Shortly after I responded to the two responses to my posting, I
randomly, unintentionally, fell upon new information directly related to
this.

In the Pentium II Deschutes series of processors (P2-333 and up), there
are two new semi-undocumented instructions.  These instructions are
primarly meant to be real and documented (people in the know believe...)
when the MMX2/KNI processors come out (which are the Katmai series).

The instructions are FXSAVE and FXRSTOR, which do the same basic
function as FSAVE and FRSTOR, except "faster".  Apparently this is
primarily targeted at OS vendors, to speed up FPU state switching when
task switching.... but they are also here to make this state switching
faster for software which makes use of MMX or (sometime soon..) MMX2
instructions.

The presence of the semi-undocmented instructions can be accurately
detected via CPUID.

Here's a link to the site I found this on:

http://www.tbcnet.com/~clive

Look around there for the word "Deschutes".

Given these instructions... that lowers the major barriers to one last
biggy:  Finding some intense non-FP math to accelerate in povray :)

Just htought someone might be interested in this stuff anyways, since we
were discussing it though...

Brandon

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