Commit f851db3d authored by Arthur O'Dwyer's avatar Arthur O'Dwyer
Browse files

[libc++] [P0879] constexpr std::reverse, partition, *_permutation. 

After this patch, the only parts of P0879 that remain missing will be
std::nth_element, std::sort, and the heap/partial_sort algorithms.

Differential Revision: https://reviews.llvm.org/D93443
parent c4355670

libcxx/include/algorithm

+18 −18
Original line number Diff line number Diff line
@@ -267,7 +267,7 @@ template <class InputIterator, class OutputIterator, class BinaryPredicate> 
    unique_copy(InputIterator first, InputIterator last, OutputIterator result, BinaryPredicate pred);



template <class BidirectionalIterator>

    void

    constexpr void               // constexpr in C++20

    reverse(BidirectionalIterator first, BidirectionalIterator last);



template <class BidirectionalIterator, class OutputIterator>
@@ -316,7 +316,7 @@ template <class InputIterator, class Predicate> 
    is_partitioned(InputIterator first, InputIterator last, Predicate pred);



template <class ForwardIterator, class Predicate>

    ForwardIterator

    constexpr ForwardIterator  // constexpr in C++20

    partition(ForwardIterator first, ForwardIterator last, Predicate pred);



template <class InputIterator, class OutputIterator1,
@@ -626,19 +626,19 @@ template <class InputIterator1, class InputIterator2, class Compare> 
                            InputIterator2 first2, InputIterator2 last2, Compare comp);



template <class BidirectionalIterator>

    bool

    constexpr bool     // constexpr in C++20

    next_permutation(BidirectionalIterator first, BidirectionalIterator last);



template <class BidirectionalIterator, class Compare>

    bool

    constexpr bool     // constexpr in C++20

    next_permutation(BidirectionalIterator first, BidirectionalIterator last, Compare comp);



template <class BidirectionalIterator>

    bool

    constexpr bool     // constexpr in C++20

    prev_permutation(BidirectionalIterator first, BidirectionalIterator last);



template <class BidirectionalIterator, class Compare>

    bool

    constexpr bool     // constexpr in C++20

    prev_permutation(BidirectionalIterator first, BidirectionalIterator last, Compare comp);



}  // std
@@ -2321,7 +2321,7 @@ unique_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __res 
// reverse



template <class _BidirectionalIterator>

inline _LIBCPP_INLINE_VISIBILITY

inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17

void

__reverse(_BidirectionalIterator __first, _BidirectionalIterator __last, bidirectional_iterator_tag)

{
@@ -2335,7 +2335,7 @@ __reverse(_BidirectionalIterator __first, _BidirectionalIterator __last, bidirec 
}



template <class _RandomAccessIterator>

inline _LIBCPP_INLINE_VISIBILITY

inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17

void

__reverse(_RandomAccessIterator __first, _RandomAccessIterator __last, random_access_iterator_tag)

{
@@ -2345,7 +2345,7 @@ __reverse(_RandomAccessIterator __first, _RandomAccessIterator __last, random_ac 
}



template <class _BidirectionalIterator>

inline _LIBCPP_INLINE_VISIBILITY

inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17

void

reverse(_BidirectionalIterator __first, _BidirectionalIterator __last)

{
@@ -3393,7 +3393,7 @@ is_partitioned(_InputIterator __first, _InputIterator __last, _Predicate __pred) 
// partition



template <class _Predicate, class _ForwardIterator>

_ForwardIterator

_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator

__partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred, forward_iterator_tag)

{

    while (true)
@@ -3416,7 +3416,7 @@ __partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred 
}



template <class _Predicate, class _BidirectionalIterator>

_BidirectionalIterator

_LIBCPP_CONSTEXPR_AFTER_CXX17 _BidirectionalIterator

__partition(_BidirectionalIterator __first, _BidirectionalIterator __last, _Predicate __pred,

            bidirectional_iterator_tag)

{
@@ -3441,7 +3441,7 @@ __partition(_BidirectionalIterator __first, _BidirectionalIterator __last, _Pred 
}



template <class _ForwardIterator, class _Predicate>

inline _LIBCPP_INLINE_VISIBILITY

inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17

_ForwardIterator

partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred)

{
@@ -5760,7 +5760,7 @@ lexicographical_compare(_InputIterator1 __first1, _InputIterator1 __last1, 
// next_permutation



template <class _Compare, class _BidirectionalIterator>

bool

_LIBCPP_CONSTEXPR_AFTER_CXX17 bool

__next_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)

{

    _BidirectionalIterator __i = __last;
@@ -5787,7 +5787,7 @@ __next_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last 
}



template <class _BidirectionalIterator, class _Compare>

inline _LIBCPP_INLINE_VISIBILITY

inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17

bool

next_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)

{
@@ -5796,7 +5796,7 @@ next_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, 
}



template <class _BidirectionalIterator>

inline _LIBCPP_INLINE_VISIBILITY

inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17

bool

next_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last)

{
@@ -5807,7 +5807,7 @@ next_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last) 
// prev_permutation



template <class _Compare, class _BidirectionalIterator>

bool

_LIBCPP_CONSTEXPR_AFTER_CXX17 bool

__prev_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)

{

    _BidirectionalIterator __i = __last;
@@ -5834,7 +5834,7 @@ __prev_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last 
}



template <class _BidirectionalIterator, class _Compare>

inline _LIBCPP_INLINE_VISIBILITY

inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17

bool

prev_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)

