mirror of https://github.com/python/cpython
864 lines
27 KiB
C
864 lines
27 KiB
C
#ifndef Py_INTERNAL_OBJECT_H
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#define Py_INTERNAL_OBJECT_H
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#ifdef __cplusplus
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extern "C" {
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#endif
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#ifndef Py_BUILD_CORE
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# error "this header requires Py_BUILD_CORE define"
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#endif
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#include <stdbool.h>
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#include "pycore_gc.h" // _PyObject_GC_IS_TRACKED()
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#include "pycore_emscripten_trampoline.h" // _PyCFunction_TrampolineCall()
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#include "pycore_interp.h" // PyInterpreterState.gc
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#include "pycore_pyatomic_ft_wrappers.h" // FT_ATOMIC_STORE_PTR_RELAXED
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#include "pycore_pystate.h" // _PyInterpreterState_GET()
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#include "pycore_typeid.h" // _PyType_IncrefSlow
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#define _Py_IMMORTAL_REFCNT_LOOSE ((_Py_IMMORTAL_REFCNT >> 1) + 1)
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// This value is added to `ob_ref_shared` for objects that use deferred
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// reference counting so that they are not immediately deallocated when the
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// non-deferred reference count drops to zero.
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//
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// The value is half the maximum shared refcount because the low two bits of
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// `ob_ref_shared` are used for flags.
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#define _Py_REF_DEFERRED (PY_SSIZE_T_MAX / 8)
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// gh-121528, gh-118997: Similar to _Py_IsImmortal() but be more loose when
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// comparing the reference count to stay compatible with C extensions built
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// with the stable ABI 3.11 or older. Such extensions implement INCREF/DECREF
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// as refcnt++ and refcnt-- without taking in account immortal objects. For
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// example, the reference count of an immortal object can change from
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// _Py_IMMORTAL_REFCNT to _Py_IMMORTAL_REFCNT+1 (INCREF) or
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// _Py_IMMORTAL_REFCNT-1 (DECREF).
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//
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// This function should only be used in assertions. Otherwise, _Py_IsImmortal()
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// must be used instead.
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static inline int _Py_IsImmortalLoose(PyObject *op)
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{
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#if defined(Py_GIL_DISABLED)
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return _Py_IsImmortal(op);
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#else
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return (op->ob_refcnt >= _Py_IMMORTAL_REFCNT_LOOSE);
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#endif
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}
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#define _Py_IsImmortalLoose(op) _Py_IsImmortalLoose(_PyObject_CAST(op))
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/* Check if an object is consistent. For example, ensure that the reference
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counter is greater than or equal to 1, and ensure that ob_type is not NULL.
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Call _PyObject_AssertFailed() if the object is inconsistent.
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If check_content is zero, only check header fields: reduce the overhead.
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The function always return 1. The return value is just here to be able to
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write:
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assert(_PyObject_CheckConsistency(obj, 1)); */
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extern int _PyObject_CheckConsistency(PyObject *op, int check_content);
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extern void _PyDebugAllocatorStats(FILE *out, const char *block_name,
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int num_blocks, size_t sizeof_block);
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extern void _PyObject_DebugTypeStats(FILE *out);
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#ifdef Py_TRACE_REFS
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// Forget a reference registered by _Py_NewReference(). Function called by
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// _Py_Dealloc().
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//
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// On a free list, the function can be used before modifying an object to
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// remove the object from traced objects. Then _Py_NewReference() or
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// _Py_NewReferenceNoTotal() should be called again on the object to trace
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// it again.
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extern void _Py_ForgetReference(PyObject *);
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#endif
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// Export for shared _testinternalcapi extension
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PyAPI_FUNC(int) _PyObject_IsFreed(PyObject *);
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/* We need to maintain an internal copy of Py{Var}Object_HEAD_INIT to avoid
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designated initializer conflicts in C++20. If we use the deinition in
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object.h, we will be mixing designated and non-designated initializers in
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pycore objects which is forbiddent in C++20. However, if we then use
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designated initializers in object.h then Extensions without designated break.
