Run results for: for loop vs for-of with index variable2

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:81.0) Gecko/20100101 Firefox/81.0

Browser: Firefox 81

Operating system: Mac OS X 10.14

Device Platform: Desktop

Date tested: 3 years ago

Test name	Executions per second
for	4821.0 Ops/sec
for of with index	4123.5 Ops/sec

Script Preparation code:

   var arr1 = [];
   var arr2 = [];
   for (var i = 0; i < 10000; i++) {
       arr1[i] = i;
       arr2[i] = i;
   }

Tests:

for
var arr = []; for (var i = 0; i < arr2.length; i++) { arr.push({ a: arr1[i], b: arr2[i] }); }
for of with index
var arr = []; var index = 0; for (var val of arr2) { arr.push({ a: arr1[index++], b: arr2 }); }