Improve benchmark for StringPool

benchmark/src/benchmarks/benchmark.stringpool.cpp

@@ -1,73 +1,102 @@
 #include <benchmark/benchmark.h>
+#include <random>
 #include <zasm/core/stringpool.hpp>
 
 namespace zasm::benchmarks
 {
-    static const std::string TestStrings[] = { "hello", "world", "longer string", "even longer string",
-                                               "even longer longer string" };
+    static constexpr auto kTestSize = 500'000;
+    static constexpr const char kChars[] = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
+
+    static const std::vector<std::string> kInputStrings = []() {
+        std::vector<std::string> strings;
+
+        std::mt19937 prng(42);
+        for (int i = 0; i < kTestSize; ++i)
+        {
+            std::string str;
+            for (size_t i = 0; i < 4 + (prng() % 24); ++i)
+            {
+                str.push_back(kChars[prng() % (sizeof(kChars) - 1)]);
+            }
+            strings.push_back(std::move(str));
+        }
+        return strings;
+    }();
 
     static void BM_StringPool_Aquire(benchmark::State& state)
     {
         StringPool pool;
         for (auto _ : state)
         {
-            const auto& str = TestStrings[state.range(0)];
+            for (auto i = 0; i < state.range(0); ++i)
+            {
+                const auto& str = kInputStrings[i];
 
-            auto stringId = pool.aquire(str);
-            benchmark::DoNotOptimize(stringId);
+                auto stringId = pool.aquire(str);
+                benchmark::DoNotOptimize(stringId);
+            }
         }
     }
-    BENCHMARK(BM_StringPool_Aquire)->DenseRange(0, std::size(TestStrings) - 1);
+    BENCHMARK(BM_StringPool_Aquire)->Range(0, kTestSize)->Unit(benchmark::kMillisecond);
 
     static void BM_StringPool_Release(benchmark::State& state)
     {
         StringPool pool;
         for (auto _ : state)
         {
-            state.PauseTiming();
-            const auto& str = TestStrings[state.range(0)];
+            for (auto i = 0; i < state.range(0); ++i)
+            {
+                state.PauseTiming();
+                const auto& str = kInputStrings[i];
 
-            auto stringId = pool.aquire(str);
-            state.ResumeTiming();
+                auto stringId = pool.aquire(str);
+                state.ResumeTiming();
 
-            auto refCount = pool.release(stringId);
-            benchmark::DoNotOptimize(refCount);
+                auto refCount = pool.release(stringId);
+                benchmark::DoNotOptimize(refCount);
+            }
         }
     }
-    BENCHMARK(BM_StringPool_Release)->DenseRange(0, std::size(TestStrings) - 1);
+    BENCHMARK(BM_StringPool_Release)->Range(0, kTestSize)->Unit(benchmark::kMillisecond);
 
     static void BM_StringPool_Get(benchmark::State& state)
     {
         StringPool pool;
         for (auto _ : state)
         {
-            state.PauseTiming();
-            const auto& str = TestStrings[state.range(0)];
+            for (auto i = 0; i < state.range(0); ++i)
+            {
+                state.PauseTiming();
+                const auto& str = kInputStrings[i];
 
-            auto stringId = pool.aquire(str);
-            state.ResumeTiming();
+                auto stringId = pool.aquire(str);
+                state.ResumeTiming();
 
-            const char* res = pool.get(stringId);
-            benchmark::DoNotOptimize(res);
+                const char* res = pool.get(stringId);
+                benchmark::DoNotOptimize(res);
+            }
         }
     }
-    BENCHMARK(BM_StringPool_Get)->DenseRange(0, std::size(TestStrings) - 1);
+    BENCHMARK(BM_StringPool_Get)->Range(0, kTestSize)->Unit(benchmark::kMillisecond);
 
     static void BM_StringPool_GetLength(benchmark::State& state)
     {
         StringPool pool;
         for (auto _ : state)
         {
-            state.PauseTiming();
-            const auto& str = TestStrings[state.range(0)];
+            for (auto i = 0; i < state.range(0); ++i)
+            {
+                state.PauseTiming();
+                const auto& str = kInputStrings[i];
 
-            auto stringId = pool.aquire(str);
-            state.ResumeTiming();
+                auto stringId = pool.aquire(str);
+                state.ResumeTiming();
 
-            auto strLen = pool.getLength(stringId);
-            benchmark::DoNotOptimize(strLen);
+                auto strLen = pool.getLength(stringId);
+                benchmark::DoNotOptimize(strLen);
+            }
         }
     }
-    BENCHMARK(BM_StringPool_GetLength)->DenseRange(0, std::size(TestStrings) - 1);
+    BENCHMARK(BM_StringPool_GetLength)->Range(0, kTestSize)->Unit(benchmark::kMillisecond);
 
 } // namespace zasm::benchmarks