JavaScript bitwise NOT vs Math.floor()

JavaScript performance comparison

Revision 2 of this test case created

Info

Simple test to check the difference in performance of JavaScript Math.floor() vs double bitwise NOT operator: ~~.

More info here: http://rocha.la/JavaScript-bitwise-operators-in-practice

Edit: Added >>0 and |0 as well.

Preparation code

 
<script>
Benchmark.prototype.setup = function() {
    var numbers = [];
   
    //generate amount random numbers
    for (var i = 0; i < 100000; i++) {
      numbers[numbers.length] = Math.random() * 100000;
    }
};
</script>

Test runner

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Testing in unknown unknown
Test Ops/sec
Math.floor()
var test;
for (var i = 0; i < 100000; i++) {
  test = Math.floor(numbers[i]);
}
pending…
bitwise NOT
var test;
for (var i = 0; i < 100000; i++) {
  test = ~~ (numbers[i]);
}
pending…
Bitwise OR
var test;
for (var i = 0; i < 100000; i++) {
  test = (numbers[i]) | 0;
}
pending…
Bitwise SHIFT
var test;
for (var i = 0; i < 100000; i++) {
  test = (numbers[i]) >> 0;
}
pending…

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Revisions

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