Hi, Here are some progress on my astoptimizer project. If you are interested by the optimizer, run it on your own project or help me to implement more optimizations.
http://pypi.python.org/pypi/astoptimizer https://bitbucket.org/haypo/astoptimizer --- The last version (0.3) works on Python 2.6-3.3 and implements the following optimizations: * Call builtin functions if arguments are constants. Examples: - len("abc") => 3 - ord("A") => 65 * Call methods of builtin types if the object and arguments are constants. Examples: - u"h\\xe9ho".encode("utf-8") => b"h\\xc3\\xa9ho" - "python2.7".startswith("python") => True - (32).bit_length() => 6 - float.fromhex("0x1.8p+0") => 1.5 * Call functions of math and string modules for functions without border effect. Examples: - math.log(32) / math.log(2) => 5.0 - string.atoi("5") => 5 * Format strings for str%args and print(arg1, arg2, ...) if arguments are constants and the format string is valid. Examples: - "x=%s" % 5 => "x=5" - print(1.5) => print("1.5") * Simplify expressions. Examples: - not(x in y) => x not in y - 4 and 5 and x and 6 => x and 6 * Loop: replace range() with xrange() on Python 2, and list with tuple. Examples: - for x in range(n): ... => for x in xrange(n): ... - for x in [1, 2, 3]: ... => for x in (1, 2, 3): ... * Evaluate unary and binary operators, subscript and comparaison if all arguments are constants. Examples: - 1 + 2 * 3 => 7 - not True => False - "abc" * 3 => "abcabcabc" - abcdef[:3] => abc - (2, 7, 3)[1] => 7 - frozenset("ab") | frozenset("bc") => frozenset("abc") - None is None => True - "2" in "python2.7" => True - "def f(): return 2 if 4 < 5 else 3" => "def f(): return 2" * Remove dead code. Examples: - def f(): return 1; return 2 => def f(): return 1 - if DEBUG: print("debug") => pass with DEBUG declared as False - while 0: ... => pass --- Unsafe optimizations are disabled by default. Optimizations can be enabled using a Config class with "features" like "builtin_funcs" (builtin functions like len()) or "pythonbin" (optimized code will be execute by the same Python binary executable). astoptimizer.patch_compile() can be used to hook the optimizer in the compile() builtin function. On Python 3.3, it is enough to use the optimizer on imports (thanks to the importlib). On older versions, the compileall module can be used to compile a whole project using the optimizer. I didn't start to benchmark anything yet, I focused on fixing bugs (not generating invalid code). I will start benchmarks when the "variables" feature (ex: "x=1; print(x)" => "x=1; print(1)") will work. There is an experimental support of variables, but it is still too agressive and generate invalid code in some cases (see the TODO file). I plan to implement other optimizations like unrolling loop or convert a loop to a list comprehension, see the TODO file. Don't hesitate to propose more optimizations if you have some ideas ;-) Victor _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
