[ODE] timer.cpp portability (was Re: building on intel OSX)

[Tanguy Fautre]

Hampus Soderstrom wrote:
> Hi,
> 
> Here is a patch to get timer.cpp to compile on Intel OS X.
> 
> RCS file: /cvsroot/opende/ode/ode/src/timer.cpp,v
> retrieving revision 1.11.2.2
> diff -r1.11.2.2 timer.cpp
> 128c128
> <       "mov $0,%%eax\n"
> ---
>  >       "mov %%ebx,%%edi\n"
> 130c130
> <       : : : "%eax","%ebx","%ecx","%edx","cc","memory");
> ---
>  >       : : : "%eax","%edi","%ecx","%edx","cc","memory");
> 
> 


How about using something a little more portable (cf. following piece of 
code) ?

That's what I use for our projects. It works on both x86 and x86_64, 
Linux, Windows (VC++ 6.0, 7.0, 7.1, 8.0), and QNX.

Also, note how the GCC path seems more portable that ODE current code 
for RDTSC.

Tanguy




#ifndef HEADER_GUARD_TIMER_X86_RDTSC_H
#define HEADER_GUARD_TIMER_X86_RDTSC_H

// Visual C++ 8.0 has a __rdtsc() intrinsic
#if ((defined _MSC_VER) && (_MSC_VER > 1310))
#include <intrin.h>
#endif

#if defined __QNX__
#include <sys/neutrino.h>
#endif



namespace timer
{

	uint64_t x86_rdtsc();

}





namespace timer {



inline uint64_t x86_rdtsc()
{

// Visual C++ 8.0 has a __rdtsc() intrinsic
#if ((defined _MSC_VER) && (_MSC_VER > 1310))

	return __rdtsc();

// Visual C++ 7.1 or lower have to use inline assembly
#elif (defined _MSC_VER) && (_MSC_VER <= 1310)

	__asm
	{
		rdtsc
	}

// QNX supports a more portable call: ClockCycles()
#elif defined __QNX__

	return ClockCycles();

// GCC supports "portable" assembly for both x86 and x86_64
#elif defined __GNUC__

	volatile uint32_t Low, High;
	
	asm volatile ("rdtsc" : "=a" (Low), "=d" (High));
	
	return (uint64_t(High) << 32) + Low;

// RDTSC not supported
#elif

	return 0;

#endif

}



} // namespace timer



#endif // HEADER_GUARD_TIMER_X86_RDTSC_H