Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Remove obsolete conditional compilation from <compare> #1049

Merged
merged 12 commits into from
Jul 20, 2020
Merged

Remove obsolete conditional compilation from <compare> #1049

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
12 commits
Select commit Hold shift + click to select a range
eddf626
Remove obsolete conditional compilation from <compare>
CaseyCarter Jul 16, 2020
381d91b
Break <compare> ABI again, and fix #1050
CaseyCarter Jul 16, 2020
0803efa
Review comments
CaseyCarter Jul 17, 2020
6a1e8d9
Audit for all occurrences of __cpp_impl_three_way_comparison
CaseyCarter Jul 17, 2020
7dffee7
Test 0 < MEOW
CaseyCarter Jul 17, 2020
3b2ec70
Statementreply's review comments; eliminate redundant coverage
CaseyCarter Jul 17, 2020
89b380b
Review comments
CaseyCarter Jul 17, 2020
0209d3e
Workaround DevCom-1117991 and document partial_ordering::operator<=
CaseyCarter Jul 18, 2020
b6013a9
Document partial_ordering::operator<=> as well
CaseyCarter Jul 18, 2020
262caaa
Fix math (0x80 - 1 == 0x7f), Oxford commas, iff, rewrap.
StephanTLavavej Jul 18, 2020
9c67ea7
Merge branch 'master' into compare
StephanTLavavej Jul 18, 2020
9bb982c
Simplify compiler bug workaround
StephanTLavavej Jul 18, 2020
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
98 changes: 26 additions & 72 deletions stl/inc/compare
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -32,7 +32,7 @@ using _Compare_t = signed char;
// These "pretty" enumerator names are safe since they reuse names of user-facing entities.
enum class _Compare_eq : _Compare_t { equal = 0, equivalent = equal };
enum class _Compare_ord : _Compare_t { less = -1, greater = 1 };
enum class _Compare_ncmp : _Compare_t { unordered = -127 };
enum class _Compare_ncmp : _Compare_t { unordered = -128 };
CaseyCarter marked this conversation as resolved.
Show resolved Hide resolved

// CLASS partial_ordering
class partial_ordering {
Expand All @@ -53,21 +53,7 @@ public:
return _Val._Value == 0;
}

#if defined(__cpp_impl_three_way_comparison) && __cpp_impl_three_way_comparison >= 201902L
_NODISCARD friend constexpr bool operator==(const partial_ordering&, const partial_ordering&) noexcept = default;
#else // ^^^ supports <=> and P1185 / supports neither vvv
_NODISCARD friend constexpr bool operator!=(const partial_ordering _Val, _Literal_zero) noexcept {
return _Val._Value != 0;
}

_NODISCARD friend constexpr bool operator==(_Literal_zero, const partial_ordering _Val) noexcept {
return 0 == _Val._Value;
}

_NODISCARD friend constexpr bool operator!=(_Literal_zero, const partial_ordering _Val) noexcept {
return 0 != _Val._Value;
}
#endif // defined(__cpp_impl_three_way_comparison) && __cpp_impl_three_way_comparison >= 201902L
_NODISCARD friend constexpr bool operator==(partial_ordering, partial_ordering) noexcept = default;

_NODISCARD friend constexpr bool operator<(const partial_ordering _Val, _Literal_zero) noexcept {
return _Val._Value == static_cast<_Compare_t>(_Compare_ord::less);
Expand All @@ -78,44 +64,44 @@ public:
}

_NODISCARD friend constexpr bool operator<=(const partial_ordering _Val, _Literal_zero) noexcept {
return _Val._Value <= 0 && _Val._Is_ordered();
// The stored value is either less (0xff), equivalent (0x00), greater (0x01), or unordered (0x80).
// Subtracting from 0 produces either 0x01, 0x00, 0xff, or 0x80. The result is greater than or equal to 0
// if and only if the initial value was less or equivalent, for which we want to return true.
return static_cast<signed char>(0 - static_cast<unsigned int>(_Val._Value)) >= 0;
}

