Programming Language Pragmatics

Transcription

1 Programming Language Pragmatics THIRD EDITION Michael L. Scott Department of Computer Science University of Rochester ^ШШШШШ AMSTERDAM BOSTON HEIDELBERG LONDON, '-*i» ЩЛ< ^ ' m H NEW YORK «OXFORD «PARIS»SAN DIEGO ^k^b V\A jfce f$fa SAN FRANCISCO SINGAPORE SYDNEY TOKYO ^^^И к.^ ELSEVIER Morgan Kaufmann Publishers is an imprint of Elsevier MORGAN KAUFMANN PUBLISHERS

2 Contents Foreword Preface xxi xxiii FOUNDATIONS з 1 Introduction 5 I. I The Art of Language Design The Programming Language Spectrum Why Study Programming Languages? Compilation and Interpretation Programming Environments An Overview of Compilation Lexical and Syntax Analysis Semantic Analysis and Intermediate Code Generation Target Code Generation Code Improvement Summary and Concluding Remarks Exercises Explorations Bibliographic Notes 39 2 Programming Language Syntax Specifying Syntax: Regular Expressions and Context-Free Grammars Tokens and Regular Expressions Context-Free Grammars Derivations and Parse Trees 48

3 2.2 Scanning Generating a Finite Automaton Scanner Code Table-Driven Scanning Lexical Errors Pragmas 2.3 Parsing Recursive Descent Table-Driven Тор-Down Parsing Bottom-Up Parsing Syntax Errors 2.4 Theoretical Foundations Finite Automata Push-Down Automata Grammar and Language Classes 2.5 Summary and Concluding Remarks 2.6 Exercises 2.7 Explorations 2.8 Bibliographic Notes Names, Scopes, and Bindings 3.1 The Notion of Binding Time 3.2 Object Lifetime and Storage Management Static Allocation Stack-Based Allocation Heap-Based Allocation Garbage Collection 3.3 Scope Rules Static Scoping Nested Subroutines Declaration Order Modules Module Types and Classes Dynamic Scoping 3.4 Implementing Scope Symbol Tables Association Lists and Central ReferenceTabl 3.5 The Meaning of Names within a Scope Aliases

4 3.5.2 Overloading Polymorphism and Related Concepts 3.6 The Binding of Referencing Environments Subroutine Closures Fi rst-class Values and Unlimited Extent Object Closures 3.7 Macro Expansion 3.8 Separate Compilation Separate Compilation in С Packages and Automatic Header Inference Module Hierarchies 3.9 Summary and Concluding Remarks 3.10 Exercises 3.1 I Explorations 3.12 Bibliographic Notes 4 Semantic Analysis 4.1 The Role of the Semantic Analyzer 4.2 Attribute Grammars 4.3 Evaluating Attributes 4.4 Action Routines 4.5 Space Management for Attributes Bottom-Up Evaluation Тор-Down Evaluation 4.6 Decorating a Syntax Tree 4.7 Summary and Concluding Remarks 4.8 Exercises 4.9 Explorations 4.10 Bibliographic Notes 5 Target Machine Architecture 5.1 The Memory Hierarchy 5.2 Data Representation Integer Arithmetic Floating-Point Arithmetic

5 5.3 Instruction Set Architecture Addressing Modes Conditions and Branches 5.4 Architecture and Implementation Microprogramming Microprocessors RISC Multithreading and Multicore Two Example Architectures: The x86 and MIPS 5.5 Compiling for Modern Processors Keeping the Pipeline Full Register Allocation 5.6 Summary and Concluding Remarks 5.7 Exercises 5.8 Explorations 5.9 Bibliographic Notes s i CORE ISSUES IN LANGUAGE DESIGN 6 Control Flow 6.1 Expression Evaluation. I Precedence and Associativity.2 Assignments.3 Initialization.4 Ordering within Expressions.5 Short-Circuit Evaluation 6.2 Structured and Unstructured Flow Structured Alternatives to goto Continuations 6.3 Sequencing 6.4 Selection Short-Circuited Conditions Case/Switch Statements 6.5 Iteration Enumeration-Controlled Loops Combination Loops

6 6.5.3 Iterators Generators in Icon Logically Controlled Loops 6.6 Recursion Iteration and Recursion Applicative- and Normal-Order Evaluation 6.7 Nondeterminacy 6.8 Summary and Concluding Remarks 6.9 Exercises 6.10 Explorations 6.1 I Bibliographic Notes Data Types 7.1 Type Systems Type Checking Polymorphism The Meaning of "Type Classification of Types Orthogonality 7.2 Type Checking Type Equivalence Type Compatibility Type Inference The ML Type System 7.3 Records (Structures) and Variants (Unions) Syntax and Operations Memory Layout and Its Impact With Statements Variant Records (Unions) 7.4 Arrays Syntax and Operations Dimensions, Bounds, and Allocation Memory Layout 7.5 Strings 7.6 Sets 7.7 Pointers and Recursive Types Syntax and Operations

7 xiv Contents 7.8 Lists Dangling References Garbage Collection 7.9 Files and Input/Output Interactive I/O File-Based I/O Text I/O 7.10 Equality Testing and Assignment 7.1 I Summary and Concluding Remarks 7.12 Exercises 7.13 Explorations 7.14 Bibliographic Notes Subroutines and Control Abstraction Review of Stack Layout Calling Sequences Displays Case Studies: С on the MIPS; Pascal on the x Register Windows In-Line Expansion Parameter Passing Parameter Modes Call-by-Name Special-Purpose Parameters Function Returns Generic Subroutines and Modules Implementation Options Generic Parameter Constraints Implicit Instantiation Generics in C++, Java, and C# Exception Handling Defining Exceptions Exception Propagation Implementation of Exceptions Coroutines Stack Allocation Transfer 432

