From 9e52541c8974f21f913664d742d74a4669c59879 Mon Sep 17 00:00:00 2001
From: isidorostsa <tsa.isidoros@gmail.com>
Date: Fri, 13 Oct 2023 12:59:58 +0300
Subject: [PATCH] fix returned value of in_out results

---
 .../algorithms/uninitialized_relocate.hpp     | 34 ++++++----
 .../uninitialized_relocate_n_primitive.hpp    | 65 ++++++++++---------
 2 files changed, 57 insertions(+), 42 deletions(-)

diff --git a/libs/core/algorithms/include/hpx/parallel/algorithms/uninitialized_relocate.hpp b/libs/core/algorithms/include/hpx/parallel/algorithms/uninitialized_relocate.hpp
index 1f8a858b6f53..ff43ff778a28 100644
--- a/libs/core/algorithms/include/hpx/parallel/algorithms/uninitialized_relocate.hpp
+++ b/libs/core/algorithms/include/hpx/parallel/algorithms/uninitialized_relocate.hpp
@@ -329,11 +329,13 @@ namespace hpx::parallel {
                         InIter part_source = get<0>(iters);
                         FwdIter part_dest = get<1>(iters);
 
-                        // returns (dest begin, dest end)
-                        return std::make_pair(part_dest,
+                        auto [part_source_advanced, part_dest_advanced] =
                             hpx::experimental::util::
                                 uninitialized_relocate_n_primitive(
-                                    part_source, part_size, part_dest));
+                                    part_source, part_size, part_dest);
+
+                        // returns (dest begin, dest end)
+                        return std::make_pair(part_dest, part_dest_advanced);
                     },
                     // finalize, called once if no error occurred
                     [first, dest, count](auto&& data) mutable
@@ -382,9 +384,12 @@ namespace hpx::parallel {
                     experimental::util::detail::relocation_traits<InIter,
                         FwdIter>::is_noexcept_relocatable_v)
             {
-                return util::in_out_result<InIter, FwdIter>{first,
+                auto [first_advanced, dest_advanced] =
                     hpx::experimental::util::uninitialized_relocate_n_primitive(
-                        first, count, dest)};
+                        first, count, dest);
+
+                return util::in_out_result<InIter, FwdIter>{
+                    first_advanced, dest_advanced};
             }
 
             // clang-format off
@@ -437,9 +442,11 @@ namespace hpx::parallel {
                 FwdIter dest) noexcept(hpx::experimental::util::detail::relocation_traits<
                     InIter1, FwdIter>::is_noexcept_relocatable_v)
             {
-                return util::in_out_result<InIter1, FwdIter>{first,
+                auto [first_advanced, dest_advanced] =
                     hpx::experimental::util::uninitialized_relocate_primitive(
-                        first, last, dest)};
+                        first, last, dest);
+
+                return util::in_out_result<InIter1, FwdIter>{first_advanced, dest_advanced};
             }
 
             template <typename ExPolicy, typename InIter1, typename InIter2,
@@ -485,8 +492,8 @@ namespace hpx::parallel {
             template <typename ExPolicy, typename BiIter1, typename BiIter2,
                 // clang-format off
                 HPX_CONCEPT_REQUIRES_(
-                    hpx::is_sequenced_execution_policy_v<ExPolicy>&&
-                    hpx::traits::is_bidirectional_iterator_v<BiIter1>&&
+                    hpx::is_sequenced_execution_policy_v<ExPolicy> &&
+                    hpx::traits::is_bidirectional_iterator_v<BiIter1> &&
                     hpx::traits::is_bidirectional_iterator_v<BiIter2>
                 )>
             //  clang-format on
@@ -495,9 +502,12 @@ namespace hpx::parallel {
                 BiIter2 dest_last) noexcept(hpx::experimental::util::detail::
                 relocation_traits<BiIter1, BiIter2>::is_noexcept_relocatable_v)
             {
-                return util::in_out_result<BiIter1, BiIter2>{first,
-                    hpx::experimental::util::uninitialized_relocate_backward_primitive(
-                        first, last, dest_last)};
+                auto [last_advanced, dest_last_advanced] = 
+                hpx::experimental::util::uninitialized_relocate_backward_primitive(
+                        first, last, dest_last);
+
+                return util::in_out_result<BiIter1, BiIter2>{last_advanced, dest_last_advanced
+                    };
             }
 
             template <typename ExPolicy, typename BiIter1, typename BiIter2,
diff --git a/libs/core/type_support/include/hpx/type_support/uninitialized_relocate_n_primitive.hpp b/libs/core/type_support/include/hpx/type_support/uninitialized_relocate_n_primitive.hpp
index 27def1b18fdd..c1894288b582 100644
--- a/libs/core/type_support/include/hpx/type_support/uninitialized_relocate_n_primitive.hpp
+++ b/libs/core/type_support/include/hpx/type_support/uninitialized_relocate_n_primitive.hpp
@@ -11,10 +11,12 @@
 #include <hpx/type_support/is_trivially_relocatable.hpp>
 #include <hpx/type_support/relocate_at.hpp>
 
