Computing relaxed abstract semantics w.r.t. quadratic zones precisely

Abstract

In the present paper we compute numerical invariants of programs by abstract interpretation. For that we consider the abstract domain of quadratic zones recently introduced by Adjé et al. [2]. We use a relaxed abstract semantics which is at least as precise as the relaxed abstract semantics of Adjé et al. [2]. For computing our relaxed abstract semantics, we present a practical strategy improvement algorithm for precisely computing least solutions of fixpoint equation systems, whose right-hand sides use order-concave operators and the maximum operator. These fixpoint equation systems strictly generalize the fixpoint equation systems considered by Gawlitza and Seidl [11]. © 2010 Springer-Verlag.