Add benchmarks for settings access

apps/benchmarks/CMakeLists.txt

@@ -4,3 +4,4 @@ endif()
 
 add_subdirectory(detournavigator)
 add_subdirectory(esm)
+add_subdirectory(settings)

apps/benchmarks/settings/CMakeLists.txt

@@ -0,0 +1,15 @@
+openmw_add_executable(openmw_settings_access_benchmark access.cpp)
+target_link_libraries(openmw_settings_access_benchmark benchmark::benchmark components)
+
+if (UNIX AND NOT APPLE)
+    target_link_libraries(openmw_settings_access_benchmark ${CMAKE_THREAD_LIBS_INIT})
+endif()
+
+if (CMAKE_VERSION VERSION_GREATER_EQUAL 3.16 AND MSVC)
+    target_precompile_headers(openmw_settings_access_benchmark PRIVATE <algorithm>)
+endif()
+
+if (BUILD_WITH_CODE_COVERAGE)
+    target_compile_options(openmw_settings_access_benchmark PRIVATE --coverage)
+    target_link_libraries(openmw_settings_access_benchmark gcov)
+endif()

apps/benchmarks/settings/access.cpp

@@ -0,0 +1,86 @@
+#include <benchmark/benchmark.h>
+
+#include <components/files/configurationmanager.hpp>
+#include <components/settings/settings.hpp>
+#include <components/settings/values.hpp>
+
+#include <boost/program_options.hpp>
+
+#include <algorithm>
+#include <iostream>
+
+namespace
+{
+    namespace bpo = boost::program_options;
+
+    bpo::options_description makeOptionsDescription()
+    {
+        bpo::options_description result;
+        auto addOption = result.add_options();
+        addOption("help", "print help message");
+        Files::ConfigurationManager::addCommonOptions(result);
+        return result;
+    }
+
+    void settingsManager(benchmark::State& state)
+    {
+        for (auto _ : state)
+        {
+            benchmark::DoNotOptimize(Settings::Manager::getFloat("sky blending start", "Fog"));
+        }
+    }
+
+    void localStatic(benchmark::State& state)
+    {
+        for (auto _ : state)
+        {
+            static const float v = Settings::Manager::getFloat("sky blending start", "Fog");
+            benchmark::DoNotOptimize(v);
+        }
+    }
+
+    void settingsStorage(benchmark::State& state)
+    {
+        for (auto _ : state)
+        {
+            benchmark::DoNotOptimize(Settings::fog().mSkyBlendingStart.get());
+        }
+    }
+}
+
+BENCHMARK(settingsManager);
+BENCHMARK(localStatic);
+BENCHMARK(settingsStorage);
+
+int main(int argc, char* argv[])
+{
+    bpo::options_description desc = makeOptionsDescription();
+
+    bpo::parsed_options options = bpo::command_line_parser(argc, argv).options(desc).allow_unregistered().run();
+    bpo::variables_map variables;
+
+    bpo::store(options, variables);
+    bpo::notify(variables);
+
+    if (variables.find("help") != variables.end())
+    {
+        std::cout << desc << std::endl;
+        benchmark::Initialize(&argc, argv);
+        benchmark::Shutdown();
+        return 1;
+    }
+
+    Files::ConfigurationManager config;
+
+    bpo::variables_map composingVariables = Files::separateComposingVariables(variables, desc);
+    config.readConfiguration(variables, desc);
+    Files::mergeComposingVariables(variables, composingVariables, desc);
+
+    Settings::Manager::load(config);
+
+    benchmark::Initialize(&argc, argv);
+    benchmark::RunSpecifiedBenchmarks();
+    benchmark::Shutdown();
+
+    return 0;
+}