atomic_base.h
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// -*- C++ -*- header.
// Copyright (C) 2008-2021 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 <stdint.h>
#include <bits/atomic_lockfree_defines.h>
#include <bits/move.h>
#if __cplusplus > 201703L && _GLIBCXX_HOSTED
#include <bits/atomic_wait.h>
#endif
#ifndef _GLIBCXX_ALWAYS_INLINE
#define _GLIBCXX_ALWAYS_INLINE inline __attribute__((__always_inline__))
#endif
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
/**
* @defgroup atomics Atomics
*
* Components for performing atomic operations.
* @{
*/
/// Enumeration for memory_order
#if __cplusplus > 201703L
enum class memory_order : int
{
relaxed,
consume,
acquire,
release,
acq_rel,
seq_cst
};
inline constexpr memory_order memory_order_relaxed = memory_order::relaxed;
inline constexpr memory_order memory_order_consume = memory_order::consume;
inline constexpr memory_order memory_order_acquire = memory_order::acquire;
inline constexpr memory_order memory_order_release = memory_order::release;
inline constexpr memory_order memory_order_acq_rel = memory_order::acq_rel;
inline constexpr memory_order memory_order_seq_cst = memory_order::seq_cst;
#else
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;
#endif
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(int(__m) | int(__mod));
}
constexpr memory_order
operator&(memory_order __m, __memory_order_modifier __mod)
{
return memory_order(int(__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)
| __memory_order_modifier(__m & __memory_order_modifier_mask));
}
constexpr bool
__is_valid_cmpexch_failure_order(memory_order __m) noexcept
{
return (__m & __memory_order_mask) != memory_order_release
&& (__m & __memory_order_mask) != memory_order_acq_rel;
}
_GLIBCXX_ALWAYS_INLINE void
atomic_thread_fence(memory_order __m) noexcept
{ __atomic_thread_fence(int(__m)); }
_GLIBCXX_ALWAYS_INLINE void
atomic_signal_fence(memory_order __m) noexcept
{ __atomic_signal_fence(int(__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;
#if __cplusplus <= 201703L
# define _GLIBCXX20_INIT(I)
#else
# define __cpp_lib_atomic_value_initialization 201911L
# define _GLIBCXX20_INIT(I) = I
#endif
#define ATOMIC_VAR_INIT(_VI) { _VI }
template<typename _Tp>
struct atomic;
template<typename _Tp>
struct atomic<_Tp*>;
/* The target's "set" value for test-and-set may not be exactly 1. */
#if __GCC_ATOMIC_TEST_AND_SET_TRUEVAL == 1
typedef bool __atomic_flag_data_type;
#else
typedef unsigned char __atomic_flag_data_type;
#endif
/**
* @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
* compatibility 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
{
__atomic_flag_data_type _M_i _GLIBCXX20_INIT({});
};
_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{ _S_init(__i) }
{ }
_GLIBCXX_ALWAYS_INLINE bool
test_and_set(memory_order __m = memory_order_seq_cst) noexcept
{
return __atomic_test_and_set (&_M_i, int(__m));
}
_GLIBCXX_ALWAYS_INLINE bool
test_and_set(memory_order __m = memory_order_seq_cst) volatile noexcept
{
return __atomic_test_and_set (&_M_i, int(__m));
}
#if __cplusplus > 201703L
#define __cpp_lib_atomic_flag_test 201907L
_GLIBCXX_ALWAYS_INLINE bool
test(memory_order __m = memory_order_seq_cst) const noexcept
{
__atomic_flag_data_type __v;
__atomic_load(&_M_i, &__v, int(__m));
return __v == __GCC_ATOMIC_TEST_AND_SET_TRUEVAL;
}
_GLIBCXX_ALWAYS_INLINE bool
test(memory_order __m = memory_order_seq_cst) const volatile noexcept
{
__atomic_flag_data_type __v;
__atomic_load(&_M_i, &__v, int(__m));
return __v == __GCC_ATOMIC_TEST_AND_SET_TRUEVAL;
}
#if __cpp_lib_atomic_wait
_GLIBCXX_ALWAYS_INLINE void
wait(bool __old,
memory_order __m = memory_order_seq_cst) const noexcept
{
const __atomic_flag_data_type __v
= __old ? __GCC_ATOMIC_TEST_AND_SET_TRUEVAL : 0;
std::__atomic_wait_address_v(&_M_i, __v,
[__m, this] { return __atomic_load_n(&_M_i, int(__m)); });
}
// TODO add const volatile overload
_GLIBCXX_ALWAYS_INLINE void
notify_one() noexcept
{ std::__atomic_notify_address(&_M_i, false); }
// TODO add const volatile overload
_GLIBCXX_ALWAYS_INLINE void
notify_all() noexcept
{ std::__atomic_notify_address(&_M_i, true); }
// TODO add const volatile overload
#endif // __cpp_lib_atomic_wait
#endif // C++20
_GLIBCXX_ALWAYS_INLINE void
clear(memory_order __m = memory_order_seq_cst) noexcept
{
memory_order __b __attribute__ ((__unused__))
= __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, int(__m));
}
_GLIBCXX_ALWAYS_INLINE void
clear(memory_order __m = memory_order_seq_cst) volatile noexcept
{
memory_order __b __attribute__ ((__unused__))
= __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, int(__m));
}
private:
static constexpr __atomic_flag_data_type
_S_init(bool __i)
{ return __i ? __GCC_ATOMIC_TEST_AND_SET_TRUEVAL : 0; }
};
/// 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_char8_t char8_t
// 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
{
using value_type = _ITp;
using difference_type = value_type;
private:
typedef _ITp __int_type;
static constexpr int _S_alignment =
sizeof(_ITp) > alignof(_ITp) ? sizeof(_ITp) : alignof(_ITp);
alignas(_S_alignment) __int_type _M_i _GLIBCXX20_INIT(0);
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, int(memory_order_seq_cst)); }
__int_type
operator++() volatile noexcept
{ return __atomic_add_fetch(&_M_i, 1, int(memory_order_seq_cst)); }
__int_type
operator--() noexcept
{ return __atomic_sub_fetch(&_M_i, 1, int(memory_order_seq_cst)); }
__int_type
operator--() volatile noexcept
{ return __atomic_sub_fetch(&_M_i, 1, int(memory_order_seq_cst)); }
__int_type
operator+=(__int_type __i) noexcept
{ return __atomic_add_fetch(&_M_i, __i, int(memory_order_seq_cst)); }
__int_type
operator+=(__int_type __i) volatile noexcept
{ return __atomic_add_fetch(&_M_i, __i, int(memory_order_seq_cst)); }
__int_type
operator-=(__int_type __i) noexcept
{ return __atomic_sub_fetch(&_M_i, __i, int(memory_order_seq_cst)); }
__int_type
operator-=(__int_type __i) volatile noexcept
{ return __atomic_sub_fetch(&_M_i, __i, int(memory_order_seq_cst)); }
__int_type
operator&=(__int_type __i) noexcept
{ return __atomic_and_fetch(&_M_i, __i, int(memory_order_seq_cst)); }
__int_type
operator&=(__int_type __i) volatile noexcept
{ return __atomic_and_fetch(&_M_i, __i, int(memory_order_seq_cst)); }
__int_type
operator|=(__int_type __i) noexcept
{ return __atomic_or_fetch(&_M_i, __i, int(memory_order_seq_cst)); }
__int_type
operator|=(__int_type __i) volatile noexcept
{ return __atomic_or_fetch(&_M_i, __i, int(memory_order_seq_cst)); }
__int_type
operator^=(__int_type __i) noexcept
{ return __atomic_xor_fetch(&_M_i, __i, int(memory_order_seq_cst)); }
__int_type
operator^=(__int_type __i) volatile noexcept
{ return __atomic_xor_fetch(&_M_i, __i, int(memory_order_seq_cst)); }
bool
is_lock_free() const noexcept
{
// Use a fake, minimally aligned pointer.
