This article presents the design principles and efficient implementation techniques for ABCL/R3, an object-oriented concurrent reflective language. One of the most distinguished features of ABCL/R3 is compilation techniques using partial evaluation, which effectively remove interpretation from meta-level programs. The meta-level objects are designed so that they can be partially evaluated in an effective manner. Benchmark programs show that our compilation frameworks make object execution drastically faster than interpreter-based implementations, and achieves performance close to nonreflective compilers.

We introduce a transformation system for concurrent constraint programming (CCP). We define suitable applicability conditions for the transformations which guarantee that the input/output CCP semantics is preserved also when distinguishing deadlocked computations from successful ones and when considering intermediate results of (possibly) non-terminating computations. The system allows us to optimize CCP programs while preserving their intended meaning: In addition to the usual benefits that one has for sequential declarative languages, the transformation of concurrent programs can also lead to the elimination of communication channels and of synchronization points, to the transformation of non-deterministic computations into deterministic ones, and to the crucial saving of computational space. Furthermore, since the transformation system preserves the deadlock behavior of programs, it can be used for proving deadlock freeness of a given program with respect to a class of queries. To this aim it is sometimes sufficient to apply our transformations and to specialize the resulting program with respect to the given queries in such a way that the obtained program is trivially deadlock free.

The aim of this work is the development and application of a partial evaluation procedure for rewriting-based functional logic programs. Functional logic programming languages unite the two main declarative programming paradigms. The rewriting-based computational model extends traditional functional programming languages by incorporating logical features, including logical variables and built-in search, into its framework. This work is the first to address the automatic specialisation of these functional logic programs. In particular, a theoretical framework for the partial evaluation of rewriting-based functional logic programs is defined and its correctness is established. Then, an algorithm is formalised which incorporates the theoretical framework for the procedure in a fully automatic technique. Constraint solving is used to represent additional information about the terms encountered during the transformation in order to improve the efficiency and size of the residual programs. ...

this paper we will substantiate our claims.

Parallel and distributed programs often have hardware/problem specific optimizations for improving quality of the program such as efficiency and robustness. Those optimizations, unfortunately, degrade portability and re-usability as they are intertwined with the original algorithm description. Reflective languages, which provide the application programmer extensible and abstract implementation of the language, can describe such optimizations as extensions to the language. The separation of optimization descriptions gains portability and re-usability of both application programs and optimizations. However, the interpretive execution model of reflective languages imposes a large amount of performance overhead, which sometimes outweighs benefits of optimizations. Previous reflective languages prohibit some of operations being modified via reflection, so as to reduce the amount of interpretation overhead. The imperfection of this approach is that it still leaves a considerable amount of overhead, and it yields less flexible, unclear reflective architecture. This dissertation investigates design and compilation framework of meta-interpreters and meta-objects in an object-oriented concurrent language ABCL/R3. By using partial evaluation to compile reflective programs, ABCL/R3 achieves flexible and lucid reflective architecture and efficient execution at the same time. We design full-fledged meta-interpreters by examining several concurrent programming examples. A newly proposed delegation mechanism enables to define modular and scope controlled extensions to meta-interpreters. We design meta-objects by exploiting the notion of reader/writer methods in a concurrent object-oriented language Schematic, so that they can be effectively partially evaluated. The compilation frameworks of meta-interpreters and meta-objects basically translate concurrent object definitions into a sequential program, then apply partial evaluator for a sequential language, and generates a program in a (non-reflective) concurrent object-oriented language, in which base-level and meta-level objects are collapsed to single level objects. The efficiency of generated programs is demonstrated by several benchmark programs, in which our compiler exhibits performance close to non-reflective languages.

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Computational reflection gives programming languages high flexibility, which is useful for parallel/distributed programming. On the other hand, its interpreter based execution model makes efficient implementation difficult. Especially, meta-objects in concurrent languages are described with explicit state transition, which makes program reasoning---such as partial evaluation---difficult. In this paper, we propose a new meta-object design, which exploits reader/writer methods in our concurrent object-oriented language Schematic. The crux of the design is separation of state-related operations from others, which allows us to optimize meta-objects using an existing partial evaluator because the most methods in the meta-objects can be regarded as a sequential program. 1 Introduction 1.1 Reflection in Parallel/Distributed Programs Practical parallel and distributed programs often have complicated computation and communication structures for achieving efficiency, fault-tolerance, portabili...