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arXiv · 1601.02132

Possible values: exploring a concept for concurrency

Cliff B. Jones·Ian J. Hayes
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Abstract

An important issue in concurrency is interference. This issue manifests itself in both shared-variable and communication-based concurrency --- this paper focusses on the former case where interference is caused by the environment of a process changing the values of shared variables. Rely/guarantee approaches have been shown to be useful in specifying and reasoning compositionally about concurrent programs. This paper explores the use of a "possible values" notation for reasoning about variables whose values can be changed multiple times by interference. Apart from the value of this concept in providing clear specifications, it offers a principled way of avoiding the need for some auxiliary (or ghost) variables whose unwise use can destroy compositionality.

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Cliff B. Jones, Ian J. Hayes. 2016-01-09. Possible values: exploring a concept for concurrency. https://arxiv.org/abs/1601.02132

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