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Title: An Algebra of Alignment for Relational Verification
Relational verification encompasses information flow security, regression verification, translation validation for compilers, and more. Effective alignment of the programs and computations to be related facilitates use of simpler relational invariants and relational procedure specs, which in turn enables automation and modular reasoning. Alignment has been explored in terms of trace pairs, deductive rules of relational Hoare logics (RHL), and several forms of product automata. This article shows how a simple extension of Kleene Algebra with Tests (KAT), called BiKAT, subsumes prior formulations, including alignment witnesses for forall-exists properties, which brings to light new RHL-style rules for such properties. Alignments can be discovered algorithmically or devised manually but, in either case, their adequacy with respect to the original programs must be proved; an explicit algebra enables constructive proof by equational reasoning. Furthermore our approach inherits algorithmic benefits from existing KAT-based techniques and tools, which are applicable to a range of semantic models.  more » « less
Award ID(s):
2106845 2131476 2107169 1718713
PAR ID:
10427308
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
ACM Journals
Date Published:
Journal Name:
Proceedings of the ACM on Programming Languages
Volume:
7
Issue:
POPL
ISSN:
2475-1421
Page Range / eLocation ID:
573 to 603
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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