DOCSLIB.ORG

Introduction to the Literature on Programming Language Design the Intended Audience

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Introduction to the Literature on Programming Language Design� the Intended Audience Intro duction to the Literature On Programming Language Design Gary T Leavens TR c Jan revised Jan Feb and July Keywords programming languages semantics typ e systems p olymorphism typ e theory data abstrac tion functional programming ob jectoriented programming logic programming declarative programming parallel and distributed programming languages CR Categories D Programming Techniques ApplicativeFunctional Programming D Programming Techniques Concurrent Programming D Programming Techniques Ob jectoriented Pro gramming D Programming Techniques Logic Programming D Software Engineering To ols and Techniques Mo dules and interfaces D Software Engineering Program Verication D Software Engineering Program Verication D Programming Languages Formal Denitions and Theory D Programming Languages Language Classications D Programming Languages Language Constructs and F eatures F Logics and Meaning of Programs Sp ecifying and verifying and reasoning ab out pro grams F Logics and Meaning of Programs Semantics of Programming Languages F Logics and Meaning of Programs Studies of Program Constructs H Database Management LanguagesDatabase p ersistent programming languages I Articial Intel ligence Programming Languages and Software c Gary T Leavens Permission is granted for you to make copies for educational and scholarly purp oses but not for direct commercial advantage provided this notice app ears on all copies All other rights reserved Department of Computer Science Atanaso Hall Iowa State University Ames Iowa USA Intro duction to the Literature On Programming Language Design Gary T Leavens Department of Computer Science Iowa State University Ames IA USA leavenscsiastateedu July Abstract This is an intro duction to the literature on programming language design and related topics It is intended to cite the most imp ortantwork and to provide a place for students to start a literature search This is a selective introduction to the literature on programming language design The intended audience is graduate students b eginning a study of programming languages Instead of trying to b e comprehensive references are given that are to works of lasting value uptodate surveys or that seem to b e imp ortant or interesting at the moment Besides references that haveintrinsic interest a few are included b ecause they are the original sources and are likely to b e referenced by others doing related work eg Chu To prob e an area more deeply start with the pap ers mentioned follow their references and also use the Science Citation Index to see what pap ers have referenced the ones mentioned As a general aid to nding pap ers many older references are reprinted in a collection called TUTORIAL Programming Language Design edited byAIWasserman and available from the IEEE Computer So ciety Was Readers with web browsers may also wanttolookatthefollowing web page titled Programming Language and Compiler Bibliographies nelanguagebibliographieshtml httpwwwcscmuedumleo However this tends to have b etter coverage of recenttechnical rep orts and its coverage of older journal pap ers and other published material is sp otty Generalities There are several excellent undergraduate texts on programming languages including PZSeb Set FWH Hen KamWatGJ MacTen Graduate texts include SK Sta Sch WinWat Mey Gor Volume B of the Handbook of Theoretical Computer Science contains many detailed surveys relevantto formal mo dels and semantics vL Journals include a substantial coverage of programming languages include ACM Transactions on Pro gramming Languages and Systems abbreviated TOPLAS ACM Letters on Programming Languages and Systems abbreviated LOPLAS ACM SIGPLAN Notices Computer Languages Pergamon Press Journal of Pro gramming Languages Chapman and Hall Information and Computation formerly Information and Control Academic Press and Acta Informatica SpringerVerlag Applied areas such as sp ecication and This work was supp orted in part by the National Science Foundation under Grants CCR CCR and CCR Naturally these judgements are p ersonal but it is hop ed that authors of that vast bulk of pap ers that are not cited here will not take oense verication have their own journals eg IEEE Transactions on Software Engineering Science of Computer Programming Formal Aspects of Computing Other journals can b e found by scanning the bibliography Conferences devoted to topics related to programming languages include the Annual ACM Symp osium on Principles of Programming Languages POPL the ACM SIGPLAN Conference on Programming Language Design and Implementation PLDI the ACM SIGPLAN International Conference on Functional Program ming formerly called the Symp osium on LISP and Functional Programming LFP and the ACM SIGPLAN Symp osium on Principles and