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diff --git a/libartbase/base/atomic.h b/libartbase/base/atomic.h
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+/*
+ * Copyright (C) 2008 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_ATOMIC_H_
+#define ART_LIBARTBASE_BASE_ATOMIC_H_
+
+#include <stdint.h>
+#include <atomic>
+#include <limits>
+#include <vector>
+
+#include <android-base/logging.h>
+
+#include "base/macros.h"
+
+namespace art {
+
+template<typename T>
+class PACKED(sizeof(T)) Atomic : public std::atomic<T> {
+ public:
+  Atomic<T>() : std::atomic<T>(T()) { }
+
+  explicit Atomic<T>(T value) : std::atomic<T>(value) { }
+
+  // Load from memory without ordering or synchronization constraints.
+  T LoadRelaxed() const {
+    return this->load(std::memory_order_relaxed);
+  }
+
+  // Load from memory with acquire ordering.
+  T LoadAcquire() const {
+    return this->load(std::memory_order_acquire);
+  }
+
+  // Word tearing allowed, but may race.
+  // TODO: Optimize?
+  // There has been some discussion of eventually disallowing word
+  // tearing for Java data loads.
+  T LoadJavaData() const {
+    return this->load(std::memory_order_relaxed);
+  }
+
+  // Load from memory with a total ordering.
+  // Corresponds exactly to a Java volatile load.
+  T LoadSequentiallyConsistent() const {
+    return this->load(std::memory_order_seq_cst);
+  }
+
+  // Store to memory without ordering or synchronization constraints.
+  void StoreRelaxed(T desired_value) {
+    this->store(desired_value, std::memory_order_relaxed);
+  }
+
+  // Word tearing allowed, but may race.
+  void StoreJavaData(T desired_value) {
+    this->store(desired_value, std::memory_order_relaxed);
+  }
+
+  // Store to memory with release ordering.
+  void StoreRelease(T desired_value) {
+    this->store(desired_value, std::memory_order_release);
+  }
+
+  // Store to memory with a total ordering.
+  void StoreSequentiallyConsistent(T desired_value) {
+    this->store(desired_value, std::memory_order_seq_cst);
+  }
+
+  // Atomically replace the value with desired_value.
+  T ExchangeRelaxed(T desired_value) {
+    return this->exchange(desired_value, std::memory_order_relaxed);
+  }
+
+  // Atomically replace the value with desired_value.
+  T ExchangeSequentiallyConsistent(T desired_value) {
+    return this->exchange(desired_value, std::memory_order_seq_cst);
+  }
+
+  // Atomically replace the value with desired_value.
+  T ExchangeAcquire(T desired_value) {
+    return this->exchange(desired_value, std::memory_order_acquire);
+  }
+
+  // Atomically replace the value with desired_value.
+  T ExchangeRelease(T desired_value) {
+    return this->exchange(desired_value, std::memory_order_release);
+  }
+
+  // Atomically replace the value with desired_value if it matches the expected_value.
+  // Participates in total ordering of atomic operations. Returns true on success, false otherwise.
+  // If the value does not match, updates the expected_value argument with the value that was
+  // atomically read for the failed comparison.
+  bool CompareAndExchangeStrongSequentiallyConsistent(T* expected_value, T desired_value) {
+    return this->compare_exchange_strong(*expected_value, desired_value, std::memory_order_seq_cst);
+  }
+
+  // Atomically replace the value with desired_value if it matches the expected_value.
+  // Participates in total ordering of atomic operations. Returns true on success, false otherwise.
+  // If the value does not match, updates the expected_value argument with the value that was
+  // atomically read for the failed comparison.
+  bool CompareAndExchangeStrongAcquire(T* expected_value, T desired_value) {
+    return this->compare_exchange_strong(*expected_value, desired_value, std::memory_order_acquire);
+  }
+
+  // Atomically replace the value with desired_value if it matches the expected_value.
+  // Participates in total ordering of atomic operations. Returns true on success, false otherwise.
+  // If the value does not match, updates the expected_value argument with the value that was
+  // atomically read for the failed comparison.
+  bool CompareAndExchangeStrongRelease(T* expected_value, T desired_value) {
+    return this->compare_exchange_strong(*expected_value, desired_value, std::memory_order_release);
+  }
+
+  // Atomically replace the value with desired_value if it matches the expected_value.
+  // Participates in total ordering of atomic operations.
+  bool CompareAndSetStrongSequentiallyConsistent(T expected_value, T desired_value) {
+    return this->compare_exchange_strong(expected_value, desired_value, std::memory_order_seq_cst);
+  }
+
+  // The same, except it may fail spuriously.
+  bool CompareAndSetWeakSequentiallyConsistent(T expected_value, T desired_value) {
+    return this->compare_exchange_weak(expected_value, desired_value, std::memory_order_seq_cst);
+  }
+
+  // Atomically replace the value with desired_value if it matches the expected_value. Doesn't
+  // imply ordering or synchronization constraints.
