LibJS: Generate C++ bytecode instruction classes from a definition file

Browse source

This commit adds a new Bytecode.def file that describes all the LibJS
bytecode instructions.

From this, we are able to generate the full declarations for all C++
bytecode instruction classes, as well as their serialization code.

Note that some of the bytecode compiler was updated since instructions
no longer have default constructor arguments.

The big immediate benefit here is that we lose a couple thousand lines
of hand-written C++ code. Going forward, this also allows us to do more
tooling for the bytecode VM, now that we have an authoritative
description of its instructions.

Key things to know about:

- Instructions can inherit from one another. At the moment, everything
  simply inherits from the base "Instruction".

- @terminator means the instruction terminates a basic block.

- @nothrow means the instruction cannot throw. This affects how the
  interpreter interacts with it.

- Variable-length instructions are automatically supported. Just put an
  array of something as the last field of the instruction.

- The m_length field is magical. If present, it will be populated with
  the full length of the instruction. This is used for variable-length
  instructions.

...

This commit is contained in:

Andreas Kling 2025-11-20 22:14:50 +01:00 • committed by Andreas Kling

parent 84443e1de6

commit 003589db2d

Notes: github-actions[bot] 2025-11-21 08:47:47 +00:00

Author: https://github.com/awesomekling
Commit: 003589db2d
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/6888

12 changed files with 1975 additions and 4198 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

955

Libraries/LibJS/Bytecode/Interpreter.cpp

View file

File diff suppressed because it is too large Load diff