Do not try to serialize VM objects, these are read only canonical objects and should be referred to…

vm/symbols.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/symbols.h"
 
 #include "vm/isolate.h"
 #include "vm/object.h"
 #include "vm/object_store.h"
 #include "vm/raw_object.h"
 #include "vm/unicode.h"
 #include "vm/visitor.h"
 
 namespace dart {
 
 RawString* Symbols::predefined_[Symbols::kMaxPredefined];
 
 // Turn off population of symbols in the VM symbol table, so that we
 // don't find these symbols while doing a Symbols::New(...).
-#if 0
 static const char* names[] = {
   NULL,
 
 #define DEFINE_SYMBOL_LITERAL(symbol, literal)                                 \
   literal,
 PREDEFINED_SYMBOLS_LIST(DEFINE_SYMBOL_LITERAL)
 #undef DEFINE_SYMBOL_LITERAL
 };
-#endif
 
 
 void Symbols::InitOnce(Isolate* isolate) {
   // Should only be run by the vm isolate.
   ASSERT(isolate == Dart::vm_isolate());
 
   // Create and setup a symbol table in the vm isolate.
   SetupSymbolTable(isolate);
 
   // Turn off population of symbols in the VM symbol table, so that we
   // don't find these symbols while doing a Symbols::New(...).
-#if 0
   // Create all predefined symbols.
   ASSERT((sizeof(names) / sizeof(const char*)) == kMaxPredefined);
   const Array& symbol_table =
       Array::Handle(isolate->object_store()->symbol_table());
   OneByteString& str = OneByteString::Handle();
 
   for (intptr_t i = 1; i < kMaxPredefined; i++) {
     str = OneByteString::New(names[i], Heap::kOld);
     Add(symbol_table, str);
     predefined_[i] = str.raw();
   }
-#endif
 }
 
 
 void Symbols::SetupSymbolTable(Isolate* isolate) {
   ASSERT(isolate != NULL);
 
   // Setup the symbol table used within the String class.
   const int initial_size = (isolate == Dart::vm_isolate()) ?
       kInitialVMIsolateSymtabSize : kInitialSymtabSize;
   const Array& array = Array::Handle(Array::New(initial_size + 1));
@@ skipping 226 matching lines @@
 
   String& symbol = String::Handle();
   symbol ^= symbol_table.At(index);
   while (!symbol.IsNull() && !symbol.Equals(str, begin_index, len)) {
     index = (index + 1) % table_size;  // Move to next element.
     symbol ^= symbol_table.At(index);
   }
   return index;  // Index of symbol if found or slot into which to add symbol.
 }
 
+
+intptr_t Symbols::LookupVMSymbol(RawObject* obj) {
+  for (intptr_t i = 1;  i < kMaxPredefined; i++) {
+    if (predefined_[i] == obj) {
+      return (i + Object::kMaxId);
+    }
+  }
+  return Object::kInvalidIndex;
+}
+
+
+RawObject* Symbols::GetVMSymbol(intptr_t object_id) {
+  ASSERT(IsVMSymbolId(object_id));
+  intptr_t i = (object_id - Object::kMaxId);
+  return (i > 0 && i < kMaxPredefined) ? predefined_[i] : Object::null();
+}
+
 }  // namespace dart