E cient Network Flow Based Min-Cut Balanced Partitioning

We consider the problem of bipartitioning a circuit into two balanced components that minimizes the number of crossing nets. Previously, the Kernighan and Lin type (K&L) heuristics, the simulated annealing approach, and the spectral method were given to solve the problem. However, network ow techniques were overlooked as a viable approach to min-cut balanced bipartition due to its high complexity. In this paper we propose a balanced bipartition heuristic based on repeated maxow min-cut techniques, and give an efcient implementation that has the same asymptotic time complexity as that of one maxow computation. We implemented our heuristic algorithm in a package called FBB. The experimental results demonstrate that FBB outperforms the K&L heuristics and the spectral method in terms of the number of crossing nets, and the e cient implementation makes it possible to partition large circuit instances with reasonable runtime. For example, the average elapsed time for bipartitioning a circuit S35932 of almost 20K gates is less than 20 minutes.