Practice of Parallel Programming PPOPP Conferences with a more the oretical b ent include the IEEE Annual Symp osium on Logic in Computer Science LICS Mathematical Foundations of Programming Semantics MFPS the Europ ean Symp osium on Programming ESOP the International Collo quium on Automata Languages and Programming ICALP and the International Sym p osium on Mathematical Foundations of Computer Science Conferences not sp onsored by the ACM or IEEE are often available in the SpringerVerlag series of Lecture Notes in Computer Science LNCS The ab ove list do es not include conferences devoted to software engineering eg TAPSOFT or particular metho ds eg category theory where other imp ortantwork is found Both Hoare and Wirth have written guidelines for programming language designers Hoa Wir Floyds Turing Award lecture discusses his view of programming languages as capturing paradigms of pro gramming Flo Another viewp oint is that language design should pro ceed from semantic principles Ten Baca The truism that bad programs can b e written in any programming language is describ ed as Flons Axiom in a pap er written at the height of the structured programming controversy Flo Shaw and Wulf t out that language designers can provide reasonable defaults while still giving programmers the ability p oin to change them SW The idea of the expressiveness of a language is just starting to receive satisfactory formal treatments Fel Mit Semantics Some texts that cover many dierent approaches to semantics are NN Win SK Op erational Semantics Landins SECD machine is dened in his pap er The Mechanical Evaluation of Expressions Lan see also Hendersons b o ok Hen A more systematic style of op erational semantics based on rewrite rules is found in Plotkins structural op erational semantics Plo Hen Ast Several metacircular interpreters for variants of LISP are discussed in Steele and Sussmans pap er The Art of the Interpreter SSa An excellent and more readily accessible discussion is found in Ab elson and Sussmans b o ok ASS whichusesScheme A more detailed treatmentofinterpreters is found in Kam FWH See KdRB for an approach using the CLOS metaob ject proto col More recently structuring mechanisms for semantics based on monads MogWadWadhave lead to more mo dular structuring of denitional interpreters Ste LHJ Calculus A standard reference on Churchs calculus Chu is Barendregts b o ok Bar Informal intro ductions include Gor For the typ ed calculus see GLT or Mitb The use of calculus for describing programming languages and as the inspiration for programming language design has b een investigated by Landin Lan Lan Denotational Semantics A short summary of the denotational approach to programming language semantics Sco can b e found in Tennents article The Denotational Semantics of Programming Languages Ten A survey is found in Mos Intro ductory texts include Gor All WatSch An excellent text with mathematical depth is Gun Standard works on denotational semantics are the b o oks byStoy Sto and Schmidt Sch b oth of which oer a comprehensive and mathematical treatment Schmidts b o ok Sch can b e consulted for references to denotational descriptions of real languages To read some of the most technical works one will need some familiarity with category theory Lan Gol LS the following are go o d intro ductions that emphasize semantic applications Hoa BWa ALb PieWal Gun One can use a typ ed functional programming language such as Standard ML to implement a denotational semantics Two descriptions of this are WatMA Action semantics an osho ot of denotational semantics is describ ed in Wat and more fully in Mos Axiomatic Semantics An early presentation of axiomatic semantics is Hoares pap er An Axiomatic Basis for Computer Program ming Hoa An example of the use of axiomatic semantics to dene a programming language is Hoare and Wirths axiomatic denition of Pascal HW A b o ok on axiomatic semantics slanted towards programming lan guage theory as opp osed to verication is Hesselinks monograph Hes Foundational material that may help in reading this monograph is found in DS whichgoesover notational issues as well as the underlying mathematics Avery intro ductory tutorial on verication from the software engineering p ersp ective is LGchapter eloping a pro of of a program at the same time the program is b eing develop ed has b een The idea of dev elo quently advo cated by Dijkstra and Gries Dij Gri More recent treatments in this style advocate a calculational approach Mor Coh GS See Ala for an intro duction that discusses concurrent and distributed programs A survey of program verication for imp erative programs is Cou A language designed to supp ort program verication is Euclid LGH PHL Another such lan guage is Alphard SWL Sha Algebraic Semantics
Load more

Recommended publications
  • Four Lectures on Standard ML
