diff options
Diffstat (limited to 'contrib/llvm-project/libcxx/include/span')
| -rw-r--r-- | contrib/llvm-project/libcxx/include/span | 701 |
1 files changed, 330 insertions, 371 deletions
diff --git a/contrib/llvm-project/libcxx/include/span b/contrib/llvm-project/libcxx/include/span index f94bda40fa73..7dd53110ac29 100644 --- a/contrib/llvm-project/libcxx/include/span +++ b/contrib/llvm-project/libcxx/include/span @@ -144,8 +144,8 @@ template<class R> #include <__type_traits/remove_reference.h> #include <__type_traits/type_identity.h> #include <__utility/forward.h> -#include <array> // for array -#include <cstddef> // for byte +#include <array> // for array +#include <cstddef> // for byte #include <version> // standard-mandated includes @@ -182,19 +182,20 @@ struct __is_std_span<span<_Tp, _Sz>> : true_type {}; template <class _Range, class _ElementType> concept __span_compatible_range = - ranges::contiguous_range<_Range> && // - ranges::sized_range<_Range> && // - (ranges::borrowed_range<_Range> || is_const_v<_ElementType>) && // - !__is_std_span<remove_cvref_t<_Range>>::value && // - !__is_std_array<remove_cvref_t<_Range>>::value && // - !is_array_v<remove_cvref_t<_Range>> && // - is_convertible_v<remove_reference_t<ranges::range_reference_t<_Range>>(*)[], _ElementType(*)[]>; + ranges::contiguous_range<_Range> && // + ranges::sized_range<_Range> && // + (ranges::borrowed_range<_Range> || is_const_v<_ElementType>)&& // + !__is_std_span<remove_cvref_t<_Range>>::value && // + !__is_std_array<remove_cvref_t<_Range>>::value && // + !is_array_v<remove_cvref_t<_Range>> && // + is_convertible_v<remove_reference_t<ranges::range_reference_t<_Range>> (*)[], _ElementType (*)[]>; template <class _From, class _To> -concept __span_array_convertible = is_convertible_v<_From(*)[], _To(*)[]>; +concept __span_array_convertible = is_convertible_v<_From (*)[], _To (*)[]>; template <class _It, class _Tp> -concept __span_compatible_iterator = contiguous_iterator<_It> && __span_array_convertible<remove_reference_t<iter_reference_t<_It>>, _Tp>; +concept __span_compatible_iterator = + contiguous_iterator<_It> && __span_array_convertible<remove_reference_t<iter_reference_t<_It>>, _Tp>; template <class _Sentinel, class _It> concept __span_compatible_sentinel_for = sized_sentinel_for<_Sentinel, _It> && !is_convertible_v<_Sentinel, size_t>; @@ -202,356 +203,313 @@ concept __span_compatible_sentinel_for = sized_sentinel_for<_Sentinel, _It> && ! template <typename _Tp, size_t _Extent> class _LIBCPP_TEMPLATE_VIS span { public: -// constants and types - using element_type = _Tp; - using value_type = remove_cv_t<_Tp>; - using size_type = size_t; - using difference_type = ptrdiff_t; - using pointer = _Tp *; - using const_pointer = const _Tp *; - using reference = _Tp &; - using const_reference = const _Tp &; -#ifdef _LIBCPP_ABI_BOUNDED_ITERATORS - using iterator = __bounded_iter<pointer>; -#else - using iterator = __wrap_iter<pointer>; -#endif - using reverse_iterator = std::reverse_iterator<iterator>; - - static constexpr size_type extent = _Extent; - -// [span.cons], span constructors, copy, assignment, and destructor - template <size_t _Sz = _Extent> requires(_Sz == 0) - _LIBCPP_HIDE_FROM_ABI constexpr span() noexcept : __data_{nullptr} {} - - constexpr span (const span&) noexcept = default; - constexpr span& operator=(const span&) noexcept = default; - - template <__span_compatible_iterator<element_type> _It> - _LIBCPP_HIDE_FROM_ABI - constexpr explicit span(_It __first, size_type __count) - : __data_{std::to_address(__first)} { - (void)__count; - _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(_Extent == __count, "size mismatch in span's constructor (iterator, len)"); - } - - template <__span_compatible_iterator<element_type> _It, __span_compatible_sentinel_for<_It> _End> - _LIBCPP_HIDE_FROM_ABI - constexpr explicit span(_It __first, _End __last) : __data_{std::to_address(__first)} { - // [span.cons]/10 - // Throws: When and what last - first throws. - [[maybe_unused]] auto __dist = __last - __first; - _LIBCPP_ASSERT_VALID_INPUT_RANGE(__dist >= 0, "invalid range in span's constructor (iterator, sentinel)"); - _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS( - __dist == _Extent, "invalid range in span's constructor (iterator, sentinel): last - first != extent"); - } - - _LIBCPP_HIDE_FROM_ABI constexpr span(type_identity_t<element_type> (&__arr)[_Extent]) noexcept : __data_{__arr} {} - - template <__span_array_convertible<element_type> _OtherElementType> - _LIBCPP_HIDE_FROM_ABI - constexpr span(array<_OtherElementType, _Extent>& __arr) noexcept : __data_{__arr.data()} {} - - template <class _OtherElementType> - requires __span_array_convertible<const _OtherElementType, element_type> - _LIBCPP_HIDE_FROM_ABI - constexpr span(const array<_OtherElementType, _Extent>& __arr) noexcept : __data_{__arr.data()} {} - - template <__span_compatible_range<element_type> _Range> - _LIBCPP_HIDE_FROM_ABI - constexpr explicit span(_Range&& __r) : __data_{ranges::data(__r)} { - _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS( - ranges::size(__r) == _Extent, "size mismatch in span's constructor (range)"); - } - - template <__span_array_convertible<element_type> _OtherElementType> - _LIBCPP_HIDE_FROM_ABI - constexpr span(const span<_OtherElementType, _Extent>& __other) - : __data_{__other.data()} {} - - template <__span_array_convertible<element_type> _OtherElementType> - _LIBCPP_HIDE_FROM_ABI - constexpr explicit span(const span<_OtherElementType, dynamic_extent>& __other) noexcept - : __data_{__other.data()} { - _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS( - _Extent == __other.size(), "size mismatch in span's constructor (other span)"); - } - - template <size_t _Count> - _LIBCPP_HIDE_FROM_ABI - constexpr span<element_type, _Count> first() const noexcept - { - static_assert(_Count <= _Extent, "span<T, N>::first<Count>(): Count out of range"); - return span<element_type, _Count>{data(), _Count}; - } - - template <size_t _Count> - _LIBCPP_HIDE_FROM_ABI - constexpr span<element_type, _Count> last() const noexcept - { - static_assert(_Count <= _Extent, "span<T, N>::last<Count>(): Count out of range"); - return span<element_type, _Count>{data() + size() - _Count, _Count}; - } - - _LIBCPP_HIDE_FROM_ABI - constexpr span<element_type, dynamic_extent> first(size_type __count) const noexcept - { - _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__count <= size(), "span<T, N>::first(count): count out of range"); - return {data(), __count}; - } - - _LIBCPP_HIDE_FROM_ABI - constexpr span<element_type, dynamic_extent> last(size_type __count) const noexcept - { - _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__count <= size(), "span<T, N>::last(count): count out of range"); - return {data() + size() - __count, __count}; - } - - template <size_t _Offset, size_t _Count = dynamic_extent> - _LIBCPP_HIDE_FROM_ABI - constexpr auto subspan() const noexcept - -> span<element_type, _Count != dynamic_extent ? _Count : _Extent - _Offset> - { - static_assert(_Offset <= _Extent, "span<T, N>::subspan<Offset, Count>(): Offset out of range"); - static_assert(_Count == dynamic_extent || _Count <= _Extent - _Offset, "span<T, N>::subspan<Offset, Count>(): Offset + Count out of range"); - - using _ReturnType = span<element_type, _Count != dynamic_extent ? _Count : _Extent - _Offset>; - return _ReturnType{data() + _Offset, _Count == dynamic_extent ? size() - _Offset : _Count}; - } - - - _LIBCPP_HIDE_FROM_ABI - constexpr span<element_type, dynamic_extent> - subspan(size_type __offset, size_type __count = dynamic_extent) const noexcept - { - _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS( - __offset <= size(), "span<T, N>::subspan(offset, count): offset out of range"); - if (__count == dynamic_extent) - return {data() + __offset, size() - __offset}; - _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS( - __count <= size() - __offset, "span<T, N>::subspan(offset, count): offset + count out of range"); - return {data() + __offset, __count}; - } - - _LIBCPP_HIDE_FROM_ABI constexpr size_type size() const noexcept { return _Extent; } - _LIBCPP_HIDE_FROM_ABI constexpr size_type size_bytes() const noexcept { return _Extent * sizeof(element_type); } - [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool empty() const noexcept { return _Extent == 0; } - - _LIBCPP_HIDE_FROM_ABI constexpr