A shorthand preprocessor for IDMS COBOL

Aspects of software development using Codasyl COBOL DML are considered. In limited trials, a preprocessor which makes a terse DML syntax available has been found to increase programmer productivity and improve software quality.     

可视编译器的设计与实现

通过一个实际的可视编译器开发实例,描述编译器前端的实现方法。这个编译程序除了易于操作的窗口程序外,还包含了标准C语言子集的编译器。这套编译器涵盖了词法分析器、语法分析器、语义分析器、中间代码生成器和简单错误处理器等一整套程序。通过这个实例可以直观地表现词法和语法的构造过程,图文并茂,生动说明编译器中词法器、语法器的功能及其构造过程。     

A convenient way to incorporate semantic actions in two-pass compiling schemes

We present a simple method for connecting semantic actions to parsers. Although applicable to any kind of parser it is especially suited for LR parsers. The method is based on the idea of separating syntax analysis and semantic processing and executing semantic actions by procedures, similar to those of a recursive descent compiler. The procedures are driven by structural information about the source program, which is collected during parsing. The method is applicable to L-attributed grammars. It can be incorporated easily into any existing parser.     

基于IEC61131-3的IL编译器的设计与实现

为解决目前国内各厂PLC(programmable logic controller)产品的编程语言互不兼容,使得不同系列产品的PLC编译器可重用性很低的问题,设计实现了基于IEC61131-3标准的IL(instruction list)语言编译器.首先设计了编译器的逻辑结构,借助Flex和GNU Bison工具,按照标准IL语言的词法,语法要求,设计并实现了词法、语法分析器,简述了生成目标代码具体实现方法,然后在数控系统中进行了测试运行,实验结果表明,该编译器能正确解释标准IL语言的用户程序,且运行可靠.     

基于可视化程序设计语言的编译系统

采用面向对象技术设计可视化程序设计语言的编译系统，通过对复杂的可视化图片语法进行分析，将各语法现象以语法单元类的形式进行抽象分类，提出了编译器－编译器的设计策略，给出了从可视化图片设计语言到伪指令代码的解决方法。主要研究在面向对象的编辑环境中如何实现满足硬件设备控制器的稳定、高效的编译系统。通过将可视化程序语言分析器(VPLPG)和小型的类C编译(LCC)器配合使用最终实现可视化程序设计语言的编译系统。     

基于边缘轮廓特征的实时车型分类

采用面向对象技术设计可视化程序设计语言的编译系统,通过对复杂的可视化图片语法进行分析,将各语法现象以语法单元类的形式进行抽象分类,提出了编译器-编译器的设计策略,给出了从可视化图片设计语言到伪指令代码的解决方法.主要研究在面向对象的编辑环境中如何实现满足硬件设备控制器的稳定、高效的编译系统.通过将可视化程序语言分析器(VPLPG)和小型的类C编译(LCC)器配合使用最终实现可视化程序设计语言的编译系统.     

Compaction of diagnostic messages for compilers

The use of a space optimal storage scheme for compiler diagnostic messages is described. The space reduction achievable through word coding may be predicted in terms of text length, vocabulary size and average word length. A method of word or phrase selection is discussed. Illustration is made by application to the FORTRAN FTN and COBOL compilers under the operating system KRONOS for the CDC 6400 computer.     

Java中异常结构的语法分析研究

为了提高Java的运行速度,人们对Java编译器进行了深入研究,发现异常结构对编译器的语法分析、语义分析及代码优化都有一定的影响。为了降低异常结构带来的不利影响,文中针对Java中的异常结构提出了一种语法分析方法。该方法采用G树作为语法分析树,较传统的语法分析树的时空效率有明显提高,不仅提高了语法分析的效率,而且提高了语义分析的效率。     

An empirical analysis of COBOL programs

This paper describes results obtained from a static analysis of 340 COBOL programs collected from commercial and industrial installations. The analysis was performed by a syntax analyser designed specifically to analyse source program statements, gather detailed information and produce a report on the definition and use of data and language in the programs analysed.     