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Furthermore, we can't use designated initializers in Extensions since these
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are not supported pre-C++20. Thus, keeping an internal copy here is the most
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backwards compatible solution */
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#if defined(Py_GIL_DISABLED)
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#define _PyObject_HEAD_INIT(type) \
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{ \
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.ob_ref_local = _Py_IMMORTAL_REFCNT_LOCAL, \
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.ob_type = (type) \
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}
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#else
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#define _PyObject_HEAD_INIT(type) \
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{ \
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.ob_refcnt = _Py_IMMORTAL_REFCNT, \
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.ob_type = (type) \
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}
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#endif
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#define _PyVarObject_HEAD_INIT(type, size) \
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{ \
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.ob_base = _PyObject_HEAD_INIT(type), \
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.ob_size = size \
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}
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PyAPI_FUNC(void) _Py_NO_RETURN _Py_FatalRefcountErrorFunc(
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const char *func,
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const char *message);
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#define _Py_FatalRefcountError(message) \
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_Py_FatalRefcountErrorFunc(__func__, (message))
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#ifdef Py_REF_DEBUG
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/* The symbol is only exposed in the API for the sake of extensions
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built against the pre-3.12 stable ABI. */
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PyAPI_DATA(Py_ssize_t) _Py_RefTotal;
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extern void _Py_AddRefTotal(PyThreadState *, Py_ssize_t);
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extern void _Py_IncRefTotal(PyThreadState *);
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extern void _Py_DecRefTotal(PyThreadState *);
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# define _Py_DEC_REFTOTAL(interp) \
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interp->object_state.reftotal--
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#endif
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// Increment reference count by n
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static inline void _Py_RefcntAdd(PyObject* op, Py_ssize_t n)
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{
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if (_Py_IsImmortal(op)) {
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return;
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}
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#ifdef Py_REF_DEBUG
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_Py_AddRefTotal(_PyThreadState_GET(), n);
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#endif
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#if !defined(Py_GIL_DISABLED)
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op->ob_refcnt += n;
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#else
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if (_Py_IsOwnedByCurrentThread(op)) {
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uint32_t local = op->ob_ref_local;
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Py_ssize_t refcnt = (Py_ssize_t)local + n;
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# if PY_SSIZE_T_MAX > UINT32_MAX
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if (refcnt > (Py_ssize_t)UINT32_MAX) {
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// Make the object immortal if the 32-bit local reference count
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// would overflow.
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refcnt = _Py_IMMORTAL_REFCNT_LOCAL;
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}
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# endif
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_Py_atomic_store_uint32_relaxed(&op->ob_ref_local, (uint32_t)refcnt);
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}
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else {
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_Py_atomic_add_ssize(&op->ob_ref_shared, (n << _Py_REF_SHARED_SHIFT));
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}
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#endif
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}
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#define _Py_RefcntAdd(op, n) _Py_RefcntAdd(_PyObject_CAST(op), n)
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PyAPI_FUNC(void) _Py_SetImmortal(PyObject *op);
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PyAPI_FUNC(void) _Py_SetImmortalUntracked(PyObject *op);
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// Makes an immortal object mortal again with the specified refcnt. Should only
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// be used during runtime finalization.
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static inline void _Py_SetMortal(PyObject *op, Py_ssize_t refcnt)
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{
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if (op) {
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assert(_Py_IsImmortalLoose(op));
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#ifdef Py_GIL_DISABLED
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op->ob_tid = _Py_UNOWNED_TID;
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op->ob_ref_local = 0;
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op->ob_ref_shared = _Py_REF_SHARED(refcnt, _Py_REF_MERGED);
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#else
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op->ob_refcnt = refcnt;
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#endif
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}
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}
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/* _Py_ClearImmortal() should only be used during runtime finalization. */
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static inline void _Py_ClearImmortal(PyObject *op)
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{
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if (op) {
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_Py_SetMortal(op, 1);
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Py_DECREF(op);
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}
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}
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#define _Py_ClearImmortal(op) \
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do { \
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_Py_ClearImmortal(_PyObject_CAST(op)); \
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op = NULL; \
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} while (0)
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#if !defined(Py_GIL_DISABLED)
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static inline void
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_Py_DECREF_SPECIALIZED(PyObject *op, const destructor destruct)
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{
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if (_Py_IsImmortal(op)) {
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return;
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}
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_Py_DECREF_STAT_INC();
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#ifdef Py_REF_DEBUG
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_Py_DEC_REFTOTAL(PyInterpreterState_Get());
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#endif
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if (--op->ob_refcnt != 0) {
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assert(op->ob_refcnt > 0);
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}
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else {
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#ifdef Py_TRACE_REFS
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_Py_ForgetReference(op);
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#endif
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destruct(op);
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}
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}
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static inline void
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_Py_DECREF_NO_DEALLOC(PyObject *op)
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{
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if (_Py_IsImmortal(op)) {
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return;
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}
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_Py_DECREF_STAT_INC();
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#ifdef Py_REF_DEBUG
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_Py_DEC_REFTOTAL(PyInterpreterState_Get());
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#endif
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op->ob_refcnt--;
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#ifdef Py_DEBUG
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if (op->ob_refcnt <= 0) {
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_Py_FatalRefcountError("Expected a positive remaining refcount");
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}
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#endif
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}
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#else
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// TODO: implement Py_DECREF specializations for Py_GIL_DISABLED build
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static inline void
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_Py_DECREF_SPECIALIZED(PyObject *op, const destructor destruct)
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{
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Py_DECREF(op);
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}
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static inline void
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_Py_DECREF_NO_DEALLOC(PyObject *op)
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{
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Py_DECREF(op);
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}
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static inline int
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_Py_REF_IS_MERGED(Py_ssize_t ob_ref_shared)
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{
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return (ob_ref_shared & _Py_REF_SHARED_FLAG_MASK) == _Py_REF_MERGED;
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}
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static inline int
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_Py_REF_IS_QUEUED(Py_ssize_t ob_ref_shared)
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{
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return (ob_ref_shared & _Py_REF_SHARED_FLAG_MASK) == _Py_REF_QUEUED;
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}
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// Merge the local and shared reference count fields and add `extra` to the
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// refcount when merging.
