Each thread specializes a thread-local copy of the bytecode, created on the first RESUME, in free-threaded builds. All copies of the bytecode for a code object are stored in the co_tlbc array on the code object. Threads reserve a globally unique index identifying its copy of the bytecode in all co_tlbc arrays at thread creation and release the index at thread destruction. The first entry in every co_tlbc array always points to the "main" copy of the bytecode that is stored at the end of the code object. This ensures that no bytecode is copied for programs that do not use threads.
Thread-local bytecode can be disabled at runtime by providing either -X tlbc=0 or PYTHON_TLBC=0. Disabling thread-local bytecode also disables specialization.
Concurrent modifications to the bytecode made by the specializing interpreter and instrumentation use atomics, with specialization taking care not to overwrite an instruction that was instrumented concurrently.
In Emscripten and other cross builds, the build file system and the host file
system look different. For instance, we may want to install into
`cross-build/$TARGET/lib`, and then mount that as `/lib` in the host file
system. This change adds a distinction between:
* `prefix` -- the path in the build file system where we want to install the files
* `host_prefix` -- the path in the host file system where getpath.c will look for the files
And similarly for `exec_prefix` and `host_exec_prefix`. At present, this is only
used for Emscripten.
This is essentially a cleanup, moving a handful of API declarations to the header files where they fit best, creating new ones when needed.
We do the following:
* add pycore_debug_offsets.h and move _Py_DebugOffsets, etc. there
* inline struct _getargs_runtime_state and struct _gilstate_runtime_state in _PyRuntimeState
* move struct _reftracer_runtime_state to the existing pycore_object_state.h
* add pycore_audit.h and move to it _Py_AuditHookEntry , _PySys_Audit(), and _PySys_ClearAuditHooks
* add audit.h and cpython/audit.h and move the existing audit-related API there
*move the perfmap/trampoline API from cpython/sysmodule.h to cpython/ceval.h, and remove the now-empty cpython/sysmodule.h
Currently, we only use per-thread reference counting for heap type objects and
the naming reflects that. We will extend it to a few additional types in an
upcoming change to avoid scaling bottlenecks when creating nested functions.
Rename some of the files and functions in preparation for this change.
* Tools/build/stable_abi.py: Improve ergonomics
- Make the manifest file argument optional
- Output resolved paths with --list (getting rid of `../../`)
- Mention --all or --generate-all if no actions are specified
* Don't hardcode Misc/stable_abi.toml in Makefile, rely on the default
* gh-116608: Apply style and compatibility changes from importlib_metadata.
* gh-121735: Ensure module-adjacent resources are loadable from a zipfile.
* gh-121735: Allow all modules to be processed by the ZipReader.
* Add blurb
* Remove update-zips script, unneeded.
* Remove unnecessary references to removed static fixtures.
* Remove zipdata fixtures, unused.
This replaces the existing hashlib Blake2 module with a single implementation that uses HACL\*'s Blake2b/Blake2s implementations. We added support for all the modes exposed by the Python API, including tree hashing, leaf nodes, and so on. We ported and merged all of these changes upstream in HACL\*, added test vectors based on Python's existing implementation, and exposed everything needed for hashlib.
This was joint work done with @R1kM.
See the PR for much discussion and benchmarking details. TL;DR: On many systems, 8-50% faster (!) than `libb2`, on some systems it appeared 10-20% slower than `libb2`.
The free-threaded build partially stores heap type reference counts in
distributed manner in per-thread arrays. This avoids reference count
contention when creating or destroying instances.
Co-authored-by: Ken Jin <kenjin@python.org>
This combines and updates our freelist handling to use a consistent
implementation. Objects in the freelist are linked together using the
first word of memory block.
If configured with freelists disabled, these operations are essentially
no-ops.
Adds a --with-app-store-compliance configuration option that patches out code known to be an issue with App Store review processes. This option is applied automatically on iOS, and optionally on macOS.
On POSIX systems, excluding macOS framework installs, the lib directory
for the free-threaded build now includes a "t" suffix to avoid conflicts
with a co-located default build installation.
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!
---------
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.
---------
Co-authored-by: Gregory P. Smith [Google LLC] <greg@krypto.org>
Co-authored-by: Kirill Podoprigora <kirill.bast9@mail.ru>
mpage
Tomas R.
Erlend E. Aasland
sobolevn
Hood Chatham
Jacob Walls
Eric Snow
Sam Gross
Petr Viktorin
Russell Keith-Magee
Jason R. Coombs
Irit Katriel
algonell
Pablo Galindo Salgado
Malcolm Smith
Jonathan Protzenko
Miro Hrončok
Kirill Podoprigora
Ned Deily
Marc Mueller
Victor Stinner
Sergey B Kirpichev
Ken Jin
Matthias Görgens
Eugene Triguba
John Sirois