[libcxx-commits] [libcxx] [libcxx][algorithm] Optimize std::stable_sort via radix sort algorithm (PR #104683)

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In-Reply-To: <llvm.org/llvm/llvm-project/pull/104683 at github.com>


github-actions[bot] wrote:

<!--LLVM CODE FORMAT COMMENT: {clang-format}-->


:warning: C/C++ code formatter, clang-format found issues in your code. :warning:

<details>
<summary>
You can test this locally with the following command:
</summary>

``````````bash
git-clang-format --diff f3cf24fcc46ab1b9612d7dcb55ec5f18ea2dc62f a0c3857e0701b5ec89e45eaf29bbd546deed6aa8 --extensions cpp,h -- libcxx/include/__algorithm/radix_sort.h libcxx/include/__algorithm/stable_sort.h libcxx/include/__bit/bit_log2.h libcxx/test/std/algorithms/alg.sorting/alg.sort/stable.sort/stable_sort.pass.cpp
``````````

</details>

<details>
<summary>
View the diff from clang-format here.
</summary>

``````````diff
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.sort/stable.sort/stable_sort.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.sort/stable.sort/stable_sort.pass.cpp
index 3fcaeec90c..730f7080cf 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.sort/stable.sort/stable_sort.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.sort/stable.sort/stable_sort.pass.cpp
@@ -50,15 +50,13 @@ template <class RI>
 void
 test_sort_driver_driver(RI f, RI l, int start, RI real_last)
 {
-    typedef typename std::iterator_traits<RI>::value_type value_type;
+  typedef typename std::iterator_traits<RI>::value_type value_type;
 
-    for (RI i = l; i > f + start;)
-    {
-        *--i = static_cast<value_type>(start);
-        if (f == i)
-        {
-            test_sort_helper(f, real_last);
-        }
+  for (RI i = l; i > f + start;) {
+    *--i = static_cast<value_type>(start);
+    if (f == i) {
+      test_sort_helper(f, real_last);
+    }
     if (start > 0)
         test_sort_driver_driver(f, i, start-1, real_last);
     }
@@ -72,70 +70,60 @@ test_sort_driver(RI f, RI l, int start)
 }
 
 template <int sa, class V>
-void
-test_sort_()
-{
-    V ia[sa];
-    for (int i = 0; i < sa; ++i)
-    {
-        test_sort_driver(ia, ia+sa, i);
-    }
+void test_sort_() {
+  V ia[sa];
+  for (int i = 0; i < sa; ++i) {
+    test_sort_driver(ia, ia + sa, i);
+  }
 }
 
 template <int sa>
-void
-test_sort_()
-{
-    test_sort_<sa, int>();
-    test_sort_<sa, float>();
+void test_sort_() {
+  test_sort_<sa, int>();
+  test_sort_<sa, float>();
 }
 
 template <class V>
-void
-test_larger_sorts(int N, int M)
-{
-    assert(N != 0);
-    assert(M != 0);
-    // create array length N filled with M different numbers
-    V* array = new V[N];
-    int x = 0;
-    for (int i = 0; i < N; ++i)
-    {
-        array[i] = static_cast<V>(x);
-        if (++x == M)
-            x = 0;
-    }
-    // test saw tooth pattern
-    std::stable_sort(array, array+N);
-    assert(std::is_sorted(array, array+N));
-    // test random pattern
-    std::shuffle(array, array+N, randomness);
-    std::stable_sort(array, array+N);
-    assert(std::is_sorted(array, array+N));
-    // test sorted pattern
-    std::stable_sort(array, array+N);
-    assert(std::is_sorted(array, array+N));
-    // test reverse sorted pattern
-    std::reverse(array, array+N);
-    std::stable_sort(array, array+N);
-    assert(std::is_sorted(array, array+N));
-    // test swap ranges 2 pattern
-    std::swap_ranges(array, array+N/2, array+N/2);
-    std::stable_sort(array, array+N);
-    assert(std::is_sorted(array, array+N));
-    // test reverse swap ranges 2 pattern
-    std::reverse(array, array+N);
-    std::swap_ranges(array, array+N/2, array+N/2);
-    std::stable_sort(array, array+N);
-    assert(std::is_sorted(array, array+N));
-    delete [] array;
+void test_larger_sorts(int N, int M) {
+  assert(N != 0);
+  assert(M != 0);
+  // create array length N filled with M different numbers
+  V* array = new V[N];
+  int x    = 0;
+  for (int i = 0; i < N; ++i) {
+    array[i] = static_cast<V>(x);
+    if (++x == M)
+      x = 0;
+  }
+  // test saw tooth pattern
+  std::stable_sort(array, array + N);
+  assert(std::is_sorted(array, array + N));
+  // test random pattern
+  std::shuffle(array, array + N, randomness);
+  std::stable_sort(array, array + N);
+  assert(std::is_sorted(array, array + N));
+  // test sorted pattern
+  std::stable_sort(array, array + N);
+  assert(std::is_sorted(array, array + N));
+  // test reverse sorted pattern
+  std::reverse(array, array + N);
+  std::stable_sort(array, array + N);
+  assert(std::is_sorted(array, array + N));
+  // test swap ranges 2 pattern
+  std::swap_ranges(array, array + N / 2, array + N / 2);
+  std::stable_sort(array, array + N);
+  assert(std::is_sorted(array, array + N));
+  // test reverse swap ranges 2 pattern
+  std::reverse(array, array + N);
+  std::swap_ranges(array, array + N / 2, array + N / 2);
+  std::stable_sort(array, array + N);
+  assert(std::is_sorted(array, array + N));
+  delete[] array;
 }
 
-void
-test_larger_sorts(int N, int M)
-{
-    test_larger_sorts<int>(N, M);
-    test_larger_sorts<float>(N, M);
+void test_larger_sorts(int N, int M) {
+  test_larger_sorts<int>(N, M);
+  test_larger_sorts<float>(N, M);
 }
 
 void

``````````

</details>


https://github.com/llvm/llvm-project/pull/104683