[test] Add micro benchmark for Object.create

test/js-perf-test/Object/create.js

+// Copyright 2016 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// ----------------------------------------------------------------------------
+
+function shallowClone(object) {
+  return Object.create(object.__proto__,
+      Object.getOwnPropertyDescriptors(object));
+}
+
+function makeSlowCopy(object) {
+  object = shallowClone(object);
+  object.__foo__ = 1;
+  delete object.__foo__;
+  return object;
+}
+
+function convertToPropertyDescriptors(dict) {
+  for (var key in dict) {
+    var propertiesObject = dict[key];
+    dict[key] = Object.getOwnPropertyDescriptors(propertiesObject);
+  }
+  return dict;
+}
+
+var properties_5 = { a:1, b:2, c:3, d:4, e:5 };
+var TEST_PROPERTIES = convertToPropertyDescriptors({
+  empty: {},
+  array_5: [1, 2, 3, 4, 5],
+  properties_5: properties_5,
+  properties_10: { a:1, b:2, c:3, d:4, e:5, f:6, g:7, h:8, i:9, j:10 },
+  properties_dict: makeSlowCopy(properties_5)
+});
+
+var TEST_PROTOTYPES = {
+  null: null,
+  empty: {},
+  'Object.prototype': Object.prototype,
+  'Array.prototype': Array.prototype
+};
+
+// ----------------------------------------------------------------------------
+
+var testFunction = () => {
+  return Object.create(prototype, properties);
+}
+
+function createTestFunction(prototype, properties) {
+  // Force a new function for each test-object to avoid side-effects due to ICs.
+  var random_comment = "\n// random comment" + Math.random() + "\n";
+  return eval(random_comment + testFunction.toString());
+}
+
+// ----------------------------------------------------------------------------
+
+var benchmarks = []
+
+for (var proto_name in TEST_PROTOTYPES) {
+  var prototype = TEST_PROTOTYPES[proto_name];
+  for (var prop_name in TEST_PROPERTIES) {
+    var properties = TEST_PROPERTIES[prop_name];
+    var name = 'Create proto:' + proto_name + " properties:" + prop_name;
+    benchmarks.push(
+        new Benchmark(name, false, false, 0,
+          createTestFunction(prototype, properties)));
+  }
+}
+
+new BenchmarkSuite('Create', [1000], benchmarks);