_NODISCARD friend constexpr bool operator>=(const partial_ordering _Val, _Literal_zero) noexcept {
return _Val._Value >= 0;
}

_NODISCARD friend constexpr bool operator<(_Literal_zero, const partial_ordering _Val) noexcept {
return 0 < _Val._Value;
return _Val > 0;
}

_NODISCARD friend constexpr bool operator>(_Literal_zero, const partial_ordering _Val) noexcept {
return 0 > _Val._Value && _Val._Is_ordered();
return _Val < 0;
}

_NODISCARD friend constexpr bool operator<=(_Literal_zero, const partial_ordering _Val) noexcept {
return 0 <= _Val._Value;
return _Val >= 0;
}

_NODISCARD friend constexpr bool operator>=(_Literal_zero, const partial_ordering _Val) noexcept {
return 0 >= _Val._Value && _Val._Is_ordered();
return _Val <= 0;
}

#ifdef __cpp_impl_three_way_comparison
_NODISCARD friend constexpr partial_ordering operator<=>(const partial_ordering _Val, _Literal_zero) noexcept {
return _Val;
}

_NODISCARD friend constexpr partial_ordering operator<=>(_Literal_zero, const partial_ordering _Val) noexcept {
return partial_ordering{static_cast<_Compare_ord>(-_Val._Value)};
// The stored value is either less (0xff), equivalent (0x00), greater (0x01), or unordered (0x80).
// Subtracting from 0 produces either 0x01, 0x00, 0xff, or 0x80. Note that the effect is to
// exchange less for greater (and vice versa), while leaving equivalent and unordered unchanged.
return partial_ordering{static_cast<_Compare_ord>(0 - static_cast<unsigned int>(_Val._Value))};
}
#endif // __cpp_impl_three_way_comparison

private:
_NODISCARD constexpr bool _Is_ordered() const noexcept {
return _Value != static_cast<_Compare_t>(_Compare_ncmp::unordered);
}

_Compare_t _Value;
};

Expand Down Expand Up @@ -144,21 +130,7 @@ public:
return _Val._Value == 0;
}

#if defined(__cpp_impl_three_way_comparison) && __cpp_impl_three_way_comparison >= 201902L
_NODISCARD friend constexpr bool operator==(const weak_ordering&, const weak_ordering&) noexcept = default;
#else // ^^^ supports <=> and P1185 / supports neither vvv
_NODISCARD friend constexpr bool operator!=(const weak_ordering _Val, _Literal_zero) noexcept {
return _Val._Value != 0;
}

_NODISCARD friend constexpr bool operator==(_Literal_zero, const weak_ordering _Val) noexcept {
return 0 == _Val._Value;
}

_NODISCARD friend constexpr bool operator!=(_Literal_zero, const weak_ordering _Val) noexcept {
return 0 != _Val._Value;
}
#endif // defined(__cpp_impl_three_way_comparison) && __cpp_impl_three_way_comparison >= 201902L
_NODISCARD friend constexpr bool operator==(weak_ordering, weak_ordering) noexcept = default;

_NODISCARD friend constexpr bool operator<(const weak_ordering _Val, _Literal_zero) noexcept {
return _Val._Value < 0;
Expand All @@ -177,30 +149,28 @@ public:
}

_NODISCARD friend constexpr bool operator<(_Literal_zero, const weak_ordering _Val) noexcept {
return 0 < _Val._Value;
return _Val > 0;
}

_NODISCARD friend constexpr bool operator>(_Literal_zero, const weak_ordering _Val) noexcept {
return 0 > _Val._Value;
return _Val < 0;
}

_NODISCARD friend constexpr bool operator<=(_Literal_zero, const weak_ordering _Val) noexcept {
return 0 <= _Val._Value;
return _Val >= 0;
}

_NODISCARD friend constexpr bool operator>=(_Literal_zero, const weak_ordering _Val) noexcept {
return 0 >= _Val._Value;
return _Val <= 0;
}

