Detailed heap snapshot usability improvement.

src/profile-generator.h

 // Copyright 2011 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 1008 matching lines @@
   static HeapObject* const kFirstGcSubrootObject;
   static HeapObject* const kLastGcSubrootObject;
 
   friend class IndexedReferencesExtractor;
   friend class GcSubrootsEnumerator;
   friend class RootsReferencesExtractor;
 
   DISALLOW_COPY_AND_ASSIGN(V8HeapExplorer);
 };
 
+class NativeGroupRetainedObjectInfo;
 
 // An implementation of retained native objects extractor.
 class NativeObjectsExplorer : public HeapEntriesAllocator {
  public:
   NativeObjectsExplorer(HeapSnapshot* snapshot,
                       SnapshottingProgressReportingInterface* progress);
   virtual ~NativeObjectsExplorer();
   virtual HeapEntry* AllocateEntry(
       HeapThing ptr, int children_count, int retainers_count);
   void AddRootEntries(SnapshotFillerInterface* filler);
   int EstimateObjectsCount();
   bool IterateAndExtractReferences(SnapshotFillerInterface* filler);
 
  private:
   void FillRetainedObjects();
   List<HeapObject*>* GetListMaybeDisposeInfo(v8::RetainedObjectInfo* info);
   void SetNativeRootReference(v8::RetainedObjectInfo* info);
-  void SetRootNativesRootReference();
+  void SetRootNativeRootsReference();
   void SetWrapperNativeReferences(HeapObject* wrapper,
                                       v8::RetainedObjectInfo* info);
   void VisitSubtreeWrapper(Object** p, uint16_t class_id);
 
   static uint32_t InfoHash(v8::RetainedObjectInfo* info) {
     return ComputeIntegerHash(static_cast<uint32_t>(info->GetHash()),
                               v8::internal::kZeroHashSeed);
   }
   static bool RetainedInfosMatch(void* key1, void* key2) {
     return key1 == key2 ||
         (reinterpret_cast<v8::RetainedObjectInfo*>(key1))->IsEquivalent(
             reinterpret_cast<v8::RetainedObjectInfo*>(key2));
   }
+  INLINE(static bool StringsMatch(void* key1, void* key2)) {
+    return strcmp(reinterpret_cast<char*>(key1),
+                  reinterpret_cast<char*>(key2)) == 0;
+  }
+
+  NativeGroupRetainedObjectInfo* FindOrAddGroupInfo(const char* label);
 
   HeapSnapshot* snapshot_;
   HeapSnapshotsCollection* collection_;
   SnapshottingProgressReportingInterface* progress_;
   bool embedder_queried_;
   HeapObjectsSet in_groups_;
   // RetainedObjectInfo* -> List<HeapObject*>*
   HashMap objects_by_info_;
+  HashMap native_groups_;
   // Used during references extraction.
   SnapshotFillerInterface* filler_;
 
   static HeapThing const kNativesRootObject;
 
   friend class GlobalHandlesExtractor;
 
   DISALLOW_COPY_AND_ASSIGN(NativeObjectsExplorer);
 };
 
@@ skipping 78 matching lines @@
 
   friend class HeapSnapshotJSONSerializerEnumerator;
   friend class HeapSnapshotJSONSerializerIterator;
 
   DISALLOW_COPY_AND_ASSIGN(HeapSnapshotJSONSerializer);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_PROFILE_GENERATOR_H_