undefined vs local undefined var

JavaScript performance comparison

Revision 2 of this test case created by @blixt

Preparation code

 
<script>
Benchmark.prototype.setup = function() {
    function test1(stuff) {
      if (stuff === undefined) {
        stuff += stuff; // never reached
      }
    }
   
    function test2(stuff, u) {
      if (stuff === u) {
        stuff += stuff; // never reached
      }
    }
};
</script>

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Testing in unknown unknown
Test Ops/sec
global undefined
test1(1);
pending…
local undefined var
test2(1);
pending…

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