First part of P1227R2 - change span over to use 'size_t' instead of 'ptrdiff_t'. Reviewed as https://reviews.llvm.org/D58639.
llvm-svn: 354936
Cr-Mirrored-From: sso://chromium.googlesource.com/_direct/external/github.com/llvm/llvm-project
Cr-Mirrored-Commit: 7ad06a9319fdd54a890f75026049e3e4bcfa061e
diff --git a/include/iterator b/include/iterator
index 242f188..ce0be3d 100644
--- a/include/iterator
+++ b/include/iterator
@@ -1442,7 +1442,7 @@
template <class _Up> friend class __wrap_iter;
template <class _CharT, class _Traits, class _Alloc> friend class basic_string;
template <class _Tp, class _Alloc> friend class _LIBCPP_TEMPLATE_VIS vector;
- template <class _Tp, ptrdiff_t> friend class _LIBCPP_TEMPLATE_VIS span;
+ template <class _Tp, size_t> friend class _LIBCPP_TEMPLATE_VIS span;
template <class _Iter1, class _Iter2>
_LIBCPP_CONSTEXPR_IF_NODEBUG friend
diff --git a/include/span b/include/span
index 0edf92c..606f9a9 100644
--- a/include/span
+++ b/include/span
@@ -16,36 +16,36 @@
namespace std {
// constants
-inline constexpr ptrdiff_t dynamic_extent = -1;
+inline constexpr size_t dynamic_extent = numeric_limits<size_t>::max();
// [views.span], class template span
-template <class ElementType, ptrdiff_t Extent = dynamic_extent>
+template <class ElementType, size_t Extent = dynamic_extent>
class span;
// [span.objectrep], views of object representation
-template <class ElementType, ptrdiff_t Extent>
+template <class ElementType, size_t Extent>
span<const byte, ((Extent == dynamic_extent) ? dynamic_extent :
(static_cast<ptrdiff_t>(sizeof(ElementType)) * Extent))> as_bytes(span<ElementType, Extent> s) noexcept;
-template <class ElementType, ptrdiff_t Extent>
+template <class ElementType, size_t Extent>
span< byte, ((Extent == dynamic_extent) ? dynamic_extent :
(static_cast<ptrdiff_t>(sizeof(ElementType)) * Extent))> as_writable_bytes(span<ElementType, Extent> s) noexcept;
namespace std {
-template <class ElementType, ptrdiff_t Extent = dynamic_extent>
+template <class ElementType, size_t Extent = dynamic_extent>
class span {
public:
// constants and types
using element_type = ElementType;
using value_type = remove_cv_t<ElementType>;
- using index_type = ptrdiff_t;
+ using index_type = size_t;
using difference_type = ptrdiff_t;
using pointer = element_type*;
using const_pointer = const element_type*;
using reference = element_type&;
- using iterator = implementation-defined;
using const_reference = const element_type&;
+ using iterator = implementation-defined;
using const_iterator = implementation-defined;
using reverse_iterator = std::reverse_iterator<iterator>;
using const_reverse_iterator = std::reverse_iterator<const_iterator>;
@@ -66,17 +66,17 @@
template <class Container>
constexpr span(const Container& cont);
constexpr span(const span& other) noexcept = default;
- template <class OtherElementType, ptrdiff_t OtherExtent>
+ template <class OtherElementType, size_t OtherExtent>
constexpr span(const span<OtherElementType, OtherExtent>& s) noexcept;
~span() noexcept = default;
constexpr span& operator=(const span& other) noexcept = default;
// [span.sub], span subviews
- template <ptrdiff_t Count>
+ template <size_t Count>
constexpr span<element_type, Count> first() const;
- template <ptrdiff_t Count>
+ template <size_t Count>
constexpr span<element_type, Count> last() const;
- template <ptrdiff_t Offset, ptrdiff_t Count = dynamic_extent>
+ template <size_t Offset, size_t Count = dynamic_extent>
constexpr span<element_type, see below> subspan() const;
constexpr span<element_type, dynamic_extent> first(index_type count) const;
@@ -143,14 +143,14 @@
#if _LIBCPP_STD_VER > 17
-inline constexpr ptrdiff_t dynamic_extent = -1;
-template <typename _Tp, ptrdiff_t _Extent = dynamic_extent> class span;
+inline constexpr size_t dynamic_extent = numeric_limits<size_t>::max();
+template <typename _Tp, size_t _Extent = dynamic_extent> class span;
template <class _Tp>
struct __is_span_impl : public false_type {};
-template <class _Tp, ptrdiff_t _Extent>
+template <class _Tp, size_t _Extent>
struct __is_span_impl<span<_Tp, _Extent>> : public true_type {};
