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和灵活的软件开发/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、行为和数据结构的多边图形化描述方案。在该环境中，一个框图一样的图形描述表示功能块之间的数据依赖关系直接转换成可执行的数据驱动程序，保持目标系统的处理结构。包含用于转换的附加基本信息的行为和数据结构也由图表形式表示。例如扩充的序列图，数据结构图，2.一种扩充的动态数据驱动的处理模型，结合了历史敏感的过程和令牌流，被证明是最有前途的原则，在该原则下，从图形规范直接生成的抽象程序以高度并行的方式被解释，而没有任何侧边。3.采用面向数据的通用实现方式，在工程工作站上实现了一个原型系统。在原型系统中，可执行程序的单芯片数据驱动处理器是直接产生的图形规格在一个交互式的environment. Practicable所提出的系统是通过评估规范的过程中的几个实时应用程序，如电梯控制系统和MUSE信号解码器。

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.