libcxx/include/__split_buffer
2021-03-25 00:29:10 -07:00

645 lines
22 KiB
C++

// -*- C++ -*-
#ifndef _LIBCPP_SPLIT_BUFFER
#define _LIBCPP_SPLIT_BUFFER
#include <__config>
#include <type_traits>
#include <algorithm>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#pragma GCC system_header
#endif
_LIBCPP_PUSH_MACROS
#include <__undef_macros>
_LIBCPP_BEGIN_NAMESPACE_STD
template <bool>
class __split_buffer_common
{
protected:
void __throw_length_error() const;
void __throw_out_of_range() const;
};
template <class _Tp, class _Allocator = allocator<_Tp> >
struct __split_buffer
: private __split_buffer_common<true>
{
private:
__split_buffer(const __split_buffer&);
__split_buffer& operator=(const __split_buffer&);
public:
typedef _Tp value_type;
typedef _Allocator allocator_type;
typedef typename remove_reference<allocator_type>::type __alloc_rr;
typedef allocator_traits<__alloc_rr> __alloc_traits;
typedef value_type& reference;
typedef const value_type& const_reference;
typedef typename __alloc_traits::size_type size_type;
typedef typename __alloc_traits::difference_type difference_type;
typedef typename __alloc_traits::pointer pointer;
typedef typename __alloc_traits::const_pointer const_pointer;
typedef pointer iterator;
typedef const_pointer const_iterator;
pointer __first_;
pointer __begin_;
pointer __end_;
__compressed_pair<pointer, allocator_type> __end_cap_;
typedef typename add_lvalue_reference<allocator_type>::type __alloc_ref;
typedef typename add_lvalue_reference<allocator_type>::type __alloc_const_ref;
_LIBCPP_INLINE_VISIBILITY __alloc_rr& __alloc() _NOEXCEPT {return __end_cap_.second();}
_LIBCPP_INLINE_VISIBILITY const __alloc_rr& __alloc() const _NOEXCEPT {return __end_cap_.second();}
_LIBCPP_INLINE_VISIBILITY pointer& __end_cap() _NOEXCEPT {return __end_cap_.first();}
_LIBCPP_INLINE_VISIBILITY const pointer& __end_cap() const _NOEXCEPT {return __end_cap_.first();}
_LIBCPP_INLINE_VISIBILITY
__split_buffer()
_NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value);
_LIBCPP_INLINE_VISIBILITY
explicit __split_buffer(__alloc_rr& __a);
_LIBCPP_INLINE_VISIBILITY
explicit __split_buffer(const __alloc_rr& __a);
__split_buffer(size_type __cap, size_type __start, __alloc_rr& __a);
~__split_buffer();
#ifndef _LIBCPP_CXX03_LANG
__split_buffer(__split_buffer&& __c)
_NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value);
__split_buffer(__split_buffer&& __c, const __alloc_rr& __a);
__split_buffer& operator=(__split_buffer&& __c)
_NOEXCEPT_((__alloc_traits::propagate_on_container_move_assignment::value &&
is_nothrow_move_assignable<allocator_type>::value) ||
!__alloc_traits::propagate_on_container_move_assignment::value);
#endif // _LIBCPP_CXX03_LANG
_LIBCPP_INLINE_VISIBILITY iterator begin() _NOEXCEPT {return __begin_;}
_LIBCPP_INLINE_VISIBILITY const_iterator begin() const _NOEXCEPT {return __begin_;}
_LIBCPP_INLINE_VISIBILITY iterator end() _NOEXCEPT {return __end_;}
_LIBCPP_INLINE_VISIBILITY const_iterator end() const _NOEXCEPT {return __end_;}
_LIBCPP_INLINE_VISIBILITY
void clear() _NOEXCEPT
{__destruct_at_end(__begin_);}
_LIBCPP_INLINE_VISIBILITY size_type size() const {return static_cast<size_type>(__end_ - __begin_);}
