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

Summary

LIT is a general-purpose testing framework that can not only be used inside LLVM, but also arbitrary projects with little effort. This chapter tried to prove this point by showing you how to integrate LIT into an out-of-tree project without even needing to build LLVM. Second, we saw FileCheck – a powerful pattern checker that's used by many LIT test scripts. These skills can reinforce the expressiveness of your testing scripts. Finally, we presented you with the TestSuite framework, which is suitable for testing different kinds of program and complements the default LIT testing format.

In the next chapter, we will explore another supporting framework in the LLVM project: TableGen. We will show you that TableGen is also a general toolbox that can solve problems in out-of-tree projects, albeit almost being exclusively used by backend development in LLVM nowadays.