This PR sets up tagged pointers for CPython.
The general idea is to create a separate struct _PyStackRef for everything on the evaluation stack to store the bits. This forces the C compiler to warn us if we try to cast things or pull things out of the struct directly.
Only for free threading: We tag the low bit if something is deferred - that means we skip incref and decref operations on it. This behavior may change in the future if Mark's plans to defer all objects in the interpreter loop pans out.
This implies a strict stack reference discipline is required. ALL incref and decref operations on stackrefs must use the stackref variants. It is unsafe to untag something then do normal incref/decref ops on it.
The new incref and decref variants are called dup and close. They mimic a "handle" API operating on these stackrefs.
Please read Include/internal/pycore_stackref.h for more information!
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Co-authored-by: Mark Shannon <9448417+markshannon@users.noreply.github.com>
This makes the following macros public as part of the non-limited C-API for
locking a single object or two objects at once.
* `Py_BEGIN_CRITICAL_SECTION(op)` / `Py_END_CRITICAL_SECTION()`
* `Py_BEGIN_CRITICAL_SECTION2(a, b)` / `Py_END_CRITICAL_SECTION2()`
The supporting functions and structs used by the macros are also exposed for
cases where C macros are not available.
Structure layout, and especially bitfields, sometimes resulted in clearly
wrong behaviour like overlapping fields. This fixes
Co-authored-by: Gregory P. Smith <gps@python.org>
Co-authored-by: Petr Viktorin <encukou@gmail.com>
Add missing import to code that handles too large files and offsets.
Use list, not tuple, for a mutable sequence.
Add tests to prevent similar mistakes.
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Co-authored-by: Gregory P. Smith [Google LLC] <greg@krypto.org>
Co-authored-by: Kirill Podoprigora <kirill.bast9@mail.ru>
Add tests for "import", pkgutil.resolve_name() and unittest.mock.path()
for cases when "import a.b as x" and "from a import b as x" give
different results.
Makes sys.settrace, sys.setprofile, and monitoring generally thread-safe.
Mostly uses a stop-the-world approach and synchronization around the code object's _co_instrumentation_version. There may be a little bit of extra synchronization around the monitoring data that's required to be TSAN clean.
Introduce a unified 16-bit backoff counter type (``_Py_BackoffCounter``),
shared between the Tier 1 adaptive specializer and the Tier 2 optimizer. The
API used for adaptive specialization counters is changed but the behavior is
(supposed to be) identical.
The behavior of the Tier 2 counters is changed:
- There are no longer dynamic thresholds (we never varied these).
- All counters now use the same exponential backoff.
- The counter for ``JUMP_BACKWARD`` starts counting down from 16.
- The ``temperature`` in side exits starts counting down from 64.
These helpers make it easier to customize and inspect the config used to initialize interpreters. This is especially valuable in our tests. I found inspiration from the PyConfig API for the PyInterpreterConfig dict conversion stuff. As part of this PR I've also added a bunch of tests.
Co-authored-by: Hugo van Kemenade <1324225+hugovk@users.noreply.github.com>
Co-authored-by: Malcolm Smith <smith@chaquo.com>
Co-authored-by: Ned Deily <nad@python.org>
I added it quite a while ago as a strategy for managing interpreter lifetimes relative to the PEP 554 (now 734) implementation. Relatively recently I refactored that implementation to no longer rely on InterpreterID objects. Thus now I'm removing it.
* Ensure importlib.metadata tests do not leak references in sys.modules.
* Move importlib.metadata tests to their own package for easier syncing with importlib_metadata.
* Update owners and makefile for new directories.
* Add blurb
* Split long.c tests of _testcapi into two parts: limited C API tests
in _testlimitedcapi and non-limited C API tests in _testcapi.
* Move testcapi_long.h from Modules/_testcapi/ to
Modules/_testlimitedcapi/.
* Add MODULE__TESTLIMITEDCAPI_DEPS to Makefile.pre.in.
Keep Tools/build/deepfreeze.py around (we may repurpose it for deepfreezing non-code objects),
and keep basic "clean" targets that remove the output of former deep-freeze activities,
to keep the build directories of current devs clean.
Co-authored-by: Erlend E. Aasland <erlend@python.org>
Co-authored-by: Hugo van Kemenade <1324225+hugovk@users.noreply.github.com>
Co-authored-by: Victor Stinner <vstinner@python.org>
If awailable, enable -fstrict-overflow for libmpdec. Also
shut off false positive warnings (-Warray-bounds).
The later was backported from mpdecimal-4.0.0.
This change is part of the work on PEP-738: Adding Android as a
supported platform.
* Remove the "1.0" suffix from libpython's filename on Android, which
would prevent Gradle from packaging it into an app.
* Simplify the build command in the Makefile so that libpython always
gets given an SONAME with the `-Wl-h` argument, even if the SONAME is
identical to the actual filename.
* Disable a number of functions on Android which can be compiled and
linked against, but always fail at runtime. As a result, the native
_multiprocessing module is no longer built for Android.
* gh-115390 (bee7bb331) added some pre-determined results to the
configure script for things that can't be autodetected when
cross-compiling; this change adds Android to these where appropriate.
* Add a couple more pre-determined results for Android, and making them
cover iOS as well. This means the --enable-ipv6 configure option will
no longer be required on either platform.
Part of the work on PEP 738: Adding Android as a supported platform.
* Rename the LIBPYTHON variable to MODULE_LDFLAGS, to more accurately
reflect its purpose.
* Edit makesetup to use MODULE_LDFLAGS when linking extension modules.
* Edit the Makefile so that extension modules depend on libpython on
Android and Cygwin.
* Restore `-fPIC` on Android. It was removed several years ago with a
note that the toolchain used it automatically, but this is no longer
the case. Omitting it causes all linker commands to fail with an error
like `relocation R_AARCH64_ADR_PREL_PG_HI21 cannot be used against
symbol '_Py_FalseStruct'; recompile with -fPIC`.
This adds a safe memory reclamation scheme based on FreeBSD's "GUS" and
quiescent state based reclamation (QSBR). The API provides a mechanism
for callers to detect when it is safe to free memory that may be
concurrently accessed by readers.
Victor Stinner
Sergey B Kirpichev
Russell Keith-Magee
Irit Katriel
Ken Jin
Sam Gross
Jason R. Coombs
Matthias Görgens
Erlend E. Aasland
Eugene Triguba
John Sirois
Pablo Galindo Salgado
Serhiy Storchaka
Eric Snow
Yichen Yan
Dino Viehland
Guido van Rossum
Skip Montanaro
Malcolm Smith
Mark Shannon
Seth Michael Larson