Add counters that automatically track object sizes and counts.

src/heap.h

 // Copyright 2012 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 1582 matching lines @@
   // Global inline caching age: it is incremented on some GCs after context
   // disposal. We use it to flush inline caches.
   int global_ic_age() {
     return global_ic_age_;
   }
 
   void AgeInlineCaches() {
     global_ic_age_ = (global_ic_age_ + 1) & SharedFunctionInfo::ICAgeBits::kMax;
   }
 
+  void RecordObjectStats(InstanceType type, size_t size) {
+    ASSERT(type <= LAST_TYPE);
+    object_counts_[type]++;
+    object_sizes_[type] += size;
+  }
+
+  void CheckpointObjectStats();
+
  private:
   Heap();
 
   // This can be calculated directly from a pointer to the heap; however, it is
   // more expedient to get at the isolate directly from within Heap methods.
   Isolate* isolate_;
 
   Object* roots_[kRootListLength];
 
   intptr_t code_range_size_;
@@ skipping 373 matching lines @@
 
     int heap_size_mb = static_cast<int>(SizeOfObjects() / MB);
     return heap_size_mb / kMbPerMs;
   }
 
   // Returns true if no more GC work is left.
   bool IdleGlobalGC();
 
   void AdvanceIdleIncrementalMarking(intptr_t step_size);
 
+  void ClearObjectStats(bool clear_last_time_stats = false);
 
   static const int kInitialSymbolTableSize = 2048;
   static const int kInitialEvalCacheSize = 64;
   static const int kInitialNumberStringCacheSize = 256;
 
+  // Object counts and used memory by InstanceType
+  size_t object_counts_[LAST_TYPE + 1];
+  size_t object_counts_last_time_[LAST_TYPE + 1];
+  size_t object_sizes_[LAST_TYPE + 1];
+  size_t object_sizes_last_time_[LAST_TYPE + 1];
+
   // Maximum GC pause.
   int max_gc_pause_;
 
   // Maximum size of objects alive after GC.
   intptr_t max_alive_after_gc_;
 
   // Minimal interval between two subsequent collections.
   int min_in_mutator_;
 
   // Size of objects alive after last GC.
@@ skipping 690 matching lines @@
   AssertNoAllocation no_alloc;  // i.e. no gc allowed.
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(PathTracer);
 };
 #endif  // DEBUG || LIVE_OBJECT_LIST
 
 } }  // namespace v8::internal
 
 #endif  // V8_HEAP_H_