
We present a novel algorithm for parallel solving of SMT problems based on a partitioning process that divides the original problem into a tree structure in an iterative way. By enabling node revisiting, the new method addresses the problem of partitioning divergence found in prior approaches that frequently leads to longer runtimes compared to sequential results. The resulting algorithm is highly flexible, offers a combination of partitioning, portfolio solving, and clause sharing, allows the use of various partitioning functions, and scales gracefully with the available resources. We implemented the new approach in the tool SMTS on top of the efficient sequential SMT solver OpenSMT. Our experimental results demonstrate a substantial improvement over OpenSMT in logics QF_LRA and QF_LIA even when the partitioning approach utilizes just a single solver. Notably, SMTS has consistently dominated several divisions of the annual competition of parallel SMT solvers.
Metric Interval Temporal Logic ( ) is a popular formalism for specifying properties of reactive systems with timing constraints. Existing approaches to using in verification tasks, however, have notable drawbacks: they either support only limited fragments of the logic (the future only fragment [] ) or allow for only incomplete verification. This paper introduces MightyPPL , a new tool for translating formulae in Metric Interval Temporal Logic with Past and Pnueli modalities ( ) over the pointwise semantics into timed automata, enabling satisfiability and model checking of this expressive specification logic over both finite and infinite timed words. MightyPPL optimises performance via specialised constructions for simple cases, a novel symbolic transition encoding, and a symmetry reduction technique that yields an exponential improvement in reachable discrete states. The tool generates language-equivalent automata compatible with back-ends such as Uppaal, TChecker, and LTSmin. Our evaluation demonstrates that MightyPPL significantly outperforms the state-of-the-art tool MightyL on future-only fragments and across various benchmarks.
We present a new algorithm to efficiently minimize state spaces with respect to branching bisimilarity. Our approach combines signature-based refinement with Hopcroft’s “process-the-smaller-half” optimization to avoid unnecessary computation. This combination results in a conceptually simpler and empirically faster algorithm for state space minimization modulo branching bisimilarity. While the theoretical worst-case complexity is slightly worse than existing algorithms, empirical evaluations on benchmarks demonstrate significantly better performance.
goblitch is a new verification toolchain for reachability safety that combines the abstract interpreter Goblint with the witness validator Witch. goblitch integrates these two tools in a refinement loop where Goblint repeatedly builds an abstract reachability graph and Witch decides whether an error path in the current graph corresponds to any real program execution. Experiments show that goblitch produces many False results and no incorrect results. Moreover, in the category C.ReachSafety, it produces more True results than Goblint.
ReFuncTion is a static analyzer designed for proving conditional termination (resilience), and functional program properties expressed in Computation Tree Logic (CTL). The tool automatically infers piecewise-defined ranking functions and sufficient preconditions by means of abstract interpretation.
Equivalence checking of quantum circuits is a central verification task in quantum computing, ensuring the correctness of circuit optimizations, hardware mappings, and compilation pipelines. Among the primary symbolic methods for this purpose, the path-sum formalism provides a compact representation with powerful reduction rules that yield a canonical form for the classically simulable Clifford fragment, but confluence fails beyond the Clifford fragment. We introduce a new weighted model counting (WMC) encoding for path-sums and combine it with the existing path-sum reductions to obtain a verifier that is both complete and efficient. Our method applies reductions whenever possible and invokes the WMC-based decision procedure on the residual path-sum, yielding a complete semantic check up to a global phase. We implement the approach and evaluate it on standard benchmarks. Results show that the hybrid method outperforms either component in isolation and competes with state-of-the-art tools.
