* Bernhard Praschinger on Thursday, October 14, 2010 at 19:06:33 +0200
>> Oh yeah, this isn't on Linux.  OSX probably has some kind of API for
>> checking if sse2 is available.  Using CPUID isn't enough, because sse
>> requires OS support that might not be there.  I.e., the cpu supports
>> sse2 but you're not actually able to use it.  Probably not much of issue
>> on OSX.
>> 
>> Easy fix would just be the change the sse detection asm to save and
>> restore ebx.
>> 
>> __asm__ volatile("pushl %%ebx ; cpuid ; popl %%ebx" : "=d"(d) : "a"(1) :
>> "ecx");
>> 
>> or better
>> 
>> uint32_t tmp;
>> __asm__ volatile("movl %%ebx, %1; cpuid; movl %1, %%ebx" : "=d"(d),
>> "=&g"(tmp) : "a"(1) : "ecx");
>> 
>> The latter is safer in general, as you can't use push or pop around any
>> asm code that has a parameter with a constraint that allows memory
>> references.  The memory reference might be relative to esp, in which
>> case the push/pop would move it.  Or it might not be relative to esp, in
>> which case the push/pop doesn't move it.  So there's no way to adjust
>> for it.
> I tested your better version. And it compiles here on my linux and Intel 
> osx box. I did also a quick test with the new version on the linux box. 
> And it works well.
> 
> So I would appreciate a feedback if it works on a mac.

Thanks for looking into this, but I get:

gcc -DHAVE_CONFIG_H -I. -I.. -I.. -I../utils   -O3 -funroll-all-loops 
-ffast-math -march=nocona -mtune=nocona -g -O2 -I/sw/include -no-cpp-precomp 
-D_THREAD_SAFE  -Wall -Wunused -MT main.o -MD -MP -MF .deps/main.Tpo -c -o 
main.o main.c
main.c: In function ‘main’:
main.c:1339: error: PIC register ‘ebx’ clobbered in ‘asm’
make: *** [main.o] Error 1

$ sw_vers
ProductName:    Mac OS X
ProductVersion: 10.5.8
BuildVersion:   9L30

c
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