Michael Marineau wrote: > Chris White wrote:
Michael Marineau wrote:
What's the point of a use flag if you purposfully use the sse useflag to do something different? this sort of thing would make more sense:
sse = sse's integer logic sse = sse's floating point stuff mmx2 = mmx2
Problem mmx2 = sse (on intel) mmx2 = I don't know what (on amd) mmx2 != mmxext
Weird, so where does this mmx2 name come from then if it's just sse?
Hey. I'm the complaining users. ;]
This has been bugging me so I've been doing some digging, trying to put together some kind of idea of how everything fits. I hope it helps make some sense. Basically, you can see what i came up with in this post.
http://forums.gentoo.org/viewtopic-t-310794.html
I'm a little hazy about the AMD side of it, as I've no experience with them. What I do know for sure is that back in '99, Intel was hyping the new KNI (Katmai New Instructions) instruction set, aka Pentium III. You can see references to it in articles around that time (see forum post). Up until the the actual release of the Katmai these articles often use KNI and MMX2 interchangably. The best source I can find that I trust not to be PR fluff is http://www.tbcnet.com/~clive/katmai.html - where it's stated "The official name for Katmai is Pentium III, what the new opcodes are called is still in the air, is it MMX2, KNI or perhaps XMM?". The name that Intel did finally settle on was Streaming SIMD Extensions - SSE. So, for all intents and purposes MMX2 = SSE.
Now AMD had the 3DNow! instruction set which they introduced with the K6-2 in '98, as a SIMD extension to MMX. SSE/MMX2 was brought in after that by Intel. So MMX2 != AMD and never did. AMD did later integrate SSE into the 3DNow Pro though. So what the hell is MMXExt? I think it's an old name for the original integer instructions extensions the 3DNow made to MMX. That's a very sketchy conclusion though and I wouldn't be surprised to be proven wrong. I can say for certain that it is AMD specific. If you want proof: http://forums.gentoo.org/viewtopic-t-103757.html ;]
As to how to apply all this to MPlayer..
o.O
obl refs- http://en.wikipedia.org/wiki/Streaming_SIMD_Extensions http://en.wikipedia.org/wiki/3DNow%21 http://www.tommesani.com/3DNow.html http://www.intel.com/pressroom/archive/releases/dp022699.htm http://developer.intel.com/design/pentiumii/manuals/245127.htm
r.
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