_LIBCPP_INLINE_VISIBILITY bool empty() const {return __end_ == __begin_;}
_LIBCPP_INLINE_VISIBILITY size_type capacity() const {return static_cast<size_type>(__end_cap() - __first_);}
_LIBCPP_INLINE_VISIBILITY size_type __front_spare() const {return static_cast<size_type>(__begin_ - __first_);}
_LIBCPP_INLINE_VISIBILITY size_type __back_spare() const {return static_cast<size_type>(__end_cap() - __end_);}
_LIBCPP_INLINE_VISIBILITY reference front() {return *__begin_;}
_LIBCPP_INLINE_VISIBILITY const_reference front() const {return *__begin_;}
_LIBCPP_INLINE_VISIBILITY reference back() {return *(__end_ - 1);}
_LIBCPP_INLINE_VISIBILITY const_reference back() const {return *(__end_ - 1);}
void reserve(size_type __n);
void shrink_to_fit() _NOEXCEPT;
void push_front(const_reference __x);
_LIBCPP_INLINE_VISIBILITY void push_back(const_reference __x);
#ifndef _LIBCPP_CXX03_LANG
void push_front(value_type&& __x);
void push_back(value_type&& __x);
template <class... _Args>
void emplace_back(_Args&&... __args);
#endif // !defined(_LIBCPP_CXX03_LANG)
_LIBCPP_INLINE_VISIBILITY void pop_front() {__destruct_at_begin(__begin_+1);}
_LIBCPP_INLINE_VISIBILITY void pop_back() {__destruct_at_end(__end_-1);}
void __construct_at_end(size_type __n);
void __construct_at_end(size_type __n, const_reference __x);
template <class _InputIter>
typename enable_if
<
__is_cpp17_input_iterator<_InputIter>::value &&
!__is_cpp17_forward_iterator<_InputIter>::value,
void
>::type
__construct_at_end(_InputIter __first, _InputIter __last);
template <class _ForwardIterator>
typename enable_if
<
__is_cpp17_forward_iterator<_ForwardIterator>::value,
void
>::type
__construct_at_end(_ForwardIterator __first, _ForwardIterator __last);
_LIBCPP_INLINE_VISIBILITY void __destruct_at_begin(pointer __new_begin)
{__destruct_at_begin(__new_begin, is_trivially_destructible<value_type>());}
_LIBCPP_INLINE_VISIBILITY
void __destruct_at_begin(pointer __new_begin, false_type);
_LIBCPP_INLINE_VISIBILITY
void __destruct_at_begin(pointer __new_begin, true_type);
_LIBCPP_INLINE_VISIBILITY
void __destruct_at_end(pointer __new_last) _NOEXCEPT
{__destruct_at_end(__new_last, false_type());}
_LIBCPP_INLINE_VISIBILITY
void __destruct_at_end(pointer __new_last, false_type) _NOEXCEPT;
_LIBCPP_INLINE_VISIBILITY
void __destruct_at_end(pointer __new_last, true_type) _NOEXCEPT;
void swap(__split_buffer& __x)
_NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value||
__is_nothrow_swappable<__alloc_rr>::value);
bool __invariants() const;
private:
_LIBCPP_INLINE_VISIBILITY
void __move_assign_alloc(__split_buffer& __c, true_type)
_NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value)
{
__alloc() = _VSTD::move(__c.__alloc());
}
_LIBCPP_INLINE_VISIBILITY
void __move_assign_alloc(__split_buffer&, false_type) _NOEXCEPT
{}
struct _ConstructTransaction {
explicit _ConstructTransaction(pointer* __p, size_type __n) _NOEXCEPT
: __pos_(*__p), __end_(*__p + __n), __dest_(__p) {
}
~_ConstructTransaction() {
*__dest_ = __pos_;
}
pointer __pos_;
const pointer __end_;
private:
pointer *__dest_;
};
};
template <class _Tp, class _Allocator>
