Commit Graph

83 Commits

Author SHA1 Message Date
Gregory P. Smith e348c8d154 Using 'long double' to force this structure to be worst case aligned is no
longer required as of Python 2.5+ when the gc_refs changed from an int (4
bytes) to a Py_ssize_t (8 bytes) as the minimum size is 16 bytes.

The use of a 'long double' triggered a warning by Clang trunk's
Undefined-Behavior Sanitizer as on many platforms a long double requires
16-byte alignment but the Python memory allocator only guarantees 8 byte
alignment.

So our code would allocate and use these structures with technically improper
alignment.  Though it didn't matter since the 'dummy' field is never used.
This silences that warning.

Spelunking into code history, the double was added in 2001 to force better
alignment on some platforms and changed to a long double in 2002 to appease
Tru64.  That issue should no loner be present since the upgrade from int to
Py_ssize_t where the minimum structure size increased to 16 (unless anyone
knows of a platform where ssize_t is 4 bytes?) or 24 bytes depending on if the
build uses 4 or 8 byte pointers.

We can probably get rid of the double and this union hack all together today.
That is a slightly more invasive change that can be left for later.

A more correct non-hacky alternative if any alignment issues are still found
would be to use a compiler specific alignment declaration on the structure and
determine which value to use at configure time.
2012-12-10 18:05:05 -08:00
Antoine Pitrou f9d0b1256f Issue #13390: New function :func:`sys.getallocatedblocks()` returns the number of memory blocks currently allocated.
Also, the ``-R`` option to regrtest uses this function to guard against memory allocation leaks.
2012-12-09 14:28:26 +01:00
Antoine Pitrou ca8aa4acf6 Issue #15144: Fix possible integer overflow when handling pointers as integer values, by using Py_uintptr_t instead of size_t.
Patch by Serhiy Storchaka.
2012-09-20 20:56:47 +02:00
David Malcolm 49526f48fc Issue #14785: Add sys._debugmallocstats() to help debug low-level memory allocation issues 2012-06-22 14:55:41 -04:00
Antoine Pitrou 23683ef26d Issue #10333: Remove ancient GC API, which has been deprecated since
Python 2.2.
2011-01-04 00:00:31 +00:00
Martin v. Löwis 4d0d471a80 Merge branches/pep-0384. 2010-12-03 20:14:31 +00:00
Antoine Pitrou f95a1b3c53 Recorded merge of revisions 81029 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk

........
  r81029 | antoine.pitrou | 2010-05-09 16:46:46 +0200 (dim., 09 mai 2010) | 3 lines

  Untabify C files. Will watch buildbots.
........
2010-05-09 15:52:27 +00:00
Kristján Valur Jónsson ae4cfb1bb3 http://bugs.python.org/issue6836
Merging revisions 75103,75104 from trunk to py3k
2009-09-28 13:45:02 +00:00
Antoine Pitrou 3a652b1d0a Merged revisions 70546 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk

........
  r70546 | antoine.pitrou | 2009-03-23 19:41:45 +0100 (lun., 23 mars 2009) | 9 lines

  Issue #4688: Add a heuristic so that tuples and dicts containing only
  untrackable objects are not tracked by the garbage collector. This can
  reduce the size of collections and therefore the garbage collection overhead
  on long-running programs, depending on their particular use of datatypes.

  (trivia: this makes the "binary_trees" benchmark from the Computer Language
  Shootout 40% faster)
........
2009-03-23 18:52:06 +00:00
Christian Heimes 90aa7646af #1629: Renamed Py_Size, Py_Type and Py_Refcnt to Py_SIZE, Py_TYPE and Py_REFCNT. 2007-12-19 02:45:37 +00:00
Neal Norwitz 30d1c51ac9 Remove _PyObject_Del 2007-08-19 22:48:23 +00:00
Martin v. Löwis 9f2e346911 Merged revisions 56467-56482 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/branches/p3yk

................
  r56477 | martin.v.loewis | 2007-07-21 09:04:38 +0200 (Sa, 21 Jul 2007) | 11 lines

  Merged revisions 56466-56476 via svnmerge from
  svn+ssh://pythondev@svn.python.org/python/trunk

  ........
    r56476 | martin.v.loewis | 2007-07-21 08:55:02 +0200 (Sa, 21 Jul 2007) | 4 lines

    PEP 3123: Provide forward compatibility with Python 3.0, while keeping
    backwards compatibility. Add Py_Refcnt, Py_Type, Py_Size, and
    PyVarObject_HEAD_INIT.
  ........
................
  r56478 | martin.v.loewis | 2007-07-21 09:47:23 +0200 (Sa, 21 Jul 2007) | 2 lines

