[libcxx-commits] [libcxx] [libc++] experiment with atomic_sync (PR #84471)

[via libcxx-commits]

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 7c1c07c92099d3e36e8f362706a5824ab04bdf38 983fec1f96f8f2c3ecfd070b8124c0b5f94618dc -- libcxx/benchmarks/atomic_wait.bench.cpp
``````````

</details>

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

``````````diff
diff --git a/libcxx/benchmarks/atomic_wait.bench.cpp b/libcxx/benchmarks/atomic_wait.bench.cpp
index afe8c447a7..20aae0f4eb 100644
--- a/libcxx/benchmarks/atomic_wait.bench.cpp
+++ b/libcxx/benchmarks/atomic_wait.bench.cpp
@@ -51,13 +51,11 @@ struct HighPrioTask {
   }
 };
 
-
 template <std::size_t N>
 struct NumHighPrioTasks {
   static constexpr auto value = N;
 };
 
-
 struct KeepNotifying {
   template <class Atomic>
   static void notify(Atomic& a, std::stop_token st) {
@@ -100,18 +98,35 @@ void BM_1_atomic_1_waiter_1_notifier(benchmark::State& state) {
   }
 }
 
-BENCHMARK(BM_1_atomic_1_waiter_1_notifier<KeepNotifying, NumHighPrioTasks<0>>)->RangeMultiplier(2)->Range(1 << 10, 1 << 24);
-BENCHMARK(BM_1_atomic_1_waiter_1_notifier<NotifyEveryNus<50>, NumHighPrioTasks<0>>)->RangeMultiplier(2)->Range(1 << 10, 1 << 16);
-BENCHMARK(BM_1_atomic_1_waiter_1_notifier<NotifyEveryNus<100>, NumHighPrioTasks<0>>)->RangeMultiplier(2)->Range(1 << 10, 1 << 16);
-
-BENCHMARK(BM_1_atomic_1_waiter_1_notifier<KeepNotifying, NumHighPrioTasks<4>>)->RangeMultiplier(2)->Range(1 << 10, 1 << 24);
-BENCHMARK(BM_1_atomic_1_waiter_1_notifier<NotifyEveryNus<50>, NumHighPrioTasks<4>>)->RangeMultiplier(2)->Range(1 << 10, 1 << 16);
-BENCHMARK(BM_1_atomic_1_waiter_1_notifier<NotifyEveryNus<100>, NumHighPrioTasks<4>>)->RangeMultiplier(2)->Range(1 << 10, 1 << 16);
+BENCHMARK(BM_1_atomic_1_waiter_1_notifier<KeepNotifying, NumHighPrioTasks<0>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 10, 1 << 24);
+BENCHMARK(BM_1_atomic_1_waiter_1_notifier<NotifyEveryNus<50>, NumHighPrioTasks<0>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 10, 1 << 16);
+BENCHMARK(BM_1_atomic_1_waiter_1_notifier<NotifyEveryNus<100>, NumHighPrioTasks<0>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 10, 1 << 16);
 
-BENCHMARK(BM_1_atomic_1_waiter_1_notifier<KeepNotifying, NumHighPrioTasks<7>>)->RangeMultiplier(2)->Range(1 << 4, 1 << 8);
-BENCHMARK(BM_1_atomic_1_waiter_1_notifier<NotifyEveryNus<50>, NumHighPrioTasks<7>>)->RangeMultiplier(2)->Range(1 << 4, 1 << 8);
-BENCHMARK(BM_1_atomic_1_waiter_1_notifier<NotifyEveryNus<100>, NumHighPrioTasks<7>>)->RangeMultiplier(2)->Range(1 << 4, 1 << 8);
+BENCHMARK(BM_1_atomic_1_waiter_1_notifier<KeepNotifying, NumHighPrioTasks<4>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 10, 1 << 24);
+BENCHMARK(BM_1_atomic_1_waiter_1_notifier<NotifyEveryNus<50>, NumHighPrioTasks<4>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 10, 1 << 16);
+BENCHMARK(BM_1_atomic_1_waiter_1_notifier<NotifyEveryNus<100>, NumHighPrioTasks<4>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 10, 1 << 16);
 
+BENCHMARK(BM_1_atomic_1_waiter_1_notifier<KeepNotifying, NumHighPrioTasks<7>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 4, 1 << 8);
+BENCHMARK(BM_1_atomic_1_waiter_1_notifier<NotifyEveryNus<50>, NumHighPrioTasks<7>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 4, 1 << 8);
+BENCHMARK(BM_1_atomic_1_waiter_1_notifier<NotifyEveryNus<100>, NumHighPrioTasks<7>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 4, 1 << 8);
 
 template <std::size_t N>
 struct NumWaitingThreads {
@@ -198,7 +213,6 @@ BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<100>, NumWaitingThr
     ->RangeMultiplier(2)
     ->Range(1 << 8, 1 << 14);
 
