Timing model reduction for hierarchical timing analysis.

In this paper, we propose a timing model reduction algorithm for hierarchical timing analysis based on a bicliquestar replacement technique. In hierarchical timing analysis, each functional block is characterized into an abstract timing model. The complexity of analysis is linear to the number of edges in the abstract timing model for timing propagation. We propose a biclique-star replacement technique to minimize the number of edges in the timing model. The experiments on industry test cases show that by allowing acceptable errors, the proposed algorithm can largely reduce the number of edges in the timing model.