Prefix or Postfix increment?

JavaScript performance comparison

Revision 9 of this test case created on 6th September 2012

So with recent JS runtimes, does using the prefix increment/decrement operators squeeze the usual performance droplet from loop index maintenance?

<script>
  var data = new Array(500 * 1000);
  var index = data.length - 1;
  while (index--) data[index] = index;
</script>

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Java applet disabled.

Test Ops/sec

Testing in unknown unknown
Test	Ops/sec
Prefix	`for (var index = 0, len = data.length; index < len; ++index) { data[index] = data[index] * 2; }`	pending…
Suffix	`for (var index = 0, len = data.length; index < len; index++) { data[index] = data[index] * 2; }`	pending…
Crockford	`for (var index = 0, len = data.length; index < len; index += 1) { data[index] = data[index] * 2; }`	pending…

Prefix

for (var index = 0, len = data.length; index < len; ++index) {
  data[index] = data[index] * 2;
}

pending…

Suffix

for (var index = 0, len = data.length; index < len; index++) {
  data[index] = data[index] * 2;
}

pending…

Crockford

for (var index = 0, len = data.length; index < len; index += 1) {
  data[index] = data[index] * 2;
}

pending…

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