Debunk method calls in loop conditions

JavaScript performance comparison

Revision 11 of this test case created

Preparation code

 
<script>
Benchmark.prototype.setup = function() {
    var my_array = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];
   
    function myMethod() {
      return my_array.length;
    };
    var dummy;
};
</script>

Test runner

Warning! For accurate results, please disable Firebug before running the tests. (Why?)

Java applet disabled.

Testing in unknown unknown
Test Ops/sec
slow.length
dummy = 0;
for (var i = 0; i < my_array.length; i++) {
  dummy += i;
}
pending…
fast.length
dummy = 0;
var length = my_array.length;
for (var i = 0; i < length; i++) {
  dummy += i;
}
pending…
test
dummy = 0;
for (var i = 0, e;
  (e = my_array[i]) != null; i++) {
  dummy += i;
}
pending…
slow.call
dummy = 0;
for (var i = 0; i < myMethod(); i++) {
  dummy += i;
}
pending…
fast.call
dummy = 0;
var length = myMethod();
for (var i = 0; i < length; i++) {
  dummy += i;
}
pending…

Compare results of other browsers

Revisions

You can edit these tests or add even more tests to this page by appending /edit to the URL. Here’s a list of current revisions for this page:

0 comments

Add a comment