Abstract: Some embodiments provide a system for managing violations during physical verification. The system may identify a design-rule-check (DRC) violation by applying a set of DRC rules to a layout. The system can then receive an error classification from the user which specifies how the DRC violation is to be handled. Next, the system can store the DRC violation, the user-selected error classification, and a user identifier associated with the user in a database. If the user is not authorized to approve the error classification, the database can indicate that the error classification has not been approved. Later, a user who is authorized to approve the error classification can approve the error classification. The system can determine if a cell is known, and if so, the system can use the violations and error classifications stored in the database to speed up the verification process.

Abstract: Some embodiments provide a system for managing violations during physical verification. The system may identify a design-rule-check (DRC) violation by applying a set of DRC rules to a layout. The system can then receive an error classification from the user which specifies how the DRC violation is to be handled. Next, the system can store the DRC violation, the user-selected error classification, and a user identifier associated with the user in a database. If the user is not authorized to approve the error classification, the database can indicate that the error classification has not been approved. Later, a user who is authorized to approve the error classification can approve the error classification. The system can determine if a cell is known, and if so, the system can use the violations and error classifications stored in the database to speed up the verification process.

Abstract: One embodiment of the present invention provides a system that computes feature density for a number of areas within a layout by moving a window across the layout, which allows the system to identify areas in the layout that violate a design rule. During operation, the system receives a layout. Next, the system places the window at a first location in the layout. The system then computes the feature density value based on the features within the window at the first location. Next, the system determines a second location in the layout based on the first location and the feature density value. The system then moves the window to the second location. Next, the system computes the feature density value based on the features within the window at the second location.