diff options
Diffstat (limited to 'absl/container')
-rw-r--r-- | absl/container/inlined_vector_benchmark.cc | 37 |
1 files changed, 24 insertions, 13 deletions
diff --git a/absl/container/inlined_vector_benchmark.cc b/absl/container/inlined_vector_benchmark.cc index 5977bc93..24f21749 100644 --- a/absl/container/inlined_vector_benchmark.cc +++ b/absl/container/inlined_vector_benchmark.cc @@ -63,18 +63,34 @@ void BM_StdVectorFill(benchmark::State& state) { } BENCHMARK(BM_StdVectorFill)->Range(0, 1024); +// The purpose of the next two benchmarks is to verify that +// absl::InlinedVector is efficient when moving is more efficent than +// copying. To do so, we use strings that are larger than the short +// std::string optimization. bool StringRepresentedInline(std::string s) { const char* chars = s.data(); std::string s1 = std::move(s); return s1.data() != chars; } +int GetNonShortStringOptimizationSize() { + for (int i = 24; i <= 192; i *= 2) { + if (!StringRepresentedInline(std::string(i, 'A'))) { + return i; + } + } + ABSL_RAW_LOG( + FATAL, + "Failed to find a std::string larger than the short std::string optimization"); + return -1; +} + void BM_InlinedVectorFillString(benchmark::State& state) { const int len = state.range(0); - std::string strings[4] = {"a quite long string", - "another long string", - "012345678901234567", - "to cause allocation"}; + const int no_sso = GetNonShortStringOptimizationSize(); + std::string strings[4] = {std::string(no_sso, 'A'), std::string(no_sso, 'B'), + std::string(no_sso, 'C'), std::string(no_sso, 'D')}; + for (auto _ : state) { absl::InlinedVector<std::string, 8> v; for (int i = 0; i < len; i++) { @@ -87,10 +103,10 @@ BENCHMARK(BM_InlinedVectorFillString)->Range(0, 1024); void BM_StdVectorFillString(benchmark::State& state) { const int len = state.range(0); - std::string strings[4] = {"a quite long string", - "another long string", - "012345678901234567", - "to cause allocation"}; + const int no_sso = GetNonShortStringOptimizationSize(); + std::string strings[4] = {std::string(no_sso, 'A'), std::string(no_sso, 'B'), + std::string(no_sso, 'C'), std::string(no_sso, 'D')}; + for (auto _ : state) { std::vector<std::string> v; for (int i = 0; i < len; i++) { @@ -98,11 +114,6 @@ void BM_StdVectorFillString(benchmark::State& state) { } } state.SetItemsProcessed(static_cast<int64_t>(state.iterations()) * len); - // The purpose of the benchmark is to verify that inlined vector is - // efficient when moving is more efficent than copying. To do so, we - // use strings that are larger than the small std::string optimization. - ABSL_RAW_CHECK(!StringRepresentedInline(strings[0]), - "benchmarked with strings that are too small"); } BENCHMARK(BM_StdVectorFillString)->Range(0, 1024); |