    Mads Tofte March Lab oratory for Foundations of Computer Science Department of Computer Science Edinburgh University Four Lectures on Standard ML The following notes give an overview of Standard ML with emphasis placed on the Mo dules part of the language The notes are to the b est of my knowledge faithful to The Denition of Standard ML Version as regards syntax semantics and terminology They have b een written so as to b e indep endent of any particular implemen tation The exercises in the rst lectures can b e tackled without the use of a machine although having access to an implementation will no doubt b e b enecial The pro ject in Lecture presupp oses access to an implementation of the full language including mo dules At present the Edinburgh compiler do es not fall into this category the author used the New Jersey Standard ML compiler Lecture gives an introduction to ML aimed at the reader who is familiar with some programming language but do es not know ML Both the Core Language and the Mo dules are covered by way of example Lecture discusses the use of ML mo dules in the development of large programs A useful metho dology for programming with functors signatures and structures is presented Lecture gives a fairly detailed account of the static semantics of ML mo dules for those who really want to understand the crucial notions of sharing and signature matching Lecture presents a one day pro ject intended to give the student an opp ortunity of mo difying a nontrivial piece of software using functors signatures and structures
    [Show full text]
  • Understanding and Evolving the ML Module System
    Understanding and Evolving the ML Module System Derek Dreyer May 2005 CMU-CS-05-131 School of Computer Science Carnegie Mellon University Pittsburgh, PA 15213 Thesis Committee: Robert Harper (co-chair) Karl Crary (co-chair) Peter Lee David MacQueen (University of Chicago) Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy Copyright c 2005 Derek Dreyer This research was sponsored in part by the National Science Foundation under grant CCR-0121633 and EIA- 9706572, and the US Air Force under grant F19628-95-C-0050 and a generous fellowship. The views and conclusions contained in this document are those of the author and should not be interpreted as representing the official policies, either expressed or implied, of any sponsoring institution, the U.S. government or any other entity. Keywords: ML, module systems, type systems, functors, abstract data types, lambda calculus, recursive modules, singleton kinds Abstract The ML module system stands as a high-water mark of programming language support for data abstraction. Nevertheless, it is not in a fully evolved state. One prominent weakness is that module interdependencies in ML are restricted to be acyclic, which means that mutually recursive functions and data types must be written in the same module even if they belong conceptually in different modules. Existing efforts to remedy this limitation either involve drastic changes to the notion of what a module is, or fail to allow mutually recursive modules to hide type information from one another. Another issue is that there are several dialects of ML, and the module systems of these dialects differ in subtle yet semantically significant ways that have been difficult to account for in any rigorous way.
    [Show full text]
  • Lecture Notes in Computer Science 2566 Edited by G
    Lecture Notes in Computer Science 2566 Edited by G. Goos, J. Hartmanis, and J. van Leeuwen 3 Berlin Heidelberg New York Barcelona Hong Kong London Milan Paris Tokyo Torben Æ. Mogensen David A. Schmidt I. Hal Sudborough (Eds.) The Essence of Computation Complexity, Analysis, Transformation Essays Dedicated to Neil D. Jones 13 Series Editors Gerhard Goos, Karlsruhe University, Germany Juris Hartmanis, Cornell University, NY, USA Jan van Leeuwen, Utrecht University, The Netherlands Volume Editors Torben Æ. Mogensen University of Copenhagen, DIKU Universitetsparken 1, 2100 Copenhagen, Denmark E-mail: [email protected] David A. Schmidt Kansas State University, Department of Computing and Information Sciences 234 Nichols Hall, Manhattan, KS 66506 USA E-mail: [email protected] I. Hal Sudborough University of Texas at Dallas, Department of Computer Science P.O. Box 830688, Richardson, TX 75083 USA E-mail: [email protected] The illustration appearing on the cover of this book is the work of Daniel Rozenberg (DADARA). Cataloging-in-Publication Data applied for A catalog record for this book is available from the Library of Congress. Bibliographic information published by Die Deutsche Bibliothek. Die Deutsche Bibliothek lists this publication in the Deutsche Nationalbibliografie; detailed bibliographic data is available in the Internet at <http://dnb.ddb.de>. CR Subject Classification (1998): F.3, F.1, D.2 ISSN 0302-9743 ISBN 3-540-00326-6 Springer-Verlag Berlin Heidelberg New York This work is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, re-use of illustrations, recitation, broadcasting, reproduction on microfilms or in any other way, and storage in data banks.