bool
__split_buffer<_Tp, _Allocator>::__invariants() const
{
if (__first_ == nullptr)
{
if (__begin_ != nullptr)
return false;
if (__end_ != nullptr)
return false;
if (__end_cap() != nullptr)
return false;
}
else
{
if (__begin_ < __first_)
return false;
if (__end_ < __begin_)
return false;
if (__end_cap() < __end_)
return false;
}
return true;
}
// Default constructs __n objects starting at __end_
// throws if construction throws
// Precondition: __n > 0
// Precondition: size() + __n <= capacity()
// Postcondition: size() == size() + __n
template <class _Tp, class _Allocator>
void
__split_buffer<_Tp, _Allocator>::__construct_at_end(size_type __n)
{
_ConstructTransaction __tx(&this->__end_, __n);
for (; __tx.__pos_ != __tx.__end_; ++__tx.__pos_) {
__alloc_traits::construct(this->__alloc(), _VSTD::__to_address(__tx.__pos_));
}
}
// Copy constructs __n objects starting at __end_ from __x
// throws if construction throws
// Precondition: __n > 0
// Precondition: size() + __n <= capacity()
// Postcondition: size() == old size() + __n
// Postcondition: [i] == __x for all i in [size() - __n, __n)
template <class _Tp, class _Allocator>
void
__split_buffer<_Tp, _Allocator>::__construct_at_end(size_type __n, const_reference __x)
{
_ConstructTransaction __tx(&this->__end_, __n);
for (; __tx.__pos_ != __tx.__end_; ++__tx.__pos_) {
__alloc_traits::construct(this->__alloc(),
_VSTD::__to_address(__tx.__pos_), __x);
}
}
template <class _Tp, class _Allocator>
template <class _InputIter>
typename enable_if
<
__is_cpp17_input_iterator<_InputIter>::value &&
!__is_cpp17_forward_iterator<_InputIter>::value,
void
>::type
__split_buffer<_Tp, _Allocator>::__construct_at_end(_InputIter __first, _InputIter __last)
{
__alloc_rr& __a = this->__alloc();
for (; __first != __last; ++__first)
{
if (__end_ == __end_cap())
{
size_type __old_cap = __end_cap() - __first_;
size_type __new_cap = _VSTD::max<size_type>(2 * __old_cap, 8);
__split_buffer __buf(__new_cap, 0, __a);
for (pointer __p = __begin_; __p != __end_; ++__p, ++__buf.__end_)
__alloc_traits::construct(__buf.__alloc(),
_VSTD::__to_address(__buf.__end_), _VSTD::move(*__p));
swap(__buf);
}
__alloc_traits::construct(__a, _VSTD::__to_address(this->__end_), *__first);
++this->__end_;
}
}
template <class _Tp, class _Allocator>
template <class _ForwardIterator>
typename enable_if
<
__is_cpp17_forward_iterator<_ForwardIterator>::value,
void
>::type
__split_buffer<_Tp, _Allocator>::__construct_at_end(_ForwardIterator __first, _ForwardIterator __last)
{
_ConstructTransaction __tx(&this->__end_, std::distance(__first, __last));
for (; __tx.__pos_ != __tx.__end_; ++__tx.__pos_, ++__first) {
__alloc_traits::construct(this->__alloc(),
_VSTD::__to_address(__tx.__pos_), *__first);
}
}
template <class _Tp, class _Allocator>
inline
void
__split_buffer<_Tp, _Allocator>::__destruct_at_begin(pointer __new_begin, false_type)
{
while (__begin_ != __new_begin)
__alloc_traits::destroy(__alloc(), __to_address(__begin_++));
}
template <class _Tp, class _Allocator>
inline
void
__split_buffer<_Tp, _Allocator>::__destruct_at_begin(pointer __new_begin, true_type)
{
__begin_ = __new_begin;
}
