1. A method, comprising: adding signal path information to a configuration file, wherein the signal path information identifies a path in an integrated circuit that has a source in a first clock domain and a destination in a second clock domain; and adding one or more timing parameters for the path to the configuration file, wherein the one or more timing parameters specify a propagation delay from the source to the destination; wherein the configuration file is usable by a simulation tool to simulate operation of the integrated circuit.