According to common belief, the Java memory model is broken. In the past, several approaches have proposed repairs, often only to find new programs exhibiting unexpected, unintuitive behavior or the model forbidding standard compiler optimizations. The complexity of defining a memory model for concurrent Java lies in the fact that it requires a multi-execution model. Multi-execution models need to inspect many potential executions of a program in order to find the valid ones. Tools automatically validating novel proposals of Java memory models are, however, largely lacking. To alleviate this problem, we introduce jMT, a novel tool for constructing multi-execution semantics for concurrent Java programs. jMT relies on single-execution models defining well-formed execution graphs, based on which it builds valid multi-execution semantics via causality checking. Thereby, jMT supports evaluating new proposals of Java memory models (JMMs) on a per-program basis. jMT can furthermore be employed for testing the conformance of JMMs to existing compilation schemes and compilers. Our evaluation of jMT on 169 litmus tests reveals a number of interesting insights into existing JMMs.
We present ReVEAL, a graph-learning-based method for reverse engineering of multiplier architectures to improve algebraic circuit verification techniques. Our framework leverages structural graph features and learning-driven inference to identify architecture patterns at scale, enabling robust handling of large optimized multipliers. We demonstrate applicability across diverse multiplier benchmarks and show improvements in scalability and accuracy compared to traditional rule-based approaches. The method integrates smoothly with existing verification flows and supports downstream algebraic proof strategies.
We introduce VeriStruct, a novel framework that extends AI-assisted automated verification from single functions to more complex data structure modules in Verus. VeriStruct employs a planner module to orchestrate the systematic generation of abstractions, type invariants, specifications, and proof code. To address the challenge that LLMs often misunderstand Verus' annotation syntax and verification-specific semantics, VeriStruct embeds syntax guidance within prompts and includes a repair stage to automatically correct annotation errors. In an evaluation on eleven Rust data structure modules, VeriStruct succeeds on ten of the eleven, successfully verifying 128 out of 129 functions (99.2
Model checking of real-time systems is a well-studied topic, with Metric Interval Temporal Logic ( ) playing a key role in expressing timed properties. We present Tempora , a new tool for model checking under pointwise semantics, that integrates both past and future modalities. Tempora is based on a recent translation from to the model of Generalized Timed Automata (GTA) [3] and the zone-based algorithms for reachability and liveness in GTA [2, 3]. A straightforward implementation of the construction proposed in [3] falls short of state-of-the-art performance. Through a series of conceptual and engineering optimizations, we significantly improve its scalability and obtain a tool that outperforms existing approaches. In this work, we present the key techniques underlying these improvements and introduce our tool.
SliQSim, originally developed as the first exact quantum circuit simulator, is extended in this paper to provide capabilities for the analysis and verification of quantum states. It provides an interface for users to specify interested quantum states for querying the exact probability or expectation value of a user-defined property. Case studies on three quantum algorithms show the unique capability of SliQSim benefiting exact quantum circuit analysis and verification, beyond the support by other tools.
ESBMC v7.7 improves the verification of concurrent C programs by incorporating techniques such as dynamic thread scheduling, incremental SMT solving, and partial order reduction (POR). These improvements enhance the tool’s performance, particularly in exploring complex multi-threaded executions. The new scheduler prioritizes higher-thread identifiers during context switches, which helps explore deeper program states. The use of incremental SMT solving and a refined POR algorithm reduces the exploration of unreachable interleavings and redundant states. These updates enable ESBMC to detect bugs faster, making it a more effective tool for ensuring the safety of multi-threaded applications.
GPUexplore ^prob is an extension of GPUexplore that constructs state spaces of Markov Chains and performs probabilistic model checking entirely on a GPU. It can construct the state space of a Discrete-Time Markov Chain and verify that it satisfies a given Probabilistic Computation-Tree Logic formula. We present the tool, and experimentally compare with Storm, demonstrating its effectiveness.
We present advances we brought to Mopsa for SV-Comp 2025. Most notably, Mopsa now supports bounded trace partitioning, constant widening with thresholds, and can check that all memory has been correctly deallocated. Further, Mopsa now integrates a sound support of bitfields. While Mopsa at SV-Comp previously relied on a fixed, homogeneous set of configurations to verify tasks, it can now automatically leverage semantic information from a previous analysis to trigger heuristic precision improvements in further analyses. With these improvements, Mopsa wins a silver medal in the SoftwareSystems category and ranks fifth in the NoOverflows category.