Serializer: collect and output memory statistics.

src/snapshot/serialize.h

Index: src/snapshot/serialize.h
diff --git a/src/snapshot/serialize.h b/src/snapshot/serialize.h
index 82187663a8a20857008dd459b8a3476bb85e635c..39f403b0d8bd30d193d552381e568e51a526015c 100644
--- a/src/snapshot/serialize.h
+++ b/src/snapshot/serialize.h
@@ -617,6 +617,10 @@ class Serializer : public SerializerDeserializer {
   BackReferenceMap* back_reference_map() { return &back_reference_map_; }
   RootIndexMap* root_index_map() { return &root_index_map_; }
 
+  void CountInstanceType(InstanceType instance_type) {
+    instance_type_count_[instance_type]++;
+  }
+
  protected:
   class ObjectSerializer : public ObjectVisitor {
    public:
@@ -718,6 +722,8 @@ class Serializer : public SerializerDeserializer {
 
   SnapshotByteSink* sink() const { return sink_; }
 
+  void OutputStatistics(const char* name);
+
   Isolate* isolate_;
 
   SnapshotByteSink* sink_;
@@ -746,6 +752,9 @@ class Serializer : public SerializerDeserializer {
 
   List<byte> code_buffer_;
 
+  static const int kInstanceTypes = 256;
+  int* instance_type_count_;
+
   DISALLOW_COPY_AND_ASSIGN(Serializer);
 };
 
@@ -761,6 +770,8 @@ class PartialSerializer : public Serializer {
     InitializeCodeAddressMap();
   }
 
+  ~PartialSerializer() { OutputStatistics("PartialSerializer"); }
+
   // Serialize the objects reachable from a single object pointer.
   void Serialize(Object** o);
   virtual void SerializeObject(HeapObject* o, HowToCode how_to_code,
@@ -803,6 +814,8 @@ class StartupSerializer : public Serializer {
     InitializeCodeAddressMap();
   }
 
+  ~StartupSerializer() { OutputStatistics("StartupSerializer"); }
+
   // The StartupSerializer has to serialize the root array, which is slightly
   // different.
   void VisitPointers(Object** start, Object** end) OVERRIDE;
@@ -859,6 +872,8 @@ class CodeSerializer : public Serializer {
     back_reference_map_.AddSourceString(source);
   }
 
+  ~CodeSerializer() { OutputStatistics("CodeSerializer"); }
+
   virtual void SerializeObject(HeapObject* o, HowToCode how_to_code,
                                WhereToPoint where_to_point, int skip) OVERRIDE;