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diff --git a/gfx/layers/d3d11/FenceD3D11.h b/gfx/layers/d3d11/FenceD3D11.h
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef MOZILLA_GFX_FenceD3D11_H
+#define MOZILLA_GFX_FenceD3D11_H
+
+#include <unordered_map>
+
+#include "mozilla/gfx/FileHandleWrapper.h"
+#include "nsISupportsImpl.h"
+
+struct ID3D11Device;
+struct ID3D11Fence;
+
+namespace mozilla {
+
+namespace layers {
+
+//
+// A class for wrapping ID3D11Fence.
+//
+// The class can be used for singaling fence and waiting fence. When the class
+// is created by Create(), it can be used for singaling fence and waiting
+// fence. When the class is created by CreateFromHandle() it can be used only
+// for waiting fence.
+//
+// There is a case that ID3D12Fence is used for fence signaling. In this case,
+// the class can be used for waitng fence by using CreateFromHandle().
+//
+// IncrementAndSignal() is used for signaling fence. The fence will be updated
+// after all previous work has completed.
+//
+// For waiting fence, Update() is used to update the target value of the
+// waiting. Wait() is then used to wait for the fence.
+//
+class FenceD3D11 final {
+ public:
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(FenceD3D11);
+
+  static RefPtr<FenceD3D11> Create(ID3D11Device* aDevice);
+  static RefPtr<FenceD3D11> CreateFromHandle(
+      RefPtr<gfx::FileHandleWrapper> aHandle);
+
+  // Check if ID3D11Device suppors ID3D11Fence creation.
+  static bool IsSupported(ID3D11Device* aDevice);
+
+  // Updates mSignalFence to incremented value after all previous work has
+  // completed. Used only when FenceD3D11 is created by FenceD3D11::Create().
+  bool IncrementAndSignal();
+
+  // Update FenceValue to the specified value.
+  // Used only when FenceD3D11 is created by FenceD3D11::CreateFromHandle().
+  void Update(uint64_t aFenceValue);
+
+  // Wait for fence until it reaches or exceeds mFenceValue.
+  bool Wait(ID3D11Device* aDevice);
+
+  uint64_t GetFenceValue() const { return mFenceValue; }
+
+  gfx::FenceInfo GetFenceInfo() const;
+
+  const RefPtr<gfx::FileHandleWrapper> mHandle;
+
+ protected:
+  explicit FenceD3D11(RefPtr<gfx::FileHandleWrapper>& aHandle);
+  ~FenceD3D11();
+
+  // Device that is used for creating mSignalFence.
+  RefPtr<ID3D11Device> mDevice;
+  // Fence that is used for updating fence value.
+  // Valid only when created with FenceD3D11::Create().
+  RefPtr<ID3D11Fence> mSignalFence;
+  uint64_t mFenceValue = 0;
+  // Fences that are used for waiting.
+  // They are opened for each D3D11 device that the fence is waited on.
+  // XXX change to LRU cache
+  std::unordered_map<const ID3D11Device*, RefPtr<ID3D11Fence>> mWaitFenceMap;
+};
+
+}  // namespace layers
+}  // namespace mozilla
+
+#endif  // MOZILLA_GFX_FenceD3D11_H