Strange performance affects from wrapping try/catch into a function

y0.js

// ../jsshell-35.0/js y0.js
// TryCatch x 2,139,927 ops/sec ±0.96% (65 runs sampled)
// FastTry x 2,079,778 ops/sec ±1.07% (63 runs sampled)
// Fastest is TryCatch


load("lodash.js");
load("benchmark.js");

function fastTry (fn) {
  try {
    return fn();
  }
  catch (e) {
    if (!(e instanceof Error)) {
      return new Error(e);
    }
    else {
      return e;
    }
  }
}

function factorial(op) {
  // Lanczos Approximation of the Gamma Function
  // As described in Numerical Recipes in C (2nd ed. Cambridge University Press, 1992)
  var z = op + 1;
  var p = [1.000000000190015, 76.18009172947146, -86.50532032941677, 24.01409824083091, -1.231739572450155, 1.208650973866179E-3, -5.395239384953E-6];

  var d1 = Math.sqrt(2 * Math.PI) / z;
  var d2 = p[0];

  for (var i = 1; i <= 6; ++i) {
    d2 += p[i] / (z + i);
  }

  var d3 = Math.pow((z + 5.5), (z + 0.5));
  var d4 = Math.exp(-(z + 5.5));

  d = d1 * d2 * d3 * d4;

  return d;
}

var suite = new Benchmark.Suite();
suite
  .add('TryCatch', function () {
    try {
      var d = 0;
      d += factorial(10 * Math.random());
      d += factorial(2 * Math.random());
      return d;
    }
    catch (e) {
      return e;
    }
  })
  .add('FastTry', function () {
    return fastTry(function () {
      var d = 0;
      d += factorial(10 * Math.random());
      d += factorial(2 * Math.random());
      return d;
    });
  })
  .on('cycle', function(event) {
    print(String(event.target));
  })
  .on('complete', function() {
    print('Fastest is ' + this.filter('fastest').pluck('name'));
  })
  .run({'async': false});

y1.js

// ../jsshell-35.0/js y1.js
// TryCatch x 55,174 ops/sec ±3.26% (57 runs sampled)
// FastTry x 42,571 ops/sec ±4.10% (57 runs sampled)
// Fastest is TryCatch

load("lodash.js");
load("benchmark.js");

function fastTry (fn) {
  try {
    return fn();
  }
  catch (e) {
    if (!(e instanceof Error)) {
      return new Error(e);
    }
    else {
      return e;
    }
  }
}

(function () {



function factorial(op) {
  // Lanczos Approximation of the Gamma Function
  // As described in Numerical Recipes in C (2nd ed. Cambridge University Press, 1992)
  var z = op + 1;
  var p = [1.000000000190015, 76.18009172947146, -86.50532032941677, 24.01409824083091, -1.231739572450155, 1.208650973866179E-3, -5.395239384953E-6];

  var d1 = Math.sqrt(2 * Math.PI) / z;
  var d2 = p[0];

  for (var i = 1; i <= 6; ++i) {
    d2 += p[i] / (z + i);
  }

  var d3 = Math.pow((z + 5.5), (z + 0.5));
  var d4 = Math.exp(-(z + 5.5));

  d = d1 * d2 * d3 * d4;

  return d;
}

var suite = new Benchmark.Suite();
suite
  .add('TryCatch', function () {
    try {
      var d = 0;
      d += factorial(10 * Math.random());
      d += factorial(2 * Math.random());
      return d;
    }
    catch (e) {
      return e;
    }
  })
  .add('FastTry', function () {
    return fastTry(function () {
      var d = 0;
      d += factorial(10 * Math.random());
      d += factorial(2 * Math.random());
      return d;
    });
  })
  .on('cycle', function(event) {
    print(String(event.target));
  })
  .on('complete', function() {
    print('Fastest is ' + this.filter('fastest').pluck('name'));
  })
  .run({'async': false});

})();

y2.js

// ../jsshell-35.0/js y2.js
// TryCatch x 54,241 ops/sec ±3.49% (58 runs sampled)
// FastTry x 2,092,810 ops/sec ±1.27% (62 runs sampled)
// Fastest is FastTry

load("lodash.js");
load("benchmark.js");

(function () {

function fastTry (fn) {
  try {
    return fn();
  }
  catch (e) {
    if (!(e instanceof Error)) {
      return new Error(e);
    }
    else {
      return e;
    }
  }
}

function factorial(op) {
  // Lanczos Approximation of the Gamma Function
  // As described in Numerical Recipes in C (2nd ed. Cambridge University Press, 1992)
  var z = op + 1;
  var p = [1.000000000190015, 76.18009172947146, -86.50532032941677, 24.01409824083091, -1.231739572450155, 1.208650973866179E-3, -5.395239384953E-6];

  var d1 = Math.sqrt(2 * Math.PI) / z;
  var d2 = p[0];

  for (var i = 1; i <= 6; ++i) {
    d2 += p[i] / (z + i);
  }

  var d3 = Math.pow((z + 5.5), (z + 0.5));
  var d4 = Math.exp(-(z + 5.5));

  d = d1 * d2 * d3 * d4;

  return d;
}

var suite = new Benchmark.Suite();
suite
  .add('TryCatch', function () {
    try {
      var d = 0;
      d += factorial(10 * Math.random());
      d += factorial(2 * Math.random());
      return d;
    }
    catch (e) {
      return e;
    }
  })
  .add('FastTry', function () {
    return fastTry(function () {
      var d = 0;
      d += factorial(10 * Math.random());
      d += factorial(2 * Math.random());
      return d;
    });
  })
  .on('cycle', function(event) {
    print(String(event.target));
  })
  .on('complete', function() {
    print('Fastest is ' + this.filter('fastest').pluck('name'));
  })
  .run({'async': false});

})();