return __atomic_is_lock_free(sizeof(_M_i),
reinterpret_cast<void *>(-_S_alignment));
}
bool
is_lock_free() const volatile noexcept
{
// Use a fake, minimally aligned pointer.
return __atomic_is_lock_free(sizeof(_M_i),
reinterpret_cast<void *>(-_S_alignment));
}
_GLIBCXX_ALWAYS_INLINE void
store(__int_type __i, memory_order __m = memory_order_seq_cst) noexcept
{
memory_order __b __attribute__ ((__unused__))
= __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, int(__m));
}
_GLIBCXX_ALWAYS_INLINE void
store(__int_type __i,
memory_order __m = memory_order_seq_cst) volatile noexcept
{
memory_order __b __attribute__ ((__unused__))
= __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, int(__m));
}
_GLIBCXX_ALWAYS_INLINE __int_type
load(memory_order __m = memory_order_seq_cst) const noexcept
{
memory_order __b __attribute__ ((__unused__))
= __m & __memory_order_mask;
__glibcxx_assert(__b != memory_order_release);
__glibcxx_assert(__b != memory_order_acq_rel);
return __atomic_load_n(&_M_i, int(__m));
}
_GLIBCXX_ALWAYS_INLINE __int_type
load(memory_order __m = memory_order_seq_cst) const volatile noexcept
{
memory_order __b __attribute__ ((__unused__))
= __m & __memory_order_mask;
__glibcxx_assert(__b != memory_order_release);
__glibcxx_assert(__b != memory_order_acq_rel);
return __atomic_load_n(&_M_i, int(__m));
}
_GLIBCXX_ALWAYS_INLINE __int_type
exchange(__int_type __i,
memory_order __m = memory_order_seq_cst) noexcept
{
return __atomic_exchange_n(&_M_i, __i, int(__m));
}
_GLIBCXX_ALWAYS_INLINE __int_type
exchange(__int_type __i,
memory_order __m = memory_order_seq_cst) volatile noexcept
{
return __atomic_exchange_n(&_M_i, __i, int(__m));
}
_GLIBCXX_ALWAYS_INLINE bool
compare_exchange_weak(__int_type& __i1, __int_type __i2,
memory_order __m1, memory_order __m2) noexcept
{
__glibcxx_assert(__is_valid_cmpexch_failure_order(__m2));
return __atomic_compare_exchange_n(&_M_i, &__i1, __i2, 1,
int(__m1), int(__m2));
}
_GLIBCXX_ALWAYS_INLINE bool
compare_exchange_weak(__int_type& __i1, __int_type __i2,
memory_order __m1,
memory_order __m2) volatile noexcept
{
__glibcxx_assert(__is_valid_cmpexch_failure_order(__m2));
return __atomic_compare_exchange_n(&_M_i, &__i1, __i2, 1,
int(__m1), int(__m2));
}
_GLIBCXX_ALWAYS_INLINE 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));
}
_GLIBCXX_ALWAYS_INLINE 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));
}
_GLIBCXX_ALWAYS_INLINE bool
compare_exchange_strong(__int_type& __i1, __int_type __i2,
memory_order __m1, memory_order __m2) noexcept
{
__glibcxx_assert(__is_valid_cmpexch_failure_order(__m2));
return __atomic_compare_exchange_n(&_M_i, &__i1, __i2, 0,
int(__m1), int(__m2));
}
_GLIBCXX_ALWAYS_INLINE bool
compare_exchange_strong(__int_type& __i1, __int_type __i2,
memory_order __m1,
memory_order __m2) volatile noexcept
{
__glibcxx_assert(__is_valid_cmpexch_failure_order(__m2));
return __atomic_compare_exchange_n(&_M_i, &__i1, __i2, 0,
int(__m1), int(__m2));
}
_GLIBCXX_ALWAYS_INLINE 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));
}
_GLIBCXX_ALWAYS_INLINE 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));
}
#if __cpp_lib_atomic_wait
_GLIBCXX_ALWAYS_INLINE void
wait(__int_type __old,
memory_order __m = memory_order_seq_cst) const noexcept
{
std::__atomic_wait_address_v(&_M_i, __old,
[__m, this] { return this->load(__m); });
}
// TODO add const volatile overload
_GLIBCXX_ALWAYS_INLINE void
notify_one() noexcept
{ std::__atomic_notify_address(&_M_i, false); }
// TODO add const volatile overload
_GLIBCXX_ALWAYS_INLINE void
notify_all() noexcept
{ std::__atomic_notify_address(&_M_i, true); }
// TODO add const volatile overload
#endif // __cpp_lib_atomic_wait
_GLIBCXX_ALWAYS_INLINE __int_type
fetch_add(__int_type __i,
memory_order __m = memory_order_seq_cst) noexcept
{ return __atomic_fetch_add(&_M_i, __i, int(__m)); }
_GLIBCXX_ALWAYS_INLINE __int_type
fetch_add(__int_type __i,
memory_order __m = memory_order_seq_cst) volatile noexcept
{ return __atomic_fetch_add(&_M_i, __i, int(__m)); }
_GLIBCXX_ALWAYS_INLINE __int_type
fetch_sub(__int_type __i,
memory_order __m = memory_order_seq_cst) noexcept
{ return __atomic_fetch_sub(&_M_i, __i, int(__m)); }
_GLIBCXX_ALWAYS_INLINE __int_type
fetch_sub(__int_type __i,
memory_order __m = memory_order_seq_cst) volatile noexcept
{ return __atomic_fetch_sub(&_M_i, __i, int(__m)); }
_GLIBCXX_ALWAYS_INLINE __int_type
fetch_and(__int_type __i,
memory_order __m = memory_order_seq_cst) noexcept
{ return __atomic_fetch_and(&_M_i, __i, int(__m)); }
_GLIBCXX_ALWAYS_INLINE __int_type
fetch_and(__int_type __i,
memory_order __m = memory_order_seq_cst) volatile noexcept
{ return __atomic_fetch_and(&_M_i, __i, int(__m)); }
_GLIBCXX_ALWAYS_INLINE __int_type
fetch_or(__int_type __i,
memory_order __m = memory_order_seq_cst) noexcept
{ return __atomic_fetch_or(&_M_i, __i, int(__m)); }
_GLIBCXX_ALWAYS_INLINE __int_type
fetch_or(__int_type __i,
memory_order __m = memory_order_seq_cst) volatile noexcept
{ return __atomic_fetch_or(&_M_i, __i, int(__m)); }
_GLIBCXX_ALWAYS_INLINE __int_type
fetch_xor(__int_type __i,
memory_order __m = memory_order_seq_cst) noexcept
{ return __atomic_fetch_xor(&_M_i, __i, int(__m)); }
_GLIBCXX_ALWAYS_INLINE __int_type
fetch_xor(__int_type __i,
memory_order __m = memory_order_seq_cst) volatile noexcept
{ return __atomic_fetch_xor(&_M_i, __i, int(__m)); }
};
/// Partial specialization for pointer types.