template <class _Tp, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
void
__split_buffer<_Tp, _Allocator>::__destruct_at_end(pointer __new_last, false_type) _NOEXCEPT
{
while (__new_last != __end_)
__alloc_traits::destroy(__alloc(), __to_address(--__end_));
}
template <class _Tp, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
void
__split_buffer<_Tp, _Allocator>::__destruct_at_end(pointer __new_last, true_type) _NOEXCEPT
{
__end_ = __new_last;
}
template <class _Tp, class _Allocator>
__split_buffer<_Tp, _Allocator>::__split_buffer(size_type __cap, size_type __start, __alloc_rr& __a)
: __end_cap_(nullptr, __a)
{
__first_ = __cap != 0 ? __alloc_traits::allocate(__alloc(), __cap) : nullptr;
__begin_ = __end_ = __first_ + __start;
__end_cap() = __first_ + __cap;
}
template <class _Tp, class _Allocator>
inline
__split_buffer<_Tp, _Allocator>::__split_buffer()
_NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value)
: __first_(nullptr), __begin_(nullptr), __end_(nullptr), __end_cap_(nullptr, __default_init_tag())
{
}
template <class _Tp, class _Allocator>
inline
__split_buffer<_Tp, _Allocator>::__split_buffer(__alloc_rr& __a)
: __first_(nullptr), __begin_(nullptr), __end_(nullptr), __end_cap_(nullptr, __a)
{
}
template <class _Tp, class _Allocator>
inline
__split_buffer<_Tp, _Allocator>::__split_buffer(const __alloc_rr& __a)
: __first_(nullptr), __begin_(nullptr), __end_(nullptr), __end_cap_(nullptr, __a)
{
}
template <class _Tp, class _Allocator>
__split_buffer<_Tp, _Allocator>::~__split_buffer()
{
clear();
if (__first_)
__alloc_traits::deallocate(__alloc(), __first_, capacity());
}
#ifndef _LIBCPP_CXX03_LANG
template <class _Tp, class _Allocator>
__split_buffer<_Tp, _Allocator>::__split_buffer(__split_buffer&& __c)
_NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value)
: __first_(_VSTD::move(__c.__first_)),
__begin_(_VSTD::move(__c.__begin_)),
__end_(_VSTD::move(__c.__end_)),
__end_cap_(_VSTD::move(__c.__end_cap_))
{
__c.__first_ = nullptr;
__c.__begin_ = nullptr;
__c.__end_ = nullptr;
__c.__end_cap() = nullptr;
}
template <class _Tp, class _Allocator>
__split_buffer<_Tp, _Allocator>::__split_buffer(__split_buffer&& __c, const __alloc_rr& __a)
: __end_cap_(nullptr, __a)
{
if (__a == __c.__alloc())
{
__first_ = __c.__first_;
__begin_ = __c.__begin_;
__end_ = __c.__end_;
__end_cap() = __c.__end_cap();
__c.__first_ = nullptr;
__c.__begin_ = nullptr;
__c.__end_ = nullptr;
__c.__end_cap() = nullptr;
}
else
{
size_type __cap = __c.size();
__first_ = __alloc_traits::allocate(__alloc(), __cap);
__begin_ = __end_ = __first_;
__end_cap() = __first_ + __cap;
typedef move_iterator<iterator> _Ip;
__construct_at_end(_Ip(__c.begin()), _Ip(__c.end()));
}
}
template <class _Tp, class _Allocator>
__split_buffer<_Tp, _Allocator>&
__split_buffer<_Tp, _Allocator>::operator=(__split_buffer&& __c)
_NOEXCEPT_((__alloc_traits::propagate_on_container_move_assignment::value &&
is_nothrow_move_assignable<allocator_type>::value) ||
!__alloc_traits::propagate_on_container_move_assignment::value)
{
clear();
shrink_to_fit();
