Formal verification of a deadlock detection algorithm

TL;DR

This paper presents a formally verified deadlock detection algorithm for on-chip networks with wormhole switching, ensuring correctness through ACL2 proof, aiming for an efficient executable implementation.

Contribution

It introduces a formally specified and proven correct deadlock detection algorithm for on-chip networks, with a top-down proof methodology using ACL2.

Findings

Algorithm verified correct in ACL2

Specification includes constrained functions with defun-sk

Proof process ensured algorithm flawlessness

Abstract

Deadlock detection is a challenging issue in the analysis and design of on-chip networks. We have designed an algorithm to detect deadlocks automatically in on-chip networks with wormhole switching. The algorithm has been specified and proven correct in ACL2. To enable a top-down proof methodology, some parts of the algorithm have been left unimplemented. For these parts, the ACL2 specification contains constrained functions introduced with defun-sk. We used single-threaded objects to represent the data structures used by the algorithm. In this paper, we present details on the proof of correctness of the algorithm. The process of formal verification was crucial to get the algorithm flawless. Our ultimate objective is to have an efficient executable, and formally proven correct implementation of the algorithm running in ACL2.