JavaScript bitwise NOT vs Math.floor()

JavaScript performance comparison

Revision 13 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>

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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…
parseInt
var test;
for (var i = 0; i < 100000; i++) {
  test = parseInt(numbers[i]);
}
pending…

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Revisions

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