Hierarchical State Machines as Modular Horn Clauses

TL;DR

This paper introduces a new method to translate hierarchical state machines into modular Horn clauses, preserving their structure and modal behavior, which enhances safety analysis of embedded systems.

Contribution

It presents a novel compilation technique that accurately converts hierarchical state machines into modular Horn clauses, maintaining their structural and modal information.

Findings

Preserves modal behavior during compilation.

Improves safety analysis tractability.

Maintains structural information of state machines.

Abstract

In model based development, embedded systems are modeled using a mix of dataflow formalism, that capture the flow of computation, and hierarchical state machines, that capture the modal behavior of the system. For safety analysis, existing approaches rely on a compilation scheme that transform the original model (dataflow and state machines) into a pure dataflow formalism. Such compilation often result in loss of important structural information that capture the modal behaviour of the system. In previous work we have developed a compilation technique from a dataflow formalism into modular Horn clauses. In this paper, we present a novel technique that faithfully compile hierarchical state machines into modular Horn clauses. Our compilation technique preserves the structural and modal behavior of the system, making the safety analysis of such models more tractable.