Toward a backward model checking

Abstract

This paper presents a new method of program verification, backward incremental model checking (BIMC). BIMC is a backward compositional technique to check, statically safety properties of C programs. A program is a hierarchy of blocks. Blocks are analysed in reverse order until we prove or disprove property. To our knowledge, it is the first work dealing with program model checking in a backward way. We define a new method: ASMA for program modelling. ASMA allows separating a program into two components: the data model and the control model. This approach allows an easy program manipulation. BIMC starts the verification with a minimal set P0 which is then incrementally extended each time needed. The weakest precondition concept is applied on the two models in an adequate and incremental way. BIMC allows handling programs containing function calls and pointers. All the techniques described in this paper are illustrated by clarifying examples.