Re: adding attributes

[Dave Love <dave.love@manchester.ac.uk>]

Thomas Koenig via Fortran <fortran@gcc.gnu.org> writes:

> Hi Bernhard,
>
>> If you think that we want to add support for that attribute, i can
>> submit a proper patch. Just let me know please.
>
> I think this attribute makes sense, especially if people want to
> compile once and then port to different architectures.
>
> So, yes please submit a patch, if you would be so kind :-)
>
> Best regards
>
> 	Thomas

I'll make a list of others I think would be useful for consideration.  I
should probably have looked at what similar facilities proprietary
compilers provide.

I should say the intent of optimization-related attributes would be to
encourage adding them to known performance-sensitive kernels, and
potentially avoid having to write C.  However, I doubt I can persuade
the people who are convinced of the great superiority of ifort, and the
desirability of always adding -axCORE-AVX512, without measuring or
understanding GCC options.

I think an equivalent of "#pragma GCC optimize" could be useful too.  I
don't have a specific case in mind, but an example might be where you
need localized standard-conforming arithmetic, but other parts of the
program benefit from -ffast-math.