serval-dna/nacl/nacl-20110221/cpucycles/amd64tscfreq.c

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#include <stdio.h>
#include <sys/types.h>
long long cpucycles_amd64tscfreq(void)
{
unsigned long long result;
asm volatile(".byte 15;.byte 49;shlq $32,%%rdx;orq %%rdx,%%rax"
: "=a" (result) :: "%rdx");
return result;
}
long long cpucycles_amd64tscfreq_persecond(void)
{
long result = 0;
size_t resultlen = sizeof(long);
sysctlbyname("machdep.tsc_freq",&result,&resultlen,0,0);
return result;
}