CoVEGI: Cooperative Verification via Externally Generated Invariants

Abstract

Software verification has recently made enormous progress due to the development of novel verification methods and the speed-up of supporting technologies like SMT solving. To keep software verification tools up to date with these advances, tool developers keep on integrating newly designed methods into their tools, almost exclusively by re-implementing the method within their own framework. While this allows for a conceptual re-use of methods, it nevertheless requires novel implementations for every new technique.In this paper, we employ cooperative verification in order to avoid re-implementation and enable usage of novel tools as black-box components in verification. Specifically, cooperation is employed for the core ingredient of software verification which is invariant generation. Finding an adequate loop invariant is key to the success of a verification run. Our framework named CoVEGI allows a master verification tool to delegate the task of invariant generation to one or several specialized helper invariant generators. Their results are then utilized within the verification run of the master verifier, allowing in particular for crosschecking the validity of the invariant. We experimentally evaluate our framework on an instance with two masters and three different invariant generators using a number of benchmarks from SV-COMP 2020. The experiments show that the use of CoVEGI can increase the number of correctly verified tasks without increasing the used resources.

Parallel Program Analysis via Range Splitting

“…Sequential portfolio approaches [44,61] run distinct, independent analyses in sequence while parallel portfolio approaches [91,12,57,65,66,96] execute various, independent analyses in parallel. Parallel white-box combinations [7,9,37,38,54,56,59,79] run different approaches in parallel, which exchange information for the purpose of collaboration. Next, we discuss cooperation approaches that split the search space as we do.…”

“…The idea of cooperative verification is to have different sorts of analyses cooperate on the task of software verification. This principle has already been implemented in various forms [16,19,33,59], in particular also as cooperations of testing and verification tools [10,39,41,42]. Such cooperations most often take the form of se-quential combinations, where one tool starts with the full task, stores its partial analysis result within some verification artefact, and the next tool then works on the remaining task.…”

Scalable Typestate Analysis for Low-Latency Environments

“…Also, several approaches testify alarms [1,38,39,45,48,49,53,72,82] to reduce the number of reported false alarms. To make verification more effective, analyses exchange information in sequential [5,22,66], alternating [3,11,24,55,57,60,73,77,92,100], or parallel [18,21,44,58] combinations. Our approach exchanges the predicate precision in a sequential combination.…”

“…To accomplish all three needs, one may require cooperative verification, result validation, and regression verification techniques. Cooperative verification techniques, e.g., [11,18,20,40,49,57,58,83,89,90] Our applications for reusing a predicate precision in a value analysis e.g., [15,16,39,45,53,61,75] target the trust in verification results. Instead of proving the correctness of a verification technique and its implementation, they use information provided by the verifier to validate its result, often using a different verifier.…”