[test] Add JSTest benchmark for object literal spread

Bug: v8:7611
Change-Id: Ia5467fd4da3b385568bcc3f3fdc1a8c56bd6340e
Reviewed-on: https://chromium-review.googlesource.com/987321Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52313}

test/js-perf-test/JSTests.json

@@ -351,6 +351,21 @@
         {"name": "ValuesMegamorphic"}
       ]
     },
+    {
+      "name": "ObjectLiteralSpread",
+      "path": ["ObjectLiteralSpread"],
+      "main": "run.js",
+      "resources": [],
+      "results_regexp": "^%s\\-ObjectLiteralSpread\\(Score\\): (.+)$",
+      "tests": [
+        {"name": "Babel"},
+        {"name": "BabelAndOverwrite"},
+        {"name": "ObjectAssign"},
+        {"name": "ObjectAssignAndOverwrite"},
+        {"name": "ObjectSpread"},
+        {"name": "ObjectSpreadAndOverwrite"}
+      ]
+    },
     {
       "name": "Scope",
       "path": ["Scope"],

test/js-perf-test/ObjectLiteralSpread/run.js

+// Copyright 2018 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.
+
+const input = {
+  a: 1,
+  b: 2,
+  c: 3,
+  ['d']: 4,
+  1: 5
+};
+
+
+// ----------------------------------------------------------------------------
+// Benchmark: Babel
+// ----------------------------------------------------------------------------
+
+function _extends(target) {
+  for (var i = 1; i < arguments.length; i++) {
+    var source = arguments[i];
+    for (var key in source) {
+      if (Object.prototype.hasOwnProperty.call(source, key)) {
+        target[key] = source[key];
+      }
+    }
+  }
+  return target;
+};
+
+function Babel() {
+  const result = _extends({}, input);
+  if (Object.keys(result).length != 5) throw 666;
+}
+
+function BabelAndOverwrite() {
+  const result = _extends({}, input, {a: 6});
+  if (Object.keys(result).length != 5) throw 666;
+}
+
+// ----------------------------------------------------------------------------
+// Benchmark: Object.assign
+// ----------------------------------------------------------------------------
+
+
+function ObjectAssign() {
+  const result = Object.assign({}, input);
+  if (Object.keys(result).length != 5) throw 666;
+}
+
+function ObjectAssignAndOverwrite() {
+  const result = Object.assign({}, input, {a : 6});
+  if (Object.keys(result).length != 5) throw 666;
+}
+
+
+// ----------------------------------------------------------------------------
+// Benchmark: Object.assign
+// ----------------------------------------------------------------------------
+
+
+function ObjectSpread() {
+  const result = { ...input };
+  if (Object.keys(result).length != 5) throw 666;
+}
+
+function ObjectSpreadAndOverwrite() {
+  const result = { ...input, a: 6 };
+  if (Object.keys(result).length != 5) throw 666;
+}
+
+// ----------------------------------------------------------------------------
+// Setup and Run
+// ----------------------------------------------------------------------------
+
+load('../base.js');
+
+var success = true;
+
+function PrintResult(name, result) {
+  print(name + '-ObjectLiteralSpread(Score): ' + result);
+}
+
+function PrintError(name, error) {
+  PrintResult(name, error);
+  success = false;
+}
+
+function CreateBenchmark(name, f) {
+  new BenchmarkSuite(name, [100], [ new Benchmark(name, false, false, 0, f) ]);
+}
+
+CreateBenchmark('Babel', Babel);
+CreateBenchmark('BabelAndOverwrite', BabelAndOverwrite);
+CreateBenchmark('ObjectAssign', ObjectAssign);
+CreateBenchmark('ObjectAssignAndOverwrite', ObjectAssignAndOverwrite);
+CreateBenchmark('ObjectSpread', ObjectSpread);
+CreateBenchmark('ObjectSpreadLiteral', ObjectSpreadLiteral);
+
+BenchmarkSuite.config.doWarmup = undefined;
+BenchmarkSuite.config.doDeterministic = undefined;
+BenchmarkSuite.RunSuites({NotifyResult: PrintResult, NotifyError: PrintError});