test.cpp

#include <cstdlib>
#include <iostream>

struct register_
{
    unsigned short low;
    unsigned short high;
};

int main()
{

#define cpuid(code, a, b, c)                                                   \
    asm volatile("cpuid" : "=a"(a), "=b"(b), "=c"(c) : "a"(code) : "edx")

    register_ eax, ebx, ecx;
    cpuid(0x5, eax, ebx, ecx);

    std::cout << "eax[" << eax.high << ", " << eax.low << "]" << std::endl;
    std::cout << "ebx[" << ebx.high << ", " << ebx.low << "]" << std::endl;
    std::cout << "ecx[" << ecx.high << ", " << ecx.low << "]" << std::endl;

    unsigned int monitor_size = eax.low;
    std::cout << "Use size: " << monitor_size << std::endl;

    void* test = malloc(monitor_size);

    std::cout << "monitor:" << std::endl;
    __builtin_ia32_monitor(test, 0, 0);

    std::cout << "wait:" << std::endl;
    __builtin_ia32_mwait(0, 0);

    std::cout << "Exit" << std::endl;
    return 0;
}