This is an old revision of the document!
Abstract: We consider the termination problem of programs manipulating tree-like dynamic data structures. Our approach is based on an abstract-check-refine loop. We use abstract regular tree model-checking to infer invariants of the program. Then, we translate the program to a counter automaton which simulates it. If the counter automaton can be shown to terminate using existing techniques, the program terminates. If not, we analyze the possible counterexample given by a counter automata termination checker and either conclude that the program does not terminate, or else refine the abstraction and repeat. We show that the spuriousness problem for lasso-shaped counterexamples is decidable in some non-trivial cases. We applied the method successfully on several interesting case studies.
Joint work with Peter Habermehl, Tomas Vojnar and Adam Rogalewicz
Abstract: We extend combinatorial imperfect information games to a multi-player setting, where information is exchanged with respect to hierarchical constraints. We show that this class of games can be used for model checking first-order logic on structures, where elements are built inductively. We focus on structures with relations given by automata where these games have finite arenas. Assuming that players alternate their moves, it is possible to decide the winning coalition in such a game. We discuss how this game-based representation can be exploited algorithmically.