atomic_base.h
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// -*- C++ -*- header.
// Copyright (C) 2008-2013 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
/** @file bits/atomic_base.h
* This is an internal header file, included by other library headers.
* Do not attempt to use it directly. @headername{atomic}
*/
#ifndef _GLIBCXX_ATOMIC_BASE_H
#define _GLIBCXX_ATOMIC_BASE_H 1
#pragma GCC system_header
#include <bits/c++config.h>
#include <stdbool.h>
#include <stdint.h>
#include <bits/atomic_lockfree_defines.h>
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
/**
* @defgroup atomics Atomics
*
* Components for performing atomic operations.
* @{
*/
/// Enumeration for memory_order
typedef enum memory_order
{
memory_order_relaxed,
memory_order_consume,
memory_order_acquire,
memory_order_release,
memory_order_acq_rel,
memory_order_seq_cst
} memory_order;
enum __memory_order_modifier
{
__memory_order_mask = 0x0ffff,
__memory_order_modifier_mask = 0xffff0000,
__memory_order_hle_acquire = 0x10000,
__memory_order_hle_release = 0x20000
};
constexpr memory_order
operator|(memory_order __m, __memory_order_modifier __mod)
{
return memory_order(__m | int(__mod));
}
constexpr memory_order
operator&(memory_order __m, __memory_order_modifier __mod)
{
return memory_order(__m & int(__mod));
}
// Drop release ordering as per [atomics.types.operations.req]/21
constexpr memory_order
__cmpexch_failure_order2(memory_order __m) noexcept
{
return __m == memory_order_acq_rel ? memory_order_acquire
: __m == memory_order_release ? memory_order_relaxed : __m;
}
constexpr memory_order
__cmpexch_failure_order(memory_order __m) noexcept
{
return memory_order(__cmpexch_failure_order2(__m & __memory_order_mask)
| (__m & __memory_order_modifier_mask));
}
inline void
atomic_thread_fence(memory_order __m) noexcept
{ __atomic_thread_fence(__m); }
inline void
atomic_signal_fence(memory_order __m) noexcept
{ __atomic_signal_fence(__m); }
/// kill_dependency
template<typename _Tp>
inline _Tp
kill_dependency(_Tp __y) noexcept
{
_Tp __ret(__y);
return __ret;
}
// Base types for atomics.
template<typename _IntTp>
struct __atomic_base;
/// atomic_char
typedef __atomic_base<char> atomic_char;
/// atomic_schar
typedef __atomic_base<signed char> atomic_schar;
/// atomic_uchar
typedef __atomic_base<unsigned char> atomic_uchar;
/// atomic_short
typedef __atomic_base<short> atomic_short;
/// atomic_ushort
typedef __atomic_base<unsigned short> atomic_ushort;
/// atomic_int
typedef __atomic_base<int> atomic_int;
/// atomic_uint
typedef __atomic_base<unsigned int> atomic_uint;
/// atomic_long
typedef __atomic_base<long> atomic_long;
/// atomic_ulong
typedef __atomic_base<unsigned long> atomic_ulong;
/// atomic_llong
typedef __atomic_base<long long> atomic_llong;
/// atomic_ullong
typedef __atomic_base<unsigned long long> atomic_ullong;
/// atomic_wchar_t
typedef __atomic_base<wchar_t> atomic_wchar_t;
/// atomic_char16_t
typedef __atomic_base<char16_t> atomic_char16_t;
/// atomic_char32_t
typedef __atomic_base<char32_t> atomic_char32_t;
/// atomic_char32_t
typedef __atomic_base<char32_t> atomic_char32_t;
/// atomic_int_least8_t
typedef __atomic_base<int_least8_t> atomic_int_least8_t;
/// atomic_uint_least8_t
typedef __atomic_base<uint_least8_t> atomic_uint_least8_t;
/// atomic_int_least16_t
typedef __atomic_base<int_least16_t> atomic_int_least16_t;
/// atomic_uint_least16_t
typedef __atomic_base<uint_least16_t> atomic_uint_least16_t;