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Py_ssize_t _Py_ExplicitMergeRefcount(PyObject *op, Py_ssize_t extra);
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#endif // !defined(Py_GIL_DISABLED)
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#ifdef Py_REF_DEBUG
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# undef _Py_DEC_REFTOTAL
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#endif
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extern int _PyType_CheckConsistency(PyTypeObject *type);
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extern int _PyDict_CheckConsistency(PyObject *mp, int check_content);
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/* Update the Python traceback of an object. This function must be called
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when a memory block is reused from a free list.
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Internal function called by _Py_NewReference(). */
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extern int _PyTraceMalloc_TraceRef(PyObject *op, PyRefTracerEvent event, void*);
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// Fast inlined version of PyType_HasFeature()
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static inline int
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_PyType_HasFeature(PyTypeObject *type, unsigned long feature) {
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return ((FT_ATOMIC_LOAD_ULONG_RELAXED(type->tp_flags) & feature) != 0);
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}
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extern void _PyType_InitCache(PyInterpreterState *interp);
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extern PyStatus _PyObject_InitState(PyInterpreterState *interp);
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extern void _PyObject_FiniState(PyInterpreterState *interp);
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extern bool _PyRefchain_IsTraced(PyInterpreterState *interp, PyObject *obj);
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#ifndef Py_GIL_DISABLED
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# define _Py_INCREF_TYPE Py_INCREF
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# define _Py_DECREF_TYPE Py_DECREF
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#else
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static inline void
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_Py_INCREF_TYPE(PyTypeObject *type)
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{
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if (!_PyType_HasFeature(type, Py_TPFLAGS_HEAPTYPE)) {
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assert(_Py_IsImmortal(type));
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return;
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}
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// gh-122974: GCC 11 warns about the access to PyHeapTypeObject fields when
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// _Py_INCREF_TYPE() is called on a statically allocated type. The
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// _PyType_HasFeature check above ensures that the type is a heap type.
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#if defined(__GNUC__) && __GNUC__ >= 11
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# pragma GCC diagnostic push
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# pragma GCC diagnostic ignored "-Warray-bounds"
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#endif
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_PyThreadStateImpl *tstate = (_PyThreadStateImpl *)_PyThreadState_GET();
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PyHeapTypeObject *ht = (PyHeapTypeObject *)type;
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// Unsigned comparison so that `unique_id=-1`, which indicates that
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// per-thread refcounting has been disabled on this type, is handled by
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// the "else".
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if ((size_t)ht->unique_id < (size_t)tstate->types.size) {
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# ifdef Py_REF_DEBUG
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_Py_INCREF_IncRefTotal();
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# endif
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_Py_INCREF_STAT_INC();
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tstate->types.refcounts[ht->unique_id]++;
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}
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else {
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// The slow path resizes the thread-local refcount array if necessary.
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// It handles the unique_id=-1 case to keep the inlinable function smaller.
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_PyType_IncrefSlow(ht);
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}
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#if defined(__GNUC__) && __GNUC__ >= 11
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# pragma GCC diagnostic pop
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#endif
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}
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static inline void
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_Py_DECREF_TYPE(PyTypeObject *type)
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{
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if (!_PyType_HasFeature(type, Py_TPFLAGS_HEAPTYPE)) {
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assert(_Py_IsImmortal(type));
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return;
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}
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_PyThreadStateImpl *tstate = (_PyThreadStateImpl *)_PyThreadState_GET();
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PyHeapTypeObject *ht = (PyHeapTypeObject *)type;
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// Unsigned comparison so that `unique_id=-1`, which indicates that
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// per-thread refcounting has been disabled on this type, is handled by
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// the "else".
