Applications of the connection machine to VLSI CAD. I. A parallel channel router

The authors report their first experiments in integrating the connection machine into VLSI CAD (computer-aided design) software systems. A parallel channel router was implemented using an incremental analysis technique as a case to illustrate the applicability of the architecture. A routing channel implemented in a grid system is discretized, with each layer defining a net segmented into a finite number of unit segments and analyzed during each step in the algorithm. The set comprising the tips of all nets forms the domain elements operated upon. An optimum solution is found by concurrently minimizing the distance to the other end of each net. The tip moves from one live processor to another selected as the best move at each step. The authors study the special case of channel routing in VLSI and show how the parallel aspect of such a problem is used efficiently to route pairs of networks concurrently