/// atomic_int_least32_t
typedef __atomic_base<int_least32_t> atomic_int_least32_t;
/// atomic_uint_least32_t
typedef __atomic_base<uint_least32_t> atomic_uint_least32_t;
/// atomic_int_least64_t
typedef __atomic_base<int_least64_t> atomic_int_least64_t;
/// atomic_uint_least64_t
typedef __atomic_base<uint_least64_t> atomic_uint_least64_t;
/// atomic_int_fast8_t
typedef __atomic_base<int_fast8_t> atomic_int_fast8_t;
/// atomic_uint_fast8_t
typedef __atomic_base<uint_fast8_t> atomic_uint_fast8_t;
/// atomic_int_fast16_t
typedef __atomic_base<int_fast16_t> atomic_int_fast16_t;
/// atomic_uint_fast16_t
typedef __atomic_base<uint_fast16_t> atomic_uint_fast16_t;
/// atomic_int_fast32_t
typedef __atomic_base<int_fast32_t> atomic_int_fast32_t;
/// atomic_uint_fast32_t
typedef __atomic_base<uint_fast32_t> atomic_uint_fast32_t;
/// atomic_int_fast64_t
typedef __atomic_base<int_fast64_t> atomic_int_fast64_t;
/// atomic_uint_fast64_t
typedef __atomic_base<uint_fast64_t> atomic_uint_fast64_t;
/// atomic_intptr_t
typedef __atomic_base<intptr_t> atomic_intptr_t;
/// atomic_uintptr_t
typedef __atomic_base<uintptr_t> atomic_uintptr_t;
/// atomic_size_t
typedef __atomic_base<size_t> atomic_size_t;
/// atomic_intmax_t
typedef __atomic_base<intmax_t> atomic_intmax_t;
/// atomic_uintmax_t
typedef __atomic_base<uintmax_t> atomic_uintmax_t;
/// atomic_ptrdiff_t
typedef __atomic_base<ptrdiff_t> atomic_ptrdiff_t;
#define ATOMIC_VAR_INIT(_VI) { _VI }
template<typename _Tp>
struct atomic;
template<typename _Tp>
struct atomic<_Tp*>;
/**
* @brief Base type for atomic_flag.
*
* Base type is POD with data, allowing atomic_flag to derive from
* it and meet the standard layout type requirement. In addition to
* compatibilty with a C interface, this allows different
* implementations of atomic_flag to use the same atomic operation
* functions, via a standard conversion to the __atomic_flag_base
* argument.
*/
_GLIBCXX_BEGIN_EXTERN_C
struct __atomic_flag_base
{
/* The target's "set" value for test-and-set may not be exactly 1. */
#if __GCC_ATOMIC_TEST_AND_SET_TRUEVAL == 1
bool _M_i;
#else
unsigned char _M_i;
#endif
};
_GLIBCXX_END_EXTERN_C
#define ATOMIC_FLAG_INIT { 0 }
/// atomic_flag
struct atomic_flag : public __atomic_flag_base
{
atomic_flag() noexcept = default;
~atomic_flag() noexcept = default;
atomic_flag(const atomic_flag&) = delete;
atomic_flag& operator=(const atomic_flag&) = delete;
atomic_flag& operator=(const atomic_flag&) volatile = delete;
// Conversion to ATOMIC_FLAG_INIT.
constexpr atomic_flag(bool __i) noexcept
: __atomic_flag_base({ __i ? __GCC_ATOMIC_TEST_AND_SET_TRUEVAL : 0 })
{ }
bool
test_and_set(memory_order __m = memory_order_seq_cst) noexcept
{
return __atomic_test_and_set (&_M_i, __m);
}
bool
test_and_set(memory_order __m = memory_order_seq_cst) volatile noexcept
{
return __atomic_test_and_set (&_M_i, __m);
}
void
clear(memory_order __m = memory_order_seq_cst) noexcept
{
memory_order __b = __m & __memory_order_mask;
__glibcxx_assert(__b != memory_order_consume);
__glibcxx_assert(__b != memory_order_acquire);
__glibcxx_assert(__b != memory_order_acq_rel);
__atomic_clear (&_M_i, __m);
}
void
clear(memory_order __m = memory_order_seq_cst) volatile noexcept
{
memory_order __b = __m & __memory_order_mask;
__glibcxx_assert(__b != memory_order_consume);
__glibcxx_assert(__b != memory_order_acquire);
__glibcxx_assert(__b != memory_order_acq_rel);
__atomic_clear (&_M_i, __m);
}
};
/// Base class for atomic integrals.
