tvl-depot/third_party/abseil_cpp/absl/flags/flag_benchmark.cc
Vincent Ambo 543379ce45 merge(3p/abseil_cpp): Merge upstream at 'ccdbb5941'
Change-Id: I6e85fc7b5f76bba1f1eef15e600a8acb64e97ef5
2020-06-17 14:53:41 +01:00

126 lines
3.9 KiB
C++

//
// 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/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)
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)
} // 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"