third_party/blink/renderer/platform/instance_counters.h

/*
* Copyright (C) 2012 Google Inc. All rights reserved.
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#ifndef THIRD_PARTY_BLINK_RENDERER_PLATFORM_INSTANCE_COUNTERS_H_
#define THIRD_PARTY_BLINK_RENDERER_PLATFORM_INSTANCE_COUNTERS_H_

#include "third_party/blink/renderer/platform/platform_export.h"
#include "third_party/blink/renderer/platform/wtf/allocator.h"
#include "third_party/blink/renderer/platform/wtf/atomics.h"
#include "third_party/blink/renderer/platform/wtf/wtf.h"

namespace blink {

#define INSTANCE_COUNTERS_LIST(V) \
  V(AudioHandler)                 \
  V(Document)                     \
  V(Frame)                        \
  V(JSEventListener)              \
  V(LayoutObject)                 \
  V(MediaKeySession)              \
  V(MediaKeys)                    \
  V(Node)                         \
  V(Resource)                     \
  V(ScriptPromise)                \
  V(PausableObject)               \
  V(V8PerContextData)             \
  V(WorkerGlobalScope)            \
  V(UACSSResource)                \
  V(RTCPeerConnection)            \
  V(ResourceFetcher)              \
  V(AdSubframe)                   \
  V(DetachedScriptState)

class InstanceCounters {
  STATIC_ONLY(InstanceCounters);

 public:
  enum CounterType {
#define DECLARE_INSTANCE_COUNTER(name) k##name##Counter,
    INSTANCE_COUNTERS_LIST(DECLARE_INSTANCE_COUNTER)
#undef DECLARE_INSTANCE_COUNTER
        kCounterTypeLength
  };

  static inline void IncrementCounter(CounterType type) {
    // There are lots of nodes created. Atomic barriers or locks
    // should be avoided for the sake of performance. See crbug.com/641019
    if (type == kNodeCounter) {
      DCHECK(IsMainThread());
      ++counters_[kNodeCounter];
    } else {
      AtomicIncrement(&counters_[type]);
    }
  }

  static inline void DecrementCounter(CounterType type) {
    if (type == kNodeCounter) {
      DCHECK(IsMainThread());
      --counters_[kNodeCounter];
    } else {
      AtomicDecrement(&counters_[type]);
    }
  }

  PLATFORM_EXPORT static int CounterValue(CounterType);

 private:
  PLATFORM_EXPORT static int counters_[];
};

}  // namespace blink

#endif  // !defined(InstanceCounters_h)