1. A computer-implemented method for determining whether to use hard rules or whether to use soft rules for a first g-cell during global routing of an integrated circuit design, comprising: performing global routing with one or more of the hard rules which comprise a first requirement for a routing demand and guide the global routing; determining, by using at least one processor, whether a first g-cell in the global routing is overcongested by at least using one or more of the soft rules, wherein the one or more of the soft rules comprise a second requirement for the routing demand and are not the hard rules; identifying or creating a marking of the first g-cell as using soft rule to improve at least a performance aspect of the integrated circuit design by using at least some of the soft rules where the first g-cell is determined not to be overcongested in the act of determining whether the first g-cell is overcongested, wherein the marking of the first g-cell indicates what rule the first g-cell is to be based at least in part upon during a routing of the integrated circuit design; and storing a result of the act of identifying the marking of the first g-cell in a tangible computer accessible medium for use in subsequent routing or displaying the result on a display apparatus.