GH-14039: allow (no more than) one wholly empty arena on the usable_arenas list.
This prevents thrashing in some easily-provoked simple cases that could end up creating and destroying an arena on each loop iteration in client code. Intuitively, if the only arena on the list becomes empty, it makes scant sense to give it back to the system unless we know we'll never need another free pool again before another arena frees a pool. If the latter obtains, then - yes - this will "waste" an arena.
When inheriting a heap subclass from a vectorcall class that sets
`.tp_call=PyVectorcall_Call` (as recommended in PEP 590), the subclass does
not inherit `_Py_TPFLAGS_HAVE_VECTORCALL`, and thus `PyVectorcall_Call` does
not work for it.
This attempts to solve the issue by:
* always inheriting `tp_vectorcall_offset` unless `tp_call` is overridden
in the subclass
* inheriting _Py_TPFLAGS_HAVE_VECTORCALL for static types, unless `tp_call`
is overridden
* making `PyVectorcall_Call` ignore `_Py_TPFLAGS_HAVE_VECTORCALL`
This means it'll be ever more important to only call `PyVectorcall_Call`
on classes that support vectorcall. In `PyVectorcall_Call`'s intended role
as `tp_call` filler, that's not a problem.
This adds a vector of "search fingers" so that usable_arenas can be kept in sorted order (by number of free pools) via constant-time operations instead of linear search.
This should reduce worst-case time for reclaiming a great many objects from O(A**2) to O(A), where A is the number of arenas. See bpo-37029.
It is now allowed to add new fields at the end of the PyTypeObject struct without having to allocate a dedicated compatibility flag in tp_flags.
This will reduce the risk of running out of bits in the 32-bit tp_flags value.
* bpo-22385: Support output separators in hex methods.
Also in binascii.hexlify aka b2a_hex.
The underlying implementation behind all hex generation in CPython uses the
same pystrhex.c implementation. This adds support to bytes, bytearray,
and memoryview objects.
The binascii module functions exist rather than being slated for deprecation
because they return bytes rather than requiring an intermediate step through a
str object.
This change was inspired by MicroPython which supports sep in its binascii
implementation (and does not yet support the .hex methods).
https://bugs.python.org/issue22385
* No type cache for types with specialized mro, invalidation is hard.
* FIX: Don't disable method cache custom types that do not implement mro().
* fixing implem.
* Avoid storing error flags, also decref.
* news entry
* Clear as soon as we're getting an error.
* FIX: Reference leak.
Update PyObject_CallMethodObjArgs and _PyObject_CallMethodIdObjArgs
to use _PyObject_GetMethod to avoid creating a bound method object
in many cases.
On a microbenchmark of PyObject_CallMethodObjArgs calling a method on
an interpreted Python class, this optimization resulted in a 1.7x
speedup.
…nctions with asserts
The actual overflow can never happen because of the following:
* The size of a list can't be greater than PY_SSIZE_T_MAX / sizeof(PyObject*).
* The size of a pointer on all supported plaftorms is at least 4 bytes.
* ofs is positive and less than the list size at the beginning of each iteration.
https://bugs.python.org/issue35091
* Add _PyInitError functions:
* _PyInitError_Ok()
* _PyInitError_Error()
* _PyInitError_NoMemory()
* _PyInitError_Exit()
* _PyInitError_IsError()
* _PyInitError_IsExit()
* _PyInitError_Failed()
* frozenmain.c and _testembed.c now use functions rather than macros.
* Move _Py_INIT_xxx() macros to the internal API.
* Move _PyWstrList_INIT macro to the internal API.
* Add PyMemAllocatorName enum
* _PyPreConfig.allocator type becomes PyMemAllocatorName, instead of
char*
* Remove _PyPreConfig_Clear()
* Add _PyMem_GetAllocatorName()
* Rename _PyMem_GetAllocatorsName() to
_PyMem_GetCurrentAllocatorName()
* Remove _PyPreConfig_SetAllocator(): just call
_PyMem_SetupAllocators() directly, we don't have do reallocate the
configuration with the new allocator anymore!
* _PyPreConfig_Write() parameter becomes const, as it should be in
the first place!
The final addition (cur += step) may overflow, so use size_t for "cur".
"cur" is always positive (even for negative steps), so it is safe to use
size_t here.
Co-Authored-By: Martin Panter <vadmium+py@gmail.com>
Add new trashcan macros to deal with a double deallocation that could occur when the `tp_dealloc` of a subclass calls the `tp_dealloc` of a base class and that base class uses the trashcan mechanism.
