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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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#include "precompiled.hpp"
#include "runtime/atomic.hpp"
#include "unittest.hpp"

// These tests of Atomic only verify functionality.  They don't verify atomicity.

template<typename T>
struct AtomicEnumTestSupport {
  volatile T _test_value;

  AtomicEnumTestSupport() : _test_value{} {}

  void test_store_load(T value) {
    EXPECT_NE(value, Atomic::load(&_test_value));
    Atomic::store(&_test_value, value);
    EXPECT_EQ(value, Atomic::load(&_test_value));
  }

  void test_cmpxchg(T value1, T value2) {
    EXPECT_NE(value1, Atomic::load(&_test_value));
    Atomic::store(&_test_value, value1);
    EXPECT_EQ(value1, Atomic::cmpxchg(&_test_value, value2, value2));
    EXPECT_EQ(value1, Atomic::load(&_test_value));
    EXPECT_EQ(value1, Atomic::cmpxchg(&_test_value, value1, value2));
    EXPECT_EQ(value2, Atomic::load(&_test_value));
  }

  void test_xchg(T value1, T value2) {
    EXPECT_NE(value1, Atomic::load(&_test_value));
    Atomic::store(&_test_value, value1);
    EXPECT_EQ(value1, Atomic::xchg(&_test_value, value2));
    EXPECT_EQ(value2, Atomic::load(&_test_value));
  }
};

namespace AtomicEnumTestUnscoped {       // Scope the enumerators.
  enum TestEnum { A, B, C };
}

TEST(AtomicEnumTest, unscoped_enum) {
  using namespace AtomicEnumTestUnscoped;
  using Support = AtomicEnumTestSupport<TestEnum>;

  Support().test_store_load(B);
  Support().test_cmpxchg(B, C);
  Support().test_xchg(B, C);
}

enum class AtomicEnumTestScoped { A, B, C };

TEST(AtomicEnumTest, scoped_enum) {
  const AtomicEnumTestScoped B = AtomicEnumTestScoped::B;
  const AtomicEnumTestScoped C = AtomicEnumTestScoped::C;
  using Support = AtomicEnumTestSupport<AtomicEnumTestScoped>;

  Support().test_store_load(B);
  Support().test_cmpxchg(B, C);
  Support().test_xchg(B, C);
}