Run results for: log 2 for integers less than 1^^31

Run details:

User agent: Mozilla/5.0 (X11; Ubuntu; Linux i686; rv:61.0) Gecko/20100101 Firefox/61.0

Browser: Firefox 61

Operating system: Ubuntu

Device Platform: Desktop

Date tested: 6 years ago

Test name	Executions per second
standard lib	1648162.0 Ops/sec
dicho integer oriented	1271091.0 Ops/sec
dicho integer oriented 2	1039823.0 Ops/sec
dicho integer oriented 3	1088036.0 Ops/sec

Script Preparation code:

function ll(x){
  let b=0, l=16, tmp;
  while (l){
    tmp = b+l;
    if (x & ((-1)<<tmp)) {
      b = tmp;
    }
    l = l>>>1;
  }
  return b;
}
function ll2(x){
  let b=0, l=16, tmp;
  while (l){
    tmp = b+l;
    if (x>>>tmp) {
      b = tmp;
    }
    l = l>>>1;
  }
  return b;
}
function ll3(x){
  let b=0, l=16;
  while (l){
    if (x>>>(b+l)) {
      b += l;
    }
    l = l>>>1;
  }
  return b;
}

var test = [...Array(50)].map(()=>(((-1)>>>1)*Math.random())>>0)

Tests:

standard lib
for (var i=0; i<test.length; i++) Math.log2(test[i])>>0;
dicho integer oriented
for (var i=0; i<test.length; i++) ll(test[i]);
dicho integer oriented 2
for (var i=0; i<test.length; i++) ll2(test[i]);
dicho integer oriented 3
for (var i=0; i<test.length; i++) ll3(test[i]);

Run results for: log 2 for integers less than 1^^31

standard lib

dicho integer oriented

dicho integer oriented 2

dicho integer oriented 3