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if ((size_t)ht->unique_id < (size_t)tstate->types.size) {
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# ifdef Py_REF_DEBUG
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_Py_DECREF_DecRefTotal();
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# endif
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_Py_DECREF_STAT_INC();
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tstate->types.refcounts[ht->unique_id]--;
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}
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else {
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// Directly decref the type if the type id is not assigned or if
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// per-thread refcounting has been disabled on this type.
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Py_DECREF(type);
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}
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}
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#endif
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/* Inline functions trading binary compatibility for speed:
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_PyObject_Init() is the fast version of PyObject_Init(), and
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_PyObject_InitVar() is the fast version of PyObject_InitVar().
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These inline functions must not be called with op=NULL. */
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static inline void
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_PyObject_Init(PyObject *op, PyTypeObject *typeobj)
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{
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assert(op != NULL);
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Py_SET_TYPE(op, typeobj);
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assert(_PyType_HasFeature(typeobj, Py_TPFLAGS_HEAPTYPE) || _Py_IsImmortalLoose(typeobj));
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_Py_INCREF_TYPE(typeobj);
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_Py_NewReference(op);
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}
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static inline void
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_PyObject_InitVar(PyVarObject *op, PyTypeObject *typeobj, Py_ssize_t size)
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{
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assert(op != NULL);
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assert(typeobj != &PyLong_Type);
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_PyObject_Init((PyObject *)op, typeobj);
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Py_SET_SIZE(op, size);
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}
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/* Tell the GC to track this object.
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*
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* The object must not be tracked by the GC.
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*
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* NB: While the object is tracked by the collector, it must be safe to call the
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* ob_traverse method.
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*
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* Internal note: interp->gc.generation0->_gc_prev doesn't have any bit flags
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* because it's not object header. So we don't use _PyGCHead_PREV() and
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* _PyGCHead_SET_PREV() for it to avoid unnecessary bitwise operations.
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*
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* See also the public PyObject_GC_Track() function.
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*/
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static inline void _PyObject_GC_TRACK(
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// The preprocessor removes _PyObject_ASSERT_FROM() calls if NDEBUG is defined
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#ifndef NDEBUG
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const char *filename, int lineno,
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#endif
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PyObject *op)
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{
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_PyObject_ASSERT_FROM(op, !_PyObject_GC_IS_TRACKED(op),
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"object already tracked by the garbage collector",
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filename, lineno, __func__);
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#ifdef Py_GIL_DISABLED
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_PyObject_SET_GC_BITS(op, _PyGC_BITS_TRACKED);
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#else
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PyGC_Head *gc = _Py_AS_GC(op);
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_PyObject_ASSERT_FROM(op,
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(gc->_gc_prev & _PyGC_PREV_MASK_COLLECTING) == 0,
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"object is in generation which is garbage collected",
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filename, lineno, __func__);
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PyInterpreterState *interp = _PyInterpreterState_GET();
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PyGC_Head *generation0 = &interp->gc.young.head;
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PyGC_Head *last = (PyGC_Head*)(generation0->_gc_prev);
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_PyGCHead_SET_NEXT(last, gc);
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_PyGCHead_SET_PREV(gc, last);
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/* Young objects will be moved into the visited space during GC, so set the bit here */
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gc->_gc_next = ((uintptr_t)generation0) | interp->gc.visited_space;
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generation0->_gc_prev = (uintptr_t)gc;
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#endif
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}
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/* Tell the GC to stop tracking this object.
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*
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* Internal note: This may be called while GC. So _PyGC_PREV_MASK_COLLECTING
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* must be cleared. But _PyGC_PREV_MASK_FINALIZED bit is kept.
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*
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* The object must be tracked by the GC.
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*
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* See also the public PyObject_GC_UnTrack() which accept an object which is
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* not tracked.
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*/
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static inline void _PyObject_GC_UNTRACK(
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// The preprocessor removes _PyObject_ASSERT_FROM() calls if NDEBUG is defined
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#ifndef NDEBUG
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const char *filename, int lineno,
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#endif
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PyObject *op)
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{
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_PyObject_ASSERT_FROM(op, _PyObject_GC_IS_TRACKED(op),
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"object not tracked by the garbage collector",
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filename, lineno, __func__);
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#ifdef Py_GIL_DISABLED
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_PyObject_CLEAR_GC_BITS(op, _PyGC_BITS_TRACKED);
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#else
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PyGC_Head *gc = _Py_AS_GC(op);
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PyGC_Head *prev = _PyGCHead_PREV(gc);
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PyGC_Head *next = _PyGCHead_NEXT(gc);
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_PyGCHead_SET_NEXT(prev, next);
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_PyGCHead_SET_PREV(next, prev);
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gc->_gc_next = 0;
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gc->_gc_prev &= _PyGC_PREV_MASK_FINALIZED;
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#endif
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}
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// Macros to accept any type for the parameter, and to automatically pass
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// the filename and the filename (if NDEBUG is not defined) where the macro
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// is called.
