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|
A bibliography of papers that cite the Parma Polyhedra Library
and/or the works that defined the theory upon which it is based.
Copyright (C) 2001-2010 Roberto Bagnara <bagnara AT cs.unipr.it>
Copyright (C) 2010-2013 BUGSENG srl (http://bugseng.com)
This BibTeX database is made available under the Open Data Commons
Attribution License (ODC-By) v1.0, which is reproduced below for your
convenience and available at http://opendatacommons.org/licenses/by/1.0/
Summarizing:
- You are free: to copy, distribute and use the database; to produce
works from the database; to modify, transform and build upon the database.
- You must attribute any public use of the database, or works produced
from the database, in the manner specified in the license. For any
use or redistribution of the database, or works produced from it,
you must make clear to others the license of the database and keep
intact any notices on the original database.
@Inproceedings{AlbarghouthiG12,
Author = "A. Albarghouthi and A. Gurfinkel and M. Chechik",
Title = "Craig Interpretation",
Booktitle = "Static Analysis:
Proceedings of the 19th International Symposium",
Address = "Deauville, France",
Editor = "A. Min{'e} and D. Schmidt",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 7460,
Year = 2012,
ISBN = "978-3-642-33124-4 (Print) 978-3-642-33125-1 (Online)",
Pages = "300--316",
Abstract = "Abstract interpretation (AI) is one of the most scalable
automated approaches to program verification available
today. To achieve efficiency, many steps of the
analysis, e.g., joins and widening, lose precision. As a
result, AI often produces false alarms, coming from the
inability to find a safe inductive invariant even when
it exists in a chosen abstract domain.
To tackle this problem, we present Vinta, an iterative
algorithm that uses Craig interpolants to refine and
guide AI away from false alarms. Vinta is based on a
novel refinement strategy that capitalizes on recent
advances in SMT and interpolation-based verification to
(a) find counterexamples to justify alarms produced by
AI, and (b) to strengthen an invariant to exclude alarms
that cannot be justified. The refinement process
continues until either a safe inductive invariant is
computed, a counterexample is found, or resources are
exhausted. This strategy allows Vinta to recover
precision lost in many AI steps, and even to compute
inductive invariants that are inexpressible in the
chosen abstract domain (e.g., by adding disjunctions and
new terms).
We have implemented Vinta and compared it against top
verification tools from the recent software verification
competition. Our results show that Vinta outperforms
state-of-the-art verification tools."
}
@Inproceedings{AlbertACGPZ08,
Author = "E. Albert and P. Arenas and M. Codish and S. Genaim
and G. Puebla and D. Zanardini",
Title = "Termination Analysis of {Java} Bytecode",
Booktitle = "Proceedings of the 10th IFIP WG 6.1 International Conference
on Formal Methods for Open Object-Based Distributed Systems
(FMOODS 2008)",
Address = "Oslo, Norway",
Editor = "G. Barthe and F. S. de Boer",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 5051,
Year = 2008,
Pages = "2--18",
ISBN = "978-3-540-68862-4",
Abstract = "Termination analysis has received considerable
attention, traditionally in the context of declarative
programming, and recently also for imperative
languages. In existing approaches, termination is
performed on source programs. However, there are many
situations, including mobile code, where only the
compiled code is available. In this work we present an
automatic termination analysis for sequential Java
Bytecode programs. Such analysis presents all of the
challenges of analyzing a low-level language as well as
those introduced by object-oriented languages.
Interestingly, given a bytecode program, we produce a
\emph{constraint logic program}, CLP, whose termination
entails termination of the bytecode program. This allows
applying the large body of work in termination of CLP
programs to termination of Java bytecode. A prototype
analyzer is described and initial experimentation is
reported."
}
@Article{AlbertACGPZ12,
Author = "E. Albert and P. Arenas and S. Genaim and G. Puebla
and D. Zanardini",
Title = "Cost Analysis of Object-Oriented Bytecode Programs",
Journal = "Theoretical Computer Science",
Volume = 413,
Number = 1,
Pages = "142--159",
Year = 2012,
Note = "Quantitative Aspects of Programming Languages (QAPL 2010)",
ISSN = "0304-3975",
URL = "http://www.sciencedirect.com/science/article/pii/S0304397511006190",
Abstract = "Cost analysis statically approximates the cost of
programs in terms of their input data size. This paper
presents, to the best of our knowledge, the first
approach to the automatic cost analysis of
object-oriented bytecode programs. In languages such as
Java and C#, analyzing bytecode has a much wider
application area than analyzing source code since the
latter is often not available. Cost analysis in this
context has to consider, among others, dynamic dispatch,
jumps, the operand stack, and the heap. Our method takes
a bytecode program and a cost model specifying the
resource of interest, and generates cost relations which
approximate the execution cost of the program with
respect to such resource. We report on COSTA, an
implementation for Java bytecode which can obtain upper
bounds on cost for a large class of programs and
complexity classes. Our basic techniques can be directly
applied to infer cost relations for other
object-oriented imperative languages, not necessarily in
bytecode form."
}
@Inproceedings{AlbertAGP08,
Author = "E. Albert and P. Arenas and S. Genaim and G. Puebla",
Title = "Automatic Inference of Upper Bounds for Recurrence Relations
in Cost Analysis",
Booktitle = "Static Analysis:
Proceedings of the 15th International Symposium",
Address = "Valencia, Spain",
Editor = "M. Alpuente and G. Vidal",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 5079,
Year = 2008,
Pages = "221--237",
ISBN = "978-3-540-69163-1",
Abstract = "The classical approach to automatic cost analysis
consists of two phases. Given a program and some measure
of cost, we first produce \emph{recurrence relations}
(RRs) which capture the cost of our program in terms of
the size of its input data. Second, we convert such RRs
into \emph{closed form} (i.e., without
recurrences). Whereas the first phase has received
considerable attention, with a number of cost analyses
available for a variety of programming languages, the
second phase has received comparatively little
attention. In this paper we first study the features of
RRs generated by automatic cost analysis and discuss why
existing computer algebra systems are not appropriate
for automatically obtaining closed form solutions nor
upper bounds of them. Then we present, to our knowledge,
the first practical framework for the fully automatic
generation of reasonably accurate upper bounds of RRs
originating from cost analysis of a wide range of
programs. It is based on the inference of \emph{ranking
functions} and \emph{loop invariants} and on
\emph{partial evaluation}."
}
@Incollection{AlbertAGPZ08,
Author = "E. Albert and P. Arenas and S. Genaim
and G. Puebla and D. Zanardini",
Title = "{COSTA}: Design and Implementation of a Cost and Termination
Analyzer for {Java} Bytecode",
Booktitle = "Formal Methods for Components and Objects",
Editor = "Frank S. {de Boer} and M. M. Bonsangue
and S. Graf and W. P. {de Roever}",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Year = 2008,
Volume = 5382,
Pages = "113--132",
ISBN = "978-3-540-92187-5",
Note = "Revised papers presented at the 6th International Symposium on
Formal Methods for Components and Objects (FMCO 2007),
Amsterdam, The Netherlands, October 24--26, 2007",
Abstract = "This paper describes the architecture of COSTA, an
abstract interpretation based COST and termination
Analyzer for Java bytecode. The system receives as
input a bytecode program, (a choice of) a
\emph{resource} of interest and tries to obtain an upper
bound of the resource consumption of the program. COSTA
provides several non-trivial notions of cost, as the
consumption of the heap, the number of bytecode
instructions executed and the number of calls to a
specific method. Additionally, COSTA tries to prove
\emph{termination} of the bytecode program which implies
the boundedness of any resource consumption. Having cost
and termination together is interesting, as both
analyses share most of the machinery to, respectively,
infer cost \emph{upper bounds} and to prove that the
execution length is always \emph{finite} (i.e., the
program terminates). We report on experimental results
which show that COSTA can deal with programs of
realistic size and complexity, including programs which
use Java libraries. To the best of our knowledge, this
system provides for the first time evidence that
resource usage analysis can be applied to a realistic
object-oriented, bytecode programming language."
}
@Inproceedings{AlbertAPCFGGMPRRZ13,
Author = "E. Albert and D. E. Alonso-Blas and A. Puri
and J. Correas and A. Flores-Montoya and S. Genaim
and M. G{\'o}mez-Zamalloa and A. N. Masud and G. Puebla
and J. M. Rojas and G. Rom{\'a}n-D{\'i}ez and D. Zanardini",
Title = "Automatic Inference of Bounds on Resource Consumption",
Booktitle = "Formal Methods for Components and Objects:
Proceedings of the 11th International Symposium (FMCO 2012)",
Address = "Bertinoro, Italy",
Editor = "E. Giachino and R. H{\"a}hnle and F. S. de Boer and M. M. Bonsangue",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 7866,
Year = 2013,
Pages = "119--144",
ISBN = "978-3-642-40614-0 (Print) 978-3-642-40615-7 (Online)",
Abstract = "In this tutorial paper, we overview the techniques that
underlie the automatic inference of resource consumption
bounds. We first explain the basic techniques on a
Java-like sequential language. Then, we describe the
extensions that are required to apply our method on
concurrent ABS programs. Finally, we discuss some
advanced issues in resource analysis, including the
inference of non-cumulative resources and the treatment
of shared mutable data."
}
@Article{AlbertGM13,
Author = "E. Albert and S. Genaim and A. N. Masud",
Title = "On the Inference of Resource Usage Upper and Lower Bounds",
Journal = "ACM Transactions on Computational Logic",
Volume = 14,
Number = 3,
Year = 2013,
Abstract = "Cost analysis aims at determining the amount of
resources required to run a program in terms of its
input data sizes. The most challenging step is to infer
the cost of executing the loops in the program. This
requires bounding the number of iterations of each loop
and findig tight bounds for the cost of each of its
iterations. This article presents a novel approach to
infer upper and lower bounds from cost relations. These
relations are an extended form of standard recurrence
equations that can be nondeterministic, contain inexact
size constraints and have multiple arguments that
increase and/or decrease. We propose novel techniques to
automatically transform cost relations into worst-case
and best-case deterministic one-argument recurrence
relations. The solution of each recursive relation
provides a precise upper-bound and lower-bound for
executing a corresponding loop in the
program. Importantly, since the approach is developed at
the level of the cost equations, our techniques are
programming language independent."
}
@Inproceedings{AlonsoAG11,
Author = "D. Alonso and P. Arenas and S. Genaim",
Title = "Handling Non-linear Operations in the Value Analysis of {COSTA}",
Booktitle = "Proceedings of the 6th Workshop on Bytecode Semantics,
Verification, Analysis and Transformation (Bytecode 2011)",
Address = "Saarbrucken, Germany",
Series = "Electronic Notes in Theoretical Computer Science",
Publisher = "Elsevier Science B.V.",
Volume = 279,
Number = 1,
Pages = "3--17",
Year = 2011,
ISSN = "1571-0661",
Abstract = "Inferring precise relations between (the values of)
program variables at different program points is
essential for termination and resource usage
analysis. In both cases, this information is used to
synthesize ranking functions that imply the program's
termination and bound the number of iterations of its
loops. For efficiency, it is common to base value
analysis on non-disjunctive abstract domains such as
Polyhedra, Octagon, etc. While these domains are
efficient and able to infer complex relations for a wide
class of programs, they are often not sufficient for
modeling the effect of non-linear and bit arithmetic
operations. Modeling such operations precisely can be
done by using more sophisticated abstract domains, at
the price of performance overhead. In this paper we
report on the value analysis of COSTA that is based on
the idea of encoding the disjunctive nature of
non-linear operations into the (abstract) program
itself, instead of using more sophisticated abstract
domains. Our experiments demonstrate that COSTA is able
to prove termination and infer bounds on resource
consumption for programs that could not be handled
before."
}
@Inproceedings{AlthoffK12,
Author = "M. Althoff and B. H. Krogh",
Title = "Avoiding Geometric Intersection Operations
in Reachability Analysis of Hybrid Systems",
Booktitle = "Proceedings of the 15th ACM International Conference
on Hybrid Systems: Computation and Control (HSCC '12)",
Year = 2012,
ISBN = "978-1-4503-1220-2",
Address = "Beijing, China",
Pages = "45--54",
Publisher = "ACM Press, New York, USA",
Abstract = "Although a growing number of dynamical systems studied
in various fields are hybrid in nature, the verification
of properties, such as stability, safety, etc., is still
a challenging problem. Reachability analysis is one of
the promising methods for hybrid system verification,
which together with all other verification techniques
faces the challenge of making the analysis scale with
respect to the number of continuous state variables. The
bottleneck of many reachability analysis techniques for
hybrid systems is the geometrically computed
intersection with guard sets. In this work, we replace
the intersection operation by a nonlinear mapping onto
the guard, which is not only numerically stable, but
also scalable, making it possible to verify systems
which were previously out of reach. The approach can be
applied to the fairly common class of hybrid systems
with piecewise continuous solutions, guard sets modeled
as halfspaces, and urgent semantics, i.e. discrete
transitions are immediately taken when enabled by guard
sets. We demonstrate the usefulness of the new approach
by a mechanical system with backlash which has 101
continuous state variables."
}
@Inproceedings{Alur11,
Author = "R. Alur",
Title = "Formal Verification of Hybrid Systems",
Booktitle = "Proceedings of the 11th International Conference
on Embedded Software (EMSOFT 2011)",
Address = "Taipei, Taiwan",
Editor = "S. Chakraborty and A. Jerraya and S. K. Baruah
and S. Fischmeister",
Publisher = "ACM Press",
Year = 2011,
Pages = "273--278",
ISBN = "978-1-4503-0714-7",
Abstract = "In formal verification, a designer first constructs a
model, with mathematically precise semantics, of the
system under design, and performs extensive analysis
with respect to correctness requirements. The
appropriate mathematical model for embedded control
systems is hybrid systems that combines the traditional
state-machine based models for discrete control with
classical differential-equations based models for
continuously evolving physical activities. In this
article, we briefly review selected existing approaches
to formal verification of hybrid systems, along with
directions for future research."
}
@Inproceedings{AlurKRS08,
Author = "R. Alur and A. Kanade and S. Ramesh and K. Shashidhar",
Title = "Symbolic Analysis for Improving Simulation Coverage
of Simulink/Stateflow Models",
Booktitle = "Proceedings of the 8th ACM {\&} IEEE International Conference
on Embedded Software (EMSOFT 2008)",
Address = "Atlanta, Georgia, USA",
Editor = "L. {de Alfaro} and J. Palsberg",
Publisher = "ACM Press",
Pages = "89--98",
Year = 2008,
ISBN = "978-1-60558-468-3",
Abstract = "Aimed at verifying safety properties and improving
simulation coverage for hybrid systems models of
embedded controlsoftware, we propose a technique that
combines numerical simulation and symbolic methods for
computing state-sets. We consider systems with linear
dynamics described in the commercial modeling tool
Simulink/Stateflow. Given an initial state $x$,
and a discrete-time simulation trajectory, our
method computes a set of initial states that are
guaranteed to be equivalent to $x$, where two initial
states are considered to be equivalent if the resulting
simulation trajectories contain the same discrete
components at each step of the simulation. We illustrate
the benefits of our method on two case studies.
One case study is a benchmark proposed in the literature
for hybrid systems verification and another is a Simulink
demo model from Mathworks."
}
@Inproceedings{AmatoPS10,
Author = "G. Amato and M. Parton and F. Scozzari",
Title = "A Tool Which Mines Partial Execution Traces to Improve
Static Analysis",
Booktitle = "Proceedings of the 1st International Conference on
Runtime Verification (RV 2010)",
Address = "Balluta Bay, St Julians, Malta",
Series = "Lecture Notes in Computer Science",
Editor = "H. Barringer and Y. Falcone and B. Finkbeiner and K. Havelund
and I. Lee and G. Pace and G. Rosu and O. Sokolsky and
N. Tillmann",
Publisher = "Springer-Verlag, Berlin",
ISBN = "978-3-642-16611-2",
Pages = "475--479",
Volume = 6418,
Year = 2010,
Abstract = "We present a tool which performs abstract interpretation
based static analysis of numerical variables. The
novelty is that the analysis is parametric, and
parameters are chosen by applying a variant of principal
component analysis to partial execution traces of
programs."
}
@Article{AmatoPS12,
Author = "G. Amato and M. Parton and F. Scozzari",
Title = "Discovering Invariants via Simple Component Analysis",
Journal = "Journal of Symbolic Computation",
Publisher = "Elsevier Science B.V.",
Volume = 47,
Number = 12,
Year = 2012,
Pages = "1533--1560",
Abstract = "We propose a new technique combining dynamic and static
analysis of programs to find linear invariants. We use a
statistical tool, called simple component analysis, to
analyze partial execution traces of a given program. We
get a new coordinate system in the vector space of
program variables, which is used to specialize numerical
abstract domains. As an application, we instantiate our
technique to interval analysis of simple imperative
programs and show some experimental evaluations."
}
@Inproceedings{AmatoS12,
Author = "G. Amato and F. Scozzari",
Title = "Random: R-Based Analyzer for Numerical Domains",
Booktitle = "Proceedings of the 18th International Conference
on Logic for Programming, Artificial Intelligence,
and Reasoning (LPAR 2012)",
Address = "M\'erida, Venezuela",
Series = "Lecture Notes in Computer Science",
Editor = "N. Bj{\o}rner and A. Voronkov",
Publisher = "Springer-Verlag, Berlin",
ISBN = "978-3-642-28716-9",
Pages = "375--382",
Volume = 7180,
Year = 2012,
Abstract = "We present the tool Random (R-based Analyzer for
Numerical DOMains) for static analysis of imperative
programs. The tool is based on the theory of abstract
interpretation and implements several abstract
domains for detecting numerical properties, in
particular integer loop invariants. The tool
combines a statistical dynamic analysis with a static
analysis on the new domain of parallelotopes. The
tool has a graphical interface for tuning the
parameters of the analysis and visualizing partial
traces."
}
@Inproceedings{AmatoS13,
Author = "G. Amato and F. Scozzari",
Title = "Localizing Widening and Narrowing",
Booktitle = "Static Analysis:
Proceedings of the 20th International Symposium (SAS 2013)",
Address = "Seattle, USA",
Series = "Lecture Notes in Computer Science",
Editor = "F. Logozzo and M. F{\"a}hndrich",
Publisher = "Springer-Verlag, Berlin",
ISBN = "978-3-642-38855-2 (Print) 978-3-642-38856-9 (Online)",
Pages = "25--42",
Volume = 7935,
Year = 2013,
Abstract = "We show two strategies which may be easily applied to
standard abstract interpretation-based static
analyzers. They consist in 1) restricting the scope of
widening, and 2) intertwining the computation of
ascending and descending chains. Using these
optimizations it is possible to improve the precision of
the analysis, without any change to the abstract
domains."
}
@Inproceedings{Andre10,
Author = "{\'E}. Andr{\'e}",
Title = "{IMITATOR~II}:
A Tool for Solving the Good Parameters Problem in Timed Automata",
Booktitle = "Proceedings of the 12th International Workshop
on Verification of Infinite State Systems (INFINITY'10)",
Editor = "Y.-F. Chen and A. Rezine",
Address = "Singapore",
Pages = "91--99",
Series = "Electronic Proceedings in Theoretical Computer Science",
Volume = 39,
Year = 2010,
Abstract = "We present here \textsc{Imitator}~II, a new version of
\textsc{Imitator}, a tool implementing the ``inverse
method'' for parametric timed automata: given a reference
valuation of the parameters, it synthesizes a constraint
such that, for any valuation satisfying this constraint,
the system behaves the same as under the reference
valuation in terms of traces, i.e., alternating sequences
of locations and actions. \textsc{Imitator}~II also
implements the ``behavioral cartography algorithm'',
allowing us to solve the following good parameters
problem: find a set of valuations within a given bounded
parametric domain for which the system behaves well. We
present new features and optimizations of the tool, and
give results of applications to various examples of
asynchronous circuits and communication protocols."
}
@Techreport{AndreFS11TR,
Author = "{\'E}. Andr{\'e} and L. Fribourg and R. Soulat",
Title = "Enhancing the Inverse Method with State Merging",
Type = "Research report",
Number = "LSV-11-26",
Year = 2011,
Month = dec,
Institution = "Laboratoire Sp\'ecification \& V\'erification",
Address = "\'Ecole Normale Sup\'erieure de Cachan, Paris, France",
Abstract = "Keeping the state space small is essential when
verifying realtime systems using Timed Automata (TA). In
the model-checker Uppaal, the merging operation has been
used extensively in order to reduce the number of
states. Actually, Uppaal's merging technique applies
within the more general setting of Parametric Timed
Automata (PTA). The Inverse Method (IM) for a PTA A is a
procedure that synthesizes a zone around a given point
0 (parameter valuation) over which A is guaranteed to
behave similarly. We show that the integration of
merging into IM leads to the synthesis of larger zones
around 0. It also often improves the performance of
IM, both in terms of computational space and time, as
shown by our experimental results."
}
@Inproceedings{AndreFS12,
Author = "{\'E}. Andr{\'e} and L. Fribourg and R. Soulat",
Title = "Enhancing the Inverse Method with State Merging",
Booktitle = "NASA Formal Methods:
Proceedings of the 4th International Symposium (NFM 2012)",
Editor = "A. E. Goodloe and S. Person",
Address = "Norfolk, USA",
Pages = "381--396",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 7226,
Year = 2012,
Abstract = "Keeping the state space small is essential when
verifying realtime systems using Timed Automata (TA). In
the model-checker Uppaal, the merging operation has been
used extensively in order to reduce the number of
states. Actually, Uppaal's merging technique applies
within the more general setting of Parametric Timed
Automata (PTA). The Inverse Method (IM) for a PTA A is a
procedure that synthesizes a zone around a given point
0 (parameter valuation) over which A is guaranteed to
behave similarly. We show that the integration of
merging into IM leads to the synthesis of larger zones
around 0. It also often improves the performance of
IM, both in terms of computational space and time, as
shown by our experimental results."
}
@Inproceedings{AndreFS13,
Author = "{\'E}. Andr{\'e} and L. Fribourg and R. Soulat",
Title = "Merge and Conquer: State Merging in Parametric Timed Automata",
Booktitle = "Automated Technology for Verification and Analysis:
Proceedings of the 11th International Symposium (ATVA 2013)",
Editor = "D. Van Hung and M. Ogawa",
Address = "Hanoi, Vietnam",
Pages = "381--396",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 8172,
Year = 2013,
Abstract = "Parameter synthesis for real-time systems aims at
synthesizing dense sets of valuations for the timing
requirements, guaranteeing a good behavior. A popular
formalism for modeling parameterized real-time systems
is parametric timed automata (PTAs). Compacting the
state space of PTAs as much as possible is
fundamental. We present here a state merging reduction
based on convex union, that reduces the state space, but
yields an over-approximation of the executable
paths. However, we show that it preserves the sets of
reachable locations and executable actions. We also show
that our merging technique associated with the inverse
method, an algorithm for parameter synthesis, preserves
locations as well, and outputs larger sets of parameter
valuations."
