benchmarks: add microbenchmarks for new ES6 features

Adds new microbenchmarks for destructuring, rest params and
default params.

PR-URL: https://github.com/nodejs/node/pull/6222
Reviewed-By: Brian White <mscdex@mscdex.net>

1 files changed, 58 insertions, 0 deletions

diff --git a/benchmark/es/defaultparams-bench.js b/benchmark/es/defaultparams-bench.js
new file mode 100644
index 0000000000..1b962cfb39
--- /dev/null
+++ b/benchmark/es/defaultparams-bench.js
@@ -0,0 +1,58 @@
+'use strict';
+
+const common = require('../common.js');
+const assert = require('assert');
+
+const bench = common.createBenchmark(main, {
+  method: ['withoutdefaults', 'withdefaults'],
+  millions: [100]
+});
+
+function oldStyleDefaults(x, y) {
+  x = x || 1;
+  y = y || 2;
+  assert.strictEqual(x, 1);
+  assert.strictEqual(y, 2);
+}
+
+function defaultParams(x = 1, y = 2) {
+  assert.strictEqual(x, 1);
+  assert.strictEqual(y, 2);
+}
+
+function runOldStyleDefaults(n) {
+
+  common.v8ForceOptimization(oldStyleDefaults);
+
+  var i = 0;
+  bench.start();
+  for (; i < n; i++)
+    oldStyleDefaults();
+  bench.end(n / 1e6);
+}
+
+function runDefaultParams(n) {
+
+  common.v8ForceOptimization(defaultParams);
+
+  var i = 0;
+  bench.start();
+  for (; i < n; i++)
+    defaultParams();
+  bench.end(n / 1e6);
+}
+
+function main(conf) {
+  const n = +conf.millions * 1e6;
+
+  switch (conf.method) {
+    case 'withoutdefaults':
+      runOldStyleDefaults(n);
+      break;
+    case 'withdefaults':
+      runDefaultParams(n);
+      break;
+    default:
+      throw new Error('Unexpected method');
+  }
+}