A benchmark for some elementary functions

benchmarks/benchmarks.vcxproj

@@ -18,6 +18,7 @@
     <ClCompile Include="apsides_benchmark.cpp" />
     <ClCompile Include="checkpointer_benchmark.cpp" />
     <ClCompile Include="discrete_trajectory_benchmark.cpp" />
+    <ClCompile Include="elementary_functions_benchmark.cpp" />
     <ClCompile Include="lagrange_equipotentials_benchmark.cpp" />
     <ClCompile Include="polynomial_in_monomial_basis_benchmark.cpp" />
     <ClCompile Include="polynomial_in_чебышёв_basis_benchmark.cpp" />

benchmarks/benchmarks.vcxproj.filters

@@ -86,6 +86,9 @@
     <ClCompile Include="polynomial_in_чебышёв_basis_benchmark.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
+    <ClCompile Include="elementary_functions_benchmark.cpp">
+      <Filter>Source Files</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="quantities.hpp">

benchmarks/elementary_functions_benchmark.cpp

@@ -0,0 +1,55 @@
+// .\Release\x64\benchmarks.exe --benchmark_repetitions=3 --benchmark_filter=BM_EvaluateElementaryFunction  // NOLINT(whitespace/line_length)
+
+#include <cmath>
+#include <random>
+
+#include "benchmark/benchmark.h"
+
+namespace principia {
+namespace functions {
+
+static constexpr std::int64_t number_of_iterations = 1000;
+
+enum class Metric { Latency, Throughput };
+
+template<Metric metric, double (__cdecl *fn)(double)>
+void BM_EvaluateElementaryFunction(benchmark::State& state) {
+  using Value = double;
+  using Argument = double;
+
+  std::mt19937_64 random(42);
+  std::uniform_real_distribution<> uniformly_at(-1.0, 1.0);
+  Argument argument = uniformly_at(random);
+
+  if constexpr (metric == Metric::Throughput) {
+    Value v[number_of_iterations];
+    while (state.KeepRunningBatch(number_of_iterations)) {
+      for (std::int64_t i = 0; i < number_of_iterations; ++i) {
+        v[i] = fn(argument);
+      }
+      benchmark::DoNotOptimize(v);
+    }
+  } else {
+    static_assert(metric == Metric::Latency);
+    Value v;
+    while (state.KeepRunningBatch(number_of_iterations)) {
+      for (std::int64_t i = 0; i < number_of_iterations; ++i) {
+        v = fn(argument);
+        argument = v;
+      }
+    }
+  }
+}
+
+BENCHMARK_TEMPLATE(BM_EvaluateElementaryFunction, Metric::Latency, std::sin)
+    ->Unit(benchmark::kNanosecond);
+BENCHMARK_TEMPLATE(BM_EvaluateElementaryFunction, Metric::Throughput, std::sin)
+    ->Unit(benchmark::kNanosecond);
+
+BENCHMARK_TEMPLATE(BM_EvaluateElementaryFunction, Metric::Latency, std::cos)
+    ->Unit(benchmark::kNanosecond);
+BENCHMARK_TEMPLATE(BM_EvaluateElementaryFunction, Metric::Throughput, std::cos)
+    ->Unit(benchmark::kNanosecond);
+
+}  // namespace functions
+}  // namespace principia