Because query execution is the most crucial part of Induc- tive logic programming (ILP) algorithms, a lot of effort is invested in developing faster execution mechanisms. These execution mechanisms typically have a lo...
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Because query execution is the most crucial part of Induc- tive logic programming (ILP) algorithms, a lot of effort is invested in developing faster execution mechanisms. These execution mechanisms typically have a low-level implementation, making them hard to debug. Moreover, other factors such as the complexity of the problems handled by ILP algorithms and size of the code base of ILP data mining systems make debugging at this level a very difficult job. In this work, we present the trace-based debugging approach currently used in the development of new execution mechanisms in hipP, the engine underlying the ACE Data Mining system. This debugger uses the delta debugging algorithm to automatically reduce the total time needed to expose bugs in ILP execution, thus making manual debugging step much lighter.
Compatible Observability Don't Cares (CODCs) are a powerful means to express the flexibility present at a node in a multi-level logic network. Despite their elegance, the applicability of CODCs has been hampered b...
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ISBN:
(纸本)1511838288
Compatible Observability Don't Cares (CODCs) are a powerful means to express the flexibility present at a node in a multi-level logic network. Despite their elegance, the applicability of CODCs has been hampered by their computational complexity. The CODC computation for a network involves several image computations, which require the construction of global BDDs of the circuit nodes. The size of BDDs of circuit nodes is unpredictable, and as a result, the CODC computation is not robust. In practice, CODCs cannot be computed for large circuits due to this limitation. In this paper, we present an algorithm to compute approximate CODCs (ACODCs). This algorithm allows us to compute compatible don't cares for significantly larger designs. Our ACODC algorithm is scalable in the sense that the user may trade off time and memory against the accuracy of the ACODCs computed. The ACODC is computed by considering a subnetwork rooted at the node of interest, up to a certain topological depth, and performing its don't care computation. We prove that the ACODC is an approximation of its CODC. We have proved the soundness of the approach, and performed extensive experiments to explore the trade-off between memory utilization, speed and accuracy. We show that even for small topological depths, the ACODC computation gives very good results. Our experiments demonstrate that our algorithm can compute ACODCs for circuits whose CODC computation has not been demonstrated to date. Also, for a set of benchmark circuits whose CODC computation yields an average 28% reduction in literals after optimization, our ACODC computation yields an average 22% literal reduction. Our algorithm has runtimes which are about 25× and memory utilization which is 33× better that of the CODC computation of SIS.
Innermost strategies are usually used in compiling term rewriting systems (TRSs) since they allow to efficiently build result terms in a bottom-up fashion. However, innermost strategies do not always give the shortest...
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This paper presents an approach based on a Horn fragment of Concurrent Transaction logic (CTR) for semantic description and execution of programming languages. The Horn notation is used in much the same way that plain...
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This paper presents an approach based on a Horn fragment of Concurrent Transaction logic (CTR) for semantic description and execution of programming languages. The Horn notation is used in much the same way that plain Horn logic is used to specify semantics of programming languages. However, CTR extends that framework a deductive database language which provides a declarative, logic programming framework that naturally accommodates the notions of store, store updates, dataflow in declarative languages, data-driven concurrency, and message passing concurrency. The contributions of this paper are twofold: it shows how the semantics of concurrent programming languages can be fully specified in a Horn-based logic framework;and it demonstrates that CTR-based logical denotations provide a unified formal semantics for such languages, which can also serve as a prototyping tool for the language developer.
The PARMC system performs modelc hecking for systems described in the XL language, a variant of CCS. Extending previous work by Dong and Ramakrishnan that compiled XL specifications into an optimized transition relati...
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Current change management solutions apply versionized interfaces to ensure coherent evolution in service environments. This leads to several drawbacks such as an increasing number of service versions and time-consumin...
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This paper is focused on a double extension of traditional logic programming which enhances it following two different approaches. On one hand, extending Horn logic to hereditary Harrop formulas (HH), in order to impr...
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ISBN:
(纸本)1581138199
This paper is focused on a double extension of traditional logic programming which enhances it following two different approaches. On one hand, extending Horn logic to hereditary Harrop formulas (HH), in order to improve the expressive power;on the other, incorporating constraints, in order to increase the efficiency. For this combination, called HH(C), an operational semantics exists, but no declarative semantic for it has been defined so far. One of the main features of (Constraint) logic programming is that the algorithmic behavior of (constraint) logic programs and its mathematical interpretations agree with each other, in the sense that the declarative meaning of a program can be interpreted operationally as a goal-oriented search for solutions. Both operational (algorithmic) and declarative (mathematical) semantics for programs are useful and widely developed in the frame of logic programming as well as in its extension, Constraint logic programming. For these reasons, HH(C) was in need of a more mathematical interpretation of programs. In this paper some fixed point semantics for HH(C) are presented. Taking as a starting point the techniques used by Miller to interpret the fragment of HH that incorporates intuitionistic implication in goals, we have formulated two novel extensions capable of dealing with the whole HH logic, including universal quantifiers, as well as with the presence of constraints. Those semantics are proved to be sound and complete w.r.t. the operational semantics of HH(C).
We present a program logic, Lc, which modularly reasons about unstructured control flow in machine-language programs. Unlike previous program logics, the basic reasoning units in Lc are multiple-entry and multiple-exi...
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作者：
Wotawa, Franz
Institute of Software Technology Inffeldgasse 16b/2 GrazA-8010 Austria
Allocating tasks to computing nodes in a network is an important configuration problem. In the case of fail-safe networks, such configuration must be changed during operation if a computing node fails. Hence, a fast c...
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We propose a generalisation of trace refinement for the verification of inter-procedural programs. Our method is a top-down modular, summary-based approach, and analyses inter-procedural programs by building function ...
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ISBN:
(纸本)9783939897774
We propose a generalisation of trace refinement for the verification of inter-procedural programs. Our method is a top-down modular, summary-based approach, and analyses inter-procedural programs by building function summaries on-demand and improving the summaries each time a function is analysed. Our method is sound, and complete relative to the existence of a modular Hoare proof for a non-recursive program. We have implemented a prototype analyser that demonstrates the main features of our approach and yields promising results.
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