atm_gcc_atomic.h

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 *
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#ifndef GRPC_SUPPORT_ATM_GCC_ATOMIC_H
#define GRPC_SUPPORT_ATM_GCC_ATOMIC_H

/* atm_platform.h for gcc and gcc-like compilers with the
   __atomic_* interface.  */
#include <grpc/support/port_platform.h>

typedef gpr_intptr gpr_atm;

#define gpr_atm_full_barrier() (__atomic_thread_fence(__ATOMIC_SEQ_CST))

#define gpr_atm_acq_load(p) (__atomic_load_n((p), __ATOMIC_ACQUIRE))
#define gpr_atm_no_barrier_load(p) (__atomic_load_n((p), __ATOMIC_RELAXED))
#define gpr_atm_rel_store(p, value) \
  (__atomic_store_n((p), (gpr_intptr)(value), __ATOMIC_RELEASE))

#define gpr_atm_no_barrier_fetch_add(p, delta) \
  (__atomic_fetch_add((p), (gpr_intptr)(delta), __ATOMIC_RELAXED))
#define gpr_atm_full_fetch_add(p, delta) \
  (__atomic_fetch_add((p), (gpr_intptr)(delta), __ATOMIC_ACQ_REL))

static __inline int gpr_atm_no_barrier_cas(gpr_atm *p, gpr_atm o, gpr_atm n) {
  return __atomic_compare_exchange_n(p, &o, n, 0, __ATOMIC_RELAXED,
                                     __ATOMIC_RELAXED);
}

static __inline int gpr_atm_acq_cas(gpr_atm *p, gpr_atm o, gpr_atm n) {
  return __atomic_compare_exchange_n(p, &o, n, 0, __ATOMIC_ACQUIRE,
                                     __ATOMIC_RELAXED);
}

static __inline int gpr_atm_rel_cas(gpr_atm *p, gpr_atm o, gpr_atm n) {
  return __atomic_compare_exchange_n(p, &o, n, 0, __ATOMIC_RELEASE,
                                     __ATOMIC_RELAXED);
}

#endif  /* GRPC_SUPPORT_ATM_GCC_ATOMIC_H */