[Bug libstdc++/11706] std::pow(T, int) implementation pessimizes code

["rguenth at tat dot physik dot uni-tuebingen dot de" <gcc-bugzilla at gcc dot gnu dot org>]

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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11706



------- Additional Comments From rguenth at tat dot physik dot uni-tuebingen dot de  2003-09-29 14:29 -------
Subject: Re:  std::pow(T, int) implementation pessimizes
 code

On 29 Jul 2003, gdr at integrable-solutions dot net wrote:

> "steven at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org> writes:
>
> | Or are there reasons bigger than us that prevent such an implementation from
> | being correct?
>
> The expansion of pow() as an inline function may be quite large and
> have negative impact on the overall program.  That is why it does not
> suffice to examine the assembler output nor just a single (kind) of
> application -- be it scientific.
>
> This is not meant to dismiss the report.  I'll take care of it.

Any progress on this? I still think this is a show stopper. What about the
suggested replacement of the __pow_helper() with ::pow() which is now
optimized by an appropriate builtin?

Thanks,

Richard.

--
Richard Guenther <richard dot guenther at uni-tuebingen dot de>
WWW: http://www.tat.physik.uni-tuebingen.de/~rguenth/