#ifdef __cpp_impl_three_way_comparison
_NODISCARD friend constexpr weak_ordering operator<=>(const weak_ordering _Val, _Literal_zero) noexcept {
return _Val;
}

_NODISCARD friend constexpr weak_ordering operator<=>(_Literal_zero, const weak_ordering _Val) noexcept {
return weak_ordering{static_cast<_Compare_ord>(-_Val._Value)};
}
#endif // __cpp_impl_three_way_comparison

private:
_Compare_t _Value;
CaseyCarter marked this conversation as resolved.
Show resolved Hide resolved
Expand Down Expand Up @@ -235,21 +205,7 @@ public:
return _Val._Value == 0;
}

#if defined(__cpp_impl_three_way_comparison) && __cpp_impl_three_way_comparison >= 201902L
_NODISCARD friend constexpr bool operator==(const strong_ordering&, const strong_ordering&) noexcept = default;
#else // ^^^ supports <=> and P1185 / supports neither vvv
_NODISCARD friend constexpr bool operator!=(const strong_ordering _Val, _Literal_zero) noexcept {
return _Val._Value != 0;
}

_NODISCARD friend constexpr bool operator==(_Literal_zero, const strong_ordering _Val) noexcept {
return 0 == _Val._Value;
}

_NODISCARD friend constexpr bool operator!=(_Literal_zero, const strong_ordering _Val) noexcept {
return 0 != _Val._Value;
}
#endif // defined(__cpp_impl_three_way_comparison) && __cpp_impl_three_way_comparison >= 201902L
_NODISCARD friend constexpr bool operator==(strong_ordering, strong_ordering) noexcept = default;

_NODISCARD friend constexpr bool operator<(const strong_ordering _Val, _Literal_zero) noexcept {
return _Val._Value < 0;
Expand All @@ -268,30 +224,28 @@ public:
}

_NODISCARD friend constexpr bool operator<(_Literal_zero, const strong_ordering _Val) noexcept {
return 0 < _Val._Value;
return _Val > 0;
}

_NODISCARD friend constexpr bool operator>(_Literal_zero, const strong_ordering _Val) noexcept {
return 0 > _Val._Value;
return _Val < 0;
}

_NODISCARD friend constexpr bool operator<=(_Literal_zero, const strong_ordering _Val) noexcept {
return 0 <= _Val._Value;
return _Val >= 0;
}

_NODISCARD friend constexpr bool operator>=(_Literal_zero, const strong_ordering _Val) noexcept {
return 0 >= _Val._Value;
return _Val <= 0;
}

#ifdef __cpp_impl_three_way_comparison
_NODISCARD friend constexpr strong_ordering operator<=>(const strong_ordering _Val, _Literal_zero) noexcept {
return _Val;
}

_NODISCARD friend constexpr strong_ordering operator<=>(_Literal_zero, const strong_ordering _Val) noexcept {
return strong_ordering{static_cast<_Compare_ord>(-_Val._Value)};
}
#endif // __cpp_impl_three_way_comparison

private:
_Compare_t _Value;
Expand Down Expand Up @@ -364,7 +318,7 @@ struct common_comparison_category {
using type = common_comparison_category_t<_Types...>;
};

#if defined(__cpp_impl_three_way_comparison) && defined(__cpp_lib_concepts)
#ifdef __cpp_lib_concepts
// clang-format off
template <class _Ty, class _Cat>
concept _Compares_as = same_as<common_comparison_category_t<_Ty, _Cat>, _Cat>;
Expand Down Expand Up @@ -409,7 +363,7 @@ struct compare_three_way {
using is_transparent = int;
};
// clang-format on
#endif // defined(__cpp_impl_three_way_comparison) && defined(__cpp_lib_concepts)
#endif // __cpp_lib_concepts

// Other components not yet implemented
_STD_END
Expand Down
30 changes: 1 addition & 29 deletions stl/inc/span
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -12,13 +12,11 @@
#if !_HAS_CXX20
#pragma message("The contents of <span> are available only with C++20 or later.")
#else // ^^^ !_HAS_CXX20 / _HAS_CXX20 vvv
#include <compare>
#include <cstddef>
#include <type_traits>
#include <xutility>

