Boosting: Min-Cut Placement with Improved Signal Delay

In this work we improve top-down min-cut placers in the context of timing closure. Using the concept of boosting factors, we adjust net weights according to net spans, so as to reduce the quadratic wirelength. Our method is generic and does not involve any timing analysis during or prior to placement. In essence, we skew the netlength distribution produced by a mincut placer so as to decrease the number of long nets, with minimal impact on the overall wirelength. Empirically this approach does not significantly affect runtime, but reduces the worst negative slack and total negative slack of industrial benchmarks by up to 70% compared to Capo [5] and a leading industrial placer.

• Type: Conference
• Year: 2004
• Where: DATE
• Authors: Andrew B. Kahng, Igor L. Markov, Sherief Reda
• Keywords: DATE 2004, Hardware, Negative Slack, Top-down Min-cut Placers, Worst Negative Slack