template <class _Tp>
@@ -189,13 +189,13 @@
: public true_type {};
-template <typename _Tp, ptrdiff_t _Extent>
+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 index_type = ptrdiff_t;
+ using index_type = size_t;
using difference_type = ptrdiff_t;
using pointer = _Tp *;
using const_pointer = const _Tp *;
@@ -244,20 +244,18 @@
// ~span() noexcept = default;
- template <ptrdiff_t _Count>
+ template <size_t _Count>
inline _LIBCPP_INLINE_VISIBILITY
constexpr span<element_type, _Count> first() const noexcept
{
- static_assert(_Count >= 0, "Count must be >= 0 in span::first()");
static_assert(_Count <= _Extent, "Count out of range in span::first()");
return {data(), _Count};
}
- template <ptrdiff_t _Count>
+ template <size_t _Count>
inline _LIBCPP_INLINE_VISIBILITY
constexpr span<element_type, _Count> last() const noexcept
{
- static_assert(_Count >= 0, "Count must be >= 0 in span::last()");
static_assert(_Count <= _Extent, "Count out of range in span::last()");
return {data() + size() - _Count, _Count};
}
@@ -276,7 +274,7 @@
return {data() + size() - __count, __count};
}
- template <ptrdiff_t _Offset, ptrdiff_t _Count = dynamic_extent>
+ template <size_t _Offset, size_t _Count = dynamic_extent>
inline _LIBCPP_INLINE_VISIBILITY
constexpr auto subspan() const noexcept
-> span<element_type, _Count != dynamic_extent ? _Count : _Extent - _Offset>
@@ -359,7 +357,7 @@
// constants and types
using element_type = _Tp;
using value_type = remove_cv_t<_Tp>;
- using index_type = ptrdiff_t;
+ using index_type = size_t;
using difference_type = ptrdiff_t;
using pointer = _Tp *;
using const_pointer = const _Tp *;
@@ -379,7 +377,7 @@
constexpr span& operator=(const span&) noexcept = default;
_LIBCPP_INLINE_VISIBILITY constexpr span(pointer __ptr, index_type __count) : __data{__ptr}, __size{__count} {}
- _LIBCPP_INLINE_VISIBILITY constexpr span(pointer __f, pointer __l) : __data{__f}, __size{distance(__f, __l)} {}
+ _LIBCPP_INLINE_VISIBILITY constexpr span(pointer __f, pointer __l) : __data{__f}, __size{static_cast<size_t>(distance(__f, __l))} {}
template <size_t _Sz>
inline _LIBCPP_INLINE_VISIBILITY
@@ -406,7 +404,7 @@
: __data{_VSTD::data(__c)}, __size{(index_type) _VSTD::size(__c)} {}
- template <class _OtherElementType, ptrdiff_t _OtherExtent>
+ template <class _OtherElementType, size_t _OtherExtent>
inline _LIBCPP_INLINE_VISIBILITY
constexpr span(const span<_OtherElementType, _OtherExtent>& __other,
enable_if_t<
@@ -416,20 +414,18 @@
// ~span() noexcept = default;
- template <ptrdiff_t _Count>
+ template <size_t _Count>
inline _LIBCPP_INLINE_VISIBILITY
constexpr span<element_type, _Count> first() const noexcept
{
- static_assert(_Count >= 0, "Count must be >= 0 in span::first()");
_LIBCPP_ASSERT(_Count <= size(), "Count out of range in span::first()");
return {data(), _Count};
}
- template <ptrdiff_t _Count>
+ template <size_t _Count>
inline _LIBCPP_INLINE_VISIBILITY
constexpr span<element_type, _Count> last() const noexcept
{
- static_assert(_Count >= 0, "Count must be >= 0 in span::last()");
_LIBCPP_ASSERT(_Count <= size(), "Count out of range in span::last()");
return {data() + size() - _Count, _Count};
}
@@ -448,7 +444,7 @@
return {data() + size() - __count, __count};
}
- template <ptrdiff_t _Offset, ptrdiff_t _Count = dynamic_extent>
+ template <size_t _Offset, size_t _Count = dynamic_extent>
inline _LIBCPP_INLINE_VISIBILITY
constexpr span<_Tp, dynamic_extent> subspan() const noexcept
{
@@ -527,17 +523,17 @@
};
// as_bytes & as_writeable_bytes
-template <class _Tp, ptrdiff_t _Extent>
+template <class _Tp, size_t _Extent>
auto as_bytes(span<_Tp, _Extent> __s) noexcept
-> decltype(__s.__as_bytes())
{ return __s.__as_bytes(); }
-template <class _Tp, ptrdiff_t _Extent>
+template <class _Tp, size_t _Extent>
auto as_writeable_bytes(span<_Tp, _Extent> __s) noexcept
-> typename enable_if<!is_const_v<_Tp>, decltype(__s.__as_writeable_bytes())>::type
{ return __s.__as_writeable_bytes(); }
-template <class _Tp, ptrdiff_t _Extent>
+template <class _Tp, size_t _Extent>
constexpr void swap(span<_Tp, _Extent> &__lhs, span<_Tp, _Extent> &__rhs) noexcept
{ __lhs.swap(__rhs); }