A Transportable Programming Language (TPL) System. I. overview

A Transportable Programming Language, TPL, is defined as one that can be used to codeany program that will compile and correctly execute onany machine in a designated range. The range specifies only the minimum software and hardware needed to support the TPL. A HLL-TPL System is one that, in addition to supporting the TPL, can be used to transport any program coded in a dialect of the High-Level Language, HLL, so that it will compile and correctly execute on any machine in a designated range.Methods of implementing a HLL-TPL System are reviewed and it is demonstrated that theSuperset Method, in which the Hypothetical Parent of the HLL (HPHLL) acts as the intermediate language between the dialects of a HLL, leads to a fully transportable High-Level Language—the HPHLL—whose only parameters are: The amount of memory available; and the maximum module size exclusive of arrays. The ongoing work to realize a production version of the FORTRAN-TPL system is described. Its essential characteristic is a fully transportable bifunctional FORTRAN-TPL compiler that converts a dialect of FORTRAN to the intermediate language, HPFORTRAN, and visa-versa.     

基于GCC的VLIW编译系统研究

VLIW机器在单个机器周期中同时发射并执行多个的并行操作,从而获得较高的指令级并行度,这些操作之间的依赖分析和调度工作则被完全交给相应的编译器执行,因此VLIW的并行性能能否充分发挥取决于VLIW体系结构相关编译器的质量。GNU开发的GCC是被最广泛使用的编译系统之一,它具有多语言、多平台支持的能力和开放的结构,能够运用各种成熟的常规编译优化技术生成高效的代码。文章分析了VLIW及GCC的结构特点,提出了一种基于GCC的VLIW编译系统设计方案,利用GCC进行RTL中间代码一级的体系结构无关优化和少量体系结构相关优化,在汇编代码一级针对VLIW结构进行体系结构相关的优化,从而充分利用GCC的成熟编译技术快速开发高效的VLIW多语言编译系统。     

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。     

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 portability of the BCPL compiler

Methods of achieving program portability are discussed, with particular reference to the mobility of compilers. The method of transferring the BCPL compiler is then described including the specification of OCODE which is the language used as an interface between the machine independent and machine dependent parts of the compiler.     

An algol-like assembly language for a small computer

In a classic paper¹ Wirth describes a language which combines the readability of ALGOL 60 with the flexibility and degree of control of a conventional assembly language. This paper gives an outline of a similar language for a small 16-bit computer—the Honeywell DDP-516. Implementing the compiler in its own language by recoding an ALGOL version of the compiler has shown that the language is suitable for large systems. With the compiler written in a high-level language, many enhancements have been possible even though these were not envisaged in the original coding This use of the language clearly demonstrated that a high-level assembly language can be a very effective tool for a small machine as well as for computers like the 360 series.     

A portable lisp compiler

The programming language LISP is usually implemented via an interpreter, and a compiler is added later as a LISP program. However, all such production compilers known to the authors produce explicit instructions for the given computer being used. This paper describes the development of a portable LISP compiler in the sense that only Standard LISP functions are used in its definition and the output is a sequence of abstract machine codes, easily mapped to instruction sequences on current computers. The resulting code is quite efficient, demonstrating once again the maxim that most compiler optimization is largely machine independent.     

Accurate garbage collection in uncooperative environments revisited

Implementing a concurrent programming language such as Java by means of a translator to an existing language is attractive as it provides portability over all platforms supported by the host language and reduces development time—as many low‐level tasks can be delegated to the host compiler. The C and C++ programming languages are popular choices for many language implementations due to the availability of efficient compilers on a wide range of platforms. For garbage‐collected languages, however, they are not a perfect match as no support is provided for accurately discovering pointers to heap‐allocated data on thread stacks. We evaluate several previously published techniques and propose a new mechanism, lazy pointer stacks, for performing accurate garbage collection in such uncooperative environments. We implemented the new technique in the Ovm Java virtual machine with our own Java‐to‐C/C++ compiler using GCC as a back‐end compiler. Our extensive experimental results confirm that lazy pointer stacks outperform existing approaches: we provide a speedup of 4.5% over Henderson's accurate collector with a 17% increase in code size. Accurate collection is essential in the context of real‐time systems, we thus validate our approach with the implementation of a real‐time concurrent garbage collection algorithm. Copyright © 2009 John Wiley & Sons, Ltd.     

