grpc/include/grpc/support/atm_gcc_sync.h

/*
 *
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#ifndef __GRPC_SUPPORT_ATM_GCC_SYNC_H__
#define __GRPC_SUPPORT_ATM_GCC_SYNC_H__

/* variant of atm_platform.h for gcc and gcc-like compiers with __sync_*
   interface */
#include <grpc/support/port_platform.h>

typedef gpr_intptr gpr_atm;

#if defined(__i386) || defined(__x86_64__)
/* All loads are acquire loads and all stores are release stores.  */
#define GPR_ATM_LS_BARRIER_() __asm__ __volatile__("" : : : "memory")
#else
#define GPR_ATM_LS_BARRIER_() gpr_atm_full_barrier()
#endif

#define gpr_atm_full_barrier() (__sync_synchronize())

static __inline gpr_atm gpr_atm_acq_load(const gpr_atm *p) {
  gpr_atm value = *p;
  GPR_ATM_LS_BARRIER_();
  return value;
}

static __inline void gpr_atm_rel_store(gpr_atm *p, gpr_atm value) {
  GPR_ATM_LS_BARRIER_();
  *p = value;
}

#undef GPR_ATM_LS_BARRIER_

#define gpr_atm_no_barrier_fetch_add(p, delta) \
  gpr_atm_full_fetch_add((p), (delta))
#define gpr_atm_full_fetch_add(p, delta) (__sync_fetch_and_add((p), (delta)))

#define gpr_atm_no_barrier_cas(p, o, n) gpr_atm_acq_cas((p), (o), (n))
#define gpr_atm_acq_cas(p, o, n) (__sync_bool_compare_and_swap((p), (o), (n)))
#define gpr_atm_rel_cas(p, o, n) gpr_atm_acq_cas((p), (o), (n))

#endif /* __GRPC_SUPPORT_ATM_GCC_SYNC_H__ */