stable Time range of sign als also taken into consideration, is developed. The DT-algorithm is e specially suitable and can be used to determine the sensitizability of a given path in a parallel processing environment. We also presented an implementation of parallel DT-algorithm that can be executed on a s hared memory multiprocessor. The experimental results show that a reas onable speed-up can be obtained.