Hacker's Guide to HHVM

This directory contains documentation on the internal architecture of HHVM, targeted at C++ developers looking to hack on HHVM itself.

HHBC spec
Frontend
- Parser
- Emitter
- HHBBC
- ...
VM Runtime
- Runtime data structures
  - Unit
  - Func
  - PreClass/Class
  - SrcKey
- Execution Context
- Bytecode interpreter
- Unwinder
- Treadmill
- Debugger
- ...
JIT Compiler
- Core concepts
- Optimization passes
- ...