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arXiv · 1208.5895

Two for the Price of One: Lifting Separation Logic Assertions

Jacob Thamsborg·Lars Birkedal·Hongseok Yang
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Abstract

Recently, data abstraction has been studied in the context of separation logic, with noticeable practical successes: the developed logics have enabled clean proofs of tricky challenging programs, such as subject-observer patterns, and they have become the basis of efficient verification tools for Java (jStar), C (VeriFast) and Hoare Type Theory (Ynot). In this paper, we give a new semantic analysis of such logic-based approaches using Reynolds's relational parametricity. The core of the analysis is our lifting theorems, which give a sound and complete condition for when a true implication between assertions in the standard interpretation entails that the same implication holds in a relational interpretation. Using these theorems, we provide an algorithm for identifying abstraction-respecting client-side proofs; the proofs ensure that clients cannot distinguish two appropriately-related module implementations.

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Jacob Thamsborg, Lars Birkedal, Hongseok Yang. 2012-08-29. Two for the Price of One: Lifting Separation Logic Assertions. https://doi.org/10.2168/lmcs-8(3:22)2012

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