    [Show full text]
  • A Simpli Ed Account of Polymorphic References 1 Introduction 2 a Language with Mutable Data Structures
    A Simpli ed AccountofPolymorphic References Rob ert Harp er Scho ol of Computer Science Carnegie Mellon University Pittsburgh, PA 15213-3891 Abstract A pro of of the soundness of Tofte's imp erativetyp e discipli ne with resp ect to a structured op erational semantics is given. The presentation is based on a semantic formalism that combines the b ene ts of the approaches considered byWright and Felleisen, and byTofte, leading to a particularly simple pro of of soundness of Tofte's typ e disciplin e. Keywords: formal semantics, functional programming, programming languages, typ e theory, refer- ences and assignment. 1 Intro duction The extension of Damas and Milner's p olymorphic typ e system for pure functional programs [2] to accomo- date mutable cells has proved to b e problematic. The nave extension of the pure language with op erations to allo cate a cell, and to retrieve and mo dify its contents is unsound [11]. The problem has received consid- erable attention, notably by Damas [3], Tofte [10,11], and LeroyandWeiss [7]. Tofte's solution is based on a greatest xed p oint construction to de ne the semantic typing relation [11] (see also [8]). This metho d has b een subsequently used by Leroy and Weiss [7]andTalpin and Jouvelot [9]. It was subsequently noted by Wright and Felleisen [13] that the pro of of soundness can b e substantially simpli ed if the argument is made by induction on the length of an execution sequence, rather than on the structure of the typing derivation. Using this metho d they establish the soundness of a restriction of the language to require that let-b ound expressions b e values.
    [Show full text]
  • The Definition of Standard ML, Revised
    The Definition of Standard ML The Definition of Standard ML (Revised) Robin Milner, Mads Tofte, Robert Harper and David MacQueen The MIT Press Cambridge, Massachusetts London, England c 1997 Robin Milner All rights reserved. No part of this book may be reproduced in any form by any electronic or mechanical means (including photocopying, recording, or information storage and retrieval) without permission in writing from the publisher. Printed and bound in the United States of America. Library of Congress Cataloging-in-Publication Data The definition of standard ML: revised / Robin Milner ::: et al. p. cm. Includes bibliographical references and index. ISBN 0-262-63181-4 (alk. paper) 1. ML (Computer program language) I. Milner, R. (Robin), 1934- QA76.73.M6D44 1997 005:1303|dc21 97-59 CIP Contents 1 Introduction 1 2 Syntax of the Core 3 2.1 Reserved Words . 3 2.2 Special constants . 3 2.3 Comments . 4 2.4 Identifiers . 5 2.5 Lexical analysis . 6 2.6 Infixed operators . 6 2.7 Derived Forms . 7 2.8 Grammar . 7 2.9 Syntactic Restrictions . 9 3 Syntax of Modules 12 3.1 Reserved Words . 12 3.2 Identifiers . 12 3.3 Infixed operators . 12 3.4 Grammar for Modules . 13 3.5 Syntactic Restrictions . 13 4 Static Semantics for the Core 16 4.1 Simple Objects . 16 4.2 Compound Objects . 17 4.3 Projection, Injection and Modification . 17 4.4 Types and Type functions . 19 4.5 Type Schemes . 19 4.6 Scope of Explicit Type Variables . 20 4.7 Non-expansive Expressions . 21 4.8 Closure .
    [Show full text]
  • Implementation of the Typed Call-By-Value Λ-Calculus Using a Stack of Regions
    Implementation of the Typed Call-by-Value λ-calculus using a Stack of Regions Mads Tofte, University of Copenhagen∗ Jean-Pierre Talpin, European Computer-Industry Research Center † Abstract from the source program. Heap-based schemes are less eager to reuse memory. Generational garbage collec- We present a translation scheme for the polymorphi- tion collects young objects when the allocation space cally typed call-by-value λ-calculus. All runtime val- is used up. Hayes[11] discusses how to reclaim large, ues, including function closures, are put into regions. old objects. The store consists of a stack of regions. Region in- Garbage collection can be very fast. Indeed, there ference and effect inference are used to infer where is a much quoted argument that the amortized cost of regions can be allocated and de-allocated. Recursive copying garbage collection tends to zero, as memory functions are handled using a limited form of polymor- tends to infinity[2, page 206]. Novice functional pro- phic recursion. The translation is proved correct with grammers often report that on their machines, mem- respect to a store semantics, which models a region- ory is a constant, not a variable, and that this constant based run-time system. Experimental results suggest has to be uncomfortably large for their programs to that regions tend to be small, that region allocation is run well. The practical ambition of our work is to frequent and that overall memory demands are usually reduce the required size of this constant significantly. modest, even without garbage collection. We shall present measurements that indicate that our translation scheme holds some promise in this respect.