__first_ = __c.__first_;
__begin_ = __c.__begin_;
__end_ = __c.__end_;
__end_cap() = __c.__end_cap();
__move_assign_alloc(__c,
integral_constant<bool,
__alloc_traits::propagate_on_container_move_assignment::value>());
__c.__first_ = __c.__begin_ = __c.__end_ = __c.__end_cap() = nullptr;
return *this;
}
#endif // _LIBCPP_CXX03_LANG
template <class _Tp, class _Allocator>
void
__split_buffer<_Tp, _Allocator>::swap(__split_buffer& __x)
_NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value||
__is_nothrow_swappable<__alloc_rr>::value)
{
_VSTD::swap(__first_, __x.__first_);
_VSTD::swap(__begin_, __x.__begin_);
_VSTD::swap(__end_, __x.__end_);
_VSTD::swap(__end_cap(), __x.__end_cap());
__swap_allocator(__alloc(), __x.__alloc());
}
template <class _Tp, class _Allocator>
void
__split_buffer<_Tp, _Allocator>::reserve(size_type __n)
{
if (__n < capacity())
{
__split_buffer<value_type, __alloc_rr&> __t(__n, 0, __alloc());
__t.__construct_at_end(move_iterator<pointer>(__begin_),
move_iterator<pointer>(__end_));
_VSTD::swap(__first_, __t.__first_);
_VSTD::swap(__begin_, __t.__begin_);
_VSTD::swap(__end_, __t.__end_);
_VSTD::swap(__end_cap(), __t.__end_cap());
}
}
template <class _Tp, class _Allocator>
void
__split_buffer<_Tp, _Allocator>::shrink_to_fit() _NOEXCEPT
{
if (capacity() > size())
{
#ifndef _LIBCPP_NO_EXCEPTIONS
try
{
#endif // _LIBCPP_NO_EXCEPTIONS
__split_buffer<value_type, __alloc_rr&> __t(size(), 0, __alloc());
__t.__construct_at_end(move_iterator<pointer>(__begin_),
move_iterator<pointer>(__end_));
__t.__end_ = __t.__begin_ + (__end_ - __begin_);
_VSTD::swap(__first_, __t.__first_);
_VSTD::swap(__begin_, __t.__begin_);
_VSTD::swap(__end_, __t.__end_);
_VSTD::swap(__end_cap(), __t.__end_cap());
#ifndef _LIBCPP_NO_EXCEPTIONS
}
catch (...)
{
}
#endif // _LIBCPP_NO_EXCEPTIONS
}
}
template <class _Tp, class _Allocator>
void
__split_buffer<_Tp, _Allocator>::push_front(const_reference __x)
{
if (__begin_ == __first_)
{
if (__end_ < __end_cap())
{
difference_type __d = __end_cap() - __end_;
__d = (__d + 1) / 2;
__begin_ = _VSTD::move_backward(__begin_, __end_, __end_ + __d);
__end_ += __d;
}
else
{
size_type __c = max<size_type>(2 * static_cast<size_t>(__end_cap() - __first_), 1);
__split_buffer<value_type, __alloc_rr&> __t(__c, (__c + 3) / 4, __alloc());
__t.__construct_at_end(move_iterator<pointer>(__begin_),
move_iterator<pointer>(__end_));
_VSTD::swap(__first_, __t.__first_);
_VSTD::swap(__begin_, __t.__begin_);
_VSTD::swap(__end_, __t.__end_);
_VSTD::swap(__end_cap(), __t.__end_cap());
}
}
__alloc_traits::construct(__alloc(), _VSTD::__to_address(__begin_-1), __x);
--__begin_;
}
#ifndef _LIBCPP_CXX03_LANG
template <class _Tp, class _Allocator>
void
__split_buffer<_Tp, _Allocator>::push_front(value_type&& __x)
{
if (__begin_ == __first_)
{
if (__end_ < __end_cap())
{
difference_type __d = __end_cap() - __end_;
__d = (__d + 1) / 2;
__begin_ = _VSTD::move_backward(__begin_, __end_, __end_ + __d);
__end_ += __d;
}
else
{
size_type __c = max<size_type>(2 * static_cast<size_t>(__end_cap() - __first_), 1);
__split_buffer<value_type, __alloc_rr&> __t(__c, (__c + 3) / 4, __alloc());
__t.__construct_at_end(move_iterator<pointer>(__begin_),
move_iterator<pointer>(__end_));
