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diff --git a/deps/v8/src/objects/tagged-field.h b/deps/v8/src/objects/tagged-field.h
new file mode 100644
index 0000000000..fbaaee5930
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+++ b/deps/v8/src/objects/tagged-field.h
@@ -0,0 +1,76 @@
+// Copyright 2019 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef V8_OBJECTS_TAGGED_FIELD_H_
+#define V8_OBJECTS_TAGGED_FIELD_H_
+
+#include "src/common/globals.h"
+
+#include "src/objects/objects.h"
+#include "src/objects/tagged-value.h"
+
+namespace v8 {
+namespace internal {
+
+// This helper static class represents a tagged field of type T at offset
+// kFieldOffset inside some host HeapObject.
+// For full-pointer mode this type adds no overhead but when pointer
+// compression is enabled such class allows us to use proper decompression
+// function depending on the field type.
+template <typename T, int kFieldOffset = 0>
+class TaggedField : public AllStatic {
+ public:
+  static_assert(std::is_base_of<Object, T>::value ||
+                    std::is_same<MapWord, T>::value ||
+                    std::is_same<MaybeObject, T>::value,
+                "T must be strong or weak tagged type or MapWord");
+
+  // True for Smi fields.
+  static constexpr bool kIsSmi = std::is_base_of<Smi, T>::value;
+
+  // True for HeapObject and MapWord fields. The latter may look like a Smi
+  // if it contains forwarding pointer but still requires tagged pointer
+  // decompression.
+  static constexpr bool kIsHeapObject =
+      std::is_base_of<HeapObject, T>::value || std::is_same<MapWord, T>::value;
+
+  static inline Address address(HeapObject host, int offset = 0);
+
+  static inline T load(HeapObject host, int offset = 0);
+  static inline T load(Isolate* isolate, HeapObject host, int offset = 0);
+
+  static inline void store(HeapObject host, T value);
+  static inline void store(HeapObject host, int offset, T value);
+
+  static inline T Relaxed_Load(HeapObject host, int offset = 0);
+  static inline T Relaxed_Load(Isolate* isolate, HeapObject host,
+                               int offset = 0);
+
+  static inline void Relaxed_Store(HeapObject host, T value);
+  static inline void Relaxed_Store(HeapObject host, int offset, T value);
+
+  static inline T Acquire_Load(HeapObject host, int offset = 0);
+  static inline T Acquire_Load(Isolate* isolate, HeapObject host,
+                               int offset = 0);
+
+  static inline void Release_Store(HeapObject host, T value);
+  static inline void Release_Store(HeapObject host, int offset, T value);
+
+  static inline Tagged_t Release_CompareAndSwap(HeapObject host, T old,
+                                                T value);
+
+ private:
+  static inline Tagged_t* location(HeapObject host, int offset = 0);
+
+  template <typename TOnHeapAddress>
+  static inline Address tagged_to_full(TOnHeapAddress on_heap_addr,
+                                       Tagged_t tagged_value);
+
+  static inline Tagged_t full_to_tagged(Address value);
+};
+
+}  // namespace internal
+}  // namespace v8
+
+#endif  // V8_OBJECTS_TAGGED_FIELD_H_