The "__i386__" preproc definition tells me that the compiler is
compiling for an IA32 CPU, and it will accept MMX instructions, so I can
put them in. Before calling any of the MMX routines, I've called a
SDL_cpuinfo function which tells me whether or not the currently running
CPU supports MMX, so if someone were to run this on a 486 or non-MMX
Pentium, it won't call the MMX functions.
Unfortunately, Luke, most Windows folks will be running the C routines
and not get the benefit of MMX because I've written the inline ASM in
AT&T-style syntax which is not supported by Visual Studio. If a Windows
user compiles with GCC, however (with MinGW? or Cygwin), they will get
the MMX code.
Richard
Marcus von Appen wrote:
> On, Sat Jun 23, 2007, Luke Paireepinart wrote:
>
>> Christopher Arndt wrote:
>>> Charles Joseph Christie II schrieb:
>>>
>>>> If I remember correctly, i486 introduced MMX.
>>>>
>>> No, that was the Pentium MMX, an improved version of the Pentium I (i586).
>>>
>> Okay, so then I don't understand how __i386__ helps us.... does it tell us
>> that the cpu doesn't support MMX?
>
> No, it just tells us, that the CPU is likely to be an intel-conpliant
> one.
>
> Regards
> Marcus