Implement constexpr support for reverse_iterator. Reviewed as https://reviews.llvm.org/D25534
llvm-svn: 284602
Cr-Mirrored-From: sso://chromium.googlesource.com/_direct/external/github.com/llvm/llvm-project
Cr-Mirrored-Commit: 1b8f260ed943e86023a1362ee5b45ff717d246d0
diff --git a/include/iterator b/include/iterator
index b0f5527..731791b 100644
--- a/include/iterator
+++ b/include/iterator
@@ -89,57 +89,60 @@
typedef typename iterator_traits<Iterator>::reference reference;
typedef typename iterator_traits<Iterator>::pointer pointer;
- reverse_iterator();
- explicit reverse_iterator(Iterator x);
- template <class U> reverse_iterator(const reverse_iterator<U>& u);
- Iterator base() const;
- reference operator*() const;
- pointer operator->() const;
- reverse_iterator& operator++();
- reverse_iterator operator++(int);
- reverse_iterator& operator--();
- reverse_iterator operator--(int);
- reverse_iterator operator+ (difference_type n) const;
- reverse_iterator& operator+=(difference_type n);
- reverse_iterator operator- (difference_type n) const;
- reverse_iterator& operator-=(difference_type n);
- reference operator[](difference_type n) const;
+ constexpr reverse_iterator();
+ constexpr explicit reverse_iterator(Iterator x);
+ template <class U> constexpr reverse_iterator(const reverse_iterator<U>& u);
+ template <class U> constexpr reverse_iterator& operator=(const reverse_iterator<U>& u);
+ constexpr Iterator base() const;
+ constexpr reference operator*() const;
+ constexpr pointer operator->() const;
+ constexpr reverse_iterator& operator++();
+ constexpr reverse_iterator operator++(int);
+ constexpr reverse_iterator& operator--();
+ constexpr reverse_iterator operator--(int);
+ constexpr reverse_iterator operator+ (difference_type n) const;
+ constexpr reverse_iterator& operator+=(difference_type n);
+ constexpr reverse_iterator operator- (difference_type n) const;
+ constexpr reverse_iterator& operator-=(difference_type n);
+ constexpr reference operator[](difference_type n) const;
};
template <class Iterator1, class Iterator2>
-bool
+constexpr bool // constexpr in C++17
operator==(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
template <class Iterator1, class Iterator2>
-bool
+constexpr bool // constexpr in C++17
operator<(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
template <class Iterator1, class Iterator2>
-bool
+constexpr bool // constexpr in C++17
operator!=(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
template <class Iterator1, class Iterator2>
-bool
+constexpr bool // constexpr in C++17
operator>(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
template <class Iterator1, class Iterator2>
-bool
+constexpr bool // constexpr in C++17
operator>=(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
template <class Iterator1, class Iterator2>
-bool
+constexpr bool // constexpr in C++17
operator<=(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
template <class Iterator1, class Iterator2>
-auto
+constexpr auto
operator-(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y)
--> decltype(__y.base() - __x.base());
+-> decltype(__y.base() - __x.base()); // constexpr in C++17
template <class Iterator>
-reverse_iterator<Iterator>
-operator+(typename reverse_iterator<Iterator>::difference_type n, const reverse_iterator<Iterator>& x);
+constexpr reverse_iterator<Iterator>
+operator+(typename reverse_iterator<Iterator>::difference_type n,
+ const reverse_iterator<Iterator>& x); // constexpr in C++17
-template <class Iterator> reverse_iterator<Iterator> make_reverse_iterator(Iterator i); // C++14
+template <class Iterator>
+constexpr reverse_iterator<Iterator> make_reverse_iterator(Iterator i); // C++14, constexpr in C++17
template <class Container>
class back_insert_iterator
@@ -618,7 +621,7 @@
typename iterator_traits<_Iter>::reference>
{
private:
- mutable _Iter __t; // no longer used as of LWG #2360, not removed due to ABI break
+ /*mutable*/ _Iter __t; // no longer used as of LWG #2360, not removed due to ABI break
protected:
_Iter current;
public:
@@ -627,33 +630,45 @@
typedef typename iterator_traits<_Iter>::reference reference;
typedef typename iterator_traits<_Iter>::pointer pointer;
- _LIBCPP_INLINE_VISIBILITY reverse_iterator() : current() {}
- _LIBCPP_INLINE_VISIBILITY explicit reverse_iterator(_Iter __x) : __t(__x), current(__x) {}
- template <class _Up> _LIBCPP_INLINE_VISIBILITY reverse_iterator(const reverse_iterator<_Up>& __u)
- : __t(__u.base()), current(__u.base()) {}
- _LIBCPP_INLINE_VISIBILITY _Iter base() const {return current;}
- _LIBCPP_INLINE_VISIBILITY reference operator*() const {_Iter __tmp = current; return *--__tmp;}
- _LIBCPP_INLINE_VISIBILITY pointer operator->() const {return _VSTD::addressof(operator*());}
- _LIBCPP_INLINE_VISIBILITY reverse_iterator& operator++() {--current; return *this;}