-#include <cstring>
+#include <cstring>    // for memmove
 #include <type_traits>
 
-#if defined(__cpp_lib_trivially_relocatable)
+#include <tuple>
+
+#if defined(HPX_HAVE_P1144_RELOCATE_AT)
 #include <memory>
 #endif
 
@@ -84,7 +86,7 @@ namespace hpx::experimental::util {
         // uninitialized_relocate_n //
         //////////////////////////////
         template <typename InIter, typename Size, typename FwdIter>
-        FwdIter uninitialized_relocate_n_primitive_helper(
+        std::tuple<InIter, FwdIter> uninitialized_relocate_n_primitive_helper(
             InIter first, Size n, FwdIter dst, buffer_memcpy_tag) noexcept
         {
             if (n != 0)
@@ -106,13 +108,13 @@ namespace hpx::experimental::util {
                 dst += n;
             }
 
-            return dst;
+            return {first, dst};
         }
 
         template <typename InIter, typename Size, typename FwdIter>
         // Either the buffer is not contiguous or the types are no-throw
         // move constructible but not trivially relocatable
-        FwdIter uninitialized_relocate_n_primitive_helper(
+        std::tuple<InIter, FwdIter> uninitialized_relocate_n_primitive_helper(
             InIter first, Size n, FwdIter dst, for_loop_nothrow_tag) noexcept
         {
             for (Size i = 0; i < n; ++first, ++dst, ++i)
@@ -123,11 +125,11 @@ namespace hpx::experimental::util {
                     std::addressof(*first), std::addressof(*dst));
             }
 
-            return dst;
+            return {first, dst};
         }
 
         template <typename InIter, typename Size, typename FwdIter>
-        FwdIter uninitialized_relocate_n_primitive_helper(
+        std::tuple<InIter, FwdIter> uninitialized_relocate_n_primitive_helper(
             InIter first, Size n, FwdIter dst, for_loop_try_catch_tag)
         {
             FwdIter original_dst = dst;
@@ -158,14 +160,14 @@ namespace hpx::experimental::util {
                 }
             }
 
-            return dst;
+            return {first, dst};
         }
 
         ////////////////////////////
         // uninitialized_relocate //
         ////////////////////////////
         template <typename InIter, typename Sent, typename FwdIter>
-        FwdIter uninitialized_relocate_primitive_helper(
+        std::tuple<InIter, FwdIter> uninitialized_relocate_primitive_helper(
             InIter first, Sent last, FwdIter dst, buffer_memcpy_tag) noexcept
         {
             return uninitialized_relocate_n_primitive_helper(
@@ -175,7 +177,7 @@ namespace hpx::experimental::util {
         template <typename InIter, typename Sent, typename FwdIter>
         // Either the buffer is not contiguous or the types are no-throw
         // move constructible but not trivially relocatable
-        FwdIter uninitialized_relocate_primitive_helper(
+        std::tuple<InIter, FwdIter> uninitialized_relocate_primitive_helper(
             InIter first, Sent last, FwdIter dst, for_loop_nothrow_tag) noexcept
         {
             for (; first != last; ++first, ++dst)
@@ -186,11 +188,11 @@ namespace hpx::experimental::util {
                     std::addressof(*first), std::addressof(*dst));
             }
 
-            return dst;
+            return {first, dst};
         }
 
         template <typename InIter, typename Sent, typename FwdIter>
-        FwdIter uninitialized_relocate_primitive_helper(
+        std::tuple<InIter, FwdIter> uninitialized_relocate_primitive_helper(
             InIter first, Sent last, FwdIter dst, for_loop_try_catch_tag)
         {
             FwdIter original_dst = dst;
@@ -218,14 +220,15 @@ namespace hpx::experimental::util {
                 }
             }
 
-            return dst;
+            return {first, dst};
         }
 
         /////////////////////////////////////
         // uninitialized_relocate_backward //
         /////////////////////////////////////
         template <typename BiIter1, typename BiIter2>
-        BiIter2 uninitialized_relocate_backward_primitive_helper(BiIter1 first,
+        std::tuple<BiIter1, BiIter2>
+        uninitialized_relocate_backward_primitive_helper(BiIter1 first,
             BiIter1 last, BiIter2 dst_last, buffer_memcpy_tag) noexcept
         {
             // Here we know the iterators are contiguous
@@ -242,7 +245,8 @@ namespace hpx::experimental::util {
         // Either the buffer is not contiguous or the types are no-throw
         // move constructible but not trivially relocatable
         // dst_last is one past the last element of the destination
-        BiIter2 uninitialized_relocate_backward_primitive_helper(BiIter1 first,
+        std::tuple<BiIter1, BiIter2>
+        uninitialized_relocate_backward_primitive_helper(BiIter1 first,
             BiIter1 last, BiIter2 dst_last, for_loop_nothrow_tag) noexcept
         {
             while (first != last)
@@ -255,14 +259,15 @@ namespace hpx::experimental::util {
                     std::addressof(*last), std::addressof(*dst_last));
             }
 
