Construction of Verifier Combinations Based on Off-the-Shelf Verifiers

Abstract

AbstractSoftware verifiers have different strengths and weaknesses, depending on properties of the verification task. It is well-known that combinations of verifiers via portfolio and selection approaches can help to combine the strengths. In this paper, we investigate (a) how to easily compose such combinations fromexisting, ‘off-the-shelf’ verification tools without changing them and (b) how much performance improvement easy combinations can yield, regarding the effectiveness (number of solved problems) and efficiency (consumed resources). First, we contribute a method to systematically and conveniently construct verifier combinations from existing tools, using the composition frameworkCoVeriTeam. We consider sequential portfolios, parallel portfolios, and algorithm selections. Second, we perform a large experiment on 8 883 verification tasks to show that combinations can improve the verification resultswithoutadditional computational resources. All combinations are constructed from off-the-shelf verifiers, that is, we use them as published. The result of our work suggests that users of verification tools can achieve a significant improvement at a negligible cost (only configure our composition scripts).