}
@Inproceedings{AndreLSDL13,
Author = "E. Andr{\'e} and Y. Liu and J. Sun and J. S. Dong and {S.-W}. Lin",
Title = "PSyHCoS: Parameter Synthesis for Hierarchical Concurrent
Real-Time Systems",
Booktitle = "Computer Aided Verification:
Proceedings of the 25th International Conference (CAV 2013)",
Year = 2013,
Pages = "984--989",
Editor = "N. Sharygina and H. Veith",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 8044,
ISBN = "978-3-642-39798-1",
Abstract = "Real-time systems are often hard to control, due to
their complicated structures, quantitative time factors
and even unknown delays. We present here PSyHCoS, a
tool for analyzing parametric real-time systems
specied using the hierarchical modeling language
PSTCSP. PSyHCoS supports several algorithms for
parameter synthesis and model checking, as well as state
space reduction techniques. Its architecture favors
reusability in terms of syntax, semantics, and
algorithms. It comes with a friendly user interface that
can be used to edit, simulate and verify PSTCSP
models. Experiments show its eciency and
applicability."
}
@Book{AndreS13,
Author = "{\'E}. Andr{\'e} and R. Soulat",
Title = "The Inverse
Method: Parametric Verification of Real-time Embedded Systems",
Publisher = "John Wiley and Sons.",
Series = "{FOCUS Series}",
ISBN = "9781118569405",
Year = 2013,
Abstract = "This book introduces state-of-the-art verification
techniques for real-time embedded systems, based on the
inverse method for parametric timed automata. It reviews
popular formalisms for the specification and
verification of timed concurrent systems and, in
particular, timed automata as well as several extensions
such as timed automata equipped with stopwatches, linear
hybrid automata and affine hybrid automata. The inverse
method is introduced, and its benefits for guaranteeing
robustness in real-time systems are shown. Then, it is
shown how an iteration of the inverse method can solve
the good parameters problem for parametric timed
automata by computing a behavioral cartography of the
system. Different extensions are proposed particularly
for hybrid systems and applications to scheduling
problems using timed automata with stopwatches. Various
examples, both from the literature and industry,
illustrate the techniques throughout the book. Various
parametric verifications are performed, in particular of
abstractions of a memory circuit sold by the chipset
manufacturer ST-Microelectronics, as well as of the
prospective flight control system of the next generation
of spacecraft designed by ASTRIUM Space Transportation."
}
@Inproceedings{ArmandoBM07,
Author = "A. Armando and M. Benerecetti and J. Mantovani",
Title = "Abstraction Refinement of Linear Programs with Arrays",
Booktitle = "Proceedings of the 13th International Conference on
Tools and Algorithms for the Construction and Analysis
of Systems (TACAS 2007)",
Address = "Braga, Portugal",
Editor = "O. Grumberg and M. Huth",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 4424,
Pages = "373--388",
Year = 2007,
ISBN = "3-540-71208-4",
Abstract = "In previous work we presented a model checking procedure
for linear programs, i.e. programs in which variables
range over a numeric domain and expressions involve
linear combinations of the variables. In this paper we
lift our model checking procedure for linear programs to
deal with arrays via iterative abstraction
refinement. While most approaches are based on predicate
abstraction and therefore the abstraction is relative to
sets of predicates, in our approach the abstraction is
relative to sets of variables and array indexes, and the
abstract program can express complex correlations
between program variables and array elements. Thus,
while arrays are problematic for most of the approaches
based on predicate abstraction, our approach treats them
in a precise way. This is an important feature as arrays
are ubiquitous in programming. We provide a detailed
account of both the abstraction and the refinement
processes, discuss their implementation in the eureka
tool, and present experimental results that confirm the
effectiveness of our approach on a number of programs of
interest."
}
@Inproceedings{AsarinDFGLGM06,
Author = "E. Asarin and T. Dang and G. Frehse and A. Girard
and C. {Le Guernic} and O. Maler",
Title = "Recent Progress in Continuous and Hybrid Reachability Analysis",
Booktitle = "Proceedings of the IEEE International Symposium
on Computer-Aided Control Systems Design",
Address = "Technische Universit{\"a}t M{\"u}nchen, Munich, Germany",
Year = 2006,
Abstract = "Set-based reachability analysis computes all possible
states a system may attain, and in this sense provides
knowledge about the system with a completeness, or
coverage, that a finite number of simulation runs can
not deliver. Due to its inherent complexity, the
application of reachability analysis has been limited so
far to simple systems, both in the continuous and the
hybrid domain. In this paper we present recent advances
that, in combination, significantly improve this
applicability, and allow us to find better balance
between computational cost and accuracy. The
presentation covers, in a unified manner, a variety of
methods handling increasingly complex types of
continuous dynamics (constant derivative, linear,
nonlinear). The improvements include new geometrical
objects for representing sets, new approximation
schemes, and more flexible combinations of graph-search
algorithm and partition refinement. We report briefly
some preliminary experiments that have enabled the
analysis of systems previously beyond reach."
}
@Inproceedings{Avery06,
Author = "J. Avery",
Title = "Size-Change Termination and Bound Analysis",
Booktitle = "Proceedings of the 8th International Symposium
on Functional and Logic Programming (FLOPS 2006)",
Address = "Fuji-Susono, Japan",
Editor = "M. Hagiya and P. Wadler",
Pages = "192--207",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 3945,
Year = 2006,
ISBN = "3-540-33438-6",
Abstract = "Despite its simplicity, the size-change termination
principle, presented by Lee, Jones and Ben-Amram in
[LJB01], is surprisingly strong and is able to show
termination for a large class of programs. A significant
limitation for its use, however, is the fact that the
SCT requires data types to be well-founded, and that all
mechanisms used to determine termination must involve
decreases in these global, well-founded partial orders.
Following is an extension of the size-change principle
that allows for non-well founded data types, and a
realization of this principle for integer data
types. The extended size-change principle is realized
through combining abstract interpretation over the
domain of convex polyhedra with the use of size-change
graphs. In the cases when data types \emph{are} well
founded, the method handles every case that is handled
by LJB size-change termination. The method has been
implemented in a subject language independent shared
library, \texttt{libesct} (available at [Ave05a]), as
well as for the ANSI C specializer
$\texttt{C-Mix}_\texttt{II}$, handling a
subset of its internal language \texttt{Core-C}."
}
@Inproceedings{BagnaraR-CZ05,
Author = "R. Bagnara and E. Rodr{\'\i}guez-Carbonell and E. Zaffanella",
Title = "Generation of Basic Semi-algebraic Invariants
Using Convex Polyhedra",
Booktitle = "Static Analysis:
Proceedings of the 12th International Symposium",
Address = "London, UK",
Editor = "C. Hankin and I. Siveroni",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 3672,
ISBN = "3-540-28584-9",
Year = 2005,
Pages = "19--34",
Abstract = "A technique for generating invariant polynomial
\emph{inequalities} of bounded degree is presented using
the abstract interpretation framework. It is based on
overapproximating basic semi-algebraic sets, i.e., sets
defined by conjunctions of polynomial inequalities, by
means of convex polyhedra. While improving on the
existing methods for generating invariant polynomial
\emph{equalities}, since polynomial inequalities are
allowed in the guards of the transition system, the
approach does not suffer from the prohibitive complexity
of the methods based on quantifier-elimination. The
application of our implementation to benchmark programs
shows that the method produces non-trivial invariants in
reasonable time. In some cases the generated invariants
are essential to verify safety properties that cannot be
proved with classical linear invariants."
}
@Techreport{BagnaraR-CZ05TR,
Author = "R. Bagnara and E. Rodr{\'\i}guez-Carbonell and E. Zaffanella",
Title = "Generation of Basic Semi-algebraic Invariants
Using Convex Polyhedra",
Number = "LSI-05-14-R",
Type = "Report de recerca",
Institution = "Departament de Llenguatges i Sistemes Inform{\`a}tics,
Universitat Polit{\`e}cnica de Catalunya, Barcelona, Spain",
Year = 2005,
Note = "Available at \url{http://www.lsi.upc.edu/dept/techreps/techreps.html}"
}
@Incollection{BandaG09,
Author = "G. Banda and J. P. Gallagher",
Title = "Analysis of Linear Hybrid Systems in {CLP}",
Booktitle = "Logic-Based Program Synthesis and Transformation",
Editor = "M. Hanus",
Pages = "55--70",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 5438,
Year = 2009,
ISBN = "978-3-642-00514-5",
Note = "Revised selected papers presented at the 18th International
Symposium on Logic-Based Program Synthesis and Transformation
(LOPSTR 2008), Valencia, Spain, July 17--18, 2008",
Abstract = "In this paper we present a procedure for representing
the semantics of linear hybrid automata (LHAs) as
constraint logic programs (CLP); flexible and accurate
analysis and verification of LHAs can then be performed
using generic CLP analysis and transformation
tools. LHAs provide an expressive notation for
specifying real-time systems. The main contributions are
(i) a technique for capturing the reachable states of
the continuously changing state variables of the LHA as
CLP constraints; (ii) a way of representing events in
the LHA as constraints in CLP, along with a product
construction on the CLP representation including
synchronisation on shared events; (iii) a framework in
which various kinds of reasoning about an LHA can be
flexibly performed by combining standard CLP
transformation and analysis techniques. We give
experimental results to support the usefulness of the
approach and argue that we contribute to the general
field of using static analysis tools for verification."
}
@Inproceedings{Ben-AmramG13,
Author = "A. M. Ben-Amram and S. Genaim",
Title = "On the Linear Ranking Problem for Integer Linear-Constraint Loops",
Booktitle = "Proceedings of the 40th Annual ACM SIGPLAN-SIGACT Symposium on
Principles of Programming Languages (POPL 2013)",
Year = 2013,
ISBN = "978-1-4503-1832-7",
Address = "Rome, Italy",
Pages = "51--62",
Publisher = "ACM Press",
Note = "Also published in ACM SIGPLAN Notices, POPL '13, Volume 48, Issue 1",
Abstract = "In this paper we study the complexity of the Linear
Ranking problem: given a loop, described by linear
constraints over a finite set of integer variables, is
there a linear ranking function for this loop? While
existence of such a function implies termination, this
problem is not equivalent to termination. When the
variables range over the rationals or reals, the Linear
Ranking problem is known to be PTIME decidable. However,
when they range over the integers, whether for
single-path or multipath loops, the complexity of the
Linear Ranking problem has not yet been determined. We
show that it is coNP-complete. However, we point out some
special cases of importance of PTIME complexity. We also
present complete algorithms for synthesizing linear
ranking functions, both for the general case and the
special PTIME cases."
}
@Inproceedings{BerendsenJV10,
Author = "J. Berendsen and D. N. Jansen and F. W. Vaandrager",
Title = "Fortuna: Model Checking Priced Probabilistic Timed Automata",
Booktitle = "Proceedings of the 7th International Conference on the
Quantitative Evaluation of Systems (QEST 2010)",
Address = "Williamsburg, Virginia, USA",
Publisher = "IEEE Computer Society",
Year = 2010,
Pages = "273--281",
ISBN = "978-0-7695-4188-4",
Abstract = "Fortuna is the first tool for model checking priced
probabilistic timed automata (PPTAs). PPTAs are an
important model that can handle the combination of
real-time, probabilistic and cost features. Only model
checkers that incorporate all these features can
address the key design trade-offs that arise in many
practical applications such as: the Zeroconf,
Bluetooth, IEEE802.11 and Firewire protocols, protocols
for sensor networks, and scheduling problems with
failures. PPTAs are an extension of probabilistic timed
automata (PTAs), by having cost-rates and discrete cost
increments on states. Fortuna is able to compute the
maximal probability by which a class of states can be
reached under a certain cost-bound (and time bound.)
Although the problem is undecidable in general, there
exists a semi-algorithm that produces a non-decreasing
sequence of maximal probabilities. This paper enhances
that algorithm. We compared the performance of Fortuna
with existing approaches for PTAs. Surprisingly,
although PPTAs are more general, our techniques exhibit
superior performance.",
}
@TechReport{BeyL11TR,
Author = "A. Bey S. Leue",
Title = "Modeling and Analyzing Spike Timing Dependent Plasticity
with Linear Hybrid Automata",
Number = "soft-11-03",
Institution = "University of Konstanz, Germany",
Year = 2011,
Month = may,
Abstract = "We propose a model for synaptic plasticity according to
the Spike Timing Dependent Plasticity (STDP) theory
using Linear Hybrid Au- tomata (LHA). We first present a
compositional LHA model in which each component
corresponds to some process in STDP. We then ab- stract
this model into a monolithic LHA model in order to
enable formal analysis using hybrid model checking. We
discuss how the avail- ability of an LHA model as well
as its formal analysis using the tool PHAVer can support
a better understanding of the dynamics of STDP."
}
@Inproceedings{BeyerG11,
Author = "M. Beyer and S. Glesner",
Title = "Static Run-Time Mode Extraction by State Partitioning
in Synchronous Process Networks",
Booktitle = "Proceedings of the 14th International Workshop on
Software and Compilers for Embedded Systems (SCOPES 2011)",
Year = 2011,
ISBN = "978-1-4503-0763-5",
Pages = "28--37",
URL = "http://doi.acm.org/10.1145/1988932.1988938",
Publisher = "ACM Press",
Address = "New York, NY, USA",
Abstract = "Process Networks (PNs) are used for modeling
streaming-oriented applications with changing behavior,
which must be mapped on a concurrent architecture to
meet the performance and energy constraints of embedded
devices. Finding an optimal mapping of Process Networks
to the constrained architecture presumes that the
behavior of the PN is statically known. In this paper we
present a static analysis for synchronous PNs that
partitions the state space according to extract run-time
modes based on a Data Augmented Control Flow Automaton
(DACFA). The result is a mode automaton whose nodes
describe identified program modes and whose edges
represent transitions among them. Optimizing back-ends
mapping from PNs to concurrent architectures can be
guided by these analysis results."
}
@Inproceedings{BeyerG12,
Author = "M. Beyer and S. Glesner",
Title = "Static Analysis of Run-Time Modes in Synchronous Process Network",
Booktitle = "Perspectives of Systems Informatics: Proceedings of the
8th International Andrei Ershov Memorial Conference",
Series = "Lecture Notes in Computer Science",
Editor = "E. Clarke and I. Virbitskaite and A. Voronkov",
Publisher = "Springer-Verlag, Berlin",
ISBN = "978-3-642-29708-3",
Pages = "55--67",
Volume = 7162,
Year = 2012,
Abstract = "For modeling modern streaming-oriented applications,
Process Networks (PNs) are used to describe systems with
changing behavior, which must be mapped on a concurrent
architecture to meet the performance and energy
constraints of embedded devices. Finding an optimal
mapping of Process Networks to the constrained
architecture presumes that the behavior of the Process
Network is statically known. In this paper we present a
static analysis for synchronous PNs that extracts
different run-time modes by using polyhedral
abstraction. The result is a Mealy machine whose states
describe different run-time modes and the edges among
them represent transitions. This machine can be used to
guide optimizing backend mappings from PNs to concurrent
architectures."
}
@Inproceedings{BouchyFL08,
Author = "F. Bouchy and A. Finkel and J. Leroux",
Title = "Decomposition of Decidable First-Order Logics
over Integers and Reals",
Booktitle = "Proceedings of the 15th International Symposium on
Temporal Representation and Reasoning (TIME '08)",
Address = "Montreal, Canada",
Publisher = "IEEE Computer Society Press",
Pages = "147--155",
Year = 2008,
Abstract = "We tackle the issue of representing infinite sets of
real-valued vectors. This paper introduces an
operator for combining integer and real sets. Using
this operator, we decompose three well-known logics
extending Presburger with reals. Our decomposition
splits a logic into two parts : one integer, and one
decimal (i.e. on the interval $[0, 1[$). We also give
a basis for an implementation of our representation."
}
@Inproceedings{BozgaGI09,
Author = "M. Bozga and C. G\^{\i}rlea and R. Iosif",
Title = "Iterating Octagons",
Booktitle = "Proceedings of the 15th International Conference on
Tools and Algorithms for the Construction and Analysis
of Systems (TACAS 2009)",
Address = "York, UK",
Editor = "S. Kowalewski and A. Philippou",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 5505,
Pages = "337-351",
Year = 2009,
ISBN = "978-3-642-00767-5",
Abstract = "In this paper we prove that the transitive closure of a
nondeterministic octagonal relation using integer
counters can be expressed in Presburger arithmetic. The
direct consequence of this fact is that the reachability
problem is decidable for flat counter automata with
octagonal transition relations. This result improves the
previous results of Comon and Jurski [Hubert Comon and
Yan Jurski. Multiple counters automata, safety analysis
and presburger arithmetic. In \emph{CAV}, LNCS 1427, pages
268-279, 1998] and Bozga, Iosif and Lakhnech [Marius Bozga,
Radu Iosif, and Yassine Lakhnech. Flat parametric counter
automata. In \emph{ICALP}, LNCS 4052, pages 577-588.
Springer-Verlag, 2006] concerning the computation of
transitive closures for difference bound relations.
The importance of this result is justified by the wide
use of octagons to computing sound abstractions of
real-life systems [A. Min\'e. The octagon abstract domain.
\emph{Higher-Order and Symbolic Computation}, 19(1):31-100,
2006]. We have implemented the octagonal transitive closure
algorithm in a prototype system for the analysis of counter
automata, called FLATA, and we have experimented with a
number of test cases."
}
@Inproceedings{BramanM08,
Title = "Safety Verification of Fault Tolerant Goal-based Control Programs
with Estimation Uncertainty",
Author = "J. M. B. Braman and R. M. Murray",
Booktitle = "Proceedings of the 2008 American Control Conference",
Address = "Seattle, Washington, USA",
Publisher = "IEEE Press",
Year = 2008,
Pages = "27--32",
ISSN = "0743-1619",
ISBN = "978-1-4244-2078-0",
Abstract = "Fault tolerance and safety verification of control
systems that have state variable estimation uncertainty
are essential for the success of autonomous robotic
systems. A software control architecture called mission
data system, developed at the Jet Propulsion Laboratory,
uses goal networks as the control program for autonomous
systems. Certain types of goal networks can be converted
into linear hybrid systems and verified for safety using
existing symbolic model checking software. A process for
calculating the probability of failure of certain
classes of verifiable goal networks due to state
estimation uncertainty is presented. A verifiable
example task is presented and the failure probability of
the control program based on estimation uncertainty is
found."
}
@Techreport{Braun12TR,
Author = "V. Braun",
Title = "Counting Points and {Hilbert} Series in String Theory",
Institution = "University of Pennsylvania in Philadelphia, USA",
Number = "arXiv:1206.2236v1 [hep-th]",
Note = "Available from \url{http://arxiv.org/}",
Year = 2012,
Month = jun,
URL = "http://arxiv.org/abs/1206.2236v1",
Abstract = "The problem of counting points is revisited from the
perspective of reflexive 4-dimensional polytopes. As an
application, the Hilbert series of the 473,800,776
reflexive polytopes (equivalently, their Calabi-Yau
hypersurfaces) are computed."
}
@Inproceedings{BrihayeDGQRW13,
Author = "T. Brihaye and L. Doyen and G. Geeraerts and J. Ouaknine and J.-F. Raskin and J. Worrell",
Title = "Time-Bounded Reachability for Monotonic Hybrid Automata: Complexity and Fixed Points",
Booktitle = "Automated Technology for Verification and Analysis:
Proceedings of the 11th International Symposium (ATVA 2013)",
Address = "Hanoi, Vietnam",
Editor = "Dang Van Hung",
Year = 2013,
Pages = "55--70",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 8172,
ISBN = "978-3-319-02443-1",
Abstract = "We study the time-bounded reachability problem for
monotonic hybrid automata (MHA), i.e., rectangular
hybrid automata for which the rate of each variable is
either always non-negative or always non-positive. In
this paper, we revisit the decidability results
presented in [T.~Brihaye and L.~Doyen and G.~Geeraerts
and J.~Ouaknine. and J.-F.~Raskin and J.~Worrell: On
reachability for hybrid automata over bounded time. In:
ICALP 2011, Part II. LNCS, vol. 6756,
pp. 416–427. Springer, Heidelberg (2011)] and show that
the problem is NExpTime-complete. We also show that we
can effectively compute fixed points that characterise
the sets of states that are reachable
(resp. co-reachable) within T time units from a given
state."
}
@Techreport{CacheraM-A05,
Author = "D. Cachera and K. Morin-Allory",
Title = "Proving Parameterized Systems: The Use of a Widening Operator
and Pseudo-Pipelines in Polyhedral Logic",
Type = "Research Report",
Number = "ISRN TIMA--RR-05/04-01--FR",
Institution = "TIMA Laboratory",
Address = "Grenoble, France",
Year = 2005,
Abstract = "We propose proof techniques and tools for the formal
verification of regular parameterized systems. These
systems are expressed in the polyhedral model, which
combines affine recurrence equations with index sets of
polyhedral shape. We extend a previously defined proof
system based on a polyhedral logic with the detection of
pseudo-pipelines, that are particular patterns in the
variable definitions generalizing the notion of
pipeline. The combination of pseudo-pipeline detection
with the use of a simple widening operator greatly
improves the effectiveness of our proof techniques."
}
@Article{CarloniPPS-V06,
Author = "L. P. Carloni and R. Passerone and A. Pinto
and A. L. Sangiovanni-Vincentelli",
Title = "Languages and Tools for Hybrid Systems Design",
Journal = "Foundations and Trends. in Electronic Design Automation",
Volume = 1,
Number = "1/2",
Pages = "1--193",
Year = 2006,
Abstract = "The explosive growth of embedded electronics is bringing
information and control systems of increasing complexity
to every aspects of our lives. The most challenging
designs are safety-critical systems, such as
transportation systems (e.g., airplanes, cars, and
trains), industrial plants and health care
monitoring. The difficulties reside in accommodating
constraints both on functionality and
implementation. The correct behavior must be guaranteed
under diverse states of the environment and potential
failures; implementation has to meet cost, size, and
power consumption requirements. The design is therefore
subject to extensive mathematical analysis and
simulation. However, traditional models of information
systems do not interface well to the continuous evolving
nature of the environment in which these devices
operate. Thus, in practice, different mathematical
representations have to be mixed to analyze the overall
behavior of the system. \emph{Hybrid systems} are a
particular class of mixed models that focus on the
combination of discrete and continuous subsystems. There
is a wealth of tools and languages that have been
proposed over the years to handle hybrid
systems. However, each tool makes different assumptions
on the environment, resulting in somewhat different
notions of hybrid system. This makes it difficult to
share information among tools. Thus, the community
cannot maximally leverage the substantial amount of work
that has been directed to this important topic. In this
paper, we review and compare hybrid system tools by
highlighting their differences in terms of their
underlying semantics, expressive power and mathematical
mechanisms. We conclude our review with a comparative
summary, which suggests the need for a unifying approach
to hybrid systems design. As a step in this direction,
we make the case for a \emph{semantic-aware interchange
format}, which would enable the use of joint techniques,
make a formal comparison between different approaches
possible, and facilitate exporting and importing design
representations."
