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// Copyright 2022 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
//
//
// 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 <string>
#include "absl/crc/crc32c.h"
#include "absl/crc/internal/crc32c.h"
#include "absl/memory/memory.h"
#include "absl/strings/string_view.h"
#include "benchmark/benchmark.h"
namespace {
std::string TestString(size_t len) {
std::string result;
result.reserve(len);
for (size_t i = 0; i < len; ++i) {
result.push_back(static_cast<char>(i % 256));
}
return result;
}
void BM_Calculate(benchmark::State& state) {
int len = state.range(0);
std::string data = TestString(len);
for (auto s : state) {
benchmark::DoNotOptimize(data);
absl::crc32c_t crc = absl::ComputeCrc32c(data);
benchmark::DoNotOptimize(crc);
}
}
BENCHMARK(BM_Calculate)->Arg(0)->Arg(1)->Arg(100)->Arg(10000)->Arg(500000);
void BM_Extend(benchmark::State& state) {
int len = state.range(0);
std::string extension = TestString(len);
absl::crc32c_t base = absl::crc32c_t{0xC99465AA}; // CRC32C of "Hello World"
for (auto s : state) {
benchmark::DoNotOptimize(base);
benchmark::DoNotOptimize(extension);
absl::crc32c_t crc = absl::ExtendCrc32c(base, extension);
benchmark::DoNotOptimize(crc);
}
}
BENCHMARK(BM_Extend)->Arg(0)->Arg(1)->Arg(100)->Arg(10000)->Arg(500000)->Arg(
100 * 1000 * 1000);
// Make working set >> CPU cache size to benchmark prefetches better
void BM_ExtendCacheMiss(benchmark::State& state) {
int len = state.range(0);
constexpr int total = 300 * 1000 * 1000;
std::string extension = TestString(total);
absl::crc32c_t base = absl::crc32c_t{0xC99465AA}; // CRC32C of "Hello World"
for (auto s : state) {
for (int i = 0; i < total; i += len * 2) {
benchmark::DoNotOptimize(base);
benchmark::DoNotOptimize(extension);
absl::crc32c_t crc =
absl::ExtendCrc32c(base, absl::string_view(&extension[i], len));
benchmark::DoNotOptimize(crc);
}
}
state.SetBytesProcessed(static_cast<int64_t>(state.iterations()) * total / 2);
}
BENCHMARK(BM_ExtendCacheMiss)->Arg(10)->Arg(100)->Arg(1000)->Arg(100000);
void BM_ExtendByZeroes(benchmark::State& state) {
absl::crc32c_t base = absl::crc32c_t{0xC99465AA}; // CRC32C of "Hello World"
int num_zeroes = state.range(0);
for (auto s : state) {
benchmark::DoNotOptimize(base);
absl::crc32c_t crc = absl::ExtendCrc32cByZeroes(base, num_zeroes);
benchmark::DoNotOptimize(crc);
}
}
BENCHMARK(BM_ExtendByZeroes)
->RangeMultiplier(10)
->Range(1, 1000000)
->RangeMultiplier(32)
->Range(1, 1 << 20);
void BM_UnextendByZeroes(benchmark::State& state) {
absl::crc32c_t base = absl::crc32c_t{0xdeadbeef};
int num_zeroes = state.range(0);
for (auto s : state) {
benchmark::DoNotOptimize(base);
absl::crc32c_t crc =
absl::crc_internal::UnextendCrc32cByZeroes(base, num_zeroes);
benchmark::DoNotOptimize(crc);
}
}
BENCHMARK(BM_UnextendByZeroes)
->RangeMultiplier(10)
->Range(1, 1000000)
->RangeMultiplier(32)
->Range(1, 1 << 20);
void BM_Concat(benchmark::State& state) {
int string_b_len = state.range(0);
std::string string_b = TestString(string_b_len);
// CRC32C of "Hello World"
absl::crc32c_t crc_a = absl::crc32c_t{0xC99465AA};
absl::crc32c_t crc_b = absl::ComputeCrc32c(string_b);
for (auto s : state) {
benchmark::DoNotOptimize(crc_a);
benchmark::DoNotOptimize(crc_b);
benchmark::DoNotOptimize(string_b_len);
absl::crc32c_t crc_ab = absl::ConcatCrc32c(crc_a, crc_b, string_b_len);
benchmark::DoNotOptimize(crc_ab);
}
}
BENCHMARK(BM_Concat)
->RangeMultiplier(10)
->Range(1, 1000000)
->RangeMultiplier(32)
->Range(1, 1 << 20);
void BM_Memcpy(benchmark::State& state) {
int string_len = state.range(0);
std::string source = TestString(string_len);
auto dest = absl::make_unique<char[]>(string_len);
for (auto s : state) {
benchmark::DoNotOptimize(source);
absl::crc32c_t crc =
absl::MemcpyCrc32c(dest.get(), source.data(), source.size());
benchmark::DoNotOptimize(crc);
benchmark::DoNotOptimize(dest);
benchmark::DoNotOptimize(dest.get());
benchmark::DoNotOptimize(dest[0]);
}
state.SetBytesProcessed(static_cast<int64_t>(state.iterations()) *
state.range(0));
}
BENCHMARK(BM_Memcpy)->Arg(0)->Arg(1)->Arg(100)->Arg(10000)->Arg(500000);
void BM_RemoveSuffix(benchmark::State& state) {
int full_string_len = state.range(0);
int suffix_len = state.range(1);
std::string full_string = TestString(full_string_len);
std::string suffix = full_string.substr(
full_string_len - suffix_len, full_string_len);
absl::crc32c_t full_string_crc = absl::ComputeCrc32c(full_string);
absl::crc32c_t suffix_crc = absl::ComputeCrc32c(suffix);
for (auto s : state) {
benchmark::DoNotOptimize(full_string_crc);
benchmark::DoNotOptimize(suffix_crc);
benchmark::DoNotOptimize(suffix_len);
absl::crc32c_t crc = absl::RemoveCrc32cSuffix(full_string_crc, suffix_crc,
suffix_len);
benchmark::DoNotOptimize(crc);
}
}
BENCHMARK(BM_RemoveSuffix)
->ArgPair(1, 1)
->ArgPair(100, 10)
->ArgPair(100, 100)
->ArgPair(10000, 1)
->ArgPair(10000, 100)
->ArgPair(10000, 10000)
->ArgPair(500000, 1)
->ArgPair(500000, 100)
->ArgPair(500000, 10000)
->ArgPair(500000, 500000);
} // namespace