This is the mail archive of the gcc-help@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

How to get a vector FMA with GCC in a portable way?


I would like to know how to get a vector FMA with GCC in a portable
way.

By "portable way", I mean that the behavior must not depend on the
compilation options (e.g., if FP contraction is disabled, I still
want a true FMA) and that the code must not depend on the architecture
(thus intrinsics should not be used... even when restricting to x86,
one reason is FMA3 vs FMA4 issues).

For instance, for addition, one can write "a + b". But for FMA?

Thanks,

-- 
Vincent Lefèvre <vincent@vinc17.net> - Web: <https://www.vinc17.net/>
100% accessible validated (X)HTML - Blog: <https://www.vinc17.net/blog/>
Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]