//
// For each of the integral types, define atomic_[integral type] struct
//
// atomic_bool bool
// atomic_char char
// atomic_schar signed char
// atomic_uchar unsigned char
// atomic_short short
// atomic_ushort unsigned short
// atomic_int int
// atomic_uint unsigned int
// atomic_long long
// atomic_ulong unsigned long
// atomic_llong long long
// atomic_ullong unsigned long long
// atomic_char16_t char16_t
// atomic_char32_t char32_t
// atomic_wchar_t wchar_t
//
// NB: Assuming _ITp is an integral scalar type that is 1, 2, 4, or
// 8 bytes, since that is what GCC built-in functions for atomic
// memory access expect.
template<typename _ITp>
struct __atomic_base
{
private:
typedef _ITp __int_type;
__int_type _M_i;
public:
__atomic_base() noexcept = default;
~__atomic_base() noexcept = default;
__atomic_base(const __atomic_base&) = delete;
__atomic_base& operator=(const __atomic_base&) = delete;
__atomic_base& operator=(const __atomic_base&) volatile = delete;
// Requires __int_type convertible to _M_i.
constexpr __atomic_base(__int_type __i) noexcept : _M_i (__i) { }
operator __int_type() const noexcept
{ return load(); }
operator __int_type() const volatile noexcept
{ return load(); }
__int_type
operator=(__int_type __i) noexcept
{
store(__i);
return __i;
}
__int_type
operator=(__int_type __i) volatile noexcept
{
store(__i);
return __i;
}
__int_type
operator++(int) noexcept
{ return fetch_add(1); }
__int_type
operator++(int) volatile noexcept
{ return fetch_add(1); }
__int_type
operator--(int) noexcept
{ return fetch_sub(1); }
__int_type
operator--(int) volatile noexcept
{ return fetch_sub(1); }
__int_type
operator++() noexcept
{ return __atomic_add_fetch(&_M_i, 1, memory_order_seq_cst); }
__int_type
operator++() volatile noexcept
{ return __atomic_add_fetch(&_M_i, 1, memory_order_seq_cst); }
__int_type
operator--() noexcept
{ return __atomic_sub_fetch(&_M_i, 1, memory_order_seq_cst); }
__int_type
operator--() volatile noexcept
{ return __atomic_sub_fetch(&_M_i, 1, memory_order_seq_cst); }
__int_type
operator+=(__int_type __i) noexcept
{ return __atomic_add_fetch(&_M_i, __i, memory_order_seq_cst); }
__int_type
operator+=(__int_type __i) volatile noexcept
{ return __atomic_add_fetch(&_M_i, __i, memory_order_seq_cst); }
__int_type
operator-=(__int_type __i) noexcept
{ return __atomic_sub_fetch(&_M_i, __i, memory_order_seq_cst); }
__int_type
operator-=(__int_type __i) volatile noexcept
{ return __atomic_sub_fetch(&_M_i, __i, memory_order_seq_cst); }
__int_type
operator&=(__int_type __i) noexcept
{ return __atomic_and_fetch(&_M_i, __i, memory_order_seq_cst); }
__int_type
operator&=(__int_type __i) volatile noexcept
{ return __atomic_and_fetch(&_M_i, __i, memory_order_seq_cst); }
__int_type
operator|=(__int_type __i) noexcept
{ return __atomic_or_fetch(&_M_i, __i, memory_order_seq_cst); }
__int_type
operator|=(__int_type __i) volatile noexcept
{ return __atomic_or_fetch(&_M_i, __i, memory_order_seq_cst); }
__int_type
operator^=(__int_type __i) noexcept
{ return __atomic_xor_fetch(&_M_i, __i, memory_order_seq_cst); }
__int_type
operator^=(__int_type __i) volatile noexcept
{ return __atomic_xor_fetch(&_M_i, __i, memory_order_seq_cst); }
bool
is_lock_free() const noexcept
{ return __atomic_is_lock_free(sizeof(_M_i), nullptr); }
bool
is_lock_free() const volatile noexcept
{ return __atomic_is_lock_free(sizeof(_M_i), nullptr); }
void
store(__int_type __i, memory_order __m = memory_order_seq_cst) noexcept
{
memory_order __b = __m & __memory_order_mask;