+  bool CompareAndSetStrongRelaxed(T expected_value, T desired_value) {
+    return this->compare_exchange_strong(expected_value, desired_value, std::memory_order_relaxed);
+  }
+
+  // Atomically replace the value with desired_value if it matches the expected_value. Prior writes
+  // to other memory locations become visible to the threads that do a consume or an acquire on the
+  // same location.
+  bool CompareAndSetStrongRelease(T expected_value, T desired_value) {
+    return this->compare_exchange_strong(expected_value, desired_value, std::memory_order_release);
+  }
+
+  // The same, except it may fail spuriously.
+  bool CompareAndSetWeakRelaxed(T expected_value, T desired_value) {
+    return this->compare_exchange_weak(expected_value, desired_value, std::memory_order_relaxed);
+  }
+
+  // Atomically replace the value with desired_value if it matches the expected_value. Prior writes
+  // made to other memory locations by the thread that did the release become visible in this
+  // thread.
+  bool CompareAndSetWeakAcquire(T expected_value, T desired_value) {
+    return this->compare_exchange_weak(expected_value, desired_value, std::memory_order_acquire);
+  }
+
+  // Atomically replace the value with desired_value if it matches the expected_value. Prior writes
+  // to other memory locations become visible to the threads that do a consume or an acquire on the
+  // same location.
+  bool CompareAndSetWeakRelease(T expected_value, T desired_value) {
+    return this->compare_exchange_weak(expected_value, desired_value, std::memory_order_release);
+  }
+
+  T FetchAndAddSequentiallyConsistent(const T value) {
+    return this->fetch_add(value, std::memory_order_seq_cst);  // Return old_value.
+  }
+
+  T FetchAndAddRelaxed(const T value) {
+    return this->fetch_add(value, std::memory_order_relaxed);  // Return old_value.
+  }
+
+  T FetchAndAddAcquire(const T value) {
+    return this->fetch_add(value, std::memory_order_acquire);  // Return old_value.
+  }
+
+  T FetchAndAddRelease(const T value) {
+    return this->fetch_add(value, std::memory_order_acquire);  // Return old_value.
+  }
+
+  T FetchAndSubSequentiallyConsistent(const T value) {
+    return this->fetch_sub(value, std::memory_order_seq_cst);  // Return old value.
+  }
+
+  T FetchAndSubRelaxed(const T value) {
+    return this->fetch_sub(value, std::memory_order_relaxed);  // Return old value.
+  }
+
+  T FetchAndBitwiseAndSequentiallyConsistent(const T value) {
+    return this->fetch_and(value, std::memory_order_seq_cst);  // Return old_value.
+  }
+
+  T FetchAndBitwiseAndAcquire(const T value) {
+    return this->fetch_and(value, std::memory_order_acquire);  // Return old_value.
+  }
+
+  T FetchAndBitwiseAndRelease(const T value) {
+    return this->fetch_and(value, std::memory_order_release);  // Return old_value.
+  }
+
+  T FetchAndBitwiseOrSequentiallyConsistent(const T value) {
+    return this->fetch_or(value, std::memory_order_seq_cst);  // Return old_value.
+  }
+
+  T FetchAndBitwiseOrAcquire(const T value) {
+    return this->fetch_or(value, std::memory_order_acquire);  // Return old_value.
+  }
+
+  T FetchAndBitwiseOrRelease(const T value) {
+    return this->fetch_or(value, std::memory_order_release);  // Return old_value.
+  }
+
+  T FetchAndBitwiseXorSequentiallyConsistent(const T value) {
+    return this->fetch_xor(value, std::memory_order_seq_cst);  // Return old_value.
+  }
+
+  T FetchAndBitwiseXorAcquire(const T value) {
+    return this->fetch_xor(value, std::memory_order_acquire);  // Return old_value.
+  }
+
+  T FetchAndBitwiseXorRelease(const T value) {
+    return this->fetch_xor(value, std::memory_order_release);  // Return old_value.
+  }
+
+  volatile T* Address() {
+    return reinterpret_cast<T*>(this);
+  }
+
+  static T MaxValue() {
+    return std::numeric_limits<T>::max();
+  }
+};
+
+typedef Atomic<int32_t> AtomicInteger;
+
+static_assert(sizeof(AtomicInteger) == sizeof(int32_t), "Weird AtomicInteger size");
+static_assert(alignof(AtomicInteger) == alignof(int32_t),
+              "AtomicInteger alignment differs from that of underlyingtype");
+static_assert(sizeof(Atomic<int64_t>) == sizeof(int64_t), "Weird Atomic<int64> size");
+
+// Assert the alignment of 64-bit integers is 64-bit. This isn't true on certain 32-bit
+// architectures (e.g. x86-32) but we know that 64-bit integers here are arranged to be 8-byte
+// aligned.
+#if defined(__LP64__)
+  static_assert(alignof(Atomic<int64_t>) == alignof(int64_t),
+                "Atomic<int64> alignment differs from that of underlying type");
+#endif
+
+}  // namespace art
+
+#endif  // ART_LIBARTBASE_BASE_ATOMIC_H_