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IBM Journal of Research and Development

Issue 6 • Date Nov. 1980

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Displaying Results 1 - 16 of 16
  • Preface

    Page(s): 658 - 659
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (179 KB)  

    Programming languages have been the media for communicating our requirements to computers throughout the history of digital data processing. The basic goals for these languages, and for the processors that produce the corresponding executable programs, have changed surprisingly little over the years View full abstract»

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  • Improved Optimization of FORTRAN Object Programs

    Page(s): 660 - 676
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1310 KB)  

    For many years the FORTRAN H Extended compiler has produced highly optimized object programs for IBM System/360 and System/370 computers. A study of the object programs revealed, however, that important additional optimizations were possible, and the compiler has been enhanced accordingly. First, the range of cases handled by the optimization techniques already present in the compiler has been extended. For example, more duplicate computations are eliminated, and more invariant computations are moved from inner to outer loops. Second, several new optimizations have been added, with subscript computation and register allocation receiving particular attention. Third, certain optimization restrictions have been removed. This paper describes these improvements and reports their effects. View full abstract»

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  • Optimization and Code Generation in a Compiler for Several Machines

    Page(s): 677 - 683
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (488 KB)  

    This paper describes optimization techniques that have been implemented in a compiler which was designed to produce code comparable to that produced by hand. Additional optimization methods were incorporated into successive versions of the compiler. It was found that no single method was effective with all compiled programs but that each of the techniques described was effective for some programs. View full abstract»

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  • Compilation to Compact Code

    Page(s): 684 - 691
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (660 KB)  

    A compilation process is described that emphasizes small object code rather than fast object code. The approach entails synthesizing an instruction set and an interpreter for that instruction set during compilation of an individual source program. Numerical results are given for compiling a systems programming subset of PL/I to System/370 code. View full abstract»

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  • Strength Reduction for Division and Modulo with Application to Accessing a Multilevel Store

    Page(s): 692 - 694
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (267 KB)  

    A method for replacing certain division and modulo operations by additions and subtractions is presented. This optimization allows efficient and easy use of partitioned arrays to access a multilevel store. View full abstract»

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  • The Experimental Compiling System

    Page(s): 695 - 715
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1524 KB)  

    The Experimental Compiling System (ECS) described here represents a new compiler construction methodology that uses a compiler base which can be augmented to create a compiler for any one of a wide class of source languages. The resulting compiler permits the user to select code quality ranging from highly optimized to interpretive. The investigation is concentrating on easy expression and efficient implementation of language semantics; syntax analysis is ignored. View full abstract»

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  • Some Techniques for Compile-Time Analysis of User-Computer Interactions

    Page(s): 716 - 731
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (978 KB)  

    Compile-time techniques for analyzing user-computer interactions and the relationships and dependencies among items of data that exist during the execution of interactive application programs are presented. These techniques are useful in constructing efficient compilers for languages in which such interactions and data item relationships and dependencies are described by nonprocedural statements. The practical value of using nonprocedural descriptions is that they ease the task of the application programmer. View full abstract»

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  • A Business Language

    Page(s): 732 - 746
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1014 KB)  

    The paper describes a language and supporting interactive system for use by the small businessman. To help the businessman-user understand and apply an application program expressed in the language, he can watch the application run in a single-step mode. If tailoring of the application program is necessary, the system guides the user by diagnosing inconsistencies in the modified program. The user controls production processing from the same user interface. In the first part of the paper, the language is described. Next some example user sessions are outlined. Finally the prototype implementation and some design issues are discussed. View full abstract»

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  • A Language for Extended Queueing Network Models

    Page(s): 747 - 755
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (764 KB)  

    Queuing networks are popular as models of performance of computer systems and communication networks. The Research Queueing Package, Version 2 (RESQ2), is a system for constructing and solving extended queuing network models. We refer to the class of RESQ2 networks as “extended” because of characteristics absent from most queuing models. RESQ2 incorporates a high-level language to concisely describe the structure of the model and to specify constraints on the solution. A main feature of the language is the capability to describe models in a hierarchical fashion, allowing an analyst to define parametric submodels which are analogous to macros or procedures in programming languages. RESQ2 thus encourages use of structured models to effectively evaluate complex systems. View full abstract»

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  • Grammar Characterization of Flowgraphs

    Page(s): 756 - 763
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (584 KB)  

    An extension of the scheme grammar concept given by Urschler is formalized. It is also shown that, in the usual hierarchy of the theory of formal languages, the language generated by the scheme grammar is regular (type 3). The last section gives the description of a system for the automatic structuring of programs, which applies these concepts to the Mills algorithm with some modifications. View full abstract»

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  • A Data Definition Facility Based on A Value-Oriented Storage Model

    Page(s): 764 - 782
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1554 KB)  

    A data definition facility is presented that provides a consistent description of both primitive and user data. It is based on a value-oriented storage model which carefully distinguishes between values and objects. It is values that are typed in this model, and operations of the type work explicitly on the values. Objects are accessible only via reference values. Objects are described via descriptors called templates, which ultimately yield reference type values. Operations, both primitive and user-defined, are part of a “machine interface,” and all executable language constructs can ultimately be defined as explicit operations of the interface. Importantly, these operations must respect the typing constraints imposed by both the primitive types and the user extensions. The interactions of definition facility, storage model, and execution model are illustrated via a series of examples in which commonly user data constructs are defined. View full abstract»

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  • Recent Papers by IBM Authors

    Page(s): 783 - 788
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (522 KB)  

    First Page of the Article
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  • Recent IBM Patents

    Page(s): 789
    Save to Project icon | PDF file iconPDF (115 KB)  
    Freely Available from IEEE
  • Authors

    Page(s): 790 - 793
    Save to Project icon | PDF file iconPDF (428 KB)  
    Freely Available from IEEE
  • Author Index for Papers in Volume 24

    Page(s): 794 - 797
    Save to Project icon | PDF file iconPDF (275 KB)  
    Freely Available from IEEE
  • Subject Index for Papers in Volume 24

    Page(s): 798 - 800
    Save to Project icon | PDF file iconPDF (249 KB)  
    Freely Available from IEEE

Aims & Scope

The IBM Journal of Research and Development is a peer-reviewed technical journal, published bimonthly, which features the work of authors in the science, technology and engineering of information systems.

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Clifford A. Pickover
IBM T. J. Watson Research Center