Return -1 and set an exception on error; return 0 if the iterator is
exhausted, and return 1 if the next item was fetched successfully.
Prefer this API to PyIter_Next(), which requires the caller to use
PyErr_Occurred() to differentiate between iterator exhaustion and errors.
Co-authered-by: Irit Katriel <iritkatriel@yahoo.com>
* Convert PyObject_DelAttr() and PyObject_DelAttrString() macros to
functions.
* Add PyObject_DelAttr() and PyObject_DelAttrString() functions to
the stable ABI.
* Replace PyObject_SetAttr(obj, name, NULL) with
PyObject_DelAttr(obj, name).
Fix PyAiter_Check to only check for the `__anext__` presense (not for
`__aiter__`). Rename `PyAiter_Check()` to `PyAIter_Check()`,
`PyObject_GetAiter()` -> `PyObject_GetAIter()`.
Co-authored-by: Pablo Galindo Salgado <Pablogsal@gmail.com>
Add a new public PyObject_CallNoArgs() function to the C API: call a
callable Python object without any arguments.
It is the most efficient way to call a callback without any argument.
On x86-64, for example, PyObject_CallFunctionObjArgs(func, NULL)
allocates 960 bytes on the stack per call, whereas
PyObject_CallNoArgs(func) only allocates 624 bytes per call.
It is excluded from stable ABI 3.8.
Replace private _PyObject_CallNoArg() with public
PyObject_CallNoArgs() in C extensions: _asyncio, _datetime,
_elementtree, _pickle, _tkinter and readline.
During development of the limited API support for PySide,
we saw an error in a macro that accessed a type field.
This patch fixes the 7 errors in the Python headers.
Macros which were not written as capitals were implemented
as function.
To do the necessary analysis again, a script was included that
parses all headers and looks for "->tp_" in serctions which can
be reached with active limited API.
It is easily possible to call this script as a test.
Error listing:
../../Include/objimpl.h:243
#define PyObject_IS_GC(o) (PyType_IS_GC(Py_TYPE(o)) && \
(Py_TYPE(o)->tp_is_gc == NULL || Py_TYPE(o)->tp_is_gc(o)))
Action: commented only
../../Include/objimpl.h:362
#define PyType_SUPPORTS_WEAKREFS(t) ((t)->tp_weaklistoffset > 0)
Action: commented only
../../Include/objimpl.h:364
#define PyObject_GET_WEAKREFS_LISTPTR(o) \
((PyObject **) (((char *) (o)) + Py_TYPE(o)->tp_weaklistoffset))
Action: commented only
../../Include/pyerrors.h:143
#define PyExceptionClass_Name(x) \
((char *)(((PyTypeObject*)(x))->tp_name))
Action: implemented function
../../Include/abstract.h:593
#define PyIter_Check(obj) \
((obj)->ob_type->tp_iternext != NULL && \
(obj)->ob_type->tp_iternext != &_PyObject_NextNotImplemented)
Action: implemented function
../../Include/abstract.h:713
#define PyIndex_Check(obj) \
((obj)->ob_type->tp_as_number != NULL && \
(obj)->ob_type->tp_as_number->nb_index != NULL)
Action: implemented function
../../Include/abstract.h:924
#define PySequence_ITEM(o, i)\
( Py_TYPE(o)->tp_as_sequence->sq_item(o, i) )
Action: commented only
* Add _PyObject_HasFastCall()
* partial_call() now avoids temporary tuple to pass positional
arguments if the callable supports the FASTCALL calling convention
for positional arguments.
* Fix also a performance regression in partial_call() if the callable
doesn't support FASTCALL.
Issue #29507: Optimize slots calling Python methods. For Python methods, get
the unbound Python function and prepend arguments with self, rather than
calling the descriptor which creates a temporary PyMethodObject.
Add a new _PyObject_FastCall_Prepend() function used to call the unbound Python
method with self. It avoids the creation of a temporary tuple to pass
positional arguments.
Avoiding temporary PyMethodObject and avoiding temporary tuple makes Python
slots up to 1.46x faster. Microbenchmark on a __getitem__() method implemented
in Python:
Median +- std dev: 121 ns +- 5 ns -> 82.8 ns +- 1.0 ns: 1.46x faster (-31%)
Co-Authored-by: INADA Naoki <songofacandy@gmail.com>
Issue #29233: Replace the inefficient _PyObject_VaCallFunctionObjArgs() with
_PyObject_FastCall() in call_method() and call_maybe().
Only a few functions call call_method() and call it with a fixed number of
arguments. Avoid the complex and expensive _PyObject_VaCallFunctionObjArgs()
function, replace it with an array allocated on the stack with the exact number
of argumlents.
It reduces the stack consumption, bytes per call, before => after:
test_python_call: 1168 => 1152 (-16 B)
test_python_getitem: 1344 => 1008 (-336 B)
test_python_iterator: 1568 => 1232 (-336 B)
Remove the _PyObject_VaCallFunctionObjArgs() function which became useless.
Rename it to object_vacall() and make it private.
Issue #28838: The documentation is of the Python C API is more complete and
more up to date than this old comment.
Removal suggested by Antoine Pitrou.
Issue #28870: Add a new _PY_FASTCALL_SMALL_STACK constant, size of "small
stacks" allocated on the C stack to pass positional arguments to
_PyObject_FastCall().
_PyObject_Call_Prepend() now uses a small stack of 5 arguments (40 bytes)
instead of 8 (64 bytes), since it is modified to use _PY_FASTCALL_SMALL_STACK.
Rewrite all comments to use the same style than other Python header files:
comment functions *before* their declaration, no newline between the comment
and the declaration.
Reformat some comments, add newlines, to make them easier to read.
Quote argument like 'arg' to mention an argument in a comment.
Erlend E. Aasland
Pieter Eendebak
Serhiy Storchaka
Victor Stinner
Inada Naoki
Wenzel Jakob
Petr Viktorin
Will Hawkins
Christian Clauss
Yury Selivanov
Joshua Bronson
Erlend Egeberg Aasland
Vladimir Matveev
Min ho Kim
Victor Stinner
Zackery Spytz
Christian Tismer
Andrew Svetlov
Ville Skyttä
Victor Stinner