Writing Compilers and Interpreters: A Software Engineering Approach, 3rd Edition

Introduction xxi

Chapter 1 Introduction 1

Goals and Approach 1

What Are Compilers and Interpreters? 2

Comparing Compilers and Interpreters 4

The Picture Gets a Bit Fuzzy 5

Why Study Compiler Writing? 6

Conceptual Design 6

Syntax and Semantics 8

Lexical, Syntax, and Semantic Analyses 10

Chapter 2 Framework I: Compiler and Interpreter 11

Goals and Approach 11

Language-Independent Framework Components 12

Front End 13

Parser 16

Intermediate Tier 34

Back End 36

Pascal-Specific Front End Components 37

Pascal Parser 37

Pascal Scanner 39

A Front End Factory 41

Initial Back End Implementations 43

Interpreter 44

A Back End Factory 45

Program 2: Program Listings 46

Chapter 3 Scanning 55

Goals and Approach 55

Program 3: Pascal Tokenizer 57

Syntax Error Handling 65

How to Scan for Tokens 72

A Pascal Scanner 75

Pascal Tokens 77

Syntax Diagrams 80

Word Tokens 81

String Tokens 82

Special Symbol Tokens 85

Number Tokens 88

Chapter 4 The Symbol Table 97

Goals and Approach 97

Symbol Table Conceptual Design 98

The Symbol Table Stack 98

Symbol Table Interfaces 100

A Symbol Table Factory 105

Symbol Table Implementation 107

Program 4: Pascal Cross-Referencer I 113

Chapter 5 Parsing Expressions and Assignment Statements 121

Goals and Approach 121

Syntax Diagrams 122

Intermediate Code Conceptual Design 125

Intermediate Code Interfaces 126

An Intermediate Code Factory 129

Intermediate Code Implementation 130

Printing Parse Trees 135

Parsing Pascal Statements and Expressions 141

Parsing Statements 145

Parsing the Compound Statement 148

Parsing the Assignment Statement 149

Parsing Expressions 151

Program 5: Pascal Syntax Checker I 161

Chapter 6 Interpreting Expressions and Assignment Statements 167

Goals and Approach 167

Runtime Error Handling 168

Executing Assignment Statements and Expressions 170

The Statement Executor Subclasses 170

Executing Statements 173

Executing the Compound Statement 175

Executing the Assignment Statement 175

Executing Expressions 177

Program 6: Simple Interpreter I 184

Chapter 7 Parsing Control Statements 189

Goals and Approach 189

Syntax Diagrams 190

Error Recovery 191

Program 7: Syntax Checker II 192

Control Statement Parsers 193

Parsing Pascal Control Statements 198

Parsing the REPEAT Statement 198

Parsing the WHILE Statement 202

Parsing the FOR Statement 207

Parsing the IF Statement 214

Parsing the CASE Statement 219

Chapter 8 Interpreting Control Statements 233

Goals and Approach 233

Program 8: Simple Interpreter II 233

Interpreting Control Statements 234

Executing a Looping Statement 236

Executing the IF Statement 240

Executing the SELECT Statement 241

An Optimized SELECT Executor 245

Chapter 9 Parsing Declarations 249

Goals and Approach 249

Pascal Declarations 250

Types and the Symbol Table 253

Type Specification Interfaces 253

Pascal Type Specification Implementation 255

A Type Factory 260

Scope and the Symbol Table Stack 261

How Identifiers Are Defined 266

Predefined Types and Constants 268

Parsing Pascal Declarations 271

Parsing Constant Definitions 277

Parsing Type Definitions and Type Specifications 283

Parsing Variable Declarations 301

Program 9: Pascal Cross-Referencer II 306

Chapter 10 Type Checking 331

Goals and Approach 331

Type Checking 331

Type Checking Expressions 335

Type Checking Control Statements 350

Program 10: Pascal Syntax Checker III 358

Chapter 11 Parsing Programs, Procedures, and Functions 371

Goals and Approach 371

Program, Procedure, and Function Declarations 372

Nested Scopes and the Symbol Table Stack 375

New Declarations Parser Subclasses 378

Parsing a Program Declaration 382

Parsing Procedure and Function Declarations 382

Formal Parameter Lists 388

Parsing Procedure and Function Calls 394

Calls to Declared Procedures and Functions 398

Calls to the Standard Procedures and Functions 400

Actual Parameter Lists 408

Program 11: Pascal Syntax Checker IV 418

Chapter 12 Interpreting Pascal Programs 431

Goals and Approach 431

Runtime Memory Management 432

The Runtime Stack and Activation Records 432

