Book Image

LLVM Techniques, Tips, and Best Practices Clang and Middle-End Libraries

By : Min-Yih Hsu
Book Image

LLVM Techniques, Tips, and Best Practices Clang and Middle-End Libraries

By: Min-Yih Hsu

Overview of this book

Every programmer or engineer, at some point in their career, works with compilers to optimize their applications. Compilers convert a high-level programming language into low-level machine-executable code. LLVM provides the infrastructure, reusable libraries, and tools needed for developers to build their own compilers. With LLVM’s extensive set of tooling, you can effectively generate code for different backends as well as optimize them. In this book, you’ll explore the LLVM compiler infrastructure and understand how to use it to solve different problems. You’ll start by looking at the structure and design philosophy of important components of LLVM and gradually move on to using Clang libraries to build tools that help you analyze high-level source code. As you advance, the book will show you how to process LLVM IR – a powerful way to transform and optimize the source program for various purposes. Equipped with this knowledge, you’ll be able to leverage LLVM and Clang to create a wide range of useful programming language tools, including compilers, interpreters, IDEs, and source code analyzers. By the end of this LLVM book, you’ll have developed the skills to create powerful tools using the LLVM framework to overcome different real-world challenges.
Table of Contents (18 chapters)
1
Section 1: Build System and LLVM-Specific Tooling
6
Section 2: Frontend Development
11
Section 3: "Middle-End" Development

Chapter 2: Exploring LLVM's Build System Features

In the previous chapter, we saw that LLVM's build system is a behemoth: it contains hundreds of build files with thousands of interleaving build dependencies. Not to mention, it contains targets that require custom build instructions for heterogeneous source files. These complexities drove LLVM to adopt some advanced build system features and, more importantly, a more structural build system design. In this chapter, our goal will be to learn about some important directives for the sake of writing more concise and expressive build files when doing both in-tree and out-of-tree LLVM developments.

In this chapter, we will cover the following main topics:

  • Exploring a glossary of LLVM's important CMake directives
  • Integrating LLVM via CMake in out-of-tree projects