Method and apparatus for identifying propagation for routes with diagonal edges

摘要

Some embodiments provide a hierarchical method of routing nets within a particular region of a circuit layout. Each net has a set of pins. The method initially partitions the particular region into a first set of sub-regions. For each net, the method identifies a first route that connects a group of first-set sub-regions containing the first net's pins; where some of the routes have at least one route-edge that is at least partially diagonal. The method then partitions the sub-regions into a second set of smaller sub-regions. For a first net, the method identifies a propagation of the first-net's first route into the second-set sub-regions based on congestion between the second-set sub-regions. It then adjusts the congestion between the second set sub-regions based on the identified propagation. For a second net, the method then identifies a propagation of the second-net's first route into the second-set sub-regions based on congestion between the second-set sub-regions.