Bisection based placement for the X architecture

Abstract

Rising interconnect delay and power consumption have motivated the investigation of alternative integrated circuit routing architectures. In particular, the X Architecture, which features preferred routing in diagonal directions, has gained a measure of industry support, and has even been validated at 65nm. While there has been extensive study of Manhattan design methods, there are markedly fewer published results for nonManhattan design. To help fill this gap, we study a patented placement method for the X Architecture; to our knowledge, there have been no prior published results for the method. Surprisingly, we find that the patented method in fact performs worse than traditional Manhattan methods - for both Manhattan and X routing metrics. We also present a theoretic formulation which explains why solution quality is degraded. Many groups in industry are evaluating the merits of non-Manhattan routing architectures. By providing concrete experimental results, we hope to improve the accuracy of these evaluations. © 2007 IEEE.