针对流水冲突的微处理器功能验证程序的自动生成

功能验证是处理器设计中的关键问题，而基于激励向量仿真的方法是功能验证的主流技术，其难点在于如何产生高效的测试程序。研究了针对流水冲突的测试程序的自动生成方法。与常规技术相比，该方法适用于深度流水、指令系统复杂的处理器，具有自动化程度高、针对性强等优点。本文方法已应用于32位RISC处理器的验证中，取得了良好的效果。     

基于程序依赖图的静态BPEL程序切片技术

传统程序切片技术在计算BPEL程序切片时会产生切片不完备问题,为此,提出一种基于程序依赖图的BPEL静态程序切片技术。该技术根据BPEL语言的特点,通过建立BPEL程序依赖图,计算BPEL程序切片。案例分析表明,该技术能够获得更加全面的程序切片,从而可以帮助软件工程人员更好地测试、调试和维护BPEL程序。     

基于线程的Java程序自动并行转换技术

Java程序的并行化研究是一个重要课题.提出一种Java程序的自动并行转换技术,并充分利用Java语言本身提供的多线程机制,通过操作冲突性检测等方法将串行化的Java程序自动转化成并行化程序.使得转化后的并行化程序在多处理机操作系统的支持下,能在共享内存的多处理机系统上运行,从而提高了程序的运行效率.     

非函数依赖程序不变量动态检测技术研究

讨论了程序不变量的内涵,研究并建立了程序不变量动态生成系统的理论模型。在该模型中,针对非函数依赖程序不变量动态生成理论、方法和技术进行了阐述。基于数据库的理论提出了一种新的非函数依赖程序不变量动态检测技术,针对各种常见非函数依赖程序不变量类型建立了一系列检测方法。此不变量检测技术通过数据库中提供的SQL条件查询功能,灵活地检测各种常见类型的非函数依赖程序不变量,并且可以根据用户的实际需要随时指定新的程序不变量查询条件。该方法和Daikon等现有的程序不变量检测工具检测方法比较具有明显的特色和优势：第一,基于关系数据库技术,具有良好的可扩展性;第二,使用SQL条件查询功能实现非函数依赖程序不变量检测,检测方法具有很好的灵活性。     

Post-Failure Reconfiguration of CSP Programs

In this paper a technique called process merging is introduced. This technique allows the merging of two communicating sequential processes into a new single process. Thus, this technique can be used to reconfigure a distributed program after a faulty processing element has been detected. The technique is most applicable to dedicated multiple microprocessor systems where the need for continuous operation is critical. A process merging algorithm which operates on distributed programs using the CSP notation is presented in detail and its operation is discussed. In order to illustrate the merging technique, the algorithm's behavior is demonstrated using two classical distributed programs: the Bounded Buffer, Producer, Consumer program and the Dining Philosophers program. Finally, the merging technique is examined with respect to its demands on overall system operation and overhead. This examinatiQn leads to suggestions for future research.     

过程跟踪器在信息管理系统中的应用

应用程序中存在的大量问题是用户在使用程序中的理解问题。应用程序过程跟踪器是这个问题的一个解决方案。这是一个帮助用户找出问题所在的强有力的工具，并使远程在线技术支持成为可能。使用应用程序过程跟踪器的主要目的是极大减少用户和专业技术人员在寻找问题上所花费的时间和费用。任何事件通过一组由用户设定的配置文件来触发过程跟踪器，并在日志文件里写入一条记录。就是这个由事件查看器来找出问题所在是本文的要点。     

过程跟踪器在信息管理系统中的应用

应用程序中存在的大量问题是用户在使用程序中的理解问题。应用程序过程跟踪器是这个问题的一个解决方案。这是一个帮助用户找出问题所在的强有力的工具,并使远程在线技术支持成为可能。使用应用程序过程跟踪器的主要目的是极大地减少用户和专业技术人员在寻找问题上所花费的时间和费用。任何事件通过一组由用户设定的配置文件来触发过程跟踪器,并在日志文件里写入一条记录。就是这个由事件查看器来找出问题所在是本文的要点。     