__glibcxx_assert(__b != memory_order_acquire);
__glibcxx_assert(__b != memory_order_acq_rel);
__glibcxx_assert(__b != memory_order_consume);
__atomic_store_n(&_M_i, __i, __m);
}
void
store(__int_type __i,
memory_order __m = memory_order_seq_cst) volatile noexcept
{
memory_order __b = __m & __memory_order_mask;
__glibcxx_assert(__b != memory_order_acquire);
__glibcxx_assert(__b != memory_order_acq_rel);
__glibcxx_assert(__b != memory_order_consume);
__atomic_store_n(&_M_i, __i, __m);
}
__int_type
load(memory_order __m = memory_order_seq_cst) const noexcept
{
memory_order __b = __m & __memory_order_mask;
__glibcxx_assert(__b != memory_order_release);
__glibcxx_assert(__b != memory_order_acq_rel);
return __atomic_load_n(&_M_i, __m);
}
__int_type
load(memory_order __m = memory_order_seq_cst) const volatile noexcept
{
memory_order __b = __m & __memory_order_mask;
__glibcxx_assert(__b != memory_order_release);
__glibcxx_assert(__b != memory_order_acq_rel);
return __atomic_load_n(&_M_i, __m);
}
__int_type
exchange(__int_type __i,
memory_order __m = memory_order_seq_cst) noexcept
{
return __atomic_exchange_n(&_M_i, __i, __m);
}
__int_type
exchange(__int_type __i,
memory_order __m = memory_order_seq_cst) volatile noexcept
{
return __atomic_exchange_n(&_M_i, __i, __m);
}
bool
compare_exchange_weak(__int_type& __i1, __int_type __i2,
memory_order __m1, memory_order __m2) noexcept
{
memory_order __b2 = __m2 & __memory_order_mask;
memory_order __b1 = __m1 & __memory_order_mask;
__glibcxx_assert(__b2 != memory_order_release);
__glibcxx_assert(__b2 != memory_order_acq_rel);
__glibcxx_assert(__b2 <= __b1);
return __atomic_compare_exchange_n(&_M_i, &__i1, __i2, 1, __m1, __m2);
}
bool
compare_exchange_weak(__int_type& __i1, __int_type __i2,
memory_order __m1,
memory_order __m2) volatile noexcept
{
memory_order __b2 = __m2 & __memory_order_mask;
memory_order __b1 = __m1 & __memory_order_mask;
__glibcxx_assert(__b2 != memory_order_release);
__glibcxx_assert(__b2 != memory_order_acq_rel);
__glibcxx_assert(__b2 <= __b1);
return __atomic_compare_exchange_n(&_M_i, &__i1, __i2, 1, __m1, __m2);
}
bool
compare_exchange_weak(__int_type& __i1, __int_type __i2,
memory_order __m = memory_order_seq_cst) noexcept
{
return compare_exchange_weak(__i1, __i2, __m,
__cmpexch_failure_order(__m));
}
bool
compare_exchange_weak(__int_type& __i1, __int_type __i2,
memory_order __m = memory_order_seq_cst) volatile noexcept
{
return compare_exchange_weak(__i1, __i2, __m,
__cmpexch_failure_order(__m));
}
bool
compare_exchange_strong(__int_type& __i1, __int_type __i2,
memory_order __m1, memory_order __m2) noexcept
{
memory_order __b2 = __m2 & __memory_order_mask;
memory_order __b1 = __m1 & __memory_order_mask;
__glibcxx_assert(__b2 != memory_order_release);
__glibcxx_assert(__b2 != memory_order_acq_rel);
__glibcxx_assert(__b2 <= __b1);
return __atomic_compare_exchange_n(&_M_i, &__i1, __i2, 0, __m1, __m2);
}
bool
compare_exchange_strong(__int_type& __i1, __int_type __i2,
memory_order __m1,
memory_order __m2) volatile noexcept
{
memory_order __b2 = __m2 & __memory_order_mask;
memory_order __b1 = __m1 & __memory_order_mask;
__glibcxx_assert(__b2 != memory_order_release);
__glibcxx_assert(__b2 != memory_order_acq_rel);
__glibcxx_assert(__b2 <= __b1);
return __atomic_compare_exchange_n(&_M_i, &__i1, __i2, 0, __m1, __m2);
}
bool
compare_exchange_strong(__int_type& __i1, __int_type __i2,
memory_order __m = memory_order_seq_cst) noexcept
{
return compare_exchange_strong(__i1, __i2, __m,
__cmpexch_failure_order(__m));
}
bool
compare_exchange_strong(__int_type& __i1, __int_type __i2,
