Benchmark: log 2 for integers less than 1^^31

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]);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
standard lib
dicho integer oriented
dicho integer oriented 2
dicho integer oriented 3

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: 6 years ago)

User agent: Mozilla/5.0 (X11; Linux i686) AppleWebKit/537.36 (KHTML, like Gecko) Ubuntu Chromium/67.0.3396.99 Chrome/67.0.3396.99 Safari/537.36

Browser/OS: Chromium 67 on Ubuntu

View result in a separate tab

Test name	Executions per second
standard lib	45977.2 Ops/sec
dicho integer oriented	59989.2 Ops/sec
dicho integer oriented 2	60515.2 Ops/sec
dicho integer oriented 3	60840.7 Ops/sec

log 2 for integers less than 1^^31 (version: 4)

Comparing performance of: standard lib vs dicho integer oriented vs dicho integer oriented 2 vs dicho integer oriented 3

Created: 6 years ago by: Registered User

Jump to the latest result

standard lib

dicho integer oriented

dicho integer oriented 2

dicho integer oriented 3

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A