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// -*- C++ -*- header.
// Copyright (C) 2008, 2009, 2010, 2011
// 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_0.h
* This is an internal header file, included by other library headers.
* Do not attempt to use it directly. @headername{atomic}
*/
#ifndef _GLIBCXX_ATOMIC_0_H
#define _GLIBCXX_ATOMIC_0_H 1
#pragma GCC system_header
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
// 0 == __atomic0 == Never lock-free
namespace __atomic0
{
_GLIBCXX_BEGIN_EXTERN_C
void
atomic_flag_clear_explicit(__atomic_flag_base*, memory_order)
_GLIBCXX_NOTHROW;
void
__atomic_flag_wait_explicit(__atomic_flag_base*, memory_order)
_GLIBCXX_NOTHROW;
_GLIBCXX_CONST __atomic_flag_base*
__atomic_flag_for_address(const volatile void* __z) _GLIBCXX_NOTHROW;
_GLIBCXX_END_EXTERN_C
// Implementation specific defines.
#define _ATOMIC_MEMBER_ _M_i
// Implementation specific defines.
#define _ATOMIC_LOAD_(__a, __x) \
({typedef __typeof__(_ATOMIC_MEMBER_) __i_type; \
__i_type* __p = &_ATOMIC_MEMBER_; \
__atomic_flag_base* __g = __atomic_flag_for_address(__p); \
__atomic_flag_wait_explicit(__g, __x); \
__i_type __r = *__p; \
atomic_flag_clear_explicit(__g, __x); \
__r; })
#define _ATOMIC_STORE_(__a, __n, __x) \
({typedef __typeof__(_ATOMIC_MEMBER_) __i_type; \
__i_type* __p = &_ATOMIC_MEMBER_; \
__typeof__(__n) __w = (__n); \
__atomic_flag_base* __g = __atomic_flag_for_address(__p); \
__atomic_flag_wait_explicit(__g, __x); \
*__p = __w; \
atomic_flag_clear_explicit(__g, __x); \
__w; })
#define _ATOMIC_MODIFY_(__a, __o, __n, __x) \
({typedef __typeof__(_ATOMIC_MEMBER_) __i_type; \
__i_type* __p = &_ATOMIC_MEMBER_; \
__typeof__(__n) __w = (__n); \
__atomic_flag_base* __g = __atomic_flag_for_address(__p); \
__atomic_flag_wait_explicit(__g, __x); \
__i_type __r = *__p; \
*__p __o __w; \
atomic_flag_clear_explicit(__g, __x); \
__r; })
#define _ATOMIC_CMPEXCHNG_(__a, __e, __n, __x) \
({typedef __typeof__(_ATOMIC_MEMBER_) __i_type; \
__i_type* __p = &_ATOMIC_MEMBER_; \
__typeof__(__e) __q = (__e); \
__typeof__(__n) __w = (__n); \
bool __r; \
__atomic_flag_base* __g = __atomic_flag_for_address(__p); \
__atomic_flag_wait_explicit(__g, __x); \
__i_type __t = *__p; \
if (*__q == __t) \
{ \
*__p = (__i_type)__w; \
__r = true; \
} \
else { *__q = __t; __r = false; } \
atomic_flag_clear_explicit(__g, __x); \
__r; })
/// atomic_flag
struct atomic_flag : public __atomic_flag_base
{
atomic_flag() = default;
~atomic_flag() = 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.
atomic_flag(bool __i): __atomic_flag_base({ __i }) { }
bool
test_and_set(memory_order __m = memory_order_seq_cst);
bool
test_and_set(memory_order __m = memory_order_seq_cst) volatile;
void
clear(memory_order __m = memory_order_seq_cst);
void
clear(memory_order __m = memory_order_seq_cst) volatile;
};
/// 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
// Base type.
// 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 work on.
template<typename _ITp>
struct __atomic_base
{
private:
typedef _ITp __int_type;
__int_type _M_i;
public:
__atomic_base() = default;
~__atomic_base() = 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_base._M_i.
