P0429R9 <flat_map> and P1222R4 <flat_set>

benchmarks/CMakeLists.txt

@@ -111,6 +111,7 @@ add_benchmark(filesystem src/filesystem.cpp)
 add_benchmark(fill src/fill.cpp)
 add_benchmark(find_and_count src/find_and_count.cpp)
 add_benchmark(find_first_of src/find_first_of.cpp)
+add_benchmark(flat_meow_assign src/flat_meow_assign.cpp)
 add_benchmark(has_single_bit src/has_single_bit.cpp)
 add_benchmark(includes src/includes.cpp)
 add_benchmark(integer_to_string src/integer_to_string.cpp)

benchmarks/src/flat_meow_assign.cpp

@@ -0,0 +1,52 @@
+// Copyright (c) Microsoft Corporation.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+#include <benchmark/benchmark.h>
+#include <flat_map>
+#include <flat_set>
+#include <string>
+
+using namespace std;
+
+void flat_map_strings(benchmark::State& state) {
+    flat_map<string, int> pieces;
+    for (auto _ : state) {
+        pieces = {{"soldier"s, 1}, {"soldier"s, 2}, {"soldier"s, 3}, {"soldier"s, 4}, {"soldier"s, 5}, {"soldier"s, 6},
+            {"soldier"s, 7}, {"soldier"s, 8}, {"tower"s, 9}, {"horse"s, 10}, {"elephant"s, 11}, {"vizier"s, 12},
+            {"king"s, 13}, {"elephant"s, 14}, {"horse"s, 15}, {"tower"s, 16}};
+        benchmark::DoNotOptimize(pieces);
+    }
+}
+
+void flat_set_strings(benchmark::State& state) {
+    flat_set<string> pieces;
+    for (auto _ : state) {
+        pieces = {"soldier"s, "soldier"s, "soldier"s, "soldier"s, "soldier"s, "soldier"s, "soldier"s, "soldier"s,
+            "tower"s, "horse"s, "elephant"s, "vizier"s, "king"s, "elephant"s, "horse"s, "tower"s};
+        benchmark::DoNotOptimize(pieces);
+    }
+}
+
+void flat_map_integers(benchmark::State& state) {
+    flat_map<int, int> pieces;
+    for (auto _ : state) {
+        pieces = {{'s', 1}, {'s', 2}, {'s', 3}, {'s', 4}, {'s', 5}, {'s', 6}, {'s', 7}, {'s', 8}, {'T', 9}, {'H', 10},
+            {'E', 11}, {'V', 12}, {'K', 13}, {'E', 14}, {'H', 15}, {'T', 16}};
+        benchmark::DoNotOptimize(pieces);
+    }
+}
+
+void flat_set_integers(benchmark::State& state) {
+    flat_set<int> pieces;
+    for (auto _ : state) {
+        pieces = {'s', 's', 's', 's', 's', 's', 's', 's', 'T', 'H', 'E', 'V', 'K', 'E', 'H', 'T'};
+        benchmark::DoNotOptimize(pieces);
+    }
+}
+
+BENCHMARK(flat_map_strings);
+BENCHMARK(flat_set_strings);
+BENCHMARK(flat_map_integers);
+BENCHMARK(flat_set_integers);
+
+BENCHMARK_MAIN();

stl/CMakeLists.txt

@@ -76,6 +76,8 @@ set(HEADERS
     ${CMAKE_CURRENT_LIST_DIR}/inc/experimental/generator
     ${CMAKE_CURRENT_LIST_DIR}/inc/experimental/resumable
     ${CMAKE_CURRENT_LIST_DIR}/inc/filesystem
+    ${CMAKE_CURRENT_LIST_DIR}/inc/flat_map
+    ${CMAKE_CURRENT_LIST_DIR}/inc/flat_set
     ${CMAKE_CURRENT_LIST_DIR}/inc/format
     ${CMAKE_CURRENT_LIST_DIR}/inc/forward_list
     ${CMAKE_CURRENT_LIST_DIR}/inc/fstream

stl/debugger/STL.natvis

@@ -1035,13 +1035,13 @@ SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
       </Expand>
   </Type>
 
-  <!-- VC 2015 -->
   <Type Name="std::deque&lt;*&gt;">
-      <DisplayString>{{ size={_Mypair._Myval2._Mysize} }}</DisplayString>
+      <Intrinsic Name="size" Expression="_Mypair._Myval2._Mysize" />
+      <DisplayString>{{ size={size()} }}</DisplayString>
       <Expand>
           <Item Name="[allocator]" ExcludeView="simple">_Mypair</Item>
           <IndexListItems>
-              <Size>_Mypair._Myval2._Mysize</Size>
+              <Size>size()</Size>
               <ValueNode>_Mypair._Myval2._Map[(($i + _Mypair._Myval2._Myoff) / _EEN_DS) % _Mypair._Myval2._Mapsize][($i + _Mypair._Myval2._Myoff) % _EEN_DS]</ValueNode>
           </IndexListItems>
       </Expand>
@@ -2256,4 +2256,59 @@ SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
     </Expand>
   </Type>
 
