以電路重新配置改進全域繞線器的可繞度和線長

Abstract

在實體設計中，配置器扮演的相當重要的角色。它決定了電路線長的最低界線，且配置結果會對全域繞線器的可繞度和線長有很大的影響。為了拉近配置器和繞線器的關係，我們結合配置器和繞線器來幫助我們配置器可以更準確的估計繞線器的線長。這個作品提出兩個階段來改善繞線器的可繞度和減少繞線器的線長，分別為:減少線長和減少擁擠。在減少線長的階段中，我們提出了三個方法：減少線長的移動，加強化的區域重新安排，和以雙族匹配方法重新佈置元件。在減少擁擠的階段中，我們提出了兩個方法:元件排列和避免擁擠的移動來。實驗結果說明了我們用IBMv2的測試檔改善了兩個配置器:Dragon和mPL-R的線長分別改善了4.2百分比和2.3百分比。另外，我們改善了兩個配置器預先繞線的滿載，分別改善了6.4百分比和6.6百分比。

Placement plays an important role in physical design. It determines the lower bound of circuit wirelength and its result significantly influences circuit routability. In order to close the gap between placement and routing, we integrate global routing and placement to help our placer perform more accurate estimation of routed wirelength. This work presents two stages to improve routability and wirelength of global routing including wirelength minimization stage and congestion reduction stage. In wirelength minimization stage, we present threes methods, namely wirelength-reduced cell shifting, enhanced local re-ordering, and cell rearrangement by bipartite matching. In congestion reduction stage, we present cell sorting based congestion reduction and congestion-avoided cell shifting. Experimental results demonstrate that our placer improves total wirelength by 4.2% and 2.3% as compared to Dragon and mPL-R on IBMv2 benchmarks. Furthermore, our placer improves overflow of pre-routing by 6.4% and 6.6% as compared to Dragon and mPL-R.