METHOD AND APPARATUS FOR COMPUTING A DETAILED ROUTABILITY ESTIMATION

摘要

One embodiment of the present invention provides a system that computes a routability estimation across a collection of local routing regions associated with a circuit layout. This system first selects a first local routing region associated with a route overflow, wherein a respective local routing region is associated with an estimation of a number of route overflows for routing layers in a region of the circuit layout. Furthermore, a respective routing layer is associated with a preferred direction variable D. Next, the system transfers an overflow value k in direction d away from an overflowing routing layer for the first local routing region to a second local routing region, which has the capacity to handle an overflow of k or more routes in a direction d. Finally, the system computes a global routability estimation as a function of a global overflow cost and an adjacent overflow cost.