Delay modes let you alter the delay values specified in your models by using command-line options and compiler directives. You can ignore all delays specified in your model or replace all delays with a value of one simulation time unit. You can also replace delay values in selected portions of the model.
You can specify delay modes on a global basis or on a module basis. If you assign a specific delay mode to a module, all instances of that module simulate in that mode. The delay mode of each module is determined at elaboration time and cannot be altered dynamically.