[libcxx-commits] [libcxx] 162397f - [libc++] Replace stable_sort with sort in flat_map (#121431)
via libcxx-commits
libcxx-commits at lists.llvm.org
Mon Jan 13 06:09:34 PST 2025
Author: Hui
Date: 2025-01-13T09:09:29-05:00
New Revision: 162397f98d04415eebe115cdcb01558932e5c802
URL: https://github.com/llvm/llvm-project/commit/162397f98d04415eebe115cdcb01558932e5c802
DIFF: https://github.com/llvm/llvm-project/commit/162397f98d04415eebe115cdcb01558932e5c802.diff
LOG: [libc++] Replace stable_sort with sort in flat_map (#121431)
Fixes #120788
Added:
Modified:
libcxx/include/__flat_map/flat_map.h
libcxx/include/module.modulemap
Removed:
libcxx/test/libcxx/containers/containers.adaptors/flat.map/container_stability.pass.cpp
libcxx/test/std/containers/container.adaptors/flat.map/flat.map.cons/iter_iter_stability.pass.cpp
libcxx/test/std/containers/container.adaptors/flat.map/flat.map.modifiers/insert_range_stability.pass.cpp
################################################################################
diff --git a/libcxx/include/__flat_map/flat_map.h b/libcxx/include/__flat_map/flat_map.h
index 9fe84250b12043..ab53b7a285ca46 100644
--- a/libcxx/include/__flat_map/flat_map.h
+++ b/libcxx/include/__flat_map/flat_map.h
@@ -17,7 +17,7 @@
#include <__algorithm/ranges_inplace_merge.h>
#include <__algorithm/ranges_lower_bound.h>
#include <__algorithm/ranges_partition_point.h>
-#include <__algorithm/ranges_stable_sort.h>
+#include <__algorithm/ranges_sort.h>
#include <__algorithm/ranges_unique.h>
#include <__algorithm/ranges_upper_bound.h>
#include <__algorithm/remove_if.h>
@@ -853,9 +853,7 @@ class flat_map {
// is no invariant state to preserve
_LIBCPP_HIDE_FROM_ABI void __sort_and_unique() {
auto __zv = ranges::views::zip(__containers_.keys, __containers_.values);
- // To be consistent with std::map's behaviour, we use stable_sort instead of sort.
- // As a result, if there are duplicated keys, the first value in the original order will be taken.
- ranges::stable_sort(__zv, __compare_, [](const auto& __p) -> decltype(auto) { return std::get<0>(__p); });
+ ranges::sort(__zv, __compare_, [](const auto& __p) -> decltype(auto) { return std::get<0>(__p); });
auto __dup_start = ranges::unique(__zv, __key_equiv(__compare_)).begin();
auto __dist = ranges::distance(__zv.begin(), __dup_start);
__containers_.keys.erase(__containers_.keys.begin() + __dist, __containers_.keys.end());
@@ -886,7 +884,7 @@ class flat_map {
return __compare_(std::get<0>(__p1), std::get<0>(__p2));
};
if constexpr (!_WasSorted) {
- ranges::stable_sort(__zv.begin() + __append_start_offset, __end, __compare_key);
+ ranges::sort(__zv.begin() + __append_start_offset, __end, __compare_key);
} else {
_LIBCPP_ASSERT_SEMANTIC_REQUIREMENT(
__is_sorted_and_unique(__containers_.keys | ranges::views::drop(__append_start_offset)),
diff --git a/libcxx/include/module.modulemap b/libcxx/include/module.modulemap
index 07ab5649ae45cb..6800f8b5626504 100644
--- a/libcxx/include/module.modulemap
+++ b/libcxx/include/module.modulemap
@@ -760,6 +760,8 @@ module std [system] {
module ranges_sort {
header "__algorithm/ranges_sort.h"
export std.functional.ranges_operations
+ export std.algorithm.sort
+ export std.algorithm.make_projected
}
module ranges_stable_partition {
header "__algorithm/ranges_stable_partition.h"
diff --git a/libcxx/test/libcxx/containers/containers.adaptors/flat.map/container_stability.pass.cpp b/libcxx/test/libcxx/containers/containers.adaptors/flat.map/container_stability.pass.cpp
deleted file mode 100644
index 0d90c3250061ff..00000000000000
--- a/libcxx/test/libcxx/containers/containers.adaptors/flat.map/container_stability.pass.cpp
+++ /dev/null
@@ -1,68 +0,0 @@
-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
-
-// <flat_map>
-
-// flat_map(key_container_type key_cont, mapped_container_type mapped_cont);
-//
-// libc++ uses stable_sort to ensure that flat_map's behavior matches map's,
-// in terms of which duplicate items are kept.
-// This tests a conforming extension.
