8000 bpo-35081: Move _PyObject_GC_TRACK() to pycore_object.h by vstinner · Pull Request #10276 · python/cpython · GitHub
[go: up one dir, main page]

Skip to content

bpo-35081: Move _PyObject_GC_TRACK() to pycore_object.h #10276

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
wants to merge 1 commit into from
Closed
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
bpo-35081: Move _PyObject_GC_TRACK() to pycore_object.h
* Create Include/internal/pycore_object.h
* Move _PyObject_GC_TRACK() and _PyObject_GC_UNTRACK() macros to
  pycore_object.h
* Remove _PyGC_generation0: replaced with _PyRuntime.gc.generation0
* Python.h now automatically includes pycore_object.h
  • Loading branch information
vstinner committed Nov 13, 2018
commit 204b53aec2d266c494e967679b54b178559da901
6 changes: 6 additions & 0 deletions Include/Python.h
Original file line number Diff line number Diff line change
Expand Up @@ -146,4 +146,10 @@
#include "pyfpe.h"
#include "tracemalloc.h"

#if defined(Py_BUILD_CORE) || defined(Py_BUILD_CORE_BUILTIN)
/* bpo-35081: Automatically include pycore_object.h in Python.h, to avoid
to have to add an explicit #include "pycore_object.h" to each C file. */
# include "pycore_object.h"
#endif

#endif /* !Py_PYTHON_H */
91 changes: 91 additions & 0 deletions Include/internal/pycore_object.h
Original file line number Diff line number Diff line change
@@ -0,0 +1,91 @@
#ifndef Py_INTERNAL_OBECT_H
#define Py_INTERNAL_OBECT_H
#ifdef __cplusplus
extern "C" {
#endif

#if !defined(Py_BUILD_CORE) && !defined(Py_BUILD_CORE_BUILTIN)
# error "this header requires Py_BUILD_CORE or Py_BUILD_CORE_BUILTIN defined"
#endif

#include "pycore_pystate.h" /* _PyRuntime */

/* Bit flags for _gc_prev */
/* Bit 0 is set when tp_finalize is called */
#define _PyGC_PREV_MASK_FINALIZED (1)
/* Bit 1 is set when the object is in generation which is GCed currently. */
#define _PyGC_PREV_MASK_COLLECTING (2)
/* The (N-2) most significant bits contain the real address. */
#define _PyGC_PREV_SHIFT (2)
#define _PyGC_PREV_MASK (((uintptr_t) -1) << _PyGC_PREV_SHIFT)


// Lowest bit of _gc_next is used for flags only in GC.
// But it is always 0 for normal code.
#define _PyGCHead_NEXT(g) ((PyGC_Head*)(g)->_gc_next)
#define _PyGCHead_SET_NEXT(g, p) ((g)->_gc_next = (uintptr_t)(p))

// Lowest two bits of _gc_prev is used for _PyGC_PREV_MASK_* flags.
#define _PyGCHead_PREV(g) ((PyGC_Head*)((g)->_gc_prev & _PyGC_PREV_MASK))
#define _PyGCHead_SET_PREV(g, p) do { \
assert(((uintptr_t)p & ~_PyGC_PREV_MASK) == 0); \
(g)->_gc_prev = ((g)->_gc_prev & ~_PyGC_PREV_MASK) \
| ((uintptr_t)(p)); \
} while (0)


#define _PyGCHead_FINALIZED(g) \
(((g)->_gc_prev & _PyGC_PREV_MASK_FINALIZED) != 0)
#define _PyGCHead_SET_FINALIZED(g) \
((g)->_gc_prev |= _PyGC_PREV_MASK_FINALIZED)

#define _PyGC_FINALIZED(o) \
_PyGCHead_FINALIZED(_Py_AS_GC(o))
#define _PyGC_SET_FINALIZED(o) \
_PyGCHead_SET_FINALIZED(_Py_AS_GC(o))


/* Tell the GC to track this object.
*
* NB: While the object is tracked by the collector, it must be safe to call the
* ob_traverse method.
*
* Internal note: _PyRuntime.gc.generation0->_gc_prev doesn't have any bit flags
* because it's not object header. So we don't use _PyGCHead_PREV() and
* _PyGCHead_SET_PREV() for it to avoid unnecessary bitwise operations.
*/
#define _PyObject_GC_TRACK(o) do { \
PyGC_Head *g = _Py_AS_GC(o); \
if (g->_gc_next != 0) { \
Py_FatalError("GC object already tracked"); \
} \
assert((g->_gc_prev & _PyGC_PREV_MASK_COLLECTING) == 0); \
PyGC_Head *last = (PyGC_Head*)(_PyRuntime.gc.generation0->_gc_prev); \
_PyGCHead_SET_NEXT(last, g); \
_PyGCHead_SET_PREV(g, last); \
_PyGCHead_SET_NEXT(g, _PyRuntime.gc.generation0); \
_PyRuntime.gc.generation0->_gc_prev = (uintptr_t)g; \
} while (0);


