> It is also a compiler problem. You didn't say which compiler you used or
> how you got it to produce 3D!Now code. Essentially there are 3
> possibilities:
>
> 1) You have a compiler which can generate 3D!Code out of "natural" C
>     code. This is the ideal case. The same code can be used for 3D!Now
>     platforms and for others.
>
> 2) You have a compiler which can generate 3D!Now code, if the C code
>    follows a certain pattern. This lets you still write portable C code,
>    but it may be arranged unintuitively and therefore hard to maintain
>    and even slower than the "natural" code on other platforms.
>
> 3) You used inline assembly. This is very compiler specific. gcc
>     definitely uses a different syntax than VC++, and what I remember
>     from my DOS programming days, there were differences between MS C
>     and Borland C, too. This means a lot of code duplication: Not only
>     for different processor types, but for different compilers, too.
>
>     So, just to maintain the 4 types of SIMD instructions you mentioned,
>     on the main Intel platforms, you may have to maintain 9 or 13
>     versions of the same code! And not only you have to maintain it, but
>     everybody else who wants to change anything in the affected code.
>     Unless this is very localized, the chances that somebody who wants
>     to implement a new pattern or media type, has to worry about some
>     assembler code he can't even read, seem high to me.

The question is not 1, 2 or 3, the question is for answer 3 you need not
verry mucht time, but answer 1 is also possible, but verry much more work!

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