On Sep 11, 2009, at 8:00 AM, Lisandro Dalcin wrote:
> What about implementing Pyx_PyNumber_Int in such a way that we can be
> sure that it returns a EXACT PyInt/PyLong (or NULL in case of failure)
> ? Then we could safely use CheckExact in the other conversor functions
> (and perhaps a "goto begin" in order to avoid the recursion?)
Well, it could be more expensive to construct the new object if all
we want to do is extract out the long value. Also, I'm worried that
Pyx_PyNumber_Int checks for PyInt/PyLong, even if it's only called on
non PyInt/PyLong values. Given that this whole thing gets inlined all
over the place, we also need to be concerned about code size (not for
the .so size, but it can make a difference for instruction caches).
Note that I pushed your #333, though we can continue working on top
of it.
- Robert
>
>
> On Wed, Sep 9, 2009 at 5:58 AM, Robert Bradshaw
> <rober...@math.washington.edu> wrote:
>> On Jun 19, 2009, at 9:44 AM, Lisandro Dalcin wrote:
>>
>>> I've finally managed to write a more or less working patch...
>>> Look at
>>> the test, I've tried to cover many corner cases...
>>>
>>> 1) Dag & Kurt: I bet you will be happy.
>>>
>>>
>>> 2) Robert: your eyeballs needed, please comment on this:
>>>
>>> a) Look at the changes outside PyrexTypes.pyx, I believe they make
>>> sense, though I would like you to confirm that.
>>>
>>> b) In the past, you raised some concerns about __int32 from ILP64
>>> model... A possible (and suboptimal, no overflow-safe) way of
>>> handling
>>> that is there, though "#if 0" disabled. I've tried to take advantage
>>> of "_PyLong_{As/From}ByteArray()", but that (in particular, the "As"
>>> one) is somewhat harder to use, as we should pass a PyLongObject
>>> type.
>>
>> Sorry I've taken so long to get back on this. I have read all the
>> code, and it looks good. I've posted some comments on trac. http://
>> trac.cython.org/cython_trac/ticket/333
>>
>> - Robert
>>
>> _______________________________________________
>> Cython-dev mailing list
>> Cython-dev@codespeak.net
>> http://codespeak.net/mailman/listinfo/cython-dev
>>
>
>
>
> --
> Lisandro Dalcín
> ---------------
> Centro Internacional de Métodos Computacionales en Ingeniería (CIMEC)
> Instituto de Desarrollo Tecnológico para la Industria Química (INTEC)
> Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)
> PTLC - Güemes 3450, (3000) Santa Fe, Argentina
> Tel/Fax: +54-(0)342-451.1594
> _______________________________________________
> Cython-dev mailing list
> Cython-dev@codespeak.net
> http://codespeak.net/mailman/listinfo/cython-dev
_______________________________________________
Cython-dev mailing list
Cython-dev@codespeak.net
http://codespeak.net/mailman/listinfo/cython-dev