/* Tell the GC to stop tracking this object.
*
* Internal note: This may be called while GC. So _PyGC_PREV_MASK_COLLECTING must
* be cleared. But _PyGC_PREV_MASK_FINALIZED bit is kept.
*/
#define _PyObject_GC_UNTRACK(o) do { \
PyGC_Head *g = _Py_AS_GC(o); \
PyGC_Head *prev = _PyGCHead_PREV(g); \
PyGC_Head *next = _PyGCHead_NEXT(g); \
assert(next != NULL); \
_PyGCHead_SET_NEXT(prev, next); \
_PyGCHead_SET_PREV(next, prev); \
g->_gc_next = 0; \
g->_gc_prev &= _PyGC_PREV_MASK_FINALIZED; \
} while (0);


#ifdef __cplusplus
}
#endif
#endif /* !Py_INTERNAL_OBECT_H */
78 changes: 0 additions & 78 deletions Include/objimpl.h
Original file line number Diff line number Diff line change
Expand Up @@ -290,84 +290,6 @@ typedef struct {
(!PyTuple_CheckExact(obj) || _PyObject_GC_IS_TRACKED(obj)))
#endif


#if defined(Py_BUILD_CORE) || defined(Py_BUILD_CORE_BUILTIN)

/* Bit flags for _gc_prev */
/* Bit 0 is set when tp_finalize is called */
#define _PyGC_PREV_MASK_FINALIZED (1)
/* Bit 1 is set when the object is in generation which is GCed currently. */
#define _PyGC_PREV_MASK_COLLECTING (2)
/* The (N-2) most significant bits contain the real address. */
#define _PyGC_PREV_SHIFT (2)
#define _PyGC_PREV_MASK (((uintptr_t) -1) << _PyGC_PREV_SHIFT)

// Lowest bit of _gc_next is used for flags only in GC.
// But it is always 0 for normal code.
#define _PyGCHead_NEXT(g) ((PyGC_Head*)(g)->_gc_next)
#define _PyGCHead_SET_NEXT(g, p) ((g)->_gc_next = (uintptr_t)(p))

// Lowest two bits of _gc_prev is used for _PyGC_PREV_MASK_* flags.
#define _PyGCHead_PREV(g) ((PyGC_Head*)((g)->_gc_prev & _PyGC_PREV_MASK))
#define _PyGCHead_SET_PREV(g, p) do { \
assert(((uintptr_t)p & ~_PyGC_PREV_MASK) == 0); \
(g)->_gc_prev = ((g)->_gc_prev & ~_PyGC_PREV_MASK) \
| ((uintptr_t)(p)); \
} while (0)

#define _PyGCHead_FINALIZED(g) \
(((g)->_gc_prev & _PyGC_PREV_MASK_FINALIZED) != 0)
#define _PyGCHead_SET_FINALIZED(g) \
((g)->_gc_prev |= _PyGC_PREV_MASK_FINALIZED)

#define _PyGC_FINALIZED(o) \
_PyGCHead_FINALIZED(_Py_AS_GC(o))
#define _PyGC_SET_FINALIZED(o) \
_PyGCHead_SET_FINALIZED(_Py_AS_GC(o))

/* Tell the GC to track this object.
*
* NB: While the object is tracked by the collector, it must be safe to call the
* ob_traverse method.
*
* Internal note: _PyRuntime.gc.generation0->_gc_prev doesn't have any bit flags
* because it's not object header. So we don't use _PyGCHead_PREV() and
* _PyGCHead_SET_PREV() for it to avoid unnecessary bitwise operations.
*
* The PyObject_GC_Track() function is the public version of this macro.
*/
#define _PyObject_GC_TRACK(o) do { \
PyGC_Head *g = _Py_AS_GC(o); \
if (g->_gc_next != 0) { \
Py_FatalError("GC object already tracked"); \
} \
assert((g->_gc_prev & _PyGC_PREV_MASK_COLLECTING) == 0); \
PyGC_Head *last = (PyGC_Head*)(_PyRuntime.gc.generation0->_gc_prev); \
_PyGCHead_SET_NEXT(last, g); \
_PyGCHead_SET_PREV(g, last); \
_PyGCHead_SET_NEXT(g, _PyRuntime.gc.generation0); \
_PyRuntime.gc.generation0->_gc_prev = (uintptr_t)g; \
} while (0);

/* Tell the GC to stop tracking this object.
*
* Internal note: This may be called while GC. So _PyGC_PREV_MASK_COLLECTING must
* be cleared. But _PyGC_PREV_MASK_FINALIZED bit is kept.
*
* The PyObject_GC_UnTrack() function is the public version of this macro.
*/
#define _PyObject_GC_UNTRACK(o) do { \
PyGC_Head *g = _Py_AS_GC(o); \
PyGC_Head *prev = _PyGCHead_PREV(g); \
PyGC_Head *next = _PyGCHead_NEXT(g); \
assert(next != NULL); \
_PyGCHead_SET_NEXT(prev, next); \
_PyGCHead_SET_PREV(next, prev); \
g->_gc_next = 0; \
g->_gc_prev &= _PyGC_PREV_MASK_FINALIZED; \
} while (0);
#endif /* defined(Py_BUILD_CORE) || defined(Py_BUILD_CORE_BUILTIN) */

#ifndef Py_LIMITED_API
PyAPI_FUNC(PyObject *) _PyObject_GC_Malloc(size_t size);
PyAPI_FUNC(PyObject *) _PyObject_GC_Calloc(size_t size);
Expand Down
0