+  <Type Name="std::flat_map&lt;*&gt;">
+   <AlternativeType Name="std::flat_multimap&lt;*&gt;"/>
+    <Intrinsic Name="size" Expression="_Data.keys.size()"/>
+    <Intrinsic Name="key_at" Expression="&amp;_Data.keys[index]">
+      <Parameter Name="index" Type="size_t" />
+    </Intrinsic>
+    <Intrinsic Name="value_at" Expression="&amp;_Data.values[index]">
+      <Parameter Name="index" Type="size_t" />
+    </Intrinsic>
+
+    <DisplayString>{{ size={size()} }}</DisplayString>
+
+    <Expand>
+      <Item Name="[size]">size()</Item>
+      <Item Name="[comparator]" ExcludeView="simple">_Key_compare</Item>
+      <CustomListItems>
+        <Variable Name="i" InitialValue="0" />
+        <Size>size()</Size>
+        <Loop>
+          <Item Name="[{*key_at(i)}]">*value_at(i)</Item>
+          <Exec>++i</Exec>
+        </Loop>
+      </CustomListItems>
+    </Expand>
+  </Type>
+
+  <!-- fallback when the primary visualization (above) fails to parse, e.g. some custom containers -->
+  <Type Name="std::flat_map&lt;*&gt;" Priority="MediumLow">
+    <AlternativeType Name="std::flat_multimap&lt;*&gt;"/>
+    <Intrinsic Name="size" Expression="_Data.keys.size()"/>
+    <DisplayString>{{ size={size()} }}</DisplayString>
+    <Expand>
+      <Item Name="[comparator]" ExcludeView="simple">_Key_compare</Item>
+      <Item Name="[keys]">_Data.keys</Item>
+      <Item Name="[values]">_Data.values</Item>
+    </Expand>
+  </Type>
+
+  <Type Name="std::_Pairing_iterator_provider&lt;*&gt;::_Iterator">
+    <DisplayString>({_Key_it}, {_Mapped_it})</DisplayString>
+    <Expand>
+      <Item Name="[key]">_Key_it</Item>
+      <Item Name="[value]">_Mapped_it</Item>
+    </Expand>
+  </Type>
+
+  <Type Name="std::flat_set&lt;*&gt;">
+    <AlternativeType Name="std::flat_multiset&lt;*&gt;"/>
+    <DisplayString>{_Data}</DisplayString>
+    <Expand>
+      <Item Name="[comparator]" ExcludeView="simple">_Key_compare</Item>
+      <ExpandedItem>_Data</ExpandedItem>
+    </Expand>
+  </Type>
+
 </AutoVisualizer>

stl/inc/__msvc_all_public_headers.hpp

@@ -83,6 +83,8 @@
 #include <exception>
 #include <expected>
 #include <filesystem>
+#include <flat_map>
+#include <flat_set>
 #include <format>
 #include <forward_list>
 #include <fstream>

stl/inc/__msvc_string_view.hpp

@@ -2148,6 +2148,12 @@ inline namespace literals {
     } // namespace string_view_literals
 } // namespace literals
 #endif // _HAS_CXX17
+
+#if _HAS_CXX23
+template <class _Elem, class _Traits>
+constexpr bool _Equivalence_is_equality_impl<basic_string_view<_Elem, _Traits>> =
+    _Is_implementation_handled_char_traits<_Traits>;
+#endif // _HAS_CXX23
 _STD_END
 
 #pragma pop_macro("new")

stl/inc/algorithm

@@ -8564,14 +8564,13 @@ void inplace_merge(_BidIt _First, _BidIt _Mid, _BidIt _Last, _Pr _Pred) {
 
     ++_ULast;
 
-    using _Diff         = _Iter_diff_t<_BidIt>;
-    const _Diff _Count1 = _STD distance(_UFirst, _UMid);
+    const auto _Count1 = _STD distance(_UFirst, _UMid);
     if (_Count1 == 1) { // rotate only element remaining in left partition to the end, without allocating
         _STD _Rotate_one_left(_UFirst, _UMid, _ULast);
         return;
     }
 
-    const _Diff _Count2 = _STD distance(_UMid, _ULast);
+    const auto _Count2 = _STD distance(_UMid, _ULast);
     _Optimistic_temporary_buffer2<_Iter_value_t<_BidIt>> _Temp_buf{(_STD min) (_Count1, _Count2)};
     _STD _Buffered_inplace_merge_unchecked_impl(
         _UFirst, _UMid, _ULast, _Count1, _Count2, _Temp_buf._Data, _Temp_buf._Capacity, _STD _Pass_fn(_Pred));

stl/inc/deque

@@ -1848,6 +1848,14 @@ namespace pmr {
     using deque = _STD deque<_Ty, polymorphic_allocator<_Ty>>;
 } // namespace pmr
 #endif // _HAS_CXX17
+
+#if _HAS_CXX23
+template <class _Ty, class _Alloc>
+constexpr bool _Has_guaranteed_push_back<deque<_Ty, _Alloc>> = true;
+
+template <class _Ty, class _Alloc>
+constexpr bool _Has_guaranteed_append_range<deque<_Ty, _Alloc>> = true;
+#endif // _HAS_CXX23
 _STD_END
 
 #pragma pop_macro("new")