[vorbis-dev] Re: SIMD instructions

Michael Smith msmith at xiph.org
Sat Feb 8 06:23:35 PST 2003

On Saturday 08 February 2003 14:06, Felix von Leitner wrote:
> Thus spake Monty (xiphmont at xiph.org):
> > You get slightly different rounding.  It doesn't matter one bit
> > (actually... it matters considerably less than one bit).  No aspect of
> > Vorbis for which an arithmetic result is roundoff-sensitive uses
> > floats.
> Why does the vorbis code then set the rouding mode all the time?

For speed. The vorbisfile code doesn't require this (it'll work perfectly if 
you remove it), but it runs (substantially) faster on x86 with this.


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