src/base/atomicops_internals_ppc_gcc.h

// Copyright 2012 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// This file is an internal atomic implementation, use atomicops.h instead.
//

#ifndef V8_BASE_ATOMICOPS_INTERNALS_PPC_H_
#define V8_BASE_ATOMICOPS_INTERNALS_PPC_H_

namespace v8 {
namespace base {

inline Atomic32 NoBarrier_CompareAndSwap(volatile Atomic32* ptr,
                                         Atomic32 old_value,
                                         Atomic32 new_value) {
  return (__sync_val_compare_and_swap(ptr, old_value, new_value));
}

inline Atomic32 NoBarrier_AtomicExchange(volatile Atomic32* ptr,
                                         Atomic32 new_value) {
  Atomic32 old_value;
  do {
    old_value = *ptr;
  } while (__sync_bool_compare_and_swap(ptr, old_value, new_value) == false);
  return old_value;
}

inline Atomic32 NoBarrier_AtomicIncrement(volatile Atomic32* ptr,
                                          Atomic32 increment) {
  return Barrier_AtomicIncrement(ptr, increment);
}

inline Atomic32 Barrier_AtomicIncrement(volatile Atomic32* ptr,
                                        Atomic32 increment) {
  for (;;) {
    Atomic32 old_value = *ptr;
    Atomic32 new_value = old_value + increment;
    if (__sync_bool_compare_and_swap(ptr, old_value, new_value)) {
      return new_value;
      // The exchange took place as expected.
    }
    // Otherwise, *ptr changed mid-loop and we need to retry.
  }
}

inline Atomic32 Acquire_CompareAndSwap(volatile Atomic32* ptr,
                                       Atomic32 old_value, Atomic32 new_value) {
  return NoBarrier_CompareAndSwap(ptr, old_value, new_value);
}

inline Atomic32 Release_CompareAndSwap(volatile Atomic32* ptr,
                                       Atomic32 old_value, Atomic32 new_value) {
  return NoBarrier_CompareAndSwap(ptr, old_value, new_value);
}

inline void NoBarrier_Store(volatile Atomic8* ptr, Atomic8 value) {
  *ptr = value;
}

inline void NoBarrier_Store(volatile Atomic32* ptr, Atomic32 value) {
  *ptr = value;
}

inline void MemoryBarrier() {
  __asm__ __volatile__("sync" : : : "memory"); }

inline void Acquire_Store(volatile Atomic32* ptr, Atomic32 value) {
  *ptr = value;
  MemoryBarrier();
}

inline void Release_Store(volatile Atomic32* ptr, Atomic32 value) {
  MemoryBarrier();
  *ptr = value;
}

inline Atomic8 NoBarrier_Load(volatile const Atomic8* ptr) { return *ptr; }

inline Atomic32 NoBarrier_Load(volatile const Atomic32* ptr) { return *ptr; }

inline Atomic32 Acquire_Load(volatile const Atomic32* ptr) {
  Atomic32 value = *ptr;
  MemoryBarrier();
  return value;
}

inline Atomic32 Release_Load(volatile const Atomic32* ptr) {
  MemoryBarrier();
  return *ptr;
}

#ifdef V8_TARGET_ARCH_PPC64
inline Atomic64 NoBarrier_CompareAndSwap(volatile Atomic64* ptr,
                                         Atomic64 old_value,
                                         Atomic64 new_value) {
  return (__sync_val_compare_and_swap(ptr, old_value, new_value));
}

inline Atomic64 NoBarrier_AtomicExchange(volatile Atomic64* ptr,
                                         Atomic64 new_value) {
  Atomic64 old_value;
  do {
    old_value = *ptr;
  } while (__sync_bool_compare_and_swap(ptr, old_value, new_value) == false);
  return old_value;
}

inline Atomic64 NoBarrier_AtomicIncrement(volatile Atomic64* ptr,
                                          Atomic64 increment) {
  return Barrier_AtomicIncrement(ptr, increment);
}

inline Atomic64 Barrier_AtomicIncrement(volatile Atomic64* ptr,
                                        Atomic64 increment) {
  for (;;) {
    Atomic64 old_value = *ptr;
    Atomic64 new_value = old_value + increment;
    if (__sync_bool_compare_and_swap(ptr, old_value, new_value)) {
      return new_value;
      // The exchange took place as expected.
    }
    // Otherwise, *ptr changed mid-loop and we need to retry.
  }
}

inline Atomic64 Acquire_CompareAndSwap(volatile Atomic64* ptr,
                                       Atomic64 old_value, Atomic64 new_value) {
  return NoBarrier_CompareAndSwap(ptr, old_value, new_value);
}

inline Atomic64 Release_CompareAndSwap(volatile Atomic64* ptr,
                                       Atomic64 old_value, Atomic64 new_value) {
  return NoBarrier_CompareAndSwap(ptr, old_value, new_value);
}

inline void NoBarrier_Store(volatile Atomic64* ptr, Atomic64 value) {
  *ptr = value;
}

inline void Acquire_Store(volatile Atomic64* ptr, Atomic64 value) {
  *ptr = value;
  MemoryBarrier();
}

inline void Release_Store(volatile Atomic64* ptr, Atomic64 value) {
  MemoryBarrier();
  *ptr = value;
}

inline Atomic64 NoBarrier_Load(volatile const Atomic64* ptr) { return *ptr; }

inline Atomic64 Acquire_Load(volatile const Atomic64* ptr) {
  Atomic64 value = *ptr;
  MemoryBarrier();
  return value;
}

inline Atomic64 Release_Load(volatile const Atomic64* ptr) {
  MemoryBarrier();
  return *ptr;
}

#endif
}  // namespace base
}  // namespace v8

#endif  // V8_BASE_ATOMICOPS_INTERNALS_PPC_GCC_H_