Run results for: Loop Optimization

Run details:

User agent: Mozilla/5.0 (Linux; Android 6.0.1; SAMSUNG SM-T805 Build/MMB29K) AppleWebKit/537.36 (KHTML, like Gecko) SamsungBrowser/6.4 Chrome/56.0.2924.87 Safari/537.36

Browser: Chrome 56

Operating system: Android 6.0.1

Device Platform: Samsung SM-T805

Date tested: 6 years ago

Test name	Executions per second
For loop, basic	34.3 Ops/sec
While loop, basic	33.9 Ops/sec
For loop, cached (inside for statement)	45.5 Ops/sec
For loop, cached (outside for statement)	45.6 Ops/sec
For loop, i-- (caching inside for loop)	43.8 Ops/sec
For loop, i-- (caching outside for loop)	39.0 Ops/sec
While loop, cached	44.1 Ops/sec
While loop, i--	46.4 Ops/sec
forEach	51.7 Ops/sec

Script Preparation code:

  var arr = [];
  for (var i = 0; i < 10000; i++) {
    arr.push(i);
  }

var sum = 0;

Tests:

For loop, basic
for (var i = 0; i < arr.length; i++) { sum += arr[i]; }
While loop, basic
var i = 0; while (i < arr.length) { sum += arr[i]; i++; }
For loop, cached (inside for statement)
for (var i = 0, len = arr.length; i < len; i++) { sum += arr[i]; }
For loop, cached (outside for statement)
var len = arr.length; for (var i = 0; i < len; i++) { sum += arr[i]; }
For loop, i-- (caching inside for loop)
for (var i = arr.length; i > 0; i--) { sum += arr[i]; }
For loop, i-- (caching outside for loop)
var i = arr.length; for (; i--;) { sum += arr[i]; }
While loop, cached
var len = arr.length; var i = 0; while(i < len){ sum += arr[i]; i++; }
While loop, i--
var i = arr.length; while(i--){ sum += arr[i]; }
forEach
arr.forEach(function(val){ sum += val; });

Run results for: Loop Optimization

Checking differences between various for/while loops.

For loop, basic

While loop, basic

For loop, cached (inside for statement)

For loop, cached (outside for statement)

For loop, i-- (caching inside for loop)

For loop, i-- (caching outside for loop)

While loop, cached

While loop, i--

forEach