Important Note

It’s very important to say that the following results are dependant from the machine and the environment!

Source Code

Here’s the PHP source code.

function divide($n = 1) 
{
	$a = microtime(true);
	for ($i = 0; $i < $n; $i++) {
		300/2;
	}
	echo microtime(true) - $a;
}

divide(100);
//divide(1000);
//divide(10000);
//divide(100000);
//divide(1000000);
//divide(10000000);

and bitwise ...

function bitwise($n = 1)
{
	$a = microtime(true);
	for ($i = 0; $i < $n; $i++) {
		300 >> 1;
	}
	echo microtime(true) - $a;
}

bitwise(100);
//bitwise(1000);
//bitwise(10000);
//bitwise(100000);
//bitwise(1000000);
//bitwise(10000000);

Note that each method was called 6 times with the same parameter. This means that divide(100) was called 6 times and then I used the average value of these six times.

Results

I said back then in my binary search post, that in PHP the bitwise operator ">> 1" is not faster than the typical division with the "/" operator. However the results tells us that using bitwise division is slightly faster, as you can see at the diagram bellow.

n		">>"			"/"
100		0.0002334912618		0.000311803817749
1000		0.001911004384359	0.007335503896078
10000		0.013423800468445	0.039460102717081
100000		0.14417803287506	0.21413381894429
1000000		1.15839115778605	1.17152162392935
10000000	10.556711634		11.0911625623705

Conclusion

Although bitwise division is a bit faster the difference is so small that you should work with very large data in order to gain some performance.