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diff --git a/libartbase/base/bit_field.h b/libartbase/base/bit_field.h
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+++ b/libartbase/base/bit_field.h
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+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ART_LIBARTBASE_BASE_BIT_FIELD_H_
+#define ART_LIBARTBASE_BASE_BIT_FIELD_H_
+
+#include <android-base/logging.h>
+
+#include "globals.h"
+
+namespace art {
+
+static constexpr uintptr_t kUintPtrTOne = 1U;
+
+// BitField is a template for encoding and decoding a bit field inside
+// an unsigned machine word.
+template<typename T, size_t kPosition, size_t kSize>
+class BitField {
+ public:
+  typedef T value_type;
+  static constexpr size_t position = kPosition;
+  static constexpr size_t size = kSize;
+
+  static_assert(position < sizeof(uintptr_t) * kBitsPerByte, "Invalid position.");
+  static_assert(size != 0u, "Invalid size.");
+  static_assert(size <= sizeof(uintptr_t) * kBitsPerByte, "Invalid size.");
+  static_assert(size + position <= sizeof(uintptr_t) * kBitsPerByte, "Invalid position + size.");
+
+  // Tells whether the provided value fits into the bit field.
+  static bool IsValid(T value) {
+    return (static_cast<uintptr_t>(value) & ~((kUintPtrTOne << size) - 1)) == 0;
+  }
+
+  // Returns a uword mask of the bit field.
+  static uintptr_t Mask() {
+    return (kUintPtrTOne << size) - 1;
+  }
+
+  // Returns a uword mask of the bit field which can be applied directly to
+  // the raw unshifted bits.
+  static uintptr_t MaskInPlace() {
+    return ((kUintPtrTOne << size) - 1) << position;
+  }
+
+  // Returns the shift count needed to right-shift the bit field to
+  // the least-significant bits.
+  static int Shift() {
+    return position;
+  }
+
+  // Returns the size of the bit field.
+  static int BitSize() {
+    return size;
+  }
+
+  // Returns a uword with the bit field value encoded.
+  static uintptr_t Encode(T value) {
+    DCHECK(IsValid(value));
+    return static_cast<uintptr_t>(value) << position;
+  }
+
+  // Extracts the bit field from the value.
+  static T Decode(uintptr_t value) {
+    return static_cast<T>((value >> position) & ((kUintPtrTOne << size) - 1));
+  }
+
+  // Returns a uword with the bit field value encoded based on the
+  // original value. Only the bits corresponding to this bit field
+  // will be changed.
+  static uintptr_t Update(T value, uintptr_t original) {
+    DCHECK(IsValid(value));
+    return (static_cast<uintptr_t>(value) << position) |
+        (~MaskInPlace() & original);
+  }
+};
+
+}  // namespace art
+
+#endif  // ART_LIBARTBASE_BASE_BIT_FIELD_H_