Maintain the invariant that the pattern string in an atom regexp is always ...

src/runtime.cc

 // Copyright 2006-2009 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 2001 matching lines @@
 
 
   void IncrementCharacterCount(int by) {
     if (character_count_ > String::kMaxLength - by) {
       V8::FatalProcessOutOfMemory("String.replace result too large.");
     }
     character_count_ += by;
   }
 
   Handle<JSArray> GetParts() {
-    Handle<JSArray> result =
-        Factory::NewJSArrayWithElements(array_builder_.array());
-    result->set_length(Smi::FromInt(array_builder_.length()));
-    return result;
+    return array_builder_.ToJSArray();
   }
 
  private:
   Handle<String> NewRawAsciiString(int size) {
     CALL_HEAP_FUNCTION(Heap::AllocateRawAsciiString(size), String);
   }
 
 
   Handle<String> NewRawTwoByteString(int size) {
     CALL_HEAP_FUNCTION(Heap::AllocateRawTwoByteString(size), String);
@@ skipping 554 matching lines @@
 
   return StringReplaceRegExpWithString(subject,
                                        regexp,
                                        replacement,
                                        last_match_info);
 }
 
 
 // Perform string match of pattern on subject, starting at start index.
 // Caller must ensure that 0 <= start_index <= sub->length(),
-// and should check that pat->length() + start_index <= sub->length()
+// and should check that pat->length() + start_index <= sub->length().
 int Runtime::StringMatch(Handle<String> sub,
                          Handle<String> pat,
                          int start_index) {
   ASSERT(0 <= start_index);
   ASSERT(start_index <= sub->length());
 
   int pattern_length = pat->length();
   if (pattern_length == 0) return start_index;
 
   int subject_length = sub->length();
@@ skipping 577 matching lines @@
   if (result_array->HasFastElements()) {
     result_elements =
         Handle<FixedArray>(FixedArray::cast(result_array->elements()));
   } else {
     result_elements = Factory::NewFixedArrayWithHoles(16);
   }
   FixedArrayBuilder builder(result_elements);
 
   if (regexp->TypeTag() == JSRegExp::ATOM) {
     Handle<String> pattern(
         String::cast(regexp->DataAt(JSRegExp::kAtomPatternIndex)));

[Lasse Reichstein, 2010/11/30 11:34:38]

Add an ASSERT(pattern->IsFlat()); somewhere, just to be pedantic.

[sandholm, 2010/11/30 11:55:24]

Done.

-    if (!pattern->IsFlat()) FlattenString(pattern);
     if (SearchStringMultiple(subject, pattern, last_match_info, &builder)) {
       return *builder.ToJSArray(result_array);
     }
     return Heap::null_value();
   }
 
   ASSERT_EQ(regexp->TypeTag(), JSRegExp::IRREGEXP);
 
   RegExpImpl::IrregexpResult result;
   if (regexp->CaptureCount() == 0) {
@@ skipping 7115 matching lines @@
   } else {
     // Handle last resort GC and make sure to allow future allocations
     // to grow the heap without causing GCs (if possible).
     Counters::gc_last_resort_from_js.Increment();
     Heap::CollectAllGarbage(false);
   }
 }
 
 
 } }  // namespace v8::internal