Slicing of state-based models

Abstract

System modeling is a widely used technique to model state-based systems. Several state-based languages are used to model such systems, e.g., EFSM, SDL and State Charts. Although state-based modeling is very useful, system models are frequently large and complex and are hard to understand and modify. Slicing is a well-known reduction technique. Most of the research on slicing is code-based.There has been limited research on specification-based slicing and model-based slicing. In this paper, we present an approach to slicing state-based models, in particular EFSM models. Our approach automatically identifies the parts of the model that affect an element of interest using EFSM dependence analysis. Slice reduction techniques are then used to reduce the size of the EFSM slice. Our experience with the presented slicing approach showed that significant reduction of state-based models could be achieved.

Control Dependence for Extended Finite State Machines

“…Korel et al [KSTV03] present a definition of control dependence for EFSMs in terms of post dominance that requires execution paths to lead to an exit state.…”

“…Definition 3 (Post Dominance [KSTV03]). Let Y and Z be two states and T be an outgoing transition from Y .…”

“…Definition 4 (Insensitive Control Dependence (ICD) [KSTV03]). Transition T k is control dependent on transition T i if: A node is either a statement node (which has a single successor) or a predicate node (which has two successors, labelled with T or F for the true and false cases respectively).…”

“…Work on slicing FSM models began with the work of Heimdahl et al in the late 1990s [HW97,HTW98], followed by Wang et al [WDQ02] and then in 2003 by the work of Korel et al [KSTV03] and more recently by Langenhove and Hoogewijs [LH07] and by Labbé et al [LGP07,LG08].…”

“…Recent work on control dependence has only considered the non-termination sensitive option [LGP07,LG08]. The non-termination insensitive option was explored by Korel et al [KSTV03], but only for the restricted class of state machines that guarantee to have an exit state. Heimdahl et al [HW97,HTW98] have a different notion of control dependence which is not a structural property of the graph of FSMs but is based on the dependency relation between events and generated events.…”