This patch modifies the type structures of objects that
participate in GC. The object's tp_basicsize is increased when
GC is enabled. GC information is prefixed to the object to
maintain binary compatibility. GC objects also define the
tp_flag Py_TPFLAGS_GC.
The following patch adds "sq_contains" support to rangeobject, and enables
the already-written support for sq_contains in listobject and tupleobject.
The rangeobject "contains" code should be a bit more efficient than the
current default "in" implementation ;-) It might not get used much, but it's
not that much to add.
listobject.c and tupleobject.c already had code for sq_contains, and the
proper struct member was set, but the PyType structure was not extended to
include tp_flags, so the object-specific code was not getting called (Go
ahead, test it ;-). I also did this for the immutable_list_type in
listobject.c, eventhough it is probably never used. Symmetry and all that.
For more comments, read the patches@python.org archives.
For documentation read the comments in mymalloc.h and objimpl.h.
(This is not exactly what Vladimir posted to the patches list; I've
made a few changes, and Vladimir sent me a fix in private email for a
problem that only occurs in debug mode. I'm also holding back on his
change to main.c, which seems unnecessary to me.)
Added wrapping macros to dictobject.c, listobject.c, tupleobject.c,
frameobject.c, traceback.c that safely prevends core dumps
on stack overflow. Macros and functions in object.c, object.h.
The method is an "elevator destructor" that turns cascading
deletes into tail recursive behavior when some limit is hit.
diagnostics.
*** INCOMPATIBLE CHANGE: This changes append(), remove(), index(), and
*** count() to require exactly one argument -- previously, multiple
*** arguments were silently assumed to be a tuple.
+ Took the "list" argument out of the other functions that no longer need
it. This speeds things up a little more.
+ Small comment changes in accord with that.
+ Exploited the now-safe ability to cache values in the partitioning loop.
Makes no timing difference on my flavor of Pentium, but this machine ran out
of registers 12 iterations ago. It should yield a small speedup on a RISC
machine, and not hurt in any case.
instead of testing whether the list changed size after each
comparison, temporarily set the type of the list to an immutable list
type. This should allow continued use of the list for legitimate
purposes but disallows all operations that can change it in any way.
(Changes to the internals of list items are not caught, of cause;
that's not possible to detect, and it's not necessary to protect the
sort code, either.)