{
@@ -5843,7 +5843,7 @@ prev_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, 
}



template <class _BidirectionalIterator>

inline _LIBCPP_INLINE_VISIBILITY

inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17

bool

prev_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last)

{

libcxx/test/std/algorithms/alg.modifying.operations/alg.partitions/partition.pass.cpp

+12 −4
Original line number Diff line number Diff line
@@ -11,7 +11,7 @@ 
// template<BidirectionalIterator Iter, Predicate<auto, Iter::value_type> Pred>

//   requires ShuffleIterator<Iter>

//         && CopyConstructible<Pred>

//   Iter

//   constexpr Iter  // constexpr in C++20

//   partition(Iter first, Iter last, Pred pred);



#include <algorithm>
@@ -23,11 +23,11 @@ 


struct is_odd

{

    bool operator()(const int& i) const {return i & 1;}

    TEST_CONSTEXPR bool operator()(const int& i) const {return i & 1;}

};



template <class Iter>

void

TEST_CONSTEXPR_CXX20 bool

test()

{

    // check mixed
@@ -92,6 +92,8 @@ test() 
        assert(is_odd()(*i));

    for (int* i = base(r); i < ia+sa; ++i)

        assert(!is_odd()(*i));



    return true;

}



int main(int, char**)
@@ -100,5 +102,11 @@ int main(int, char**) 
    test<random_access_iterator<int*> >();

    test<int*>();



#if TEST_STD_VER >= 20

    static_assert(test<bidirectional_iterator<int*>>());

    static_assert(test<random_access_iterator<int*>>());

    static_assert(test<int*>());

#endif



    return 0;

}

libcxx/test/std/algorithms/alg.modifying.operations/alg.reverse/reverse.pass.cpp

+11 −3
Original line number Diff line number Diff line
@@ -10,7 +10,7 @@ 


// template<BidirectionalIterator Iter>

//   requires HasSwap<Iter::reference, Iter::reference>

//   void

//   constexpr void  // constexpr in C++20

//   reverse(Iter first, Iter last);



#include <algorithm>
@@ -20,7 +20,7 @@ 
#include "test_iterators.h"



template <class Iter>

void

TEST_CONSTEXPR_CXX20 bool

test()

{

    int ia[] = {0};
@@ -50,6 +50,8 @@ test() 
    assert(id[1] == 2);

    assert(id[2] == 1);

    assert(id[3] == 0);



    return true;

}



int main(int, char**)
@@ -58,5 +60,11 @@ int main(int, char**) 
    test<random_access_iterator<int*> >();

    test<int*>();



#if TEST_STD_VER >= 20

    static_assert(test<bidirectional_iterator<int*>>());

    static_assert(test<random_access_iterator<int*>>());

    static_assert(test<int*>());

#endif



    return 0;

}

libcxx/test/std/algorithms/alg.sorting/alg.permutation.generators/next_permutation.pass.cpp

+11 −4
Original line number Diff line number Diff line
@@ -11,7 +11,7 @@ 
// template<BidirectionalIterator Iter>

//   requires ShuffleIterator<Iter>

//         && LessThanComparable<Iter::value_type>

//   bool

//   constexpr bool  // constexpr in C++20

//   next_permutation(Iter first, Iter last);



#include <algorithm>
@@ -22,7 +22,7 @@ 


#include <cstdio>



int factorial(int x)

TEST_CONSTEXPR_CXX14 int factorial(int x)

{

    int r = 1;

    for (; x; --x)
@@ -31,7 +31,7 @@ int factorial(int x) 
}



template <class Iter>

void

TEST_CONSTEXPR_CXX20 bool

test()

{

    int ia[] = {1, 2, 3, 4, 5, 6};
@@ -56,6 +56,7 @@ test() 
        } while (x);

        assert(count == factorial(e));

    }

    return true;

}



int main(int, char**)
@@ -64,5 +65,11 @@ int main(int, char**) 
    test<random_access_iterator<int*> >();

    test<int*>();



#if TEST_STD_VER >= 20

    static_assert(test<bidirectional_iterator<int*>>());

    static_assert(test<random_access_iterator<int*>>());

    static_assert(test<int*>());

#endif



    return 0;

}

libcxx/test/std/algorithms/alg.sorting/alg.permutation.generators/next_permutation_comp.pass.cpp

+11 −4
Original line number Diff line number Diff line
@@ -11,7 +11,7 @@ 
// template<BidirectionalIterator Iter, StrictWeakOrder<auto, Iter::value_type> Compare>

//   requires ShuffleIterator<Iter>

//         && CopyConstructible<Compare>

//   bool

//   constexpr bool  // constexpr in C++20

//   next_permutation(Iter first, Iter last, Compare comp);



#include <algorithm>
@@ -23,7 +23,7 @@ 


#include <cstdio>



int factorial(int x)

TEST_CONSTEXPR_CXX14 int factorial(int x)

{

    int r = 1;

    for (; x; --x)
@@ -32,7 +32,7 @@ int factorial(int x) 
}



template <class Iter>

void

TEST_CONSTEXPR_CXX20 bool

test()

{

    typedef std::greater<int> C;
@@ -58,6 +58,7 @@ test() 
        } while (x);

        assert(count == factorial(e));

    }

    return true;

}



int main(int, char**)
@@ -66,5 +67,11 @@ int main(int, char**) 
    test<random_access_iterator<int*> >();

    test<int*>();



#if TEST_STD_VER >= 20

    static_assert(test<bidirectional_iterator<int*>>());

    static_assert(test<random_access_iterator<int*>>());

    static_assert(test<int*>());

#endif



    return 0;

}