gistfile1.js

var start = Date.now(),
    i = 1e5,
    a = [0,1,2,3,4,5,6,7,8,9],
    total, l, j;

while(i--){
total = 0;
// uncomment the line you want to test
l = a.length; while(l--){ total = total + a[l]; }
//for(j = 0, l=a.length; j < l; j++){ total = total + a[j]; }
//dojo.forEach(a, function(i){ total = total + i; });
//a.forEach(function(i){total = total + i});
}
console.log(Date.now() - start);