Incremental Placement Algorithm for Wirelength and Routability Optimization

Typical placement objectives involve reducing net-cut cost or minimizing wirelength. Congestion minimization is least studied, however, it models routability most accurately. A new incremental placement algorithm C-ECOP is presented for standard cell layout. The algorithm first estimates the routing congestion through a new route model. Then it minimizes the congestion during inserting and moving cells through force driven. At the same time, it reduces the wirelength. Test cases from industry show that the algorithm can avoid causing congestion during adjusting the placement and preserve the performance of the initial placement with good quality and high speed.