Generic Global Placement and Floorplanning

Abstract

We present a new force-directed method for global placement. Besides the well-known wire length dependent forces we use additional forces to reduce cell overlaps and to consider the placement area. Compared to existing approaches, the main advantage is that the algorithm provides increased flexibility and enables a variety of demanding applications. Our algorithm is capable of addressing the problems of global placement, floorplanning, timing minimization and interaction to logic synthesis. Among the considered objective functions are area, timing, congestion, and heat distribution. The iterative nature of the algorithm assures that timing requirements are precisely met. While showing similar CPU time requirements it outperforms Gordian by an average of 6 percent and TimberWolf by an average of 8 percent in wire length and yields significantly better timing results.

Proc. of the 35th Annual Design Automation Conference, pp. 269-274, June 1998.