Diagnostic messages

An algorithm is presented for the compiler diagnostic phase by the introduction of a dictionary concept with elimination of duplicate words, synonymous words and messages, special symbols and non-uniform spellings. The result is compared with an American Standard COBOL Compiler. This concept can be extended beyond the compilers to all systems which issue extensive messages. It will simplify modularity design and aid in standardization of output format.     

A statistical analysis of syntax errors

A study of errors made by Pascal programmers is described. The results of this study are discussed in relation to compiler syntax error recovery procedures. It is found that syntax errors made in practice are quite simple and occur relatively infrequently (generally at most one per sentence of the language). Also a few types of errors account for most occurrences. These and other findings from the study are helpful in evaluating compiler error handling procedures. A discussion of the relation between these errors and language constructs is presented. Other uses of the information obtained from the study are briefly described.     

语法分析方法研究评述及其应用

语法分析作为编译过程中一个不可缺少的步骤,对其进行研究有着非常重要的意义.阐述了语法分析方法研究的现状,并对之进行了具体的分析和探讨,介绍了语法分析方法的各种应用,对语法分析方法进行了总结和展望.     

UK government venture into standards

Standards in computing have long been talked about but little has happened. Microcomputing is little different and possibly worse. The government is now taking a lead and two computer compiler validation schemes are under development, COBOL at the NCC and Pascal at BSI. This white paper stresses the need for greater involvement and commitment by industry in standards making. The government appears ready to play its part. It is a great opportunity for anyone with a professional interest in computing to start making a real contribution. As good a means as any would be to study in detail this important white paper.     

Use of a formal notation for static semantics in compiler design

Formal notations for the specification of the syntax and the dynamic semantics of languages exist and are of great benefit to the compiler writer. However, formal notations for the static semantics of languages have tended to be tools of the language designer and of little practical significance to the compiler writer. This paper describes how a particular notation was used to assist in the implementation of a Cobol compiler and of an interpreter for a simulation language.     

一个自动编译系统ACS

本文介绍一个自动编译系统ACS。对某上下文无关文法语言,写出其词法描述、语法描述、语义描述和目标机描述。ACS系统可以自动生成此语言在目标机上的编译程序。ACS系统由六个子模块组成:词法自动生成器、语法自动生成器、语义自动生成器、中间语言转换程序、优化程序和代码自动生成器。本文将分别讨论这六个子模块的原理和功能,还将给出用ACS系统生成的一个编译程序实例—Mini_Ada编译程序。     

Testing syntax and semantic coverage of Java language compilers

Software testing is a critical and important stage of the application software development life-cycle. Testing is a verification activity that affects the overall software quality. The verification of critical and dependable computer software such as real-time safety-critical software systems consumes about 50% of the project time. In this work, we consider testing compilers. Since a compiler is a highly usable software, an increased emphasis on reliability requires a careful testing before releasing the compiler. In compiler testing, the compiler implementation is verified to conform to the specified language syntax and semantic available in the standard language documentation. In this work, an algorithm is designed and a tool is developed to automate the generation of test cases to check the language syntax. In addition, we propose a heuristic approach to cover language semantics. Since Java is a relatively new programming language, we concentrate on testing the adherence of new Java compilers to the language syntax and semantics.     

一种简单高级语言编译器的设计

在编译原理和虚拟机技术的基础上,采用一种高级语言设计了一个简单的编译器。通过词法分析、语法分析和中间代码、虚拟机等进程,将源程序编译成目标程序,实现了复杂编译器的简单设计。     

The design of a pascal compiler

The development of a compiler for the programming language PASCAL¹ is described in some detail. Design decisions concerning the layout of program and data, the organization of the compiler including its syntax analyser, and the over-all approach to the project are discussed. The compiler is written in its own language and was implemented for the CDC 6000 computer family. The reader is expected to be familiar with Reference 1.     

基于JavaCC的SQL编译器的设计与实现

采用扩展的巴科斯范式(EBNF)定义SQL语言的语法规则,提出了一种基于分析器自动生成工具(JavaCC)的SQL语言编译器的设计模型。该模型采用Java语言开发,具有良好的平台无关性;分别从词法、语法和语义分析、信息提取等方面进行编译器的设计与实现。实际运行结果表明:该模型能够快速高效地构建SQL编译器,且具有良好的可扩展性。