See PEP 539 for details.
Highlights of changes:
- Add Thread Specific Storage (TSS) API
- Document the Thread Local Storage (TLS) API as deprecated
- Update code that used TLS API to use TSS API
The concrete PyDict_* API is used to interact with PyInterpreterState.modules in a number of places. This isn't compatible with all dict subclasses, nor with other Mapping implementations. This patch switches the concrete API usage to the corresponding abstract API calls.
We also add a PyImport_GetModule() function (and some other helpers) to reduce a bunch of code duplication.
* Add Py_UNREACHABLE() as an alias to abort().
* Use Py_UNREACHABLE() instead of assert(0)
* Convert more unreachable code to use Py_UNREACHABLE()
* Document Py_UNREACHABLE() and a few other macros.
A bunch of code currently uses PyInterpreterState.modules directly instead of PyImport_GetModuleDict(). This complicates efforts to make changes relative to sys.modules. This patch switches to using PyImport_GetModuleDict() uniformly. Also, a number of related uses of sys.modules are updated for uniformity for the same reason.
Note that this code was already reviewed and merged as part of #1638. I reverted that and am now splitting it up into more focused parts.
PR #1638, for bpo-28411, causes problems in some (very) edge cases. Until that gets sorted out, we're reverting the merge. PR #3506, a fix on top of #1638, is also getting reverted.
* Drop warnoptions from PyInterpreterState.
* Drop xoptions from PyInterpreterState.
* Don't set warnoptions and _xoptions again.
* Decref after adding to sys.__dict__.
* Drop an unused macro.
* Check sys.xoptions *before* we delete it.
* group the (stateful) runtime globals into various topical structs
* consolidate the topical structs under a single top-level _PyRuntimeState struct
* add a check-c-globals.py script that helps identify runtime globals
Other globals are excluded (see globals.txt and check-c-globals.py).
f_trace_lines: enable/disable line trace events
f_trace_opcodes: enable/disable opcode trace events
These are intended primarily for testing of the interpreter
itself, as they make it much easier to emulate signals
arriving at unfortunate times.
* group the (stateful) runtime globals into various topical structs
* consolidate the topical structs under a single top-level _PyRuntimeState struct
* add a check-c-globals.py script that helps identify runtime globals
Other globals are excluded (see globals.txt and check-c-globals.py).
* bpo-9566: Silence warnings from pyatomic.h macros
Apparently MSVC is too stupid to understand that the alternate branch is
not taken and emits a warning for it.
Warnings added in https://github.com/python/cpython/pull/2383
* bpo-9566: A better fix for the pyatomic.h warning
* bpo-9566: Remove a slash
_Py_atomic_* are currently not implemented as atomic operations
when building with MSVC. This patch attempts to implement parts
of the functionality required.
* Improve signal delivery
Avoid using Py_AddPendingCall from signal handler, to avoid calling signal-unsafe functions.
* Remove unused function
* Improve comments
* Add stress test
* Adapt for --without-threads
* Add second stress test
* Add NEWS blurb
* Address comments @haypo
Based on patch by Victor Stinner.
Add private C API function _PyUnicode_AsUnicode() which is similar to
PyUnicode_AsUnicode(), but checks for null characters.
* Make PyTraceMalloc_Track() and PyTraceMalloc_Untrack() functions
public (remove the "_" prefix)
* Remove the _PyTraceMalloc_domain_t type: use directly unsigned
int.
* Document methods
Note: methods are already tested in test_tracemalloc.
* add test to check if were modifying token
* copy list so import tokenize doesnt have side effects on token
* shorten line
* add tokenize tokens to token.h to get them to show up in token
* move ERRORTOKEN back to its previous location, and fix nitpick
* copy comments from token.h automatically
* fix whitespace and make more pythonic
* change to fix comments from @haypo
* update token.rst and Misc/NEWS
* change wording
* some more wording changes
* bpo-16500: Allow registering at-fork handlers
* Address Serhiy's comments
* Add doc for new C API
* Add doc for new Python-facing function
* Add NEWS entry + doc nit
PEP 432 specifies a number of large changes to interpreter startup code, including exposing a cleaner C-API. The major changes depend on a number of smaller changes. This patch includes all those smaller changes.
Make a non-Py_DEBUG, asserts-enabled build of CPython possible. This means
making sure helper functions are defined when NDEBUG is not defined, not
just when Py_DEBUG is defined.
Also fix a division-by-zero in obmalloc.c that went unnoticed because in Py_DEBUG mode, elsize is never zero.
* bpo-6532: Make the thread id an unsigned integer.
From C API side the type of results of PyThread_start_new_thread() and
PyThread_get_thread_ident(), the id parameter of
PyThreadState_SetAsyncExc(), and the thread_id field of PyThreadState
changed from "long" to "unsigned long".
* Restore a check in thread_get_ident().
* 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.
PyEval_Call* APIs are not documented and they doesn't respect PY_SSIZE_T_CLEAN.
So add comment block which recommends PyObject_Call* APIs to ceval.h.
This commit also changes PyEval_CallMethod and PyEval_CallFunction
implementation same to PyObject_CallMethod and PyObject_CallFunction
to reduce future maintenance cost. Optimization to avoid temporary
tuple are copied too.
PyEval_CallFunction(callable, "i", (int)i) now calls callable(i) instead of
raising TypeError. But accepting this edge case is backward compatible.
sys.version and the platform module python_build(),
python_branch(), and python_revision() functions now use
git information rather than hg when building from a repo.
Based on original patches by Brett Cannon and Steve Dower.
* bpo-29463: Add docstring field to some AST nodes.
ClassDef, ModuleDef, FunctionDef, and AsyncFunctionDef has docstring
field for now. It was first statement of there body.
