Introduction to Compilers and Language Design Textbook

A Project-Based Approach to Compiler Construction

Prof. Douglas Thain of the University of Notre Dame has released the second edition of Introduction to Compilers and Language Design, a free online textbook designed to guide students through the process of building a working compiler from scratch. The book is specifically structured as a one-semester introduction, enabling readers to translate a C-like language into functional X86 or ARM assembly language.

Target Audience and Prerequisites

This textbook is most suitable for undergraduate computer science students who possess a foundational knowledge of the following areas:

• Programming in C: Practical experience with the C language is required.
• Data Structures: Completion of coursework in data structures.
• Computer Architecture: A basic understanding of how computer hardware operates.

Curriculum Structure and Technical Scope

The textbook is organized into 12 chapters and three appendices, covering the full pipeline of compiler construction. The curriculum moves from the initial analysis of source code to the final generation of machine-executable code.

Frontend Analysis

• Scanning and Parsing: Chapters 3, 4, and 5 cover the conversion of source text into tokens and the construction of a parser to handle the language's grammar.
• Abstract Syntax Tree (AST): Chapter 6 focuses on the representation of the program's structure in an AST.
• Semantic Analysis: Chapter 7 addresses type checking and ensuring the program adheres to the language's semantic rules.

Backend Generation

• Intermediate Representation (IR): Chapter 8 introduces the bridge between the high-level source and low-level machine code.
• Memory Organization: Chapter 9 explains how the compiler manages memory for the program.
• Laying the Groundwork for Assembly: Chapter 10 covers the assembly language itself, while Chapter 11 focuses on the actual code generation process.
• Optimization: Chapter 12 provides an introduction to optimizing the generated code for better performance.

Practical Resources

• The B-Minor Language: Appendix B defines the specific C-like language used throughout the book.
• Code Examples: A companion GitHub repository (compilerbook-examples) provides scanners, parsers, starter code for the project compiler, and test cases for each stage of the pipeline (scanner, parser, typechecker, and code generator).

Community Insights and Critiques

While the textbook is highly praised for its pedagogical approach, community discussions on Hacker News highlight several perspectives on its scope and content:

"Took Dr. Thain's compilers class in college! It was the best. He's an excellent instructor, and the course project made me build a working C-style compiler step by step."

Some readers noted that the book focuses heavily on the practical implementation of a compiler rather than the theoretical aspects of language design. One commenter observed that the table of contents suggests it is more of an "intro to compilers" than a comprehensive guide to "language design."

Other users suggested supplementing the material with projects like C4 (a tiny, self-compiling C-subset compiler) to provide a base for further exercises in extending the language.