//----------------------------------------------------
// tas.cc --> https://www.felixcloutier.com/x86/pause
//----------------------------------------------------

#include <atomic>
#include <iostream>
#include <latch>
#include <thread>

//----------------------------------------------------

using namespace std::literals;

//----------------------------------------------------

const size_t N = 32;
std::latch latch(N);
std::atomic<bool> stop = false;

//----------------------------------------------------

template<typename T> T test_and_set(volatile T *spinlock)
{
    T ret = true;
    __asm__ __volatile__("pause; xchg %0, %1" : "+r"(ret), "+m"(*spinlock));
    return ret;
}

//----------------------------------------------------

class cerrojo
{
public:
    void adquirir() { while (test_and_set(&cerrado)); }
    void liberar() { cerrado = false; }

private:
    volatile bool cerrado = false;
} c;

//----------------------------------------------------

void seccion_critica()
{
    std::cout << "[" << std::this_thread::get_id() << "]: ";
    for (size_t i = 0; i < 10; ++i) std::cout << i;
    std::cout << '\n';
}

//----------------------------------------------------

void hebra()
{
    latch.arrive_and_wait();
    while (!stop)
    {
        c.adquirir();
        if (!stop) seccion_critica();
        c.liberar();
    }
}

//----------------------------------------------------

int main()
{
    std::jthread threads[N];

    for (auto &i: threads) i = std::jthread(hebra);

    std::this_thread::sleep_for(75ms);
    stop = true;
}

//----------------------------------------------------