Newsgroups: comp.os.msdos.djgpp
From: Peter Berdeklis <peter AT atmosp DOT physics DOT utoronto DOT ca>
Subject: Re: MMX 
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Date: Fri, 7 Mar 1997 18:38:25 GMT
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To: djgpp AT delorie DOT com
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On Tue, 4 Mar 1997, Salvador Eduardo Tropea (SET) wrote:
> * If you want to use MMX at 100%, you must make one of 2 things:
> A) Make a very specialized optimizer, is really hard.
> B) Make an extention of the C language, but will be totally non-standard.
> 
[snip]
>   
>   If somebody makes that in the (B) fashion the best way is the use of 
> #pragmas but even with that is very hard because the compiler must see the 
> parallel operations and how to pack it in parallel MMX operations, plus the 
> fact that Intel is using FPU registers for that ... 

If these extensions to C are written they would likely be written in hand
coded/massaged inline asm.  In that case the compiler doesn't need to know
anything about packing and parallel op's, just which registers are 
invalid (eg. the whole FPU stack).

---------------
Peter Berdeklis
Dept. of Physics, Univ. of Toronto