constexpr __atomic_base(__int_type __i): _M_i (__i) { }
operator __int_type() const
{ return load(); }
operator __int_type() const volatile
{ return load(); }
__int_type
operator=(__int_type __i)
{
store(__i);
return __i;
}
__int_type
operator=(__int_type __i) volatile
{
store(__i);
return __i;
}
__int_type
operator++(int)
{ return fetch_add(1); }
__int_type
operator++(int) volatile
{ return fetch_add(1); }
__int_type
operator--(int)
{ return fetch_sub(1); }
__int_type
operator--(int) volatile
{ return fetch_sub(1); }
__int_type
operator++()
{ return fetch_add(1) + 1; }
__int_type
operator++() volatile
{ return fetch_add(1) + 1; }
__int_type
operator--()
{ return fetch_sub(1) - 1; }
__int_type
operator--() volatile
{ return fetch_sub(1) - 1; }
__int_type
operator+=(__int_type __i)
{ return fetch_add(__i) + __i; }
__int_type
operator+=(__int_type __i) volatile
{ return fetch_add(__i) + __i; }
__int_type
operator-=(__int_type __i)
{ return fetch_sub(__i) - __i; }
__int_type
operator-=(__int_type __i) volatile
{ return fetch_sub(__i) - __i; }
__int_type
operator&=(__int_type __i)
{ return fetch_and(__i) & __i; }
__int_type
operator&=(__int_type __i) volatile
{ return fetch_and(__i) & __i; }
__int_type
operator|=(__int_type __i)
{ return fetch_or(__i) | __i; }
__int_type
operator|=(__int_type __i) volatile
{ return fetch_or(__i) | __i; }
__int_type
operator^=(__int_type __i)
{ return fetch_xor(__i) ^ __i; }
__int_type
operator^=(__int_type __i) volatile
{ return fetch_xor(__i) ^ __i; }
bool
is_lock_free() const
{ return false; }
bool
is_lock_free() const volatile
{ return false; }
void
store(__int_type __i, memory_order __m = memory_order_seq_cst)
{
__glibcxx_assert(__m != memory_order_acquire);
__glibcxx_assert(__m != memory_order_acq_rel);
__glibcxx_assert(__m != memory_order_consume);
_ATOMIC_STORE_(this, __i, __m);
}
void
store(__int_type __i, memory_order __m = memory_order_seq_cst) volatile
{
__glibcxx_assert(__m != memory_order_acquire);
__glibcxx_assert(__m != memory_order_acq_rel);
__glibcxx_assert(__m != memory_order_consume);
_ATOMIC_STORE_(this, __i, __m);
}
__int_type
load(memory_order __m = memory_order_seq_cst) const
{
__glibcxx_assert(__m != memory_order_release);
__glibcxx_assert(__m != memory_order_acq_rel);
return _ATOMIC_LOAD_(this, __m);
}
__int_type
load(memory_order __m = memory_order_seq_cst) const volatile
{
__glibcxx_assert(__m != memory_order_release);
__glibcxx_assert(__m != memory_order_acq_rel);
return _ATOMIC_LOAD_(this, __m);
}
__int_type
exchange(__int_type __i, memory_order __m = memory_order_seq_cst)
{ return _ATOMIC_MODIFY_(this, =, __i, __m); }
__int_type
exchange(__int_type __i, memory_order __m = memory_order_seq_cst) volatile
{ return _ATOMIC_MODIFY_(this, =, __i, __m); }
bool
compare_exchange_weak(__int_type& __i1, __int_type __i2,
memory_order __m1, memory_order __m2)
{
__glibcxx_assert(__m2 != memory_order_release);
__glibcxx_assert(__m2 != memory_order_acq_rel);
__glibcxx_assert(__m2 <= __m1);
return _ATOMIC_CMPEXCHNG_(this, &__i1, __i2, __m1);
}
bool
compare_exchange_weak(__int_type& __i1, __int_type __i2,
memory_order __m1, memory_order __m2) volatile
{
__glibcxx_assert(__m2 != memory_order_release);
__glibcxx_assert(__m2 != memory_order_acq_rel);
__glibcxx_assert(__m2 <= __m1);
return _ATOMIC_CMPEXCHNG_(this, &__i1, __i2, __m1);
}
bool
compare_exchange_weak(__int_type& __i1, __int_type __i2,
memory_order __m = memory_order_seq_cst)
{
return compare_exchange_weak(__i1, __i2, __m,
__calculate_memory_order(__m));
}
bool
compare_exchange_weak(__int_type& __i1, __int_type __i2,
memory_order __m = memory_order_seq_cst) volatile
{
return compare_exchange_weak(__i1, __i2, __m,
__calculate_memory_order(__m));
}
bool
compare_exchange_strong(__int_type& __i1, __int_type __i2,
memory_order __m1, memory_order __m2)
{
__glibcxx_assert(__m2 != memory_order_release);
__glibcxx_assert(__m2 != memory_order_acq_rel);
__glibcxx_assert(__m2 <= __m1);
return _ATOMIC_CMPEXCHNG_(this, &__i1, __i2, __m1);
