Extended Static Checking by Calculation Using the Pointfree Transform
نویسنده
چکیده
The pointfree transform offers to the predicate calculus what the Laplace transform offers to the differential/integral calculus: the possibility of changing the underlying mathematical space so as to enable agile algebraic calculation. This paper addresses the foundations of the transform and its application to a calculational approach to extended static checking (ESC) in the context of abstract modeling. In particular, a calculus is given whose rules help in breaking the complexity of the proof obligations involved in static checking arguments. The close connection between such calculus and that of weakest pre-conditions makes it possible to use the latter in ESC proof obligation discharge, where pointfree notation is again used, this time to calculate with invariant properties to be maintained. A connection with the “everything is a relation” lemma of Alloy is established, showing how close to each other the pointfree and Alloy notations are. The main advantage of this connection is that of complementing pen-and-paper pointfree calculations with model checking support wherever validating sizable abstract models.
منابع مشابه
A New Method for Multisensor Data Fusion Based on Wavelet Transform in a Chemical Plant
This paper presents a new multi-sensor data fusion method based on the combination of wavelet transform (WT) and extended Kalman filter (EKF). Input data are first filtered by a wavelet transform via Daubechies wavelet “db4” functions and the filtered data are then fused based on variance weights in terms of minimum mean square error. The fused data are finally treated by extended Kalman filter...
متن کاملExtended Real Functions in Pointfree Topology
In pointfree topology, a continuous real function on a frame L is a map L(R) → L from the frame of reals into L. The discussion of continuous real functions with possibly infinite values can be easily brought to pointfree topology by replacing the frame L(R) with the frame of extended reals L ( R ) (i.e. the pointfree counterpart of the extended real line R = R ∪ {±∞}). One can even deal with a...
متن کاملTransforming Data by Calculation
This paper addresses the foundations of data-model transformation. A catalog of data mappings is presented which includes abstraction and representation relations and associated constraints. These are justified in an algebraic style via the pointfree-transform, a technique whereby predicates are lifted to binary relation terms (of the algebra of programming) in a two-level style encompassing bo...
متن کاملHypothetical Temporal Reasoning with History Encoding (extended Abstract)
In this paper we integrate a history{encoding based methodology developed by Chomicki for checking dynamic database integrity constraints into a situation-calculus based speciication of database updates as proposed by Reiter. By doing this, we are able to: (1) Answer queries about a whole hypothetical evolution of a database, without having to update the entire database and keep all the informa...
متن کاملSecurity Audit using Extended Static Checking: Is It Cost-effective Yet?
This paper describes our experience of doing variation analysis of known security vulnerabilities in C++ projects including core operating system and browser COM components, using an extended static checker HAVOC-LITE. We describe the extensions made to the tool to be applicable on such large components, along with our experience of using an extended static checker in the large. We argue that t...
متن کامل