Book Image

Learn LLVM 12

By : Kai Nacke
Book Image

Learn LLVM 12

By: Kai Nacke

Overview of this book

LLVM was built to bridge the gap between compiler textbooks and actual compiler development. It provides a modular codebase and advanced tools which help developers to build compilers easily. This book provides a practical introduction to LLVM, gradually helping you navigate through complex scenarios with ease when it comes to building and working with compilers. You’ll start by configuring, building, and installing LLVM libraries, tools, and external projects. Next, the book will introduce you to LLVM design and how it works in practice during each LLVM compiler stage: frontend, optimizer, and backend. Using a subset of a real programming language as an example, you will then learn how to develop a frontend and generate LLVM IR, hand it over to the optimization pipeline, and generate machine code from it. Later chapters will show you how to extend LLVM with a new pass and how instruction selection in LLVM works. You’ll also focus on Just-in-Time compilation issues and the current state of JIT-compilation support that LLVM provides, before finally going on to understand how to develop a new backend for LLVM. By the end of this LLVM book, you will have gained real-world experience in working with the LLVM compiler development framework with the help of hands-on examples and source code snippets.
Table of Contents (17 chapters)
Section 1 – The Basics of Compiler Construction with LLVM
Section 2 – From Source to Machine Code Generation
Section 3 –Taking LLVM to the Next Level

Chapter 4: Turning the Source File into an Abstract Syntax Tree

A compiler is typically divided into two parts: the frontend and the backend. In this chapter, we will implement the frontend of a programming language; that is, the part that deals with the source language. We will learn about the techniques real-world compilers use and apply them to our own programming languages.

We'll begin our journey by defining our programming language's grammar and end it with an abstract syntax tree (AST), which will become the basis for code generation. You can use this approach for every programming language that you would like to implement a compiler for.

In this chapter, you will learn about the following topics:

  • Defining a real programming language introduces you to the tinylang language, which is a subset of a real programming language, and for which you must implement a compiler frontend.
  • Creating the project layout, in which you will create the project layout...