An incremental version of iterative data flow analysis

A technique is presented for incrementally updating solutions to both union and intersection data-flow problems in response to program edits and transformations. For generality, the technique is based on the iterative approach to computing data-flow information. The authors show that for both union and intersection problems, some changes can be incrementally incorporated immediately into the data-flow sets while others are handled by a two-phase approach. The first phase updates the data-flow sets to overestimate the effect of the program change, enabling the second phase to incrementally update the affected data-flow sets to reflect the actual program change. An important problem that is addressed is the computation of the data-flow changes that need to be propagated throughout a program, based on different local code changes. The technique is compared to other approaches to incremental data-flow analysis     

Data Flow Analysis as a General Concept for the Transport of Verifiable Program Annotations

Just-in-Time (JIT) compilation is frequently employed in order to speed-up the execution of platform-independent and dynamically extensible mobile code applications. Since the time required for dynamic compilation directly influences a program's execution time, JIT compilers usually utilize only simple and fast techniques for program analysis and optimization. To improve further the analysis and optimization process of such compilers program annotations can be used.However, mostly all current annotation approaches suffer from the fact that the verification of transmitted program information is time consuming and therefore will not be carried out on the consumer side of a mobile code system. In this paper, we present a verifiable annotation technique that is based on a well known iterative data flow algorithm and which can be used for the transmission of all program information that can be derived through data flow analysis. Preliminary measurements of compilation and verification time indicate that the presented technique seems to be implementable and therefore could be used as an all-purpose transportation technique for safe program annotations.     

Employing static information in the generation of test cases

A commonly used approach for detecting defects in a program is to generate a suite of test inputs which exercises the entire program under a given testing criterion. Current techniques to generate test cases automatically that satisfy a testing criterion choose test input data by considering the testing requirements in an arbitrary order. In this paper, a technique is presented that groups the requirements and orders the generation of the test cases to reduce the number of test cases generated. The grouping is based on the statically determined property of post-dominance. Test cases for each group are generated taking into account requirements for other groups. The use of this technique to generate test cases can be expected to produce fewer test cases that have to be retained with the software. A smaller number of test cases will require less effort and resources to test the software. The technique is especially useful in the maintenance environment, whether retesting of a changed program is done exhaustively or incrementally. The technique not only attempts to minimize the number of test cases generated but also reduces the effort to generate the test cases using the concept of a program slice.     

交通事故再现三维仿真技术

该文将OpenGL技术应用于交通这事故再现领域，简述了OpenGL技术的基本原理，基于虚拟现实技术，开发了三维动画程序。可以三维动画的形式车辆在事故过程中的运动，在所构造的虚拟世界中，用户可以根据实际案例的情况，调节演示的基本要素近似实际现场，通过对实际事故案例的演示表明本研究适用于交通事故再现领域。     

Symbolic evaluation with structural recursive symbolic constants

Symbolic evaluation is a technique used for many purposes: program analysis, program verification, program transformation. The paper focusses on a novel approach which allows one to symbolically evaluate programs with respect to predicates denoting subsets of a user-defined data domain. The data domain is assumed to be recursively defined and the predicates can be defined by structural induction on the data. An application of the technique to the textual reduction of recursive programs is sketched.     

一种基于层次切片谱的软件错误定位技术

传统的软件错误定位技术通常利用测试覆盖信息计算程序语句发生错误的可疑度进行软件错误定位,但是这种定位技术没有充分考虑程序本身固有的依赖信息,缺乏语句筛选,从而使错误定位的精度受限.提出了一种基于层次切片谱的错误定位技术,以提高面向对象程序中的错误定位效率.这种技术首先分析程序不同粒度层次元素(包、类、方法以及语句)之间的依赖信息,对可能发生错误的元素进行筛选,缩小错误查找范围;在此基础上,建立了层次切片谱模型,并定义了一种可疑度度量方法;最后根据该可疑度结果从大到小的顺序进行错误定位.通过实验验证了基于层次切片谱的错误定位技术的有效性,且比基于程序谱的Tarantula 技术、Union 技术、Intersection 技术效率更高.     

Program Slicing-Based Regression Testing Techniques

After changes are made to a previously tested program, a goal of regression testing is to perform retesting based on the modifications while maintaining the same testing coverage as completely retesting the program. This paper presents a novel approach to data flow based regression testing that uses slicing algorithms for the explicit detection of definition-use associations that are affected by a program change. An important benefit of this slicing technique is that, unlike previous techniques, neither data flow history nor recomputation of data flow for the entire program is required to detect affected definition-use associations. The program changes drive the recomputation of the required partial data flow through slicing. Another advantage is that the technique achieves the same testing coverage with respect to the affected definition-use associations as a complete retest of the program, without maintaining a test suite. Thus, the overhead of maintaining and updating a test suite is eliminated.     