}
@Inproceedings{CarnevaliPSV13,
Author = "L. Carnevali and M. Paolieri and A. Santoni and E. Vicario",
Title = "Non-Markovian Analysis for Model Driven Engineering of Real-time Software",
Booktitle = "Proceedings of the 4th ACM/SPEC International Conference
on Performance Engineering (ICPE '13)",
Year = 2013,
ISBN = "978-1-4503-1636-1",
Address = "Prague, Czech Republic",
Pages = "113--124",
Publisher = "ACM, New York, USA",
Abstract = "Quantitative evaluation of models with stochastic timings
can decisively support schedulability analysis and
performance engineering of real-time concurrent
systems. These tasks require modeling formalisms and
solution techniques that can encompass stochastic
temporal parameters firmly constrained within a bounded
support, thus breaking the limits of Markovian
approaches. The problem is further exacerbated by the
need to represent suspension of timers, which results
from common patterns of real-time programming. This poses
relevant challenges both in the theoretical development
of non-Markovian solution techniques and in their
practical integration within a viable tailoring of
industrial processes.
We address both issues by extending a method for
transient analysis of non-Markovian models to encompass
suspension of timers. The solution technique addresses
models that include timers with bounded and deterministic
support, which are essential to represent synchronous
task releases, timeouts, offsets, jitters, and
computations constrained by a Best Case Execution Time
(BCET) and a Worst Case Execution Time (WCET). As a
notable trait, the theory of analysis is amenable to the
integration within a Model Driven Development (MDD)
approach, providing specific evaluation capabilities in
support of performance engineering without disrupting the
flow of design and documentation of the consolidated
practice.",
}
@Inproceedings{ChakarovS13,
Author = "A. Chakarov and S. Sankaranarayanan",
Title = "Probabilistic Program Analysis with Martingales",
Booktitle = "Computer Aided Verification:
Proceedings of the 25th International Conference (CAV 2013)",
Year = 2013,
Pages = "511-526",
Editor = "N. Sharygina and H. Veith",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 8044,
ISBN = "978-3-642-39798-1",
Abstract = "We present techniques for the analysis of infinite state
probabilistic programs to synthesize probabilistic
invariants and prove almost-sure termination. Our
analysis is based on the notion of (super) martingales
from probability theory. First, we define the concept of
(super) martingales for loops in probabilistic
programs. Next, we present the use of concentration of
measure inequalities to bound the values of martingales
with high probability. This directly allows us to infer
probabilistic bounds on assertions involving the program
variables. Next, we present the notion of a super
martingale ranking function (SMRF) to prove almost sure
termination of probabilistic programs. Finally, we
extend constraint-based techniques to synthesize
martingales and super-martingale ranking functions for
probabilistic programs. We present some applications of
our approach to reason about invariance and termination
of small but complex probabilistic programs."
}
@Article{ChakrabortyMS06,
Title = "Reasoning about Synchronization in {GALS} Systems",
Author = "S. Chakraborty and J. Mekie and D. K. Sharma",
Journal = "Formal Methods in System Design",
Publisher = "Springer Netherlands",
Volume = 28,
Number = 2,
Pages = "153--169",
Year = 2006,
Abstract = "Correct design of interface circuits is crucial for the
development of System-on-Chips (SoC) using off-the-shelf
IP cores. For correct operation, an interface circuit
must meet strict synchronization timing constraints, and
also respect sequencing constraints between events
dictated by interfacing protocols and rational clock
relations. In this paper, we propose a technique for
automatically analyzing the interaction between
independently specified synchronization constraints and
sequencing constraints between events. We show how this
analysis can be used to derive delay constraints for
correct operation of interface circuits in a GALS
system. Our methodology allows an SoC designer to mix
and match different interfacing protocols, rational
clock relations and synchronization constraints for
communication between a pair of modules, and
automatically explore their implications on correct
interface circuit design."
}
@Inproceedings{ChenMC08,
Author = "L. Chen and A. Min{\'e} and P. Cousot",
Title = "A Sound Floating-Point Polyhedra Abstract Domain",
Booktitle = "Proceedings of the 6th Asian Symposium on
Programming Languages and Systems (APLAS 2008)",
Address = "Bangalore, India",
Editor = "G. Ramalingam",
Year = 2008,
Pages = "3--18",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 5356,
ISBN = "978-3-540-89329-5",
Abstract = "The polyhedra abstract domain is one of the most
powerful and commonly used numerical abstract domains in
the field of static program analysis based on abstract
interpretation. In this paper, we present an
implementation of the polyhedra domain using
floating-point arithmetic without sacrificing soundness.
Floating-point arithmetic allows a compact memory
representation and an efficient implementation on
current hardware, at the cost of some loss of precision
due to rounding. Our domain is based on a
constraint-only representation and employs sound
floating-point variants of Fourier-Motzkin elimination
and linear programming. The preliminary experimental
results of our prototype are encouraging. To our
knowledge, this is the first time that the polyhedra
domain is adapted to floating-point arithmetic in a
sound way."
}
@Inproceedings{ChenKSW13,
Author = "T. Chen and M. Kwiatkowska and A. Simaitis and C. Wiltsche",
Title = "Synthesis for Multi-Objective Stochastic Games:
An Application to Autonomous Urban Driving",
Booktitle = "Quantitative Evaluation of Systems:
Proceedings of the 10th International Conference (QEST 2013)",
Address = "Buenos Aires, Argentina",
Editor = "K. Joshi and M. Siegle and M. Stoelinga and P. R. D’Argenio",
Year = 2013,
Pages = "322--337",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 8054,
ISBN = "978-3-642-40195-4 (Print) 978-3-642-40196-1 (Online)",
Abstract = "We study strategy synthesis for stochastic two-player
games with multiple objectives expressed as a
conjunction of LTL and expected total reward goals. For
stopping games, the strategies are constructed from the
Pareto frontiers that we compute via value
iteration. Since, in general, infinite memory is
required for deterministic winning strategies in such
games, our construction takes advantage of randomised
memory updates in order to provide compact
strategies. We implement our methods in PRISM-games, a
model checker for stochastic multi-player games, and
present a case study motivated by the DARPA Urban
Challenge, illustrating how our methods can be used to
synthesise strategies for high-level control of
autonomous vehicles."
}
@Inproceedings{ColonS11,
Author = "M. Col{\'o}n and S. Sankaranarayanan",
Title = "Generalizing the Template Polyhedral Domain",
Booktitle = "Proceedings of the 20th European Symposium on Programming
(ESOP 2011)",
Address = "Saarbr{\"u}cken, Germany",
Series = "Lecture Notes in Computer Science",
Editor = "G. Barthe",
Publisher = "Springer-Verlag, Berlin",
ISBN = "978-3-642-19717-8",
Pages = "176--195",
Volume = 6602,
Year = 2011,
Abstract = "Template polyhedra generalize weakly relational domains
by specifying arbitrary fixed linear expressions on the
left-hand sides of inequalities and undetermined
constants on the right. The domain operations required
for analysis over template polyhedra can be computed in
polynomial time using linear programming. In this paper,
we introduce the generalized template polyhedral domain
that extends template polyhedra using fixed left-hand
side expressions with bilinear forms involving program
variables and unknown parameters to the right. We prove
that the domain operations over generalized templates
can be defined as the ``best possible abstractions'' of
the corresponding polyhedral domain operations. The
resulting analysis can straddle the entire space of
linear relation analysis starting from the template
domain to the full polyhedral domain. We show that
analysis in the generalized template domain can be
performed by dualizing the join, post-condition and
widening operations. We also investigate the special
case of template polyhedra wherein each bilinear form
has at most two parameters. For this domain, we use the
special properties of two dimensional polyhedra and
techniques from fractional linear programming to derive
domain operations that can be implemented in polynomial
time over the number of variables in the program and the
size of the polyhedra. We present applications of
generalized template polyhedra to strengthen previously
obtained invariants by converting them into
templates. We describe an experimental evaluation of an
implementation over several benchmark systems."
}
@Inproceedings{CovaFBV06,
Author = "M. Cova and V. Felmetsger and G. Banks and G. Vigna",
Title = "Static Detection of Vulnerabilities in x86 Executables",
Booktitle = "Proceedings of the 22nd Annual Computer Security Applications
Conference (ACSAC 22)",
Address = "Miami, Florida, USA",
Publisher = "IEEE Computer Society Press",
Pages = "269--278",
Year = 2006,
Abstract = "In the last few years, several approaches have been
proposed to perform vulnerability analysis of
applications written in high-level languages. However,
little has been done to automatically identify
security-relevant flaws in binary code.
In this paper, we present a novel approach to the
identification of vulnerabilities in x86 executables in
ELF binary format. Our approach is based on static
analysis and symbolic execution techniques. We
implemented our approach in a proof-of-concept tool and
used it to detect taint-style vulnerabilities in binary
code. The results of our evaluation show that our
approach is both practical and effective."
}
@Article{DangT12,
Author = "T. Dang and R. Testylier",
Title = "Reachability Analysis for Polynomial Dynamical Systems Using the Bernstein Expansion",
Journal = "Reliable Computing",
Publisher = "Kluwer Academic Publishers",
Volume = 17,
Number = 2,
Year = 2012,
ISSN = "1573-1340",
Pages = "128--152",
Abstract = "This paper is concerned with the reachability
computation problem for polynomial discrete-time
dynamical systems. Such computations con- stitute a
crucial component in algorithmic verication tools for
hybrid systems and embedded software with polynomial
dynamics, which have found applications in many
engineering domains. We describe two meth- ods for
over-approximating the reachable sets of such systems;
these meth- ods are based on a combination of the
Bernstein expansion of polynomial functions and a
representation of reachable sets by template polyhedra.
Using a prototype implementation, the performance of the
methods was demonstrated on a number of examples of
control systems and biological systems."
}
@Inproceedings{DenmatGD07,
Author = "T. Denmat and A. Gotlieb and M. Ducass{\'e}",
Title = "An Abstract Interpretation Based Combinator for Modelling
While Loops in Constraint Programming",
Booktitle = "Proceedings of the 13th International Conference on
Principles and Practice of Constraint Programming (CP 2007)",
Address = "Providence, Rhode Island, USA",
Editor = "C. Bessiere",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 4741,
Year = 2007,
Pages = "241--255",
ISBN = "978-3-540-74969-1",
Abstract = "We present the $w$ constraint combinator that models
while loops in Constraint Programming. Embedded in a
finite domain constraint solver, it allows programmers
to develop non-trivial arithmetical relations using
loops, exactly as in an imperative language style. The
deduction capabilities of this combinator come from
abstract interpretation over the polyhedra abstract
domain. This combinator has already demonstrated its
utility in constraint-based verification and we argue
that it also facilitates the rapid prototyping of
arithmetic constraints (e.g. power, gcd or sum)."
}
@Inproceedings{DooseM05,
Author = "D. Doose and Z. Mammeri",
Title = "Polyhedra-Based Approach for Incremental Validation
of Real-Time Systems",
Booktitle = "Proceedings of the International Conference on
Embedded and Ubiquitous Computing (EUC 2005)",
Address = "Nagasaki, Japan",
Editor = "L. T. Yang and M. Amamiya and Z. Liu and M. Guo and F. J. Rammig",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 3824,
Year = 2005,
Pages = "184--193",
ISBN = "3-540-30807-5",
Abstract = "Real-time embedded systems can be used in hightly
important or even vital tasks (avionic and medical
systems, etc.), thus having strict temporal constraints
that need to be validated. Existing solutions use
temporal logic, automata or scheduling
techniques. However, scheduling techniques are often
pessimistic and require an almost complete knowledge of
the system, and formal methods can be ill-fitted to
manipulate some of the concepts involved in real-time
systems. In this article, we propose a method that
gives to the designer the advantages of formal methods
and some simplicity in manipulating real-time systems
notions. This method is able to model and validate all
the classical features of real-time systems, without any
pessimism, while guaranteeing the terminaison of the
validation process. Moreover, its formalism enables to
study systems of which we have only a partial knowledge,
and thus to validate or invalidate a system still under
design. This latest point is very important, since it
greatly decreases the cost of design backtracks."
}
@Inproceedings{DoyenHR05,
Author = "L. Doyen and T. A. Henzinger and J.-F. Raskin",
Title = "Automatic Rectangular Refinement of Affine Hybrid Systems",
Booktitle = "Proceedings of the 3rd International Conference
on Formal Modeling and Analysis of Timed Systems (FORMATS 2005)",
Address = "Uppsala, Sweden",
Editor = "P. Pettersson and W. Yi",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 3829,
Pages = "144--161",
Year = 2005,
ISBN = "3-540-30946-2",
Abstract = "We show how to automatically construct and refine
rectangular abstractions of systems of linear
differential equations. From a hybrid automaton whose
dynamics are given by a system of linear differential
equations, our method computes automatically a sequence
of rectangular hybrid automata that are increasingly
precise overapproximations of the original hybrid
automaton. We prove an optimality criterion for
successive refinements. We also show that this method
can take into account a safety property to be verified,
refining only relevant parts of the state space. The
practicability of the method is illustrated on a
benchmark case study."
}
@Techreport{DoyenHR05TR,
Author = "L. Doyen and T. A. Henzinger and J.-F. Raskin",
Title = "Automatic Rectangular Refinement of Affine Hybrid Systems",
Number = "2005.47",
Institution = "Centre F\'ed\'er\'e en V\'erification,
Universit\'e Libre de Bruxelles, Belgium",
Year = 2005,
Abstract = "We show how to automatically construct and refine
rectangular abstractions of systems of linear
differential equations. From a hybrid automaton whose
dynamics are given by a system of linear differential
equations, our method computes automatically a sequence
of rectangular hybrid automata that are increasingly
precise overapproximations of the original hybrid
automaton. We prove an optimality criterion for
successive refinements. We also show that this method
can take into account a safety property to be verified,
refining only relevant parts of the state space. The
practicability of the method is illustrated on a
benchmark case study."
}
@PhdThesis{Doyen06th,
Author = "L. Doyen",
Title = "Algorithmic Analysis of Complex Semantics
for Timed and Hybrid Automata",
School = "Universit\'e Libre de Bruxelles",
Address = "Bruxelles, Belgium",
Month = jun,
Year = 2006,
Abstract = "In the field of formal verification of real-time
systems, major developments have been recorded in the
last fifteen years. It is about logics, automata,
process algebra, programming languages, etc. From the
beginning, a formalism has played an important role:
\emph{timed automata} and their natural extension,
\emph{hybrid automata}. Those models allow the
definition of real-time constraints using real-valued
\emph{clocks}, or more generally \emph{analog variables}
whose evolution is governed by differential
equations. They generalize finite automata in that their
semantics defines \emph{timed words} where each symbol
is associated with an occurrence timestamp.
The \emph{decidability} and \emph{algorithmic analysis}
of timed and hybrid automata have been intensively
studied in the literature. The central result for timed
automata is that they are positively decidable. This is
not the case for hybrid automata, but semi-algorithmic
methods are known when the dynamics is relatively
simple, namely a linear relation between the derivatives
of the variables. With the increasing complexity of
nowadays systems, those models are however limited in
their classical semantics, for modelling realistic
implementations or dynamical systems.
In this thesis, we study the algorithmics of
\emph{complex semantics} for timed and hybrid automata.
On the one hand, we propose implementable semantics for
timed automata and we study their computational
properties: by contrast with other works, we identify a
semantics that is implementable and that has decidable
properties. On the other hand, we give new algorithmic
approaches to the analysis of hybrid automata whose
dynamics is given by an affine function of its
variables."
}
@MastersThesis{Ellenbogen04th,
Author = "R. Ellenbogen",
Title = "Fully Automatic Verification of Absence of Errors
via Interprocedural Integer Analysis",
School = "School of Computer Science, Tel-Aviv University",
Address = "Tel-Aviv, Israel",
Month = dec,
Year = 2004,
Abstract = "We present a interprocedural C String Static Verifier
(iCSSV), a whole program analysis algorithm for
verifying the safety of string operations in C
programs. The algorithm automatically proves linear
relationships among pointer expressions. The algorithm
is conservative, i.e., it infers only valid
relationships although it may fail to detect some of
them. The algorithm is targeted to programs with
``shallow'' pointers and complex integer
relationships. Therefore, the algorithm combines
context-sensitive flow-insensitive pointer analysis of
pointer updates with contextsensitive and flow-sensitive
integer analysis of properties of allocation
sites. Context-sensitivity is achieved by specializing
pointer aliases to the context and functional integer
analysis. The algorithm is powerful enough to verify the
absence of string manipulation errors such as accesses
beyond buffer length and null terminating
character. Here the interprocedural analysis guarantees
that our algorithm is fully automatic, i.e., does not
require user annotations or any other intervention. A
prototype of the algorithm was implemented. Several
novel techniques are employed to make the
interprocedural analysis of realistic programs
feasible."
}
@Inproceedings{FagesR09,
Author = "F. Fages and A. Rizk",
Title = "From Model-Checking to Temporal Logic Constraint Solving",
Booktitle = "Proceedings of the 15th International Conference
on Principles and Practice of Constraint Programming (CP 2009)",
Address = "Lisbon, Portugal",
Editor = "I. P. Gent",
Series = "Lecture Notes in Computer Science",
Volume = 5732,
Year = 2009,
Pages = "319--334",
Publisher = "Springer-Verlag, Berlin",
ISBN = "978-3-642-04243-0",
Abstract = "In this paper, we show how model-checking can be
generalized to temporal logic constraint solving, by
considering temporal logic formulae with free variables
over some domain ${\mathcal D}$, and by computing a
validity domain for the variables rather than a truth
value for the formula. This allows us to define a
continuous degree of satisfaction for a temporal logic
formula in a given structure, opening up the field of
model-checking to optimization. We illustrate this
approach with reverse-engineering problems coming from
systems biology, and provide some performance figures on
parameter optimization problems with respect to temporal
logic specifications."
}
@Inproceedings{FenacciM11,
Author = "D. Fenacci and K. MacKenzie",
Title = "Static Resource Analysis for {Java} Bytecode Using Amortisation
and Separation Logic",
Booktitle = "Proceedings of the 6th Workshop on Bytecode Semantics,
Verification, Analysis and Transformation (Bytecode 2011)",
Address = "Saarbrucken, Germany",
Series = "Electronic Notes in Theoretical Computer Science",
Publisher = "Elsevier Science B.V.",
Volume = 279,
Number = 1,
Pages = "19--32",
Year = 2011,
ISSN = "1571-0661",
Abstract = "In this paper we describe a static analyser for Java
bytecode which uses a combination of amortised analysis
and Separation Logic due to Robert Atkey. With the help
of Java annotations we are able to give precise resource
utilisation constraints for Java methods which
manipulate various heap-based data structures."
}
@Inproceedings{FioravantiPPS12,
Author = "F. Fioravanti and A. Pettorossi and M. Proietti and V. Senni",
Title = "Using Real Relaxations during Program Specialization",
Booktitle = "Logic Program Synthesis and Transformation:
Proceedings of the 21st International Symposium",
Address = "Odense, Denmark",
Editor = "G. Vidal",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 7225,
Pages = "106--122",
Year = 2012,
ISBN = "978-3-642-32210-5 (Print) 978-3-642-32211-2 (Online)",
Abstract = "We propose a program specialization technique for
locally stratified CLP(Z) programs, that is, logic
programs with linear constraints over the set Z of the
integer numbers. For reasons of efficiency our technique
makes use of a relaxation from integers to reals. We
reformulate the familiar unfold/fold transformation
rules for CLP programs so that: (i) the applicability
conditions of the rules are based on the satisfiability
or entailment of constraints over the set R of the real
numbers, and (ii) every application of the rules
transforms a given program into a new program with the
same perfect model constructed over Z. Then, we
introduce a strategy which applies the transformation
rules for specializing CLP(Z) programs with respect to a
given query. Finally, we show that our specialization
strategy can be applied for verifying properties of
infinite state reactive systems specified by constraints
over Z."
}
@Article{FioravantiPPS12-FI,
Author = "F. Fioravanti and A. Pettorossi and M. Proietti and V. Senni",
Title = "Improving Reachability Analysis of Infinite State Systems by Specialization",
Journal = "Fundamenta Informaticae",
Publisher = "IOS Press",
Volume = 119,
Number = "3--4",
Pages = "281--300",
Year = 2012,
ISSN = "0169-2968 (Print) 1875-8681 (Online)",
Abstract = "We consider infinite state reactive systems specified by
using linear constraints over the integers, and we
address the problem of verifying safety properties of
these systems by applying reachability analysis
techniques. We propose a method based on program
specialization, which improves the effectiveness of the
backward and forward reachability analyses. For backward
reachability our method consists in: (i) specializing
the reactive system with respect to the initial states,
and then (ii) applying to the specialized system the
reachability analysis that works backwards from the
unsafe states. For reasons of efficiency, during
specialization we make use of a relaxation from integers
to reals. In particular, we test the satisfiability or
entailment of constraints over the real numbers, while
preserving the reachability properties of the reactive
systems when constraints are interpreted over the
integers. For forward reachability our method works as
for backward reachability, except that the role of the
initial states and the unsafe states are
interchanged. We have implemented our method using the
MAP transformation system and the ALV verification
system. Through various experiments performed on several
infinite state systems, we have shown that our
specialization-based verification technique considerably
increases the number of successful verifications without
a significant degradation of the time performance."
}
@MastersThesis{Flexeder05th,
Author = "A. Flexeder",
Title = "{Interprozedurale Analyse linearer Ungleichungen}",
Type = "Diploma thesis",
School = "Technische {Universit\"at} {M\"unchen}",
Address = "{M\"unchen}, Germany",
Month = jul,
Year = 2005,
Note = "In German",
Abstract = "{Diese Arbeit beschreibt eine intra- und auch
interprozedurale Datenflussanalyse, welche an jedem
Programmpunkt statisch die Beziehungen, die zwischen den
Programmvariablen gelten, bestimmen k\"onnen. Die
intraprozeduralen Analyse, beruhend auf einem Modell von
Cousot [P.~Cousot and N.~Halbwachs. Automatic discovery
of linear restraints among variables of a program.
Conference Record of the 5th Annunal ACM Symposium on
Principles of Programming Languages, pages 84--96, 1978]
interpretiert lineare Zuweisungen und Bedingungen und
betrachtet die nicht linearen Konstrukte mit Hilfe von
nicht linearen Zuweisungen. Mit dieser Abstraktion
versucht man lineare Gleichheits- und
Ungleichheitsbeziehungen zwischen den Programmvariablen
in Form von Polyedern rauszufinden. Da man nicht nur
eine Funktion, sondern ganze Programme als Zusammenspiel
mehrerer Funktionen, analysieren m\"ochte, ist eine
interprozedurale Analyse n\"otig [M.~Mueller-Olm and
H.~Seidl. Precise Interprocedural Analysis through
Linear Algebra. POPL, 2004]. Diese soll mit den Mitteln
der linearen Algebra die affinen Beziehungen, welche
zwischen den Programmvariablen an einem bestimmten
Programmpunkt gelten, erkennen. Die Behandlung von
Prozeduraufrufen steht dabei im Vordergrund.}"
}
@Inproceedings{FouiheMP13,
Author = "A. Fouilhe and D. Monniaux and M. P{\'e}rin",
Title = "Efficient Generation of Correctness Certificates
for the Abstract Domain of Polyhedra",
Booktitle = "Static Analysis:
Proceedings of the 20th International Symposium (SAS 2013)",
Address = "Seattle, USA",
Series = "Lecture Notes in Computer Science",
Editor = "F. Logozzo and M. F{\"a}hndrich",
Publisher = "Springer-Verlag, Berlin",
ISBN = "978-3-642-38855-2 (Print) 978-3-642-38856-9 (Online)",
Volume = 7935,
pages = "345--365",
Year = 2013,
Abstract = "Polyhedra form an established abstract domain for
inferring runtime properties of programs using abstract
interpretation. Computations on them need to be
certified for the whole static analysis results to be
trusted. In this work, we look at how far we can get
down the road of a posteriori verification to lower the
overhead of certification of the abstract domain of
polyhedra. We demonstrate methods for making the cost of
inclusion certificate generation negligible. From a
performance point of view, our single-representation,
constraints-based implementation compares with
state-of-the-art implementations."