reference operator[](size_type __idx) const noexcept - { - _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__idx < size(), "span<T, N>::operator[](index): index out of range"); - return __data_[__idx]; - } - - _LIBCPP_HIDE_FROM_ABI constexpr reference front() const noexcept - { - _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "span<T, N>::front() on empty span"); - return __data_[0]; - } - - _LIBCPP_HIDE_FROM_ABI constexpr reference back() const noexcept - { - _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "span<T, N>::back() on empty span"); - return __data_[size()-1]; - } - - _LIBCPP_HIDE_FROM_ABI constexpr pointer data() const noexcept { return __data_; } - -// [span.iter], span iterator support - _LIBCPP_HIDE_FROM_ABI constexpr iterator begin() const noexcept { -#ifdef _LIBCPP_ABI_BOUNDED_ITERATORS - return std::__make_bounded_iter(data(), data(), data() + size()); -#else - return iterator(data()); -#endif - } - _LIBCPP_HIDE_FROM_ABI constexpr iterator end() const noexcept { -#ifdef _LIBCPP_ABI_BOUNDED_ITERATORS - return std::__make_bounded_iter(data() + size(), data(), data() + size()); -#else - return iterator(data() + size()); -#endif - } - _LIBCPP_HIDE_FROM_ABI constexpr reverse_iterator rbegin() const noexcept { return reverse_iterator(end()); } - _LIBCPP_HIDE_FROM_ABI constexpr reverse_iterator rend() const noexcept { return reverse_iterator(begin()); } - - _LIBCPP_HIDE_FROM_ABI span<const byte, _Extent * sizeof(element_type)> __as_bytes() const noexcept - { return span<const byte, _Extent * sizeof(element_type)>{reinterpret_cast<const byte *>(data()), size_bytes()}; } - - _LIBCPP_HIDE_FROM_ABI span<byte, _Extent * sizeof(element_type)> __as_writable_bytes() const noexcept - { return span<byte, _Extent * sizeof(element_type)>{reinterpret_cast<byte *>(data()), size_bytes()}; } + // constants and types + using element_type = _Tp; + using value_type = remove_cv_t<_Tp>; + using size_type = size_t; + using difference_type = ptrdiff_t; + using pointer = _Tp*; + using const_pointer = const _Tp*; + using reference = _Tp&; + using const_reference = const _Tp&; +# ifdef _LIBCPP_ABI_BOUNDED_ITERATORS + using iterator = __bounded_iter<pointer>; +# else + using iterator = __wrap_iter<pointer>; +# endif + using reverse_iterator = std::reverse_iterator<iterator>; + + static constexpr size_type extent = _Extent; + + // [span.cons], span constructors, copy, assignment, and destructor + template <size_t _Sz = _Extent> + requires(_Sz == 0) + _LIBCPP_HIDE_FROM_ABI constexpr span() noexcept : __data_{nullptr} {} + + constexpr span(const span&) noexcept = default; + constexpr span& operator=(const span&) noexcept = default; + + template <__span_compatible_iterator<element_type> _It> + _LIBCPP_HIDE_FROM_ABI constexpr explicit span(_It __first, size_type __count) : __data_{std::to_address(__first)} { + (void)__count; + _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(_Extent == __count, "size mismatch in span's constructor (iterator, len)"); + } + + template <__span_compatible_iterator<element_type> _It, __span_compatible_sentinel_for<_It> _End> + _LIBCPP_HIDE_FROM_ABI constexpr explicit span(_It __first, _End __last) : __data_{std::to_address(__first)} { + // [span.cons]/10 + // Throws: When and what last - first throws. + [[maybe_unused]] auto __dist = __last - __first; + _LIBCPP_ASSERT_VALID_INPUT_RANGE(__dist >= 0, "invalid range in span's constructor (iterator, sentinel)"); + _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS( + __dist == _Extent, "invalid range in span's constructor (iterator, sentinel): last - first != extent"); + } + + _LIBCPP_HIDE_FROM_ABI constexpr span(type_identity_t<element_type> (&__arr)[_Extent]) noexcept : __data_{__arr} {} + + template <__span_array_convertible<element_type> _OtherElementType> + _LIBCPP_HIDE_FROM_ABI constexpr span(array<_OtherElementType, _Extent>& __arr) noexcept : __data_{__arr.data()} {} + + template <class _OtherElementType> + requires __span_array_convertible<const _OtherElementType, element_type> + _LIBCPP_HIDE_FROM_ABI constexpr span(const array<_OtherElementType, _Extent>& __arr) noexcept + : __data_{__arr.data()} {} + + template <__span_compatible_range<element_type> _Range> + _LIBCPP_HIDE_FROM_ABI constexpr explicit span(_Range&& __r) : __data_{ranges::data(__r)} { + _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(ranges::size(__r) == _Extent, "size mismatch in span's constructor (range)"); + } + + template <__span_array_convertible<element_type> _OtherElementType> + _LIBCPP_HIDE_FROM_ABI constexpr span(const span<_OtherElementType, _Extent>& __other) : __data_{__other.data()} {} + + template <__span_array_convertible<element_type> _OtherElementType> + _LIBCPP_HIDE_FROM_ABI constexpr explicit span(const span<_OtherElementType, dynamic_extent>& __other) noexcept + : __data_{__other.data()} { + _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(_Extent == __other.size(), "size mismatch in span's constructor (other span)"); + } + + template <size_t _Count> + _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, _Count> first() const noexcept { + static_assert(_Count <= _Extent, "span<T, N>::first<Count>(): Count out of range"); + return span<element_type, _Count>{data(), _Count}; + } + + template <size_t _Count> + _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, _Count> last() const noexcept { + static_assert(_Count <= _Extent, "span<T, N>::last<Count>(): Count out of range"); + return span<element_type, _Count>{data() + size() - _Count, _Count}; + } + + _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, dynamic_extent> first(size_type __count) const noexcept { + _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__count <= size(), "span<T, N>::first(count): count out of range"); + return {data(), __count}; + } + + _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, dynamic_extent> last(size_type __count) const noexcept { + _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__count <= size(), "span<T, N>::last(count): count out of range"); + return {data() + size() - __count, __count}; + } + + template <size_t _Offset, size_t _Count = dynamic_extent> + _LIBCPP_HIDE_FROM_ABI constexpr auto subspan() const noexcept + -> span<element_type, _Count != dynamic_extent ? _Count : _Extent - _Offset> { + static_assert(_Offset <= _Extent, "span<T, N>::subspan<Offset, Count>(): Offset out of range"); + static_assert(_Count == dynamic_extent || _Count <= _Extent - _Offset, + "span<T, N>::subspan<Offset, Count>(): Offset + Count out of range"); + + using _ReturnType = span<element_type, _Count != dynamic_extent ? _Count : _Extent - _Offset>; + return _ReturnType{data() + _Offset, _Count == dynamic_extent ? size() - _Offset : _Count}; + } + + _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, dynamic_extent> + subspan(size_type __offset, size_type __count = dynamic_extent) const noexcept { + _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__offset <= size(), "span<T, N>::subspan(offset, count): offset out of range"); + if (__count == dynamic_extent) + return {data() + __offset, size() - __offset}; + _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS( + __count <= size() - __offset, "span<T, N>::subspan(offset, count): offset + count out of range"); + return {data() + __offset, __count}; + } + + _LIBCPP_HIDE_FROM_ABI constexpr size_type size() const noexcept { return _Extent; } + _LIBCPP_HIDE_FROM_ABI constexpr size_type size_bytes() const noexcept { return _Extent * sizeof(element_type); } + [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool empty() const noexcept { return _Extent == 0; } + + _LIBCPP_HIDE_FROM_ABI constexpr reference operator[](size_type __idx) const noexcept { + _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__idx < size(), "span<T, N>::operator[](index): index out of range"); + return __data_[__idx]; + } + + _LIBCPP_HIDE_FROM_ABI constexpr reference front() const noexcept { + _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "span<T, N>::front() on empty span"); + return __data_[0]; + } + + _LIBCPP_HIDE_FROM_ABI constexpr reference back() const noexcept { + _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "span<T, N>::back() on empty span"); + return __data_[size() - 1]; + } + + _LIBCPP_HIDE_FROM_ABI constexpr pointer data() const noexcept { return __data_; } + + // [span.iter], span iterator support + _LIBCPP_HIDE_FROM_ABI