A wrapper script that can be used to conveniently check the assembly/LLVM IR of given C/C++ source. Example usage: ./decompile.py clang -emit-llvm -O2 test.cpp | less

decompile.py

#!/usr/bin/env python3

import os
import sys
import subprocess
import tempfile

import contextlib

@contextlib.contextmanager
def mktemp_contextmanager(*args, **kwargs):
    name = tempfile.mktemp(*args, **kwargs)
    yield name
    try:
        os.unlink(name)
    except FileNotFoundError:
        pass

def main():
    argv = sys.argv

    with mktemp_contextmanager(suffix=".o") as temp_name:
        extargs = []
        extargs.append(argv[1])
        extargs += ["-c", "-o", temp_name]
        extargs += argv[2:]

        try:
            subprocess.check_call(extargs)
        except subprocess.CalledProcessError:
            return 1

        if "-emit-llvm" in argv:
            if "-S" in argv:
                extargs = ["cat", temp_name]
            else:
                extargs = ["llvm-dis", "-o", "-", temp_name]
        else:
            if "-S" in argv:
                extargs = ["cat", temp_name]
            else:
                # assume ELF format
                extargs = ["objdump", "-d", "-Mintel", temp_name]

        try:
            subprocess.check_call(extargs)
        except subprocess.CalledProcessError:
            return 1

if __name__ == "__main__":
    sys.exit(main())