}
@MastersThesis{FrankM02th,
Author = "S. Frank and P. R. Mai",
Title = "Strategies for Cooperating Constraint Solvers",
Type = "Diploma thesis",
School = "Technische {Universit\"at} Berlin",
Address = "Berlin, Germany",
Month = jul,
Year = 2002,
Abstract = "Cooperative constraint solving has been investigated by
several different research groups and individuals as it
provides a comfortable mechanism to attack multi-domain
constraint problems. The theoretical framework of
Hofstedt [P.~Hofstedt. Cooperation and Coordination of
Constraint Solvers. PhD thesis, Technische
{Universit\"at} Dresden, March 2001. Shaker Verlag,
Aachen] provided the basis for the prototypical
implementation described in [E.~Godehardt and
D.~Seifert. Kooperation und Koordination von Constraint
Solvern --- Implementierung eines Prototyps. Master's
thesis, Technische Universit{\"a}t Berlin, January
2001]. Taking aboard the lessons learned in the
prototype, we introduce a revised implementation of the
framework, to serve as a flexible basis for the
conception and evaluation of advanced strategies for
solver cooperation. Several additional enhancements and
optimisations over the preceding implementation or the
underlying theoretical framework are described, proving
the correctness of those changes where necessary. Using
the newly implemented framework, we propose and
benchmark a set of new cooperation strategies,
iteratively refining them to the point where we can
offer a set of generally useful (i.e. non-problem
specific) strategies. Finally we introduce a strategy
language, that allows the user to define
problem-specific strategies, either from scratch or
derived from other strategies, and demonstrate the
effectiveness of the language on a well-known example
problem."
}
@Inproceedings{Frehse04,
Author = "G. Frehse",
Title = "Compositional Verification of Hybrid Systems
with Discrete Interaction Using Simulation Relations",
Booktitle = "Proceedings of the IEEE Conference on Computer Aided
Control Systems Design (CACSD 2004)",
Address = "Taipei, Taiwan",
Year = 2004,
Abstract = "Simulation relations can be used to verify refinement
between a system and its specification, or between
models of different complexity. It is known that for the
verification of safety properties, simulation between
hybrid systems can be defined based on their labeled
transition system semantics. We show that for hybrid
systems without shared variables, which therefore only
interact at discrete events, this simulation preorder is
compositional, and present assume-guarantee rules that
help to counter the state explosion problem. Some
experimental results for simulation checking of linear
hybrid automata are provided using a prototype tool with
exact arithmetic and unlimited digits."
}
@Inproceedings{FrehseHK04,
Author = "G. Frehse and Z. Han and B. Krogh",
Title = "Assume-Guarantee Reasoning for Hybrid {I/O}-Automata
by Over-Approximation of Continuous Interaction",
Booktitle = "Proceedings of the
43rd IEEE Conference on Decision and Control (CDC 2004)",
Address = "Atlantis, Paradise Island, Bahamas",
Year = 2004,
Abstract = "This paper extends assume-guarantee reasoning (AGR) to
hybrid dynamic systems that interact through continuous
state variables. We use simulation relations for timed
transition systems to analyze compositions of hybrid I/O
automata. This makes it possible to perform
compositional reasoning that is conservative in the
sense of over approximating the composed behaviors. In
contrast to previous approaches that require global
receptivity conditions, circularity is broken in our
approach by a state-based nonblocking condition that can
be checked in the course of computing the AGR simulation
relations. The proposed procedures for AGR are
implemented in a computational tool for the case of
linear hybrid I/O automata, and the approach is
illustrated with a simple example."
}
@Inproceedings{Frehse05,
Author = "G. Frehse",
Title = "{PHAVer}: Algorithmic Verification of Hybrid Systems Past {HyTech}",
Booktitle = "Hybrid Systems: Computation and Control:
Proceedings of the 8th International Workshop (HSCC 2005)",
Address = "Z{\"u}rich, Switzerland",
Editor = "M. Morari and L. Thiele",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 3414,
Pages = "258--273",
Year = 2005,
Abstract = "In 1995, HyTech broke new ground as a potentially
powerful tool for verifying hybrid systems --- yet it has
remained severely limited in its applicability to more
complex systems. We address the main problems of HyTech
with PHAVer, a new tool for the exact verification of
safety properties of hybrid systems with piecewise
constant bounds on the derivatives. Affine dynamics are
handled by on-the-fly overapproximation and by
partitioning the state space based on user-definable
constraints and the dynamics of the system. PHAVer's
exact arithmetic is robust due to the use of the Parma
Polyhedra Library, which supports arbitrarily large
numbers. To manage the complexity of the polyhedral
computations, we propose methods to conservatively limit
the number of bits and constraints of polyhedra.
Experimental results for a navigation benchmark and a
tunnel diode circuit show the effectiveness of the
approach."
}
@PhdThesis{Frehse05th,
Author = "G. Frehse",
Title = "Compositional Verification of Hybrid Systems
using Simulation Relations",
School = "Radboud Universiteit Nijmegen",
Address = "Nijmegen, The Netherlands",
Month = oct,
Year = 2005,
}
@Article{Frehse08,
Author = "G. Frehse",
Title = "{PHAVer}: Algorithmic Verification of Hybrid Systems Past {HyTech}",
Journal = "Software Tools for Technology Transfer",
Publisher = "Springer-Verlag, Berlin",
Volume = 10,
Number = 3,
Year = 2008,
Pages = "263--279",
Abstract = "In 1995, HyTech broke new ground as a potentially
powerful tool for verifying hybrid systems --- yet its
appicability remains limited to relatively simple
systems. We address the main problems of HyTech with
PHAVer, a new tool for the exact verification of safety
properties of hybrid systems with piecewise constant
bounds on the derivatives. Affine dynamics are handled
by on-the-fly overapproximation, partitioning the state
space based on user-definable constraints and the
dynamics of the system. PHAVer features exact arithmetic
in a robust implementation that, based on the Parma
Polyhedra Library, supports arbitrarily large
numbers. To manage the complexity of the polyhedral
computations, we propose methods to conservatively limit
the number of bits and constraints of
polyhedra. Experimental results for a navigation
benchmark and a tunnel diode circuit show the
effectiveness of the approach."
}
@Inproceedings{FrehseKRM06,
Author = "G. Frehse and B. H. Krogh and R. A. Rutenbar and O. Maler",
Title = "Time Domain Verification of Oscillator Circuit Properties",
Booktitle = "Proceedings of the First Workshop on Formal Verification
of Analog Circuits (FAC 2005)",
Address = "Edinburgh, Scotland",
Pages = "9--22",
Series = "Electronic Notes in Theoretical Computer Science",
Publisher = "Elsevier Science B.V.",
Volume = 153,
Number = 3,
Year = 2006,
Abstract = "The application of formal methods to analog and mixed
signal circuits requires efficient methods for
constructing abstractions of circuit behaviors. This
paper concerns the verification of properties of
oscillator circuits. Generic monitor automata are
proposed to facilitate the application of hybrid system
reachability computations to characterize time domain
features of oscillatory behavior, such as bounds on the
signal amplitude and jitter. The approach is illustrated
for a nonlinear tunnel-diode circuit model using PHAVer,
a hybrid system analysis tool that provides sound
verification results based on linear hybrid automata
approximations and infinite precision computations."
}
@Inproceedings{FrehseKR06,
Author = "G. Frehse and B. H. Krogh and R. A. Rutenbar",
Title = "Verifying Analog Oscillator Circuits Using Forward/Backward
Refinement",
Booktitle = "Proceedings of the 9th Conference on Design, Automation
and Test in Europe (DATE 06)",
Address = "Munich, Germany",
Publisher = "ACM SIGDA",
Year = 2006,
Note = "{CD-ROM} publication",
Abstract = "Properties of analog circuits can be verified formally
by partitioning the continuous state space and applying
hybrid system verification techniques to the resulting
abstraction. To verify properties of oscillator
circuits, cyclic invariants need to be computed. Methods
based on forward reachability have proven to be
inefficient and in some cases inadequate in constructing
these invariant sets. In this paper we propose a novel
approach combining forward- and backward-reachability
while iteratively refining partitions at each step. The
technique can yield dramatic memory and runtime
reductions. We illustrate the effectiveness by
verifying, for the first time, the limit cycle
oscillation behavior of a third-order model of a
differential VCO circuit."
}
@Inproceedings{FribourgK11,
author = "L. Fribourg and U. K{\"u}hne",
title = "Parametric Verification and Test Coverage for Hybrid Automata
Using the Inverse Method",
Booktitle = "In Proceedings of the 5th International Workshop
on Reachability Problems (RP 2011)",
Address = "Genova, Italy",
Series = "Lecture Notes in Computer Science",
Editor = "G. Delzanno and I. Potapov",
Publisher = "Springer-Verlag, Berlin",
ISBN = "978-3-642-24287-8",
Pages = "191--204",
Volume = 6945,
Year = 2011,
Abstract = "Hybrid systems combine continuous and discrete
behavior. Hybrid Automata are a powerful formalism for
the modeling and verification of such systems. A common
problem in hybrid system verification is the good
parameters problem, which consists in identifying a set
of parameter valuations which guarantee a certain
behavior of a system. Recently, a method has been
presented for attacking this problem for Timed
Automata. In this paper, we show the extension of this
methodology for hybrid automata with linear and affine
dynamics. The method is demonstrated with a hybrid
system benchmark from the literature."
}
@Inproceedings{Fu14,
Author = "Z. Fu",
Title = "Modularly Combining Numeric Abstract Domains with Points-to Analysis, and a Scalable Static Numeric Analyzer for Java",
Booktitle = "Verification, Model Checking, and Abstract Interpretation:
Proceedings of the 15th International Conference (VMCAI 2014)",
Address = "San Diego, US",
Editor = "K. McMillan and X. Rival",
Publisher = "Springer-Verlag, Berlin",
Year = 2014,
Abstract = "This paper contributes to a new abstract domain that
combines static numeric analysis and points-to
analysis. One particularity of this abstract domain lies
in its high degree of modularity, in the sense that the
domain is constructed by reusing its combined components
as black-boxes. This modularity dramatically eases the
proof of its soundness and renders its algorithm
intuitive. We have prototyped the abstract domain for
analyzing real-world Java programs. Our experimental
results show a tangible precision enhancement compared
to what is possible by traditional static numeric
analysis, and this at a cost that is comparable to the
cost of running the numeric and pointer analyses
separately."
}
@Article{GallardoP13,
Author = "M.-d.-M. Gallardo and L. Panizo",
Title = "Extending Model Checkers for Hybrid System Verification:
The Case Study of {SPIN}",
Journal = "Software Testing, Verification and Reliability",
Publisher = "John Wiley & Sons, Ltd.",
DOI = "10.1002/stvr.1505",
ISSN ="1099-1689 (online)",
Year = 2013,
Note = "Early View (Online Version of Record published before inclusion in an issue)",
Abstract = "A hybrid system is a system that evolves following a
continuous dynamic, which may instantaneously change
when certain internal or external events occur. Because
of this combination of discrete and continuous dynamics,
the behaviour of a hybrid system is, in general,
difficult to model and analyse. Model checking
techniques have been proven to be an excellent approach
to analyse critical properties of complex systems. This
paper presents a new methodology to extend explicit
model checkers for hybrid systems analysis. The explicit
model checker is integrated, in a non-intrusive way,
with some external structures and existing abstraction
libraries, which store and manipulate the abstraction of
the continuous behaviour irrespective of the underlying
model checker. The methodology is applied to SPIN using
Parma Polyhedra Library. In addition, the authors are
currently working on the extension of other model
checkers."
}
@Inproceedings{MihailaSS13a,
Author = "P.-L. Garoche and T. Kahsai and C. Tinelli",
Title = "Incremental Invariant Generation Using Logic-Based Automatic Abstract Transformers",
Booktitle = "NASA Formal Methods:
Proceedings of the 5th International Symposium (NFM 2013)",
Editor = "G. Brat and N. Rungta and A. Venet",
Address = "Moffett Field, CA, USA",
Pages = "139--154",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 7871,
Year = 2013,
Abstract = "Formal analysis tools for system models often require or
benefit from the availability of auxiliary system
invariants. Abstract interpretation is currently one of
the best approaches for discovering useful invariants,
in particular numerical ones. However, its application
is limited by two orthogonal issues: (i) developing an
abstract interpretation is often non-trivial; each
transfer function of the system has to be represented at
the abstract level, depending on the abstract domain
used; (ii) with precise but costly abstract domains, the
information computed by the abstract interpreter can be
used only once a post fix point has been reached; this
may take a long time for large systems or when widening
is delayed to improve precision. We propose a new,
completely automatic, method to build abstract
interpreters which, in addition, can provide sound
invariants of the system under analysis before reaching
the end of the post fix point computation. In effect,
such interpreters act as on-the-fly invariant generators
and can be used by other tools such as logic-based model
checkers. We present some experimental results that
provide initial evidence of the practical usefulness of
our method."
}
@PhdThesis{Gobert07th,
Author = "F. Gobert",
Title = "Towards putting abstract interpretation of {Prolog} into practice:
design, implementation, and evaluation of a tool to verify
and optimise Prolog programs",
School = "Universit\'e catholique de Louvain",
Address = "Louvain-la-Neuve, Belgium",
Month = dec,
Year = 2007,
Abstract = "Logic programming is an attractive paradigm that allows
the programmer to concentrate on the meaning (the logic)
of the problem to be solved - the \emph{declarative layer}.
An execution model is then used as the problem solver - the
\emph{operational layer}. In practice, for efficiency reasons,
the semantics of the two layers do not always match. For
instance, in Prolog, the computation of solutions is based
on an incomplete depth-first search rule, unifications and
negations may be unsound, some builtin language primitives
are not multidirectional, and there exist extralogical
features like the cut or dynamic predicates. A large number
of work has been realised to reconcile the declarative and
operational features of Prolog. Methodologies have been
proposed to construct operationally correct and efficient
Prolog code. Researchers have designed methods to automate
the verification of specific operational properties on which
optimisation of logic programs can be based. A few tools have
been implemented but there is a lack of a unified framework.
The goal and topic of this thesis is the design, implementation,
and evaluation of a static analyser of Prolog programs to
integrate `state-of-the-art' techniques into a unified abstract
interpretation framework. Abstract interpretation is an
adequate methodology to design, justify, and combine complex
analyses. The analyser that we present in this thesis is based
on a non-implemented original proposal. The original framework
defines the notion of \emph{abstract sequence}, which allows
one to verify many desirable operational properties of a logic
procedure. The properties include verifying type, mode, and
sharing of terms, proving termination, sure success or failure,
and determinacy of logic procedures, as well as linear
relations between the size of input/output terms and the
number of solutions to a call. An abstract sequence maintains
information about the input and output terms, as well as the
non-failure conditions on input terms, and the number of
solutions for such inputs. The domains of abstract sequences
cooperate together and improve each other. The abstract
execution is performed during a single global analysis,
and abstract sequences are derived at each program point
(the information of the various domains are computed
simultaneously). The intended operational properties of a
procedure are written in formal specifications.
The original framework is an interesting starting point for
combining several analyses inside a unified framework.
However, it is limited and inaccurate in many ways: it is
not implemented, and therefore, it has not been validated
by experiments, it accepts only a subset of Prolog (without
negation, cut, conditional and disjunctive constructs), and
some of the proposed domains are not precise enough.
The basic framework is only oriented towards the verification
of Prolog programs, but it cannot always prove the desirable
properties. In this thesis, we implement and evaluate the
basic framework, and, more importantly, we overcome its
limitations to make it accurate and usable in practice:
the improved framework accepts any Prolog program with modules,
new abstract domains and operations are added, and the
language of specifications is more expressive. We also
design and implement an optimiser that generates specialised
code. Optimisation is essential in Prolog, but it is not easy
to perform by hand and it is error prone. The optimiser uses
the information to safely apply source-to-source
transformations. Code transformations include clause and
literal reordering, introduction of cuts, and removal
of redundant literals. The optimiser follows a precise
strategy to choose the most rewarding transformations in best
order.
This thesis shows the feasibility of a unified framework
that integrates many complex analyses in a single global
analysis. Practically and theoretically, a single global
analysis is more attractive than a combination of a lot of
separate analyses and frameworks. Many extensions have been
performed to obtain an accurate and usable tool devoted to
verification and optimisation of Prolog programs."
}
@Inproceedings{GobertLC07,
Author = "F. Gobert and B. {Le Charlier}",
Title = "A System to Check Operational Properties of Logic Programs",
Pages = "245--259",
Booktitle = "Approches Formelles dans l'Assistance au D\'eveloppement
de Logiciels: Actes de la 8e conf\'erence",
Publisher = "Universit\'e de Namur, Belgium",
Editor = "M.-L. Potet and P.-Y. Schobbens and H. Toussaint and G. Saval",
Year = 2007,
ISBN = "978-2-87037-559-4",
Abstract = "An implemented static analyser of logic programs is presented.
The system is based on a unied abstract interpretation
framework, which allows the integration of several analyses
devoted to verication and optimisation. The analyser is able
to verify many desirable properties of logic programs executed
with the search-rule and other specic features of Prolog.
Such operational properties include verifying type, mode,
sharing, and linearity of terms, proving termination,
occur-check freeness, sure success or failure, and determinacy
of logic procedures, as well as linear relations between the
size of input/output terms and the number of solutions to a
call. It is emphasized how each analysis may contribute to
each other.",
}
@Inproceedings{GonnordH06,
Author = "L. Gonnord and N. Halbwachs",
Title = "Combining Widening and Acceleration in Linear Relation Analysis",
Booktitle = "Static Analysis:
Proceedings of the 13th International Symposium",
Address = "Seoul, Korea",
Editor = "K. Yi",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 4134,
Pages = "144--160",
Year = 2006,
ISBN = "3-540-37756-5",
Abstract = "Linear Relation Analysis [CH78,Hal79] is one of the
first, but still one of the most powerful, abstract
interpretations working in an infinite lattice. As such,
it makes use of a widening operator to enforce the
convergence of fixpoint computations. While the
approximation due to widening can be arbitrarily refined
by delaying the application of widening, the analysis
quickly becomes too expensive with the increase of
delay. Previous attempts at improving the precision of
widening are not completely satisfactory, since none of
them is guaranteed to improve the precision of the
result, and they can nevertheless increase the cost of
the analysis. In this paper, we investigate an
improvement of Linear Relation Analysis consisting in
computing, when possible, the exact (abstract) effect of
a loop. This technique is fully compatible with the use
of widening, and whenever it applies, it improves both
the precision and the performance of the analysis.",
}
@PhdThesis{Gopan07th,
Author = "D. Gopan",
Title = "Numeric Program Analysis Techniques with Applications
to Array Analysis and Library Summarization",
School = "University of Wisconsin",
Address = "Madison, Wisconsin, USA",
Month = aug,
Year = 2007,
Abstract = "Numeric program analysis is of great importance for the
areas of software engineering, software
verification, and security: to identify many program
errors, such as out-of-bounds array accesses and
integer overflows, which constitute the lion's share
of security vulnerabilities reported by CERT, an
analyzer needs to establish numeric properties of
program variables. Many important program analyses,
such as low-level code analysis, memory-cleanness
analysis, and shape analysis, rely in some ways on
numeric-program-analysis techniques. However,
existing numeric abstractions are complex (numeric
abstract domains are typically non-distributive, and
form infinite-height lattices); thus, obtaining
precise numeric-analysis results is by no means a
trivial undertaking.
In this thesis, we develop a suite of techniques with
the common goal of improving the precision and applicability
of numeric program analysis. The techniques address
various aspects of numeric analysis, such as
handling dynamically-allocated memory, dealing with
programs that manipulate arrays, improving the
precision of extrapolation (widening), and
performing interprocedural analysis. The techniques
use existing numeric abstractions as building
blocks. The communication with existing abstractions
is done strictly through a generic abstract-domain
interface. The abstractions constructed by our
techniques also expose that same interface, and
thus, are compatible with existing analysis
engines. As a result, our techniques are independent
from specific abstractions and specific analysis
engines, can be easily incorporated into existing
program-analysis tools, and should be readily
compatible with new abstractions to be introduced in
the future.
A practical application of numeric analysis that we consider
in this thesis is the automatic generation of summaries for
library functions from their low-level
implementation (that is, from a library's
binary). The source code for library functions is
typically not available. This poses a stumbling
block for many source-level program
analyses. Automatic generation of summary functions
will both speed up and improve the accuracy of
library-modeling, a process that is currently
carried out by hand. This thesis addresses the
automatic generation of summaries for memory-safety
analysis."
}
@Inproceedings{GopanR06,
Author = "D. Gopan and T. W. Reps",
Title = "Lookahead Widening",
Booktitle = "Computer Aided Verification:
Proceedings of the 18th International Conference (CAV 2006)",
Address = "Seattle, Washington, USA",
Editor = "T. Ball and R. B. Jones",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 4144,
Pages = "452--466",
Year = 2006,
Abstract = "We present \emph{lookahead widening}, a novel technique
for using existing widening and narrowing operators to
improve the precision of static analysis. This technique
is both self-contained and fully-automatic in the sense
that it does not rely on separate analyzes or human
involvement. We show how to integrate lookahead widening
into existing analyzers with minimal
effort. Experimental results indicate that the technique
is able to achieve sizable precision improvements at
reasonable costs.",
}
@Inproceedings{GopanR07a,
Author = "D. Gopan and T. W. Reps",
Title = "Low-Level Library Analysis and Summarization",
Booktitle = "Computer Aided Verification:
Proceedings of the 19th International Conference (CAV 2007)",
Address = "Berlin, Germany",
Editor = "W. Damm and H. Holger",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 4590,
Pages = "68--81",
Year = 2007,
ISBN = "3-540-73367-6",
Abstract = "Programs typically make extensive use of libraries,
including dynamically linked libraries, which are often
not available in source-code form, and hence not
analyzable by tools that work at source level (i.e.,
that analyze intermediate representations created from
source code). A common approach is to write
\emph{library models} by hand. A library model is a
collection of function stubs and variable declarations
that capture some aspect of the library code's
behavior. Because these are hand-crafted, they are
likely to contain errors, which may cause an analysis to
return incorrect results.
This paper presents a method to construct summary
information for a library function automatically by
analyzing its low-level implementation (i.e., the
library's binary).",
}
@Inproceedings{GopanR07b,
Author = "D. Gopan and T. W. Reps",
Title = "Guided Static Analysis",
Booktitle = "Static Analysis:
Proceedings of the 14th International Symposium",
Address = "Kongens Lyngby, Denmark",
Editor = "G. Fil\'e and H. R. Nielson",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 4634,
ISBN = "978-3-540-74060-5",
Pages = "349--365",
Year = 2007,
Abstract = "In static analysis, the semantics of the program is
expressed as a set of equations. The equations are
solved iteratively over some abstract domain. If the
abstract domain is distributive and satisfies the
ascending-chain condition, an iterative technique yields
the most precise solution for the equations. However, if
the above properties are not satisfied, the solution
obtained is typically imprecise. Moreover, due to
the properties of widening operators, the precision loss
is sensitive to the order in which the state-space is
explored.
