diff options
Diffstat (limited to 'libcxx/include/__algorithm/unwrap_iter.h')
| -rw-r--r-- | libcxx/include/__algorithm/unwrap_iter.h | 21 |
1 files changed, 16 insertions, 5 deletions
diff --git a/libcxx/include/__algorithm/unwrap_iter.h b/libcxx/include/__algorithm/unwrap_iter.h index 0f661e10a74d..91346e3c1bd2 100644 --- a/libcxx/include/__algorithm/unwrap_iter.h +++ b/libcxx/include/__algorithm/unwrap_iter.h @@ -21,24 +21,27 @@ # pragma GCC system_header #endif +_LIBCPP_PUSH_MACROS +#include <__undef_macros> + _LIBCPP_BEGIN_NAMESPACE_STD // TODO: Change the name of __unwrap_iter_impl to something more appropriate // The job of __unwrap_iter is to remove iterator wrappers (like reverse_iterator or __wrap_iter), // to reduce the number of template instantiations and to enable pointer-based optimizations e.g. in std::copy. -// In debug mode, we don't do this. // // Some algorithms (e.g. std::copy, but not std::sort) need to convert an // "unwrapped" result back into the original iterator type. Doing that is the job of __rewrap_iter. // Default case - we can't unwrap anything -template <class _Iter, bool = __is_cpp17_contiguous_iterator<_Iter>::value> +template <class _Iter, bool = __libcpp_is_contiguous_iterator<_Iter>::value> struct __unwrap_iter_impl { static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Iter __rewrap(_Iter, _Iter __iter) { return __iter; } static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Iter __unwrap(_Iter __i) _NOEXCEPT { return __i; } }; -#ifndef _LIBCPP_ENABLE_DEBUG_MODE +// TODO(hardening): make sure that the following unwrapping doesn't unexpectedly turn hardened iterators into raw +// pointers. // It's a contiguous iterator, so we can use a raw pointer instead template <class _Iter> @@ -54,8 +57,6 @@ struct __unwrap_iter_impl<_Iter, true> { } }; -#endif // !_LIBCPP_ENABLE_DEBUG_MODE - template<class _Iter, class _Impl = __unwrap_iter_impl<_Iter>, __enable_if_t<is_copy_constructible<_Iter>::value, int> = 0> @@ -64,6 +65,14 @@ decltype(_Impl::__unwrap(std::declval<_Iter>())) __unwrap_iter(_Iter __i) _NOEXC return _Impl::__unwrap(__i); } +// Allow input_iterators to be passed to __unwrap_iter (but not __rewrap_iter) +#if _LIBCPP_STD_VER >= 20 +template <class _Iter, __enable_if_t<!is_copy_constructible<_Iter>::value, int> = 0> +inline _LIBCPP_HIDE_FROM_ABI constexpr _Iter __unwrap_iter(_Iter __i) noexcept { + return __i; +} +#endif + template <class _OrigIter, class _Iter, class _Impl = __unwrap_iter_impl<_OrigIter> > _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _OrigIter __rewrap_iter(_OrigIter __orig_iter, _Iter __iter) _NOEXCEPT { return _Impl::__rewrap(std::move(__orig_iter), std::move(__iter)); @@ -71,4 +80,6 @@ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _OrigIter __rewrap_iter(_OrigIter __orig _LIBCPP_END_NAMESPACE_STD +_LIBCPP_PUSH_MACROS + #endif // _LIBCPP___ALGORITHM_UNWRAP_ITER_H |