template<typename _PTp>
struct __atomic_base<_PTp*>
{
private:
typedef _PTp* __pointer_type;
__pointer_type _M_p _GLIBCXX20_INIT(nullptr);
// Factored out to facilitate explicit specialization.
constexpr ptrdiff_t
_M_type_size(ptrdiff_t __d) const { return __d * sizeof(_PTp); }
constexpr ptrdiff_t
_M_type_size(ptrdiff_t __d) const 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),
int(memory_order_seq_cst)); }
__pointer_type
operator++() volatile noexcept
{ return __atomic_add_fetch(&_M_p, _M_type_size(1),
int(memory_order_seq_cst)); }
__pointer_type
operator--() noexcept
{ return __atomic_sub_fetch(&_M_p, _M_type_size(1),
int(memory_order_seq_cst)); }
__pointer_type
operator--() volatile noexcept
{ return __atomic_sub_fetch(&_M_p, _M_type_size(1),
int(memory_order_seq_cst)); }
__pointer_type
operator+=(ptrdiff_t __d) noexcept
{ return __atomic_add_fetch(&_M_p, _M_type_size(__d),
int(memory_order_seq_cst)); }
__pointer_type
operator+=(ptrdiff_t __d) volatile noexcept
{ return __atomic_add_fetch(&_M_p, _M_type_size(__d),
int(memory_order_seq_cst)); }
__pointer_type
operator-=(ptrdiff_t __d) noexcept
{ return __atomic_sub_fetch(&_M_p, _M_type_size(__d),
int(memory_order_seq_cst)); }
__pointer_type
operator-=(ptrdiff_t __d) volatile noexcept
{ return __atomic_sub_fetch(&_M_p, _M_type_size(__d),
int(memory_order_seq_cst)); }
bool
is_lock_free() const noexcept
{
// Produce a fake, minimally aligned pointer.
return __atomic_is_lock_free(sizeof(_M_p),
reinterpret_cast<void *>(-__alignof(_M_p)));
}
bool
is_lock_free() const volatile noexcept
{
// Produce a fake, minimally aligned pointer.
return __atomic_is_lock_free(sizeof(_M_p),
reinterpret_cast<void *>(-__alignof(_M_p)));
}
_GLIBCXX_ALWAYS_INLINE void
store(__pointer_type __p,
memory_order __m = memory_order_seq_cst) noexcept
{
memory_order __b __attribute__ ((__unused__))
= __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, int(__m));
}
_GLIBCXX_ALWAYS_INLINE void
store(__pointer_type __p,
memory_order __m = memory_order_seq_cst) volatile noexcept
{
memory_order __b __attribute__ ((__unused__))
= __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, int(__m));
}
_GLIBCXX_ALWAYS_INLINE __pointer_type
load(memory_order __m = memory_order_seq_cst) const noexcept
{
memory_order __b __attribute__ ((__unused__))
= __m & __memory_order_mask;
__glibcxx_assert(__b != memory_order_release);
__glibcxx_assert(__b != memory_order_acq_rel);
return __atomic_load_n(&_M_p, int(__m));
}
_GLIBCXX_ALWAYS_INLINE __pointer_type
load(memory_order __m = memory_order_seq_cst) const volatile noexcept
{
memory_order __b __attribute__ ((__unused__))
= __m & __memory_order_mask;
__glibcxx_assert(__b != memory_order_release);
__glibcxx_assert(__b != memory_order_acq_rel);
return __atomic_load_n(&_M_p, int(__m));
}
_GLIBCXX_ALWAYS_INLINE __pointer_type
exchange(__pointer_type __p,
memory_order __m = memory_order_seq_cst) noexcept
{
return __atomic_exchange_n(&_M_p, __p, int(__m));
}
_GLIBCXX_ALWAYS_INLINE __pointer_type
exchange(__pointer_type __p,
memory_order __m = memory_order_seq_cst) volatile noexcept
{
return __atomic_exchange_n(&_M_p, __p, int(__m));
}
_GLIBCXX_ALWAYS_INLINE bool
compare_exchange_strong(__pointer_type& __p1, __pointer_type __p2,
memory_order __m1,
memory_order __m2) noexcept
{
__glibcxx_assert(__is_valid_cmpexch_failure_order(__m2));
return __atomic_compare_exchange_n(&_M_p, &__p1, __p2, 0,
int(__m1), int(__m2));
}
_GLIBCXX_ALWAYS_INLINE bool
compare_exchange_strong(__pointer_type& __p1, __pointer_type __p2,
memory_order __m1,
memory_order __m2) volatile noexcept
{
__glibcxx_assert(__is_valid_cmpexch_failure_order(__m2));
return __atomic_compare_exchange_n(&_M_p, &__p1, __p2, 0,
int(__m1), int(__m2));
}
#if __cpp_lib_atomic_wait
_GLIBCXX_ALWAYS_INLINE void
wait(__pointer_type __old,
memory_order __m = memory_order_seq_cst) const noexcept
{
std::__atomic_wait_address_v(&_M_p, __old,
[__m, this]
{ return this->load(__m); });
}
// TODO add const volatile overload
_GLIBCXX_ALWAYS_INLINE void
notify_one() const noexcept
{ std::__atomic_notify_address(&_M_p, false); }
// TODO add const volatile overload
_GLIBCXX_ALWAYS_INLINE void
notify_all() const noexcept
{ std::__atomic_notify_address(&_M_p, true); }
// TODO add const volatile overload
#endif // __cpp_lib_atomic_wait
_GLIBCXX_ALWAYS_INLINE __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), int(__m)); }
_GLIBCXX_ALWAYS_INLINE __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), int(__m)); }
_GLIBCXX_ALWAYS_INLINE __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), int(__m)); }
_GLIBCXX_ALWAYS_INLINE __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), int(__m)); }
};
#if __cplusplus > 201703L
// Implementation details of atomic_ref and atomic<floating-point>.