In this paper, we introduce \emph{guided static analysis},
a framework for controlling the exploration of the
state-space of a program. The framework guides the
state-space exploration by applying standard
static-analysis techniques to a sequence of modified
versions of the analyzed program. As such, the framework
does not require any modifications to existing analysis
techniques, and thus can be easily integrated into
existing static-analysis tools.
We present two instantiations of the framework, which
improve the precision of widening in (i) loops with
multiple phases and (ii) loops in which the transformation
performed on each iteration is chosen non-deterministically.",
}
@Inproceedings{GopanRS05,
Author = "D. Gopan and T. W. Reps and M. Sagiv",
Title = "A Framework for Numeric Analysis of Array Operations",
Booktitle = "Proceedings of the 32nd ACM SIGPLAN-SIGACT Symposium
on Principles of Programming Languages",
Address = "Long Beach, California, USA",
Pages = "338--350",
Year = 2005,
Abstract = "Automatic discovery of relationships among values of
array elements is a challenging problem due to the
unbounded nature of arrays. We present a framework for
analyzing array operations that is capable of capturing
numeric properties of array elements. In particular, the
analysis is able to establish that all array elements
are initialized by an array-initialization loop, as well
as to discover numeric constraints on the values of
initialized elements. The analysis is based on the
combination of canonical abstraction and summarizing
numeric domains. We describe a prototype implementation
of the analysis and discuss our experience with applying
the prototype to several examples, including the
verification of correctness of an insertion-sort
procedure."
}
@Inproceedings{BandaG10a,
Author = "G. Banda and J. P. Gallagher",
Title = "Constraint-Based Abstraction of a Model Checker
for Infinite State Systems",
Booktitle = "Proceedings of the 23rd Workshop on (Constraint)
Logic Programming (WLP 2009)",
Editor = "U. Geske and A. Wolf",
Address = "Potsdam, Germany",
Publisher = "Potsdam Universit{\"a}tsverlag",
Year = 2010,
Pages = "109--124",
Abstract = "Abstract interpretation-based model checking provides an
approach to verifying properties of infinite-state
systems. In practice, most previous work on abstract
model checking is either restricted to verifying
universal properties, or develops special techniques for
temporal logics such as modal transition systems or
other dual transition systems. By contrast we apply
completely standard techniques for constructing abstract
interpretations to the abstraction of a CTL semantic
function, without restricting the kind of properties
that can be verified. Furthermore we show that this
leads directly to implementation of abstract model
checking algorithms for abstract domains based on
constraints, making use of an SMT solver."
}
@Inproceedings{BandaG10b,
Author = "G. Banda and J. P. Gallagher",
Title = "Constraint-Based Abstract Semantics for Temporal Logic:
A Direct Approach to Design and Implementation",
Booktitle = "Proceedings of the 17th International Conference
on Logic for Programming,
Artificial Intelligence, and Reasoning (LPAR 2010)",
Address = "Yogyakarta, Indonesia",
Series = "Lecture Notes in Computer Science",
Editor = "E. Clarke and A. Voronkov",
Publisher = "Springer-Verlag, Berlin",
ISBN = "978-3-642-17510-7",
Year = 2010,
Pages = "27--45",
Volume = 6355,
Abstract = "Abstract interpretation provides a practical approach
to verifying properties of infinite-state systems. We
apply the framework of abstract interpretation to
derive an abstract semantic function for the modal ?
-calculus, which is the basis for abstract model
checking. The abstract semantic function is constructed
directly from the standard concrete semantics together
with a Galois connection between the concrete
state-space and an abstract domain. There is no need
for mixed or modal transition systems to abstract
arbitrary temporal properties, as in previous work in
the area of abstract model checking. Using the modal ?
-calculus to implement CTL, the abstract semantics
gives an over-approximation of the set of states in
which an arbitrary CTL formula holds. Then we show that
this leads directly to an effective implementation of
an abstract model checking algorithm for CTL using
abstract domains based on linear constraints. The
implementation of the abstract semantic function makes
use of an SMT solver. We describe an implemented system
for proving properties of linear hybrid automata and
give some experimental results."
}
@Inproceedings{Grosser09,
Author = "T. Grosser",
Title = "Optimization opportunities based on the polyhedral model in
{GRAPHITE}. How much impact has {GRAPHITE} already?",
Booktitle = "Proceedings of the {GCC} Developers' Summit",
Address = "Montreal, Quebec, Canada",
Year = 2009,
Month = jun,
Pages = "33--46",
URL = "http://www.gccsummit.org/2009/gcc09-proceedings.pdf",
Abstract = "The polytope model is used since many years to describe
standard loop optimizations like blocking, interchange
or fusion, but also advanced memory access optimizations
and automatic parallelization. Its exact mathematical
description of memory accesses and loop iterations
allows to concentrate on the optimization problem and to
take advantage of professional problem solving tools
developed for operational research. Up to today the
polytope model was limited to research compilers or
source to source transformations. Graphite generates a
polytope description of all programs compiled by the
gcc. Therefore polytope optimization techniques are not
limited anymore to hand selected code pieces, but can
actually be applied in large scale on real world
programs. By showing the impact of GRAPHITE on important
benchmarks --- ``How much runtime is actually spent in
code, that can be optimized by polytope optimization
techniques?'' --- we invite people to base their current
polytope research on GRAPHITE to make these
optimizations available to the large set of gcc compiled
applications."
}
@Inproceedings{GulavaniR06,
Author = "B. S. Gulavani and S. K. Rajamani",
Title = "Counterexample Driven Refinement for Abstract Interpretation",
Booktitle = "Proceedings of the 12th International Conference on
Tools and Algorithms for the Construction and Analysis
of Systems (TACAS 2006)",
Address = "Vienna, Austria",
Editor = "H. Hermanns and J. Palsberg",
Pages = "474--488",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 3920,
Year = 2006,
ISBN = "3-540-33056-9",
Abstract = "Abstract interpretation techniques prove properties of
programs by computing abstract fixpoints. All such
analyses suffer from the possibility of false errors. We
present a new counterexample driven refinement technique
to reduce false errors in abstract interpretations. Our
technique keeps track of the precision losses during
forward fixpoint computation, and does a precise
backward propagation from the error to either confirm
the error as a true error, or identify a refinement so
as to avoid the false error. Our technique is quite
simple, and is independent of the specific abstract
domain used. An implementation of our technique for
affine transition systems is able to prove invariants
generated by the StInG tool [19] without doing any
specialized analysis for linear relations. Thus, we hope
that the technique can work for other abstract domains
as well.We sketch how our technique can be used to
perform shape analysis by simply defining an appropriate
widening operator over shape graphs."
}
@Inproceedings{GulwaniL-AS09,
Author = "S. Gulwani and T. Lev-Ami and S. Sagiv",
Title = "A Combination Framework for Tracking Partition Sizes",
Booktitle = "Proceedings of the 36th ACM SIGPLAN-SIGACT Symposium on
Principles of Programming Languages (POPL 2009)",
Address = "Savannah, Georgia, USA",
Editor = "Z. Shao and B. C. Pierce",
Publisher = "ACM Press",
Pages = "239--251",
Year = 2009,
ISBN = "978-1-60558-379-2",
Abstract = "We describe an abstract interpretation based framework
for proving relationships between sizes of memory
partitions. Instances of this framework can prove
traditional properties such as memory safety and program
termination but can also establish upper bounds on usage
of dynamically allocated memory. Our framework also
stands out in its ability to prove properties of
programs manipulating both heap and arrays which is
considered a difficult task. Technically, we define an
abstract domain that is parameterized by an abstract
domain for tracking memory partitions (sets of memory
locations) and by a numerical abstract domain for
tracking relationships between cardinalities of the
partitions. We describe algorithms to construct the
transfer functions for the abstract domain in terms of
the corresponding transfer functions of the
parameterized abstract domains. A prototype of the
framework was implemented and used to prove interesting
properties of realistic programs, including programs
that could not have been automatically analyzed before."
}
@Article{HalbwachsMG06,
Author = "N. Halbwachs and D. Merchat and L. Gonnord",
Title = "Some Ways To Reduce the Space Dimension in Polyhedra Computations",
Journal = "Formal Methods in System Design",
Publisher = "Springer Netherlands",
Volume = 29,
Number = 1,
Pages = "79--95",
Year = 2006,
Abstract = "Convex polyhedra are often used to approximate sets of
states of programs involving numerical variables. The
manipulation of convex polyhedra relies on the so-called
\emph{double description}, consisting of viewing a
polyhedron both as the set of solutions of a system of
linear inequalities, and as the convex hull of a
\emph{system of generators}, i.e., a set of vertices and
rays. The cost of these manipulations is highly
dependent on the number of numerical variables, since
the size of each representation can be exponential in
the dimension of the space. In this paper, we
investigate some ways for reducing the dimension: On one
hand, when a polyhedron satisfies \emph{affine
equations}, these equations can obviously be used to
eliminate some variables. On the other hand, when groups
of variables are unrelated with each other, this means
that the polyhedron is in fact a \emph{Cartesian
product} of polyhedra of lower dimensions. Detecting
such Cartesian factoring is not very difficult, but we
adapt also the operations to work on Cartesian
products. Finally, we extend the applicability of
Cartesian factoring by applying suitable \emph{variable
change}, in order to maximize the factoring."
}
@Inproceedings{HalbwachsMP-V03,
Author = "N. Halbwachs and D. Merchat and C. Parent-Vigouroux",
Title = "Cartesian Factoring of Polyhedra in Linear Relation Analysis",
Booktitle = "Static Analysis:
Proceedings of the 10th International Symposium",
Address = "San Diego, California, USA",
Editor = "R. Cousot",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 2694,
Year = 2003,
Pages = "355--365",
Abstract = "Linear Relation Analysis [CH78] suffers from the cost of
operations on convex polyhedra, which can be exponential
with the number of involved variables. In order to
reduce this cost, we propose to detect when a polyhedron
is a Cartesian product of polyhedra of lower dimensions,
i.e., when groups of variables are unrelated with each
other. Classical operations are adapted to work on such
factored polyhedra. Our implementation shows encouraging
experimental results."
}
@Inproceedings{HenriksenG06,
Author = "K. S. Henriksen and J. P. Gallagher",
Title = "Abstract Interpretation of {PIC} Programs
through Logic Programming",
Booktitle = "Proceedings of the 6th IEEE International Workshop
on Source Code Analysis and Manipulation",
Address = "Sheraton Society Hill, Philadelphia, PA, USA",
Publisher = "IEEE Computer Society Press",
Pages = "184--196",
Year = 2006,
Abstract = "A logic based general approach to abstract
interpretation of low-level machine programs is
reported. It is based on modelling the behavior of the
machine as a logic program. General purpose program
analysis and transformation of logic programs, such as
partial evaluation and convex hull analysis, are applied
to the logic based model of the machine.
A small PIC microcontroller is used as a case study. An
emulator for this microcontroller is written in Prolog,
and standard programming transformations and analysis
techniques are used to specialise this emulator with
respect to a given PIC program. The specialised emulator
can now be further analysed to gain insight into the
given program for the PIC microcontroller.
The method describes a general framework for applying
abstractions, illustrated here by linear constraints and
convex hull analysis, to logic programs. Using these
techniques on the specialised PIC emulator, it is
possible to obtain constraints on and linear relations
between data registers, enabling detection of for
instance overflows, branch conditions and so on."
}
@PhdThesis{Henriksen07th,
Author = "K. S. Henriksen",
Title = "A Logic Programming Based Approach to Applying
Abstract Interpretation to Embedded Software",
School = "Computer Science, Roskilde University",
Month = oct,
Address = "Roskilde, Denmark",
Year = 2007,
Note = "Published as Computer Science Research Report \#117",
Abstract = "Abstract interpretation is a general framework for
static program analysis. In recent years this framework
has been used outside academia for verification of
embedded and real-time systems. Airbus and the European
Space Agency are examples of organisations that have
successfully adapted this analysis framework
for verification of critical components.
Logic programming is a programming paradigm with a sound
mathematical foundation. One of its characteristics is
the separation of logic (the meaning of a program) and
control (how it is executed); hence logic programming,
and in particular its extension with constraints, is a
language comparatively well suited for program analysis.
In this thesis logic programming is used to analyse
software developed for embedded systems. The particular
embedded system is modeled as an emulator written as a
constraint logic program. The emulator is specialised
with respect to some object program in order to obtain
a constraint logic program isomorphic to this object
program. Applying abstract interpretation based
analysers to the specialised emulator will provide
analysis results that can directly be related back
to the object program due to the isomorphism maintained
between the object program and the specialised emulator.
Two abstract interpretation based analysers for logic
programs have been developed. The first is a convex
polyhedron analyser for constraint logic programs
implementing a set of widening techniques for improved
precision of the analysis. The second analyser is a type
analysis tool for logic programs that automatically
derives a pre-interpretation from a regular type definition.
Additionallly, a framework for using a restricted form of
logic programming, namely Datalog, to express and check
program properties is described. At the end of the thesis
it is shown how instrumenting the semantics of the emulator
can be used to obtain, for instance, a fully automatic
Worst Case Execution Time analysis by applying the convex
polyhedron analyser to the instrumented and specialised
emulator. The tools developed in this thesis have all
been made available online for demonstration."
}
@Inproceedings{HenryMM12,
Author = "J. Henry and D. Monniaux and M. Moy",
Title = "Succinct Representations for Abstract Interpretation",
Booktitle = "Static Analysis:
Proceedings of the 19th International Symposium (SAS 2012)",
Address = "Deauville, France",
Editor = "A. Min{'e} and D. Schmidt",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 7460,
Year = 2012,
Pages = "283--299",
Abstract = "Abstract interpretation techniques can be made more
precise by distinguishing paths inside loops, at the
expense of possibly exponential complexity. SMT-solving
techniques and sparse representations of paths and sets
of paths avoid this pitfall.
We improve previously proposed techniques for guided
static analysis and the generation of disjunctive
invariants by combining them with techniques for
succinct representations of paths and symbolic
representations for transitions based on static single
assignment.
Because of the non-monotonicity of the results of
abstract interpretation with widening operators, it is
difficult to conclude that some abstraction is more
precise than another based on theoretical local
precision results. We thus conducted extensive
comparisons between our new techniques and previous
ones, on a variety of open-source packages."
}
@Inproceedings{HoweK12,
Author = "J. M. Howe and A. King",
Title = "Polyhedral Analysis Using Parametric Objectives",
Booktitle = "Static Analysis:
Proceedings of the 19th International Symposium (SAS 2012)",
Address = "Deauville, France",
Editor = "A. Min{'e} and D. Schmidt",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 7460,
Year = 2012,
Pages = "41--57",
Abstract = "The abstract domain of polyhedra lies at the heart of
many program analysis techniques. However, its
operations can be expensive, precluding their
application to polyhedra that involve many
variables. This paper describes a new approach to
computing polyhedral domain operations. The core of this
approach is an algorithm to calculate variable
elimination (projection) based on parametric linear
programming. The algorithm enumerates only non-redundant
inequalities of the projection space, hence permits
anytime approximation of the output."
}
@Inproceedings{HymansU04,
Author = "C. Hymans and E. Upton",
Title = "Static Analysis of Gated Data Dependence Graphs",
Booktitle = "Static Analysis:
Proceedings of the 11th International Symposium",
Address = "Verona, Italy",
Editor = "R. Giacobazzi",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 3148,
Year = 2004,
Pages = "197--211",
Abstract = "Several authors have advocated the use of the gated data
dependence graph as a compiler intermediate
representation. If this representation is to gain
acceptance, it is important to show that we may
construct static analyses which operate directly on
it. In this paper we present the first example of such
an analysis, developed using the methodology of abstract
interpretation. The analysis is shown to be sound with
respect to a concrete semantics for the representation.
Experimental results are presented which indicate that
the analysis performs well in comparison to conventional
techniques."
}
@Article{JhalaM09,
Author = "R. Jhala and R. Majumdar",
Title = "Software Model Checking",
Journal = "ACM Computing Surveys",
Volume = 41,
Number = 4,
Year = 2009,
Pages = "1--54",
Publisher = "ACM Press",
Address = "New York, NY, USA",
Abstract = "We survey recent progress in software model checking."
}
@Inproceedings{Jeannet10,
Author = "B. Jeannet",
Title = "Some Experience on the Software Engineering of
Abstract Interpretation Tools",
Booktitle = "Proceedings of Tools for Automatic Program AnalysiS
(TAPAS 2010)",
Address = "Perpignan, France",
Series = "Electronic Notes in Theoretical Computer Science",
Publisher = "Elsevier Science B.V.",
Volume = 267,
Number = 2,
Pages = "29--42",
Year = 2010,
ISSN = "1571-0661",
Abstract = "The ``right'' way of writing and structuring compilers is
well-known. The situation is a bit less clear for static
analysis tools. It seems to us that a static analysis
tool is ideally decomposed into three building blocks:
(1) a front-end, which parses programs, generates
semantic equations, and supervises the analysis process;
(2) a fixpoint equation solver, which takes equations
and solves them; (3) and an abstract domain, on which
equations are interpreted. The expected advantages of
such a modular structure is the ability of sharing
development efforts between analyzers for different
languages, using common solvers and abstract
domains. However putting in practice such ideal concepts
is not so easy, and some static analyzers merge for
instance the blocks (1) and (2).
We show how we instantiated these principles with three
different static analyzers (addressing resp. imperative
sequential programs, imperative concurrent programs, and
synchronous dataflow programs), a generic fixpoint
solver (Fixpoint), and two different abstract
domains. We discussed our experience on the advantages
and the limits of this approach compared to related
work."
}
@Inproceedings{JeannetM09,
Author = "B. Jeannet and A. Min{\'e}",
Title = "Apron: A Library of Numerical Abstract Domains for Static
Analysis",
Booktitle = "Computer Aided Verification:
Proceedings of the 21st International Conference (CAV 2009)",
Address = "Grenoble, France",
Editor = "A. Bouajjani and O. Maler",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 5643,
Pages = "661--667",
Year = 2009,
ISBN = "978-3-642-02657-7",
Abstract = "This article describes \textsc{Apron}, a freely
available library dedicated to the static analysis of
the numerical variables of programs by abstract
interpretation. Its goal is threefold: provide analysis
implementers with ready-to-use numerical abstractions
under a unified API, encourage the research in numerical
abstract domains by providing a platform for integration
and comparison, and provide teaching and demonstration
tools to disseminate knowledge on abstract
interpretation."
}
@Incollection {KhalilGP09,
Author = "G. Khalil and E. Goubault and S. Putot",
Title = "The Zonotope Abstract Domain {Taylor1+}",
Booktitle = "Computer Aided Verification:
Proceedings of the 21st International Conference (CAV 2009)",
Address = "Grenoble, France",
Editor = "A. Bouajjani and O. Maler",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 5643,
Pages = "627--633",
Year = 2009,
ISBN = "978-3-642-02657-7",
Abstract = "Static analysis by abstract interpretation [1] aims it
automatically inferring properties on the behaviour of
programs. We focus here on a specific kind of numerical
invariants: the set of values taken by numerical
variables, with a real numbers semantics, at each
control point of a program."
}
@Incollection{KimGR07,
Author = "D. Kim and G. Gupta and S. V. Rajopadhye",
Title = "On Control Signals for Multi-Dimensional Time",
Booktitle = "Languages and Compilers for Parallel Computing",
Editor = "G. Alm{\'a}si and C. Ca\c{s}caval and P. Wu",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Year = 2007,
Volume = 4382,
Pages = "141--155",
ISBN = "978-3-540-72520-6",
Note = "Revised papers presented at the 19th International Workshop
on Languages and Compilers for Parallel Computing (LCPC 2006),
New Orleans, Louisiana, USA, November 2--4, 2006",
Abstract = "Affine control loops (ACLs) comprise an important class
of compute- and data-intensive computations. The
theoretical framework for the automatic parallelization
of ACLs is well established. However, the hardware
compilation of arbitrary ACLs is still in its
infancy. An important component for an efficient
hardware implementation is a control mechanism that
informs each processing element (PE) which computation
needs to be performed and when. We formulate this
\emph{control signal problem} in the context of
compiling arbitrary ACLs parallelized with a
multi-dimensional schedule into hardware. We
characterize the logical time instants when PEs need a
control signal indicating which particular computations
need to be performed. Finally, we present an algorithm
to compute the minimal set of logical time instants for
these control signals."
}
@Inproceedings{KopfE13,
Author = "B. K{\"o}pf and A. Rybalchenko ",
Title = "Automation of Quantitative Information-Flow Analysis",
Booktitle = "Formal Methods for Dynamical Systems:
13th International School on Formal Methods for
the Design of Computer, Communication, and Software Systems
(SFM 2013)",
Address = "Bertinoro, Italy",
Series = "Lecture Notes in Computer Science",
Editor = "M. Bernardo and E. de Vink and A. Di Pierro and H. Wiklicky",
Publisher = "Springer-Verlag, Berlin",
ISBN = "7938",
Pages = "1--28",
Volume = 7938,
Year = 2013,
Abstract = "Quantitative information-flow analysis (QIF) is an
emerging technique for establishing
information-theoretic confidentiality
properties. Automation of QIF is an important step
towards ensuring its practical applicability, since
manual reasoning about program security has been shown
to be a tedious and expensive task. In this chapter we
describe a approximation and randomization techniques to
bear on the challenge of sufficiently precise, yet
efficient computation of quantitative information flow
properties."
}
@Inproceedings{KruegelKMRV05,
Author = "C. Kruegel and E. Kirda and D. Mutz and W. Robertson and G. Vigna",
Title = "Automating Mimicry Attacks Using Static Binary Analysis",
Booktitle = "Proceedings of Security~'05,
the 14th USENIX Security Symposium",
Address = "Baltimore, MD, USA",
Year = 2005,
Pages = "161--176",
Abstract = "Intrusion detection systems that monitor sequences of
system calls have recently become more sophisticated in
defining legitimate application behavior. In particular,
additional information, such as the value of the program
counter and the configuration of the program's call
stack at each system call, has been used to achieve
better characterization of program behavior. While there
is common agreement that this additional information
complicates the task for the attacker, it is less clear
to which extent an intruder is constrained.
In this paper, we present a novel technique to evade the
extended detection features of state-of-the-art
intrusion detection systems and reduce the task of the
intruder to a traditional mimicry attack. Given a
legitimate sequence of system calls, our technique
allows the attacker to execute each system call in the
correct execution context by obtaining and relinquishing
the control of the application's execution flow through
manipulation of code pointers.
We have developed a static analysis tool for Intel x86
binaries that uses symbolic execution to automatically
identify instructions that can be used to redirect
control flow and to compute the necessary modifications
to the environment of the process. We used our tool to
successfully exploit three vulnerable programs and evade
detection by existing state-of-the-art system call
monitors. In addition, we analyzed three real-world
applications to verify the general applicability of our
techniques."