Patch by Jeroen Demeyer.
_PyCoreConfig: Change filesystem_encoding, filesystem_errors,
stdio_encoding and stdio_errors fields type from char* to wchar_t*.
Changes:
* PyInterpreterState: replace fscodec_initialized (int) with fs_codec
structure.
* Add get_error_handler_wide() and unicode_encode_utf8() helper
functions.
* Add error_handler parameter to unicode_encode_locale()
and unicode_decode_locale().
* Remove _PyCoreConfig_SetString().
* Rename _PyCoreConfig_SetWideString() to _PyCoreConfig_SetString().
* Rename _PyCoreConfig_SetWideStringFromString()
to _PyCoreConfig_DecodeLocale().
Add _Py_FORCE_UTF8_LOCALE and _Py_FORCE_UTF8_FS_ENCODING macros to
avoid factorize "#if defined(__ANDROID__) || defined(__VXWORKS__)"
and "#if defined(__APPLE__)".
Cleanup also config_init_fs_encoding().
This commit contains the implementation of PEP570: Python positional-only parameters.
* Update Grammar/Grammar with new typedarglist and varargslist
* Regenerate grammar files
* Update and regenerate AST related files
* Update code object
* Update marshal.c
* Update compiler and symtable
* Regenerate importlib files
* Update callable objects
* Implement positional-only args logic in ceval.c
* Regenerate frozen data
* Update standard library to account for positional-only args
* Add test file for positional-only args
* Update other test files to account for positional-only args
* Add News entry
* Update inspect module and related tests
Omit serialno field from debug hooks on Python memory allocators to
reduce the memory footprint by 5%.
Enable tracemalloc to get the traceback where a memory block has been
allocated when a fatal memory error is logged to decide where to put
a breakpoint.
Compile Python with PYMEM_DEBUG_SERIALNO defined to get back the
field.
Add a new _PyObject_CheckConsistency() function which can be used to
help debugging. The function is available in release mode.
Add a 'check_content' parameter to _PyDict_CheckConsistency().
Modify CLEANBYTE, DEADDYTE and FORBIDDENBYTE constants: use 0xCD,
0xDD and 0xFD, rather than 0xCB, 0xBB and 0xFB, to use the same byte
patterns than Windows CRT debug malloc() and free().
Replace _PyMem_IsFreed() function with _PyMem_IsPtrFreed() inline
function. The function is now way more efficient, it became a simple
comparison on integers, rather than a short loop. It detects also
uninitialized bytes and "forbidden bytes" filled by debug hooks
on memory allocators.
Add unit tests on _PyObject_IsFreed().
No longer limit repr(structseq) to 512 bytes. Use _PyUnicodeWriter
for better performance and to write directly Unicode rather than
encoding repr() value to UTF-8 and then decoding from UTF-8.
When Python is compiled with Valgrind support, release Unicode
interned strings at exit in _PyUnicode_Fini().
* Rename _Py_ReleaseInternedUnicodeStrings() to
unicode_release_interned() and make it private.
* unicode_release_interned() is now called from _PyUnicode_Fini():
it must be called with a running Python thread state for TRASHCAN,
it cannot be called from pymain_free().
* Don't display statistics on interned strings at exit anymore
Python initialization now fails if decoding pybuilddir.txt
configuration file fails at startup.
_PyPathConfig_Calculate() now reports memory allocation failure and
decoding error on decoding pybuilddir.txt content from
UTF-8/surrogateescape.
Jeroen Demeyer
Hai Shi
Tim Peters
Paul Monson
Victor Stinner
Raymond Hettinger
Zackery Spytz
Inada Naoki
Petr Viktorin
Pablo Galindo
Mark Dickinson
Serhiy Storchaka
Francisco Couzo
Tim Hoffmann
Antoine Pitrou
Gregory P. Smith
Julien Palard
Michael J. Sullivan
Cheryl Sabella
Steve Dower
Alexey Izbyshev
David Carlier
Emmanuel Arias
Benjamin Peterson
penguindustin
Eddie Elizondo
Srinivas Reddy Thatiparthy (శ్రీనివాస్ రెడ్డి తాటిపర్తి)
Mark Dickinson
Kingsley M
Thomas Perl
Max Bernstein
Eddie Elizondo
Rémi Lapeyre
stratakis
Eric Snow