}
bool
compare_exchange_strong(__int_type& __i1, __int_type __i2,
memory_order __m1, memory_order __m2) volatile
{
__glibcxx_assert(__m2 != memory_order_release);
__glibcxx_assert(__m2 != memory_order_acq_rel);
__glibcxx_assert(__m2 <= __m1);
return _ATOMIC_CMPEXCHNG_(this, &__i1, __i2, __m1);
}
bool
compare_exchange_strong(__int_type& __i1, __int_type __i2,
memory_order __m = memory_order_seq_cst)
{
return compare_exchange_strong(__i1, __i2, __m,
__calculate_memory_order(__m));
}
bool
compare_exchange_strong(__int_type& __i1, __int_type __i2,
memory_order __m = memory_order_seq_cst) volatile
{
return compare_exchange_strong(__i1, __i2, __m,
__calculate_memory_order(__m));
}
__int_type
fetch_add(__int_type __i, memory_order __m = memory_order_seq_cst)
{ return _ATOMIC_MODIFY_(this, +=, __i, __m); }
__int_type
fetch_add(__int_type __i,
memory_order __m = memory_order_seq_cst) volatile
{ return _ATOMIC_MODIFY_(this, +=, __i, __m); }
__int_type
fetch_sub(__int_type __i, memory_order __m = memory_order_seq_cst)
{ return _ATOMIC_MODIFY_(this, -=, __i, __m); }
__int_type
fetch_sub(__int_type __i,
memory_order __m = memory_order_seq_cst) volatile
{ return _ATOMIC_MODIFY_(this, -=, __i, __m); }
__int_type
fetch_and(__int_type __i, memory_order __m = memory_order_seq_cst)
{ return _ATOMIC_MODIFY_(this, &=, __i, __m); }
__int_type
fetch_and(__int_type __i,
memory_order __m = memory_order_seq_cst) volatile
{ return _ATOMIC_MODIFY_(this, &=, __i, __m); }
__int_type
fetch_or(__int_type __i, memory_order __m = memory_order_seq_cst)
{ return _ATOMIC_MODIFY_(this, |=, __i, __m); }
__int_type
fetch_or(__int_type __i, memory_order __m = memory_order_seq_cst) volatile
{ return _ATOMIC_MODIFY_(this, |=, __i, __m); }
__int_type
fetch_xor(__int_type __i, memory_order __m = memory_order_seq_cst)
{ return _ATOMIC_MODIFY_(this, ^=, __i, __m); }
__int_type
fetch_xor(__int_type __i,
memory_order __m = memory_order_seq_cst) volatile
{ return _ATOMIC_MODIFY_(this, ^=, __i, __m); }
};
/// Partial specialization for pointer types.
template<typename _PTp>
struct __atomic_base<_PTp*>
{
private:
typedef _PTp* __return_pointer_type;
typedef void* __pointer_type;
__pointer_type _M_i;
public:
__atomic_base() = default;
~__atomic_base() = 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_i.
constexpr __atomic_base(__return_pointer_type __p): _M_i (__p) { }
operator __return_pointer_type() const
{ return reinterpret_cast<__return_pointer_type>(load()); }
operator __return_pointer_type() const volatile
{ return reinterpret_cast<__return_pointer_type>(load()); }
__return_pointer_type
operator=(__pointer_type __p)
{
store(__p);
return reinterpret_cast<__return_pointer_type>(__p);
}
__return_pointer_type
operator=(__pointer_type __p) volatile
{
store(__p);
return reinterpret_cast<__return_pointer_type>(__p);
}
__return_pointer_type
operator++(int)
{ return reinterpret_cast<__return_pointer_type>(fetch_add(1)); }
__return_pointer_type
operator++(int) volatile
{ return reinterpret_cast<__return_pointer_type>(fetch_add(1)); }
__return_pointer_type
operator--(int)
{ return reinterpret_cast<__return_pointer_type>(fetch_sub(1)); }
__return_pointer_type
operator--(int) volatile
{ return reinterpret_cast<__return_pointer_type>(fetch_sub(1)); }
__return_pointer_type
operator++()
{ return reinterpret_cast<__return_pointer_type>(fetch_add(1) + 1); }
__return_pointer_type
operator++() volatile
{ return reinterpret_cast<__return_pointer_type>(fetch_add(1) + 1); }
__return_pointer_type
operator--()
{ return reinterpret_cast<__return_pointer_type>(fetch_sub(1) - 1); }
__return_pointer_type
operator--() volatile
{ return reinterpret_cast<__return_pointer_type>(fetch_sub(1) - 1); }
__return_pointer_type
operator+=(ptrdiff_t __d)
{ return reinterpret_cast<__return_pointer_type>(fetch_add(__d) + __d); }
__return_pointer_type
operator+=(ptrdiff_t __d) volatile
{ return reinterpret_cast<__return_pointer_type>(fetch_add(__d) + __d); }
