csrc/node-v0.10.24/benchmark/buffers/dataview-set.js

var common = require('../common.js');
var bench = common.createBenchmark(main, {
  type: ['Uint8', 'Uint16LE', 'Uint16BE',
         'Uint32LE', 'Uint32BE',
         'Int8', 'Int16LE', 'Int16BE',
         'Int32LE', 'Int32BE',
         'Float32LE', 'Float32BE',
         'Float64LE', 'Float64BE'],
  millions: [1]
});

const INT8   = 0x7f;
const INT16  = 0x7fff;
const INT32  = 0x7fffffff;
const UINT8  = INT8 * 2;
const UINT16 = INT16 * 2;
const UINT32 = INT32 * 2;

var mod = {
  setInt8: INT8,
  setInt16: INT16,
  setInt32: INT32,
  setUint8: UINT8,
  setUint16: UINT16,
  setUint32: UINT32
};

function main(conf) {
  var len = +conf.millions * 1e6;
  var ab = new ArrayBuffer(8);
  var dv = new DataView(ab, 0, 8);
  var le = /LE$/.test(conf.type);
  var fn = 'set' + conf.type.replace(/[LB]E$/, '');

  if (/int/i.test(fn))
    benchInt(dv, fn, len, le);
  else
    benchFloat(dv, fn, len, le);
}

function benchInt(dv, fn, len, le) {
  var m = mod[fn];
  bench.start();
  for (var i = 0; i < len; i++) {
    dv[fn](0, i % m, le);
  }
  bench.end(len / 1e6);
}

function benchFloat(dv, fn, len, le) {
  bench.start();
  for (var i = 0; i < len; i++) {
    dv[fn](0, i * 0.1, le);
  }
  bench.end(len / 1e6);
}