#include <math.h>
#include <windows.h>
#include <winnt.h>
#include <winbase.h>

#define CPUID __asm __emit 0fh __asm __emit 0a2h
#define RDTSC __asm __emit 0fh __asm __emit 031h

unsigned __int64 readTSC(){
    unsigned cycles_low, cycles_high;
    
    __asm {
        pushad
            CPUID			
            RDTSC
            mov	cycles_high, edx			
            mov	cycles_low, eax	
            popad
				}
    return ((unsigned __int64)cycles_high << 32) | cycles_low;
}