In the 14.1 ISE Simulation Tool (ISim), a new switch has been added to increase the simulation speed. This switch is as follows:
This switch allows for faster simulation times by disabling internal processing logic for combinatorial feed-through paths.
This switch is available only in the ISE 14.1 and later tool versions. For a solution to an earlier version of ISE tools, please contact Xilinx Technical Support for assistance.