面向对象语言编译器的自动测试平台

提出了一种新的面向对象语言编译器自动测试的方法和过程,并在此基础上设计开发了面向对象编译器自动测试工具(O_OCTT)。测试用例的自动生成是编译器自动测试工具的核心,介绍了C 编译器测试用例自动生成的手段和方法,阐述了。O_OCTT设计与实现过程中的关键技术。     

Code compaction for parallel architectures

There are two principal methods used to exploit the parallelism available on a parallel machine: the program to be executed can be optimized by hand, or the program can be automatically converted to parallel machine code by a compiler. The first method usually derives parallelism at the procedure level; a parallel program is written in a high-level language and typically has various modules executing in parallel. By contrast, the compiler methodically transforms the program into parallel code using various transformations, such as code movement. The automatic conversion of a program to parallel code is called compaction or parallelization. This paper describes the evolution of a new compaction program and presents a new algorithm for determining legal code movements. A simulator of the target architecture was used to estimate the execution times of a sample suite of programs before and after compaction. The results verify that substantial advantages arise from applying this compaction technique.     

Jikes RVM动态编译技术分析与性能评测

随着Java语言的广泛应用,Java虚拟机的性能越来越受到人们重视,而虚拟机的动态编译技术是影响其性能的重要因素.Jikes RVM使用Java语言实现了一个Java虚拟机.首先分析了Jikes RVM的3个主要动态编译器的结构及其涉及的关键编译技术,包括基线编译、优化编译和自适应编译,然后利用SPECjvm Client98对Jikes RVM和Sun JVM的动态编译性能进行了测试和比较.测试结果显示,Jikes RVM的性能和Sun JVM性能基本相同,最后针对Jikes RVM的不足提出了改进Jikes RVM 编译器的方法.     

An assessment of modula

Wirth has recently published a new programming language called Modula which he suggests is suitable for the programming of process control systems, computerized laboratory equipment and input/output device drivers. The authors have written a compiler for Modula running on a PDP-11 and generating object code for the same machine. Their experience in writing device drivers for a number of PDP-11 devices is reported, including simple mains frequency clocks, disks, CAMAC and a graphics processor. Some difficulties arose during the writing of these programs; these are investigated and solutions proposed, either within the existing language or by minor modifications to the language. The study shows the extent to which Modula meets the requirements for a general purpose real-time systems-implementations programming language; areas of deficiency are noted.     

GCC后端中四路双精度短向量寄存器的实现

设计和实现一个新的产品化的编译器通常需要几年时间。基于已有的编译器进行修改和扩展,是研发面向新体系结构的编译器的主要途径。GNU编译器集合(GCC)支持多种高级语言和多种目标处理器平台、文档及源代码开放等。基于GCC的Sparc后端,实现了支持四路双精度SIMD指令的四路双精度短向量寄存器的描述。在此过程中,定义了新的目标机,扩充了一类向量模式,定义了一类新的寄存器约束,实现了四路双精度寄存器的描述,定义了四路双精度SIMD指令的机器描述。对于面向此类SIMD指令的内嵌函数,GCC编译器能够正确使用该类向量寄存器来生成对应的SIMD指令。     

一种类型化低级语言的设计与应用

介绍了以构造一个具有更小的需信任计算基础的Java虚拟机系统为目的的研究工作，将一种类型安全的低级语言TLL应用到Java虚拟机的即时编译器中．TLL的类型系统基于多态的类型化入演算，它具有丰富的表现力且能够编码各种高级语言的抽象．基于TLL的一个虚拟机原型系统已经实现，它可以作为实现一个具有微小的需信任计算基础的Java虚拟机的起点．