It now supports a "full" fallback to _PyFunction_GetXIData() and then `_PyPickle_GetXIData()`. There's also room for other fallback modes if that later makes sense.
This converts functions, code, str, bytes, bytearray, and memoryview objects to PyCodeObject,
and ensure that the object looks like a script. That means no args, no return, and no closure.
_PyCode_GetPureScriptXIData() takes it a step further and ensures there are no globals.
We also add _PyObject_SupportedAsScript() to the internal C-API.
This reverts commit 3c73cf5 (gh-133497), which itself reverted
the original commit d270bb5 (gh-133221).
We reverted the original change due to failing android tests.
The checks in _PyCode_CheckNoInternalState() were too strict,
so we've relaxed them.
"Stateless" code is a function or code object which does not rely on external state or internal state.
It may rely on arguments and builtins, but not globals or a closure. I've left a comment in
pycore_code.h that provides more detail.
We also add _PyFunction_VerifyStateless(). The new functions will be used in several later changes
that facilitate "sharing" functions and code objects between interpreters.
This reverts commit 811edcf (gh-133232), which itself reverted the original commit 811edcf (gh-133128).
We reverted the original change due to failing s390 builds (a big-endian architecture).
It ended up that I had not accommodated op caches.
There's some extra complexity due to making sure we we get things right when handling functions and classes defined in the __main__ module. This is also reflected in the tests, including the addition of extra functions in test.support.import_helper.
This helper is useful in a variety of ways, including in demonstrating how the different counts relate to one another.
It will be used in a later change to help identify if a function is "stateless", meaning it doesn't have any free vars or globals.
Note that a majority of this change is tests.
The function indicates whether or not the function has a return statement.
This is used by a later change related treating some functions like scripts.
The `test_load_global_module()` test consumes a lot of dict key versions.
Skip the test if we have consumed half of the available versions that can be
used for the "load global" cache.
The following are added to the internal C-API:
* _PyErr_FormatV()
* _PyErr_SetModuleNotFoundError()
* _PyXIData_GetNotShareableErrorType()
* _PyXIData_FormatNotShareableError()
We also drop _PyXIData_lookup_context_t and _PyXIData_GetLookupContext().
The `free_work_item()` function in QSBR may call arbitrary code via
Python object destructors, which may reenter the QSBR code. Reorder
the processing of work items to be robust to reentrancy.
Also fix the TODO for the out of memory situation.
* Implement C recursion protection with limit pointers for Linux, MacOS and Windows
* Remove calls to PyOS_CheckStack
* Add stack protection to parser
* Make tests more robust to low stacks
* Improve error messages for stack overflow
Revert "GH-91079: Implement C stack limits using addresses, not counters. (GH-130007)" for now
Unfortunatlely, the change broke some buildbots.
This reverts commit 2498c22fa0.
* Implement C recursion protection with limit pointers
* Remove calls to PyOS_CheckStack
* Add stack protection to parser
* Make tests more robust to low stacks
* Improve error messages for stack overflow
Remove _PyInterpreterState_GetConfigCopy() and
_PyInterpreterState_SetConfig() private functions. PEP 741 "Python
Configuration C API" added a better public C API: PyConfig_Get() and
PyConfig_Set().
* Add `_PyDictKeys_StringLookupSplit` which does locking on dict keys and
use in place of `_PyDictKeys_StringLookup`.
* Change `_PyObject_TryGetInstanceAttribute` to use that function
in the case of split keys.
* Add `unicodekeys_lookup_split` helper which allows code sharing
between `_Py_dict_lookup` and `_PyDictKeys_StringLookupSplit`.
* Fix locking for `STORE_ATTR_INSTANCE_VALUE`. Create
`_GUARD_TYPE_VERSION_AND_LOCK` uop so that object stays locked and
`tp_version_tag` cannot change.
* Pass `tp_version_tag` to `specialize_dict_access()`, ensuring
the version we store on the cache is the correct one (in case of
it changing during the specalize analysis).
* Split `analyze_descriptor` into `analyze_descriptor_load` and
`analyze_descriptor_store` since those don't share much logic.
Add `descriptor_is_class` helper function.
* In `specialize_dict_access`, double check `_PyObject_GetManagedDict()`
in case we race and dict was materialized before the lock.
* Avoid borrowed references in `_Py_Specialize_StoreAttr()`.
* Use `specialize()` and `unspecialize()` helpers.
* Add unit tests to ensure specializing happens as expected in FT builds.
* Add unit tests to attempt to trigger data races (useful for running under TSAN).
* Add `has_split_table` function to `_testinternalcapi`.
* Mark almost all reachable objects before doing collection phase
* Add stats for objects marked
* Visit new frames before each increment
* Update docs
* Clearer calculation of work to do.
* Mark almost all reachable objects before doing collection phase
* Add stats for objects marked
* Visit new frames before each increment
* Remove lazy dict tracking
* Update docs
* Clearer calculation of work to do.
These changes makes it easier to backport the _interpreters, _interpqueues, and _interpchannels modules to Python 3.12.
This involves the following:
* add the _PyXI_GET_STATE() and _PyXI_GET_GLOBAL_STATE() macros
* add _PyXIData_lookup_context_t and _PyXIData_GetLookupContext()
* add _Py_xi_state_init() and _Py_xi_state_fini()
The primary objective here is to allow some later changes to be cleaner. Mostly this involves renaming things and moving a few things around.
* CrossInterpreterData -> XIData
* crossinterpdatafunc -> xidatafunc
* split out pycore_crossinterp_data_registry.h
* add _PyXIData_lookup_t
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.
* Remove `@suppress_immortalization` decorator
* Make suppression flag per-thread instead of per-interpreter
* Suppress immortalization in `eval()` to avoid refleaks in three tests
(test_datetime.test_roundtrip, test_logging.test_config8_ok, and
test_random.test_after_fork).
* frozenset() is constant, but not a singleton. When run multiple times,
the test could fail due to constant interning.
Use a `_PyStackRef` and defer the reference to `f_funcobj` when
possible. This avoids some reference count contention in the common case
of executing the same code object from multiple threads concurrently in
the free-threaded build.
There were a still a number of gaps in the tests, including not looking
at all the builtin types and not checking wrappers in subinterpreters
that weren't in the main interpreter. This fixes all that.
I considered incorporating the names of the PyTypeObject fields
(a la gh-122866), but figured doing so doesn't add much value.
sobolevn