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Unrolled loops (v6)

Revision 6 of this benchmark created by Ryan Tenney on August 16, 2010

Description

It seems the latest and greatest JavaScript engines have caught up and loop unrolling is not the great optimization it once was. Still, both unrolled loop variants are 10% to 25% faster than the for loop on both Safari 5 and Chrome 5.

Preparation HTML

<script>
  var a = 0;
</script>

Test runner

Ready to run.

Test Ops/sec

For loop

Testing in
Test	Ops/sec
For loop	`for (var i = 0; i < 100; i++) a++;`	ready
Unrolled loop	`a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++; a++;`	ready
Unrolled loop (1 statement)	`a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++;`	ready

for (var i = 0; i < 100; i++) a++;

ready

Unrolled loop

a++;
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ready

Unrolled loop (1 statement)

a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++, a++;

ready

Revisions

You can edit these tests or add more tests to this page by appending /edit to the URL.

Revision 1: published by Thomas Fuchs on August 16, 2010
Revision 2: published by elliottcable on August 16, 2010
Revision 3: published by Kristof Neirynck on August 16, 2010
Revision 4: published by Micheil Smith on August 16, 2010
Revision 6: published by Ryan Tenney on August 16, 2010
Revision 7: published by gonchuki on August 16, 2010
Revision 8: published by TW on August 16, 2010
Revision 11: published on August 18, 2010
Revision 16: published on February 23, 2015