constexpr iterator begin() const noexcept { +# ifdef _LIBCPP_ABI_BOUNDED_ITERATORS + return std::__make_bounded_iter(data(), data(), data() + size()); +# else + return iterator(data()); +# endif + } + _LIBCPP_HIDE_FROM_ABI constexpr iterator end() const noexcept { +# ifdef _LIBCPP_ABI_BOUNDED_ITERATORS + return std::__make_bounded_iter(data() + size(), data(), data() + size()); +# else + return iterator(data() + size()); +# endif + } + _LIBCPP_HIDE_FROM_ABI constexpr reverse_iterator rbegin() const noexcept { return reverse_iterator(end()); } + _LIBCPP_HIDE_FROM_ABI constexpr reverse_iterator rend() const noexcept { return reverse_iterator(begin()); } + + _LIBCPP_HIDE_FROM_ABI span<const byte, _Extent * sizeof(element_type)> __as_bytes() const noexcept { + return span<const byte, _Extent * sizeof(element_type)>{reinterpret_cast<const byte*>(data()), size_bytes()}; + } + + _LIBCPP_HIDE_FROM_ABI span<byte, _Extent * sizeof(element_type)> __as_writable_bytes() const noexcept { + return span<byte, _Extent * sizeof(element_type)>{reinterpret_cast<byte*>(data()), size_bytes()}; + } private: - pointer __data_; + pointer __data_; }; - template <typename _Tp> class _LIBCPP_TEMPLATE_VIS span<_Tp, dynamic_extent> { public: -// constants and types - using element_type = _Tp; - using value_type = remove_cv_t<_Tp>; - using size_type = size_t; - using difference_type = ptrdiff_t; - using pointer = _Tp *; - using const_pointer = const _Tp *; - using reference = _Tp &; - using const_reference = const _Tp &; -#ifdef _LIBCPP_ABI_BOUNDED_ITERATORS - using iterator = __bounded_iter<pointer>; -#else - using iterator = __wrap_iter<pointer>; -#endif - using reverse_iterator = std::reverse_iterator<iterator>; - - static constexpr size_type extent = dynamic_extent; - -// [span.cons], span constructors, copy, assignment, and destructor - _LIBCPP_HIDE_FROM_ABI constexpr span() noexcept : __data_{nullptr}, __size_{0} {} - - constexpr span (const span&) noexcept = default; - constexpr span& operator=(const span&) noexcept = default; - - template <__span_compatible_iterator<element_type> _It> - _LIBCPP_HIDE_FROM_ABI - constexpr span(_It __first, size_type __count) - : __data_{std::to_address(__first)}, __size_{__count} {} - - template <__span_compatible_iterator<element_type> _It, __span_compatible_sentinel_for<_It> _End> - _LIBCPP_HIDE_FROM_ABI constexpr span(_It __first, _End __last) - : __data_(std::to_address(__first)), __size_(__last - __first) { - _LIBCPP_ASSERT_VALID_INPUT_RANGE( - __last - __first >= 0, "invalid range in span's constructor (iterator, sentinel)"); - } - - template <size_t _Sz> - _LIBCPP_HIDE_FROM_ABI - constexpr span(type_identity_t<element_type> (&__arr)[_Sz]) noexcept : __data_{__arr}, __size_{_Sz} {} - - template <__span_array_convertible<element_type> _OtherElementType, size_t _Sz> - _LIBCPP_HIDE_FROM_ABI - constexpr span(array<_OtherElementType, _Sz>& __arr) noexcept : __data_{__arr.data()}, __size_{_Sz} {} - - template <class _OtherElementType, size_t _Sz> - requires __span_array_convertible<const _OtherElementType, element_type> - _LIBCPP_HIDE_FROM_ABI - constexpr span(const array<_OtherElementType, _Sz>& __arr) noexcept : __data_{__arr.data()}, __size_{_Sz} {} - - template <__span_compatible_range<element_type> _Range> - _LIBCPP_HIDE_FROM_ABI - constexpr span(_Range&& __r) : __data_(ranges::data(__r)), __size_{ranges::size(__r)} {} - - template <__span_array_convertible<element_type> _OtherElementType, size_t _OtherExtent> - _LIBCPP_HIDE_FROM_ABI - constexpr span(const span<_OtherElementType, _OtherExtent>& __other) noexcept - : __data_{__other.data()}, __size_{__other.size()} {} - - template <size_t _Count> - _LIBCPP_HIDE_FROM_ABI - constexpr span<element_type, _Count> first() const noexcept - { - _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(_Count <= size(), "span<T>::first<Count>(): Count out of range"); - return span<element_type, _Count>{data(), _Count}; - } - - template <size_t _Count> - _LIBCPP_HIDE_FROM_ABI - constexpr span<element_type, _Count> last() const noexcept - { - _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(_Count <= size(), "span<T>::last<Count>(): Count out of range"); - return