1. XGRouter: high-quality global router in X-architecture with particle swarm optimization Frontiers of Computer Science, 2015, 9(4):576–594 Genggeng LIU, Wenzhong GUO, Rongrong LI, Yuzhen NIU, Guolong CHEN

2. Problems & Ideas Problems of global routing in X-architecture: – During global routing, the routes of nets are allocated to each channel routing area and the channel routing problem in each channel area is defined explicitly. Then detailed routing determines the specific location in the channel area for each net guided by the global routing solution. – The X-grid consists of vertical columns, horizontal rows, and positive and negative diagonal tracks with slopes of 45 ◦ and 135 ◦, respectively. Ideas: – We propose XGRouter, a global routing procedure based on X-architecture that heavily relies on integer programming techniques, partition strategy and PSO. – A new ILP formulation which considers both the wire length minimization and the congestion uniformity is proposed.

3. Main Contributions Our proposed ILP formulation can solve the problem that the results are highly dependent on the ordering of the nets in sequential routers. It can achieve more uniform routing solution than the ILP formulation without congestion uniformity and is more scalable than the traditional ILP formulation. To our best knowledge, XGRouter is the first work to use the concurrent algorithm to solve the global routing problem in X-architecture and can achieve the high quality of solutions.