#if defined(__cpp_impl_three_way_comparison) && __cpp_impl_three_way_comparison >= 201902L
#include <compare>
#endif // defined(__cpp_impl_three_way_comparison) && __cpp_impl_three_way_comparison >= 201902L

#pragma pack(push, _CRT_PACKING)
#pragma warning(push, _STL_WARNING_LEVEL)
Expand Down Expand Up @@ -153,39 +151,13 @@ struct _Span_iterator {
return _Myptr == _Right._Myptr;
}

#if defined(__cpp_impl_three_way_comparison) && __cpp_impl_three_way_comparison >= 201902L
_NODISCARD constexpr strong_ordering operator<=>(const _Span_iterator& _Right) const noexcept {
#if _ITERATOR_DEBUG_LEVEL >= 1
_STL_VERIFY(
_Mybegin == _Right._Mybegin && _Myend == _Right._Myend, "cannot compare incompatible span iterators");
#endif // _ITERATOR_DEBUG_LEVEL >= 1
return _Myptr <=> _Right._Myptr;
}
#else // ^^^ use spaceship / no spaceship vvv
_NODISCARD constexpr bool operator!=(const _Span_iterator& _Right) const noexcept {
return !(*this == _Right);
}

_NODISCARD constexpr bool operator<(const _Span_iterator& _Right) const noexcept {
#if _ITERATOR_DEBUG_LEVEL >= 1
_STL_VERIFY(
_Mybegin == _Right._Mybegin && _Myend == _Right._Myend, "cannot compare incompatible span iterators");
#endif // _ITERATOR_DEBUG_LEVEL >= 1
return _Myptr < _Right._Myptr;
}

_NODISCARD constexpr bool operator>(const _Span_iterator& _Right) const noexcept {
return _Right < *this;
}

_NODISCARD constexpr bool operator<=(const _Span_iterator& _Right) const noexcept {
return !(_Right < *this);
}

_NODISCARD constexpr bool operator>=(const _Span_iterator& _Right) const noexcept {
return !(*this < _Right);
}
#endif // defined(__cpp_impl_three_way_comparison) && __cpp_impl_three_way_comparison >= 201902L

#if _ITERATOR_DEBUG_LEVEL >= 1
friend constexpr void _Verify_range(const _Span_iterator& _First, const _Span_iterator& _Last) noexcept {
Expand Down
31 changes: 8 additions & 23 deletions stl/inc/xutility
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -2105,13 +2105,13 @@ _NODISCARD _CONSTEXPR17 bool operator>=(const reverse_iterator<_BidIt1>& _Left,
#endif // __cpp_lib_concepts
{ return _Left._Get_current() <= _Right._Get_current(); }

#if defined(__cpp_impl_three_way_comparison) && defined(__cpp_lib_concepts)
#ifdef __cpp_lib_concepts
template <class _BidIt1, three_way_comparable_with<_BidIt1> _BidIt2>
_NODISCARD constexpr compare_three_way_result_t<_BidIt1, _BidIt2> operator<=>(
const reverse_iterator<_BidIt1>& _Left, const reverse_iterator<_BidIt2>& _Right) {
return _Right._Get_current() <=> _Left._Get_current();
}
#endif // defined(__cpp_impl_three_way_comparison) && defined(__cpp_lib_concepts)
#endif // __cpp_lib_concepts

template <class _BidIt1, class _BidIt2>
_NODISCARD _CONSTEXPR17 auto operator-(const reverse_iterator<_BidIt1>& _Left, const reverse_iterator<_BidIt2>& _Right)
Expand Down Expand Up @@ -4103,12 +4103,12 @@ _NODISCARD _CONSTEXPR17 bool operator==(const move_iterator<_Iter1>& _Left, cons
#endif // __cpp_lib_concepts
{ return _Left.base() == _Right.base(); }

