Model Checker Execution Reports
This work addresses the issue for users of software model checkers who need insights into partial verification results, though it is incremental as it builds on existing techniques.
The paper tackles the problem of software model checkers often failing without providing information on what was checked, by introducing execution reports that detail incomplete checks. The approach was implemented in CPAchecker and evaluated empirically.
Software model checking constitutes an undecidable problem and, as such, even an ideal tool will in some cases fail to give a conclusive answer. In practice, software model checkers fail often and usually do not provide any information on what was effectively checked. The purpose of this work is to provide a conceptual framing to extend software model checkers in a way that allows users to access information about incomplete checks. We characterize the information that model checkers themselves can provide, in terms of analyzed traces, i.e. sequences of statements, and safe cones, and present the notion of execution reports, which we also formalize. We instantiate these concepts for a family of techniques based on Abstract Reachability Trees and implement the approach using the software model checker CPAchecker. We evaluate our approach empirically and provide examples to illustrate the execution reports produced and the information that can be extracted.