}
@Inproceedings{LagoonMS03,
Author = "V. Lagoon and F. Mesnard and P. J. Stuckey",
Title = "Termination Analysis with Types Is More Accurate",
Booktitle = "Logic Programming: Proceedings of the
19th International Conference (ICLP 2003)",
Address = "Mumbai, India",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 2916,
Year = 2003,
Pages = "254--268",
Abstract = "In this paper we show how we can use size and groundness
analyses lifted to regular and (polymorphic)
Hindley/Milner typed programs to determine more accurate
termination of (type correct) programs. Type information
for programs may be either inferred automatically or
declared by the programmer. The analysis of the typed
logic programs is able to completely reuse a framework
for termination analysis of untyped logic programs by
using abstract compilation of the type abstraction. We
show that our typed termination analysis is uniformly
more accurate than untyped termination analysis for
regularly typed programs, and demonstrate how it is able
to prove termination of programs which the untyped
analysis can not."
}
@Article{LarsenLTW13,
Author = "K. G. Larsen and A. Legay and L.-M. Traonouez and A. Wasowski",
Title = "Robust Synthesis for Real-Time Systems",
Journal = "Theoretical Computer Science",
Publisher = "Elsevier",
Volume = 515,
Pages = "96--122",
Year = 2013,
Abstract = "Specification theories for real-time systems allow
reasoning about interfaces and their implementation
models, using a set of operators that includes
satisfaction, refinement, logical and parallel
composition. To make such theories applicable throughout
the entire design process from an abstract specification
to an implementation, we need to reason about the
possibility to effectively implement the theoretical
specifications on physical systems, despite their
limited precision. In the literature, this
implementation problem has been linked to the robustness
problem that analyzes the consequences of introducing
small perturbations into formal models."
}
@Inproceedings{LavironL09,
Author = "V. Laviron and F. Logozzo",
Title = "SubPolyhedra: A (More) Scalable Approach to Infer Linear
Inequalities",
Booktitle = "Verification, Model Checking, and Abstract Interpretation:
Proceedings of the 10th International Conference (VMCAI 2009)",
Address = "Savannah, Georgia, USA",
Editor = "N. D. Jones and M. M{\"u}ller-Olm",
Pages = "229--244",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 5403,
Year = 2009,
ISBN = "978-3-540-93899-6",
Abstract = "We introduce Subpolyhedra (\textsf{SubPoly}) a new
numerical abstract domain to infer and propagate linear
inequalities. \textsf{SubPoly} is as expressive as
Polyhedra, but it drops some of the deductive power to
achieve scalability. \textsf{SubPoly} is based on the
insight that the reduced product of linear equalities
and intervals produces powerful yet scalable analyses.
Precision can be recovered using hints. Hints can be
automatically generated or provided by the user in the
form of annotations. We implemented \textsf{SubPoly} on
the top of \texttt{Clousot}, a generic abstract
interpreter for \texttt{.Net}. \texttt{Clousot} with
\textsf{SubPoly} analyzes very large and complex code
bases in few minutes. \textsf{SubPoly} can efficiently
capture linear inequalities among hundreds of variables,
a result well-beyond state-of-the-art implementations of
Polyhedra."
}
@Inproceedings{LeconteB06,
Author = "M. Leconte and B. Berstel",
Title = "Extending a {CP} Solver with Congruences
as Domains for Program Verification",
Booktitle = "Proceedings of the 1st workshop on Constraints
in Software Testing, Verification and Analysis (CSTVA '06)",
Address = "Nantes, France",
Editor = "B. Blanc and A. Gotlieb and C. Michel",
Publisher = "IEEE Computer Society Press",
Pages = "22--33",
Year = 2006,
Abstract = "Constraints generated for Program Verification tasks
very often involve integer variables ranging on all the
machine-representable integer values. Thus, if the
propagation takes a time that is linear in the size of
the domains, it will not reach a fix point in practical
time. Indeed, the propagation time needed to reduce the
interval domains for as simple equations as $x = 2y + 1$
and $x = 2z$ is proportional to the size of the initial
domains of the variables. To avoid this \emph{slow
convergence} phenomenon, we propose to enrich a
Constraint Programming Solver (CP Solver) with
\emph{congruence domains}. This idea has been introduced
by [Granger, P.: Static analysis of arithmetic congruences.
International Journal of Computer Math (1989) 165--199]
in the abstract interpretation community and we show how
a CP Solver can benefit from it, for example in
discovering immediately that $12x + |y| = 3$ and
$4z + 7y = 0$ have no integer solution.",
Note = "Available at
\url{http://www.irisa.fr/manifestations/2006/CSTVA06/}."
}
@Inproceedings{LimeRST09,
Author = "D. Lime and O. H. Roux and C. Seidner and L.-M. Traonouez",
Title = "Romeo: A Parametric Model-Checker for {Petri} Nets
with Stopwatches",
Booktitle = "Proceedings of the 15th International Conference
Tools and Algorithms for the Construction and Analysis
of Systems (TACAS 2009)",
Address = "York, UK",
Editor = "S. Kowalewski and A. Philippou",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 5505,
Pages = "54--57",
Year = 2009,
ISBN = "978-3-642-00767-5",
Abstract = "Last time we reported on Romeo, analyses with this tool
were mostly based on translations to other tools. This
new version provides an integrated TCTL model-checker
and has gained in expressivity with the addition of
parameters. Although there exists other tools to compute
the state-space of stopwatch models, Romeo is the first
one that performs TCTL model-checking on stopwatch
models. Moreover, it is the first tool that performs
TCTL model-checking on timed parametric models. Indeed,
Romeo now features an efficient model-checking of time
Petri nets using the Uppaal DBM Library, the
model-checking of stopwatch Petri nets and parametric
stopwatch Petri nets using the Parma Polyhedra Library
and a graphical editor and simulator of these
models. Furthermore, its audience has increased leading
to several industrial contracts. This paper reports on
these recent developments of Romeo."
}
@Article{LimeMR13,
Author = "D. Lime and C. Martinez and O. H. Roux",
Title = "Shrinking of Time Petri nets",
Journal = "Discrete Event Dynamic Systems",
Publisher = "Springer-Verlag, Berlin",
Volume = 23,
Number = 4,
Pages = "419--438",
Year = 2013,
ISSN = "0924-6703 (Print) 1573-7594 (Online)",
Abstract = "The problem of the synthesis of time bounds enforcing
good properties for reactive systems has been much
studied in the literature. These works mainly rely on
dioid algebra theory and require important restrictions
on the structure of the model (notably by restricting to
timed event graphs). In this paper, we address the
problems of existence and synthesis of shrinkings of the
bounds of the time intervals of a time Petri net, such
that a given property is verified. We show that this
problem is decidable for CTL properties on bounded time
Petri nets. We then propose a symbolic algorithm based
on the state class graph for a fragment of CTL. If the
desired property ``include'' k-boundedness, the proposed
algorithm terminates even if the net is unbounded. A
prototype has been implemented in our tool Romeo and the
method is illustrated on a small case study from the
literature."
}
@Inproceedings{LogozzoF08,
Author = "F. Logozzo and M. F{\"a}hndrich",
Title = "Pentagons: A Weakly Relational Abstract Domain for the
Efficient Validation of Array Accesses",
Booktitle = "Proceedings of the 2008 ACM Symposium on Applied Computing
(SAC 2008)",
Address = "Fortaleza, Cear\'a, Brazil",
Aditor = "R. L. Wainwright and H. Haddad",
Year = 2008,
Pages = "184--188",
Publisher = "ACM Press",
ISBN = "978-1-59593-753-7",
Abstract = "We introduce Pentagons (\textsf{Pntg}), a weakly
relational numerical abstract domain useful for the
validation of array accesses in byte-code and
intermediate languages (IL). This abstract domain
captures properties of the form of
$x \in [a. b] \wedge x < y$. It is more precise than the
well known Interval domain, but it is less precise than
the Octagon domain. The goal of \textsf{Pntg} is to be
a lightweight numerical domain useful for adaptive
static analysis, where \textsf{Pntg} is used to quickly
prove the safety of most array accesses, restricting the
use of more precise (but also more expensive) domains to
only a small fraction of the code. We implemented the
\textsf{Pntg} abstract domain in \texttt{Clousot}, a
generic abstract interpreter for .NET assemblies. Using
it, we were able to validate 83\% of array accesses in
the core runtime library \texttt{mscorlib.dll} in less
than 8 minutes."
}
@Inproceedings{MakhloufK06,
Author = "I. B. Makhlouf and S. Kowalewski",
Title = "An Evaluation of Two Recent Reachability Analysis Tools
for Hybrid Systems",
Booktitle = "Proceedings of the 2nd IFAC Conference on Analysis
and Design of Hybrid Systems",
Address = "Alghero, Italy",
Editor = "C. Cassandras and A. Giua and C. Seatzu and J. Zaytoon",
Publisher = "Elsevier Science B.V.",
Year = 2006,
Abstract = "The hybrid systems community is still struggling to
provide practically applicable verification
tools. Recently, two new tools, PHAVer and Hsolver, were
introduced which promise to be a further step in this
direction. We evaluate and compare both tools with the
help of several benchmark examples. The results show
that both have their strengths and weaknesses, and that
there still is no all-purpose reachability analysis tool
for hybrid systems."
}
@Inproceedings{ManevichSRF04,
Author = "R. Manevich and M. Sagiv and G. Ramalingam and J. Field",
Title = "Partially Disjunctive Heap Abstraction",
Booktitle = "Static Analysis:
Proceedings of the 11th International Symposium",
Address = "Verona, Italy",
Editor = "R. Giacobazzi",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 3148,
Year = 2004,
Pages = "265--279",
Abstract = "One of the continuing challenges in abstract
interpretation is the creation of abstractions that
yield analyses that are both tractable and precise
enough to prove interesting properties about real-world
programs. One source of difficulty is the need to handle
programs with different behaviors along different
execution paths. Disjunctive (powerset) abstractions
capture such distinctions in a natural way. However, in
general, powerset abstractions increase the space and
time by an exponential factor. Thus, powerset
abstractions are generally perceived as being very
costly. In this paper we partially address this
challenge by presenting and empirically evaluating a new
heap abstraction. The new heap abstraction works by
merging shape descriptors according to a partial
isomorphism similarity criteria, resulting in a
partially disjunctive abstraction. We implemented this
abstraction in TVLA --- a generic system for
implementing program analyses. We conducted an empirical
evaluation of the new abstraction and compared it with
the powerset heap abstraction. The experiments show that
analyses based on the partially disjunctive abstraction
are as precise as the ones based on the fully
disjunctive abstraction. In terms of performance,
analyses based on the partially disjunctive abstraction
are often superior to analyses based on the fully
disjunctive heap abstraction. The empirical results show
considerable speedups, up to 2 orders of magnitude,
enabling previously non-terminating analyses, such as
verification of the Deutsch-Schorr-Waite marking
algorithm, to terminate with no negative effect on the
overall precision. Indeed, experience indicates that the
partially disjunctive shape abstraction improves
performance across all TVLA analyses uniformly, and in
many cases is essential for making precise shape
analysis feasible."
}
@Techreport{McCloskeyS09TR,
Author = "B. McCloskey and M. Sagiv",
Title = "Combining Quantified Domains",
Number = "EECS-2009-106",
Year = 2009,
Month = jul,
Institution = "EECS Department University of California",
Address = "Berkeley USA",
URL = "http://www.eecs.berkeley.edu/Pubs/TechRpts/2009/EECS-2009-106.pdf",
Abstract = "We develop general algorithms for reasoning about
numerical properties of programs manipulating the heap
via pointers. We automatically infer quantified
invariants regarding unbounded sets of memory locations
and unbounded numeric values. As an example, we can
infer that for every node in a data structure, the
node's length field is less than its capacity field. We
can also infer per-node statements about cardinality,
such as that each node's count field is equal to the
number of elements reachable from it. This additional
power allows us to prove properties about reference
counted data structures and B-trees that were previously
unattainable. Besides the ability to verify more
programs, we believe that our work sheds new light on
the interaction between heap and numerical reasoning.
Our algorithms are parametric in the heap and the
numeric abstractions. They permit heap and numerical
abstractions to be combined into a single abstraction
while maintaining correlations between these
abstractions. In certain combinations not involving
cardinality, we prove that our combination technique is
complete, which is surprising in the presence of
quantification."
}
@PhdThesis{Meijer10th,
Author = "S. Meijer",
Title = "Transformations for Polyhedral Process Networks",
School = "Leiden Institute of Advanced Computer Science (LIACS),
Faculty of Science, Leiden University",
Address = "Leiden, The Netherlands",
Year = 2010,
ISBN = "978-90-9025792-1",
Abstract = "We use the polyhedral process network (PPN) model of
computation to program and map streaming applications
onto embedded Multi-Processor Systems on Chip (MPSoCs)
platforms. The PPNs, which can be automatically derived
from sequential program applications, do not necessarily
meet the performance/resource constraints. A designer
can therefore apply the process splitting
transformations to increase program performance, and the
process merging transformation to reduce the number of
processes in a PPN. These transformations were defined,
but a designer had many possibilities to apply a
particular transformation, and these transformations can
also be ordered in many different ways. In this
dissertation, we define compile-time solution approaches
that assist the designer in evaluating and applying
process splitting and merging transformations in the
most effective way."
}
@Article{MesnardB05TPLP,
Author = "F. Mesnard and R. Bagnara",
Title = "{cTI}: A Constraint-Based Termination Inference Tool
for {ISO-Prolog}",
Journal = "Theory and Practice of Logic Programming",
Publisher = "Cambridge University Press",
Address = "New York",
Volume = 5,
Number = "1{\&}2",
Pages = "243--257",
Year = 2005,
Abstract = "We present cTI, the first system for universal
left-termination inference of logic programs.
Termination inference generalizes termination analysis
and checking. Traditionally, a termination analyzer
tries to prove that a given class of queries terminates.
This class must be provided to the system, for instance
by means of user annotations. Moreover, the analysis
must be redone every time the class of queries of
interest is updated. Termination inference, in
contrast, requires neither user annotations nor
recomputation. In this approach, terminating classes
for all predicates are inferred at once. We describe
the architecture of cTI and report an extensive
experimental evaluation of the system covering many
classical examples from the logic programming
termination literature and several Prolog programs of
respectable size and complexity."
}
@Inproceedings{MonniauxG11,
Author = "D. Monniaux and J. {Le Guen}",
Title = "Stratified Static Analysis Based on Variable Dependencies",
Booktitle = "Proceedings of the Third International Workshop on
Numerical and Symbolic Abstract Domains (NSAD 2011)",
Address = "Venice, Italy",
Year = 2011,
URL = "http://arxiv.org/abs/1109.2405",
Abstract = "In static analysis by abstract interpretation, one often
uses \emph{widening operators} in order to enforce
convergence within finite time to an inductive
invariant. Certain widening operators, including the
classical one over finite polyhedra, exhibit an
unintuitive behavior: analyzing the program over a
subset of its variables may lead a more precise result
than analyzing the original program! In this article, we
present simple workarounds for such behavior."
}
@Inproceedings{MihailaSS13b,
Author = "B. Mihaila and A. Sepp and A. Simon",
Title = "Widening as Abstract Domain",
Booktitle = "NASA Formal Methods:
Proceedings of the 5th International Symposium (NFM 2013)",
Editor = "G. Brat and N. Rungta and A. Venet",
Address = "Moffett Field, CA, USA",
Pages = "170--174",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 7871,
Year = 2013,
Abstract = "Verification using static analysis often hinges on
precise numeric invariants. Numeric domains of infinite
height can infer these invariants, but require
widening/narrowing which complicates the fixpoint
computation and is often too imprecise. As a
consequence, several strategies have been proposed to
prevent a precision loss during widening or to narrow in
a smarter way. Most of these strategies are difficult to
retrofit into an existing analysis as they either
require a pre-analysis, an on-the-fly modification of
the CFG, or modifications to the fixpoint algorithm. We
propose to encode widening and its various refinements
from the literature as cofibered abstract domains that
wrap standard numeric domains, thereby providing a
modular way to add numeric analysis to any static
analysis, that is, without modifying the fixpoint
engine. Since these domains cannot make any assumptions
about the structure of the program, our approach is
suitable to the analysis of executables, where the
(potentially irreducible) CFG is re-constructed
on-the-fly. Moreover, our domain-based approach not only
mirrors the precision of more intrusive approaches in
the literature but also requires fewer iterations to
find a fixpoint of loops than many heuristics that
merely aim for precision."
}
@Inproceedings{MoserKK07,
Author = "A. Moser and C. Kr{\"u}gel and E. Kirda",
Title = "Exploring Multiple Execution Paths for Malware Analysis",
Booktitle = "Proceedings of the 2007 IEEE Symposium on Security and Privacy
(S{\&}P 2007)",
Address = "Oakland, California, USA",
Publisher = "IEEE Computer Society Press",
Pages = "231--245",
Year = 2007,
Abstract = "Malicious code (or malware) is defined as software that
fulfills the deliberately harmful intent of an
attacker. Malware analysis is the process of determining
the behavior and purpose of a given malware sample (such
as a virus, worm, or Trojan horse). This process is a
necessary step to be able to develop effective detection
techniques and removal tools. Currently, malware
analysis is mostly a manual process that is tedious and
time-intensive. To mitigate this problem, a number of
analysis tools have been proposed that automatically
extract the behavior of an unknown program by executing
it in a restricted environment and recording the
operating system calls that are invoked. The problem of
dynamic analysis tools is that only a single program
execution is observed. Unfortunately, however, it is
possible that certain malicious actions are only
triggered under specific circumstances (e.g., on a
particular day, when a certain file is present, or when
a certain command is received). In this paper, we
propose a system that allows us to explore multiple
execution paths and identify malicious actions that are
executed only when certain conditions are met. This
enables us to automatically extract a more complete view
of the program under analysis and identify under which
circumstances suspicious actions are carried out. Our
experimental results demonstrate that many malware
samples show different behavior depending on input read
from the environment. Thus, by exploring multiple
execution paths, we can obtain a more complete picture
of their actions."
}
@Inproceedings{NavasMH09,
Author = "J. Navas and M. M{\'e}ndez-Lojo and M. V. Hermenegildo",
Title = "User-Definable Resource Usage Bounds Analysis for {Java} Bytecode",
Booktitle = "Proceedings of the 4th Workshop on Bytecode Semantics,
Verification, Analysis and Transformation (Bytecode 2009)",
Address = "York, UK",
Series = "Electronic Notes in Theoretical Computer Science",
Publisher = "Elsevier Science B.V.",
Volume = 253,
Number = 5,
Pages = "65--82",
Year = 2009,
ISSN = "1571-0661",
Abstract = "Automatic cost analysis of programs has been
traditionally concentrated on a reduced number of
resources such as execution steps, time, or
memory. However, the increasing relevance of analysis
applications such as static debugging and/or
certification of user-level properties (including for
mobile code) makes it interesting to develop analyses
for resource notions that are actually
application-dependent. This may include, for example,
bytes sent or received by an application, number of
files left open, number of SMSs sent or received, number
of accesses to a database, money spent, energy
consumption, etc. We present a fully automated analysis
for inferring upper bounds on the usage that a Java
bytecode program makes of a set of application
programmer-definable resources. In our context, a
resource is defined by programmer-provided annotations
which state the basic consumption that certain program
elements make of that resource. From these definitions
our analysis derives functions which return an upper
bound on the usage that the whole program (and
individual blocks) make of that resource for any given
set of input data sizes. The analysis proposed is
independent of the particular resource. We also present
some experimental results from a prototype
implementation of the approach covering a significant
set of interesting resources."
}
@Article{PanizoG12,
Author = "L. Panizo and M.-d.-M. Gallardo",
Title = "An extension of Java PathFinder for hybrid systems",
Booktitle = "ACM SIGSOFT Software Engineering Notes",
Volume = 37,
Number = 6,
Year = 2012,
ISSN = "0163-5948",
Pages = "1--5",
Publisher = "ACM New York, USA",
Abstract = "Hybrid systems are characterized by combining discrete
and continuous behaviors. Verification of hybrid systems
is, in general, a diffcult task due to the potential
complexity of the continuous dynamics. Currently, there
are different formalisms and tools which are able to
analyze specific types of hybrid systems, model checking
being one of the most used approaches. In this paper, we
describe an extension of Java PathFinder in order to
analyze hybrid systems. We apply a general methodology
which has been successfully used to extend Spin. This
methodology is non-intrusive, and uses external
libraries, such as the Parma Polyhedra Library, to
abstract the continuous behavior of the hybrid system."
}
@Inproceedings{PartushY13,
Author = "N. Partush and E. Yahav",
Title = "Abstract Semantic Differencing for Numerical Programs",
Booktitle = "Static Analysis:
Proceedings of the 20th International Symposium (SAS 2013)",
Address = "Seattle, WA, USA",
Editor = "F. Logozzo and M. F{\"a}hndrich",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 7935,
Pages = "238--258",
Year = 2013,
ISBN = "978-3-642-38855-2 (Print) 978-3-642-38856-9 (Online)",
Abstract = "We address the problem of computing semantic differences
between a program and a patched version of the
program. Our goal is to obtain a precise
characterization of the difference between program
versions, or establish their equivalence when no
difference exists.
We focus on computing semantic differences in numerical
programs where the values of variables have no a-priori
bounds, and use abstract interpretation to compute an
over-approximation of program differences. Computing
differences and establishing equivalence under
abstraction requires abstracting relationships between
variables in the two programs. Towards that end, we
first construct a correlating program in which these
relationships can be tracked, and then use a correlating
abstract domain to compute a sound approximation of
these relationships. To better establish equivalence
between correlated variables and precisely capture
differences, our domain has to represent non-convex
information using a partially-disjunctive abstract
domain. To balance precision and cost of this
representation, our domain over-approximates numerical
information while preserving equivalence between
correlated variables by dynamically partitioning the
disjunctive state according to equivalence criteria.
We have implemented our approach in a tool called DIZY,
and applied it to a number of real-world examples,
including programs from the GNU core utilities, Mozilla
Firefox and the Linux Kernel. Our evaluation shows that
DIZY often manages to establish equivalence, describes
precise approximation of semantic differences when
difference exists, and reports only a few false
differences."
}
@Inproceedings{CuervoParrinoNVM12,
Author = "B. {Cuervo Parrino} and J. Narboux and E. Violard and N. Magaud",
Title = "Dealing with Arithmetic Overflows in the Polyhedral Model",
Booktitle = "Proceedings of the 2nd International Workshop
on Polyhedral Compilation Techniques (IMPACT 2012)",
Address = "Paris, France",
Editor = "U. Bondhugula and V. Loechner ",
Year = 2012,
URL = "http://hal.inria.fr/hal-00655485",
Abstract = "The polyhedral model provides techniques to optimize
Static Control Programs (SCoP) using some complex
transforma- tions which improve data-locality and which
can exhibit parallelism. These advanced
transformations are now available in both GCC and
LLVM. In this paper, we focus on the cor- rectness of
these transformations and in particular on the problem
of integer overflows. Indeed, the strength of the
polyhedral model is to produce an abstract mathematical
representation of a loop nest which allows high-level
trans- formations. But this abstract representation is
valid only when we ignore the fact that our integers are
only machine integers. In this paper, we present a
method to deal with this problem of mismatch between the
mathematical and concrete representations of loop
nests. We assume the exis- tence of polyhedral
optimization transformations which are proved to be
correct in a world without overflows and we provide a
self-verifying compilation function. Rather than
verifying the correctness of this function, we use an
approach based on a validator, which is a tool that is
run by the com- piler after the transformation itself
and which confirms that the code produced is equivalent
to the original code. As we aim at the formal proof of
the validator we implement this validator using the Coq
proof assistant as a programming language [4]."
