#include <mach/mach_time.h>
#define GET_START() mach_absolute_time()
#define GET_DURATION(start, info) ((mach_absolute_time() - start) * info.numer)/info.denom
#include <mach/mach_time.h>
#define GET_START() mach_absolute_time()
#define GET_DURATION(start, info) ((mach_absolute_time() - start) * info.numer)/info.denom