sanitizer_atomic.h

//===-- sanitizer_atomic.h --------------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file is a part of ThreadSanitizer/AddressSanitizer runtime.
//
//===----------------------------------------------------------------------===//

#ifndef SANITIZER_ATOMIC_H
#define SANITIZER_ATOMIC_H

#include "sanitizer_internal_defs.h"

namespace __sanitizer {

enum memory_order {
// If the __atomic atomic builtins are supported (Clang/GCC), use the
// compiler provided macro values so that we can map the atomic operations
// to __atomic_* directly.
#ifdef __ATOMIC_SEQ_CST
  memory_order_relaxed = __ATOMIC_RELAXED,
  memory_order_consume = __ATOMIC_CONSUME,
  memory_order_acquire = __ATOMIC_ACQUIRE,
  memory_order_release = __ATOMIC_RELEASE,
  memory_order_acq_rel = __ATOMIC_ACQ_REL,
  memory_order_seq_cst = __ATOMIC_SEQ_CST
#else
  memory_order_relaxed = 1 << 0,
  memory_order_consume = 1 << 1,
  memory_order_acquire = 1 << 2,
  memory_order_release = 1 << 3,
  memory_order_acq_rel = 1 << 4,
  memory_order_seq_cst = 1 << 5
#endif
};

struct atomic_uint8_t {
  typedef u8 Type;
  volatile Type val_dont_use;
};

struct atomic_uint16_t {
  typedef u16 Type;
  volatile Type val_dont_use;
};

struct atomic_sint32_t {
  typedef s32 Type;
  volatile Type val_dont_use;
};

struct atomic_uint32_t {
  typedef u32 Type;
  volatile Type val_dont_use;
};

struct atomic_uint64_t {
  typedef u64 Type;
  // On 32-bit platforms u64 is not necessary aligned on 8 bytes.
  alignas(8) volatile Type val_dont_use;
};

struct atomic_uintptr_t {
  typedef uptr Type;
  volatile Type val_dont_use;
};

}  // namespace __sanitizer

#if defined(__clang__) || defined(__GNUC__)
# include "sanitizer_atomic_clang.h"
#elif defined(_MSC_VER)
# include "sanitizer_atomic_msvc.h"
#else
# error "Unsupported compiler"
#endif

namespace __sanitizer {

// Clutter-reducing helpers.

template<typename T>
inline typename T::Type atomic_load_relaxed(const volatile T *a) {
  return atomic_load(a, memory_order_relaxed);
}

template<typename T>
inline void atomic_store_relaxed(volatile T *a, typename T::Type v) {
  atomic_store(a, v, memory_order_relaxed);
}

}  // namespace __sanitizer

#endif  // SANITIZER_ATOMIC_H