Juggrnaut: Graph Grammar Abstraction for Unbounded Heap Structures

We present a novel abstraction framework for heap data structures that uses graph grammars, more precisely context-free hyperedge replacement grammars, as an intuitive formalism for efficiently modeling dynamic data structures. It aims at extending finite-state verification techniques to handle pointer-manipulating programs operating on complex dynamic data structures that are potentially unbounded in their size. We demonstrate how our framework can be employed for analysis and verification purposes by instantiating it for binary trees, and by applying this instantiation to the well-known Deutsch-Schorr-Waite traversal algorithm. Our approach is supported by a prototype tool, enabling the quick verification of essential program properties such as heap invariants, completeness, and termination.