An accurate algorithm for computing mutation coverage in model checking

Property coverage is an important way to evaluate the completeness of model checking. Most of the property coverage metrics are based on mutation coverage, obtained by mutating the design and checking the property's ability to detect the mutation. Due to the complexity of computing mutation coverage in model checking, the previous methods resort to some approximate algorithms which tend to give pessimistic estimation of state coverage, and can only deal with a limited subset of Computation Tree Logic (CTL). In this paper, we present an improved algorithm to compute mutation coverage for arbitrary CTL formulas with high accuracy. Experimental results show that the proposed algorithm can identify a great number of covered states missed by a previous method. Meanwhile, the extension to the complete CTL set makes it easy to write all kinds of properties to describe the features of the design better.