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#ifdef NDEBUG
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# define _PyObject_GC_TRACK(op) \
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|
_PyObject_GC_TRACK(_PyObject_CAST(op))
|
|
# define _PyObject_GC_UNTRACK(op) \
|
|
_PyObject_GC_UNTRACK(_PyObject_CAST(op))
|
|
#else
|
|
# define _PyObject_GC_TRACK(op) \
|
|
_PyObject_GC_TRACK(__FILE__, __LINE__, _PyObject_CAST(op))
|
|
# define _PyObject_GC_UNTRACK(op) \
|
|
_PyObject_GC_UNTRACK(__FILE__, __LINE__, _PyObject_CAST(op))
|
|
#endif
|
|
|
|
#ifdef Py_GIL_DISABLED
|
|
|
|
/* Tries to increment an object's reference count
|
|
*
|
|
* This is a specialized version of _Py_TryIncref that only succeeds if the
|
|
* object is immortal or local to this thread. It does not handle the case
|
|
* where the reference count modification requires an atomic operation. This
|
|
* allows call sites to specialize for the immortal/local case.
|
|
*/
|
|
static inline int
|
|
_Py_TryIncrefFast(PyObject *op) {
|
|
uint32_t local = _Py_atomic_load_uint32_relaxed(&op->ob_ref_local);
|
|
local += 1;
|
|
if (local == 0) {
|
|
// immortal
|
|
return 1;
|
|
}
|
|
if (_Py_IsOwnedByCurrentThread(op)) {
|
|
_Py_INCREF_STAT_INC();
|
|
_Py_atomic_store_uint32_relaxed(&op->ob_ref_local, local);
|
|
#ifdef Py_REF_DEBUG
|
|
_Py_IncRefTotal(_PyThreadState_GET());
|
|
#endif
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static inline int
|
|
_Py_TryIncRefShared(PyObject *op)
|
|
{
|
|
Py_ssize_t shared = _Py_atomic_load_ssize_relaxed(&op->ob_ref_shared);
|
|
for (;;) {
|
|
// If the shared refcount is zero and the object is either merged
|
|
// or may not have weak references, then we cannot incref it.
|
|
if (shared == 0 || shared == _Py_REF_MERGED) {
|
|
return 0;
|
|
}
|
|
|
|
if (_Py_atomic_compare_exchange_ssize(
|
|
&op->ob_ref_shared,
|
|
&shared,
|
|
shared + (1 << _Py_REF_SHARED_SHIFT))) {
|
|
#ifdef Py_REF_DEBUG
|
|
_Py_IncRefTotal(_PyThreadState_GET());
|
|
#endif
|
|
_Py_INCREF_STAT_INC();
|
|
return 1;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Tries to incref the object op and ensures that *src still points to it. */
|
|
static inline int
|
|
_Py_TryIncrefCompare(PyObject **src, PyObject *op)
|
|
{
|
|
if (_Py_TryIncrefFast(op)) {
|
|
return 1;
|
|
}
|
|
if (!_Py_TryIncRefShared(op)) {
|
|
return 0;
|
|
}
|
|
if (op != _Py_atomic_load_ptr(src)) {
|
|
Py_DECREF(op);
|
|
return 0;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
/* Loads and increfs an object from ptr, which may contain a NULL value.
|
|
Safe with concurrent (atomic) updates to ptr.
