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arXiv · 1909.05537

Tasks in Modular Proofs of Concurrent Algorithms

Armando Castañeda·Aurélie Hurault·Philippe Quéinnec·Matthieu Roy
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Abstract

Proving correctness of distributed or concurrent algorithms is a mind-challenging and complex process. Slight errors in the reasoning are difficult to find, calling for computer-checked proof systems. In order to build computer-checked proofs with usual tools, such as Coq or TLA+, having sequential specifications of all base objects that are used as building blocks in a given algorithm is a requisite to provide a modular proof built by composition. Alas, many concurrent objects do not have a sequential specification. This article describes a systematic method to transform any task, a specification method that captures concurrent one-shot distributed problems, into a sequential specification involving two calls, Set and Get. This transformation allows system designers to compose proofs, thus providing a framework for modular computer-checked proofs of algorithms designed using tasks and sequential objects as building blocks. The Moir&Anderson implementation of renaming using splitters is an iconic example of such algorithms designed by composition.

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Armando Castañeda, Aurélie Hurault, Philippe Quéinnec, Matthieu Roy. 2019-09-12. Tasks in Modular Proofs of Concurrent Algorithms. https://doi.org/10.1007/978-3-030-34992-9_6

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