#if !_HAS_CXX20 || __cpp_impl_three_way_comparison < 201902L
#if !_HAS_CXX20
template <class _Iter1, class _Iter2>
_NODISCARD _CONSTEXPR17 bool operator!=(const move_iterator<_Iter1>& _Left, const move_iterator<_Iter2>& _Right) {
return !(_Left == _Right);
}
#endif // !_HAS_CXX20 || __cpp_impl_three_way_comparison < 201902L
#endif // !_HAS_CXX20

template <class _Iter1, class _Iter2>
_NODISCARD _CONSTEXPR17 bool operator<(const move_iterator<_Iter1>& _Left, const move_iterator<_Iter2>& _Right)
Expand Down Expand Up @@ -4148,13 +4148,13 @@ _NODISCARD _CONSTEXPR17 bool operator>=(const move_iterator<_Iter1>& _Left, cons
#endif // __cpp_lib_concepts
{ return !(_Left < _Right); }

#if defined(__cpp_impl_three_way_comparison) && defined(__cpp_lib_concepts)
#ifdef __cpp_lib_concepts
template <class _Iter1, three_way_comparable_with<_Iter1> _Iter2>
_NODISCARD constexpr compare_three_way_result_t<_Iter1, _Iter2> operator<=>(
const move_iterator<_Iter1>& _Left, const move_iterator<_Iter2>& _Right) {
return _Left.base() <=> _Right.base();
}
#endif // defined(__cpp_impl_three_way_comparison) && defined(__cpp_lib_concepts)
#endif // __cpp_lib_concepts

template <class _Iter1, class _Iter2>
_NODISCARD _CONSTEXPR17 auto operator-(const move_iterator<_Iter1>& _Left, const move_iterator<_Iter2>& _Right)
Expand Down Expand Up @@ -4195,21 +4195,6 @@ namespace _Unreachable_sentinel_detail {
_NODISCARD friend constexpr bool operator==(const unreachable_sentinel_t&, const _Winc&) noexcept {
return false;
}
#if !defined(__cpp_impl_three_way_comparison) || __cpp_impl_three_way_comparison < 201902L
template <weakly_incrementable _Winc>
_NODISCARD friend constexpr bool operator==(const _Winc&, const unreachable_sentinel_t&) noexcept {
return false;
}

template <weakly_incrementable _Winc>
_NODISCARD friend constexpr bool operator!=(const unreachable_sentinel_t&, const _Winc&) noexcept {
return true;
}
template <weakly_incrementable _Winc>
_NODISCARD friend constexpr bool operator!=(const _Winc&, const unreachable_sentinel_t&) noexcept {
return true;
}
#endif // !defined(__cpp_impl_three_way_comparison) || __cpp_impl_three_way_comparison < 201902L
};
} // namespace _Unreachable_sentinel_detail
struct unreachable_sentinel_t : _Unreachable_sentinel_detail::_Base {}; // TRANSITION, /permissive-
Expand Down Expand Up @@ -5236,7 +5221,7 @@ _NODISCARD bool lexicographical_compare(
}
#endif // _HAS_CXX17

#if defined(__cpp_impl_three_way_comparison) && defined(__cpp_lib_concepts)
#ifdef __cpp_lib_concepts
// FUNCTION TEMPLATE lexicographical_compare_three_way
template <class _InIt1, class _InIt2, class _Cmp>
_NODISCARD constexpr auto lexicographical_compare_three_way(
Expand Down Expand Up @@ -5294,7 +5279,7 @@ _NODISCARD constexpr auto lexicographical_compare_three_way(
_InIt1 _First1, _InIt1 _Last1, _InIt2 _First2, _InIt2 _Last2) {
return _STD lexicographical_compare_three_way(_First1, _Last1, _First2, _Last2, compare_three_way{});
}
#endif // defined(__cpp_impl_three_way_comparison) && defined(__cpp_lib_concepts)
#endif // __cpp_lib_concepts

// FUNCTION TEMPLATE find
template <class _Ty>
Expand Down
Loading