Intel® C++ Compiler
Community support and assistance for creating C++ code that runs on platforms based on Intel® processors.
7956 Discussions

using FMA intrinsics

bronxzv
New Contributor II
‎02-16-2011 08:02 AM
368 Views
intrinsics for FMA AVX instructions are well explained in theC++ Composer XE 2011 documentation

Intrinsics Reference -> Intrinsics for Intel Advanced Vector Extensions -> Intrinsics for Fused Multiply Add Operations

though these intrinsics are missing in "immintrin.h" and all other such headers apparently, thus a simple question :how can we use these intrinsics ? (a compile flag ? other ?)
0 Kudos

Link Copied

2 Replies
TimP
Honored Contributor III
‎02-16-2011 10:04 AM
368 Views
There's no AVX FMA support in current released Intel compilers, so it's strange to see them described in the documentation. Such compilers haven't even reached beta. There's fma support in beta gcc, I believe.
0 Kudos
Copy link
bronxzv
New Contributor II
‎02-16-2011 11:54 AM
368 Views
thanks for the information, though it looks rather odd since there is more than 20 pages in the user manual detailing FMA intrinsics
0 Kudos
Copy link
Reply

Community support is provided during standard business hours (Monday to Friday 7AM - 5PM PST). Other contact methods are available here.

Intel does not verify all solutions, including but not limited to any file transfers that may appear in this community. Accordingly, Intel disclaims all express and implied warranties, including without limitation, the implied warranties of merchantability, fitness for a particular purpose, and non-infringement, as well as any warranty arising from course of performance, course of dealing, or usage in trade.

For more complete information about compiler optimizations, see our Optimization Notice.