Table of Contents
VLSI Design
Volume 4, Issue 1, Pages 11-16

An O(NlogN) Algorithm for Region Definition Using Channels/Switchboxes and Ordering Assignment

Department of Computer and Information Science, National Chiao Tung University, Hsinchu, Taiwan

Received 25 September 1993; Revised 20 August 1994

Copyright © 1996 Hindawi Publishing Corporation. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


For a building block placement, the routing space can be further partitioned into channels and switchboxes. In general, the definition of switchboxes releases the cyclic channel precedence constraints and further yields a safe routing ordering process. However, switchbox routing is more difficult than channel routing. In this paper, an O(NlogN) region definition and ordering assignment (RDAOA) algorithm is proposed to minimize the number of switchboxes for the routing phase, where N is the number of vertices in a channel precedence graph. Several examples have been tested on the proposed algorithm, and the experimental results are listed and compared.