[Python-Dev] PyObject_CallFunction(func, "O", arg) special case

[Serhiy Storchaka]

On 09.12.16 19:46, Victor Stinner wrote:
> Last days, I patched functions of PyObject_CallFunction() family to
> use internally fast calls. I implemented the special case to keep
> backward compatibility.
>
> I replaced a lot of code using PyObject_CallFunction() with
> PyObject_CallFunctionObjArgs() when the format string was only made of
> "O", PyObject* arguments. I made this change to optimize the code, but
> indirectly, it avoids also the special case for code which used
> exactly "O" format. See:
> http://bugs.python.org/issue28915

I didn't have a change to make a review of your patches, because they 
were pushed 7 minutes after publishing a patch. I'm still in the process 
of post-commit reviewing. Could you please give more time for pre-commit 
review?

I thought about similar changes, but since I didn't have evidences that 
they cause performance gain, I dropped my patches. Do you have benchmark 
results that proof the speed up for all your changes?

Did you checked that your changes do not increase C stack consumption?