__return_pointer_type
operator-=(ptrdiff_t __d)
{ return reinterpret_cast<__return_pointer_type>(fetch_sub(__d) - __d); }
__return_pointer_type
operator-=(ptrdiff_t __d) volatile
{ return reinterpret_cast<__return_pointer_type>(fetch_sub(__d) - __d); }
bool
is_lock_free() const
{ return true; }
bool
is_lock_free() const volatile
{ return true; }
void
store(__pointer_type __p, memory_order __m = memory_order_seq_cst)
{
__glibcxx_assert(__m != memory_order_acquire);
__glibcxx_assert(__m != memory_order_acq_rel);
__glibcxx_assert(__m != memory_order_consume);
_ATOMIC_STORE_(this, __p, __m);
}
void
store(__pointer_type __p,
memory_order __m = memory_order_seq_cst) volatile
{
__glibcxx_assert(__m != memory_order_acquire);
__glibcxx_assert(__m != memory_order_acq_rel);
__glibcxx_assert(__m != memory_order_consume);
volatile __pointer_type* __p2 = &_M_i;
__typeof__(__p) __w = (__p);
__atomic_flag_base* __g = __atomic_flag_for_address(__p2);
__atomic_flag_wait_explicit(__g, __m);
*__p2 = reinterpret_cast<__pointer_type>(__w);
atomic_flag_clear_explicit(__g, __m);
__w;
}
__return_pointer_type
load(memory_order __m = memory_order_seq_cst) const
{
__glibcxx_assert(__m != memory_order_release);
__glibcxx_assert(__m != memory_order_acq_rel);
void* __v = _ATOMIC_LOAD_(this, __m);
return reinterpret_cast<__return_pointer_type>(__v);
}
__return_pointer_type
load(memory_order __m = memory_order_seq_cst) const volatile
{
__glibcxx_assert(__m != memory_order_release);
__glibcxx_assert(__m != memory_order_acq_rel);
void* __v = _ATOMIC_LOAD_(this, __m);
return reinterpret_cast<__return_pointer_type>(__v);
}
__return_pointer_type
exchange(__pointer_type __p, memory_order __m = memory_order_seq_cst)
{
void* __v = _ATOMIC_MODIFY_(this, =, __p, __m);
return reinterpret_cast<__return_pointer_type>(__v);
}
__return_pointer_type
exchange(__pointer_type __p,
memory_order __m = memory_order_seq_cst) volatile
{
volatile __pointer_type* __p2 = &_M_i;
__typeof__(__p) __w = (__p);
__atomic_flag_base* __g = __atomic_flag_for_address(__p2);
__atomic_flag_wait_explicit(__g, __m);
__pointer_type __r = *__p2;
*__p2 = __w;
atomic_flag_clear_explicit(__g, __m);
__r;
return reinterpret_cast<__return_pointer_type>(_M_i);
}
bool
compare_exchange_strong(__return_pointer_type& __rp1, __pointer_type __p2,
memory_order __m1, memory_order __m2)
{
__glibcxx_assert(__m2 != memory_order_release);
__glibcxx_assert(__m2 != memory_order_acq_rel);
__glibcxx_assert(__m2 <= __m1);
__pointer_type& __p1 = reinterpret_cast<void*&>(__rp1);
return _ATOMIC_CMPEXCHNG_(this, &__p1, __p2, __m1);
}
bool
compare_exchange_strong(__return_pointer_type& __rp1, __pointer_type __p2,
memory_order __m1, memory_order __m2) volatile
{
__glibcxx_assert(__m2 != memory_order_release);
__glibcxx_assert(__m2 != memory_order_acq_rel);
__glibcxx_assert(__m2 <= __m1);
__pointer_type& __p1 = reinterpret_cast<void*&>(__rp1);
return _ATOMIC_CMPEXCHNG_(this, &__p1, __p2, __m1);
}
__return_pointer_type
fetch_add(ptrdiff_t __d, memory_order __m = memory_order_seq_cst)
{
void* __v = _ATOMIC_MODIFY_(this, +=, __d, __m);
return reinterpret_cast<__return_pointer_type>(__v);
}
__return_pointer_type
fetch_add(ptrdiff_t __d,
memory_order __m = memory_order_seq_cst) volatile
{
void* __v = _ATOMIC_MODIFY_(this, +=, __d, __m);
return reinterpret_cast<__return_pointer_type>(__v);
}
__return_pointer_type
fetch_sub(ptrdiff_t __d, memory_order __m = memory_order_seq_cst)
{
void* __v = _ATOMIC_MODIFY_(this, -=, __d, __m);
return reinterpret_cast<__return_pointer_type>(__v);
}
__return_pointer_type
fetch_sub(ptrdiff_t __d,
memory_order __m = memory_order_seq_cst) volatile
{
void* __v = _ATOMIC_MODIFY_(this, -=, __d, __m);
return reinterpret_cast<__return_pointer_type>(__v);
}
};
#undef _ATOMIC_LOAD_
#undef _ATOMIC_STORE_
#undef _ATOMIC_MODIFY_
#undef _ATOMIC_CMPEXCHNG_
} // namespace __atomic0
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace std
#endif
