[speex-dev] Notes on 1.1.4 Windows. Testing of SSE Intrinics Code and others

[Aron Rosenberg]

Reading through the GCC manual seems to imply that using -msse allows the 
intrinsics to be available for use. It does not make any other code use the 
SSE registers or calls.

http://gcc.gnu.org/onlinedocs/gcc-3.3.2/gcc/i386-and-x86-64-Options.html#i386%20and%20x86-64%20Options 
(scroll down to the -msse section)

-mmmx -mno-mmx-msse -mno-sse -msse2 -mno-sse2 -m3dnow -mno-3dnow
These switches enable or disable the use of built-in functions that allow 
direct access to the MMX, SSE and 3Dnow extensions of the instruction set.
See 
<http://gcc.gnu.org/onlinedocs/gcc-3.3.2/gcc/X86-Built-in-Functions.html#X86%20Built-in%20Functions>X86 
Built-in Functions, for details of the functions enabled and disabled by 
these switches.
To have SSE/SSE2 instructions generated automatically from floating-point 
code, see -mfpmath=sse.

This would seem to be the proper flag assuming that the code or all 
entry-ways into it is guarded by run-time flags.

Aron Rosenberg
SightSpeed

At 12:48 AM 1/22/2004, you wrote:
> >          Are you sure that you don't need to add just -msse to enable the
> > intrinsics rather than a full fledged -march=pentium3? I did some playing
> > around and I can get intrinsics code to compile with -march=i686  -msse on
> > linux with that.
>
>I'll have a closer look at that, but I'm not sure it'll do the job. If
>-msse allows the compiler to generate sse instructions, then it won't
>work with older processors.
>
>         Jean-Marc
>
>--
>Jean-Marc Valin, M.Sc.A., ing. jr.
>LABORIUS (http://www.gel.usherb.ca/laborius)
>Université de Sherbrooke, Québec, Canada

<p><p>--- >8 ----
List archives:  http://www.xiph.org/archives/
Ogg project homepage: http://www.xiph.org/ogg/
To unsubscribe from this list, send a message to 'speex-dev-request at xiph.org'
containing only the word 'unsubscribe' in the body.  No subject is needed.
Unsubscribe messages sent to the list will be ignored/filtered.