jitcc

Toy JIT C compiler library

Just-in-time C compiler heavily based and inspired by chibicc and LLVM 2.0.

Disclaimer: This is an unfinished experiment. It should not be used in a production environment or for any other serious use. You are better off using any other C (JIT) compiler.

Goal

There is no end goal other than learn how compilers work. In other words, it's just another project for me to abandon :)

What's not included:

• C Preprocessor
  • WIP; missing include_next, etc.
• Optional C99 features (VLAs, atomic ops, etc.)
• GNU C extensions
• Many other major or minor things I cannot recall at the moment. Don't expect your random C code to be compilable!

What's included:

• C frontend (jcc.c)
  • Heavily based on chibicc with some changes/fixes from slimcc
  • I've rewritten most of the code for educational purposes but if you are familiar with chibicc/slimcc you'll be able to navigate your way through the code.
• High-level Intermediate Representation (jir.c, jir_pass.c, jir_gen.c)
  • IR inspired by LLVM 2.0.
  • It's not LLVM! It's more or less what I understood by reading LLVM's source code and adapting it to what I thought I needed.
• Machine-level Intermediate Representation (jmir.c, jmir_pass.c, jmir_gen.c)
  • It only supports x86_64 (AMD64).
  • There is no provision to support anything else at the moment.
  • Some ABI specific constructs might be unintentionally hardcoded for Windows x64 ABI, because I develop on Windows and this is my main target.
• JIT assembler (jit.c)
  • Simple x86_64 instruction encoder.

3rd party code

• chibicc is copyright (c) 2019 Rui Ueyama
• slimcc is copyright (c) 2023 Hsiang-Ying Fu
• stb_sprintf.h is copyright (c) 2017 Sean Barrett
• vurtun/json.h is written by Micha Mettke
• c-testsuite is copyright (c) 2018 Andrew Chambers
• any other 3rd party code is copyright by their respective owners