namespace __atomic_impl
{
// Remove volatile and create a non-deduced context for value arguments.
template<typename _Tp>
using _Val = remove_volatile_t<_Tp>;
// As above, but for difference_type arguments.
template<typename _Tp>
using _Diff = conditional_t<is_pointer_v<_Tp>, ptrdiff_t, _Val<_Tp>>;
template<size_t _Size, size_t _Align>
_GLIBCXX_ALWAYS_INLINE bool
is_lock_free() noexcept
{
// Produce a fake, minimally aligned pointer.
return __atomic_is_lock_free(_Size, reinterpret_cast<void *>(-_Align));
}
template<typename _Tp>
_GLIBCXX_ALWAYS_INLINE void
store(_Tp* __ptr, _Val<_Tp> __t, memory_order __m) noexcept
{ __atomic_store(__ptr, std::__addressof(__t), int(__m)); }
template<typename _Tp>
_GLIBCXX_ALWAYS_INLINE _Val<_Tp>
load(const _Tp* __ptr, memory_order __m) noexcept
{
alignas(_Tp) unsigned char __buf[sizeof(_Tp)];
auto* __dest = reinterpret_cast<_Val<_Tp>*>(__buf);
__atomic_load(__ptr, __dest, int(__m));
return *__dest;
}
template<typename _Tp>
_GLIBCXX_ALWAYS_INLINE _Val<_Tp>
exchange(_Tp* __ptr, _Val<_Tp> __desired, memory_order __m) noexcept
{
alignas(_Tp) unsigned char __buf[sizeof(_Tp)];
auto* __dest = reinterpret_cast<_Val<_Tp>*>(__buf);
__atomic_exchange(__ptr, std::__addressof(__desired), __dest, int(__m));
return *__dest;
}
template<typename _Tp>
_GLIBCXX_ALWAYS_INLINE bool
compare_exchange_weak(_Tp* __ptr, _Val<_Tp>& __expected,
_Val<_Tp> __desired, memory_order __success,
memory_order __failure) noexcept
{
__glibcxx_assert(__is_valid_cmpexch_failure_order(__failure));
return __atomic_compare_exchange(__ptr, std::__addressof(__expected),
std::__addressof(__desired), true,
int(__success), int(__failure));
}
template<typename _Tp>
_GLIBCXX_ALWAYS_INLINE bool
compare_exchange_strong(_Tp* __ptr, _Val<_Tp>& __expected,
_Val<_Tp> __desired, memory_order __success,
memory_order __failure) noexcept
{
__glibcxx_assert(__is_valid_cmpexch_failure_order(__failure));
return __atomic_compare_exchange(__ptr, std::__addressof(__expected),
std::__addressof(__desired), false,
int(__success), int(__failure));
}
#if __cpp_lib_atomic_wait
template<typename _Tp>
_GLIBCXX_ALWAYS_INLINE void
wait(const _Tp* __ptr, _Val<_Tp> __old,
memory_order __m = memory_order_seq_cst) noexcept
{
std::__atomic_wait_address_v(__ptr, __old,
[__ptr, __m]() { return __atomic_impl::load(__ptr, __m); });
}
// TODO add const volatile overload
template<typename _Tp>
_GLIBCXX_ALWAYS_INLINE void
notify_one(const _Tp* __ptr) noexcept
{ std::__atomic_notify_address(__ptr, false); }
// TODO add const volatile overload
template<typename _Tp>
_GLIBCXX_ALWAYS_INLINE void
notify_all(const _Tp* __ptr) noexcept
{ std::__atomic_notify_address(__ptr, true); }
// TODO add const volatile overload
#endif // __cpp_lib_atomic_wait
template<typename _Tp>
_GLIBCXX_ALWAYS_INLINE _Tp
fetch_add(_Tp* __ptr, _Diff<_Tp> __i, memory_order __m) noexcept
{ return __atomic_fetch_add(__ptr, __i, int(__m)); }
template<typename _Tp>
_GLIBCXX_ALWAYS_INLINE _Tp
fetch_sub(_Tp* __ptr, _Diff<_Tp> __i, memory_order __m) noexcept
{ return __atomic_fetch_sub(__ptr, __i, int(__m)); }
template<typename _Tp>
_GLIBCXX_ALWAYS_INLINE _Tp
fetch_and(_Tp* __ptr, _Val<_Tp> __i, memory_order __m) noexcept
{ return __atomic_fetch_and(__ptr, __i, int(__m)); }
template<typename _Tp>
_GLIBCXX_ALWAYS_INLINE _Tp
fetch_or(_Tp* __ptr, _Val<_Tp> __i, memory_order __m) noexcept
{ return __atomic_fetch_or(__ptr, __i, int(__m)); }
template<typename _Tp>
_GLIBCXX_ALWAYS_INLINE _Tp
fetch_xor(_Tp* __ptr, _Val<_Tp> __i, memory_order __m) noexcept
{ return __atomic_fetch_xor(__ptr, __i, int(__m)); }
template<typename _Tp>
_GLIBCXX_ALWAYS_INLINE _Tp
__add_fetch(_Tp* __ptr, _Diff<_Tp> __i) noexcept
{ return __atomic_add_fetch(__ptr, __i, __ATOMIC_SEQ_CST); }
template<typename _Tp>
_GLIBCXX_ALWAYS_INLINE _Tp
__sub_fetch(_Tp* __ptr, _Diff<_Tp> __i) noexcept
{ return __atomic_sub_fetch(__ptr, __i, __ATOMIC_SEQ_CST); }
template<typename _Tp>
_GLIBCXX_ALWAYS_INLINE _Tp
__and_fetch(_Tp* __ptr, _Val<_Tp> __i) noexcept
{ return __atomic_and_fetch(__ptr, __i, __ATOMIC_SEQ_CST); }
template<typename _Tp>
_GLIBCXX_ALWAYS_INLINE _Tp
__or_fetch(_Tp* __ptr, _Val<_Tp> __i) noexcept
{ return __atomic_or_fetch(__ptr, __i, __ATOMIC_SEQ_CST); }
template<typename _Tp>
_GLIBCXX_ALWAYS_INLINE _Tp
__xor_fetch(_Tp* __ptr, _Val<_Tp> __i) noexcept
{ return __atomic_xor_fetch(__ptr, __i, __ATOMIC_SEQ_CST); }
template<typename _Tp>
_Tp
__fetch_add_flt(_Tp* __ptr, _Val<_Tp> __i, memory_order __m) noexcept
{
_Val<_Tp> __oldval = load(__ptr, memory_order_relaxed);
_Val<_Tp> __newval = __oldval + __i;
while (!compare_exchange_weak(__ptr, __oldval, __newval, __m,
memory_order_relaxed))
__newval = __oldval + __i;
return __oldval;
}
template<typename _Tp>
_Tp
__fetch_sub_flt(_Tp* __ptr, _Val<_Tp> __i, memory_order __m) noexcept
{
_Val<_Tp> __oldval = load(__ptr, memory_order_relaxed);
_Val<_Tp> __newval = __oldval - __i;
while (!compare_exchange_weak(__ptr, __oldval, __newval, __m,
memory_order_relaxed))
__newval = __oldval - __i;
return __oldval;
}
template<typename _Tp>
_Tp
__add_fetch_flt(_Tp* __ptr, _Val<_Tp> __i) noexcept
{
_Val<_Tp> __oldval = load(__ptr, memory_order_relaxed);
_Val<_Tp> __newval = __oldval + __i;
while (!compare_exchange_weak(__ptr, __oldval, __newval,
memory_order_seq_cst,
memory_order_relaxed))
__newval = __oldval + __i;
return __newval;
}
template<typename _Tp>
_Tp
__sub_fetch_flt(_Tp* __ptr, _Val<_Tp> __i) noexcept
{
_Val<_Tp> __oldval = load(__ptr, memory_order_relaxed);
_Val<_Tp> __newval = __oldval - __i;
while (!compare_exchange_weak(__ptr, __oldval, __newval,
memory_order_seq_cst,
memory_order_relaxed))
