include/grpc/support/atm_gcc_atomic.h

/*
 *
 * Copyright 2015 gRPC authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

#ifndef GRPC_SUPPORT_ATM_GCC_ATOMIC_H
#define GRPC_SUPPORT_ATM_GCC_ATOMIC_H

// IWYU pragma: private, include <grpc/support/atm.h>

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

#ifdef __cplusplus
extern "C" {
#endif

typedef intptr_t gpr_atm;
#define GPR_ATM_MAX INTPTR_MAX
#define GPR_ATM_MIN INTPTR_MIN

#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), (intptr_t)(value), __ATOMIC_RELEASE))
#define gpr_atm_no_barrier_store(p, value) \
  (__atomic_store_n((p), (intptr_t)(value), __ATOMIC_RELAXED))

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

static __inline int gpr_atm_no_barrier_cas(gpr_atm* p, gpr_atm o, gpr_atm n) {
  // Need to be c89 compatible, so we can't use false for the fourth argument.
  // NOLINTNEXTLINE(modernize-use-bool-literals)
  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) {
  // Need to be c89 compatible, so we can't use false for the fourth argument.
  // NOLINTNEXTLINE(modernize-use-bool-literals)
  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) {
  // Need to be c89 compatible, so we can't use false for the fourth argument.
  // NOLINTNEXTLINE(modernize-use-bool-literals)
  return __atomic_compare_exchange_n(p, &o, n, 0, __ATOMIC_RELEASE,
                                     __ATOMIC_RELAXED);
}

static __inline int gpr_atm_full_cas(gpr_atm* p, gpr_atm o, gpr_atm n) {
  // Need to be c89 compatible, so we can't use false for the fourth argument.
  // NOLINTNEXTLINE(modernize-use-bool-literals)
  return __atomic_compare_exchange_n(p, &o, n, 0, __ATOMIC_ACQ_REL,
                                     __ATOMIC_RELAXED);
}

#define gpr_atm_full_xchg(p, n) __atomic_exchange_n((p), (n), __ATOMIC_ACQ_REL)

#ifdef __cplusplus
}
#endif

#endif /* GRPC_SUPPORT_ATM_GCC_ATOMIC_H */