Fastest array loops in Javascript (v343)

Revision 343 of this benchmark created by Rulin on

Preparation HTML

<script>
    // Populate the base array
    var arr = [];
    for (var i = 0; i < 1000; i++) {
        arr[i] = i;
    }
    function someFn(ix) {
        return ix * 5 + 1 / 3 * 8;
    }
</script>

Test runner

Ready to run.

Testing in
TestOps/sec
for loop - basic
for (var i = 0; i < arr.length; i++) {
    someFn(arr[i]);
}
ready
for loop - cache length in for loop
for (var i = 0, len = arr.length; i < len; i++) {
    someFn(arr[i]);
}
ready
for loop - cache length outside
var len = arr.length;
for (var i = 0; i < len; i++) {
    someFn(arr[i]);
}
ready
for loop - reverse - basic
for (var i = arr.length; i;) {
    i--;
    someFn(arr[i]);
}
ready
for loop - reverse - cache length outside
var len = arr.length;
for (var i = len; i;) {
    i--;
    someFn(arr[i]);
}
ready

Revisions

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