}
@Inproceedings{PayetS07,
Author = "E. Payet and F. Spoto",
Title = " Magic-Sets Transformation for the Analysis of {Java} Bytecode",
Booktitle = "Static Analysis:
Proceedings of the 14th International Symposium",
Address = "Kongens Lyngby, Denmark",
Editor = "G. Fil\'e and H. R. Nielson",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 4634,
ISBN = "978-3-540-74060-5",
Pages = "452--467",
Year = 2007,
Abstract = "Denotational static analysis of Java bytecode has a nice
and clean compositional definition and an efficient
implementation with binary decision diagrams. But it
models only the \emph{functional} i.e., input/output
behaviour of a program $P$, not enough if one needs $P$'s
\emph{internal} behaviours i.e., from the input to some
internal program points. We overcome this limitation
with a technique used up to now for logic programs
only. It adds new \emph{magic} blocks of code to P, whose
functional behaviours are the internal behaviours of
$P$. We prove this transformation correct with an
operational semantics. We define an equivalent
denotational semantics, whose denotations for the
magic blocks are hence the internal behaviours of
$P$. We implement our transformation and instantiate
it with abstract domains modelling \emph{sharing} of two
variables and \emph{non-cyclicity} of variables. We get a
static analyser for full Java bytecode that is
faster and scales better than another operational
pair-sharing analyser and a constraint-based pointer
analyser."
}
@Inproceedings{PerezRS09,
Author = "J. A. {Navarro P{\'e}rez} and A. Rybalchenko and A. Singh",
Title = "Cardinality Abstraction for Declarative Networking Applications",
Booktitle = "Computer Aided Verification:
Proceedings of the 21st International Conference (CAV 2009)",
Address = "Grenoble, France",
Editor = "A. Bouajjani and O. Maler",
Publisher = "Springer",
Series = "Lecture Notes in Computer Science",
Volume = 5643,
Pages = "584--598",
Year = 2009,
ISBN = "978-3-642-02657-7",
Abstract = "Declarative Networking is a recent, viable approach to
make distributed programming easier, which is becoming
increasingly popular in systems and networking
community. It offers the programmer a declarative,
rule-based language, called P2, for writing distributed
applications in an abstract, yet expressive way. This
approach, however, imposes new challenges on analysis
and verification methods when they are applied to P2
programs. Reasoning about P2 computations is beyond the
scope of existing tools since it requires handling of
program states defined in terms of collections of
relations, which store the application data, together
with multisets of tuples, which represent communication
events in-flight. In this paper, we propose a
cardinality abstraction technique that can be used to
analyze and verify P2 programs. It keeps track of the
size of relations (together with projections thereof)
and multisets defining P2 states, and provides an
appropriate treatment of declarative operations, e.g.,
indexing, unification, variable binding, and
negation. Our cardinality abstraction-based verifier
successfully proves critical safety properties of a P2
implementation of the Byzantine fault tolerance protocol
Zyzzyva, which is a representative and complex
declarative networking application."
}
@Inproceedings{PhamTTC11,
Author = "T.-H. Pham and M.-T. Trinh and A.-H. Truong and W.-N. Chin",
Title = "{FixBag:} A Fixpoint Calculator for Quantified Bag Constraints",
Booktitle = "Computer Aided Verification:
Proceedings of the 23rd International Conference (CAV 2011)",
Address = "Snowbird, UT, USA",
Series = "Lecture Notes in Computer Science",
Editor = "G. Gopalakrishnan and S. Qadeer",
Publisher = "Springer-Verlag, Berlin",
ISBN = "978-3-642-22109-5",
Pages = "656--662",
Volume = 6806,
Year = 2011,
Abstract = "Abstract interpretation techniques have played a major
role in advancing the state-of-the-art in program
analysis. Traditionally, stand-alone tools for these
techniques have been developed for the numerical domains
which may be sufficient for lower levels of program
correctness. To analyze a wider range of programs, we
have developed a tool to compute symbolic fixpoints for
quantified bag domain . This domain is useful for
programs that deal with collections of values. Our tool
is able to derive both loop invariants and method
pre/post conditions via fixpoint analysis of recursive
bag constraints. To support better precision, we have
allowed disjunctive formulae to be inferred, where
appropriate. As a stand-alone tool, we have tested it on
a range of small but challenging examples with
acceptable precision and performance."
}
@Techreport{Pop06,
Author = "S. Pop and G.-A. Silber and A. Cohen and C. Bastoul
and S. Girbal and N. Vasilache",
Title = "{GRAPHITE}: Polyhedral Analyses and Optimizations for {GCC}",
Number = "A/378/CRI",
Institution = "Centre de Recherche en Informatique,
\'Ecole des Mines de Paris",
Address = "Fontainebleau, France",
Year = 2006,
Note = "Contribution to the GNU Compilers Collection Developers Summit 2006
(GCC Summit 06), Ottawa, Canada, June 28--30, 2006",
Abstract = "We present a plan to add loop nest optimizations in GCC
based on polyhedral representations of loop nests. We
advocate a static analysis approach based on a hierarchy
of interchangeable abstractions with solvers that range
from the exact solvers such as OMEGA, to faster but less
precise solvers based on more coarse abstractions. The
intermediate representation GRAPHITE (GIMPLE Represented
as Polyhedra with Interchangeable Envelopes), built on
GIMPLE and the natural loops, hosts the high level loop
transformations. We base this presentation on the
WRaP-IT project developed in the Alchemy group at INRIA
Futurs and Paris-Sud University, on the PIPS compiler
developed at \'Ecole des mines de Paris, and on a joint
work with several members of the static analysis and
polyhedral compilation community in France.
The main goal of this project is to bring more high
level loop optimizations to GCC: loop fusion, tiling,
strip mining, etc. Thanks to the WRaP-IT experience, we
know that the polyhedral analyzes and transformations
are affordable in a production compiler. A second goal
of this project is to experiment with compile time
reduction versus attainable precision when replacing
operations on polyhedra with faster operations on more
abstract domains. However, the use of a too coarse
representation for computing might also result in an
over approximated solution that cannot be used in
subsequent computations. There exists a trade off
between speed of the computation and the attainable
precision that has not yet been analyzed for real world
programs."
}
@Incollection{PopeeaC08,
Author = "C. Popeea and W.-N. Chin",
Title = "Inferring Disjunctive Postconditions",
Booktitle = "Advances in Computer Science --- ASIAN 2006. Secure Software
and Related Issues",
Editor = "M. Okada and I. Satoh",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Year = 2008,
Volume = 4435,
Pages = "331--345",
ISBN = "978-3-540-77504-1",
Note = "Revised selected papers presented at the 11th Asian Computing
Science Conference, Tokyo, Japan, December 6--8, 2006",
Abstract = "Polyhedral analysis [9] is an abstract interpretation
used for automatic discovery of invariant linear
inequalities among numerical variables of a
program. Convexity of this abstract domain allows
efficient analysis but also loses precision via
convex-hull and widening operators. To selectively
recover the loss of precision, sets of polyhedra
(disjunctive elements) may be used to capture more
precise invariants. However a balance must be struck
between precision and cost.
We introduce the notion of affinity to characterize how
closely related is a pair of polyhedra. Finding related
elements in the polyhedron (base) domain allows the
formulation of precise hull and widening operators
lifted to the disjunctive (powerset extension of the)
polyhedron domain. We have implemented a modular static
analyzer based on the disjunctive polyhedral analysis
where the relational domain and the proposed operators
can progressively enhance precision at a reasonable
cost."
}
@Article{RizkBFS09,
Author = "A. Rizk and G. Batt and F. Fages and S. Soliman",
Title = "A General Computational Method for Robustness Analysis
with Applications to Synthetic Gene Networks",
Journal = "Bioinformatics",
Publisher = "Oxford University Press",
Volume = 25,
Number = "12",
Pages = "i169--i178",
Year = 2009,
Note = "Paper accepted for presentation at the 2009 ISMB/ECCB Conference,
Stockholm, Sweden, June 27--July 2, 2009.
Available at
\url{http://bioinformatics.oxfordjournals.org/cgi/content/abstract/25/12/i169}",
Abstract = "\textbf{Motivation:} Robustness is the capacity of a
system to maintain a function in the face of
perturbations. It is essential for the correct
functioning of natural and engineered biological
systems. Robustness is generally defined in an \emph{ad hoc},
problem-dependent manner, thus hampering the fruitful
development of a theory of biological robustness,
recently advocated by Kitano.
\textbf{Results:} In this article, we propose a general
definition of robustness that applies to any biological
function expressible in temporal logic LTL (linear
temporal logic), and to broad model classes and
perturbation types. Moreover, we propose a computational
approach and an implementation in BIOCHAM 2.8 for the
automated estimation of the robustness of a given
behavior with respect to a given set of
perturbations. The applicability and biological relevance
of our approach is demonstrated by testing and improving
the robustness of the timed behavior of a synthetic
transcriptional cascade that could be used as a
biological timer for synthetic biology applications.
\textbf{Availability:} Version 2.8 of BIOCHAM and the
transcriptional cascade model are available at
\url{http://contraintes.inria.fr/BIOCHAM/}"
}
@Article{RizkBFS11,
Author = "A. Rizk and G. Batt and F. Fages and S. Soliman",
Title = "Continuous Valuations of Temporal Logic Specifications with
Applications to Parameter Optimization and Robustness
Measures",
Journal = "Theoretical Computer Science",
Publisher = "Elsevier",
Volume = 412,
Number = 26,
Pages = "2827--2839",
Year = 2011,
ISSN = "0304-3975",
Abstract = "Finding mathematical models satisfying a specification
built from the formalization of biological experiments,
is a common task of the modeler that techniques like
model-checking help solving, in the qualitative but also
in the quantitative case. In this article we define a
continuous degree of satisfaction of temporal logic
formulae with constraints. We show how such a
satisfaction measure can be used as a fitness function
with state-of-the-art evolutionary optimization methods
in order to find biochemical kinetic parameter values
satisfying a set of biological properties formalized in
temporal logic. We also show how it can be used to
define a measure of robustness of a biological model
with respect to some temporal specification. These
methods are evaluated on models of the cell cycle and of
the MAPK signaling cascade."
}
@Inproceedings{SankaranarayananIG07,
Author = "S. Sankaranarayanan and F. Ivancic and A. Gupta",
Title = "Program Analysis Using Symbolic Ranges",
Booktitle = "Static Analysis:
Proceedings of the 14th International Symposium",
Address = "Kongens Lyngby, Denmark",
Editor = "G. Fil\'e and H. R. Nielson",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 4634,
ISBN = "978-3-540-74060-5",
Pages = "366--383",
Year = 2007,
Abstract = "Interval analysis seeks static lower and upper bounds on
the values of program variables. These bounds are
useful, especially for inferring invariants to prove buffer
overflow checks. In practice, however, intervals by
themselves are often inadequate as invariants due to the
lack of relational information among program variables.
In this paper, we present a technique for deriving symbolic
bounds on variable values. We study a restricted class of
polyhedra whose constraints are stratified with respect to
some variable ordering provided by the user, or chosen
heuristically. We define a notion of normalization for
such constraints and demonstrate polynomial time domain
operations on the resulting domain of symbolic range
constraints. The abstract domain is intended to complement
widely used domains such as intervals and octagons
for use in buffer overflow analysis. Finally, we study
the impact of our analysis on commercial software using
an overflow analyzer for the C language."
}
@Inproceedings{SankaranarayananSM04,
Author = "S. Sankaranarayanan and H. B. Sipma and Z. Manna",
Title = "Constraint-Based Linear-Relations Analysis",
Booktitle = "Static Analysis:
Proceedings of the 11th International Symposium",
Address = "Verona, Italy",
Editor = "R. Giacobazzi",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 3148,
Year = 2004,
Pages = "53--68",
Abstract = "Linear-relations analysis of transition systems
discovers linear invariant relationships among the
variables of the system. These relationships help
establish important safety and liveness
properties. Efficient techniques for the analysis of
systems using polyhedra have been explored, leading to
the development of successful tools like
HyTech. However, existing techniques rely on the use of
approximations such as widening and extrapolation in
order to ensure termination. In an earlier paper, we
demonstrated the use of Farkas' Lemma to provide a
translation from the linear-relations analysis problem
into a system of constraints on the unknown coefficients
of a candidate invariant. However, since the constraints
in question are non-linear, a naive application of the
method does not scale. In this paper, we show that by
some efficient simplifications and approximations to the
quantifier elimination, not only does the method scale
to higher dimensions, but also enjoys performance
advantages for some larger examples."
}
@Inproceedings{SankaranarayananSM05,
Author = "S. Sankaranarayanan and H. B. Sipma and Z. Manna",
Title = "Scalable Analysis of Linear Systems using Mathematical Programming",
Booktitle = "Verification, Model Checking and Abstract Interpretation:
Proceedings of the 6th International Conference (VMCAI 2005)",
Address = "Paris, France",
Editor = "R. Cousot",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 3385,
Year = 2005,
Pages = "25--41",
Abstract = "We present a method for generating linear invariants for
large systems. The method performs forward propagation
in an abstract domain consisting of arbitrary polyhedra
of a predefined fixed shape. The basic operations on the
domain like abstraction, intersection, join and
inclusion tests are all posed as linear optimization
queries, which can be solved efficiently by existing LP
solvers. The number and dimensionality of the LP queries
are polynomial in the program dimensionality, size and
the number of target invariants. The method generalizes
similar analyses in the interval, octagon, and octahedra
domains, without resorting to polyhedral
manipulations. We demonstrate the performance of our
method on some benchmark programs."
}
@Inproceedings{SankaranarayananCSM06,
Author = "S. Sankaranarayanan and M. Col{\'o}n
and H. B. Sipma and Z. Manna",
Title = "Efficient Strongly Relational Polyhedral Analysis",
Booktitle = "Verification, Model Checking and Abstract Interpretation:
Proceedings of the 7th International Conference (VMCAI 2006)",
Address = "Charleston, SC, USA",
Editor = "E. A. Emerson and K. S. Namjoshi",
Pages = "111--125",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 3855,
Year = 2006,
ISBN = "3-540-31139-4",
Abstract = "Polyhedral analysis infers invariant linear equalities
and inequalities of imperative programs. However, the
exponential complexity of polyhedral operations such as
image computation and convex hull limits the
applicability of polyhedral analysis. Weakly relational
domains such as intervals and octagons address the
scalability issue by considering polyhedra whose
constraints are drawn from a restricted, user-specified
class. On the other hand, these domains rely solely on
candidate expressions provided by the user. Therefore,
they often fail to produce strong invariants. We
propose a polynomial time approach to strongly
relational analysis. We provide efficient
implementations of join and post condition operations,
achieving a trade off between performance and
accuracy. We have implemented a strongly relational
polyhedral analyzer for a subset of the C
language. Initial experimental results on benchmark
examples are encouraging."
}
@Inproceedings{SankaranarayananSM06,
Author = "S. Sankaranarayanan and H. B. Sipma and Z. Manna",
Title = "Fixed Point Iteration for Computing the Time Elapse Operator",
Booktitle = "Hybrid Systems: Computation and Control:
Proceedings of the 9th International Workshop (HSCC 2006)",
Address = "Santa Barbara, CA, USA",
Editor = "J. Hespanha and A. Tiwari",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 3927,
Pages = "537--551",
Year = 2006,
ISBN = "3-540-33170-0",
Abstract = "We investigate techniques for automatically generating
symbolic approximations to the time solution of a system
of differential equations. This is an important
primitive operation for the safety analysis of
continuous and hybrid systems. In this paper we design a
\emph{time elapse} operator that computes a symbolic
over-approximation of time solutions to a continuous
system starting from a given initial region. Our
approach is iterative over the cone of functions (drawn
from a suitable universe) that are non negative over the
initial region. At each stage, we iteratively remove
functions from the cone whose Lie derivatives do not lie
inside the current iterate. If the iteration converges,
the set of states defined by the final iterate is shown
to contain all the time successors of the initial
region. The convergence of the iteration can be forced
using abstract interpretation operations such as
widening and narrowing. We instantiate our technique to
linear hybrid systems with piecewise-affine dynamics to
compute polyhedral approximations to the time
successors. Using our prototype implementation TimePass,
we demonstrate the performance of our technique on
benchmark examples."
}
@Inproceedings{SankaranarayananISG06,
Author = "S. Sankaranarayanan and F. Ivan\v{c}i\'{c}
and I. Shlyakhter and A. Gupta",
Title = "Static Analysis in Disjunctive Numerical Domains",
Booktitle = "Static Analysis:
Proceedings of the 13th International Symposium",
Address = "Seoul, Korea",
Editor = "K. Yi",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 4134,
Pages = "3--17",
Year = 2006,
ISBN = "3-540-37756-5",
Abstract = "The convexity of numerical domains such as polyhedra,
octagons, intervals and linear equalities enables
tractable analysis of software for buffer overflows,
null pointer dereferences and floating point
errors. However, convexity also causes the analysis to
fail in many common cases. Powerset extensions can
remedy this shortcoming by considering disjunctions of
predicates. Unfortunately, analysis using powerset
domains can be exponentially more expensive as compared
to analysis on the base domain. In this paper, we prove
structural properties of fixed points computed in
commonly used powerset extensions. We show that a fixed
point computed on a powerset extension is also a fixed
point in the base domain computed on an ``elaboration''
of the program's CFG structure. Using this insight, we
build analysis algorithms that approach path sensitive
static analysis algorithms by performing the fixed point
computation on the base domain while discovering an
``elaboration'' on the fly. Using restrictions on the
nature of the elaborations, we design algorithms that
scale polynomially in terms of the number of
disjuncts. We have implemented a light-weight static
analyzer for C programs with encouraging initial
results."
}
@Article{SchrammelJ12,
Author = "P. Schrammel and B. Jeannet",
Title = "Applying Abstract Acceleration to (Co-)Reachability Analysis of Reactive Programs",
Journal = "Journal of Symbolic Computation",
Publisher = "Elsevier Science B.V.",
Volume = 47,
Number = 12,
Year = 2012,
Pages = "1512--1532",
Abstract = "We propose a new technique combining dynamic and static
analysis of programs to find linear invariants. We use a
statistical tool, called simple component analysis, to
analyze partial execution traces of a given program. We
get a new coordinate system in the vector space of
program variables, which is used to specialize numerical
abstract domains. As an application, we instantiate our
technique to interval analysis of simple imperative
programs and show some experimental evaluations."
}
@Inproceedings{SharmaGHAN13,
Author = "R. Sharma and S. Gupta and B. Hariharan and A. Aiken and AV. Nori",
Title = "Verification as Learning Geometric Concepts",
Booktitle = "Static Analysis:
Proceedings of the 20th International Symposium (SAS 2013)",
Address = "Seattle, USA",
Series = "Lecture Notes in Computer Science",
Editor = "F. Logozzo and M. F{\"a}hndrich",
Publisher = "Springer-Verlag, Berlin",
ISBN = "978-3-642-38855-2 (Print) 978-3-642-38856-9 (Online)",
Pages = "388--411",
Volume = 7935,
Year = 2013,
Abstract = "We formalize the problem of program verification as a
learning problem, showing that invariants in program
verification can be regarded as geometric concepts in
machine learning. Safety properties define bad states:
states a program should not reach. Program verification
explains why a program’s set of reachable states is
disjoint from the set of bad states. In Hoare Logic,
these explanations are predicates that form inductive
assertions. Using samples for reachable and bad states
and by applying well known machine learning algorithms
for classification, we are able to generate inductive
assertions. By relaxing the search for an exact proof to
classifiers, we obtain complexity theoretic
improvements. Further, we extend the learning algorithm
to obtain a sound procedure that can generate proofs
containing invariants that are arbitrary boolean
combinations of polynomial inequalities. We have
evaluated our approach on a number of challenging
benchmarks and the results are promising."
}
@Inproceedings{Simon10a,
Author = "A. Simon",
Title = "A Note on the Inversion Join for Polyhedral Analysis",
Booktitle = "Proceedings of the 2nd International Workshop on
Numerical and Symbolic Abstract Domains (NSAD 2010)",
Series = "Electronic Notes in Theoretical Computer Science",
Publisher = "Elsevier Science B.V.",
Volume = 267,
Pages = "115--126",
Year = 2010,
ISSN = "1571-0661",
Abstract = "Linear invariants are essential in many optimization and
verification tasks. The domain of convex polyhedra (sets
of linear inequalities) has the potential to infer all
linear relationships. Yet, it is rarely applied to
larger problems due to the join operation whose most
precise result is given by the convex hull of two
polyhedra which, in turn, may be of exponential
size. Recently, Sankaranarayanan et al. proposed an
operation called inversion join to efficiently
approximate the convex hull. While their proposal has an
ad-hoc flavour, we show that it is quite principled and,
indeed, complete for planar polyhedra and, for general
polyhedra, complete on over 70% of our benchmarks."
}
@Inproceedings{Simon10b,
Author = "A. Simon",
Title = "Speeding up Polyhedral Analysis by Identifying Common Constraints",
Booktitle = "Proceedings of the 2nd International Workshop on
Numerical and Symbolic Abstract Domains (NSAD 2010)",
Series = "Electronic Notes in Theoretical Computer Science",
Publisher = "Elsevier Science B.V.",
Volume = 267,
Pages = "127--138",
Year = 2010,
ISSN = "1571-0661",
Abstract = "Sets of linear inequalities are an expressive reasoning
tool for approximating the reachable states of a
program. However, the most precise way to join two
states is to calculate the convex hull of the two
polyhedra that are represented by the inequality sets,
an operation that is exponential in the dimension of the
polyhedra. We investigate how similarities in the two
input polyhedra can be exploited to improve the
performance of this costly operation. In particular, we
discuss how common equalities and certain inequalities
can be omitted from the calculation without affecting
the result. We expose a maximum of common equalities and
inequalities by converting the polyhedra into a normal
form and give experimental evidence of the merit of our
method."
}
@Inproceedings{SimonL10,
Author = "A. Simon and L. Chen",
Title = "Simple and Precise Widenings for {H-Polyhedra}",
Booktitle = "Proceedings of the 8th Asian Symposium
on the Programming Languages and Systems (APLAS 2010)",
Address = "Shanghai, China",
Series = "Lecture Notes in Computer Science",
Editor = "K. Ueda",
Publisher = "Springer-Verlag, Berlin",
ISBN = "978-3-642-17163-5",
Pages = "139--155",
Volume = 6461,
Year = 2010,
Abstract = "While the definition of the revised widening for
polyhedra is defined in terms of inequalities, most
implementations use the double description method as a
means to an efficient implementation. We show how
standard widening can be implemented in a simple and
efficient way using a normalized H -representation
(constraint-only) which has become popular in recent
approximations to polyhedral analysis. We then detail a
novel heuristic for this representation that is tuned
to capture linear transformations of the state space
while ensuring quick convergence for non-linear
transformations for which no precise linear invariants
exist."
