lyn 0.0.3

Python bindings for GNU Lightning JIT

Lyn provides Python bindings for GNU Lightning, the light-weight just-in-time (JIT) compiler that translated to native machine code.

The code is hosted on https://github.com/cslarsen/lyn/ and is installable from https://pypi.python.org/pypi/lyn/.

“Lyn” is the Norwegian word for “lightning”.

NOTE: This project is currently in extremely early stages!

Status

As mentioned above, Lyn is fledgling: I’ve just spent a few hours on it, so almost nothing is supported and — in particular — I’ve only targeted x86-64 opcodes just yet.

In spite of this, I’ve managed to create a really simple program in Python that is JIT-compiled to native x86-64 machine code: A glorious function that returns the value of 123! Here’s the code:

#!/usr/bin/env python

from lyn import *

lib = Lightning()

with lib.state() as jit:
    jit.prolog()

    # The actual code
    jit.movi(Register.V0, 123)
    jit.retr(Register.V0)

    function = jit.emit_function()
    print("Should get 123 here: %s" % function())

I’m using ctypes for creating the bindings, which comes with some challenges: GNU Lightning is written in C, and relies heavily on compile-time macros that define machine specific opcodes, register values and so on. Because of this, it would be more natural to simply create bindings through a C extension. On the other hand, though, ctypes makes it possible to ship Lyn as a platform independent, pure Python source. I’ll chew on this for a while, and we’ll see what happens.

Installation

Either:

$ pip install lyn

or:

$ python setup.py install

Requirements

You need GNU Lightning version 2.1.0, built as a shared library.

Remember to configure GNU Lightning with the option --enable-shared. To use the disassembler, you should also add --enable-disassembler.

Author and license

Copyright (C) 2015 Christian Stigen Larsen

Distributed under the LGPL v2.1 or later. You are allowed to change the license on a particular copy to the LGPL v3.0, the GPL v2.0 or the GPL v3.0.