GNU C library's libmvec and the GNU Compiler *Collection*.

[Toon Moene <toon at moene dot org>]

All,

I noticed, around half a year ago, that the incredible team around glibc 
found the time to implement vector math (libm) routines.

Previously, free software adherents like me were dependent on vendor 
libraries via the -mveclibabi={svml|acml} (on Intel/AMD) for instance.

However, the examples given on the glibc wiki 
(https://sourceware.org/glibc/wiki/libmvec, Example 1/Example 2) suggest 
that this is a C-only thing (this might make sense given that glibc is 
an implementation of the *C* library), but the above vendor-level 
options at least work for every front-end language, as far as I know.

Would it be possible to add an option -mveclibabi=glibc to cater for 
this *for all languages*; or is this too low level (after all, the glibc 
libmvec has code for multiple architectures). If so, at what level 
should this be implemented ?

[ This is relevant for our code, because just the switch to *actual*
  single precision exp/log/sin/cos implementations in glibc's libm
  resulted in a decrease of the running time of our weather forecasting
  code by 25 % (this was in glibc 2.16, IIRC). ]

Thanks in advance for your suggestions.

--
Toon Moene - e-mail: toon@moene.org - phone: +31 346 214290
Saturnushof 14, 3738 XG  Maartensdijk, The Netherlands
At home: http://moene.org/~toon/; weather: http://moene.org/~hirlam/
Progress of GNU Fortran: http://gcc.gnu.org/wiki/GFortran#news