}
@Techreport{SlaninaSSM07TR,
Author = "M. Slanina and S. Sankaranarayanan and H. B. Sipma and Z. Manna",
Title = "Controller Synthesis of Discrete Linear Plants Using Polyhedra",
Number = "REACT-TR-2007-01",
Institution = "Computer Science Department, Stanford University",
Address = "Stanford, California, USA",
Year = 2007,
Abstract = "We study techniques for synthesizing synchronous
controllers for affine plants with disturbances, based
on safety specifications. Our plants are modeled in
terms of discrete linear systems whose variables are
partitioned into system, control, and disturbance
variables. We synthesize non-blocking controllers that
satisfy a user-provided safety specification by means of
a fixed point iteration over the control precondition
state transformer. Using convex polyhedra to represent
sets of states, we present both precise and approximate
algorithms for computing control preconditions and
discuss strategies for forcing convergence of the
iteration. We present technique for automatically
deriving controllers from the result of the analysis,
and demonstrate our approach on examples."
}
@TechReport{Soffia08TR,
Author = "S. Soffia",
Title = "Definition and Implementation of a Points-To Analysis
for C-like Languages",
Institution = "Dipartimento di Matematica, Universit\`a di Parma, Italy",
Number = "arXiv:cs.PL/0810.0753",
Year = 2008,
Note = "Available from \url{http://arxiv.org/}",
Abstract = "The points-to problem is the problem of determining the
possible run-time targets of pointer variables and is
usually considered part of the more general aliasing
problem, which consists in establishing whether and when
different expressions can refer to the same memory address.
Aliasing information is essential to every tool that needs
to reason about the semantics of programs. However, due to
well-known undecidability results, for all interesting
languages that admit aliasing, the exact solution of
nontrivial aliasing problems is not generally computable.
This work focuses on approximated solutions to this problem
by presenting a store-based, flow-sensitive points-to
analysis, for applications in the field of automated software
verification. In contrast to software testing procedures,
which heuristically check the program against a finite set
of executions, the methods considered in this work are static
analyses, where the computed results are valid for all the
possible executions of the analyzed program. We present a
simplified programming language and its execution model;
then an approximated execution model is developed using the
ideas of abstract interpretation theory. Finally, the
soundness of the approximation is formally proved. The aim
of developing a realistic points-to analysis is pursued by
presenting some extensions to the initial simplified model
and discussing the correctness of their formulation.
This work contains original contributions to the issue of
points-to analysis, as it provides a formulation of a filter
operation on the points-to abstract domain and a formal proof
of the soundness of the defined abstract operations:
these, as far as we now, are lacking from the previous
literature."
}
@Inproceedings{Starynkevitch07,
Author = "B. Starynkevitch",
Title = "Multi-Stage Construction of a Global Static Analyzer",
Booktitle = "Proceedings of the 2007 {GCC} Developers' Summit",
Address = "Ottawa, Canada",
Pages = "143--151",
Year = 2007,
Abstract = "We describe ongoing work about global static analysis
for GCC4 within the GlobalGCC European project,
funded thru the ITEA Programme. The aim of this
work is to provide global (whole program) static
analysis, notably based upon abstract interpretation
and knowledge based techniques, within the GCC
compiler, targeted for analysis of medium sized C,
Fortran or C++ programs. This will facilitate the
adoption of GCC in the area of safetycritical
software development, by providing features found in
a few expensive commercial tools (PolySpace, AbsInt)
or research prototypes (Astree). In this
perspective, the emphasis is on the quality of
analysis, at the expense of much bigger compilation
times, without sacrificing scalability. Such
analysis can be used for several purposes:
statically compute some interesting properties of
the program at most control points (possibly
reporting them the user); provide clever,
contextual, warnings about possible hazards in the
user program (null pointer dereferences, zero
divide, conversion loss, out of bound array access,
\dots) while avoiding too much false alarms; enable
additional optimisations, like conditional
contextual constant folding, C++ method call
devirtualization, an other contextual optimizations.
The compiler's rich program manipulation
infrastructure facilitates the development of these
advanced analysis capabilities. To facilitate the
development high-level semantical analyses, a domain
specific language has been developped, and is
translated (thru C) into dynamically loaded code. It
uses the Parma Polyhedra Library (also used in the
GRAPHITE project) for relational analysis on scalars
and gives more expressivity to develop analaysis
algorithms. It permits multi-staged generation of
the specific analysis tailored to the analyzed
source code. Presenting this work at the 2007 GCC
summit will allow us to stress the importance of all
outputs of the compiler, not only object-code, and
to expose the complementary contribution of static
analyses and dynamic/instrumentation approaches like
mudflap."
}
@Inproceedings{SongCR06,
Author = "H. Song and K. J. Compton and W. C. Rounds",
Title = "{SPHIN:} A Model Checker for Reconfigurable Hybrid Systems
Based on {SPIN}",
Booktitle = "Proceedings of the 5th International Workshop on
Automated Verification of Critical Systems",
Address = "University of Warwick, UK",
Editor = "R. Lazic and R. Nagarajan",
Series = "Electronic Notes in Theoretical Computer Science",
Publisher = "Elsevier Science B.V.",
Volume = 145,
Pages = "167--183",
Year = 2006,
Abstract = "We present SPHIN, a model checker for reconfigurable
hybrid systems based on the model checker SPIN. We
observe that physical (analog) mobility can be modeled
in the same way as logical (discrete) mobility is
modeled in the $\pi$-calculus by means of channel name
passing. We chose SPIN because it supports channel name
passing and can model reconfigurations. We extend the
syntax of PROMELA and the verification algorithms based
on the expected semantics. We demonstrate the tool's
capabilities by modeling and verifying a reconfigurable
hybrid system."
}
@Inproceedings{TraonouezLR08,
Author = "L.-M. Traonouez and D. Lime and O. H. Roux",
Title = "Parametric Model-Checking of Time {Petri} Nets with Stopwatches
Using the State-Class Graph",
Booktitle = "Proceedings of the 6th International Conference on
Formal Modeling and Analysis of Timed Systems (FORMATS 2008)",
Editor = "F. Cassez and C. Jard",
Address = "Saint Malo, France",
Pages = "280--294",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 5215,
Year = 2008,
ISBN = "978-3-540-85777-8",
Abstract = "In this paper, we propose a new framework for the
parametric verification of time Petri nets with
stopwatches controlled by inhibitor arcs. We first
introduce an extension of time Petri nets with inhibitor
arcs (ITPNs) with temporal parameters. Then, we define a
symbolic representation of the parametric state space
based on the classical state class graph method. The
parameters of the model are embedded into the firing
domains of the classes, that are represented by convex
polyhedra. Finally, we propose semi-algorithms for the
parametric model-checking of a subset of parametric TCTL
formulae on ITPNs. We can thus generate the set of the
parameter valuations that satisfy the formulae."
}
@Article{TraonouezLR09,
Author = "L.-M. Traonouez and D. Lime and O. H. Roux",
Title = "Parametric Model-Checking of Stopwatch Petri Nets",
Journal = "Journal of Universal Computer Science",
Year = 2009,
Volume = 15,
Number = 17,
Pages = "3273--3304",
Abstract = "At the border between control and verification,
parametric verification can be used to synthesize
constraints on the parameters to ensure that a system
verifies given specifications. In this paper we propose
a new framework for the parametric verification of time
Petri nets with stopwatches. We first introduce a
parametric extension of time Petri nets with inhibitor
arcs (ITPNs) with temporal parameters and we define a
symbolic representation of the parametric state-space
based on the classical state-class graph method. Then,
we propose semi-algorithms for the parametric
modelchecking of a subset of parametric TCTL formulae on
ITPNs. These results have been implemented in the tool
Romeo and we illustrate them in a case-study based on a
scheduling problem.", } Abstract: At the border between
control and verification, parametric verification can be
used to synthesize constraints on the parameters to
ensure that a system verifies given specifications. In
this paper we propose a new framework for the parametric
verification of time Petri nets with stopwatches. We
first introduce a parametric extension of time Petri
nets with inhibitor arcs (ITPNs) with temporal
parameters and we define a symbolic representation of
the parametric state-space based on the classical
state-class graph method. Then, we propose
semi-algorithms for the parametric modelchecking of a
subset of parametric TCTL formulae on ITPNs. These
results have been implemented in the tool Romeo and we
illustrate them in a case-study based on a scheduling
problem."
}
@Inproceedings{TrifunovicCEFG+10,
Author = "K. Trifunovic and A. Cohen and D. Edelsohn and L. Feng
and T. Grosser and H. Jagasia and R. Ladelsky and S. Pop
and J. Sj{\"o}din and R. Upadrasta",
Title = "{GRAPHITE} Two Years After:
First Lessons Learned From Real-World Polyhedral Compilation",
Booktitle = "Proceedings of the 2nd International Workshop on
GCC Research Opportunities (GROW'10)",
Address = "Pisa, Italy",
Year = 2010,
Pages = "4--19",
Abstract = "Modern compilers are responsible for adapting the
semantics of source programs into a form that makes
efficient use of a highly complex, heterogeneous
machine. This adaptation amounts to solve an
optimization problem in a huge and unstructured search
space, while predicting the performance outcome of
complex sequences of program transformations. The
polyhedral model of compilation is aimed at these
challenges. Its geometrical, non-inductive semantics
enables the construction of better-structured
optimization problems and precise analytical
models. Recent work demonstrated the scalability of the
main polyhedral algorithms to real-world programs. Its
integration into production compilers is under way,
pioneered by the graphite branch of the GNU Compiler
Collection (GCC). Two years after the effective
beginning of the project, this paper reports on original
questions and innovative solutions that arose during the
design and implementation of \textsc{graphite}."
}
@Techreport{UchoaFLPPdAA06TR,
Author = "E. Uchoa and R. Fukasawa and J. Lysgaard and A. Pessoa
and M. {Poggi de Arag\~ao} and D. Andrade",
Title = "Robust Branch-Cut-and-Price for the Capacitated
Minimum Spanning Tree Problem over a Large Extended Formulation",
Number = "RPEP, Vol.~6, No.~9",
Institution = "Universidade Federal Fluminense, Engenharia de Produ\c{c}ao",
Address = "Niteroi, Brazil",
Year = 2006,
Abstract = "This paper presents a robust branch-cut-and-price
algorithm for the Capacitated Minimum Spanning Tree
Problem (CMST). The variables are associated to
$q$-arbs, a structure that arises from a relaxation of
the capacitated prize-collecting arborescence probem in
order to make it solvable in pseudo-polynomial
time. Traditional inequalities over the arc formulation,
like Capacity Cuts, are also used. Moreover, a novel
feature is introduced in such kind of
algorithms. Powerful new cuts expressed over a very
large set of variables could be added, without
increasing the complexity of the pricing subproblem or
the size of the LPs that are actually
solved. Computational results on benchmark instances
from the OR-Library show very significant improvements
over previous algorithms. Several open instances could
be solved to optimality."
}
@Inproceedings{UpadrastaC13,
Author = "R. Upadrasta and A. Cohen",
Title = "Sub-Polyhedral Scheduling Using (Unit-)Two-Variable-Per-Inequality
Polyhedra",
Booktitle = "Proceedings of the 40th Annual ACM SIGPLAN-SIGACT Symposium on
Principles of Programming Languages (POPL 2013)",
Year = 2013,
ISBN = "978-1-4503-1832-7",
Address = "Rome, Italy",
Pages = "483--496",
Publisher = "ACM Press, New York, USA",
Note = "Also published in SIGPLAN Notices, Volume 48, Number 1",
Abstract = "Polyhedral compilation has been successful in the design
and implementation of complex loop nest optimizers and
parallelizing compilers. The algorithmic complexity and
scalability limitations remain one important weakness. We
address it using sub-polyhedral under-aproximations of
the systems of constraints resulting from affine
scheduling problems. We propose a sub-polyhedral
scheduling technique using
(Unit-)Two-Variable-Per-Inequality or (U)TVPI
Polyhedra. This technique relies on simple polynomial
time algorithms to under-approximate a general polyhedron
into (U)TVPI polyhedra. We modify the state-of-the-art
PLuTo compiler using our scheduling technique, and show
that for a majority of the Polybench (2.0) kernels, the
above under-approximations yield polyhedra that are
non-empty. Solving the under-approximated system leads to
asymptotic gains in complexity, and shows practically
significant improvements when compared to a traditional
LP solver. We also verify that code generated by our
sub-polyhedral parallelization prototype matches the
performance of PLuTo-optimized code when the
under-approximation preserves feasibility."
}
@Inproceedings{vanHeeOSV06,
Author = "K. {van Hee} and O. Oanea and N. Sidorova and M. Voorhoeve",
Title = "Verifying Generalized Soundness for Workflow Nets",
Booktitle = "Perspectives of System Informatics: Proceedings of the
6th International Andrei Ershov Memorial Conference",
Address = "Akademgorodok, Novosibirsk, Russia",
Editor = "I. Virbitskaite and A. Voronkov",
Publisher = "Springer-Verlag, Berlin",
Series = "Lecture Notes in Computer Science",
Volume = 4378,
Pages = "231--244",
Year = 2006,
Abstract = "We improve the decision procedure from [K. van Hee,
N. Sidorova, and M. Voorhoeve. Generalized soundness of
workflow nets is decidable. In Proc. of ICATPN'2004,
volume 3099 of LNCS, pages 197--216, 2004] for the
problem of generalized soundness for workflow nets:
``Every marking reachable from an initial marking with
$k$ tokens on the initial place terminates properly,
i.e. it can reach a marking with $k$ tokens on the final
place, for an arbitrary natural number $k$''. Moreover,
our new decision procedure returns a counterexample in
case the workflow net is not generalized sound. We also
report on experimental results obtained with the
prototype we made and explain how the procedure can be
used for the compositional verification of large
workflows."
}
@PhdThesis{Vasconcelos08th,
Author = "P. B. Vasconcelos",
Title = "Space Cost Analysis Using Sized Types",
School = "School of Computer Science, University of St Andrews",
Address = "St Andrews, UK",
Month = aug,
Year = 2008,
Abstract = "Programming resource-sensitive systems, such as
real-time embedded systems, requires guaranteeing both
the functional correctness of computations and also that
time and space usage fit within constraints imposed
by hardware limits or the environment. Functional
programming languages have proved very good at
meeting the former logical kind of guarantees but
not the latter resource guarantees.
This thesis contributes to demonstrate the applicability
of functional programming in resource-sensitive
systems with an automatic program analysis for
obtaining guaranteed upper bounds on dynamic space
usage of functional programs.
Our analysis is developed for a core subset of
\emph{Hume}, a domain-specific functional language
targeting resource-sensitive systems (Hammond et
al. 2007), and presented as a type and effeect
system that builds on previous sized type systems
(Hughes et al. 1996, Chin and Khoo 2001) and effeect
systems for costs (Dornic et al. 1992, Reistad and
Gifford 1994, Hughes and Pareto 1999). It extends
previous approaches by using abstract interpretation
techniques to \emph{automatically} infer linear
approximations of the sizes of recursive data types
and the stack and heap costs of recursive functions.
The correctness of the analysis is formally proved with
respect to an operational semantics for the language
and an inferrence algorithm that automatically
reconstructs size and cost bounds is presented.
A prototype implementation of the analysis and
operational semantics has been constructed and used
to experimentally assess the quality of the cost
bounds with some examples, including implementations
of textbook functional programming algorithms and
simplified embedded systems."
}
@Inproceedings{Verdoolaege10,
Author = "S. Verdoolaege",
Title = "An Integer Set Library for the Polyhedral Model",
Booktitle = "Proceedings of the 3rd International Congress
on Mathematical Software (ICMS 2010)",
Address = "Kobe, Japan",
Series = "Lecture Notes in Computer Science",
Editor = "K. Fukuda and J. Hoeven and M. Joswig and N. Takayama",
Publisher = "Springer-Verlag, Berlin",
ISBN = "978-3-642-15581-9",
Pages = "299--302",
Volume = 6327,
ISBN = "978-3-642-15581-9",
Year = 2010,
Abstract = "In compiler research, polytopes and related mathematical
objects have been successfully used for several decades
to represent and manipulate computer programs in an
approach that has become known as the polyhedral
model. The key insight is that the kernels of many
compute-intensive applications are composed of loops
with bounds that are affine combinations of symbolic
constants and outer loop iterators. The iterations of a
loop nest can then be represented as the integer points
in a (parametric) polytope and manipulated as a whole,
rather than as individual iterations. A similar
reasoning holds for the elements of an array and for
mappings between loop iterations and array elements."
}
@Incollection{Vigna07,
Author = "G. Vigna",
Editor = "M. Christodorescu and S. Jha and D. Maughan
and D. Song and C. Wang",
Booktitle = "Malware Detection",
Title = "Static Disassembly and Code Analysis",
Publisher = "Springer-Verlag, Berlin",
Year = 2007,
Series = "Advances in Information Security",
Volume = 27,
ISBN = "0-387-32720-4",
Abstract = "The classification of an unknown binary program as
malicious or benign requires two steps. In the first
step, the stream of bytes that constitutes the program
has to be transformed (or disassembled) into the
corresponding sequence of machine instructions. In the
second step, based on this machine code representation,
static or dynamic code analysis techniques can be
applied to determine the properties and function of the
program. Both the disassembly and code analysis steps
can be foiled by techniques that obfuscate the binary
representation of a program. Thus, robust techniques are
required that deliver reliable results under such
adverse circumstances. In this chapter, we introduce a
disassemble technique that can deal with obfuscated
binaries. Also, we introduce a static code analysis
approach that can identify high-level semantic
properties of code that are difficult to conceal."
}
@Inproceedings{YangWGI06,
Author = "Z. Yang and C. Wang and A. Gupta and F. Ivan\v{c}i\'{c}",
Title = "Mixed Symbolic Representations for Model Checking
Software Programs",
Booktitle = "Proceedings of the 4th ACM {\&} IEEE International Conference
on Formal Methods and Models for Co-Design (MEMOCODE 2006)",
Address = "Embassy Suites, Napa, California, USA",
Pages = "17--26",
Publisher = "IEEE Press",
Year = 2006,
ISBN = "1-4244-0421-5",
Abstract = "We present an efficient symbolic search algorithm for
software model checking. The algorithm combines multiple
symbolic representations to efficiently represent the
transition relation and reachable states and uses a
combination of decision procedures for Boolean and
integer representations. Our main contributions include:
(1) mixed symbolic representations to model C programs
with rich data types and complex expressions; and (2)
new symbolic search strategies and optimization
techniques specific to sequential programs that can
significantly improve the scalability of model checking
algorithms. Our controlled experiments on real-world
software programs show that the new symbolic search
algorithm can achieve several orders-of-magnitude
improvements over existing methods. The proposed
techniques are extremely competitive in handling
sequential models of non-trivial sizes, and also compare
favorably to popular Boolean-level model checking
algorithms based on BDDs and SAT.",
}
@Article{YangWGI09,
Author = "Z. Yang and C. Wang and A. Gupta and F. Ivan\v{c}i\'{c}",
Title = "Model Checking Sequential Software Programs
Via Mixed Symbolic Analysis",
Journal = "ACM Transactions on Design Automation of Electronic Systems",
Volume = 14,
Number = 1,
Pages = "1--26",
Year = 2009,
ISSN = "1084-4309",
Publisher = "ACM Press",
Address = "New York, NY, USA",
Abstract = "We present an efficient symbolic search algorithm for
software model checking. Our algorithms perform
word-level reasoning by using a combination of decision
procedures in Boolean and integer and real domains, and
use novel symbolic search strategies optimized
specifically for sequential programs to improve
scalability. Experiments on real-world C programs show
that the new symbolic search algorithms can achieve
several orders-of-magnitude improvements over existing
methods based on bit-level (Boolean) reasoning."
}
@Incollection{ZanioliC11,
Author = "M. Zanioli and A. Cortesi",
Title = "Information Leakage Analysis by Abstract Interpretation",
Booktitle = "SOFTSEM 2011: Theory and Practice of Computer Science",
Series = "Lecture Notes in Computer Science",
Editor = "I. Cern{\'a} and T. Gyim{\'o}thy and J. Hromkovic and K. Jefferey
and R. Kr{\'a}lovic and M. Vukolic and S. Wolf",
Publisher = "Springer-Verlag, Berlin",
ISBN = "978-3-642-18380-5",
Pages = "545--557",
Volume = 6543,
Year = 2011,
Abstract = "Protecting the confidentiality of information stored in
a computer system or transmitted over a public network
is a relevant problem in computer security. The
approach of information flow analysis involves
performing a static analysis of the program with the
aim of proving that there will not be leaks of
sensitive information. In this paper we propose a new
domain that combines variable dependency analysis,
based on propositional formulas, and variables' value
analysis, based on polyhedra. The resulting analysis is
strictly more accurate than the state of the art
abstract interpretation based analyses for information
leakage detection. Its modular construction allows to
deal with the tradeoff between efficiency and accuracy
by tuning the granularity of the abstraction and the
complexity of the abstract operators."
}
@Incollection{ZuffereyWH12,
Author = "D. Zufferey and T. Wies and T. A. Henzinger",
Title = "Ideal Abstractions for Well-Structured Transition Systems",
Booktitle = "Proceedings of 13th International Conference on Verification, Model Checking, and Abstract Interpretation, {VMCAI} 2012",
Series = "Lecture Notes in Computer Science",
Editor = "V. Kuncak and A. Rybalchenko",
Publisher = "Springer-Verlag, Berlin",
ISBN = "978-3-642-27939-3 (Print) 978-3-642-27940-9 (Online)",
Pages = "445--460",
Volume = 7148,
Year = 2012,
Abstract = "Many infinite state systems can be seen as
well-structured transition systems (WSTS), i.e., systems
equipped with a well-quasi-ordering on states that is
also a simulation relation. WSTS are an attractive
target for formal analysis because there exist generic
algorithms that decide interesting verification problems
for this class. Among the most popular algorithms are
acceleration-based forward analyses for computing the
covering set. Termination of these algorithms can only
be guaranteed for flattable WSTS. Yet, many WSTS of
practical interest are not flattable and the question
whether any given WSTS is flattable is itself
undecidable. We therefore propose an analysis that
computes the covering set and captures the essence of
acceleration-based algorithms, but sacrifices precision
for guaranteed termination. Our analysis is an abstract
interpretation whose abstract domain builds on the ideal
completion of the well-quasi-ordered state space, and a
widening operator that mimics acceleration and controls
the loss of precision of the analysis. We present
instances of our framework for various classes of
WSTS. Our experience with a prototype implementation
indicates that, despite the inherent precision loss, our
analysis often computes the precise covering set of the
analyzed system."
}
==============================================================================
<h2>ODC Attribution License (ODC-By)</h2>
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------
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remaining provision of this License shall be valid and enforced to the
fullest extent permitted by law.
10.2 This License is the entire agreement between the parties with
respect to the rights granted here over the Database. It replaces any
earlier understandings, agreements or representations with respect to
the Database.
10.3 If You are in breach of the terms of this License, You will not be
entitled to rely on the terms of this License or to complain of any
breach by the Licensor.
10.4 Choice of law. This License takes effect in and will be governed by
the laws of the relevant jurisdiction in which the License terms are
sought to be enforced. If the standard suite of rights granted under
applicable copyright law and Database Rights in the relevant
jurisdiction includes additional rights not granted under this License,
these additional rights are granted in this License in order to meet the
terms of this License.
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