|
|
NOTE: The writer must set maybe-weakref on the stored object! */
|
|
static inline PyObject *
|
|
_Py_XGetRef(PyObject **ptr)
|
|
{
|
|
for (;;) {
|
|
PyObject *value = _Py_atomic_load_ptr(ptr);
|
|
if (value == NULL) {
|
|
return value;
|
|
}
|
|
if (_Py_TryIncrefCompare(ptr, value)) {
|
|
return value;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Attempts to loads and increfs an object from ptr. Returns NULL
|
|
on failure, which may be due to a NULL value or a concurrent update. */
|
|
static inline PyObject *
|
|
_Py_TryXGetRef(PyObject **ptr)
|
|
{
|
|
PyObject *value = _Py_atomic_load_ptr(ptr);
|
|
if (value == NULL) {
|
|
return value;
|
|
}
|
|
if (_Py_TryIncrefCompare(ptr, value)) {
|
|
return value;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
/* Like Py_NewRef but also optimistically sets _Py_REF_MAYBE_WEAKREF
|
|
on objects owned by a different thread. */
|
|
static inline PyObject *
|
|
_Py_NewRefWithLock(PyObject *op)
|
|
{
|
|
if (_Py_TryIncrefFast(op)) {
|
|
return op;
|
|
}
|
|
#ifdef Py_REF_DEBUG
|
|
_Py_IncRefTotal(_PyThreadState_GET());
|
|
#endif
|
|
_Py_INCREF_STAT_INC();
|
|
for (;;) {
|
|
Py_ssize_t shared = _Py_atomic_load_ssize_relaxed(&op->ob_ref_shared);
|
|
Py_ssize_t new_shared = shared + (1 << _Py_REF_SHARED_SHIFT);
|
|
if ((shared & _Py_REF_SHARED_FLAG_MASK) == 0) {
|
|
new_shared |= _Py_REF_MAYBE_WEAKREF;
|
|
}
|
|
if (_Py_atomic_compare_exchange_ssize(
|
|
&op->ob_ref_shared,
|
|
&shared,
|
|
new_shared)) {
|
|
return op;
|
|
}
|
|
}
|
|
}
|
|
|
|
static inline PyObject *
|
|
_Py_XNewRefWithLock(PyObject *obj)
|
|
{
|
|
if (obj == NULL) {
|
|
return NULL;
|
|
}
|
|
return _Py_NewRefWithLock(obj);
|
|
}
|
|
|
|
static inline void
|
|
_PyObject_SetMaybeWeakref(PyObject *op)
|
|
{
|
|
if (_Py_IsImmortal(op)) {
|
|
return;
|
|
}
|
|
for (;;) {
|
|
Py_ssize_t shared = _Py_atomic_load_ssize_relaxed(&op->ob_ref_shared);
|
|
if ((shared & _Py_REF_SHARED_FLAG_MASK) != 0) {
|
|
// Nothing to do if it's in WEAKREFS, QUEUED, or MERGED states.
|
|
return;
|
|
}
|
|
if (_Py_atomic_compare_exchange_ssize(
|
|
&op->ob_ref_shared, &shared, shared | _Py_REF_MAYBE_WEAKREF)) {
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
|
|
#endif
|
|
|
|
/* Tries to incref op and returns 1 if successful or 0 otherwise. */
|
|
static inline int
|
|
_Py_TryIncref(PyObject *op)
|
|
{
|
|
#ifdef Py_GIL_DISABLED
|
|
return _Py_TryIncrefFast(op) || _Py_TryIncRefShared(op);
|
|
#else
|
|
if (Py_REFCNT(op) > 0) {
|
|
Py_INCREF(op);
|
|
return 1;
|
|
}
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
#ifdef Py_REF_DEBUG
|
|
extern void _PyInterpreterState_FinalizeRefTotal(PyInterpreterState *);
|
|
extern void _Py_FinalizeRefTotal(_PyRuntimeState *);
|
|
extern void _PyDebug_PrintTotalRefs(void);
|
|
#endif
|
|
|
|
#ifdef Py_TRACE_REFS
|
|
extern void _Py_AddToAllObjects(PyObject *op);
|
|
extern void _Py_PrintReferences(PyInterpreterState *, FILE *);
|
|
extern void _Py_PrintReferenceAddresses(PyInterpreterState *, FILE *);
|
|
#endif
|
|
|
|
|
|
/* Return the *address* of the object's weaklist. The address may be
|
|
* dereferenced to get the current head of the weaklist. This is useful
|
|
* for iterating over the linked list of weakrefs, especially when the
|
|
* list is being modified externally (e.g. refs getting removed).
|
|
*
|
|
* The returned pointer should not be used to change the head of the list
|
|
* nor should it be used to add, remove, or swap any refs in the list.
|
|
* That is the sole responsibility of the code in weakrefobject.c.
|
|
*/
|
|
static inline PyObject **
|
|
_PyObject_GET_WEAKREFS_LISTPTR(PyObject *op)
|
|
{
|
|
if (PyType_Check(op) &&
|
|
((PyTypeObject *)op)->tp_flags & _Py_TPFLAGS_STATIC_BUILTIN) {
|
|
PyInterpreterState *interp = _PyInterpreterState_GET();
|
|
managed_static_type_state *state = _PyStaticType_GetState(
|
|
interp, (PyTypeObject *)op);
|
|
return _PyStaticType_GET_WEAKREFS_LISTPTR(state);
|
|
}
|
|
// Essentially _PyObject_GET_WEAKREFS_LISTPTR_FROM_OFFSET():
|
|
Py_ssize_t offset = Py_TYPE(op)->tp_weaklistoffset;
|
|
return (PyObject **)((char *)op + offset);
|
|
}
|
|
|
|
/* This is a special case of _PyObject_GET_WEAKREFS_LISTPTR().
