Heap profiler: implement diffing of snapshots.

src/heap-profiler.h

 // Copyright 2009 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 20 matching lines @@
 #include "zone-inl.h"
 
 namespace v8 {
 namespace internal {
 
 #ifdef ENABLE_LOGGING_AND_PROFILING
 
 class HeapSnapshot;
 class HeapSnapshotsCollection;
 
-#endif
+#define HEAP_PROFILE(Call)                             \
+  do {                                                 \
+    if (v8::internal::HeapProfiler::is_profiling()) {  \
+      v8::internal::HeapProfiler::Call;                \
+    }                                                  \
+  } while (false)
+#else
+#define HEAP_PROFILE(Call) ((void) 0)
+#endif  // ENABLE_LOGGING_AND_PROFILING
 
 // The HeapProfiler writes data to the log files, which can be postprocessed
 // to generate .hp files for use by the GHC/Valgrind tool hp2ps.
 class HeapProfiler {
  public:
   static void Setup();
   static void TearDown();
 
 #ifdef ENABLE_LOGGING_AND_PROFILING
   static HeapSnapshot* TakeSnapshot(const char* name);
   static HeapSnapshot* TakeSnapshot(String* name);
   static int GetSnapshotsCount();
   static HeapSnapshot* GetSnapshot(int index);
   static HeapSnapshot* FindSnapshot(unsigned uid);
 
+  static void ObjectMoveEvent(Address from, Address to);
+
+  static INLINE(bool is_profiling()) {
+    return singleton_ != NULL && singleton_->snapshots_->is_tracking_objects();
+  }
+
   // Obsolete interface.
   // Write a single heap sample to the log file.
   static void WriteSample();
 
  private:
   HeapProfiler();
   ~HeapProfiler();
   HeapSnapshot* TakeSnapshotImpl(const char* name);
   HeapSnapshot* TakeSnapshotImpl(String* name);
 
@@ skipping 233 matching lines @@
  private:
   static void DoRecordJSObjectAllocation(Object* obj);
   static bool can_log_;
 };
 
 #endif  // ENABLE_LOGGING_AND_PROFILING
 
 } }  // namespace v8::internal
 
 #endif  // V8_HEAP_PROFILER_H_