A novel approach to parameterized verification of cache coherence protocols

Abstract

Parameterized verification of parameterized protocols like cache coherence protocols is an important but hard problem. Our tool paraVerifier handles this hard problem in a unified framework: (1) it automatically discovers auxiliary invariants and the corresponding causal relations from a small reference instance of the verified protocol; (2) the above invariants and causal relation information are automatically generalized into a parameterized form to construct a parameterized formal proof in a theorem prover (e.g., Isabelle). Our method is successfully applied to typical benchmarks including snooping and directory cache coherence protocol benchmarks. The correctness of these protocols is guaranteed by a formal and readable proof which is automatically generated. The notoriously hard FLASH protocol, which is at an industrial scale, is also verified.

Accelerated Verification of Parametric Protocols with Decision Trees

“…Recently, an automatic proving approach [7], [8], [9] is proposed by Li et al to address the above research problem, and their central idea is to guide a theorem prover by providing inductive invariant candidates. In their approach, an inductive invariant is an invariant that is satisfied by the initial state and preserved by each guarded command of the protocol.…”

“…RS) of an instance of the parametric protocol under verification and record our knowledge about RS as a decision tree. Then we construct candidates of invariants by adopting an earlier algorithm as proposed in the literature [7], [8], [9], and filter true invariants according to the knowledge obtained in the first step. After proper generalization, the selected invariants can be used to construct a formal proof for parameterized verification.…”

“…• We implement the extended decision-tree based learning approach as a teacher to classify the data sheet generated from the RS of the protocol. We integrate the teacher into the framework of paraVerifier [7], [8], [9] to automatically find invariants and to prove parametric cache coherence protocols. We conduct experiments successfully on typical benchmarks.…”

L-CMP: an automatic learning-based parameterized verification tool

“…It computes over-approximations of backward reachable states that are checked to be unreachable in the parameterized system [7]. Li et al proposed a method to automatically generate auxiliary invariants from a small reference instance of protocols and construct a parameterized formal proof in the theorem prover Isabelle [12]. Compared with these works, L-CMP provides a simpler way to verify parameterized protocols, and the auxiliary invariants it obtains are more understandable and straightforward.…”

“…Parameterized concurrent systems, in particular, cache coherence protocols, exist in many practical applications [12]. Verifying such systems has attracted considerable academic interests due to its practical importance [13].…”