llvm-project/libcxx/include/__memory/allocator.h

228 lines
7.5 KiB
C++

// -*- 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
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP___MEMORY_ALLOCATOR_H
#define _LIBCPP___MEMORY_ALLOCATOR_H
#include <__config>
#include <__memory/allocator_traits.h>
#include <cstddef>
#include <new>
#include <stdexcept>
#include <type_traits>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#pragma GCC system_header
#endif
_LIBCPP_PUSH_MACROS
#include <__undef_macros>
_LIBCPP_BEGIN_NAMESPACE_STD
template <class _Tp> class allocator;
#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_ALLOCATOR_MEMBERS)
template <>
class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX17 allocator<void>
{
public:
typedef void* pointer;
typedef const void* const_pointer;
typedef void value_type;
template <class _Up> struct rebind {typedef allocator<_Up> other;};
};
template <>
class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX17 allocator<const void>
{
public:
typedef const void* pointer;
typedef const void* const_pointer;
typedef const void value_type;
template <class _Up> struct rebind {typedef allocator<_Up> other;};
};
#endif
// allocator
template <class _Tp>
class _LIBCPP_TEMPLATE_VIS allocator
{
public:
typedef size_t size_type;
typedef ptrdiff_t difference_type;
typedef _Tp value_type;
typedef true_type propagate_on_container_move_assignment;
typedef true_type is_always_equal;
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
allocator() _NOEXCEPT { }
template <class _Up>
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
allocator(const allocator<_Up>&) _NOEXCEPT { }
_LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
_Tp* allocate(size_t __n) {
if (__n > allocator_traits<allocator>::max_size(*this))
__throw_length_error("allocator<T>::allocate(size_t n)"
" 'n' exceeds maximum supported size");
if (__libcpp_is_constant_evaluated()) {
return static_cast<_Tp*>(::operator new(__n * sizeof(_Tp)));
} else {
return static_cast<_Tp*>(_VSTD::__libcpp_allocate(__n * sizeof(_Tp), _LIBCPP_ALIGNOF(_Tp)));
}
}
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
void deallocate(_Tp* __p, size_t __n) _NOEXCEPT {
if (__libcpp_is_constant_evaluated()) {
::operator delete(__p);
} else {
_VSTD::__libcpp_deallocate((void*)__p, __n * sizeof(_Tp), _LIBCPP_ALIGNOF(_Tp));
}
}
// C++20 Removed members
#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_ALLOCATOR_MEMBERS)
_LIBCPP_DEPRECATED_IN_CXX17 typedef _Tp* pointer;
_LIBCPP_DEPRECATED_IN_CXX17 typedef const _Tp* const_pointer;
_LIBCPP_DEPRECATED_IN_CXX17 typedef _Tp& reference;
_LIBCPP_DEPRECATED_IN_CXX17 typedef const _Tp& const_reference;
template <class _Up>
struct _LIBCPP_DEPRECATED_IN_CXX17 rebind {
typedef allocator<_Up> other;
};
_LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_INLINE_VISIBILITY
pointer address(reference __x) const _NOEXCEPT {
return _VSTD::addressof(__x);
}
_LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_INLINE_VISIBILITY
const_pointer address(const_reference __x) const _NOEXCEPT {
return _VSTD::addressof(__x);
}
_LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY _LIBCPP_DEPRECATED_IN_CXX17
_Tp* allocate(size_t __n, const void*) {
return allocate(__n);
}
_LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_INLINE_VISIBILITY size_type max_size() const _NOEXCEPT {
return size_type(~0) / sizeof(_Tp);
}
template <class _Up, class... _Args>
_LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_INLINE_VISIBILITY
void construct(_Up* __p, _Args&&... __args) {
::new ((void*)__p) _Up(_VSTD::forward<_Args>(__args)...);
}
_LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_INLINE_VISIBILITY
void destroy(pointer __p) {
__p->~_Tp();
}
#endif
};
template <class _Tp>
class _LIBCPP_TEMPLATE_VIS allocator<const _Tp>
{
public:
typedef size_t size_type;
typedef ptrdiff_t difference_type;
typedef const _Tp value_type;
typedef true_type propagate_on_container_move_assignment;
typedef true_type is_always_equal;
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
allocator() _NOEXCEPT { }
template <class _Up>
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
allocator(const allocator<_Up>&) _NOEXCEPT { }
_LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
const _Tp* allocate(size_t __n) {
if (__n > allocator_traits<allocator>::max_size(*this))
__throw_length_error("allocator<const T>::allocate(size_t n)"
" 'n' exceeds maximum supported size");
if (__libcpp_is_constant_evaluated()) {
return static_cast<const _Tp*>(::operator new(__n * sizeof(_Tp)));
} else {
return static_cast<const _Tp*>(_VSTD::__libcpp_allocate(__n * sizeof(_Tp), _LIBCPP_ALIGNOF(_Tp)));
}
}
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
void deallocate(const _Tp* __p, size_t __n) {
if (__libcpp_is_constant_evaluated()) {
::operator delete(const_cast<_Tp*>(__p));
} else {
_VSTD::__libcpp_deallocate((void*) const_cast<_Tp *>(__p), __n * sizeof(_Tp), _LIBCPP_ALIGNOF(_Tp));
}
}
// C++20 Removed members
#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_ALLOCATOR_MEMBERS)
_LIBCPP_DEPRECATED_IN_CXX17 typedef const _Tp* pointer;
_LIBCPP_DEPRECATED_IN_CXX17 typedef const _Tp* const_pointer;
_LIBCPP_DEPRECATED_IN_CXX17 typedef const _Tp& reference;
_LIBCPP_DEPRECATED_IN_CXX17 typedef const _Tp& const_reference;
template <class _Up>
struct _LIBCPP_DEPRECATED_IN_CXX17 rebind {
typedef allocator<_Up> other;
};
_LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_INLINE_VISIBILITY
const_pointer address(const_reference __x) const _NOEXCEPT {
return _VSTD::addressof(__x);
}
_LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY _LIBCPP_DEPRECATED_IN_CXX17
const _Tp* allocate(size_t __n, const void*) {
return allocate(__n);
}
_LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_INLINE_VISIBILITY size_type max_size() const _NOEXCEPT {
return size_type(~0) / sizeof(_Tp);
}
template <class _Up, class... _Args>
_LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_INLINE_VISIBILITY
void construct(_Up* __p, _Args&&... __args) {
::new ((void*)__p) _Up(_VSTD::forward<_Args>(__args)...);
}
_LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_INLINE_VISIBILITY
void destroy(pointer __p) {
__p->~_Tp();
}
#endif
};
template <class _Tp, class _Up>
inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
bool operator==(const allocator<_Tp>&, const allocator<_Up>&) _NOEXCEPT {return true;}
template <class _Tp, class _Up>
inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
bool operator!=(const allocator<_Tp>&, const allocator<_Up>&) _NOEXCEPT {return false;}
_LIBCPP_END_NAMESPACE_STD
_LIBCPP_POP_MACROS
#endif // _LIBCPP___MEMORY_ALLOCATOR_H