8 Contents XV Implementation of Iterators Discrete Event Simulation Events Sequential Handlers Thread-Based Handlers Summary and Concluding Remarks Exercises Explorations I Bibliographic Notes 447 Data Abstraction and Object Orientation Object-Oriented Programming Encapsulation and Inheritance Modules Classes Nesting (Inner Classes) Type Extensions Extending without Inheritance Initialization and Finalization Choosing a Constructor References and Values Execution Order Garbage Collection Dynamic Method Binding Virtual and Nonvirtual Methods Abstract Classes Member Lookup Polymorphism Object Closures Multiple Inheritance Semantic Ambiguities Replicated Inheritance Shared Inheritance Mix-ln Inheritance Object-Oriented Programming Revisited The Object Model of Smalltalk Summary and Concluding Remarks 494

9 xvi Contents 9.8 Exercises Explorations Bibliographic Notes 499 ALTERNATIVE PROGRAMMING MODELS Functional Languages Historical Origins Functional Programming Concepts A Review/Overview of Scheme Bindings Listsand Numbers Equality Testing and Searching Control Flow and Assignment Programs as Lists Extended Example: DFA Simulation Evaluation Order Revisited Strictness and Lazy Evaluation I/O: Streams and Monads Higher-Order Functions Theoretical Foundations Lambda Calculus Control Flow Structures Functional Programming in Perspective Summary and Concluding Remarks Exercises Explorations Bibliographic Notes 543 I I Logic Languages 545 I I. I Logic Programming Concepts Prolog 547 I Resolution and Unification 549 I Lists 550

10 Contents xvii I Arithmetic 551 I Search/Execution Order 552 I Extended Example: Tic-Tac-Toe 554 I Imperative Control Flow 557 I Database Manipulation 561 I 1.3 Theoretical Foundations I Clausal Form Limitations Skolemization Logic Programming in Perspective 566 I Parts of Logic Not Covered 566 I Execution Order Negation and the "Closed World" Assumption Summary and Concluding Remarks 570 I 1.6 Exercises 571 I 1.7 Explorations 573 I 1.8 Bibliographic Notes Concurrency Background and Motivation The Case for Multithreaded Programs Multiprocessor Architecture Concurrent Programming Fundamentals Communication and Synchronization Languages and Libraries Thread Creation Syntax Implementation of Threads Implementing Synchronization Busy-Wait Synchronization Nonblocking Algorithms Memory Consistency Models Scheduler Implementation Semaphores Language-Level Mechanisms Monitors Conditional Critical Regions Synchronization in Java 626

11 xviii Contents Transactional Memory Implicit Synchronization Message Passing Naming Communication Partners Sending Receiving Remote Procedure Call Summary and Concluding Remarks Exercises Explorations Bibliographic Notes Scripting Languages What Is a Scripting Language? Common Characteristics Problem Domains Shell (Command) Languages Text Processing and Report Generation 663 I Mathematics and Statistics 667 I "Glue" Languages and General-Purpose Scripting Extension Languages Scripting the World Wide Web CGI Scripts Embedded Server-Side Scripts Client-Side Scripts Java Applets XSLT Innovative Features Names and Scopes String and Pattern Manipulation Data Types Object Orientation Summary and Concluding Remarks Exercises Explorations Bibliographic Notes 724

12 Contents xix A CLOSER LOOK AT IMPLEMENTATION Building a Runnable Program Back-End Compiler Structure A Plausible Set of Phases Phases and Passes Intermediate Forms Diana The gcc IFs Stack-Based Intermediate Forms Code Generation An Attribute Grammar Example Register Allocation Address Space Organization Assembly Emitting Instructions Assigning Addresses to Names Linking Relocation and Name Resolution Type Checking Dynamic Linking Position-Independent Code Fully Dynamic (Lazy) Linking Summary and Concluding Remarks Exercises Explorations Bibliographic Notes Run-time Program Management Virtual Machines The Java Virtual Machine The Common Language Infrastructure Late Binding of Machine Code Just-in-Time and Dynamic Compilation Binary Translation 791

13 XX Contents Binary Rewriting Mobile Code and Sandboxing 15.3 Inspection/Introspection Reflection Symbolic Debugging Performance Analysis 15.4 Summary and Concluding Remarks 15.5 Exercises 15.6 Explorations 15.7 Bibliographic Notes 16 Code Improvement A В С 16.1 Phases of Code Improvement 16.2 Peephole Optimization 16.3 Redundancy Elimination in Basic Blocks A Running Example Value Numbering 16.4 Global Redundancy and Data Flow Analysis SSA Form and Global Value Numbering Global Common Subexpression Elimination 16.5 Loop Improvement I Loop Invariants Induction Variables 16.6 Instruction Scheduling 16.7 Loop Improvement II Loop Unrolling and Software Pipelining Loop Reordering 16.8 Register Allocation 16.9 Summary and Concluding Remarks Bibliographic Notes Programming Languages Mentioned Language Design and Language Implementation Numbered Examples Bibliography Index