-
 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<KeepNotifying, NumWaitingThreads<3>, NumHighPrioTasks<4>>)
     ->RangeMultiplier(2)
     ->Range(1 << 10, 1 << 18);
@@ -259,7 +273,6 @@ BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<100>, NumWaitingThr
     ->RangeMultiplier(2)
     ->Range(1 << 4, 1 << 8);
 
-
 template <std::size_t N>
 struct NumberOfAtomics {
   static constexpr auto value = N;
@@ -326,83 +339,82 @@ void BM_N_atomics_N_waiter_N_notifier(benchmark::State& state) {
   }
 }
 
- BENCHMARK(BM_N_atomics_N_waiter_N_notifier<KeepNotifying, NumberOfAtomics<2>, NumHighPrioTasks<0>>)
-     ->RangeMultiplier(2)
-     ->Range(1 << 10, 1 << 20);
- BENCHMARK(BM_N_atomics_N_waiter_N_notifier<KeepNotifying, NumberOfAtomics<3>, NumHighPrioTasks<0>>)
-     ->RangeMultiplier(2)
-     ->Range(1 << 10, 1 << 20);
- BENCHMARK(BM_N_atomics_N_waiter_N_notifier<KeepNotifying, NumberOfAtomics<5>, NumHighPrioTasks<0>>)
-     ->RangeMultiplier(2)
-     ->Range(1 << 10, 1 << 20);
- BENCHMARK(BM_N_atomics_N_waiter_N_notifier<KeepNotifying, NumberOfAtomics<7>, NumHighPrioTasks<0>>)
-     ->RangeMultiplier(2)
-     ->Range(1 << 10, 1 << 20);
-
- BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<50>, NumberOfAtomics<2>, NumHighPrioTasks<0>>)
-     ->RangeMultiplier(2)
-     ->Range(1 << 10, 1 << 16);
- BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<50>, NumberOfAtomics<3>, NumHighPrioTasks<0>>)
-     ->RangeMultiplier(2)
-     ->Range(1 << 10, 1 << 16);
- BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<50>, NumberOfAtomics<5>, NumHighPrioTasks<0>>)
-     ->RangeMultiplier(2)
-     ->Range(1 << 10, 1 << 16);
- BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<50>, NumberOfAtomics<7>, NumHighPrioTasks<0>>)
-     ->RangeMultiplier(2)
-     ->Range(1 << 10, 1 << 16);
-
- BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<100>, NumberOfAtomics<2>, NumHighPrioTasks<0>>)
-     ->RangeMultiplier(2)
-     ->Range(1 << 8, 1 << 14);
- BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<100>, NumberOfAtomics<3>, NumHighPrioTasks<0>>)
-     ->RangeMultiplier(2)
-     ->Range(1 << 8, 1 << 14);
- BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<100>, NumberOfAtomics<5>, NumHighPrioTasks<0>>)
-     ->RangeMultiplier(2)
-     ->Range(1 << 8, 1 << 14);
- BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<100>, NumberOfAtomics<7>, NumHighPrioTasks<0>>)
-     ->RangeMultiplier(2)
-     ->Range(1 << 8, 1 << 14);
-
- BENCHMARK(BM_N_atomics_N_waiter_N_notifier<KeepNotifying, NumberOfAtomics<2>, NumHighPrioTasks<4>>)
-     ->RangeMultiplier(2)
-     ->Range(1 << 10, 1 << 20);
- BENCHMARK(BM_N_atomics_N_waiter_N_notifier<KeepNotifying, NumberOfAtomics<3>, NumHighPrioTasks<4>>)
-     ->RangeMultiplier(2)
-     ->Range(1 << 10, 1 << 20);
- BENCHMARK(BM_N_atomics_N_waiter_N_notifier<KeepNotifying, NumberOfAtomics<5>, NumHighPrioTasks<4>>)
-     ->RangeMultiplier(2)
-     ->Range(1 << 10, 1 << 20);
- BENCHMARK(BM_N_atomics_N_waiter_N_notifier<KeepNotifying, NumberOfAtomics<7>, NumHighPrioTasks<4>>)
-     ->RangeMultiplier(2)
-     ->Range(1 << 10, 1 << 20);
-
- BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<50>, NumberOfAtomics<2>, NumHighPrioTasks<4>>)
-     ->RangeMultiplier(2)
-     ->Range(1 << 10, 1 << 16);
- BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<50>, NumberOfAtomics<3>, NumHighPrioTasks<4>>)
-     ->RangeMultiplier(2)
-     ->Range(1 << 10, 1 << 16);
- BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<50>, NumberOfAtomics<5>, NumHighPrioTasks<4>>)
-     ->RangeMultiplier(2)
-     ->Range(1 << 10, 1 << 16);
- BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<50>, NumberOfAtomics<7>, NumHighPrioTasks<4>>)
-     ->RangeMultiplier(2)
-     ->Range(1 << 10, 1 << 16);
-
-
- BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<100>, NumberOfAtomics<2>, NumHighPrioTasks<4>>)
-     ->RangeMultiplier(2)
-     ->Range(1 << 8, 1 << 14);
- BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<100>, NumberOfAtomics<3>, NumHighPrioTasks<4>>)
-     ->RangeMultiplier(2)
-     ->Range(1 << 8, 1 << 14);
- BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<100>, NumberOfAtomics<5>, NumHighPrioTasks<4>>)
-     ->RangeMultiplier(2)
-     ->Range(1 << 6, 1 << 10);
- BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<100>, NumberOfAtomics<7>, NumHighPrioTasks<4>>)
-     ->RangeMultiplier(2)
-     ->Range(1 << 4, 1 << 8);
+BENCHMARK(BM_N_atomics_N_waiter_N_notifier<KeepNotifying, NumberOfAtomics<2>, NumHighPrioTasks<0>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 10, 1 << 20);
+BENCHMARK(BM_N_atomics_N_waiter_N_notifier<KeepNotifying, NumberOfAtomics<3>, NumHighPrioTasks<0>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 10, 1 << 20);
+BENCHMARK(BM_N_atomics_N_waiter_N_notifier<KeepNotifying, NumberOfAtomics<5>, NumHighPrioTasks<0>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 10, 1 << 20);
+BENCHMARK(BM_N_atomics_N_waiter_N_notifier<KeepNotifying, NumberOfAtomics<7>, NumHighPrioTasks<0>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 10, 1 << 20);
+
+BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<50>, NumberOfAtomics<2>, NumHighPrioTasks<0>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 10, 1 << 16);
+BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<50>, NumberOfAtomics<3>, NumHighPrioTasks<0>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 10, 1 << 16);
+BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<50>, NumberOfAtomics<5>, NumHighPrioTasks<0>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 10, 1 << 16);
+BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<50>, NumberOfAtomics<7>, NumHighPrioTasks<0>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 10, 1 << 16);
+
+BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<100>, NumberOfAtomics<2>, NumHighPrioTasks<0>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 8, 1 << 14);
+BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<100>, NumberOfAtomics<3>, NumHighPrioTasks<0>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 8, 1 << 14);
+BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<100>, NumberOfAtomics<5>, NumHighPrioTasks<0>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 8, 1 << 14);
+BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<100>, NumberOfAtomics<7>, NumHighPrioTasks<0>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 8, 1 << 14);
+
+BENCHMARK(BM_N_atomics_N_waiter_N_notifier<KeepNotifying, NumberOfAtomics<2>, NumHighPrioTasks<4>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 10, 1 << 20);
+BENCHMARK(BM_N_atomics_N_waiter_N_notifier<KeepNotifying, NumberOfAtomics<3>, NumHighPrioTasks<4>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 10, 1 << 20);
+BENCHMARK(BM_N_atomics_N_waiter_N_notifier<KeepNotifying, NumberOfAtomics<5>, NumHighPrioTasks<4>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 10, 1 << 20);
+BENCHMARK(BM_N_atomics_N_waiter_N_notifier<KeepNotifying, NumberOfAtomics<7>, NumHighPrioTasks<4>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 10, 1 << 20);
+
+BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<50>, NumberOfAtomics<2>, NumHighPrioTasks<4>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 10, 1 << 16);
+BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<50>, NumberOfAtomics<3>, NumHighPrioTasks<4>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 10, 1 << 16);
+BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<50>, NumberOfAtomics<5>, NumHighPrioTasks<4>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 10, 1 << 16);
+BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<50>, NumberOfAtomics<7>, NumHighPrioTasks<4>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 10, 1 << 16);
+
+BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<100>, NumberOfAtomics<2>, NumHighPrioTasks<4>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 8, 1 << 14);
+BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<100>, NumberOfAtomics<3>, NumHighPrioTasks<4>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 8, 1 << 14);
+BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<100>, NumberOfAtomics<5>, NumHighPrioTasks<4>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 6, 1 << 10);
+BENCHMARK(BM_N_atomics_N_waiter_N_notifier<NotifyEveryNus<100>, NumberOfAtomics<7>, NumHighPrioTasks<4>>)
+    ->RangeMultiplier(2)
+    ->Range(1 << 4, 1 << 8);
 
 BENCHMARK_MAIN();

``````````

</details>


https://github.com/llvm/llvm-project/pull/84471