Evolving Legacy Software with a Generic Program

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Evolving Legacy Software with a Generic Program EVOLVING LEGACY SOFTWARE WITH A GENERIC PROGRAM TRANSFORMATION FRAMEWORK USING META-PROGRAMMING AND DOMAIN-SPECIFIC LANGUAGES by SONGQING YUE JEFF GRAY, COMMITTEE CHAIR JEFFREY CARVER XIAOYAN HONG PETER PIRKELBAUER SUSAN VRBSKY A DISSERTATION Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Computer Science in the Graduate School of The University of Alabama TUSCALOOSA, ALABAMA 2015 Copyright Songqing Yue 2015 ALL RIGHTS RESERVED ABSTRACT Advances in the software industry over the past half-century have resulted in a large amount of legacy code implemented across hundreds of different programming languages and paradigms running throughout various application areas. Legacy software requires continuous and rigorous adaptation or modernization in order to avoid progressive decay in quality over time. Modern approaches addressing the needs of modularity and reusability in software engineering have been investigated as effective techniques to assist in software development and maintenance by automating the process of code evolution. The research in this dissertation is focused on applying techniques in software engineering and programming language design to address challenges in software maintenance and evolution. A specific focus area of application is software in the area of High Performance Computing (HPC) with Fortran and C. The research makes a contribution by bringing the power of meta-programming, through Meta-Object Protocols (MOPs), to languages that are widely utilized for solving various problems in HPC. With MOP facilities provided by OpenFortran and OpenC (the two MOPs we built for Fortran and C), developers can build tools to perform arbitrary source-to-source program transformations for legacy software. To simplify the use of MOPs and to reduce the accidental complexities typically associated with the intensive meta-programming paradigm, a textual Domain-Specific Language (DSL) is introduced in our approach, which provides a higher-level abstraction for specifying program transformations, and thus enables direct expression of manipulating program entities. ii There is a general lack of infrastructure support for language extension in terms of building a MOP for an arbitrary language. In order for our approach to accommodate additional programming languages, an extensible framework has been developed in this dissertation work. The framework is composed of a language-independent MOP prototype, called OpenFoo, and a generic front-end DSL (i.e., SPOT). With the assistance of a set of models that describe the aspects and concerns associated with MOP implementation and code modification, the MOP prototype can be extended to create a MOP instance for a specific general-purpose programming language (GPL); and, similarly, the DSL can be extended to accommodate a newly created backend MOP. iii DEDICATION This work is dedicated to Jesus Christ for your grace and unconditional love, to my father and my mother for your support and blessings, to my younger brother for your company in the last two years at UA, and to all my brothers and sisters in Jesus Christ and my dear friends for standing by me throughout the time taken to complete this dissertation. iv LIST OF ABBREVIATIONS AND SYMBOLS ANTLR Another tool for Language Recognition AOP Aspect-Oriented Programming API Application Programming Interface AST Abstract Syntax Tree CASE Computer-Aided Software Engineering CG Conjugate Gradient CLOS Common Lisp Object System CUDA Compute Unified Device Architecture DSL Domain-Specific Languages DMS Design Maintenance System EBNF Extended Backus-Naur Form EDG Edison Design Group EP Embarrassingly Parallel FFT Fast Fourier Transform GPL General-purpose Programming Language HPC High Performance Computing HPF High-Performance Fortran IDE Integrated Development Environment IR Intermediate Representation LOC Lines of Code v MDE Model-Driven Engineering MOP Meta-Object Protocol MPI Message Passing Interface NAS NASA Advanced Supercomputing NPB NAS Parallel Benchmark OFP Open Fortran Parser OOP Object-Oriented Programming OpenMP Open Multiprocessing PTE Program Transformation Engine RSL Rule Specification Language SMP Symmetric Multiprocessing System SPOT Specifying Programming Transformation TXL Turing eXtender Language UML Unified Modeling Language XML Extensible Markup Language vi ACKNOWLEDGMENTS I am pleased to have this opportunity to thank the many colleagues, friends, and faculty members who have helped me during the whole period of my graduate study. First and foremost, I would like to show my gratitude and appreciation to my advisor, Dr. Jeff Gray, for providing me the opportunity to complete my Ph.D. study at the University of Alabama. Without