  PEP 3123: Use proper C inheritance for PyObject.
................
  r56479 | martin.v.loewis | 2007-07-21 10:06:55 +0200 (Sa, 21 Jul 2007) | 3 lines

  Add longintrepr.h to Python.h, so that the compiler can
  see that PyFalse is really some kind of PyObject*.
................
  r56480 | martin.v.loewis | 2007-07-21 10:47:18 +0200 (Sa, 21 Jul 2007) | 2 lines

  Qualify SHIFT, MASK, BASE.
................
  r56482 | martin.v.loewis | 2007-07-21 19:10:57 +0200 (Sa, 21 Jul 2007) | 2 lines

  Correctly refer to _ob_next.
................
2007-07-21 17:22:18 +00:00
Guido van Rossum 3cf5b1eef9 Get rid of most of the flags (in tp_flags) that keep track of various
variations of the type struct and its attachments.  In Py3k, all type
structs have to have all fields -- no binary backwards compatibility.
Had to change the complex object to a new-style number!
2006-07-27 21:53:35 +00:00
Thomas Wouters 49fd7fa443 Merge p3yk branch with the trunk up to revision 45595. This breaks a fair
number of tests, all because of the codecs/_multibytecodecs issue described
here (it's not a Py3K issue, just something Py3K discovers):
http://mail.python.org/pipermail/python-dev/2006-April/064051.html

Hye-Shik Chang promised to look for a fix, so no need to fix it here. The
tests that are expected to break are:

test_codecencodings_cn
test_codecencodings_hk
test_codecencodings_jp
test_codecencodings_kr
test_codecencodings_tw
test_codecs
test_multibytecodec

This merge fixes an actual test failure (test_weakref) in this branch,
though, so I believe merging is the right thing to do anyway.
2006-04-21 10:40:58 +00:00
Neal Norwitz 7b216c52e4 Make PyGC_Collect() use Py_ssize_t. 2006-03-04 20:01:53 +00:00
Martin v. Löwis 6db0e00d57 Change GC refcount to Py_ssize_t. 2006-03-01 16:56:25 +00:00
Martin v. Löwis 41290685f9 Change _PyObject_GC_Resize to expect Py_ssize_t. 2006-02-16 14:56:14 +00:00
Martin v. Löwis 18e165558b Merge ssize_t branch. 2006-02-15 17:27:45 +00:00
Barry Warsaw b941825fa2 Fix PyGC_Collect() to be exported from the built DLL on Windows. (Fix given
by Matt Messier).
2006-01-26 18:59:06 +00:00
Georg Brandl 08c02dbb85 [ 1243081 ] repair typos 2005-07-22 18:39:19 +00:00
Tim Peters eda29306b3 Formalize that the Py_VISIT macro requires that the tp_traverse
implementation it's used in must give its arguments specific names.
2004-07-15 04:05:59 +00:00
Jim Fulton aa6389e13b Documented the new Py_VISIT macro to simplify implementation of
tp_traverse handlers. (Tim made me do it. ;)
2004-07-14 19:08:17 +00:00
Guido van Rossum e13ddc9ec8 - New C API PyGC_Collect(), same as calling gc.collect().
- Call this in Py_Finalize().
- Expand the Misc/NEWS text on PY_LONG_LONG.
2003-04-17 17:29:22 +00:00
Mark Hammond 91a681debf Excise DL_EXPORT from Include.
Thanks to Skip Montanaro and Kalle Svensson for the patches.
2002-08-12 07:21:58 +00:00
Tim Peters 943382c8e5 Removed WITH_CYCLE_GC #ifdef-ery. Holes:
+ I'm not sure what to do about configure.in.  Left it alone.

+ Ditto pyexpat.c.  Fred or Martin will know what to do.
2002-07-07 03:59:34 +00:00
Tim Peters 6fc13d9595 Finished transitioning to using gc_refs to track gc objects' states.
This was mostly a matter of adding comments and light code rearrangement.
Upon untracking, gc_next is still set to NULL.  It's a cheap way to
provoke memory faults if calling code is insane.  It's also used in some
way by the trashcan mechanism.
2002-07-02 18:12:35 +00:00
Tim Peters ea405639bf Reserved another gc_refs value for untracked objects. Every live gc
object should now have a well-defined gc_refs value, with clear transitions
among gc_refs states.  As a result, none of the visit_XYZ traversal
callbacks need to check IS_TRACKED() anymore, and those tests were removed.
(They were already looking for objects with specific gc_refs states, and
the gc_refs state of an untracked object can no longer match any other
gc_refs state by accident.)
Added more asserts.
I expect that the gc_next == NULL indicator for an untracked object is
now redundant and can also be removed, but I ran out of time for this.
2002-07-02 00:52:30 +00:00
Neil Schemenauer b1094f0b1b _PyGC_generation0 is now a pointer 2002-05-04 05:36:06 +00:00
Tim Peters 8b078f95e0 Moving pymalloc along.
As threatened, PyMem_{Free, FREE} also invoke the object deallocator now
when pymalloc is enabled (well, it does when pymalloc isn't enabled too,
but in that case "the object deallocator" is plain free()).