__newval = __oldval - __i;
return __newval;
}
} // namespace __atomic_impl
// base class for atomic<floating-point-type>
template<typename _Fp>
struct __atomic_float
{
static_assert(is_floating_point_v<_Fp>);
static constexpr size_t _S_alignment = __alignof__(_Fp);
public:
using value_type = _Fp;
using difference_type = value_type;
static constexpr bool is_always_lock_free
= __atomic_always_lock_free(sizeof(_Fp), 0);
__atomic_float() = default;
constexpr
__atomic_float(_Fp __t) : _M_fp(__t)
{ }
__atomic_float(const __atomic_float&) = delete;
__atomic_float& operator=(const __atomic_float&) = delete;
__atomic_float& operator=(const __atomic_float&) volatile = delete;
_Fp
operator=(_Fp __t) volatile noexcept
{
this->store(__t);
return __t;
}
_Fp
operator=(_Fp __t) noexcept
{
this->store(__t);
return __t;
}
bool
is_lock_free() const volatile noexcept
{ return __atomic_impl::is_lock_free<sizeof(_Fp), _S_alignment>(); }
bool
is_lock_free() const noexcept
{ return __atomic_impl::is_lock_free<sizeof(_Fp), _S_alignment>(); }
void
store(_Fp __t, memory_order __m = memory_order_seq_cst) volatile noexcept
{ __atomic_impl::store(&_M_fp, __t, __m); }
void
store(_Fp __t, memory_order __m = memory_order_seq_cst) noexcept
{ __atomic_impl::store(&_M_fp, __t, __m); }
_Fp
load(memory_order __m = memory_order_seq_cst) const volatile noexcept
{ return __atomic_impl::load(&_M_fp, __m); }
_Fp
load(memory_order __m = memory_order_seq_cst) const noexcept
{ return __atomic_impl::load(&_M_fp, __m); }
operator _Fp() const volatile noexcept { return this->load(); }
operator _Fp() const noexcept { return this->load(); }
_Fp
exchange(_Fp __desired,
memory_order __m = memory_order_seq_cst) volatile noexcept
{ return __atomic_impl::exchange(&_M_fp, __desired, __m); }
_Fp
exchange(_Fp __desired,
memory_order __m = memory_order_seq_cst) noexcept
{ return __atomic_impl::exchange(&_M_fp, __desired, __m); }
bool
compare_exchange_weak(_Fp& __expected, _Fp __desired,
memory_order __success,
memory_order __failure) noexcept
{
return __atomic_impl::compare_exchange_weak(&_M_fp,
__expected, __desired,
__success, __failure);
}
bool
compare_exchange_weak(_Fp& __expected, _Fp __desired,
memory_order __success,
memory_order __failure) volatile noexcept
{
return __atomic_impl::compare_exchange_weak(&_M_fp,
__expected, __desired,
__success, __failure);
}
bool
compare_exchange_strong(_Fp& __expected, _Fp __desired,
memory_order __success,
memory_order __failure) noexcept
{
return __atomic_impl::compare_exchange_strong(&_M_fp,
__expected, __desired,
__success, __failure);
}
bool
compare_exchange_strong(_Fp& __expected, _Fp __desired,
memory_order __success,
memory_order __failure) volatile noexcept
{
return __atomic_impl::compare_exchange_strong(&_M_fp,
__expected, __desired,
__success, __failure);
}
bool
compare_exchange_weak(_Fp& __expected, _Fp __desired,
memory_order __order = memory_order_seq_cst)
noexcept
{
return compare_exchange_weak(__expected, __desired, __order,
__cmpexch_failure_order(__order));
}
bool
compare_exchange_weak(_Fp& __expected, _Fp __desired,
memory_order __order = memory_order_seq_cst)
volatile noexcept
{
return compare_exchange_weak(__expected, __desired, __order,
__cmpexch_failure_order(__order));
}
bool
compare_exchange_strong(_Fp& __expected, _Fp __desired,
memory_order __order = memory_order_seq_cst)
noexcept
{
return compare_exchange_strong(__expected, __desired, __order,
__cmpexch_failure_order(__order));
}
bool
compare_exchange_strong(_Fp& __expected, _Fp __desired,
memory_order __order = memory_order_seq_cst)
volatile noexcept
{
return compare_exchange_strong(__expected, __desired, __order,
__cmpexch_failure_order(__order));
}
#if __cpp_lib_atomic_wait
_GLIBCXX_ALWAYS_INLINE void
wait(_Fp __old, memory_order __m = memory_order_seq_cst) const noexcept
{ __atomic_impl::wait(&_M_fp, __old, __m); }
// TODO add const volatile overload
_GLIBCXX_ALWAYS_INLINE void
notify_one() const noexcept
{ __atomic_impl::notify_one(&_M_fp); }
// TODO add const volatile overload
_GLIBCXX_ALWAYS_INLINE void
notify_all() const noexcept
{ __atomic_impl::notify_all(&_M_fp); }
// TODO add const volatile overload
#endif // __cpp_lib_atomic_wait
value_type
fetch_add(value_type __i,
memory_order __m = memory_order_seq_cst) noexcept
{ return __atomic_impl::__fetch_add_flt(&_M_fp, __i, __m); }
value_type
fetch_add(value_type __i,
memory_order __m = memory_order_seq_cst) volatile noexcept
{ return __atomic_impl::__fetch_add_flt(&_M_fp, __i, __m); }
value_type
fetch_sub(value_type __i,
memory_order __m = memory_order_seq_cst) noexcept
{ return __atomic_impl::__fetch_sub_flt(&_M_fp, __i, __m); }
value_type
fetch_sub(value_type __i,
memory_order __m = memory_order_seq_cst) volatile noexcept
{ return __atomic_impl::__fetch_sub_flt(&_M_fp, __i, __m); }
value_type
operator+=(value_type __i) noexcept
{ return __atomic_impl::__add_fetch_flt(&_M_fp, __i); }
value_type
operator+=(value_type __i) volatile noexcept
{ return __atomic_impl::__add_fetch_flt(&_M_fp, __i); }
value_type
operator-=(value_type __i) noexcept
{ return __atomic_impl::__sub_fetch_flt(&_M_fp, __i); }
value_type
operator-=(value_type __i) volatile noexcept
{ return __atomic_impl::__sub_fetch_flt(&_M_fp, __i); }
private:
alignas(_S_alignment) _Fp _M_fp _GLIBCXX20_INIT(0);
};
#undef _GLIBCXX20_INIT
template<typename _Tp,
bool = is_integral_v<_Tp>, bool = is_floating_point_v<_Tp>>
struct __atomic_ref;
// base class for non-integral, non-floating-point, non-pointer types
template<typename _Tp>
struct __atomic_ref<_Tp, false, false>
{
static_assert(is_trivially_copyable_v<_Tp>);
// 1/2/4/8/16-byte types must be aligned to at least their size.
