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 8: Working with Compiler Flags and Toolchains

In the previous chapter, we learned how to process Clang's AST – one of the most common formats for analyzing programs. In addition, we learned how to develop an AST plugin, which is an easy way to insert custom logic into the Clang compilation pipeline. This knowledge will help you augment your skillset for tasks such as source code linting or finding potential security vulnerabilities.

In this chapter, we are ascending from specific subsystems and looking at the bigger picture – the compiler driver and toolchain that orchestrate, configure, and run individual LLVM and Clang components according to users' needs. More specifically, we will focus on how to add new compiler flags and how to create a custom toolchain. As we mentioned in Chapter 5, Exploring Clang's Architecture, compiler drivers and toolchains are often under-appreciated and have long been ignored. However, without these two important...