5,259 research outputs found
Control dependence for extended finite state machines
Though there has been nearly three decades of work on program slicing, there has been comparatively little work on slicing for state machines. One of the primary challenges that currently presents a barrier to wider application of state machine slicing is the problem of determining control dependence. We survey existing related definitions, introducing a new definition that subsumes one and extends another. We illustrate that by using this new definition our slices respect Weiser slicingās termination behaviour. We prove results that clarify the relationships between our definition and older ones, following this up with examples to motivate the need for these differences
Abstract Program Slicing: an Abstract Interpretation-based approach to Program Slicing
In the present paper we formally define the notion of abstract program
slicing, a general form of program slicing where properties of data are
considered instead of their exact value. This approach is applied to a language
with numeric and reference values, and relies on the notion of abstract
dependencies between program components (statements).
The different forms of (backward) abstract slicing are added to an existing
formal framework where traditional, non-abstract forms of slicing could be
compared. The extended framework allows us to appreciate that abstract slicing
is a generalization of traditional slicing, since traditional slicing (dealing
with syntactic dependencies) is generalized by (semantic) non-abstract forms of
slicing, which are actually equivalent to an abstract form where the identity
abstraction is performed on data.
Sound algorithms for computing abstract dependencies and a systematic
characterization of program slices are provided, which rely on the notion of
agreement between program states
Amorphous slicing of extended finite state machines
Slicing is useful for many Software Engineering applications and has been widely studied for three decades, but there has been comparatively little work on slicing Extended Finite State Machines (EFSMs). This paper introduces a set of dependency based EFSM slicing algorithms and an accompanying tool. We demonstrate that our algorithms are suitable for dependence based slicing. We use our tool to conduct experiments on ten EFSMs, including benchmarks and industrial EFSMs. Ours is the first empirical study of dependence based program slicing for EFSMs. Compared to the only previously published dependence based algorithm, our average slice is smaller 40% of the time and larger only 10% of the time, with an average slice size of 35% for termination insensitive slicing
The Transitivity of Trust Problem in the Interaction of Android Applications
Mobile phones have developed into complex platforms with large numbers of
installed applications and a wide range of sensitive data. Application security
policies limit the permissions of each installed application. As applications
may interact, restricting single applications may create a false sense of
security for the end users while data may still leave the mobile phone through
other applications. Instead, the information flow needs to be policed for the
composite system of applications in a transparent and usable manner. In this
paper, we propose to employ static analysis based on the software architecture
and focused data flow analysis to scalably detect information flows between
components. Specifically, we aim to reveal transitivity of trust problems in
multi-component mobile platforms. We demonstrate the feasibility of our
approach with Android applications, although the generalization of the analysis
to similar composition-based architectures, such as Service-oriented
Architecture, can also be explored in the future
Understanding Program Slices
Program slicing is a useful analysis for aiding different
software engineering activities. In the past decades, various
notions of program slices have been evolved as well as a number
of methods to compute them. By now program slicing has numerous
applications in software maintenance, program comprehension,
reverse engineering, program integration, and software testing.
Usability of program slicing for real world programs depends on
many factors such as precision, speed, and scalability, which
have already been addressed in the literature. However, only a
little attention has been brought to the practical demand: when
the slices are large or difficult to understand, which often
occur in the case of larger programs, how to give an explanation
for the user why a particular element has been included in the
resulting slice. This paper describes a reasoning method about
elements of static program slices
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