Attempt to make \b\w+ faster. Slight performance increase on, e.g., string unpacking.

src/parser.cc

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 353 matching lines @@
 class RegExpBuilder: public ZoneObject {
  public:
   RegExpBuilder();
   void AddCharacter(uc16 character);
   // "Adds" an empty expression. Does nothing except consume a
   // following quantifier
   void AddEmpty();
   void AddAtom(RegExpTree* tree);
   void AddAssertion(RegExpTree* tree);
   void NewAlternative();  // '|'
-  void AddQuantifierToAtom(int min, int max, bool is_greedy);
+  void AddQuantifierToAtom(int min, int max, RegExpQuantifier::Type type);
   RegExpTree* ToRegExp();
  private:
   void FlushCharacters();
   void FlushText();
   void FlushTerms();
   bool pending_empty_;
   ZoneList<uc16>* characters_;
   BufferedZoneList<RegExpTree, 2> terms_;
   BufferedZoneList<RegExpTree, 2> text_;
   BufferedZoneList<RegExpTree, 2> alternatives_;
@@ skipping 111 matching lines @@
   if (num_alternatives == 0) {
     return RegExpEmpty::GetInstance();
   }
   if (num_alternatives == 1) {
     return alternatives_.last();
   }
   return new RegExpDisjunction(alternatives_.GetList());
 }
 
 
-void RegExpBuilder::AddQuantifierToAtom(int min, int max, bool is_greedy) {
+void RegExpBuilder::AddQuantifierToAtom(int min,
+                                        int max,
+                                        RegExpQuantifier::Type type) {
   if (pending_empty_) {
     pending_empty_ = false;
     return;
   }
   RegExpTree* atom;
   if (characters_ != NULL) {
     ASSERT(last_added_ == ADD_CHAR);
     // Last atom was character.
     Vector<const uc16> char_vector = characters_->ToConstVector();
     int num_chars = char_vector.length();
@@ skipping 19 matching lines @@
         return;
       }
       terms_.Add(atom);
       return;
     }
   } else {
     // Only call immediately after adding an atom or character!
     UNREACHABLE();
     return;
   }
-  terms_.Add(new RegExpQuantifier(min, max, is_greedy, atom));
+  terms_.Add(new RegExpQuantifier(min, max, type, atom));
   LAST(ADD_TERM);
 }
 
 
 class RegExpParser {
  public:
   RegExpParser(FlatStringReader* in,
                Handle<String>* error,
                bool multiline_mode);
   RegExpTree* ParsePattern();
@@ skipping 3714 matching lines @@
           ReportError(CStrVector("numbers out of order in {} quantifier.")
                       CHECK_FAILED);
         }
         break;
       } else {
         continue;
       }
     default:
       continue;
     }
-    bool is_greedy = true;
+    RegExpQuantifier::Type type = RegExpQuantifier::GREEDY;
     if (current() == '?') {
-      is_greedy = false;
+      type = RegExpQuantifier::NON_GREEDY;
+      Advance();
+    } else if (FLAG_regexp_possessive_quantifier && current() == '+') {
+      // FLAG_regexp_possessive_quantifier is a debug-only flag.
+      type = RegExpQuantifier::POSSESSIVE;
       Advance();
     }
-    builder->AddQuantifierToAtom(min, max, is_greedy);
+    builder->AddQuantifierToAtom(min, max, type);
   }
 }
 
 class SourceCharacter {
  public:
   static bool Is(uc32 c) {
     switch (c) {
       // case ']': case '}':
       // In spidermonkey and jsc these are treated as source characters
       // so we do too.
@@ skipping 493 matching lines @@
                        start_position,
                        is_expression);
   return result;
 }
 
 
 #undef NEW
 
 
 } }  // namespace v8::internal