rdtsc.h

来自「加密认证联合模式的源代码」· C头文件 代码 · 共 39 行

#ifndef RDTSC_H
#define RDTSC_H

#if defined( _MSC_VER )

#if defined( _WIN64 )

#include <intrin.h>
#pragma intrinsic( __rdtsc )
__inline volatile unsigned long long read_tsc(void)
{
    return __rdtsc();
}

#else

__inline volatile unsigned long long read_tsc(void)
{   unsigned long lo, hi;
    __asm cpuid __asm rdtsc __asm mov [lo],eax __asm mov [hi],edx ;
    return (((unsigned long long)hi) << 32) + lo;
}

#endif

#elif defined( __GNUC__ )

__inline volatile unsigned long long read_tsc(void)
{   unsigned long lo, hi;
    asm volatile("cpuid; read_tsc" : "=a" (lo), "=d" (hi));
    return (((unsigned long long)hi) << 32) + lo;
}

#else
#error A high resolution timer is not available
#endif

#endif