    [Show full text]
  • Tips for Computer Scientists Standard ML (Revised)
    Tips for Computer Scientists on Standard ML (Revised) Mads Tofte August 30, 2009 This document and all examples in it are available from http://www.itu.dk/people/tofte Preface Contents This note is inspired by a brilliant piece of writ- 1 Numbers 1 ing, entitled Tips for Danes on Punctuation in 2 Overloaded Arithmetic Operators 1 English, by John Dienhart, Department of En- 3 Strings 1 glish, Odense University (1980). In a mere 11 4 Lists 1 pages, Dienhart’s lucid writing gives the reader 5 Expressions 1 the impression that punctuation in English is 6 Declarations 1 pretty easy and that any Dane can get it right 7 Function Values 2 in an afternoon or so. 8 Constructed Values 3 In the same spirit, this note is written for col- 9 Patterns 4 leagues and mature students who would like to 10 Pattern Matching 5 get to know Standard ML without spending too 11 Function-value Bindings (revisited) 6 much time on it. It is intended to be a relaxed 12 Function Application 6 stroll through the structure of Standard ML, with 13 Type Expressions 7 plenty of small examples, without falling into 14 Type Abbreviations 7 the trap of being just a phrase book. 15 Datatype Declarations 7 I present enough of the grammar that the 16 Exceptions 8 reader can start programming in Standard ML, 17 References 9 should the urge arise. 18 Procedures 10 The full grammar and a formal definition of 19 Input and Output 10 the semantics can be found in the 1997 language 20 The top-level loop 11 definition[2].
    [Show full text]
  • A Retrospective on Region-Based Memory Management
    Higher-Order and Symbolic Computation, 17, 245–265, 2004 c 2004 Kluwer Academic Publishers. Manufactured in The Netherlands. A Retrospective on Region-Based Memory Management MADS TOFTE [email protected] LARS BIRKEDAL∗ [email protected] MARTIN ELSMAN [email protected] NIELS HALLENBERG [email protected] The IT University of Copenhagen, Denmark Abstract. We report on our experience with designing, implementing, proving correct, and evaluating a region- based memory management system. Keywords: dynamic storage management, regions, Standard ML 1. Introduction Originally, Region-based Memory Management was conceived as a purely theoretical idea intended to solve a practical problem in the context of Standard ML, namely inventing a dynamic memory management discipline that is less space demanding and more predictable than generic garbage collection techniques, such as generational garbage collection. Over the subsequent nine years, considerable effort has been devoted to refining the idea, proving it correct, and investigating whether it worked in practice. The practical experiments revealed weaknesses, which led to new program analyses, new theory, and yet more experimentation. In short, we have sought to work on memory management as an experimental science: the work should be scientific in the sense that it should rest on a solid mathematical foundation and it should be experimental in the sense that it should be tested against competing state-of-the-art implementation technology. The purpose of this paper is to step back and consider the process as a whole. We first describe the main technical developments, with an emphasis on what motivated the developments. We then summarise what we think has gone well and what has not gone so well.
    [Show full text]
  • A Region Inference Algorithm
    A Region Inference Algorithm MADS TOFTE University of Copenhagen and LARS BIRKEDAL Carnegie Mellon University Region Inference is a program analysis which infers lifetimes of values. It is targeted at a runtime model in which the store consists of a stack of regions and memory management predominantly consists of pushing and popping regions, rather than performing garbage collection. Region Infer- ence has previously been specified by a set of inference rules which formalize when regions may be allocated and deallocated. This article presents an algorithm which implements the specification. We prove that the algorithm is sound with respect to the region inference rules and that it always terminates even though the region inference rules permit polymorphic recursion in regions. The algorithm is the result of several years of experiments with region inference algorithms in the ML Kit, a compiler from Standard ML to assembly language. We report on practical experience with the algorithm and give hints on how to implement it. Categories and Subject Descriptors: D.3.3 [Programming Languages]: Language Constructs and Features—dynamic storage management; F.3.3 [Logics and Meanings of Programs]: Studies of Program Constructs—functional constructs; type structure General Terms: Algorithms, Reliability, Theory Additional Key Words and Phrases: Regions, Standard ML 1. INTRODUCTION Most programming languages have some mechanism for allocation and deallocation of dynamic data structures. In the Algol stack discipline [Dijkstra 1960; Naur 1963], every point of allocation is matched by a point of deallocation; these points are easily identified in the program text, which helps reasoning about memory usage. However, the pure stack discipline is rather restrictive.
