#include <iostream>
#include <sys/time.h>
#include <random>

using namespace std;

const int SIZE = 256 * 1024 * 1024;
const int pagenum = 16 * 1024;
const int pagesize = SIZE / pagenum;

void xorsum_seq(int *data)
{
    int xorsum = 0;
    timeval start, end;
    gettimeofday(&start, nullptr);
    for (int page = 0; page < pagenum; page++)
    {
        for (int idx = 0; idx < pagesize; idx++)
            xorsum ^= data[page * pagesize + idx];
    }

    gettimeofday(&end, nullptr);
    double usec = (end.tv_sec - start.tv_sec) + (double)(end.tv_usec - start.tv_usec) / 1000000;
    cout << __func__ << " duration: " << usec << ", xorsum: " << xorsum << endl;
}

void xorsum_jmp(int *data)
{
    int xorsum = 0;
    timeval start, end;
    gettimeofday(&start, nullptr);
    for (int idx = 0; idx < pagesize; idx++)
    {
        for (int page = 0; page < pagenum; page++)
            xorsum ^= data[page * pagesize + idx];
    }
    gettimeofday(&end, nullptr);
    double usec = (end.tv_sec - start.tv_sec) + (double)(end.tv_usec - start.tv_usec) / 1000000;
    cout << __func__ << " duration: " << usec << ", xorsum: " << xorsum << endl;
}

int main()
{
    int *data = new int[SIZE];
    int xorsum = 0;
    srand(time(nullptr));
    for (int idx = 0; idx < SIZE; idx++)
    {
        data[idx] = rand();
    }
    xorsum_seq(data);
    xorsum_jmp(data);
}