Hybrid quadratic placement with multiple linear system solvers

摘要

A method of designing a layout of an integrated circuit first places logic cells in an initial region of the integrated circuit using a first placement algorithm then, after partitioning the initial region into two or more partitioned regions, uses a second placement algorithm (different from the first placement algorithm) to place a portion of the logic cells in at least one of the partitioned regions. The placement algorithms are preferably quadratic placement algorithms such as the conjugate gradient placement algorithm and the successive over-relaxation placement algorithm. The selection of the particular placement algorithm to be used may be based on, e.g., the cut level or the number moveable objects for the given partition region.