Using a Bounded Model Checker for Test Generation: How to Kill Two Birds with One SMT Solver

Automated test generation has received a lot of attention in recent decades, because it is one possible solution to the problems inherent to software testing: the need to write tests in the first place and providing test coverage for the human factor. De facto the most promising technique to automatically generate a test is dynamic symbolic execution assisted by an automated constraint solver, e.g., an SMT solver. This process is very similar to bounded model checking, which also deals with generating models from source code, asserting logic properties in it, and processing the returned model. This paper describes a prototype unit test generator for C based on a working bounded model checker called Borealis and shows that these two techniques are very similar and can be easily implemented using the same basic components. The prototype test generator has been evaluated on a number of examples and has shown good results in terms of test coverage and test excessiveness.