5,658 research outputs found
Program transformation for development, verification, and synthesis of programs
This paper briefly describes the use of the program transformation methodology for the development of correct and efficient programs. In particular, we will refer to the case of constraint logic programs and, through some examples, we will show how by program transformation, one can improve, synthesize, and verify programs
Abstract State Machines 1988-1998: Commented ASM Bibliography
An annotated bibliography of papers which deal with or use Abstract State
Machines (ASMs), as of January 1998.Comment: Also maintained as a BibTeX file at http://www.eecs.umich.edu/gasm
Transformations of CCP programs
We introduce a transformation system for concurrent constraint programming
(CCP). We define suitable applicability conditions for the transformations
which guarantee that the input/output CCP semantics is preserved also when
distinguishing deadlocked computations from successful ones and when
considering intermediate results of (possibly) non-terminating computations.
The system allows us to optimize CCP programs while preserving their intended
meaning: In addition to the usual benefits that one has for sequential
declarative languages, the transformation of concurrent programs can also lead
to the elimination of communication channels and of synchronization points, to
the transformation of non-deterministic computations into deterministic ones,
and to the crucial saving of computational space. Furthermore, since the
transformation system preserves the deadlock behavior of programs, it can be
used for proving deadlock freeness of a given program wrt a class of queries.
To this aim it is sometimes sufficient to apply our transformations and to
specialize the resulting program wrt the given queries in such a way that the
obtained program is trivially deadlock free.Comment: To appear in ACM TOPLA
Program Transformation for Development, Verification, and Synthesis of Software
In this paper we briefly describe the use of the program transformation methodology for the development of correct
and efficient programs. We will consider, in particular,
the case of the transformation and the development of constraint logic programs
Proving theorems by program transformation
In this paper we present an overview of the unfold/fold proof method, a method for proving theorems about programs, based on program transformation. As a metalanguage for specifying programs and program properties we adopt constraint logic programming (CLP), and we present a set of transformation rules (including the familiar unfolding and folding rules) which preserve the semantics of CLP programs. Then, we show how program transformation strategies can be used, similarly to theorem proving tactics, for guiding the application of the transformation rules and inferring the properties to be proved. We work out three examples: (i) the proof of predicate equivalences, applied to the verification of equality between CCS processes, (ii) the proof of first order formulas via an extension of the quantifier elimination method, and (iii) the proof of temporal properties of infinite state concurrent systems, by using a transformation strategy that performs program specialization
Verifying Monadic Second-Order Properties of Graph Programs
The core challenge in a Hoare- or Dijkstra-style proof system for graph
programs is in defining a weakest liberal precondition construction with
respect to a rule and a postcondition. Previous work addressing this has
focused on assertion languages for first-order properties, which are unable to
express important global properties of graphs such as acyclicity,
connectedness, or existence of paths. In this paper, we extend the nested graph
conditions of Habel, Pennemann, and Rensink to make them equivalently
expressive to monadic second-order logic on graphs. We present a weakest
liberal precondition construction for these assertions, and demonstrate its use
in verifying non-local correctness specifications of graph programs in the
sense of Habel et al.Comment: Extended version of a paper to appear at ICGT 201
12th International Workshop on Termination (WST 2012) : WST 2012, February 19ā23, 2012, Obergurgl, Austria / ed. by Georg Moser
This volume contains the proceedings of the 12th International Workshop on Termination (WST 2012), to be held February 19ā23, 2012 in Obergurgl, Austria. The goal of the Workshop on Termination is to be a venue for presentation and discussion of all topics in and around termination. In this way, the workshop tries to bridge the gaps between different communities interested and active in research in and around termination. The 12th International Workshop on Termination in Obergurgl continues the successful workshops held in St. Andrews (1993), La Bresse (1995), Ede (1997), Dagstuhl (1999), Utrecht (2001), Valencia (2003), Aachen (2004), Seattle (2006), Paris (2007), Leipzig (2009), and Edinburgh (2010). The 12th International Workshop on Termination did welcome contributions on all aspects of termination and complexity analysis. Contributions from the imperative, constraint, functional, and logic programming communities, and papers investigating applications of complexity or termination (for example in program transformation or theorem proving) were particularly welcome. We did receive 18 submissions which all were accepted. Each paper was assigned two reviewers. In addition to these 18 contributed talks, WST 2012, hosts three invited talks by Alexander Krauss, Martin Hofmann, and Fausto Spoto
Verification of Imperative Programs by Constraint Logic Program Transformation
We present a method for verifying partial correctness properties of
imperative programs that manipulate integers and arrays by using techniques
based on the transformation of constraint logic programs (CLP). We use CLP as a
metalanguage for representing imperative programs, their executions, and their
properties. First, we encode the correctness of an imperative program, say
prog, as the negation of a predicate 'incorrect' defined by a CLP program T. By
construction, 'incorrect' holds in the least model of T if and only if the
execution of prog from an initial configuration eventually halts in an error
configuration. Then, we apply to program T a sequence of transformations that
preserve its least model semantics. These transformations are based on
well-known transformation rules, such as unfolding and folding, guided by
suitable transformation strategies, such as specialization and generalization.
The objective of the transformations is to derive a new CLP program TransfT
where the predicate 'incorrect' is defined either by (i) the fact 'incorrect.'
(and in this case prog is not correct), or by (ii) the empty set of clauses
(and in this case prog is correct). In the case where we derive a CLP program
such that neither (i) nor (ii) holds, we iterate the transformation. Since the
problem is undecidable, this process may not terminate. We show through
examples that our method can be applied in a rather systematic way, and is
amenable to automation by transferring to the field of program verification
many techniques developed in the field of program transformation.Comment: In Proceedings Festschrift for Dave Schmidt, arXiv:1309.455
Correctness and completeness of logic programs
We discuss proving correctness and completeness of definite clause logic
programs. We propose a method for proving completeness, while for proving
correctness we employ a method which should be well known but is often
neglected. Also, we show how to prove completeness and correctness in the
presence of SLD-tree pruning, and point out that approximate specifications
simplify specifications and proofs.
We compare the proof methods to declarative diagnosis (algorithmic
debugging), showing that approximate specifications eliminate a major drawback
of the latter. We argue that our proof methods reflect natural declarative
thinking about programs, and that they can be used, formally or informally, in
every-day programming.Comment: 29 pages, 2 figures; with editorial modifications, small corrections
and extensions. arXiv admin note: text overlap with arXiv:1411.3015. Overlaps
explained in "Related Work" (p. 21
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