// Copyright 2018 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 "absl/strings/str_split.h"
#include <iterator>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <vector>
#include "benchmark/benchmark.h"
#include "absl/base/internal/raw_logging.h"
#include "absl/strings/string_view.h"
namespace {
std::string MakeTestString(int desired_length) {
static const int kAverageValueLen = 25;
std::string test(desired_length * kAverageValueLen, 'x');
for (int i = 1; i < test.size(); i += kAverageValueLen) {
test[i] = ';';
}
return test;
}
void BM_Split2StringView(benchmark::State& state) {
std::string test = MakeTestString(state.range(0));
for (auto _ : state) {
std::vector<absl::string_view> result = absl::StrSplit(test, ';');
benchmark::DoNotOptimize(result);
}
}
BENCHMARK_RANGE(BM_Split2StringView, 0, 1 << 20);
static const absl::string_view kDelimiters = ";:,.";
std::string MakeMultiDelimiterTestString(int desired_length) {
static const int kAverageValueLen = 25;
std::string test(desired_length * kAverageValueLen, 'x');
for (int i = 0; i * kAverageValueLen < test.size(); ++i) {
// Cycle through a variety of delimiters.
test[i * kAverageValueLen] = kDelimiters[i % kDelimiters.size()];
}
return test;
}
// Measure StrSplit with ByAnyChar with four delimiters to choose from.
void BM_Split2StringViewByAnyChar(benchmark::State& state) {
std::string test = MakeMultiDelimiterTestString(state.range(0));
for (auto _ : state) {
std::vector<absl::string_view> result =
absl::StrSplit(test, absl::ByAnyChar(kDelimiters));
benchmark::DoNotOptimize(result);
}
}
BENCHMARK_RANGE(BM_Split2StringViewByAnyChar, 0, 1 << 20);
void BM_Split2StringViewLifted(benchmark::State& state) {
std::string test = MakeTestString(state.range(0));
std::vector<absl::string_view> result;
for (auto _ : state) {
result = absl::StrSplit(test, ';');
}
benchmark::DoNotOptimize(result);
}
BENCHMARK_RANGE(BM_Split2StringViewLifted, 0, 1 << 20);
void BM_Split2String(benchmark::State& state) {
std::string test = MakeTestString(state.range(0));
for (auto _ : state) {
std::vector<std::string> result = absl::StrSplit(test, ';');
benchmark::DoNotOptimize(result);
}
}
BENCHMARK_RANGE(BM_Split2String, 0, 1 << 20);
// This benchmark is for comparing Split2 to Split1 (SplitStringUsing). In
// particular, this benchmark uses SkipEmpty() to match SplitStringUsing's
// behavior.
void BM_Split2SplitStringUsing(benchmark::State& state) {
std::string test = MakeTestString(state.range(0));
for (auto _ : state) {
std::vector<std::string> result =
absl::StrSplit(test, ';', absl::SkipEmpty());
benchmark::DoNotOptimize(result);
}
}
BENCHMARK_RANGE(BM_Split2SplitStringUsing, 0, 1 << 20);
void BM_SplitStringToUnorderedSet(benchmark::State& state) {
const int len = state.range(0);
std::string test(len, 'x');
for (int i = 1; i < len; i += 2) {
test[i] = ';';
}
for (auto _ : state) {
std::unordered_set<std::string> result =
absl::StrSplit(test, ':', absl::SkipEmpty());
benchmark::DoNotOptimize(result);
}
}
BENCHMARK_RANGE(BM_SplitStringToUnorderedSet, 0, 1 << 20);
void BM_SplitStringToUnorderedMap(benchmark::State& state) {
const int len = state.range(0);
std::string test(len, 'x');
for (int i = 1; i < len; i += 2) {
test[i] = ';';
}
for (auto _ : state) {
std::unordered_map<std::string, std::string> result =
absl::StrSplit(test, ':', absl::SkipEmpty());
benchmark::DoNotOptimize(result);
}
}
BENCHMARK_RANGE(BM_SplitStringToUnorderedMap, 0, 1 << 20);
void BM_SplitStringAllowEmpty(benchmark::State& state) {
const int len = state.range(0);
std::string test(len, 'x');
for (int i = 1; i < len; i += 2) {
test[i] = ';';
}
for (auto _ : state) {
std::vector<std::string> result = absl::StrSplit(test, ';');
benchmark::DoNotOptimize(result);
}
}
BENCHMARK_RANGE(BM_SplitStringAllowEmpty, 0, 1 << 20);
struct OneCharLiteral {
char operator()() const { return 'X'; }
};
struct OneCharStringLiteral {
const char* operator()() const { return "X"; }
};
template <typename DelimiterFactory>
void BM_SplitStringWithOneChar(benchmark::State& state) {
const auto delimiter = DelimiterFactory()();
std::vector<absl::string_view> pieces;
size_t v = 0;
for (auto _ : state) {
pieces = absl::StrSplit("The quick brown fox jumps over the lazy dog",
delimiter);
v += pieces.size();
}
ABSL_RAW_CHECK(v == state.iterations(), "");
}
BENCHMARK_TEMPLATE(BM_SplitStringWithOneChar, OneCharLiteral);
BENCHMARK_TEMPLATE(BM_SplitStringWithOneChar, OneCharStringLiteral);
template <typename DelimiterFactory>
void BM_SplitStringWithOneCharNoVector(benchmark::State& state) {
const auto delimiter = DelimiterFactory()();
size_t v = 0;
for (auto _ : state) {
auto splitter = absl::StrSplit(
"The quick brown fox jumps over the lazy dog", delimiter);
v += std::distance(splitter.begin(), splitter.end());
}
ABSL_RAW_CHECK(v == state.iterations(), "");
}
BENCHMARK_TEMPLATE(BM_SplitStringWithOneCharNoVector, OneCharLiteral);
BENCHMARK_TEMPLATE(BM_SplitStringWithOneCharNoVector, OneCharStringLiteral);
} // namespace
