WEAVER: A Knowledge-Based Routing Expert

In this paper we describe WEAVER, a channel/switch-box knowledge-based routing program. WEAVER considers all the important routing metrics such as 100% routability, minimum routing area, minimum wire length, and minimum number of vias simultaneously. It allows pre-routed nets, and user interaction throughout the entire routing process. It also relaxes unnecessary constraint of assigning different layers to different directions, the constraint imposed by all of the current channel and switch-box routers. WEAVER is a grid-based router that utilizes two interconnection layers and can be easily expanded to route any shape routing area such as ´T´ or ´+´. Implemented in OPS5, a production system language, WEAVER routinely produces routings requiring less area than routers that focus on a single routing metric.