memory_order __m = memory_order_seq_cst) volatile noexcept
{
return compare_exchange_strong(__i1, __i2, __m,
__cmpexch_failure_order(__m));
}
__int_type
fetch_add(__int_type __i,
memory_order __m = memory_order_seq_cst) noexcept
{ return __atomic_fetch_add(&_M_i, __i, __m); }
__int_type
fetch_add(__int_type __i,
memory_order __m = memory_order_seq_cst) volatile noexcept
{ return __atomic_fetch_add(&_M_i, __i, __m); }
__int_type
fetch_sub(__int_type __i,
memory_order __m = memory_order_seq_cst) noexcept
{ return __atomic_fetch_sub(&_M_i, __i, __m); }
__int_type
fetch_sub(__int_type __i,
memory_order __m = memory_order_seq_cst) volatile noexcept
{ return __atomic_fetch_sub(&_M_i, __i, __m); }
__int_type
fetch_and(__int_type __i,
memory_order __m = memory_order_seq_cst) noexcept
{ return __atomic_fetch_and(&_M_i, __i, __m); }
__int_type
fetch_and(__int_type __i,
memory_order __m = memory_order_seq_cst) volatile noexcept
{ return __atomic_fetch_and(&_M_i, __i, __m); }
__int_type
fetch_or(__int_type __i,
memory_order __m = memory_order_seq_cst) noexcept
{ return __atomic_fetch_or(&_M_i, __i, __m); }
__int_type
fetch_or(__int_type __i,
memory_order __m = memory_order_seq_cst) volatile noexcept
{ return __atomic_fetch_or(&_M_i, __i, __m); }
__int_type
fetch_xor(__int_type __i,
memory_order __m = memory_order_seq_cst) noexcept
{ return __atomic_fetch_xor(&_M_i, __i, __m); }
__int_type
fetch_xor(__int_type __i,
memory_order __m = memory_order_seq_cst) volatile noexcept
{ return __atomic_fetch_xor(&_M_i, __i, __m); }
};
/// Partial specialization for pointer types.
template<typename _PTp>
struct __atomic_base<_PTp*>
{
private:
typedef _PTp* __pointer_type;
__pointer_type _M_p;
// Factored out to facilitate explicit specialization.
constexpr ptrdiff_t
_M_type_size(ptrdiff_t __d) { return __d * sizeof(_PTp); }
constexpr ptrdiff_t
_M_type_size(ptrdiff_t __d) volatile { return __d * sizeof(_PTp); }
public:
__atomic_base() noexcept = default;
~__atomic_base() noexcept = default;
__atomic_base(const __atomic_base&) = delete;
__atomic_base& operator=(const __atomic_base&) = delete;
__atomic_base& operator=(const __atomic_base&) volatile = delete;
// Requires __pointer_type convertible to _M_p.
constexpr __atomic_base(__pointer_type __p) noexcept : _M_p (__p) { }
operator __pointer_type() const noexcept
{ return load(); }
operator __pointer_type() const volatile noexcept
{ return load(); }
__pointer_type
operator=(__pointer_type __p) noexcept
{
store(__p);
return __p;
}
__pointer_type
operator=(__pointer_type __p) volatile noexcept
{
store(__p);
return __p;
}
__pointer_type
operator++(int) noexcept
{ return fetch_add(1); }
__pointer_type
operator++(int) volatile noexcept
{ return fetch_add(1); }
__pointer_type
operator--(int) noexcept
{ return fetch_sub(1); }
__pointer_type
operator--(int) volatile noexcept
{ return fetch_sub(1); }
__pointer_type
operator++() noexcept
{ return __atomic_add_fetch(&_M_p, _M_type_size(1),
memory_order_seq_cst); }
__pointer_type
operator++() volatile noexcept
{ return __atomic_add_fetch(&_M_p, _M_type_size(1),
memory_order_seq_cst); }
__pointer_type
operator--() noexcept
{ return __atomic_sub_fetch(&_M_p, _M_type_size(1),
memory_order_seq_cst); }
__pointer_type
operator--() volatile noexcept
{ return __atomic_sub_fetch(&_M_p, _M_type_size(1),
memory_order_seq_cst); }
__pointer_type
operator+=(ptrdiff_t __d) noexcept
{ return __atomic_add_fetch(&_M_p, _M_type_size(__d),
memory_order_seq_cst); }
__pointer_type
operator+=(ptrdiff_t __d) volatile noexcept