    [Show full text]
  • Paper in Order to Obtain a Similar Soundness and Completeness Result for Modular Type Classes
    Principal Type Schemes for Modular Programs Derek Dreyer and Matthias Blume Toyota Technological Institute at Chicago fdreyer,[email protected] Abstract. Two of the most prominent features of ML are its expres- sive module system and its support for Damas-Milner type inference. However, while the foundations of both these features have been studied extensively, their interaction has never received a proper type-theoretic treatment. One consequence is that both the official Definition and the alternative Harper-Stone semantics of Standard ML are difficult to imple- ment correctly. To bolster this claim, we offer a series of short example programs on which no existing SML typechecker follows the behavior prescribed by either formal definition. It is unclear how to amend the implementations to match the definitions or vice versa. Instead, we pro- pose a way of defining how type inference interacts with modules that is more liberal than any existing definition or implementation of SML and, moreover, admits a provably sound and complete typechecking algo- rithm via a straightforward generalization of Algorithm W. In addition to being conceptually simple, our solution exhibits a novel hybrid of the Definition and Harper-Stone semantics of SML, and demonstrates the broader relevance of some type-theoretic techniques developed recently in the study of recursive modules. 1 Introduction The standard way of defining the static semantics of languages with type in- ference is to give a set of declarative Curry-style typing rules that assign types to untyped terms. Since these rules are typically written in a nondeterministic fashion, it is not prima facie decidable whether a term can be assigned a type.
    [Show full text]
  • Title: Region-Based Memory Management1 Authors: Mads Tofte and Jean-Pierre Talpin a Liation: Mads Tofte: Department of Computer
    Title RegionBased Memory Management Authors Mads Tofte and JeanPierre Talpin Aliation Mads Tofte Department of Computer Science Universityof Cop enhagen JeanPierre Talpin IRISA Campus de Beaulieu France An earlier version of this work was presented at the st ACM SIGPLANSIGACT Sym p osium on Principles of Programming Languages Portland Oregon January Abstract This pap er describ es a memory management disciplin e for programs that p erform dynamic memory allo cation and deallo cation At runtime all values are put into regions The store consists of a stack of regions All p oints of region allo cation and deallo cation are inferred automatically using a typ e and eect based program analysis The scheme do es not assume the presence of a garbage collector The scheme was rst presented byTofte and Talpin subse quently it has b een tested in The ML Kit with Regions a regionbased garbagecollection free implementation of the Standard ML Core language which includes recursive datatyp es higherorder functions and up datable references Birkedal et al Elsman and Hallenb erg This pap er denes a regionbased dynamic semantics for a skeletal pro gramming language extracted from Standard ML We present the inference system which sp ecies where regions can b e allo cated and deallo cated and a detailed pro of that the system is sound with resp ect to a standard se mantics We conclude by giving some advice on how to write programs that run well on a stack of regions based on practical exp erience with the ML Kit Intro duction Computers have nite memory
    [Show full text]
  • Typed Regions for Tag-Free Garbage Collection
    Typed Regions for Tag-Free Garbage Collection Martin Elsman⋆ IT University of Copenhagen. Glentevej 67, DK-2400 Copenhagen NV, Denmark. Email: [email protected] October, 2002 Abstract. This paper presents an extension to the Tofte-Talpin region type system, which makes it possible to combine region-based memory management with a partly tag-free garbage collection algorithm. The memory discipline is implemented for Standard ML in the ML Kit com- piler. Experiments show that, for a range of benchmark programs, the discipline improves performance, both with respect to memory usage and execution time. 1 Introduction In implementations of languages that support dynamic reference tracing garbage collection, such as most Java and ML implementations, tags are often used to distinguish between different types of values at runtime. The use of tags imposes a memory overhead, however, which for the most commonly used data structures, such as tuples, lists, and trees, can be as large as one third of the total memory usage. In this paper we present a memory discipline that integrates region-based memory management and reference tracing garbage collection in such a way that tagging of commonly used values such as tuples and lists is avoided. In the Tofte-Talpin region typing rules [18], two values are forced into the same region, only if their types are identical. This property suggests that, in systems based on the Tofte-Talpin region typing rules, tags to distinguish differ- ent types of values at runtime can be moved from individual values to the level of regions. We show that this “Big Bag of Pages” approach to avoid tagging improves memory usage and execution time for many programs.
    [Show full text]