Verification of Hierarchical Graph Structures

Embedded systems software is being used for increasingly complex and safety-critical applications. In order to ensure the safe and successful operation of these applications we must verify their safety and mission critical properties, and reduce relianceon a testing process that can only detect the presence of faults. Model checking is a verification technique that allows users to verify cross-cutting properties of systems. Model checking has been successfully applied to hardware designs, but has onlyyielded limited success in the software verification realm due to scalability issues. Exploitation of modularity has been recognized as a means of increasing the scalability of model checking. We propose a new context-free language reachability based modelchecking technique that allows us to exploit the inherent modularity in procedural abstraction. We also propose using our dependence graph and program slicing technology to construct models of a reduced size. We believe our technology will significantlyincrease the scalability of model checking, allowing it to be applied to complex safety-critical embedded systems.The proposed system will be of use in improving the quality of safety and mission-critical software in embedded systems. This system willallow companies to develop highly reliable embedded real-time systems.