Show names for the strong roots in heap snapshot.

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 835 matching lines @@
   void CountReference(HeapThing from, HeapThing to,
                       int* prev_children_count = NULL,
                       int* prev_retainers_count = NULL);
 
   int entries_count() { return entries_count_; }
   int total_children_count() { return total_children_count_; }
   int total_retainers_count() { return total_retainers_count_; }
 
   static HeapEntry* const kHeapEntryPlaceholder;
 
+  static uint32_t Hash(HeapThing thing) {
+    return ComputeIntegerHash(
+        static_cast<uint32_t>(reinterpret_cast<uintptr_t>(thing)),
+        v8::internal::kZeroHashSeed);
+  }
+  static bool HeapThingsMatch(HeapThing key1, HeapThing key2) {
+    return key1 == key2;
+  }
+
  private:
   struct EntryInfo {
     EntryInfo(HeapEntry* entry, HeapEntriesAllocator* allocator)
         : entry(entry),
           allocator(allocator),
           children_count(0),
           retainers_count(0) {
     }
     HeapEntry* entry;
     HeapEntriesAllocator* allocator;
     int children_count;
     int retainers_count;
   };
 
   static inline void AllocateHeapEntryForMapEntry(HashMap::Entry* map_entry);
 
-  static uint32_t Hash(HeapThing thing) {
-    return ComputeIntegerHash(
-        static_cast<uint32_t>(reinterpret_cast<uintptr_t>(thing)),
-        v8::internal::kZeroHashSeed);
-  }
-  static bool HeapThingsMatch(HeapThing key1, HeapThing key2) {
-    return key1 == key2;
-  }
-
   HashMap entries_;
   int entries_count_;
   int total_children_count_;
   int total_retainers_count_;
 
   friend class HeapObjectsSet;
 
   DISALLOW_COPY_AND_ASSIGN(HeapEntriesMap);
 };
 
@@ skipping 127 matching lines @@
                             int field_offset = -1);
   void SetPropertyShortcutReference(HeapObject* parent_obj,
                                     HeapEntry* parent,
                                     String* reference_name,
                                     Object* child);
   void SetUserGlobalReference(Object* window);
   void SetRootGcRootsReference();
   void SetGcRootsReference(VisitorSynchronization::SyncTag tag);
   void SetGcSubrootReference(
       VisitorSynchronization::SyncTag tag, bool is_weak, Object* child);
+  const char* GetGcSubrootName(Object* object);

[mnaganov (inactive), 2012/04/19 13:52:29]

If it deals only with strong roots, perhaps call it 'GetStrongGcSubrootName'?

[alexeif, 2012/04/19 15:27:43]

Done.

   void SetObjectName(HeapObject* object);
   void TagObject(Object* obj, const char* tag);
 
   HeapEntry* GetEntry(Object* obj);
 
   static inline HeapObject* GetNthGcSubrootObject(int delta);
   static inline int GetGcSubrootOrder(HeapObject* subroot);
 
   Heap* heap_;
   HeapSnapshot* snapshot_;
   HeapSnapshotsCollection* collection_;
   SnapshottingProgressReportingInterface* progress_;
   SnapshotFillerInterface* filler_;
   HeapObjectsSet objects_tags_;
+  HashMap gc_subroot_names_;

[mnaganov (inactive), 2012/04/19 13:52:29]

Why are you using a generic HashMap? HeapObjectsSet can associate heap objects
with tags.

[alexeif, 2012/04/19 15:27:43]

Done.

 
   static HeapObject* const kGcRootsObject;
   static HeapObject* const kFirstGcSubrootObject;
   static HeapObject* const kLastGcSubrootObject;
 
   friend class IndexedReferencesExtractor;
   friend class GcSubrootsEnumerator;
   friend class RootsReferencesExtractor;
 
   DISALLOW_COPY_AND_ASSIGN(V8HeapExplorer);
@@ skipping 140 matching lines @@
 
   friend class HeapSnapshotJSONSerializerEnumerator;
   friend class HeapSnapshotJSONSerializerIterator;
 
   DISALLOW_COPY_AND_ASSIGN(HeapSnapshotJSONSerializer);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_PROFILE_GENERATOR_H_