You're reading from LLVM Code Generation A deep dive into compiler backend development

Product type Paperback

Published in May 2025

Publisher Packt

ISBN-13 9781837637782

Length 608 pages

Edition 1st Edition

Languages

C++

Tools

LLVM

Concepts

Programming Language

Author (1):

Quentin Colombet

View More author details

Table of Contents (29) Chapters

Preface

1. Getting Started with LLVM

2. Building LLVM and Understanding the Directory Structure FREE CHAPTER

3. Contributing to LLVM

4. Compiler Basics and How They Map to LLVM APIs

5. Writing Your First Optimization

6. Dealing with Pass Managers

7. TableGen – LLVM Swiss Army Knife for Modeling

8. Middle-End: LLVM IR to LLVM IR

9. Understanding LLVM IR

10. Survey of the Existing Passes

11. Introducing Target-Specific Constructs

12. Hands-On Debugging LLVM IR Passes

13. Introduction to the Backend

14. Getting Started with the Backend

15. Getting Started with the Machine Code Layer

16. The Machine Pass Pipeline

17. LLVM IR to Machine IR

18. Getting Started with Instruction Selection

19. Instruction Selection: The IR Building Phase

20. Instruction Selection: The Legalization Phase

21. Instruction Selection: The Selection Phase and Beyond

22. Final Lowering and Optimizations

23. Instruction Scheduling

24. Register Allocation

25. Lowering of the Stack Layout

26. Getting Started with the Assembler

27. Other Books You May Enjoy

28. Index

LLVM IR API – cheat sheet

Now that you know the LLVM IR representation, we can use it to anchor the various APIs that you saw in this and previous chapters.

The result is the cheat sheet presented in Figure 7.3:

Figure 7.3: LLVM IR API cheat sheet

In Figure 7.3, we represented the scopes of the various classes, with their names framed in the top-right correct of the related scope. This cheat sheet shows four scopes, from innermost scope to outermost: Instruction, BasicBlock, Function, and Module. Within a scope, we showed a few methods, in italics, that you can call when you have a hold of the related instance, meaning you can call the methods in the BasicBlock scope if you hold a pointer on such an instance. The black arrows show what the results of the methods point to.

This cheat sheet is obviously not exhaustive, but we believe it should give you a better grasp of how LLVM IR is structured and how it maps to the related APIs.

From this point forward...