The Runtime Display 436

Recursive Calls 439

Memory Management Interfaces and Implementation 440

The Memory Factory 459

Executing Statements and Expressions 460

The Executor Superclass 461

The Statement Executor 462

The Assignment and Expression Executors 469

Executing Procedure and Function Calls 478

Parameter Passing 478

Calling Procedures and Functions 478

Program 12-1: Pascal Interpreter 493

Chapter 13 An Interactive Source-Level Debugger 501

Goals and Approach 501

Machine-Level vs. Source-Level Debugging 502

Debugger Architecture 503

Runtime Data Input vs. Debugger Command Input 514

Creating a Command-Line Debugger 516

A Simple Command Language 517

Displaying Values 522

Parsing VariableNames 525

Executing Commands 529

Program 13-1: Command-Line Source-Level Debugger 540

Chapter 14 Framework II: An Integrated Development Environment (IDE) 543

Goals and Approach 544

The IDE Window 544

The Edit Window 545

The Debug Window 545

The Call Stack Window 547

The Console Window 548

Program 14: Pascal IDE 548

The IDE Process and the Debugger Process 549

The IDE Framework 549

Interprocess Communication 550

The Control Interface 560

The Debugger Process 566

Chapter 15 Jasmin Assembly Language and Code Generation for the Java Virtual Machine 577

Goals and Approach 577

Organization of the Java Virtual Machine 578

The Class Area 578

The Heap Area 579

The Java Runtime Stack 579

JVM Limitations 580

The Jasmin Assembly Language 581

Assembly Statements 581

Program Structure 593

Emitting Instructions 604

Load and Store Instructions 607

Data Manipulation Instructions 617

Control Instructions 620

Remaining Code Generation Methods 623

Chapter 16 Compiling Programs, Assignment Statements, and Expressions 625

Goals and Approach 625

Compiling Programs 626

Program Header 627

Class Constructor 627

Fields 627

Main Method 628

Code Generator Subclasses 629

Compiling Procedures and Functions 635

Parser and Symbol Table Changes 637

Generating Code for Procedures and Functions 639

Compiling Assignment Statements and Expressions 643

The Statement Code Generator 643

The Compound Statement Code Generator 645

The Assignment Statement Code Generator 646

The Expression Code Generator 648

The Pascal Runtime Library 655

Range Checking 655

Pascal Text Input 656

Building the Library 657

Program 16-1: Pascal Compiler I 657

Chapter 17 Compiling Procedure and Function Calls and String Operations 661

Goals and Approach 661

Compiling Procedure and Function Calls 662

Value Parameters and VAR Parameters 664

Calls to Declared Procedures and Functions 666

Calls to the Standard Procedures and Functions 678

The Pascal Runtime Library 691

Pascal Input Text 692

Building the Library 697

Compiling Strings and String Assignments 698

Allocating String Variables 698

String Assignments 701

String Comparisons 705

Program 17-1: Pascal Compiler II 711

Chapter 18 Compiling Control Statements, Arrays, and Records 719

Goals and Approach 719

Compiling Control Statements 719

Looping Statements 720

The IF Statement 730

The SELECT Statement 735

Compiling Arrays and Subscripted Variables 744

Allocating Memory for Arrays 744

Subscripted Variables in Expressions and Assignments 757

Compiling Records and Record Fields 767

Allocating Records 768

Record Fields in Expressions and Assignments 772

Program 18-1: Pascal Compiler III 777

Chapter 19 Additional Topics 791

Scanning 791

Deterministic Finite Automata (DFA) 791

Table-Driven Scanners 793

Syntax Notation 796

Backus-Naur Form (BNF) 796

Extended BNF (EBNF) 797

Grammars and Languages 797

Parsing 798

Top-Down Parsers 798

Bottom-Up Parsers 798

Context-Free and Context-Sensitive Grammars 800

Code Generation 800

Instruction Selection 800

Instruction Scheduling 801

Register Allocation 803

Code Optimization 803

Debugging Compilers and Optimizing Compilers 804

Speed Optimizations 804

Runtime Memory Management 807

Heap and Stack 807

Garbage Collection 808

Compiling Object-Oriented Languages 809

Method Overloading and Name Mangling 809

Inheritance 810

Virtual Methods 810

Compiler-Compilers 811

JavaCC 811

Lex and Yacc 813

Index 817