diff options
Diffstat (limited to 'third_party/abseil_cpp/absl/flags/flag_benchmark.cc')
| -rw-r--r-- | third_party/abseil_cpp/absl/flags/flag_benchmark.cc | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/third_party/abseil_cpp/absl/flags/flag_benchmark.cc b/third_party/abseil_cpp/absl/flags/flag_benchmark.cc new file mode 100644 index 000000000000..9982b604b3b5 --- /dev/null +++ b/third_party/abseil_cpp/absl/flags/flag_benchmark.cc @@ -0,0 +1,159 @@ +// +// Copyright 2020 The Abseil Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// https://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +#include <stdint.h> + +#include <string> +#include <vector> + +#include "absl/flags/flag.h" +#include "absl/flags/marshalling.h" +#include "absl/flags/parse.h" +#include "absl/flags/reflection.h" +#include "absl/strings/string_view.h" +#include "absl/time/time.h" +#include "absl/types/optional.h" +#include "benchmark/benchmark.h" + +namespace { +using String = std::string; +using VectorOfStrings = std::vector<std::string>; +using AbslDuration = absl::Duration; + +// We do not want to take over marshalling for the types absl::optional<int>, +// absl::optional<std::string> which we do not own. Instead we introduce unique +// "aliases" to these types, which we do. +using AbslOptionalInt = absl::optional<int>; +struct OptionalInt : AbslOptionalInt { + using AbslOptionalInt::AbslOptionalInt; +}; +// Next two functions represent Abseil Flags marshalling for OptionalInt. +bool AbslParseFlag(absl::string_view src, OptionalInt* flag, + std::string* error) { + int val; + if (src.empty()) + flag->reset(); + else if (!absl::ParseFlag(src, &val, error)) + return false; + *flag = val; + return true; +} +std::string AbslUnparseFlag(const OptionalInt& flag) { + return !flag ? "" : absl::UnparseFlag(*flag); +} + +using AbslOptionalString = absl::optional<std::string>; +struct OptionalString : AbslOptionalString { + using AbslOptionalString::AbslOptionalString; +}; +// Next two functions represent Abseil Flags marshalling for OptionalString. +bool AbslParseFlag(absl::string_view src, OptionalString* flag, + std::string* error) { + std::string val; + if (src.empty()) + flag->reset(); + else if (!absl::ParseFlag(src, &val, error)) + return false; + *flag = val; + return true; +} +std::string AbslUnparseFlag(const OptionalString& flag) { + return !flag ? "" : absl::UnparseFlag(*flag); +} + +struct UDT { + UDT() = default; + UDT(const UDT&) {} + UDT& operator=(const UDT&) { return *this; } +}; +// Next two functions represent Abseil Flags marshalling for UDT. +bool AbslParseFlag(absl::string_view, UDT*, std::string*) { return true; } +std::string AbslUnparseFlag(const UDT&) { return ""; } + +} // namespace + +#define BENCHMARKED_TYPES(A) \ + A(bool) \ + A(int16_t) \ + A(uint16_t) \ + A(int32_t) \ + A(uint32_t) \ + A(int64_t) \ + A(uint64_t) \ + A(double) \ + A(float) \ + A(String) \ + A(VectorOfStrings) \ + A(OptionalInt) \ + A(OptionalString) \ + A(AbslDuration) \ + A(UDT) + +#define FLAG_DEF(T) ABSL_FLAG(T, T##_flag, {}, ""); + +BENCHMARKED_TYPES(FLAG_DEF) + +// Register thousands of flags to bloat up the size of the registry. +// This mimics real life production binaries. +#define DEFINE_FLAG_0(name) ABSL_FLAG(int, name, 0, ""); +#define DEFINE_FLAG_1(name) DEFINE_FLAG_0(name##0) DEFINE_FLAG_0(name##1) +#define DEFINE_FLAG_2(name) DEFINE_FLAG_1(name##0) DEFINE_FLAG_1(name##1) +#define DEFINE_FLAG_3(name) DEFINE_FLAG_2(name##0) DEFINE_FLAG_2(name##1) +#define DEFINE_FLAG_4(name) DEFINE_FLAG_3(name##0) DEFINE_FLAG_3(name##1) +#define DEFINE_FLAG_5(name) DEFINE_FLAG_4(name##0) DEFINE_FLAG_4(name##1) +#define DEFINE_FLAG_6(name) DEFINE_FLAG_5(name##0) DEFINE_FLAG_5(name##1) +#define DEFINE_FLAG_7(name) DEFINE_FLAG_6(name##0) DEFINE_FLAG_6(name##1) +#define DEFINE_FLAG_8(name) DEFINE_FLAG_7(name##0) DEFINE_FLAG_7(name##1) +#define DEFINE_FLAG_9(name) DEFINE_FLAG_8(name##0) DEFINE_FLAG_8(name##1) +#define DEFINE_FLAG_10(name) DEFINE_FLAG_9(name##0) DEFINE_FLAG_9(name##1) +#define DEFINE_FLAG_11(name) DEFINE_FLAG_10(name##0) DEFINE_FLAG_10(name##1) +#define DEFINE_FLAG_12(name) DEFINE_FLAG_11(name##0) DEFINE_FLAG_11(name##1) +DEFINE_FLAG_12(bloat_flag_); + +namespace { + +#define BM_GetFlag(T) \ + void BM_GetFlag_##T(benchmark::State& state) { \ + for (auto _ : state) { \ + benchmark::DoNotOptimize(absl::GetFlag(FLAGS_##T##_flag)); \ + } \ + } \ + BENCHMARK(BM_GetFlag_##T); + +BENCHMARKED_TYPES(BM_GetFlag) + +void BM_ThreadedFindCommandLineFlag(benchmark::State& state) { + char dummy[] = "dummy"; + char* argv[] = {dummy}; + // We need to ensure that flags have been parsed. That is where the registry + // is finalized. + absl::ParseCommandLine(1, argv); + + for (auto s : state) { + benchmark::DoNotOptimize( + absl::FindCommandLineFlag("bloat_flag_010101010101")); + } +} +BENCHMARK(BM_ThreadedFindCommandLineFlag)->ThreadRange(1, 16); + +} // namespace + +#define InvokeGetFlag(T) \ + T AbslInvokeGetFlag##T() { return absl::GetFlag(FLAGS_##T##_flag); } \ + int odr##T = (benchmark::DoNotOptimize(AbslInvokeGetFlag##T), 1); + +BENCHMARKED_TYPES(InvokeGetFlag) + +// To veiw disassembly use: gdb ${BINARY} -batch -ex "disassemble /s $FUNC" |