-
-#include <algorithm>
-#include <cassert>
-#include <cstdint>
-#include <flat_map>
-#include <random>
-#include <map>
-#include <vector>
-
-#include "test_macros.h"
-
-struct Mod256 {
- bool operator()(int x, int y) const { return (x % 256) < (y % 256); }
-};
-
-int main(int, char**) {
- std::mt19937 randomness;
- std::vector<uint16_t> values;
- std::vector<std::pair<uint16_t, uint16_t>> pairs;
- for (int i = 0; i < 200; ++i) {
- uint16_t r = randomness();
- values.push_back(r);
- pairs.emplace_back(r, r);
- }
-
- {
- std::map<uint16_t, uint16_t, Mod256> m(pairs.begin(), pairs.end());
- std::flat_map<uint16_t, uint16_t, Mod256> fm(values, values);
- assert(fm.size() == m.size());
- LIBCPP_ASSERT(std::ranges::equal(fm, m));
- }
- {
- std::map<uint16_t, uint16_t, Mod256> m(pairs.begin(), pairs.end());
- std::flat_map<uint16_t, uint16_t, Mod256> fm(values, values, Mod256());
- assert(fm.size() == m.size());
- LIBCPP_ASSERT(std::ranges::equal(fm, m));
- }
- {
- std::map<uint16_t, uint16_t, Mod256> m(pairs.begin(), pairs.end());
- std::flat_map<uint16_t, uint16_t, Mod256> fm(values, values, std::allocator<int>());
- assert(fm.size() == m.size());
- LIBCPP_ASSERT(std::ranges::equal(fm, m));
- }
- {
- std::map<uint16_t, uint16_t, Mod256> m(pairs.begin(), pairs.end());
- std::flat_map<uint16_t, uint16_t, Mod256> fm(values, values, Mod256(), std::allocator<int>());
- assert(fm.size() == m.size());
- LIBCPP_ASSERT(std::ranges::equal(fm, m));
- }
- return 0;
-}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.cons/iter_iter_stability.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.cons/iter_iter_stability.pass.cpp
deleted file mode 100644
index 14189840ce6605..00000000000000
--- a/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.cons/iter_iter_stability.pass.cpp
+++ /dev/null
@@ -1,66 +0,0 @@
-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
-
-// <flat_map>
-
-// template<class InputIterator>
-// flat_map(InputIterator first, InputIterator last, const key_compare& comp = key_compare())
-//
-// libc++ uses stable_sort to ensure that flat_map's behavior matches map's,
-// in terms of which duplicate items are kept.
-// This tests a conforming extension.
-
-#include <algorithm>
-#include <cassert>
-#include <cstdint>
-#include <flat_map>
-#include <random>
-#include <map>
-#include <vector>
-
-#include "test_macros.h"
-
-struct Mod256 {
- bool operator()(int x, int y) const { return (x % 256) < (y % 256); }
-};
-
-int main(int, char**) {
- std::mt19937 randomness;
- std::pair<uint16_t, uint16_t> pairs[200];
- for (auto& pair : pairs) {
- pair = {uint16_t(randomness()), uint16_t(randomness())};
- }
-
- {
- std::map<uint16_t, uint16_t, Mod256> m(pairs, pairs + 200);
- std::flat_map<uint16_t, uint16_t, Mod256> fm(pairs, pairs + 200);
- assert(fm.size() == m.size());
- LIBCPP_ASSERT(std::ranges::equal(fm, m));
- }
- {
- std::map<uint16_t, uint16_t, Mod256> m(pairs, pairs + 200, std::allocator<int>());
- std::flat_map<uint16_t, uint16_t, Mod256> fm(pairs, pairs + 200, std::allocator<int>());
- assert(fm.size() == m.size());
- LIBCPP_ASSERT(std::ranges::equal(fm, m));
- }
- {
- std::map<uint16_t, uint16_t, Mod256> m(pairs, pairs + 200, Mod256());
- std::flat_map<uint16_t, uint16_t, Mod256> fm(pairs, pairs + 200, Mod256());
- assert(fm.size() == m.size());
- LIBCPP_ASSERT(std::ranges::equal(fm, m));
- }
- {
- std::map<uint16_t, uint16_t, Mod256> m(pairs, pairs + 200, Mod256(), std::allocator<int>());
- std::flat_map<uint16_t, uint16_t, Mod256> fm(pairs, pairs + 200, Mod256(), std::allocator<int>());
- assert(fm.size() == m.size());
- LIBCPP_ASSERT(std::ranges::equal(fm, m));
- }
- return 0;
-}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.modifiers/insert_range_stability.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.modifiers/insert_range_stability.pass.cpp
deleted file mode 100644
index fabcb1d216a78a..00000000000000
--- a/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.modifiers/insert_range_stability.pass.cpp
+++ /dev/null
@@ -1,63 +0,0 @@
-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
-
-// <flat_map>
-
-// template<container-compatible-range<value_type> R>
-// void insert_range(R&& rg);
-//
-// libc++ uses stable_sort to ensure that flat_map's behavior matches map's,
-// in terms of which duplicate items are kept.
-// This tests a conforming extension.
-
-#include <algorithm>
-#include <cassert>
-#include <cstdint>
-#include <flat_map>
-#include <random>
-#include <ranges>
-#include <map>
-#include <vector>
-#include <utility>
-
-#include "test_macros.h"
-
-struct Mod256 {
- bool operator()(int x, int y) const { return (x % 256) < (y % 256); }
-};
-
-int main(int, char**) {
- {
- std::mt19937 randomness;
- std::pair<uint16_t, uint16_t> pairs[400];
- for (int i = 0; i < 400; ++i) {
- uint16_t r = randomness();
- pairs[i] = {r, r};
- }
-
- std::map<uint16_t, uint16_t, Mod256> m(pairs, pairs + 200);
- std::flat_map<uint16_t, uint16_t, Mod256> fm(std::sorted_unique, m.begin(), m.end());
- assert(std::ranges::equal(fm, m));
-
- fm.insert_range(std::views::counted(pairs + 200, 200));
- m.insert(pairs + 200, pairs + 400);
- assert(fm.size() == m.size());
- LIBCPP_ASSERT(std::ranges::equal(fm, m));
- }
-
- {
- std::vector<std::pair<int, int>> v{{1, 2}, {1, 3}};
- std::flat_map<int, int> m;
- m.insert_range(v);
- assert(m.size() == 1);
- LIBCPP_ASSERT(m[1] == 2);
- }
- return 0;
-}
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