This is maximally backward-compatible, but it leaves a bitter aftertaste.

Also massive reworking of comments.
2002-04-28 04:11:46 +00:00
Tim Peters 0e871188e8 _PyObject_DebugDumpStats: renamed to _PyObject_DebugMallocStats.
Added code to call this when PYMALLOC_DEBUG is enabled, and envar
PYTHONMALLOCSTATS is set, whenever a new arena is obtained and once
late in the Python shutdown process.
2002-04-13 08:29:14 +00:00
Tim Peters e9e7452505 First cut at repairing out-of-date comments; make alignment of macro defs
all the same within the #ifdef WITH_PYMALLOC block.
2002-04-12 05:21:34 +00:00
Neil Schemenauer 3e7b893899 Remove PyMalloc_* symbols. PyObject_Malloc now uses pymalloc if
it's enabled.

Allow PyObject_Del, PyObject_Free, and PyObject_GC_Del to be used as
function designators.  Provide source compatibility macros.

Make PyObject_GC_Track and PyObject_GC_UnTrack functions instead of
trivial macros wrapping functions.
2002-04-12 02:38:45 +00:00
Neil Schemenauer ef99723b66 Add _Py_AS_GC macro. It will be used by the trashcan code on object.c. 2002-03-28 21:06:16 +00:00
Neil Schemenauer ffd5399728 Make PyObject_{NEW,New,Del,DEL} always use the standard malloc (PyMem_*)
and not pymalloc.  Add the functions PyMalloc_New, PyMalloc_NewVar, and
PyMalloc_Del that will use pymalloc if it's enabled.   If pymalloc is
not enabled then they use the standard malloc (PyMem_*).
2002-03-22 15:25:18 +00:00
Neil Schemenauer 25f3dc21b5 Drop the PyCore_* memory API. 2002-03-18 21:06:21 +00:00
Neil Schemenauer 11f5be8d88 Simpilify PyCore_* macros by assuming the function prototypes for
malloc() and free() don't change.
2002-03-18 18:13:41 +00:00
Tim Peters 5e67cded40 PyGC_Head: Use "long double" instead of "double" as the worst-case
alignment gimmick.  David Abrahams notes that the standard "long double"
actually requires stricter alignment than "double" on some Tru64 box.
On my box and yours <wink>, it's the same, so no harm done on most
boxes.
2002-02-28 19:38:51 +00:00
Tim Peters 9e4ca10ce4 SF bug [#467145] Python 2.2a4 build problem on HPUX 11.0.
The platform requires 8-byte alignment for doubles, but the GC header
was 12 bytes and that threw off the natural alignment of the double
members of a subtype of complex.  The fix puts the GC header into a
union with a double as the other member, to force no-looser-than
double alignment of GC headers.  On boxes that require 8-byte alignment
for doubles, this may add pad bytes to the GC header accordingly; ditto
for platforms that *prefer* 8-byte alignment for doubles.  On platforms
that don't care, it shouldn't change the memory layout (because the
size of the old GC header is certainly greater than the size of a double
on all platforms, so unioning with a double shouldn't change size or
alignment on such boxes).
2001-10-11 18:31:31 +00:00
Tim Peters f2a67daca2 Guido suggests, and I agree, to insist that SIZEOF_VOID_P be a power of 2.
This simplifies the rounding in _PyObject_VAR_SIZE, allows to restore the
pre-rounding calling sequence, and allows some nice little simplifications
in its callers.  I'm still making it return a size_t, though.
2001-10-07 03:54:51 +00:00
Tim Peters 6d483d3477 _PyObject_VAR_SIZE: always round up to a multiple-of-pointer-size value.
As Guido suggested, this makes the new subclassing code substantially
simpler.  But the mechanics of doing it w/ C macro semantics are a mess,
and _PyObject_VAR_SIZE has a new calling sequence now.

