String.prototype.{match,search} should do only one RegExp brand check

src/js/string.js

 // Copyright 2012 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(global, utils) {
 
 %CheckIsBootstrapping();
 
 // -------------------------------------------------------------------
 // Imports
 
 var ArrayIndexOf;
 var ArrayJoin;
 var GlobalRegExp = global.RegExp;
 var GlobalString = global.String;
 var InternalArray = utils.InternalArray;
 var InternalPackedArray = utils.InternalPackedArray;
 var IsRegExp;
 var MakeRangeError;
 var MakeTypeError;
 var MaxSimple;
 var MinSimple;
+var RegExpInitialize;
 var matchSymbol = utils.ImportNow("match_symbol");
 var replaceSymbol = utils.ImportNow("replace_symbol");
 var searchSymbol = utils.ImportNow("search_symbol");
 var splitSymbol = utils.ImportNow("split_symbol");
 
 utils.Import(function(from) {
   ArrayIndexOf = from.ArrayIndexOf;
   ArrayJoin = from.ArrayJoin;
   IsRegExp = from.IsRegExp;
   MakeRangeError = from.MakeRangeError;
   MakeTypeError = from.MakeTypeError;
   MaxSimple = from.MaxSimple;
   MinSimple = from.MinSimple;
+  RegExpInitialize = from.RegExpInitialize;
 });
 
 //-------------------------------------------------------------------
 
 // ECMA-262 section 15.5.4.2
 function StringToString() {
   if (!IS_STRING(this) && !IS_STRING_WRAPPER(this)) {
     throw MakeTypeError(kNotGeneric, 'String.prototype.toString');
   }
   return %_ValueOf(this);
@@ skipping 106 matching lines @@
 
   if (!IS_NULL_OR_UNDEFINED(pattern)) {
     var matcher = pattern[matchSymbol];
     if (!IS_UNDEFINED(matcher)) {
       return %_Call(matcher, pattern, this);
     }
   }
 
   var subject = TO_STRING(this);
 
-  // Non-regexp argument.
-  var regexp = new GlobalRegExp(pattern);
+  // Equivalent to RegExpCreate (ES#sec-regexpcreate)
+  var regexp = %NewObject(GlobalRegExp, GlobalRegExp);
+  RegExpInitialize(regexp, pattern);
   return regexp[matchSymbol](subject);
 }
 
 
 // ECMA-262 v6, section 21.1.3.12
 //
 // For now we do nothing, as proper normalization requires big tables.
 // If Intl is enabled, then i18n.js will override it and provide the the
 // proper functionality.
 function StringNormalize(formArg) {  // length == 0
@@ skipping 174 matching lines @@
   CHECK_OBJECT_COERCIBLE(this, "String.prototype.search");
 
   if (!IS_NULL_OR_UNDEFINED(pattern)) {
     var searcher = pattern[searchSymbol];
     if (!IS_UNDEFINED(searcher)) {
       return %_Call(searcher, pattern, this);
     }
   }
 
   var subject = TO_STRING(this);
-  var regexp = new GlobalRegExp(pattern);
+
+  // Equivalent to RegExpCreate (ES#sec-regexpcreate)
+  var regexp = %NewObject(GlobalRegExp, GlobalRegExp);
+  RegExpInitialize(regexp, pattern);
   return %_Call(regexp[searchSymbol], regexp, subject);
 }
 
 
 // ECMA-262 section 15.5.4.13
 function StringSlice(start, end) {
   CHECK_OBJECT_COERCIBLE(this, "String.prototype.slice");
 
   var s = TO_STRING(this);
   var s_len = s.length;
@@ skipping 552 matching lines @@
   to.StringLastIndexOf = StringLastIndexOf;
   to.StringMatch = StringMatchJS;
   to.StringReplace = StringReplace;
   to.StringSlice = StringSlice;
   to.StringSplit = StringSplitJS;
   to.StringSubstr = StringSubstr;
   to.StringSubstring = StringSubstring;
 });
 
 })