|
|
* Only the most fundamental lookup path is used.
|
|
* Consequently, static types should not be used.
|
|
*
|
|
* For static builtin types the returned pointer will always point
|
|
* to a NULL tp_weaklist. This is fine for any deallocation cases,
|
|
* since static types are never deallocated and static builtin types
|
|
* are only finalized at the end of runtime finalization.
|
|
*
|
|
* If the weaklist for static types is actually needed then use
|
|
* _PyObject_GET_WEAKREFS_LISTPTR().
|
|
*/
|
|
static inline PyWeakReference **
|
|
_PyObject_GET_WEAKREFS_LISTPTR_FROM_OFFSET(PyObject *op)
|
|
{
|
|
assert(!PyType_Check(op) ||
|
|
((PyTypeObject *)op)->tp_flags & Py_TPFLAGS_HEAPTYPE);
|
|
Py_ssize_t offset = Py_TYPE(op)->tp_weaklistoffset;
|
|
return (PyWeakReference **)((char *)op + offset);
|
|
}
|
|
|
|
// Fast inlined version of PyObject_IS_GC()
|
|
static inline int
|
|
_PyObject_IS_GC(PyObject *obj)
|
|
{
|
|
PyTypeObject *type = Py_TYPE(obj);
|
|
return (PyType_IS_GC(type)
|
|
&& (type->tp_is_gc == NULL || type->tp_is_gc(obj)));
|
|
}
|
|
|
|
// Fast inlined version of PyObject_Hash()
|
|
static inline Py_hash_t
|
|
_PyObject_HashFast(PyObject *op)
|
|
{
|
|
if (PyUnicode_CheckExact(op)) {
|
|
Py_hash_t hash = FT_ATOMIC_LOAD_SSIZE_RELAXED(
|
|
_PyASCIIObject_CAST(op)->hash);
|
|
if (hash != -1) {
|
|
return hash;
|
|
}
|
|
}
|
|
return PyObject_Hash(op);
|
|
}
|
|
|
|
// Fast inlined version of PyType_IS_GC()
|
|
#define _PyType_IS_GC(t) _PyType_HasFeature((t), Py_TPFLAGS_HAVE_GC)
|
|
|
|
static inline size_t
|
|
_PyType_PreHeaderSize(PyTypeObject *tp)
|
|
{
|
|
return (
|
|
#ifndef Py_GIL_DISABLED
|
|
_PyType_IS_GC(tp) * sizeof(PyGC_Head) +
|
|
#endif
|
|
_PyType_HasFeature(tp, Py_TPFLAGS_PREHEADER) * 2 * sizeof(PyObject *)
|
|
);
|
|
}
|
|
|
|
void _PyObject_GC_Link(PyObject *op);
|
|
|
|
// Usage: assert(_Py_CheckSlotResult(obj, "__getitem__", result != NULL));
|
|
extern int _Py_CheckSlotResult(
|
|
PyObject *obj,
|
|
const char *slot_name,
|
|
int success);
|
|
|
|
// Test if a type supports weak references
|
|
static inline int _PyType_SUPPORTS_WEAKREFS(PyTypeObject *type) {
|
|
return (type->tp_weaklistoffset != 0);
|
|
}
|
|
|
|
extern PyObject* _PyType_AllocNoTrack(PyTypeObject *type, Py_ssize_t nitems);
|
|
PyAPI_FUNC(PyObject *) _PyType_NewManagedObject(PyTypeObject *type);
|
|
|
|
extern PyTypeObject* _PyType_CalculateMetaclass(PyTypeObject *, PyObject *);
|
|
extern PyObject* _PyType_GetDocFromInternalDoc(const char *, const char *);
|
|
extern PyObject* _PyType_GetTextSignatureFromInternalDoc(const char *, const char *, int);
|
|
extern int _PyObject_SetAttributeErrorContext(PyObject *v, PyObject* name);
|
|
|
|
void _PyObject_InitInlineValues(PyObject *obj, PyTypeObject *tp);
|
|
extern int _PyObject_StoreInstanceAttribute(PyObject *obj,
|
|
PyObject *name, PyObject *value);
|
|
extern bool _PyObject_TryGetInstanceAttribute(PyObject *obj, PyObject *name,
|
|
PyObject **attr);
|
|
|
|
#ifdef Py_GIL_DISABLED
|
|
# define MANAGED_DICT_OFFSET (((Py_ssize_t)sizeof(PyObject *))*-1)
|
|
# define MANAGED_WEAKREF_OFFSET (((Py_ssize_t)sizeof(PyObject *))*-2)
|
|
#else
|
|
