From 32870f29bff4c46260607a17442894abe27ed88d Mon Sep 17 00:00:00 2001
From: pleroy <pascal.h.leroy@gmail.com>
Date: Wed, 17 Apr 2024 19:36:30 +0200
Subject: [PATCH 1/4] A benchmark for the trigonometric functions.

---
 benchmarks/benchmarks.vcxproj         |  1 +
 benchmarks/benchmarks.vcxproj.filters |  3 ++
 benchmarks/trigonometry_benchmark.cpp | 55 +++++++++++++++++++++++++++
 3 files changed, 59 insertions(+)
 create mode 100644 benchmarks/trigonometry_benchmark.cpp

diff --git a/benchmarks/benchmarks.vcxproj b/benchmarks/benchmarks.vcxproj
index 5906f20a3d..450a8d8398 100644
--- a/benchmarks/benchmarks.vcxproj
+++ b/benchmarks/benchmarks.vcxproj
@@ -38,6 +38,7 @@
     <ClCompile Include="quantities_benchmark.cpp" />
     <ClCompile Include="symplectic_runge_kutta_nyström_integrator_benchmark.cpp" />
     <ClCompile Include="thread_pool_benchmark.cpp" />
+    <ClCompile Include="trigonometry_benchmark.cpp" />
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="quantities.hpp" />
diff --git a/benchmarks/benchmarks.vcxproj.filters b/benchmarks/benchmarks.vcxproj.filters
index 8241497894..e46445ea61 100644
--- a/benchmarks/benchmarks.vcxproj.filters
+++ b/benchmarks/benchmarks.vcxproj.filters
@@ -86,6 +86,9 @@
     <ClCompile Include="polynomial_in_чебышёв_basis_benchmark.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
+    <ClCompile Include="trigonometry_benchmark.cpp">
+      <Filter>Source Files</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="quantities.hpp">
diff --git a/benchmarks/trigonometry_benchmark.cpp b/benchmarks/trigonometry_benchmark.cpp
new file mode 100644
index 0000000000..10d839c58c
--- /dev/null
+++ b/benchmarks/trigonometry_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

From 24178f92e59b486e9aac8fa5d32b2e4916859255 Mon Sep 17 00:00:00 2001
From: pleroy <pascal.h.leroy@gmail.com>
Date: Wed, 17 Apr 2024 19:42:09 +0200
Subject: [PATCH 2/4] Rename and a bigger range.

---
 benchmarks/benchmarks.vcxproj                                   | 2 +-
 ...nometry_benchmark.cpp => elementary_functions_benchmark.cpp} | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)
 rename benchmarks/{trigonometry_benchmark.cpp => elementary_functions_benchmark.cpp} (96%)

diff --git a/benchmarks/benchmarks.vcxproj b/benchmarks/benchmarks.vcxproj
index 450a8d8398..f3b065bf92 100644
--- a/benchmarks/benchmarks.vcxproj
+++ b/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" />
@@ -38,7 +39,6 @@
     <ClCompile Include="quantities_benchmark.cpp" />
     <ClCompile Include="symplectic_runge_kutta_nyström_integrator_benchmark.cpp" />
     <ClCompile Include="thread_pool_benchmark.cpp" />
-    <ClCompile Include="trigonometry_benchmark.cpp" />
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="quantities.hpp" />
diff --git a/benchmarks/trigonometry_benchmark.cpp b/benchmarks/elementary_functions_benchmark.cpp
similarity index 96%
rename from benchmarks/trigonometry_benchmark.cpp
rename to benchmarks/elementary_functions_benchmark.cpp
index 10d839c58c..3ecab2506e 100644
--- a/benchmarks/trigonometry_benchmark.cpp
+++ b/benchmarks/elementary_functions_benchmark.cpp
@@ -18,7 +18,7 @@ void BM_EvaluateElementaryFunction(benchmark::State& state) {
   using Argument = double;
 
   std::mt19937_64 random(42);
-  std::uniform_real_distribution<> uniformly_at(-1.0, 1.0);
+  std::uniform_real_distribution<> uniformly_at(-10.0, 10.0);
   Argument argument = uniformly_at(random);
 
   if constexpr (metric == Metric::Throughput) {

From 6fe311a8ffedb1f8f389358a61f52322f8966344 Mon Sep 17 00:00:00 2001
From: pleroy <pascal.h.leroy@gmail.com>
Date: Wed, 17 Apr 2024 19:44:41 +0200
Subject: [PATCH 3/4] Missing file.

---
 benchmarks/benchmarks.vcxproj.filters | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/benchmarks/benchmarks.vcxproj.filters b/benchmarks/benchmarks.vcxproj.filters
index e46445ea61..1b2d5219a1 100644
--- a/benchmarks/benchmarks.vcxproj.filters
+++ b/benchmarks/benchmarks.vcxproj.filters
@@ -86,7 +86,7 @@
     <ClCompile Include="polynomial_in_чебышёв_basis_benchmark.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
-    <ClCompile Include="trigonometry_benchmark.cpp">
+    <ClCompile Include="elementary_functions_benchmark.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
   </ItemGroup>

From 04570ffe6bec277244194eb7285cd8e432bdb41e Mon Sep 17 00:00:00 2001
From: pleroy <pascal.h.leroy@gmail.com>
Date: Wed, 17 Apr 2024 21:44:48 +0200
Subject: [PATCH 4/4] After egg's review.

---
 benchmarks/elementary_functions_benchmark.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/benchmarks/elementary_functions_benchmark.cpp b/benchmarks/elementary_functions_benchmark.cpp
index 3ecab2506e..10d839c58c 100644
--- a/benchmarks/elementary_functions_benchmark.cpp
+++ b/benchmarks/elementary_functions_benchmark.cpp
@@ -18,7 +18,7 @@ void BM_EvaluateElementaryFunction(benchmark::State& state) {
   using Argument = double;
 
   std::mt19937_64 random(42);
-  std::uniform_real_distribution<> uniformly_at(-10.0, 10.0);
+  std::uniform_real_distribution<> uniformly_at(-1.0, 1.0);
   Argument argument = uniformly_at(random);
 
   if constexpr (metric == Metric::Throughput) {