- _LIBCPP_INLINE_VISIBILITY reverse_iterator operator++(int)
- {reverse_iterator __tmp(*this); --current; return __tmp;}
- _LIBCPP_INLINE_VISIBILITY reverse_iterator& operator--() {++current; return *this;}
- _LIBCPP_INLINE_VISIBILITY reverse_iterator operator--(int)
- {reverse_iterator __tmp(*this); ++current; return __tmp;}
- _LIBCPP_INLINE_VISIBILITY reverse_iterator operator+ (difference_type __n) const
- {return reverse_iterator(current - __n);}
- _LIBCPP_INLINE_VISIBILITY reverse_iterator& operator+=(difference_type __n)
- {current -= __n; return *this;}
- _LIBCPP_INLINE_VISIBILITY reverse_iterator operator- (difference_type __n) const
- {return reverse_iterator(current + __n);}
- _LIBCPP_INLINE_VISIBILITY reverse_iterator& operator-=(difference_type __n)
- {current += __n; return *this;}
- _LIBCPP_INLINE_VISIBILITY reference operator[](difference_type __n) const
- {return *(*this + __n);}
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+ reverse_iterator() : __t(), current() {}
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+ explicit reverse_iterator(_Iter __x) : __t(__x), current(__x) {}
+ template <class _Up>
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+ reverse_iterator(const reverse_iterator<_Up>& __u) : __t(__u.base()), current(__u.base()) {}
+ template <class _Up>
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+ reverse_iterator& operator=(const reverse_iterator<_Up>& __u)
+ { __t = current = __u.base(); return *this; }
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+ _Iter base() const {return current;}
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+ reference operator*() const {_Iter __tmp = current; return *--__tmp;}
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+ pointer operator->() const {return _VSTD::addressof(operator*());}
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+ reverse_iterator& operator++() {--current; return *this;}
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+ reverse_iterator operator++(int) {reverse_iterator __tmp(*this); --current; return __tmp;}
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+ reverse_iterator& operator--() {++current; return *this;}
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+ reverse_iterator operator--(int) {reverse_iterator __tmp(*this); ++current; return __tmp;}
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+ reverse_iterator operator+ (difference_type __n) const {return reverse_iterator(current - __n);}
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+ reverse_iterator& operator+=(difference_type __n) {current -= __n; return *this;}
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+ reverse_iterator operator- (difference_type __n) const {return reverse_iterator(current + __n);}
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+ reverse_iterator& operator-=(difference_type __n) {current += __n; return *this;}
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+ reference operator[](difference_type __n) const {return *(*this + __n);}
};
template <class _Iter1, class _Iter2>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
bool
operator==(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
{
@@ -661,7 +676,7 @@
}
template <class _Iter1, class _Iter2>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
bool
operator<(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
{
@@ -669,7 +684,7 @@
}
template <class _Iter1, class _Iter2>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
bool
operator!=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
{
@@ -677,7 +692,7 @@
}
template <class _Iter1, class _Iter2>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
bool
operator>(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
{
@@ -685,7 +700,7 @@
}
template <class _Iter1, class _Iter2>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
bool
operator>=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
{
@@ -693,7 +708,7 @@
}
template <class _Iter1, class _Iter2>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
bool
operator<=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
{
@@ -702,7 +717,7 @@
#ifndef _LIBCPP_CXX03_LANG
template <class _Iter1, class _Iter2>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
auto
operator-(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
-> decltype(__y.base() - __x.base())
@@ -720,7 +735,7 @@
#endif
template <class _Iter>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
reverse_iterator<_Iter>
operator+(typename reverse_iterator<_Iter>::difference_type __n, const reverse_iterator<_Iter>& __x)
{
@@ -729,7 +744,7 @@
#if _LIBCPP_STD_VER > 11
template <class _Iter>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
reverse_iterator<_Iter> make_reverse_iterator(_Iter __i)
{
return reverse_iterator<_Iter>(__i);