# define MANAGED_DICT_OFFSET (((Py_ssize_t)sizeof(PyObject *))*-3)
|
|
# define MANAGED_WEAKREF_OFFSET (((Py_ssize_t)sizeof(PyObject *))*-4)
|
|
#endif
|
|
|
|
typedef union {
|
|
PyDictObject *dict;
|
|
} PyManagedDictPointer;
|
|
|
|
static inline PyManagedDictPointer *
|
|
_PyObject_ManagedDictPointer(PyObject *obj)
|
|
{
|
|
assert(Py_TYPE(obj)->tp_flags & Py_TPFLAGS_MANAGED_DICT);
|
|
return (PyManagedDictPointer *)((char *)obj + MANAGED_DICT_OFFSET);
|
|
}
|
|
|
|
static inline PyDictObject *
|
|
_PyObject_GetManagedDict(PyObject *obj)
|
|
{
|
|
PyManagedDictPointer *dorv = _PyObject_ManagedDictPointer(obj);
|
|
return (PyDictObject *)FT_ATOMIC_LOAD_PTR_ACQUIRE(dorv->dict);
|
|
}
|
|
|
|
static inline PyDictValues *
|
|
_PyObject_InlineValues(PyObject *obj)
|
|
{
|
|
PyTypeObject *tp = Py_TYPE(obj);
|
|
assert(tp->tp_basicsize > 0 && tp->tp_basicsize % sizeof(PyObject *) == 0);
|
|
assert(Py_TYPE(obj)->tp_flags & Py_TPFLAGS_INLINE_VALUES);
|
|
assert(Py_TYPE(obj)->tp_flags & Py_TPFLAGS_MANAGED_DICT);
|
|
return (PyDictValues *)((char *)obj + tp->tp_basicsize);
|
|
}
|
|
|
|
extern PyObject ** _PyObject_ComputedDictPointer(PyObject *);
|
|
extern int _PyObject_IsInstanceDictEmpty(PyObject *);
|
|
|
|
// Export for 'math' shared extension
|
|
PyAPI_FUNC(PyObject*) _PyObject_LookupSpecial(PyObject *, PyObject *);
|
|
PyAPI_FUNC(PyObject*) _PyObject_LookupSpecialMethod(PyObject *self, PyObject *attr, PyObject **self_or_null);
|
|
|
|
extern int _PyObject_IsAbstract(PyObject *);
|
|
|
|
PyAPI_FUNC(int) _PyObject_GetMethod(PyObject *obj, PyObject *name, PyObject **method);
|
|
extern PyObject* _PyObject_NextNotImplemented(PyObject *);
|
|
|
|
// Pickle support.
|
|
// Export for '_datetime' shared extension
|
|
PyAPI_FUNC(PyObject*) _PyObject_GetState(PyObject *);
|
|
|
|
/* C function call trampolines to mitigate bad function pointer casts.
|
|
*
|
|
* Typical native ABIs ignore additional arguments or fill in missing
|
|
* values with 0/NULL in function pointer cast. Compilers do not show
|
|
* warnings when a function pointer is explicitly casted to an
|
|
* incompatible type.
|
|
*
|
|
* Bad fpcasts are an issue in WebAssembly. WASM's indirect_call has strict
|
|
* function signature checks. Argument count, types, and return type must
|
|
* match.
|
|
*
|
|
* Third party code unintentionally rely on problematic fpcasts. The call
|
|
* trampoline mitigates common occurrences of bad fpcasts on Emscripten.
|
|
*/
|
|
#if !(defined(__EMSCRIPTEN__) && defined(PY_CALL_TRAMPOLINE))
|
|
#define _PyCFunction_TrampolineCall(meth, self, args) \
|
|
(meth)((self), (args))
|
|
#define _PyCFunctionWithKeywords_TrampolineCall(meth, self, args, kw) \
|
|
(meth)((self), (args), (kw))
|
|
#endif // __EMSCRIPTEN__ && PY_CALL_TRAMPOLINE
|
|
|
|
// Export these 2 symbols for '_pickle' shared extension
|
|
PyAPI_DATA(PyTypeObject) _PyNone_Type;
|
|
PyAPI_DATA(PyTypeObject) _PyNotImplemented_Type;
|
|
|
|
// Maps Py_LT to Py_GT, ..., Py_GE to Py_LE.
|
|
// Export for the stable ABI.
|
|
PyAPI_DATA(int) _Py_SwappedOp[];
|
|
|
|
extern void _Py_GetConstant_Init(void);
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
#endif /* !Py_INTERNAL_OBJECT_H */
|