diff options
Diffstat (limited to 'Objects')
| -rw-r--r-- | Objects/listobject.c | 19 |
1 files changed, 11 insertions, 8 deletions
diff --git a/Objects/listobject.c b/Objects/listobject.c index 996ddb9..1fb77b9 100644 --- a/Objects/listobject.c +++ b/Objects/listobject.c @@ -25,13 +25,14 @@ static int list_resize(PyListObject *self, int newsize) { PyObject **items; - size_t _new_size; + size_t new_allocated; + int allocated = self->allocated; /* Bypass realloc() when a previous overallocation is large enough - to accommodate the newsize. If the newsize is 16 smaller than the - current size, then proceed with the realloc() to shrink the list. + to accommodate the newsize. If the newsize falls lower than half + the allocated size, then proceed with the realloc() to shrink the list. */ - if (self->allocated >= newsize && self->ob_size < newsize + 16) { + if (allocated >= newsize && newsize >= (allocated >> 1)) { assert(self->ob_item != NULL || newsize == 0); self->ob_size = newsize; return 0; @@ -44,10 +45,12 @@ list_resize(PyListObject *self, int newsize) * system realloc(). * The growth pattern is: 0, 4, 8, 16, 25, 35, 46, 58, 72, 88, ... */ - _new_size = (newsize >> 3) + (self->ob_size < 8 ? 3 : 6) + newsize; + new_allocated = (newsize >> 3) + (newsize < 9 ? 3 : 6) + newsize; + if (newsize == 0) + new_allocated = 0; items = self->ob_item; - if (_new_size <= ((~(size_t)0) / sizeof(PyObject *))) - PyMem_RESIZE(items, PyObject *, _new_size); + if (new_allocated <= ((~(size_t)0) / sizeof(PyObject *))) + PyMem_RESIZE(items, PyObject *, new_allocated); else items = NULL; if (items == NULL) { @@ -56,7 +59,7 @@ list_resize(PyListObject *self, int newsize) } self->ob_item = items; self->ob_size = newsize; - self->allocated = _new_size; + self->allocated = new_allocated; return 0; } |