Abstract We present a case study on proof-driven software understanding of mature, security-critical infrastructure. While formal methods are traditionally applied during the design phase, we present our experience applying formal reasoning onto a mature industrial C++ codebase. We focus on a formal analysis of the core algorithm that implements the Stellar blockchain’s order book. By combining large language models (LLMs), Prototype Verification System (PVS), and Seahorn , we are able to prove core properties of the production codebase. Our approach also identified an inconsistency in documentation related to the reachability of an exception location. Most importantly, however, we produce artifacts that make it easy for code changes to be checked against established invariants. This work demonstrates how the strategic combination of theorem proving and model checking provides a path for delivering robust assurance to legacy systems.

Abstract We release the first tool suite implementingMoXI(Model eXchange Interlingua), an intermediate language for symbolic model checking designed to be an international research-community standard and developed by a widespread collaboration under a National Science Foundation (NSF) CISE Community Research Infrastructure initiative. Although we focus here on hardware verification, theMoXIlanguage is useful for software model checking and verification of infinite-state systems in general.MoXIbuilds on elements of SMT-LIB 2; it is easy to add new theories and operators. Our contributions include: (1) introducing the first tool suite of automated translators into and out of the new model-checking intermediate language; (2) composing an initial example benchmark set enabling the model-checking research community to build future translations; (3) compiling details for utilizing, extending, and improving upon our tool suite, including usage characteristics and initial performance data. Experimental evaluations demonstrate that compiling SMV-language models throughMoXIto perform symbolic model checking with the tools from the last Hardware Model Checking Competition performs competitively with model checking directly vianuXmv.