An octagonal geometry compactor

Layout compactors have been widely adopted by symbolic layout systems to compact circuit layout. A common limitation among current state-of-the-art compactors is that they can only compact orthogonal geometries. The author describes a one-dimensional compactor that can compact arbitrary octagonal geometries. The compactor is based on the constraint graph approach. The octagonal geometry compactor offers significant area saving over the orthogonal geometry compactors when 45°-angle wires and edges are involved. The algorithms to compact 45- and 90° -angle geometries are described