Add co_sm utility with coroutine policies, tests, and benchmark

benchmark/simple/CMakeLists.txt

@@ -13,4 +13,5 @@ add_example(simple_sc benchmark_simple_sc sc.cpp)
 
 if (NOT IS_MSVC_2015)
   add_example(simple_sml benchmark_simple_sml sml.cpp)
+  add_example(simple_co_sm benchmark_simple_co_sm co_sm.cpp)
 endif()

benchmark/simple/co_sm.cpp

@@ -0,0 +1,101 @@
+//
+// Copyright (c) 2016-2026 Kris Jusiak (kris at jusiak dot net)
+//
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+//
+#include <boost/sml.hpp>
+#include <boost/sml/utility/co_sm.hpp>
+
+#include "benchmark.hpp"
+
+namespace sml = boost::sml;
+
+struct play {};
+struct end_pause {};
+struct stop {};
+struct pause {};
+struct open_close {};
+struct cd_detected {};
+
+auto start_playback = [] {};
+auto resume_playback = [] {};
+auto close_drawer = [] {};
+auto open_drawer = [] {};
+auto stop_and_open = [] {};
+auto stopped_again = [] {};
+auto store_cd_info = [] {};
+auto pause_playback = [] {};
+auto stop_playback = [] {};
+
+struct player {
+  auto operator()() const noexcept {
+    using namespace sml;
+    auto Empty = state<class Empty>;
+    auto Open = state<class Open>;
+    auto Stopped = state<class Stopped>;
+    auto Playing = state<class Playing>;
+    auto Pause = state<class Pause>;
+
+    // clang-format off
+    return make_transition_table(
+        Playing <= Stopped + event<play> / start_playback,
+        Playing <= Pause + event<end_pause> / resume_playback,
+        Empty <= Open + event<open_close> / close_drawer,
+        Open <= *Empty + event<open_close> / open_drawer,
+        Open <= Pause + event<open_close> / stop_and_open,
+        Open <= Stopped + event<open_close> / open_drawer,
+        Open <= Playing + event<open_close> / stop_and_open,
+        Pause <= Playing + event<pause> / pause_playback,
+        Stopped <= Playing + event<stop> / stop_playback,
+        Stopped <= Pause + event<stop> / stop_playback,
+        Stopped <= Empty + event<cd_detected> / store_cd_info,
+        Stopped <= Stopped + event<stop> / stopped_again
+    );
+    // clang-format on
+  }
+};
+
+int main() {
+#if BOOST_SML_UTILITY_CO_SM_ENABLED
+  using co_sm_t =
+      sml::utility::co_sm<player, sml::utility::policy::coroutine_scheduler<sml::utility::policy::inline_scheduler>>;
+  co_sm_t sm{};
+
+  benchmark_execution_speed([&] {
+    for (auto i = 0; i < 1'000'000; ++i) {
+      sm.process_event_async(open_close{}).result();
+      sm.process_event_async(open_close{}).result();
+      sm.process_event_async(cd_detected{}).result();
+      sm.process_event_async(play{}).result();
+      sm.process_event_async(pause{}).result();
+      sm.process_event_async(end_pause{}).result();
+      sm.process_event_async(pause{}).result();
+      sm.process_event_async(stop{}).result();
+      sm.process_event_async(stop{}).result();
+      sm.process_event_async(open_close{}).result();
+      sm.process_event_async(open_close{}).result();
+    }
+  });
+  benchmark_memory_usage(sm);
+#else
+  sml::sm<player> sm{};
+  benchmark_execution_speed([&] {
+    for (auto i = 0; i < 1'000'000; ++i) {
+      sm.process_event(open_close{});
+      sm.process_event(open_close{});
+      sm.process_event(cd_detected{});
+      sm.process_event(play{});
+      sm.process_event(pause{});
+      sm.process_event(end_pause{});
+      sm.process_event(pause{});
+      sm.process_event(stop{});
+      sm.process_event(stop{});
+      sm.process_event(open_close{});
+      sm.process_event(open_close{});
+    }
+  });
+  benchmark_memory_usage(sm);
+#endif
+}