1 files changed, 50 insertions, 23 deletions

diff --git a/contrib/llvm-project/libcxx/include/__algorithm/ranges_unique_copy.h b/contrib/llvm-project/libcxx/include/__algorithm/ranges_unique_copy.h
index 56361aa8ae2f..8c0b970d043f 100644
--- a/contrib/llvm-project/libcxx/include/__algorithm/ranges_unique_copy.h
+++ b/contrib/llvm-project/libcxx/include/__algorithm/ranges_unique_copy.h
@@ -10,6 +10,7 @@
 #define _LIBCPP___ALGORITHM_RANGES_UNIQUE_COPY_H
 
 #include <__algorithm/in_out_result.h>
+#include <__algorithm/iterator_operations.h>
 #include <__algorithm/make_projected.h>
 #include <__algorithm/unique_copy.h>
 #include <__concepts/same_as.h>
@@ -19,8 +20,8 @@
 #include <__functional/ranges_operations.h>
 #include <__iterator/concepts.h>
 #include <__iterator/iterator_traits.h>
-#include <__iterator/readable_traits.h>
 #include <__iterator/projected.h>
+#include <__iterator/readable_traits.h>
 #include <__ranges/access.h>
 #include <__ranges/concepts.h>
 #include <__ranges/dangling.h>
@@ -42,42 +43,68 @@ using unique_copy_result = in_out_result<_InIter, _OutIter>;
 
 namespace __unique_copy {
 
+template <class _InIter, class _OutIter>
+concept __can_reread_from_output = (input_iterator<_OutIter> && same_as<iter_value_t<_InIter>, iter_value_t<_OutIter>>);
+
 struct __fn {
+  template <class _InIter, class _OutIter>
+  static consteval auto __get_algo_tag() {
+    if constexpr (forward_iterator<_InIter>) {
+      return __unique_copy_tags::__reread_from_input_tag{};
+    } else if constexpr (__can_reread_from_output<_InIter, _OutIter>) {
+      return __unique_copy_tags::__reread_from_output_tag{};
+    } else if constexpr (indirectly_copyable_storable<_InIter, _OutIter>) {
+      return __unique_copy_tags::__read_from_tmp_value_tag{};
+    }
+  }
+
+  template <class _InIter, class _OutIter>
+  using __algo_tag_t = decltype(__get_algo_tag<_InIter, _OutIter>());
 
-  template <input_iterator _InIter, sentinel_for<_InIter> _Sent, weakly_incrementable _OutIter, class _Proj = identity,
+  template <input_iterator _InIter,
+            sentinel_for<_InIter> _Sent,
+            weakly_incrementable _OutIter,
+            class _Proj                                                    = identity,
             indirect_equivalence_relation<projected<_InIter, _Proj>> _Comp = ranges::equal_to>
-  requires indirectly_copyable<_InIter, _OutIter> &&
-            (forward_iterator<_InIter> ||
-            (input_iterator<_OutIter> && same_as<iter_value_t<_InIter>, iter_value_t<_OutIter>>) ||
-            indirectly_copyable_storable<_InIter, _OutIter>)
-  _LIBCPP_HIDE_FROM_ABI constexpr
-  unique_copy_result<_InIter, _OutIter>
+    requires indirectly_copyable<_InIter, _OutIter> &&
+             (forward_iterator<_InIter> ||
+              (input_iterator<_OutIter> && same_as<iter_value_t<_InIter>, iter_value_t<_OutIter>>) ||
+              indirectly_copyable_storable<_InIter, _OutIter>)
+  _LIBCPP_HIDE_FROM_ABI constexpr unique_copy_result<_InIter, _OutIter>
   operator()(_InIter __first, _Sent __last, _OutIter __result, _Comp __comp = {}, _Proj __proj = {}) const {
-    // TODO: implement
-    (void)__first; (void)__last; (void)__result; (void)__comp; (void)__proj;
-    return {};
+    auto __ret = std::__unique_copy<_RangeAlgPolicy>(
+        std::move(__first),
+        std::move(__last),
+        std::move(__result),
+        std::__make_projected(__comp, __proj),
+        __algo_tag_t<_InIter, _OutIter>());
+    return {std::move(__ret.first), std::move(__ret.second)};
   }
 
-  template <input_range _Range, weakly_incrementable _OutIter, class _Proj = identity,
+  template <input_range _Range,
+            weakly_incrementable _OutIter,
+            class _Proj                                                               = identity,
             indirect_equivalence_relation<projected<iterator_t<_Range>, _Proj>> _Comp = ranges::equal_to>
-  requires indirectly_copyable<iterator_t<_Range>, _OutIter> &&
-            (forward_iterator<iterator_t<_Range>> ||
-            (input_iterator<_OutIter> && same_as<range_value_t<_Range>, iter_value_t<_OutIter>>) ||
-            indirectly_copyable_storable<iterator_t<_Range>, _OutIter>)
-  _LIBCPP_HIDE_FROM_ABI constexpr
-  unique_copy_result<borrowed_iterator_t<_Range>, _OutIter>
+    requires indirectly_copyable<iterator_t<_Range>, _OutIter> &&
+      (forward_iterator<iterator_t<_Range>> ||
+       (input_iterator<_OutIter> && same_as<range_value_t<_Range>, iter_value_t<_OutIter>>) ||
+       indirectly_copyable_storable<iterator_t<_Range>, _OutIter>)
+  _LIBCPP_HIDE_FROM_ABI constexpr unique_copy_result<borrowed_iterator_t<_Range>, _OutIter>
   operator()(_Range&& __range, _OutIter __result, _Comp __comp = {}, _Proj __proj = {}) const {
-    // TODO: implement
-    (void)__range; (void)__result; (void)__comp; (void)__proj;
-    return {};
+    auto __ret = std::__unique_copy<_RangeAlgPolicy>(
+        ranges::begin(__range),
+        ranges::end(__range),
+        std::move(__result),
+        std::__make_projected(__comp, __proj),
+        __algo_tag_t<iterator_t<_Range>, _OutIter>());
+    return {std::move(__ret.first), std::move(__ret.second)};
   }
-
 };
 
 } // namespace __unique_copy
 
 inline namespace __cpo {
-  inline constexpr auto unique_copy = __unique_copy::__fn{};
+inline constexpr auto unique_copy = __unique_copy::__fn{};
 } // namespace __cpo
 } // namespace ranges