Faster string.replace with regexp pattern.

src/jsregexp.h

 // 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 18 matching lines @@
 #define V8_JSREGEXP_H_
 
 namespace v8 { namespace internal {
 
 
 class RegExpMacroAssembler;
 
 
 class RegExpImpl {
  public:
+  static inline bool UseNativeRegexp() {
+#ifdef ARM
+    return false;
+#else
+    return FLAG_regexp_native;
+#endif
+  }
   // Creates a regular expression literal in the old space.
   // This function calls the garbage collector if necessary.
   static Handle<Object> CreateRegExpLiteral(Handle<JSFunction> constructor,
                                             Handle<String> pattern,
                                             Handle<String> flags,
                                             bool* has_pending_exception);
 
   // Returns a string representation of a regular expression.
   // Implements RegExp.prototype.toString, see ECMA-262 section 15.10.6.4.
   // This function calls the garbage collector if necessary.
@@ skipping 61 matching lines @@
   static Handle<String> StringToTwoByte(Handle<String> pattern);
   static Handle<String> CachedStringToTwoByte(Handle<String> pattern);
 
   // Offsets in the lastMatchInfo array.
   static const int kLastCaptureCount = 0;
   static const int kLastSubject = 1;
   static const int kLastInput = 2;
   static const int kFirstCapture = 1;
   static const int kLastMatchOverhead = 3;
 
+  // Used to access the lastMatchInfo array.
   static int GetCapture(FixedArray* array, int index) {
     return Smi::cast(array->get(index + kFirstCapture))->value();
   }
 
   static void SetLastCaptureCount(FixedArray* array, int to) {
     array->set(kLastCaptureCount, Smi::FromInt(to));
   }
 
   static void SetLastSubject(FixedArray* array, String* to) {
     int capture_count = GetLastCaptureCount(array);
     array->set(capture_count + kLastSubject, to);
   }
 
   static void SetLastInput(FixedArray* array, String* to) {
     int capture_count = GetLastCaptureCount(array);
     array->set(capture_count + kLastInput, to);
   }
 
   static void SetCapture(FixedArray* array, int index, int to) {
     array->set(index + kFirstCapture, Smi::FromInt(to));
   }
 
- private:
-  static String* last_ascii_string_;
-  static String* two_byte_cached_string_;
+  static int GetLastCaptureCount(FixedArray* array) {
+    return Smi::cast(array->get(kLastCaptureCount))->value();
+  }
 
-  static bool EnsureCompiledIrregexp(Handle<JSRegExp> re, bool is_ascii);
-
+  // For acting on the JSRegExp data FixedArray.
   static int IrregexpMaxRegisterCount(FixedArray* re);
   static void SetIrregexpMaxRegisterCount(FixedArray* re, int value);
   static int IrregexpNumberOfCaptures(FixedArray* re);
   static int IrregexpNumberOfRegisters(FixedArray* re);
   static ByteArray* IrregexpByteCode(FixedArray* re, bool is_ascii);
   static Code* IrregexpNativeCode(FixedArray* re, bool is_ascii);
 
+ private:
+  static String* last_ascii_string_;
+  static String* two_byte_cached_string_;
+
+  static bool EnsureCompiledIrregexp(Handle<JSRegExp> re, bool is_ascii);
+
+
   // On a successful match, the result is a JSArray containing
   // captured positions. On a failure, the result is the null value.
   // Returns an empty handle in case of an exception.
   static Handle<Object> IrregexpExecOnce(Handle<FixedArray> regexp,
                                          int num_captures,
                                          Handle<JSArray> lastMatchInfo,
                                          Handle<String> subject16,
                                          int previous_index,
                                          int* ovector,
                                          int ovector_length);
 
   // Set the subject cache.  The previous string buffer is not deleted, so the
   // caller should ensure that it doesn't leak.
   static void SetSubjectCache(String* subject,
                               char* utf8_subject,
                               int uft8_length,
                               int character_position,
                               int utf8_position);
 
-  // Used to access the lastMatchInfo array.
-  static int GetLastCaptureCount(FixedArray* array) {
-    return Smi::cast(array->get(kLastCaptureCount))->value();
-  }
   // A one element cache of the last utf8_subject string and its length.  The
   // subject JS String object is cached in the heap.  We also cache a
   // translation between position and utf8 position.
   static char* utf8_subject_cache_;
   static int utf8_length_cache_;
   static int utf8_position_;
   static int character_position_;
 };
 
 
@@ skipping 1192 matching lines @@
                                    Handle<String> pattern,
                                    bool is_ascii);
 
   static void DotPrint(const char* label, RegExpNode* node, bool ignore_case);
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_JSREGEXP_H_