static constexpr int _S_min_alignment
= (sizeof(_Tp) & (sizeof(_Tp) - 1)) || sizeof(_Tp) > 16
? 0 : sizeof(_Tp);
public:
using value_type = _Tp;
static constexpr bool is_always_lock_free
= __atomic_always_lock_free(sizeof(_Tp), 0);
static constexpr size_t required_alignment
= _S_min_alignment > alignof(_Tp) ? _S_min_alignment : alignof(_Tp);
__atomic_ref& operator=(const __atomic_ref&) = delete;
explicit
__atomic_ref(_Tp& __t) : _M_ptr(std::__addressof(__t))
{ __glibcxx_assert(((uintptr_t)_M_ptr % required_alignment) == 0); }
__atomic_ref(const __atomic_ref&) noexcept = default;
_Tp
operator=(_Tp __t) const noexcept
{
this->store(__t);
return __t;
}
operator _Tp() const noexcept { return this->load(); }
bool
is_lock_free() const noexcept
{ return __atomic_impl::is_lock_free<sizeof(_Tp), required_alignment>(); }
void
store(_Tp __t, memory_order __m = memory_order_seq_cst) const noexcept
{ __atomic_impl::store(_M_ptr, __t, __m); }
_Tp
load(memory_order __m = memory_order_seq_cst) const noexcept
{ return __atomic_impl::load(_M_ptr, __m); }
_Tp
exchange(_Tp __desired, memory_order __m = memory_order_seq_cst)
const noexcept
{ return __atomic_impl::exchange(_M_ptr, __desired, __m); }
bool
compare_exchange_weak(_Tp& __expected, _Tp __desired,
memory_order __success,
memory_order __failure) const noexcept
{
return __atomic_impl::compare_exchange_weak(_M_ptr,
__expected, __desired,
__success, __failure);
}
bool
compare_exchange_strong(_Tp& __expected, _Tp __desired,
memory_order __success,
memory_order __failure) const noexcept
{
return __atomic_impl::compare_exchange_strong(_M_ptr,
__expected, __desired,
__success, __failure);
}
bool
compare_exchange_weak(_Tp& __expected, _Tp __desired,
memory_order __order = memory_order_seq_cst)
const noexcept
{
return compare_exchange_weak(__expected, __desired, __order,
__cmpexch_failure_order(__order));
}
bool
compare_exchange_strong(_Tp& __expected, _Tp __desired,
memory_order __order = memory_order_seq_cst)
const noexcept
{
return compare_exchange_strong(__expected, __desired, __order,
__cmpexch_failure_order(__order));
}
#if __cpp_lib_atomic_wait
_GLIBCXX_ALWAYS_INLINE void
wait(_Tp __old, memory_order __m = memory_order_seq_cst) const noexcept
{ __atomic_impl::wait(_M_ptr, __old, __m); }
// TODO add const volatile overload
_GLIBCXX_ALWAYS_INLINE void
notify_one() const noexcept
{ __atomic_impl::notify_one(_M_ptr); }
// TODO add const volatile overload
_GLIBCXX_ALWAYS_INLINE void
notify_all() const noexcept
{ __atomic_impl::notify_all(_M_ptr); }
// TODO add const volatile overload
#endif // __cpp_lib_atomic_wait
private:
_Tp* _M_ptr;
};
// base class for atomic_ref<integral-type>
template<typename _Tp>
struct __atomic_ref<_Tp, true, false>
{
static_assert(is_integral_v<_Tp>);
public:
using value_type = _Tp;
using difference_type = value_type;
static constexpr bool is_always_lock_free
= __atomic_always_lock_free(sizeof(_Tp), 0);
static constexpr size_t required_alignment
= sizeof(_Tp) > alignof(_Tp) ? sizeof(_Tp) : alignof(_Tp);
__atomic_ref() = delete;
__atomic_ref& operator=(const __atomic_ref&) = delete;
explicit
__atomic_ref(_Tp& __t) : _M_ptr(&__t)
{ __glibcxx_assert(((uintptr_t)_M_ptr % required_alignment) == 0); }
__atomic_ref(const __atomic_ref&) noexcept = default;
_Tp
operator=(_Tp __t) const noexcept
{
this->store(__t);
return __t;
}
operator _Tp() const noexcept { return this->load(); }
bool
is_lock_free() const noexcept
{
return __atomic_impl::is_lock_free<sizeof(_Tp), required_alignment>();
}
void
store(_Tp __t, memory_order __m = memory_order_seq_cst) const noexcept
{ __atomic_impl::store(_M_ptr, __t, __m); }
_Tp
load(memory_order __m = memory_order_seq_cst) const noexcept
{ return __atomic_impl::load(_M_ptr, __m); }
_Tp
exchange(_Tp __desired,
memory_order __m = memory_order_seq_cst) const noexcept
{ return __atomic_impl::exchange(_M_ptr, __desired, __m); }
bool
compare_exchange_weak(_Tp& __expected, _Tp __desired,
memory_order __success,
memory_order __failure) const noexcept
{
return __atomic_impl::compare_exchange_weak(_M_ptr,
__expected, __desired,
__success, __failure);
}
bool
compare_exchange_strong(_Tp& __expected, _Tp __desired,
memory_order __success,
memory_order __failure) const noexcept
{
return __atomic_impl::compare_exchange_strong(_M_ptr,
__expected, __desired,
__success, __failure);
}
bool
compare_exchange_weak(_Tp& __expected, _Tp __desired,
memory_order __order = memory_order_seq_cst)
const noexcept
{
return compare_exchange_weak(__expected, __desired, __order,
__cmpexch_failure_order(__order));
}
bool
compare_exchange_strong(_Tp& __expected, _Tp __desired,
memory_order __order = memory_order_seq_cst)
const noexcept
{
return compare_exchange_strong(__expected, __desired, __order,
__cmpexch_failure_order(__order));
}
#if __cpp_lib_atomic_wait
_GLIBCXX_ALWAYS_INLINE void
wait(_Tp __old, memory_order __m = memory_order_seq_cst) const noexcept
{ __atomic_impl::wait(_M_ptr, __old, __m); }
// TODO add const volatile overload
_GLIBCXX_ALWAYS_INLINE void
notify_one() const noexcept
{ __atomic_impl::notify_one(_M_ptr); }
