benchmark: remove querystring forced optimization

This removes all instances of %OptimizeFunctionOnNextCall from
querystring benchmarks

PR-URL: https://github.com/nodejs/node/pull/9615
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>

benchmark/querystring/querystring-parse.js

@@ -1,7 +1,6 @@
 'use strict';
 var common = require('../common.js');
 var querystring = require('querystring');
-var v8 = require('v8');
 var inputs = require('../fixtures/url-inputs.js').searchParams;
 
 var bench = common.createBenchmark(main, {
@@ -9,23 +8,13 @@ var bench = common.createBenchmark(main, {
   n: [1e6],
 });
 
-// A deopt followed by a reopt of main() can happen right when the timed loop
-// starts, which seems to have a noticeable effect on the benchmark results.
-// So we explicitly disable optimization of main() to avoid this potential
-// issue.
-v8.setFlagsFromString('--allow_natives_syntax');
-eval('%NeverOptimizeFunction(main)');
-
 function main(conf) {
   var type = conf.type;
   var n = conf.n | 0;
   var input = inputs[type];
   var i;
-
-  // Note: we do *not* use OptimizeFunctionOnNextCall() here because currently
-  // it causes a deopt followed by a reopt, which could make its way into the
-  // timed loop. Instead, just execute the function a "sufficient" number of
-  // times before the timed loop to ensure the function is optimized just once.
+  // Execute the function a "sufficient" number of times before the timed
+  // loop to ensure the function is optimized just once.
   if (type === 'multicharsep') {
     for (i = 0; i < n; i += 1)
       querystring.parse(input, '&&&&&&&&&&');

benchmark/querystring/querystring-stringify.js

@@ -1,7 +1,6 @@
 'use strict';
 var common = require('../common.js');
 var querystring = require('querystring');
-var v8 = require('v8');
 
 var bench = common.createBenchmark(main, {
   type: ['noencode', 'encodemany', 'encodelast'],
@@ -36,10 +35,6 @@ function main(conf) {
   for (var name in inputs)
     querystring.stringify(inputs[name]);
 
-  v8.setFlagsFromString('--allow_natives_syntax');
-  eval('%OptimizeFunctionOnNextCall(querystring.stringify)');
-  querystring.stringify(input);
-
   bench.start();
   for (var i = 0; i < n; i += 1)
     querystring.stringify(input);