A mechanism is provided for performing a detailed routing of a net joining ports in an integrated circuit. Extended port regions are created for the ports of the net of the integrated circuit, the extended port regions being shaped in such a way as to guarantee routing access to the ports. A wire corresponding to the net is then placed and the extended port regions of the ports are trimmed, thus identifying essential port regions required for connecting the wire to the ports and dispensable port regions not required for connecting the wire to the ports. The wiring resources are then updated by releasing the dispensable port regions so that the dispensable port regions no longer constitute parts of the ports.