On Feb 27, 2009, at 12:23 AM, Robert Bradshaw wrote:
> On Feb 27, 2009, at 12:18 AM, Stefan Behnel wrote:
>
>> Robert Bradshaw wrote:
>>> On Feb 26, 2009, at 11:41 PM, Stefan Behnel wrote:
>>>> I'd like to also optimise negative indices (at least -1 is
>>>> extremely
>>>> common),
>>>> that'll definitely make the List/Tuple functions too long for
>>>> their minor
>>>> differences.
>>>
>>> Good idea, doing that right now.
>>
>> What about this? I checked the assembly, and it looks not too
>> bloated to me.
>>
>> Stefan
>>
>>
>> static INLINE PyObject *__Pyx_GetItemInt_%(type)s(PyObject *o,
>> Py_ssize_t
>> i, int is_unsigned) {
>> if (likely(o != Py_None)) {
>> if (likely((i < Py%(type)s_GET_SIZE(o)) &
>> (i >= -Py%(type)s_GET_SIZE(o)))) {
>> if (unlikely(i < 0))
>> i = Py%(type)s_GET_SIZE(o) + i;
>> PyObject *r = Py%(type)s_GET_ITEM(o, i);
>> Py_INCREF(r);
>> return r;
>> }
>> }
>> return __Pyx_GetItemInt_Generic(o, i, is_unsigned);
>> }
>
> This doesn't handle i < -len(o).
Never-mind, didn't read carefully enough.
Another optimization I'd like to do is not increfing the result. Then
it could even be used in a nogil context (maybe?). Somehow, we'd have
to know the reference was borrowed though, which will be a bit more
invasive.
- Robert
_______________________________________________
Cython-dev mailing list
[email protected]
http://codespeak.net/mailman/listinfo/cython-dev