// TODO add const volatile overload
_GLIBCXX_ALWAYS_INLINE void
notify_all() const noexcept
{ __atomic_impl::notify_all(_M_ptr); }
// TODO add const volatile overload
#endif // __cpp_lib_atomic_wait
value_type
fetch_add(value_type __i,
memory_order __m = memory_order_seq_cst) const noexcept
{ return __atomic_impl::fetch_add(_M_ptr, __i, __m); }
value_type
fetch_sub(value_type __i,
memory_order __m = memory_order_seq_cst) const noexcept
{ return __atomic_impl::fetch_sub(_M_ptr, __i, __m); }
value_type
fetch_and(value_type __i,
memory_order __m = memory_order_seq_cst) const noexcept
{ return __atomic_impl::fetch_and(_M_ptr, __i, __m); }
value_type
fetch_or(value_type __i,
memory_order __m = memory_order_seq_cst) const noexcept
{ return __atomic_impl::fetch_or(_M_ptr, __i, __m); }
value_type
fetch_xor(value_type __i,
memory_order __m = memory_order_seq_cst) const noexcept
{ return __atomic_impl::fetch_xor(_M_ptr, __i, __m); }
_GLIBCXX_ALWAYS_INLINE value_type
operator++(int) const noexcept
{ return fetch_add(1); }
_GLIBCXX_ALWAYS_INLINE value_type
operator--(int) const noexcept
{ return fetch_sub(1); }
value_type
operator++() const noexcept
{ return __atomic_impl::__add_fetch(_M_ptr, value_type(1)); }
value_type
operator--() const noexcept
{ return __atomic_impl::__sub_fetch(_M_ptr, value_type(1)); }
value_type
operator+=(value_type __i) const noexcept
{ return __atomic_impl::__add_fetch(_M_ptr, __i); }
value_type
operator-=(value_type __i) const noexcept
{ return __atomic_impl::__sub_fetch(_M_ptr, __i); }
value_type
operator&=(value_type __i) const noexcept
{ return __atomic_impl::__and_fetch(_M_ptr, __i); }
value_type
operator|=(value_type __i) const noexcept
{ return __atomic_impl::__or_fetch(_M_ptr, __i); }
value_type
operator^=(value_type __i) const noexcept
{ return __atomic_impl::__xor_fetch(_M_ptr, __i); }
private:
_Tp* _M_ptr;
};
// base class for atomic_ref<floating-point-type>
template<typename _Fp>
struct __atomic_ref<_Fp, false, true>
{
static_assert(is_floating_point_v<_Fp>);
public:
using value_type = _Fp;
using difference_type = value_type;
static constexpr bool is_always_lock_free
= __atomic_always_lock_free(sizeof(_Fp), 0);
static constexpr size_t required_alignment = __alignof__(_Fp);
__atomic_ref() = delete;
__atomic_ref& operator=(const __atomic_ref&) = delete;
explicit
__atomic_ref(_Fp& __t) : _M_ptr(&__t)
{ __glibcxx_assert(((uintptr_t)_M_ptr % required_alignment) == 0); }
__atomic_ref(const __atomic_ref&) noexcept = default;
_Fp
operator=(_Fp __t) const noexcept
{
this->store(__t);
return __t;
}
operator _Fp() const noexcept { return this->load(); }
bool
is_lock_free() const noexcept
{
return __atomic_impl::is_lock_free<sizeof(_Fp), required_alignment>();
}
void
store(_Fp __t, memory_order __m = memory_order_seq_cst) const noexcept
{ __atomic_impl::store(_M_ptr, __t, __m); }
_Fp
load(memory_order __m = memory_order_seq_cst) const noexcept
{ return __atomic_impl::load(_M_ptr, __m); }
_Fp
exchange(_Fp __desired,
memory_order __m = memory_order_seq_cst) const noexcept
{ return __atomic_impl::exchange(_M_ptr, __desired, __m); }
bool
compare_exchange_weak(_Fp& __expected, _Fp __desired,
memory_order __success,
memory_order __failure) const noexcept
{
return __atomic_impl::compare_exchange_weak(_M_ptr,
__expected, __desired,
__success, __failure);
}
bool
compare_exchange_strong(_Fp& __expected, _Fp __desired,
memory_order __success,
memory_order __failure) const noexcept
{
return __atomic_impl::compare_exchange_strong(_M_ptr,
__expected, __desired,
__success, __failure);
}
bool
compare_exchange_weak(_Fp& __expected, _Fp __desired,
memory_order __order = memory_order_seq_cst)
const noexcept
{
return compare_exchange_weak(__expected, __desired, __order,
__cmpexch_failure_order(__order));
}
bool
compare_exchange_strong(_Fp& __expected, _Fp __desired,
memory_order __order = memory_order_seq_cst)
const noexcept
{
return compare_exchange_strong(__expected, __desired, __order,
__cmpexch_failure_order(__order));
}
#if __cpp_lib_atomic_wait
_GLIBCXX_ALWAYS_INLINE void
wait(_Fp __old, memory_order __m = memory_order_seq_cst) const noexcept
{ __atomic_impl::wait(_M_ptr, __old, __m); }
// TODO add const volatile overload
_GLIBCXX_ALWAYS_INLINE void
notify_one() const noexcept
{ __atomic_impl::notify_one(_M_ptr); }
// TODO add const volatile overload
_GLIBCXX_ALWAYS_INLINE void
notify_all() const noexcept
{ __atomic_impl::notify_all(_M_ptr); }
// TODO add const volatile overload
#endif // __cpp_lib_atomic_wait
value_type
fetch_add(value_type __i,
memory_order __m = memory_order_seq_cst) const noexcept
{ return __atomic_impl::__fetch_add_flt(_M_ptr, __i, __m); }
value_type
fetch_sub(value_type __i,
memory_order __m = memory_order_seq_cst) const noexcept
{ return __atomic_impl::__fetch_sub_flt(_M_ptr, __i, __m); }
value_type
operator+=(value_type __i) const noexcept
{ return __atomic_impl::__add_fetch_flt(_M_ptr, __i); }
value_type
operator-=(value_type __i) const noexcept
{ return __atomic_impl::__sub_fetch_flt(_M_ptr, __i); }
private:
_Fp* _M_ptr;
};
// base class for atomic_ref<pointer-type>
