Partial Order Reduction for State/Event Systems Shuanglong Kan 1,2(B ) , Zhiqiu Huang 1,2 , and Zhe Chen 1,2 1 College of Computer Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing, China {kanshuanglong,zqhuang,zhechen}@nuaa.edu.cn 2 Collaborative Innovation Center of Novel Software Technology and Industrialization, Nanjing, China Abstract. State/Event Linear Temporal Logic (SE-LTL) provides a concise and intuitive way to express properties incorporating both states and events. However, as SE-LTL is not preserved under classical stutter- equivalence, conventional Partial Order Reduction (POR) cannot be directly used to check them. In this paper, we propose a novel technique to exploit POR for checking SE-LTL. This technique detects a “state part ” of a B¨ uchi automaton (BA) translated from an SE-LTL formula. POR is integrated into the construction of the synchronous products of BAs and Labeled Kripke Structures (LKS), where “state parts ” direct the use of POR. The integrated POR modifies conventional POR by introducing an identification of visible actions with respect to events. In addition, we compare our technique with the existing POR for weak SE-LTL and give a method to combine them to obtain more reduction. We have implemented our technique in the SPIN model checker. The experimental results illustrate the potential of the technique for reduc- tion compared with pure state-based POR and SE-LTL model checking without POR. 1 Introduction In modular and component-based software, communication proceeds via events and is commonly data-dependent. In order to apply existing model checking techniques [3, 14] to such software, we need to provide formalisms which incor- porate both events and states. Modeling techniques based on annotated finite state automata might be either state-based or event-based. Although these two frameworks are interchangeable, converting from one representation to the other often results in a significant enlargement of the state space. In addition, both approaches are not practical when it comes to modular software, in which events This work was supported by the National High-tech R&D Program of China (863 Program) under Grant No. 2015AA015303, Funding of Jiangsu Innovation Program for Graduate Education KYLX 0315, the Fundamental Research Funds for the Cen- tral Universities, Joint Research Funds of National Natural Science Foundation of China and Civil Aviation Administration of China (U1533130). c  Springer International Publishing AG 2016 K. Ogata et al. (Eds.): ICFEM 2016, LNCS 10009, pp. 329–345, 2016. DOI: 10.1007/978-3-319-47846-3 21