Dr. Gray’s continuous support and encouragement, this work is impossible. When I went through a difficult time in 2010, it was Dr. Gray who lent his helping hand by agreeing to work with me. In the past five years, Dr. Gray has offered me great help and advice toward my research directions, revising the publications, and refining the quality of my research results. I have learned a lot from his outstanding example on how to become a responsible professor and a professional computer researcher. I would also like to extend my gratitude to the other members of my committee. To Dr. Jeffrey Carver, Dr. Xiaoyan Hong, Dr. Peter Pirkelbauer, and Dr. Susan Vrbsky, I feel grateful for your efforts to help me develop the necessary knowledge and skills throughout the stages of my graduate study. I really appreciate your precious time and effort in serving on my committee. To my fellow coworkers at UA, Ke Meng, Bo Fu, Xiannuan Liang, Jing Liu, Jingcheng Gao, Miao Peng, Yan Liang, Yanping Zhang, Zhifeng Xiao, Yu Sun, Hyun Cho, Lei Zeng, Amber Wagner, Ferosh, Jacob, Jonathan Corley, and Songhui Yue, I really appreciate your friendship and all the wonderful and fun times we shared. To all my colleagues in the graduate school at UA, Ashirul Mubin, Dr. John Schmitt, Eric Harris, John Chambers, Kathleen Nodine, Debbie Eads, Sheryl Tubbs, Rebekah Hughes-Brown, vii Mary Williams, and Beth Yarbrough, I really enjoyed working with you as a team to provide professional service to graduate students. I will always be grateful to the financial support from the graduate school. This dissertation would not have been possible without the support of my friends and my family who never stopped encouraging me to persist. Finally, I thank all who have ever helped me on my road towards the completion of my Ph.D. study. viii CONTENTS ABSTRACT ................................................................................................ ii DEDICATION ........................................................................................... iv LIST OF ABBREVIATIONS AND SYMBOLS ........................................v ACKNOWLEDGMENTS ........................................................................ vii LIST OF TABLES ................................................................................... xiii LIST OF FIGURES ................................................................................. xiv 1. INTRODUCTION ...................................................................................1 1.1 Software Maintenance Challenges in High Performance Computing .....................................................2 1.2 Program Transformation Techniques ........................................5 1.2.1 Meta-Programming and Meta-Object Protocol ..........7 1.3 Domain-Specific Languages ......................................................9 1.4 Research Objectives and Contributions ...................................10 1.4.1 Research Questions ...................................................11 1.5 Dissertation Overview .............................................................17 2. BACKGROUND ...................................................................................19 2.1 High Performance Computing .................................................19 2.2 Meta-Programming ..................................................................22 2.2.1 Open Implementation ................................................23 2.2.2 Computational Reflection .........................................24 ix 2.2.3 Meta-Object Protocol ................................................29 2.3 Program Transformation Approaches ......................................31 2.4 Related Work ...........................................................................35 2.4.1 Existing MOPs ..........................................................35 2.4.2 Aspect-Oriented Programming .................................45 2.4.3 Domain-Specific Languages .....................................47 3. EXTENDING PROGRAMS WITH META-PROGRAMMING ..........49 3.1 OpenFortran: A MOP for Extending Fortran Programs ..........50 3.1.1 OpenFortran Design Architecture .............................51 3.1.2 OpenFortran Implementation Details .......................54 3.2 OpenC: A MOP for Extending C Programs ............................59 3.2.1 Benefits of OpenC MOP ...........................................60 3.2.2 OpenC Design and Implementation ..........................62 3.2.3 Implementing a Library in OpenC ............................64 3.3 Case Study: Timer Implementation in NAS ............................68 3.4 Summary ..................................................................................71 3.4.1 Lessons Learned ........................................................72
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