#include <iostream>
#include <random>
#include <cstdint>
#include <Windows.h>
#include <vector>

//======================================================
//Дабы избежать оптимизаций компилятора

uint64_t gGlobalVar = 0;

DECLSPEC_NOINLINE void Inc5()
{
    gGlobalVar += 5;
}

DECLSPEC_NOINLINE void Inc7()
{
    gGlobalVar += 7;
}

//======================================================

std::vector<uint8_t> GenRandomVec(size_t size)
{
    std::random_device rd;
    std::mt19937_64 mt(rd());

    std::vector<uint8_t> constVec(size);
    std::uniform_int_distribution<int> distrib;
    for (uint64_t i = 0; i < constVec.size(); i++)
    {
        constVec[i] = distrib(mt) & 0xff;
    }

    return std::move(constVec);
}

//======================================================

double BranchedTime(int64_t timeFreq, uint8_t threshold, const std::vector<uint8_t>& randomConditions)
{
    int64_t start, end;

    QueryPerformanceCounter((LARGE_INTEGER*)(&start));
    for (uint64_t i = 0; i < randomConditions.size(); i++)
    {
        if (randomConditions[i] > threshold)
        {
            Inc5();
        }
        else
        {
            Inc7();
        }
    }
    QueryPerformanceCounter((LARGE_INTEGER*)(&end));

    return (double)(end - start) / timeFreq;
}

double UnbranchedTime(int64_t timeFreq, uint8_t threshold, const std::vector<uint8_t>& randomConditions)
{
    int64_t start, end;

    void(*Incs[2])() = { Inc7, Inc5 };

    QueryPerformanceCounter((LARGE_INTEGER*)(&start));
    for (uint64_t i = 0; i < randomConditions.size(); i++)
    {
        Incs[randomConditions[i] > threshold]();
    }
    QueryPerformanceCounter((LARGE_INTEGER*)(&end));

    return (double)(end - start) / timeFreq;
}

//======================================================

int main()
{
    uint8_t threshold = 127;
    std::vector<uint8_t> cVec = std::move(GenRandomVec(1000000000)); //1 billion

    int64_t freq;
    QueryPerformanceFrequency((LARGE_INTEGER*)(&freq));

    double bTime = BranchedTime(freq, threshold, cVec);
    double uTime = UnbranchedTime(freq, threshold, cVec);

    std::cout << "Branched   time = " << bTime << std::endl
              << "Unbranched time = " << uTime << std::endl;

    std::cin.get();
    return 0;
}