n-pass n-detection fault simulation and its applications

An n-detection fault simulation process called n-pass n-detection fault simulation is described. n-pass n-detection fault simulation can be implemented such that it has the same computational complexity (and run time) as the conventional n-detection fault simulation process; however, it is more effective for applications where it is necessary to identify tests that detect large numbers of faults. One such application considered in this work is that of ordering a given test set so as to steepen its fault coverage curve. Experimental results are presented to demonstrate that improved test ordering is obtained by using the proposed n-pass n-detection fault simulation process using approximately the same run time as when conventional n-detection fault simulation is used. n-pass n-detection fault simulation is also effective in cases where the value of n is required to change dynamically during the fault simulation process. This is useful in order to accommodate a limit on the run time of n-detection fault simulation, or when it is not possible to specify a value for n in advance.