A Study on a Direct Transformation System of Natural Specification into Executable Program

该项目的主要目标是建立一个自然而灵活的软件开发/维护环境，在该环境中，应用系统的易于理解的图形化规范直接转换为基于动态数据驱动方案的高度并行的可执行程序。主要研究成果如下：1.建立了系统功能、行为和数据结构的自然表示的多边形图规格说明方案。在该环境中，表示功能块之间的数据依赖关系的图形化描述的框图被直接转换为保持目标系统的处理结构的可执行数据驱动程序。包含用于转换的附加基本信息的行为和数据结构也用图表形式表示。2.结合历史敏感进程和令牌流的扩展动态数据驱动处理模型被证明是最有前景的原则，在该模型下，直接从图规范生成的抽象程序以高度并行的方式被解释，没有任何副作用。3.基于面向数据的方法，通过引入通用实现风格，在工程工作站上构建了一个原型系统。在该原型系统中，可以直接从交互环境中的图形规格说明生成单片数据驱动处理器的可执行程序，并通过对电梯控制系统和缪斯信号解码器等几个实时应用的规格说明流程的评估，验证了该系统的可行性。

The main objective of this project is to establish a natural and flexible software development/maintenance environment in which easily understandable diagrammatic specifications for appli-cation systems are directly transformed into highly-parallel executable programs based upon the dynamic data-driven scheme. The results obtained in the project are summarized as following :1.Multilateral diagrammatic specification scheme was established for natural representation of system function, behavior and data-structures. In the environment, a block diagram like graphical descriptions representing data dependencies among functional blocks are directly transformed into executable data-driven programs preserving the processing structures of target systems. Behavior and data structures which contain additional essential information for transformation are also represented by diagrammatic forms. e.g. augmented sequence charts, data-structure diagrams, state transition diagrams and decision tables.2.An augmented dynamic data-driven processing model incorporating history-sensitive processes and streams of tokens was proved to be the most promising principle under which the abstract pro-grams directly generated from the diagrammatic specifications are interpreted in a highly-parallel fashion without any side-effects.3.A prototype system were built on an engineering workstation by introducing a generic imple-mentation style based on the data oriented approach. In the prototype, executable programs for a single chip data-driven processor are directly generated from the diagrammatic specifications in an interactive environment.Practicability of the proposed system was demonstrated through evaluating specification process for several real-time applications, e.g. a lift control system and a MUSE signal decoder.