In python on x86-64, are the first 6 arguments typically passed on registers? Question: To the best of my knowledge, in low level languages such as C, it is generally advisable to keep the number of arguments to functions to 6 or lower, since then there is no need to pass arguments on the stack …
Java ByteBuffer similar function in Python Question: I need to reimplement following function which converts 8 digit List to 32 digit List via ByteBuffer to python. So it can be used a python pipeline. As a data scientist, I have been scratching my head how to do it right. I assume I can try to …
How do I disassemble a Python script from the command line? Question: With gcc you can use -S to stop compilation after your code has been compiled into assembly. Is there a similar feature with Python/bytecode? I know of ways like: import dis x = compile(‘print(1)’, ”, ‘eval’) dis.dis(x) Which prints: 1 0 LOAD_NAME 0 …
Can someone explain CALL_FUNCTION and RETURN_VALUE from python bytecode Question: I’m trying to understand python bytecode and I’m caught on CALL_FUNCTION and RETURN_VALUE. Does a function have its own stack? If not, what does the documentation mean by "Returns TOS to the caller of the function"? Asked By: Jam || Source Answers: In CPython every …
How to read python bytecode? Question: I am having a lot of difficulty understanding Python’s bytecode and its dis module. import dis def func(): x = 1 dis.dis(func) The above code when typed in the interpreter produces the following output: 0 LOAD_CONST 1(1) 3 STORE_FAST 0(x) 6 LOAD_CONST 0(NONE) 9 RETURN_VALUE E.g.: What is the …
Why doesn't Python evaluate constant number arithmetic before compiling to bytecode? Question: In the following code, why doesn’t Python compile f2 to the same bytecode as f1? Is there a reason not to? >>> def f1(x): x*100 >>> dis.dis(f1) 2 0 LOAD_FAST 0 (x) 3 LOAD_CONST 1 (100) 6 BINARY_MULTIPLY 7 POP_TOP 8 LOAD_CONST 0 …
Generate .pyc from Python AST? Question: How would I generate a .pyc file from a Python AST such that I could import the file from Python? I’ve used compile to create a code object, then written the co_code attribute to a file, but when I try to import the file from Python, I get an …
`goto` in Python Question: I must use goto in Python. I found entrians goto but my Python implementation (CPython 2.7.1 on Mac) does not have this module, so it doesn’t seem to be portable. It should at least work in all Python implementations which support CPython bytecode (esp. I care about CPython and PyPy). Then …
What is the use of Python's basic optimizations mode? (python -O) Question: Python has a flag -O that you can execute the interpreter with. The option will generate “optimized” bytecode (written to .pyo files), and given twice, it will discard docstrings. From Python’s man page: -O Turn on basic optimizations. This changes the filename extension …
How can I strip Python logging calls without commenting them out? Question: Today I was thinking about a Python project I wrote about a year back where I used logging pretty extensively. I remember having to comment out a lot of logging calls in inner-loop-like scenarios (the 90% code) because of the overhead (hotshot indicated …
