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#ifndef GRPC_CORE_LIB_SUPPORT_ATOMIC_WITH_ATM_H
#define GRPC_CORE_LIB_SUPPORT_ATOMIC_WITH_ATM_H

#include <grpc/support/atm.h>

namespace grpc_core {

enum MemoryOrderRelaxed { memory_order_relaxed };

template <class T>
class atomic {
 public:
  static_assert(sizeof(T) <= sizeof(gpr_atm),
                "Atomics of size > sizeof(gpr_atm) are not supported");
  atomic() { gpr_atm_no_barrier_store(&x_, static_cast<gpr_atm>(T())); }

  bool compare_exchange_strong(T& expected, T update, MemoryOrderRelaxed,
                               MemoryOrderRelaxed) {
    if (!gpr_atm_no_barrier_cas(&x_, static_cast<gpr_atm>(expected),
                                static_cast<gpr_atm>(update))) {
      expected = static_cast<T>(gpr_atm_no_barrier_load(&x_));
      return false;
    }
    return true;
  }

 private:
  gpr_atm x_;
};

}  // namespace grpc_core

#endif /* GRPC_CORE_LIB_SUPPORT_ATOMIC_H */