_VSTD::swap(__first_, __t.__first_);
_VSTD::swap(__begin_, __t.__begin_);
_VSTD::swap(__end_, __t.__end_);
_VSTD::swap(__end_cap(), __t.__end_cap());
}
}
__alloc_traits::construct(__alloc(), _VSTD::__to_address(__begin_-1),
_VSTD::move(__x));
--__begin_;
}
#endif // _LIBCPP_CXX03_LANG
template <class _Tp, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
void
__split_buffer<_Tp, _Allocator>::push_back(const_reference __x)
{
if (__end_ == __end_cap())
{
if (__begin_ > __first_)
{
difference_type __d = __begin_ - __first_;
__d = (__d + 1) / 2;
__end_ = _VSTD::move(__begin_, __end_, __begin_ - __d);
__begin_ -= __d;
}
else
{
size_type __c = max<size_type>(2 * static_cast<size_t>(__end_cap() - __first_), 1);
__split_buffer<value_type, __alloc_rr&> __t(__c, __c / 4, __alloc());
__t.__construct_at_end(move_iterator<pointer>(__begin_),
move_iterator<pointer>(__end_));
_VSTD::swap(__first_, __t.__first_);
_VSTD::swap(__begin_, __t.__begin_);
_VSTD::swap(__end_, __t.__end_);
_VSTD::swap(__end_cap(), __t.__end_cap());
}
}
__alloc_traits::construct(__alloc(), _VSTD::__to_address(__end_), __x);
++__end_;
}
#ifndef _LIBCPP_CXX03_LANG
template <class _Tp, class _Allocator>
void
__split_buffer<_Tp, _Allocator>::push_back(value_type&& __x)
{
if (__end_ == __end_cap())
{
if (__begin_ > __first_)
{
difference_type __d = __begin_ - __first_;
__d = (__d + 1) / 2;
__end_ = _VSTD::move(__begin_, __end_, __begin_ - __d);
__begin_ -= __d;
}
else
{
size_type __c = max<size_type>(2 * static_cast<size_t>(__end_cap() - __first_), 1);
__split_buffer<value_type, __alloc_rr&> __t(__c, __c / 4, __alloc());
__t.__construct_at_end(move_iterator<pointer>(__begin_),
move_iterator<pointer>(__end_));
_VSTD::swap(__first_, __t.__first_);
_VSTD::swap(__begin_, __t.__begin_);
_VSTD::swap(__end_, __t.__end_);
_VSTD::swap(__end_cap(), __t.__end_cap());
}
}
__alloc_traits::construct(__alloc(), _VSTD::__to_address(__end_),
_VSTD::move(__x));
++__end_;
}
template <class _Tp, class _Allocator>
template <class... _Args>
void
__split_buffer<_Tp, _Allocator>::emplace_back(_Args&&... __args)
{
if (__end_ == __end_cap())
{
if (__begin_ > __first_)
{
difference_type __d = __begin_ - __first_;
__d = (__d + 1) / 2;
__end_ = _VSTD::move(__begin_, __end_, __begin_ - __d);
__begin_ -= __d;
}
else
{
size_type __c = max<size_type>(2 * static_cast<size_t>(__end_cap() - __first_), 1);
__split_buffer<value_type, __alloc_rr&> __t(__c, __c / 4, __alloc());
__t.__construct_at_end(move_iterator<pointer>(__begin_),
move_iterator<pointer>(__end_));
_VSTD::swap(__first_, __t.__first_);
_VSTD::swap(__begin_, __t.__begin_);
_VSTD::swap(__end_, __t.__end_);
_VSTD::swap(__end_cap(), __t.__end_cap());
}
}
__alloc_traits::construct(__alloc(), _VSTD::__to_address(__end_),
_VSTD::forward<_Args>(__args)...);
++__end_;
}
#endif // _LIBCPP_CXX03_LANG
template <class _Tp, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
void
swap(__split_buffer<_Tp, _Allocator>& __x, __split_buffer<_Tp, _Allocator>& __y)
_NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
{
__x.swap(__y);
}
_LIBCPP_END_NAMESPACE_STD
_LIBCPP_POP_MACROS
#endif // _LIBCPP_SPLIT_BUFFER