Fix PR#25973 : 'basic_string::assign(InputIt, InputIt) doesn't provide the strong exception safety guarantee'. This turned out to be a pervasive problem in <string>, which required a fair amount of rework. Add in an optimization for when iterators provide noexcept increment/comparison/assignment/dereference (which covers many of the iterators in libc++). Reviewed as http://reviews.llvm.org/D15862
llvm-svn: 257682
Cr-Mirrored-From: sso://chromium.googlesource.com/_direct/external/github.com/llvm/llvm-project
Cr-Mirrored-Commit: 76b4afc04051298081c2f46056138b4013c2f49d
diff --git a/include/iterator b/include/iterator
index 8dd6bd5..8d9b311 100644
--- a/include/iterator
+++ b/include/iterator
@@ -437,6 +437,12 @@
template <class _Tp>
struct __is_random_access_iterator : public __has_iterator_category_convertible_to<_Tp, random_access_iterator_tag> {};
+template <class _Tp>
+struct __is_exactly_input_iterator
+ : public integral_constant<bool,
+ __has_iterator_category_convertible_to<_Tp, input_iterator_tag>::value &&
+ !__has_iterator_category_convertible_to<_Tp, forward_iterator_tag>::value> {};
+
template<class _Category, class _Tp, class _Distance = ptrdiff_t,
class _Pointer = _Tp*, class _Reference = _Tp&>
struct _LIBCPP_TYPE_VIS_ONLY iterator
@@ -1404,6 +1410,23 @@
return __x;
}
+template <class _Iter>
+struct __libcpp_is_trivial_iterator
+ : public _LIBCPP_BOOL_CONSTANT(is_pointer<_Iter>::value) {};
+
+template <class _Iter>
+struct __libcpp_is_trivial_iterator<move_iterator<_Iter> >
+ : public _LIBCPP_BOOL_CONSTANT(__libcpp_is_trivial_iterator<_Iter>::value) {};
+
+template <class _Iter>
+struct __libcpp_is_trivial_iterator<reverse_iterator<_Iter> >
+ : public _LIBCPP_BOOL_CONSTANT(__libcpp_is_trivial_iterator<_Iter>::value) {};
+
+template <class _Iter>
+struct __libcpp_is_trivial_iterator<__wrap_iter<_Iter> >
+ : public _LIBCPP_BOOL_CONSTANT(__libcpp_is_trivial_iterator<_Iter>::value) {};
+
+
template <class _Tp, size_t _Np>
inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
_Tp*