span<element_type, _Count>{data() + size() - _Count, _Count}; - } - - _LIBCPP_HIDE_FROM_ABI - constexpr span<element_type, dynamic_extent> first(size_type __count) const noexcept - { - _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__count <= size(), "span<T>::first(count): count out of range"); - return {data(), __count}; - } - - _LIBCPP_HIDE_FROM_ABI - constexpr span<element_type, dynamic_extent> last (size_type __count) const noexcept - { - _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__count <= size(), "span<T>::last(count): count out of range"); - return {data() + size() - __count, __count}; - } - - template <size_t _Offset, size_t _Count = dynamic_extent> - _LIBCPP_HIDE_FROM_ABI - constexpr span<element_type, _Count> subspan() const noexcept - { - _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS( - _Offset <= size(), "span<T>::subspan<Offset, Count>(): Offset out of range"); - _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(_Count == dynamic_extent || _Count <= size() - _Offset, - "span<T>::subspan<Offset, Count>(): Offset + Count out of range"); - return span<element_type, _Count>{data() + _Offset, _Count == dynamic_extent ? size() - _Offset : _Count}; - } - - constexpr span<element_type, dynamic_extent> - _LIBCPP_HIDE_FROM_ABI - subspan(size_type __offset, size_type __count = dynamic_extent) const noexcept - { - _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__offset <= size(), "span<T>::subspan(offset, count): offset out of range"); - if (__count == dynamic_extent) - return {data() + __offset, size() - __offset}; - _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS( - __count <= size() - __offset, "span<T>::subspan(offset, count): offset + count out of range"); - return {data() + __offset, __count}; - } - - _LIBCPP_HIDE_FROM_ABI constexpr size_type size() const noexcept { return __size_; } - _LIBCPP_HIDE_FROM_ABI constexpr size_type size_bytes() const noexcept { return __size_ * sizeof(element_type); } - [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool empty() const noexcept { return __size_ == 0; } - - _LIBCPP_HIDE_FROM_ABI constexpr reference operator[](size_type __idx) const noexcept - { - _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__idx < size(), "span<T>::operator[](index): index out of range"); - return __data_[__idx]; - } - - _LIBCPP_HIDE_FROM_ABI constexpr reference front() const noexcept - { - _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "span<T>::front() on empty span"); - return __data_[0]; - } - - _LIBCPP_HIDE_FROM_ABI constexpr reference back() const noexcept - { - _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "span<T>::back() on empty span"); - return __data_[size()-1]; - } - - - _LIBCPP_HIDE_FROM_ABI constexpr pointer data() const noexcept { return __data_; } - -// [span.iter], span iterator support - _LIBCPP_HIDE_FROM_ABI constexpr iterator begin() const noexcept { -#ifdef _LIBCPP_ABI_BOUNDED_ITERATORS - return std::__make_bounded_iter(data(), data(), data() + size()); -#else - return iterator(data()); -#endif - } - _LIBCPP_HIDE_FROM_ABI constexpr iterator end() const noexcept { -#ifdef _LIBCPP_ABI_BOUNDED_ITERATORS - return std::__make_bounded_iter(data() + size(), data(), data() + size()); -#else - return iterator(data() + size()); -#endif - } - _LIBCPP_HIDE_FROM_ABI constexpr reverse_iterator rbegin() const noexcept { return reverse_iterator(end()); } - _LIBCPP_HIDE_FROM_ABI constexpr reverse_iterator rend() const noexcept { return reverse_iterator(begin()); } - - _LIBCPP_HIDE_FROM_ABI span<const byte, dynamic_extent> __as_bytes() const noexcept - { return {reinterpret_cast<const byte *>(data()), size_bytes()}; } - - _LIBCPP_HIDE_FROM_ABI span<byte, dynamic_extent> __as_writable_bytes() const noexcept - { return {reinterpret_cast<byte *>(data()), size_bytes()}; } + // constants and types + using element_type = _Tp; + using value_type = remove_cv_t<_Tp>; + using size_type = size_t; + using difference_type = ptrdiff_t; + using pointer = _Tp*; + using const_pointer = const _Tp*; + using reference = _Tp&; + using const_reference = const _Tp&; +# ifdef _LIBCPP_ABI_BOUNDED_ITERATORS + using iterator = __bounded_iter<pointer>; +# else + using