一种基于敏感度的时延驱动快速布局算法

A Sensitivity-Based Timing-Driven Fast Placement Algorithm

本文提出了一种基于敏感度的时延驱动的快速布局算法.该算法在解方程和单元扩散这两个阶段同时优化关键线网时延.其中基于敏感度的线网权重模型用于解方程阶段,基于关键路径的启发式单元优化算法用于单元扩散阶段.静态时延分析工具Astro分析结果表明:与FastPlace相比,最小负松弛量(worst negative slack)平均提高了25.82%,负松弛量总和(total negative slack)平均提高了20.53%,同时总线长仅平均增加3.14%且运行时间没有明显增加.

This paper presents a sensitivity-based timing-driven fast placement algorithm, which considers the critical net de- lay optimization in both the equation solving stage and the cell shifting stage.A sensitivity net-based weighting model is used in e- quation solving stage and a heuristic critical path based algorithm is used in cell shifting stage. Experimental results show that worst negative slack （WNS） aald total negative slack （TNS） are improved by 25.82 % and 20.53 % respectively using the static timing analysis tool Aslro.Meanwhile, average wire length is only increased by 3.14% and the runfime is not increased significantly in comparison with FastPlace.