A system for generating a layout of an integrated circuit is disclosed. The system includes at least one processing unit for executing computer programs, a graphical-user-interface for viewing representations of the integrated circuit on a display and observing the layout of the integrated circuit, and a memory for storing databases of the integrated circuit. The system further includes means for retrieving locations of a plurality of devices from a schematic of the integrated circuit, means for retrieving user-specified placement constraints, and means for placing the devices in accordance with the locations and the user-specified placement constraints.