-            return dst_last;
+            return {last, dst_last};
         }
 
-        template <typename InIter, typename Sent, typename FwdIter>
-        FwdIter uninitialized_relocate_backward_primitive_helper(
-            InIter first, Sent last, FwdIter dst_last, for_loop_try_catch_tag)
+        template <typename BiIter1, typename BiIter2>
+        std::tuple<BiIter1, BiIter2>
+        uninitialized_relocate_backward_primitive_helper(BiIter1 first,
+            BiIter1 last, BiIter2 dst_last, for_loop_try_catch_tag)
         {
-            FwdIter original_dst_last = dst_last;
+            BiIter2 original_dst_last = dst_last;
 
             while (first != last)
             {
@@ -289,7 +294,7 @@ namespace hpx::experimental::util {
                 }
             }
 
-            return dst_last;
+            return {last, dst_last};
         }
 
     }    // namespace detail
@@ -300,7 +305,7 @@ namespace hpx::experimental::util {
     template <typename InIter, typename FwdIter, typename Size,
         typename iterators_are_contiguous_t>
     // clang-format off
-    FwdIter uninitialized_relocate_n_primitive(InIter first, Size n,
+    std::tuple<InIter, FwdIter> uninitialized_relocate_n_primitive(InIter first, Size n,
         FwdIter dst, iterators_are_contiguous_t) noexcept(
             detail::relocation_traits<InIter, FwdIter>::is_noexcept_relocatable_v)
     // clang-format on
@@ -317,8 +322,8 @@ namespace hpx::experimental::util {
     }
 
     template <typename InIter, typename Size, typename FwdIter>
-    FwdIter uninitialized_relocate_n_primitive(InIter first, Size n,
-        FwdIter dst) noexcept(detail::relocation_traits<InIter,
+    std::tuple<InIter, FwdIter> uninitialized_relocate_n_primitive(InIter first,
+        Size n, FwdIter dst) noexcept(detail::relocation_traits<InIter,
         FwdIter>::is_noexcept_relocatable_v)
     {
         using iterators_are_contiguous_default_t =
@@ -335,7 +340,7 @@ namespace hpx::experimental::util {
     template <typename InIter, typename Sent, typename FwdIter,
         typename iterators_are_contiguous_t>
     // clang-format off
-    FwdIter uninitialized_relocate_primitive(InIter first, Sent last,
+    std::tuple<InIter, FwdIter> uninitialized_relocate_primitive(InIter first, Sent last,
         FwdIter dst, iterators_are_contiguous_t) noexcept(
             detail::relocation_traits<InIter, FwdIter>::is_noexcept_relocatable_v)
     // clang-format on
@@ -353,8 +358,8 @@ namespace hpx::experimental::util {
     }
 
     template <typename InIter, typename Sent, typename FwdIter>
-    FwdIter uninitialized_relocate_primitive(InIter first, Sent last,
-        FwdIter dst) noexcept(detail::relocation_traits<InIter,
+    std::tuple<InIter, FwdIter> uninitialized_relocate_primitive(InIter first,
+        Sent last, FwdIter dst) noexcept(detail::relocation_traits<InIter,
         FwdIter>::is_noexcept_relocatable_v)
     {
         using iterators_are_contiguous_default_t =
@@ -371,7 +376,7 @@ namespace hpx::experimental::util {
     template <typename BiIter1, typename BiIter2,
         typename iterators_are_contiguous_t>
     // clang-format off
-    BiIter2 uninitialized_relocate_backward_primitive(BiIter1 first, BiIter1 last,
+    std::tuple<BiIter1, BiIter2> uninitialized_relocate_backward_primitive(BiIter1 first, BiIter1 last,
         BiIter2 dst_last, iterators_are_contiguous_t) noexcept(
             detail::relocation_traits<BiIter1, BiIter2>::is_noexcept_relocatable_v)
     // clang-format on
@@ -389,8 +394,8 @@ namespace hpx::experimental::util {
     }
 
     template <typename BiIter1, typename BiIter2>
-    BiIter2 uninitialized_relocate_backward_primitive(BiIter1 first,
-        BiIter1 last,
+    std::tuple<BiIter1, BiIter2> uninitialized_relocate_backward_primitive(
+        BiIter1 first, BiIter1 last,
         BiIter2 dst_last) noexcept(detail::relocation_traits<BiIter1,
         BiIter2>::is_noexcept_relocatable_v)
     {