基于IDA-Pro的软件逆向分析方法

二进制程序转换作为软件逆向分析的主要手段发挥着积极作用。该文给出一种程序转换方法,应用软件二进制程序经IDA Pro反汇编得汇编语言程序,依据下推自动机原理设计汇编文法识别该汇编文件、制定相应的转换规则和优化措施将汇编语言转换成中间语言。转换所得中间语言可读性较强,具有通用性且易于理解。该方法达到了较高的自动化程度,缩小了目标程序的代码量,其应用可有效地减少软件分析和调试人员在追踪代码时所需的时间和工作量。给出应用上述方法进行程序转换的实例。     

设计与实现安全的广播电台自动化播出系统

基于数字音频技术、计算机网络技术和多媒体技术的自动化播出系统改变了广播电台传统的广播节目制作、管理和播出模式，实现节目的制作、播出数字化和自动化。该文阐述了当前广播电台自动化播出系统发展的现状，介绍了数字音频压缩编码技术，从软、硬件技术两个方面对自动化播出系统的安全播出机制进行了有益的探讨和积极地尝试，提出了待播出节目锁定、节目自动预载、播出站数据库多指向技术和网络状态智能判断等技术，设计实现了用于广播电台的一套安全的自动化播出系统，希望藉此对这种新兴的广播技术的系统安全机制进一步完善，从而达到对播出节目内容进行安全管理和播出节目进行安全播出的目的，使节目的录制、编辑和播出数字化、自动化、安全化，并可支持对节目的审听以及提供音频资料在线访问和音频节目数据库的管理。     

Exploiting parallelism across program execution: a unificationtechnique and its analysis

A new technique for source-to-source transformation of sequential programs is described. It is shown that the transformed programs so generated provide significant speedups over the original program on vector processors and vector multiprocessors. The parallelism that arises when multiple instances of a program are executed on simultaneously available data sets is exploited. This is in contrast to the existing approaches that aim at detecting parallelism within a program. The analytic model is used to prove the optimality of the complete first policy for block selection for a class of program graphs known as nonregressive graphs. Analytic and simulation models of the technique clearly indicate the speedups that could be achieved when several data sets are available simultaneously, as is the case in many fields of interest     

Windows的钩子技术及实现

使用钩子技术,应用程序可以监视指定窗口的某种消息.当截获到消息时,应用程序的钩子函数既可以加工处理该消息,也可以继续传递该消息,还可以强制结束消息的传递,因此,应用程序可以实现普通程序难以实现的功能.本文介绍了钩子的基本概念和类型,还介绍了钩子技术实现的方法,并给出了鼠标和键盘系统钩子的应用示例,为工程人员开发和使用钩子提供了一定的技术支持.     

同时多微线程体系结构研究

随着生产工艺的提高,芯片上能集成越来越多的晶体管,多线程技术也逐步成为一种主流的处理器体系结构技术.提出一种融合同时多线程技术和微线程技术的新型体系结构同时多微线程(simultaneous multi-microthreading,SMMT),并给出同时多微线程体系结构的实现方案.SMMT有效结合同时多线程技术硬件代价小和微线程技术能够加速单进程应用的优点,通过软硬件协同的方式充分挖掘单进程程序的微线程级并行性.通过在设计的龙芯2号同时多微线程处理器上进行性能评测,结果表明,同时多微线程体系结构能够有效地加速单进程的程序,以很小的硬件代价显著地提高了处理器的性能.     

用Z形式化描述程序切片

程序切片是一种重要技术,已广泛地应用于软件工程的各个领域,如程序理解、维护、调试、测试、复用、度量等.虽然,越来越多的研究者致力于程序切片工作,然而由于缺少形式化方面的工作导致程序切片可能存在不一致性和模糊性.本文尝试着用Z语言来形式化描述程序切片,考虑了程序切片中诸如程序依赖图和程序切片算法等常用的方面.该形式化描述不仅能帮助人们正确地理解程序切片的含义,而且还能够从比较严格的意义上明确程序切片的应用领域.