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

Implementing your scheduling model

In the previous section, we already covered a lot of the implementation details of the scheduling model while explaining how to understand it.

In this section, we cover what is missing, which is how to connect your scheduling model to the codegen infrastructure, and recommendations of how you should approach the implementation. Notice that we did not speak about running the TableGen backend that produces the scheduling information. This is because you already connected the needed TableGen backend, gen-subtarget, in Chapter 9.

Without further ado, let us start with connecting your scheduling model with the codegen infrastructure.

Connecting your scheduling model

For this section, let us assume you have already implemented your SchedMachineModel TableGen class.

At this point, you need to attach your scheduling model to the related processor model of your target (for instance, Haswell or Sapphire Rapids for x86) and connect the instantiation...