Why is "or" slower than "and" in Java?

Question

Today I encountered a rather amazing behavior in java, or is slower than and!

I even made a test case that you can see at the below.Now I wonder why this happens? Am I doing something wrong or does it happen just on my computer? I don't see any reason that or should be slower than and specially with this significant difference. I want to test this phenomenon with some other languages, do you have any idea about this in general?

public class TestClass {

    public static void main(String[] args) {

        long[] or = new long[10];
        long[] and = new long[10];
        long lStartTime, lEndTime, difference = 0;
        for (int idx = 0; idx < 10; idx++) {

            lStartTime = System.nanoTime();
            for (int i= 0; i < 1000000000; i++) { 
                int j = i | i+1 ;
            }
            lEndTime = System.nanoTime();
            difference = lEndTime - lStartTime;
            System.out.println("Elapsed milliseconds: " + difference/1000000);
            or[idx] = difference;

            lStartTime = System.nanoTime();
            for (int i= 0; i < 1000000000; i++) {
                int j = i & i+1 ;
            }
            lEndTime = System.nanoTime();
            difference = lEndTime - lStartTime;
            System.out.println("Elapsed milliseconds: " + difference/1000000);  
            and[idx] = difference;
            System.out.println("------------------------------------" );

        }

        long tmp = 0;
        for (long l : or) {
            tmp += l;
        }
        tmp /= 10;
        System.out.println("Elapsed milliseconds for or: " + tmp/1000000);
        tmp = 0;
        for (long l : and) {
            tmp += l;
        }
        tmp /= 10;
        System.out.println("Elapsed milliseconds for and: " + tmp/1000000);
    }
}

results :

Elapsed milliseconds: 1600
Elapsed milliseconds: 1332
------------------------------------
Elapsed milliseconds: 1609
Elapsed milliseconds: 1335
------------------------------------
Elapsed milliseconds: 1609
Elapsed milliseconds: 1335
------------------------------------
Elapsed milliseconds: 1542
Elapsed milliseconds: 1314
------------------------------------
Elapsed milliseconds: 1705
Elapsed milliseconds: 1324
------------------------------------
Elapsed milliseconds: 1559
Elapsed milliseconds: 1315
------------------------------------
Elapsed milliseconds: 1526
Elapsed milliseconds: 1314
------------------------------------
Elapsed milliseconds: 1568
Elapsed milliseconds: 1340
------------------------------------
Elapsed milliseconds: 1551
Elapsed milliseconds: 1318
------------------------------------
Elapsed milliseconds: 1574
Elapsed milliseconds: 1321
------------------------------------
Elapsed milliseconds for or: 1584
Elapsed milliseconds for and: 1325

Answer 1

Bit-Wise OR is not slower than Bit-Wise AND!

Swap between the time-measuring snippets in your code, and you'll get the opposite results:

for (int idx = 0; idx < 10; idx++) {

    lStartTime = System.nanoTime();
    for (int i= 0; i < 1000000000; i++) {
        int j = i & i+1 ;
    }
    lEndTime = System.nanoTime();

    difference = lEndTime - lStartTime;
    System.out.println("Elapsed milliseconds: " + difference/1000000);  
    and[idx] = difference;

    lStartTime = System.nanoTime();
    for (int i= 0; i < 1000000000; i++) { 
        int j = i | i+1 ;
    }
    lEndTime = System.nanoTime();

    difference = lEndTime - lStartTime;
    System.out.println("Elapsed milliseconds: " + difference/1000000);
    or[idx] = difference;

    System.out.println("------------------------------------");
}

I tend to guess that the JVM applies some kind of runtime optimization during the second snippet.