A Logic of Singly Indexed Arrays

Peter Habermehl (1) , Radu Iosif (2) , Tomáš Vojnar (3)

1 Automates et Applications [LIAFA]
2 VERIMAG - IMAG - VERIMAG
3 FIT / BUT - Faculty of Information Technology [Brno]

We present a logic interpreted over integer arrays, which allows difference bound comparisons between array elements situated within a constant sized window. We show that the satisfiability problem for the logic is undecidable for formulae with a quantifier prefix {∃, ∀} * ∀ * ∃ * ∀ *. For formulae with quantifier prefixes in the ∃ * ∀ * fragment, decidability is established by an automata-theoretic argument. For each formula in the ∃ * ∀ * fragment, we can build a flat counter automaton with difference bound transition rules (FCADBM) whose traces correspond to the models of the formula. The construction is modular, following the syntax of the formula. Decidability of the ∃ * ∀ * fragment of the logic is a consequence of the fact that reachability of a control state is decidable for FCADBM.

Domaines: Logique en informatique [cs.LO]

Peter Habermehl, Radu Iosif, Tomáš Vojnar. A Logic of Singly Indexed Arrays. Logic for Programming, Artificial Intelligence, and Reasoning, 15th International Conference, LPAR 2008,, Nov 2008, Doha, Qatar. ⟨10.1007/978-3-540-89439-1_39⟩. ⟨hal-01418915⟩