Identifying hierarchical chip design intellectual property through digests

Abstract

One method implementation disclosed includes detecting matching leaf cells that have functionally identical designs (optionally, similar designs) and assigning matching names for the matching leaf cells to replace original, non-matching names. Optionally, digests can be calculated for the leaf cells and used to detect similarities and/or differences. The matching names are propagated to at least some higher-level cells in the hierarchical design, in place of the original names. The method can further include calculating digests for at least some of the higher level cells after the propagating of the matching names into the higher level cells. Various design matching technologies can be used in combination with cell renaming and new name propagation, not limited to use of digests. Dependency chains can be calculated to improve propagation of names through the hierarchy.