Use Py_VISIT in all tp_traverse methods, instead of traversing manually or
using a custom, nearly-identical macro. This probably changes how some of
these functions are compiled, which may result in fractionally slower (or
faster) execution. Considering the nature of traversal, visiting much of the
address space in unpredictable patterns, I'd argue the code readability and
maintainability is well worth it ;P
diff --git a/Objects/typeobject.c b/Objects/typeobject.c
index a0af2c9..43f0469 100644
--- a/Objects/typeobject.c
+++ b/Objects/typeobject.c
@@ -525,21 +525,15 @@
if (type->tp_dictoffset != base->tp_dictoffset) {
PyObject **dictptr = _PyObject_GetDictPtr(self);
- if (dictptr && *dictptr) {
- int err = visit(*dictptr, arg);
- if (err)
- return err;
- }
+ if (dictptr && *dictptr)
+ Py_VISIT(*dictptr);
}
- if (type->tp_flags & Py_TPFLAGS_HEAPTYPE) {
+ if (type->tp_flags & Py_TPFLAGS_HEAPTYPE)
/* For a heaptype, the instances count as references
to the type. Traverse the type so the collector
can find cycles involving this link. */
- int err = visit((PyObject *)type, arg);
- if (err)
- return err;
- }
+ Py_VISIT(type);
if (basetraverse)
return basetraverse(self, visit, arg);
@@ -2198,32 +2192,21 @@
static int
type_traverse(PyTypeObject *type, visitproc visit, void *arg)
{
- int err;
-
/* Because of type_is_gc(), the collector only calls this
for heaptypes. */
assert(type->tp_flags & Py_TPFLAGS_HEAPTYPE);
-#define VISIT(SLOT) \
- if (SLOT) { \
- err = visit((PyObject *)(SLOT), arg); \
- if (err) \
- return err; \
- }
-
- VISIT(type->tp_dict);
- VISIT(type->tp_cache);
- VISIT(type->tp_mro);
- VISIT(type->tp_bases);
- VISIT(type->tp_base);
+ Py_VISIT(type->tp_dict);
+ Py_VISIT(type->tp_cache);
+ Py_VISIT(type->tp_mro);
+ Py_VISIT(type->tp_bases);
+ Py_VISIT(type->tp_base);
/* There's no need to visit type->tp_subclasses or
((PyHeapTypeObject *)type)->ht_slots, because they can't be involved
in cycles; tp_subclasses is a list of weak references,
and slots is a tuple of strings. */
-#undef VISIT
-
return 0;
}
@@ -5805,20 +5788,10 @@
super_traverse(PyObject *self, visitproc visit, void *arg)
{
superobject *su = (superobject *)self;
- int err;
-#define VISIT(SLOT) \
- if (SLOT) { \
- err = visit((PyObject *)(SLOT), arg); \
- if (err) \
- return err; \
- }
-
- VISIT(su->obj);
- VISIT(su->type);
- VISIT(su->obj_type);
-
-#undef VISIT
+ Py_VISIT(su->obj);
+ Py_VISIT(su->type);
+ Py_VISIT(su->obj_type);
return 0;
}