xdis 3.3.0

Python cross-version byte-code disassembler and marshal routines

xdis

Cross-Python bytecode Disassembler and Marshal routines

Introduction

The Python dis module allows you to disassemble bytecode from the same version of Python that you are running on. But what about bytecode from different versions?

That’s what this package is for. It can “marshal load” Python bytecodes from different versions of Python. The command-line routine pydisasm will show disassembly output using Python 3.5 disassembly conventions.

It accepts bytecodes from Python version 1.5 to 3.6 or so. The code requires Python 2.6 or later and has been tested on Python running versions 2.6, pypy-2.6.1 2.7, pypy-5.0.1, pypy-5.3.1, 3.2, 3.3, 3.4, 3.5 and 3.6.

Installation

This uses setup.py, so it follows the standard Python routine:

pip install -r requirements.txt
pip install -r requirements-dev.txt
python setup.py install # may need sudo
# or if you have pyenv:
python setup.py develop

A GNU makefile is also provided so make install (possibly as root or sudo) will do the steps above.

Testing

make check

A GNU makefile has been added to smooth over setting running the right command, and running tests from fastest to slowest.

If you have remake installed, you can see the list of all tasks including tests via remake --tasks.

Usage

Run

./bin/pydisasm -h

for usage help.

As a drop-in replacement for dis

xdis also provides some support as a drop in replacement for the the Python library dis module. This is may be desirable when you want to use the improved API from Python 3.4 or later from an earlier Python version.

For example:

>>> # works in Python 2 and 3
>>> import xdis.std as dis
>>> [x.opname for x in dis.Bytecode('a = 10')]
['LOAD_CONST', 'STORE_NAME', 'LOAD_CONST', 'RETURN_VALUE']

There may some small differences in output produced for formatted disassembly or how we show compiler flags. We expect you’ll find the xdis output more informative though.

See Also

• https://github.com/rocky/python-uncompyle6 : python bytecode deparsing