Компиляторы Intel. Возможности автоматической оптимизации

#include "time.h"
#include <iostream>
    #include "stdlib.h"
    #include "conio.h"
    #include "math.h"
    
    using namespace std;
    const int NUM_OF_TESTS = 2000000;
    const int RANGE = 1000;
    bool isComposite(const int y);
    
    int main()
    {
    time_t t1, t2;
    int counter(0);
    t1 = clock();
    for	(int i = 0; i < NUM_OF_TESTS; i++)
    if(isComposite(rand()%RANGE))
    ++counter;
    t2 = clock();
    
    cout << "For " << NUM_OF_TESTS << " pseudo-random values" << endl;
    cout << "within the range 0.." << RANGE << endl;
    cout << ((NUM_OF_TESTS-counter)*100.0)/NUM_OF_TESTS << "% were prime numbers." << endl;
    cout << "\nInitial clock ticks value is " << t1 << endl;
    cout << "Final clock ticks value is " << t2 << endl;
    cout << "Difference in clock ticks is " << difftime(t2,t1) << endl;
    cout << "Clock ticks per second value is " << CLOCKS_PER_SEC << endl;
    cout << "\nActual time of calculations is " << ((t2-t1)/CLOCKS_PER_SEC) << " sec" << endl;
    return 0;
    }
    
    bool isComposite(const int y)
    {
    bool result = false;
    
    for (int i = 2; i <= ceil(y/2.0); i++)
        {	
        if (y%i == 0) result = true;
        }
        return result;
        }
        
        

#include "time.h"
#include <iostream>
    #include "stdlib.h"
    #include "conio.h"
    #include "math.h"
    using namespace std;
    const int RANGE = 2000;
    long sumOfCubes(const int x, const int y);
    int main()
    {
    time_t t1, t2;
    bool isDisproven = false;
    cout << "Checking for mispredictions of Fermat's Great Theorem" << endl;
    cout << "for cubes in range 3.." << RANGE << endl;
    t1 = clock();
    for (int i = 3; i < RANGE; i++)
    {
    for(int k = 1; k < i; k++)
    {
    for(int j = 1; j < i; j++)
    {
    if (long(i*i*i) == sumOfCubes(k,j)) 
    {
    cout << k << " " << j << " " << i << endl;
    isDisproven = true;
    }
    }
    }
    }
    t2 = clock();
    cout << "\nAre theorem's predictions correct? +" << !(isDisproven) << endl;
    cout << "\nInitial clock ticks value is " << t1 << endl;
    cout << "Final clock ticks value is " << t2 << endl;
    cout << "Difference in clock ticks is " << difftime(t2,t1) << endl;
    cout << "Clock ticks per second value is " << CLOCKS_PER_SEC << endl;
    cout << "\nActual time of calculations is " << ((t2-t1)/CLOCKS_PER_SEC) << " sec" << endl;
    return 0;
    }
    long sumOfCubes(const int x, const int y)
    {
    return (x*x*x + y*y*y);
    }    
        

#include "time.h"
#include <iostream>
    #include "stdlib.h"
    #include "conio.h"
    #include "math.h"
    using namespace std;
    bool slow_func(void);
    bool quick_func(void);
    
    int main()
    {
    time_t t1, t2;
    t1 = clock();
    if(slow_func() && quick_func()) cout << "You can't see this...";
    t2 = clock();
    cout << "\nInitial clock ticks value is " << t1 << endl;
    cout << "Final clock ticks value is " << t2 << endl;
    cout << "Difference in clock ticks is " << difftime(t2,t1) << endl;
    cout << "Clock ticks per second value is " << CLOCKS_PER_SEC << endl;
    cout << "\nActual time of calculations is " << ((t2-t1)/CLOCKS_PER_SEC) << " sec" << endl;
    return 0;
    }
    
    bool slow_func(void)
    {	
    double a(0);
    for(int i = 0; i < 50000000; i++) 
    a = pow((sin(a/2.0)+cos(a/2.0))*(sin(i/2.0)+cos(i/2.0)), 2);
    for(int i = 0; i < 100; i++)
    a += i;
    return !a;
    }
    
    bool quick_func(void)
    {	
    return false;
    }