Question:  The PyObject_NEW_VAR macro appears to be part of the public API.
Regardless of what it expands to, the notion that it has to round up the
memory it allocates is new, and extensions containing the old
PyObject_NEW_VAR macro expansion (which was embedded in the
PyObject_NEW_VAR expansion) won't do this rounding.  But the rounding
isn't actually *needed* except for new-style instances with dict pointers
after a variable-length blob of embedded data.  So my guess is that we do
not need to bump the API version for this (as the rounding isn't needed
for anything an extension can do unless it's recompiled anyway).  What's
your guess?
2001-10-06 21:27:34 +00:00
Tim Peters 406fe3b1c0 Repaired the debug Windows deaths in test_descr, by allocating enough
pad memory to properly align the __dict__ pointer in all cases.

gcmodule.c/objimpl.h, _PyObject_GC_Malloc:
+ Added a "padding" argument so that this flavor of malloc can allocate
  enough bytes for alignment padding (it can't know this is needed, but
  its callers do).

typeobject.c, PyType_GenericAlloc:
+ Allocated enough bytes to align the __dict__ pointer.
+ Sped and simplified the round-up-to-PTRSIZE logic.
+ Added blank lines so I could parse the if/else blocks <0.7 wink>.
2001-10-06 19:04:01 +00:00
Guido van Rossum 048eb75c2d Add Garbage Collection support to new-style classes (not yet to their
instances).

Also added GC support to various auxiliary types: super, property,
descriptors, wrappers, dictproxy.  (Only type objects have a tp_clear
field; the other types are.)

One change was necessary to the GC infrastructure.  We have statically
allocated type objects that don't have a GC header (and can't easily
be given one) and heap-allocated type objects that do have a GC
header.  Giving these different metatypes would be really ugly: I
tried, and I had to modify pickle.py, cPickle.c, copy.py, add a new
invent a new name for the new metatype and make it a built-in, change
affected tests...  In short, a mess.  So instead, we add a new type
slot tp_is_gc, which is a simple Boolean function that determines
whether a particular instance has GC headers or not.  This slot is
only relevant for types that have the (new) GC flag bit set.  If the
tp_is_gc slot is NULL (by far the most common case), all instances of
the type are deemed to have GC headers.  This slot is called by the
PyObject_IS_GC() macro (which is only used twice, both times in
gcmodule.c).

I also changed the extern declarations for a bunch of GC-related
functions (_PyObject_GC_Del etc.): these always exist but objimpl.h
only declared them when WITH_CYCLE_GC was defined, but I needed to be
able to reference them without #ifdefs.  (When WITH_CYCLE_GC is not
defined, they do the same as their non-GC counterparts anyway.)
2001-10-02 21:24:57 +00:00
Neil Schemenauer 49417e76d5 Fix the names of _PyObject_GC_TRACK and _PyObject_GC_UNTRACK when the GC is
disabled.  Obviously everyone enables the GC. :-)
2001-09-03 15:44:48 +00:00
Neil Schemenauer 74b5ade6b8 Change the GC type flag since the API has changed. Allow types using
the old flag to still compile.  Remove the PyType_BASICSIZE and
PyType_SET_BASICSIZE macros.  Add PyObject_GC_New, PyObject_GC_NewVar,
PyObject_GC_Resize, PyObject_GC_Del, PyObject_GC_Track,
PyObject_GC_UnTrack.  Part of SF patch #421893.
2001-08-29 23:49:28 +00:00
Jack Jansen 5756ee0fe6 Removed duplicate definnitions of PyObject_AS_GC and PyObject_FROM_GC (occurred only if GC was off). 2001-08-03 13:03:24 +00:00
Tim Peters 6d6c1a35e0 Merge of descr-branch back into trunk. 2001-08-02 04:15:00 +00:00
Fred Drake 4e262a9631 A small change to the C API for weakly-referencable types: Such types
must now initialize the extra field used by the weak-ref machinery to
NULL themselves, to avoid having to require PyObject_INIT() to check
if the type supports weak references and do it there.  This causes less
work to be done for all objects (the type object does not need to be
consulted to check for the Py_TPFLAGS_HAVE_WEAKREFS bit).
2001-03-22 18:26:47 +00:00
Neil Schemenauer a35c688055 Add Vladimir Marangozov's object allocator. It is disabled by default. This
closes SF patch #401229.
2001-02-27 04:45:05 +00:00
Fred Drake 033f31270c Use a type flag to determine the applicability of the tp_weaklistoffset
field.  This should avoid binary incompatibility problems with older modules
that have not been recompiled.
2001-02-02 18:17:30 +00:00
Fred Drake 41deb1efc2 PEP 205, Weak References -- initial checkin. 2001-02-01 05:27:45 +00:00