[benchmarks] Add host platform benchmarks for number, select, and switch (#15405)

tests/benchmarks/components/select/bench_select.cpp

@@ -0,0 +1,157 @@
+#include <benchmark/benchmark.h>
+
+#include "esphome/components/select/select.h"
+
+namespace esphome::benchmarks {
+
+// Inner iteration count to amortize CodSpeed instrumentation overhead.
+static constexpr int kInnerIterations = 2000;
+
+// Minimal Select for benchmarking — control() publishes directly by index.
+class BenchSelect : public select::Select {
+ public:
+  void configure(const char *name) { this->configure_entity_(name, 0x12345678, 0); }
+
+ protected:
+  void control(size_t index) override { this->publish_state(index); }
+};
+
+// Helper to create a select with the given options.
+static void setup_select(BenchSelect &select, const char *name, std::initializer_list<const char *> options) {
+  select.configure(name);
+  select.traits.set_options(options);
+  select.publish_state(size_t(0));
+}
+
+// --- Select::publish_state(size_t) ---
+// The fast path: publish by index, no string lookup.
+
+static void SelectPublish_ByIndex(benchmark::State &state) {
+  BenchSelect select;
+  setup_select(select, "test_select", {"off", "still", "move", "still+move"});
+
+  for (auto _ : state) {
+    for (int i = 0; i < kInnerIterations; i++) {
+      select.publish_state(static_cast<size_t>(i % 4));
+    }
+    benchmark::DoNotOptimize(select.active_index());
+  }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
+}
+BENCHMARK(SelectPublish_ByIndex);
+
+// --- Select::publish_state(const char *) ---
+// The string path: requires index_of() lookup via strncmp.
+
+static void SelectPublish_ByString(benchmark::State &state) {
+  BenchSelect select;
+  setup_select(select, "test_select", {"off", "still", "move", "still+move"});
+
+  const char *options[] = {"off", "still", "move", "still+move"};
+
+  for (auto _ : state) {
+    for (int i = 0; i < kInnerIterations; i++) {
+      select.publish_state(options[i % 4]);
+    }
+    benchmark::DoNotOptimize(select.active_index());
+  }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
+}
+BENCHMARK(SelectPublish_ByString);
+
+// --- Select::publish_state() with callback ---
+// Measures callback dispatch overhead on the index path.
+
+static void SelectPublish_WithCallback(benchmark::State &state) {
+  BenchSelect select;
+  setup_select(select, "test_select", {"off", "still", "move", "still+move"});
+
+  uint64_t callback_count = 0;
+  select.add_on_state_callback([&callback_count](size_t) { callback_count++; });
+
+  for (auto _ : state) {
+    for (int i = 0; i < kInnerIterations; i++) {
+      select.publish_state(static_cast<size_t>(i % 4));
+    }
+    benchmark::DoNotOptimize(callback_count);
+  }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
+}
+BENCHMARK(SelectPublish_WithCallback);
+
+// --- SelectCall::perform() set by index ---
+// The fast call path — no string matching needed.
+
+static void SelectCall_SetByIndex(benchmark::State &state) {
+  BenchSelect select;
+  setup_select(select, "test_select", {"off", "still", "move", "still+move"});
+
+  for (auto _ : state) {
+    for (int i = 0; i < kInnerIterations; i++) {
+      select.make_call().set_index(i % 4).perform();
+    }
+    benchmark::DoNotOptimize(select.active_index());
+  }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
+}
+BENCHMARK(SelectCall_SetByIndex);
+
+// --- SelectCall::perform() set by option string ---
+// Exercises the string lookup path through index_of().
+
+static void SelectCall_SetByOption(benchmark::State &state) {
+  BenchSelect select;
+  setup_select(select, "test_select", {"off", "still", "move", "still+move"});
+
+  const char *options[] = {"off", "still", "move", "still+move"};
+
+  for (auto _ : state) {
+    for (int i = 0; i < kInnerIterations; i++) {
+      select.make_call().set_option(options[i % 4]).perform();
+    }
+    benchmark::DoNotOptimize(select.active_index());
+  }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
+}
+BENCHMARK(SelectCall_SetByOption);
+
+// --- SelectCall::perform() next with cycling ---
+// Exercises the navigation path through active_index_.
+
+static void SelectCall_NextCycle(benchmark::State &state) {
+  BenchSelect select;
+  setup_select(select, "test_select", {"off", "still", "move", "still+move"});
+
+  for (auto _ : state) {
+    for (int i = 0; i < kInnerIterations; i++) {
+      select.make_call().select_next(true).perform();
+    }
+    benchmark::DoNotOptimize(select.active_index());
+  }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
+}
+BENCHMARK(SelectCall_NextCycle);
+
+// --- SelectCall with 10 options (string lookup) ---
+// Worst-case string matching with more options.
+
+static void SelectCall_SetByOption_10Options(benchmark::State &state) {
+  BenchSelect select;
+  setup_select(
+      select, "test_select",
+      {"off", "still", "move", "still+move", "custom1", "custom2", "custom3", "custom4", "custom5", "custom6"});
+
+  // Pick options spread across the list to exercise different search depths
+  const char *picks[] = {"off", "custom3", "custom6", "move"};
+
+  for (auto _ : state) {
+    for (int i = 0; i < kInnerIterations; i++) {
+      select.make_call().set_option(picks[i % 4]).perform();
+    }
+    benchmark::DoNotOptimize(select.active_index());
+  }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
+}
+BENCHMARK(SelectCall_SetByOption_10Options);
+
+}  // namespace esphome::benchmarks