template<typename _Tp>
struct __atomic_ref<_Tp*, false, false>
{
public:
using value_type = _Tp*;
using difference_type = ptrdiff_t;
static constexpr bool is_always_lock_free = ATOMIC_POINTER_LOCK_FREE == 2;
static constexpr size_t required_alignment = __alignof__(_Tp*);
__atomic_ref() = delete;
__atomic_ref& operator=(const __atomic_ref&) = delete;
explicit
__atomic_ref(_Tp*& __t) : _M_ptr(std::__addressof(__t))
{ __glibcxx_assert(((uintptr_t)_M_ptr % required_alignment) == 0); }
__atomic_ref(const __atomic_ref&) noexcept = default;
_Tp*
operator=(_Tp* __t) const noexcept
{
this->store(__t);
return __t;
}
operator _Tp*() const noexcept { return this->load(); }
bool
is_lock_free() const noexcept
{
return __atomic_impl::is_lock_free<sizeof(_Tp*), required_alignment>();
}
void
store(_Tp* __t, memory_order __m = memory_order_seq_cst) const noexcept
{ __atomic_impl::store(_M_ptr, __t, __m); }
_Tp*
load(memory_order __m = memory_order_seq_cst) const noexcept
{ return __atomic_impl::load(_M_ptr, __m); }
_Tp*
exchange(_Tp* __desired,
memory_order __m = memory_order_seq_cst) const noexcept
{ return __atomic_impl::exchange(_M_ptr, __desired, __m); }
bool
compare_exchange_weak(_Tp*& __expected, _Tp* __desired,
memory_order __success,
memory_order __failure) const noexcept
{
return __atomic_impl::compare_exchange_weak(_M_ptr,
__expected, __desired,
__success, __failure);
}
bool
compare_exchange_strong(_Tp*& __expected, _Tp* __desired,
memory_order __success,
memory_order __failure) const noexcept
{
return __atomic_impl::compare_exchange_strong(_M_ptr,
__expected, __desired,
__success, __failure);
}
bool
compare_exchange_weak(_Tp*& __expected, _Tp* __desired,
memory_order __order = memory_order_seq_cst)
const noexcept
{
return compare_exchange_weak(__expected, __desired, __order,
__cmpexch_failure_order(__order));
}
bool
compare_exchange_strong(_Tp*& __expected, _Tp* __desired,
memory_order __order = memory_order_seq_cst)
const noexcept
{
return compare_exchange_strong(__expected, __desired, __order,
__cmpexch_failure_order(__order));
}
#if __cpp_lib_atomic_wait
_GLIBCXX_ALWAYS_INLINE void
wait(_Tp* __old, memory_order __m = memory_order_seq_cst) const noexcept
{ __atomic_impl::wait(_M_ptr, __old, __m); }
// TODO add const volatile overload
_GLIBCXX_ALWAYS_INLINE void
notify_one() const noexcept
{ __atomic_impl::notify_one(_M_ptr); }
// TODO add const volatile overload
_GLIBCXX_ALWAYS_INLINE void
notify_all() const noexcept
{ __atomic_impl::notify_all(_M_ptr); }
// TODO add const volatile overload
#endif // __cpp_lib_atomic_wait
_GLIBCXX_ALWAYS_INLINE value_type
fetch_add(difference_type __d,
memory_order __m = memory_order_seq_cst) const noexcept
{ return __atomic_impl::fetch_add(_M_ptr, _S_type_size(__d), __m); }
_GLIBCXX_ALWAYS_INLINE value_type
fetch_sub(difference_type __d,
memory_order __m = memory_order_seq_cst) const noexcept
{ return __atomic_impl::fetch_sub(_M_ptr, _S_type_size(__d), __m); }
value_type
operator++(int) const noexcept
{ return fetch_add(1); }
value_type
operator--(int) const noexcept
{ return fetch_sub(1); }
value_type
operator++() const noexcept
{
return __atomic_impl::__add_fetch(_M_ptr, _S_type_size(1));
}
value_type
operator--() const noexcept
{
return __atomic_impl::__sub_fetch(_M_ptr, _S_type_size(1));
}
value_type
operator+=(difference_type __d) const noexcept
{
return __atomic_impl::__add_fetch(_M_ptr, _S_type_size(__d));
}
value_type
operator-=(difference_type __d) const noexcept
{
return __atomic_impl::__sub_fetch(_M_ptr, _S_type_size(__d));
}
private:
static constexpr ptrdiff_t
_S_type_size(ptrdiff_t __d) noexcept
{
static_assert(is_object_v<_Tp>);
return __d * sizeof(_Tp);
}
_Tp** _M_ptr;
};
#endif // C++2a
/// @} group atomics
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace std
#endif
atomic_lockfree_defines.h
atomic_wait.h
move.h
c++config.h
std::remove_volatile_t
typename remove_volatile< _Tp >::type remove_volatile_t
Alias template for remove_volatile.
Definition type_traits:1572
std::conditional_t
typename conditional< _Cond, _Iftrue, _Iffalse >::type conditional_t
Alias template for conditional.
Definition type_traits:2581
std::__addressof
constexpr _Tp * __addressof(_Tp &__r) noexcept
Same as C++11 std::addressof.
Definition move.h:49
std::memory_order
memory_order
Enumeration for memory_order.
Definition atomic_base.h:79
std::kill_dependency
_Tp kill_dependency(_Tp __y) noexcept
kill_dependency
Definition atomic_base.h:142
std
ISO C++ entities toplevel namespace is std.
std::operator&
bitset< _Nb > operator&(const bitset< _Nb > &__x, const bitset< _Nb > &__y) noexcept
Global bitwise operations on bitsets.
Definition bitset:1435
std::exchange
constexpr _Tp exchange(_Tp &__obj, _Up &&__new_val)
Assign __new_val to __obj and return its previous value.
Definition utility:291
std::operator|
bitset< _Nb > operator|(const bitset< _Nb > &__x, const bitset< _Nb > &__y) noexcept
Global bitwise operations on bitsets.
Definition bitset:1444
std::__atomic_flag_base
Base type for atomic_flag.
Definition atomic_base.h:187
std::value_type