iterator = __wrap_iter<pointer>; +# endif + using reverse_iterator = std::reverse_iterator<iterator>; + + static constexpr size_type extent = dynamic_extent; + + // [span.cons], span constructors, copy, assignment, and destructor + _LIBCPP_HIDE_FROM_ABI constexpr span() noexcept : __data_{nullptr}, __size_{0} {} + + constexpr span(const span&) noexcept = default; + constexpr span& operator=(const span&) noexcept = default; + + template <__span_compatible_iterator<element_type> _It> + _LIBCPP_HIDE_FROM_ABI constexpr span(_It __first, size_type __count) + : __data_{std::to_address(__first)}, __size_{__count} {} + + template <__span_compatible_iterator<element_type> _It, __span_compatible_sentinel_for<_It> _End> + _LIBCPP_HIDE_FROM_ABI constexpr span(_It __first, _End __last) + : __data_(std::to_address(__first)), __size_(__last - __first) { + _LIBCPP_ASSERT_VALID_INPUT_RANGE(__last - __first >= 0, "invalid range in span's constructor (iterator, sentinel)"); + } + + template <size_t _Sz> + _LIBCPP_HIDE_FROM_ABI constexpr span(type_identity_t<element_type> (&__arr)[_Sz]) noexcept + : __data_{__arr}, __size_{_Sz} {} + + template <__span_array_convertible<element_type> _OtherElementType, size_t _Sz> + _LIBCPP_HIDE_FROM_ABI constexpr span(array<_OtherElementType, _Sz>& __arr) noexcept + : __data_{__arr.data()}, __size_{_Sz} {} + + template <class _OtherElementType, size_t _Sz> + requires __span_array_convertible<const _OtherElementType, element_type> + _LIBCPP_HIDE_FROM_ABI constexpr span(const array<_OtherElementType, _Sz>& __arr) noexcept + : __data_{__arr.data()}, __size_{_Sz} {} + + template <__span_compatible_range<element_type> _Range> + _LIBCPP_HIDE_FROM_ABI constexpr span(_Range&& __r) : __data_(ranges::data(__r)), __size_{ranges::size(__r)} {} + + template <__span_array_convertible<element_type> _OtherElementType, size_t _OtherExtent> + _LIBCPP_HIDE_FROM_ABI constexpr span(const span<_OtherElementType, _OtherExtent>& __other) noexcept + : __data_{__other.data()}, __size_{__other.size()} {} + + template <size_t _Count> + _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, _Count> first() const noexcept { + _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(_Count <= size(), "span<T>::first<Count>(): Count out of range"); + return span<element_type, _Count>{data(), _Count}; + } + + template <size_t _Count> + _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, _Count> last() const noexcept { + _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(_Count <= size(), "span<T>::last<Count>(): Count out of range"); + return span<element_type, _Count>{data() + size() - _Count, _Count}; + } + + _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, dynamic_extent> first(size_type __count) const noexcept { + _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__count <= size(), "span<T>::first(count): count out of range"); + return {data(), __count}; + } + + _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, dynamic_extent> last(size_type __count) const noexcept { + _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__count <= size(), "span<T>::last(count): count out of range"); + return {data() + size() - __count, __count}; + } + + template <size_t _Offset, size_t _Count = dynamic_extent> + _LIBCPP_HIDE_FROM_ABI constexpr span<element_type, _Count> subspan() const noexcept { + _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(_Offset <= size(), "span<T>::subspan<Offset, Count>(): Offset out of range"); + _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(_Count == dynamic_extent || _Count <= size() - _Offset, + "span<T>::subspan<Offset, Count>(): Offset + Count out of range"); + return span<element_type, _Count>{data() + _Offset, _Count == dynamic_extent ? size() - _Offset : _Count}; + } + + constexpr span<element_type, dynamic_extent> _LIBCPP_HIDE_FROM_ABI + subspan(size_type __offset, size_type __count = dynamic_extent) const noexcept { + _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__offset <= size(), "span<T>::subspan(offset, count): offset out of range"); + if (__count == dynamic_extent) + return {data() + __offset, size() - __offset}; + _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS( + __count <= size() - __offset, "span<T>::subspan(offset, count): offset + count out of range"); + return {data() + __offset, __count}; + } + + _LIBCPP_HIDE_FROM_ABI constexpr size_type size() const noexcept { return __size_; } + _LIBCPP_HIDE_FROM_ABI constexpr size_type size_bytes() const noexcept { return __size_ * sizeof(element_type); } + [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool empty() const noexcept { return __size_ == 0; } + + _LIBCPP_HIDE_FROM_ABI constexpr reference operator[](size_type __idx) const noexcept { + _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__idx < size(), "span<T>::operator[](index): index out of range"); + return __data_[__idx]; + } + + _LIBCPP_HIDE_FROM_ABI constexpr reference front() const noexcept { + _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "span<T>::front() on empty span"); + return __data_[0]; + } + + _LIBCPP_HIDE_FROM_ABI constexpr reference back() const noexcept { + _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "span<T>::back() on empty span"); + return __data_[size() - 1]; + } + + _LIBCPP_HIDE_FROM_ABI constexpr pointer data() const noexcept { return __data_; } + + // [span.iter], span iterator support + _LIBCPP_HIDE_FROM_ABI constexpr iterator begin() const noexcept { +# ifdef _LIBCPP_ABI_BOUNDED_ITERATORS + return std::__make_bounded_iter(data(), data(), data() + size()); +# else + return iterator(data()); +# endif + } + _LIBCPP_HIDE_FROM_ABI constexpr iterator end() const noexcept { +# ifdef _LIBCPP_ABI_BOUNDED_ITERATORS + return std::__make_bounded_iter(data() + size(), data(), data() + size()); +# else + return iterator(data() + size()); +# endif + } + _LIBCPP_HIDE_FROM_ABI constexpr reverse_iterator rbegin() const noexcept { return reverse_iterator(end()); } + _LIBCPP_HIDE_FROM_ABI constexpr reverse_iterator rend() const noexcept { return reverse_iterator(begin()); } + + _LIBCPP_HIDE_FROM_ABI span<const byte, dynamic_extent> __as_bytes() const noexcept { + return {reinterpret_cast<const byte*>(data()), size_bytes()}; + } + + _LIBCPP_HIDE_FROM_ABI span<byte, dynamic_extent> __as_writable_bytes() const noexcept { + return {reinterpret_cast<byte*>(data()), size_bytes()}; + } private: - pointer __data_; - size_type __size_; + pointer __data_; + size_type __size_; }; template <class _Tp, size_t _Extent> @@ -562,31 +520,32 @@ inline constexpr bool ranges::enable_view<span<_ElementType, _Extent>> = true; // as_bytes & as_writable_bytes template <class _Tp, size_t _Extent> -_LIBCPP_HIDE_FROM_ABI -auto as_bytes(span<_Tp, _Extent> __s) noexcept -{ return __s.__as_bytes(); } +_LIBCPP_HIDE_FROM_ABI auto as_bytes(span<_Tp, _Extent> __s) noexcept { + return __s.__as_bytes(); +} -template <class _Tp, size_t _Extent> requires(!is_const_v<_Tp>) -_LIBCPP_HIDE_FROM_ABI -auto as_writable_bytes(span<_Tp, _Extent> __s) noexcept -{ return __s.__as_writable_bytes(); } +template <class _Tp, size_t _Extent> + requires(!is_const_v<_Tp>) +_LIBCPP_HIDE_FROM_ABI auto as_writable_bytes(span<_Tp, _Extent> __s) noexcept { + return __s.__as_writable_bytes(); +} -#if _LIBCPP_STD_VER >= 20 -template<contiguous_iterator _It, class _EndOrSize> - span(_It, _EndOrSize) -> span<remove_reference_t<iter_reference_t<_It>>>; -#endif // _LIBCPP_STD_VER >= 20 +# if _LIBCPP_STD_VER >= 20 +template <contiguous_iterator _It, class _EndOrSize> +span(_It, _EndOrSize) -> span<remove_reference_t<iter_reference_t<_It>>>; +# endif // _LIBCPP_STD_VER >= 20 -template<class _Tp, size_t _Sz> - span(_Tp (&)[_Sz]) -> span<_Tp, _Sz>; +template <class _Tp, size_t _Sz> +span(_Tp (&)[_Sz]) -> span<_Tp, _Sz>; -template<class _Tp, size_t _Sz> - span(array<_Tp, _Sz>&) -> span<_Tp, _Sz>; +template <class _Tp, size_t _Sz> +span(array<_Tp, _Sz>&) -> span<_Tp, _Sz>; -template<class _Tp, size_t _Sz> - span(const array<_Tp, _Sz>&) -> span<const _Tp, _Sz>; +template <class _Tp, size_t _Sz> +span(const array<_Tp, _Sz>&) -> span<const _Tp, _Sz>; -template<ranges::contiguous_range _Range> - span(_Range&&) -> span<remove_reference_t<ranges::range_reference_t<_Range>>>; +template <ranges::contiguous_range _Range> +span(_Range&&) -> span<remove_reference_t<ranges::range_reference_t<_Range>>>; #endif // _LIBCPP_STD_VER >= 20 |