* fix document. thanks travis!
* doc fixes
* Move all functions to call objects in a new Objects/call.c file.
* Rename fast_function() to _PyFunction_FastCallKeywords().
* Copy null_error() from Objects/abstract.c
* Inline type_error() in call.c to not have to copy it, it was only
called once.
* Export _PyEval_EvalCodeWithName() since it is now called
from call.c.
* Move all functions to call objects in a new Objects/call.c file.
* Rename fast_function() to _PyFunction_FastCallKeywords().
* Copy null_error() from Objects/abstract.c
* Inline type_error() in call.c to not have to copy it, it was only
called once.
* Export _PyEval_EvalCodeWithName() since it is now called
from call.c.
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>
a macro if Py_LIMITED_API is not set or set to the value between 0x03050400
and 0x03060000 (not including) or 0x03060100 or higher. Added functions
PySlice_Unpack() and PySlice_AdjustIndices().
PyArg_VaParse() and PyArg_VaParseTupleAndKeywords() were not available in
limited API. PyArg_ValidateKeywordArguments(), PyArg_UnpackTuple() and
Py_BuildValue() were not available in limited API of version < 3.3 when
PY_SSIZE_T_CLEAN is defined.
PyArg_VaParse() and PyArg_VaParseTupleAndKeywords() were not available in
limited API. PyArg_ValidateKeywordArguments(), PyArg_UnpackTuple() and
Py_BuildValue() were not available in limited API of version < 3.3 when
PY_SSIZE_T_CLEAN is defined.
PyArg_VaParse() and PyArg_VaParseTupleAndKeywords() were not available in
limited API. PyArg_ValidateKeywordArguments(), PyArg_UnpackTuple() and
Py_BuildValue() were not available in limited API of version < 3.3 when
PY_SSIZE_T_CLEAN is defined.
It got messed up when I merged my private 3.5.3 release
changes with new work happening in the 3.5 main branch.
(3.5 main branch was in "3.5.3rc1", my branch was "3.5.3+",
and Mercurial helpfully merged the two in a kind of nonsense way.)
Issue #29259, #29263. methoddescr_call() creates a PyCFunction object, call it
and the destroy it. Add a new _PyMethodDef_RawFastCallDict() method to avoid
the temporary PyCFunction object.
Issue #29234: Inlining _PyStack_AsTuple() into callers increases their stack
consumption, Disable inlining to optimize the stack consumption.
Add _Py_NO_INLINE: use __attribute__((noinline)) of GCC and Clang.
It reduces the stack consumption, bytes per call, before => after:
test_python_call: 1040 => 976 (-64 B)
test_python_getitem: 976 => 912 (-64 B)
test_python_iterator: 1120 => 1056 (-64 B)
=> total: 3136 => 2944 (- 192 B)
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.
Special thanks to INADA Naoki for pushing the patch through
the last mile, Serhiy Storchaka for reviewing the code, and to
Victor Stinner for suggesting the idea (originally implemented
in the PyPy project).
Issue #28838: Rename parameters of the "calls" functions of the Python C API.
* Rename 'callable_object' and 'func' to 'callable': any Python callable object
is accepted, not only Python functions
* Rename 'method' and 'nameid' to 'name' (method name)
* Rename 'o' to 'obj'
* Move, fix and update documentation of PyObject_CallXXX() functions
in abstract.h
* Update also the documentaton of the C API (update parameter names)
Replace
_PyObject_CallArg1(func, arg)
with
PyObject_CallFunctionObjArgs(func, arg, NULL)
Using the _PyObject_CallArg1() macro increases the usage of the C stack, which
was unexpected and unwanted. PyObject_CallFunctionObjArgs() doesn't have this
issue.
* Callable object: callable, o, callable_object => func
* Object for method calls: o => obj
* Method name: name or nameid => method
Cleanup also the C code:
* Don't initialize variables to NULL if they are not used before their first
assignement
* Add braces for readability
Issue #28799:
* Remove the PyEval_GetCallStats() function.
* Deprecate the untested and undocumented sys.callstats() function.
* Remove the CALL_PROFILE special build
Use the sys.setprofile() function, cProfile or profile module to profile
function calls.
When Python is not compiled with PGO, the performance of Python on call_simple
and call_method microbenchmarks depend highly on the code placement. In the
worst case, the performance slowdown can be up to 70%.
The GCC __attribute__((hot)) attribute helps to keep hot code close to reduce
the risk of such major slowdown. This attribute is ignored when Python is
compiled with PGO.
The following functions are considered as hot according to statistics collected
by perf record/perf report:
* _PyEval_EvalFrameDefault()
* call_function()
* _PyFunction_FastCall()
* PyFrame_New()
* frame_dealloc()
* PyErr_Occurred()
new exception with setting current exception as __cause__.
_PyErr_FormatFromCause(exception, format, args...) is equivalent to Python
raise exception(format % args) from sys.exc_info()[1]
new exception with setting current exception as __cause__.
_PyErr_FormatFromCause(exception, format, args...) is equivalent to Python
raise exception(format % args) from sys.exc_info()[1]
Masayuki Yamamoto
Yury Selivanov
Jelle Zijlstra
Christian Heimes
Benjamin Peterson
Ned Deily
Serhiy Storchaka
Eric Snow
Barry Warsaw
Nick Coghlan
Steve Dower
Antoine Pitrou
Segev Finer
Pär Björklund
Ville Skyttä
Dino Viehland
Victor Stinner
Albert-Jan Nijburg
Xiang Zhang
T. Wouters
Niklas Fiekas
INADA Naoki
n.d. parker
Joseph Shen
INADA Naoki
Larry Hastings
Antoine Pitrou
Raymond Hettinger
Eric V. Smith
Alexander Belopolsky