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//                        Kokkos v. 2.0
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#ifndef KOKKOS_KOKKOS_ATOMIC_MEMORY_ORDER_HPP
#define KOKKOS_KOKKOS_ATOMIC_MEMORY_ORDER_HPP

#include <Kokkos_Macros.hpp>

#include <atomic>

namespace Kokkos {
namespace Impl {

/** @file
 * Provides strongly-typed analogs of the standard memory order enumerators.
 * In addition to (very slightly) reducing the constant propagation burden on
 * the compiler, this allows us to give compile-time errors for things that
 * don't make sense, like atomic_load with memory order release.
 */

struct memory_order_seq_cst_t {
  using memory_order = memory_order_seq_cst_t;
#if defined(KOKKOS_ENABLE_GNU_ATOMICS) \
    || defined(KOKKOS_ENABLE_INTEL_ATOMICS) \
    || defined(KOKKOS_ENABLE_CUDA_ASM_ATOMICS)
  static constexpr auto gnu_constant = __ATOMIC_SEQ_CST;
#endif
  static constexpr auto std_constant = std::memory_order_seq_cst;
};
constexpr memory_order_seq_cst_t memory_order_seq_cst = { };

struct memory_order_relaxed_t {
  using memory_order = memory_order_relaxed_t;
#if defined(KOKKOS_ENABLE_GNU_ATOMICS) \
    || defined(KOKKOS_ENABLE_INTEL_ATOMICS) \
    || defined(KOKKOS_ENABLE_CUDA_ASM_ATOMICS)
  static constexpr auto gnu_constant = __ATOMIC_RELAXED;
#endif
  static constexpr auto std_constant = std::memory_order_relaxed;
};
constexpr memory_order_relaxed_t memory_order_relaxed = { };

struct memory_order_acquire_t {
  using memory_order = memory_order_acquire_t;
#if defined(KOKKOS_ENABLE_GNU_ATOMICS) \
    || defined(KOKKOS_ENABLE_INTEL_ATOMICS) \
    || defined(KOKKOS_ENABLE_CUDA_ASM_ATOMICS)
  static constexpr auto gnu_constant = __ATOMIC_ACQUIRE;
#endif
  static constexpr auto std_constant = std::memory_order_acquire;
};
constexpr memory_order_acquire_t memory_order_acquire = { };

struct memory_order_release_t {
  using memory_order = memory_order_release_t;
#if defined(KOKKOS_ENABLE_GNU_ATOMICS) \
    || defined(KOKKOS_ENABLE_INTEL_ATOMICS) \
    || defined(KOKKOS_ENABLE_CUDA_ASM_ATOMICS)
  static constexpr auto gnu_constant = __ATOMIC_RELEASE;
#endif
  static constexpr auto std_constant = std::memory_order_release;
};
constexpr memory_order_release_t memory_order_release = { };

struct memory_order_acq_rel_t {
  using memory_order = memory_order_acq_rel_t;
#if defined(KOKKOS_ENABLE_GNU_ATOMICS) \
    || defined(KOKKOS_ENABLE_INTEL_ATOMICS) \
    || defined(KOKKOS_ENABLE_CUDA_ASM_ATOMICS)
  static constexpr auto gnu_constant = __ATOMIC_ACQ_REL;
#endif
  static constexpr auto std_constant = std::memory_order_acq_rel;
};
constexpr memory_order_acq_rel_t memory_order_acq_rel = { };


// Intentionally omit consume (for now)

} // end namespace Impl
} // end namespace Kokkos

#endif //KOKKOS_KOKKOS_ATOMIC_MEMORY_ORDER_HPP