{ return __atomic_add_fetch(&_M_p, _M_type_size(__d),
memory_order_seq_cst); }
__pointer_type
operator-=(ptrdiff_t __d) noexcept
{ return __atomic_sub_fetch(&_M_p, _M_type_size(__d),
memory_order_seq_cst); }
__pointer_type
operator-=(ptrdiff_t __d) volatile noexcept
{ return __atomic_sub_fetch(&_M_p, _M_type_size(__d),
memory_order_seq_cst); }
bool
is_lock_free() const noexcept
{ return __atomic_is_lock_free(_M_type_size(1), nullptr); }
bool
is_lock_free() const volatile noexcept
{ return __atomic_is_lock_free(_M_type_size(1), nullptr); }
void
store(__pointer_type __p,
memory_order __m = memory_order_seq_cst) noexcept
{
memory_order __b = __m & __memory_order_mask;
__glibcxx_assert(__b != memory_order_acquire);
__glibcxx_assert(__b != memory_order_acq_rel);
__glibcxx_assert(__b != memory_order_consume);
__atomic_store_n(&_M_p, __p, __m);
}
void
store(__pointer_type __p,
memory_order __m = memory_order_seq_cst) volatile noexcept
{
memory_order __b = __m & __memory_order_mask;
__glibcxx_assert(__b != memory_order_acquire);
__glibcxx_assert(__b != memory_order_acq_rel);
__glibcxx_assert(__b != memory_order_consume);
__atomic_store_n(&_M_p, __p, __m);
}
__pointer_type
load(memory_order __m = memory_order_seq_cst) const noexcept
{
memory_order __b = __m & __memory_order_mask;
__glibcxx_assert(__b != memory_order_release);
__glibcxx_assert(__b != memory_order_acq_rel);
return __atomic_load_n(&_M_p, __m);
}
__pointer_type
load(memory_order __m = memory_order_seq_cst) const volatile noexcept
{
memory_order __b = __m & __memory_order_mask;
__glibcxx_assert(__b != memory_order_release);
__glibcxx_assert(__b != memory_order_acq_rel);
return __atomic_load_n(&_M_p, __m);
}
__pointer_type
exchange(__pointer_type __p,
memory_order __m = memory_order_seq_cst) noexcept
{
return __atomic_exchange_n(&_M_p, __p, __m);
}
__pointer_type
exchange(__pointer_type __p,
memory_order __m = memory_order_seq_cst) volatile noexcept
{
return __atomic_exchange_n(&_M_p, __p, __m);
}
bool
compare_exchange_strong(__pointer_type& __p1, __pointer_type __p2,
memory_order __m1,
memory_order __m2) noexcept
{
memory_order __b2 = __m2 & __memory_order_mask;
memory_order __b1 = __m1 & __memory_order_mask;
__glibcxx_assert(__b2 != memory_order_release);
__glibcxx_assert(__b2 != memory_order_acq_rel);
__glibcxx_assert(__b2 <= __b1);
return __atomic_compare_exchange_n(&_M_p, &__p1, __p2, 0, __m1, __m2);
}
bool
compare_exchange_strong(__pointer_type& __p1, __pointer_type __p2,
memory_order __m1,
memory_order __m2) volatile noexcept
{
memory_order __b2 = __m2 & __memory_order_mask;
memory_order __b1 = __m1 & __memory_order_mask;
__glibcxx_assert(__b2 != memory_order_release);
__glibcxx_assert(__b2 != memory_order_acq_rel);
__glibcxx_assert(__b2 <= __b1);
return __atomic_compare_exchange_n(&_M_p, &__p1, __p2, 0, __m1, __m2);
}
__pointer_type
fetch_add(ptrdiff_t __d,
memory_order __m = memory_order_seq_cst) noexcept
{ return __atomic_fetch_add(&_M_p, _M_type_size(__d), __m); }
__pointer_type
fetch_add(ptrdiff_t __d,
memory_order __m = memory_order_seq_cst) volatile noexcept
{ return __atomic_fetch_add(&_M_p, _M_type_size(__d), __m); }
__pointer_type
fetch_sub(ptrdiff_t __d,
memory_order __m = memory_order_seq_cst) noexcept
{ return __atomic_fetch_sub(&_M_p, _M_type_size(__d), __m); }
__pointer_type
fetch_sub(ptrdiff_t __d,
memory_order __m = memory_order_seq_cst) volatile noexcept
{ return __atomic_fetch_sub(&_M_p, _M_type_size(__d), __m); }
};
// @} group atomics
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace std
#endif