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+// 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
+//
+// http://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 <cstdint>
+#include <random>
+#include <string>
+#include <type_traits>
+#include <vector>
+
+#include "benchmark/benchmark.h"
+#include "absl/base/internal/raw_logging.h"
+#include "absl/strings/numbers.h"
+
+namespace {
+
+template <typename T>
+void BM_FastIntToBuffer(benchmark::State& state) {
+ const int inc = state.range(0);
+ char buf[absl::numbers_internal::kFastToBufferSize];
+ // Use the unsigned type to increment to take advantage of well-defined
+ // modular arithmetic.
+ typename std::make_unsigned<T>::type x = 0;
+ for (auto _ : state) {
+ absl::numbers_internal::FastIntToBuffer(static_cast<T>(x), buf);
+ x += inc;
+ }
+}
+BENCHMARK_TEMPLATE(BM_FastIntToBuffer, int32_t)->Range(0, 1 << 15);
+BENCHMARK_TEMPLATE(BM_FastIntToBuffer, int64_t)->Range(0, 1 << 30);
+
+// Creates an integer that would be printed as `num_digits` repeated 7s in the
+// given `base`. `base` must be greater than or equal to 8.
+int64_t RepeatedSevens(int num_digits, int base) {
+ ABSL_RAW_CHECK(base >= 8, "");
+ int64_t num = 7;
+ while (--num_digits) num = base * num + 7;
+ return num;
+}
+
+void BM_safe_strto32_string(benchmark::State& state) {
+ const int digits = state.range(0);
+ const int base = state.range(1);
+ std::string str(digits, '7'); // valid in octal, decimal and hex
+ int32_t value = 0;
+ for (auto _ : state) {
+ benchmark::DoNotOptimize(
+ absl::numbers_internal::safe_strto32_base(str, &value, base));
+ }
+ ABSL_RAW_CHECK(value == RepeatedSevens(digits, base), "");
+}
+BENCHMARK(BM_safe_strto32_string)
+ ->ArgPair(1, 8)
+ ->ArgPair(1, 10)
+ ->ArgPair(1, 16)
+ ->ArgPair(2, 8)
+ ->ArgPair(2, 10)
+ ->ArgPair(2, 16)
+ ->ArgPair(4, 8)
+ ->ArgPair(4, 10)
+ ->ArgPair(4, 16)
+ ->ArgPair(8, 8)
+ ->ArgPair(8, 10)
+ ->ArgPair(8, 16)
+ ->ArgPair(10, 8)
+ ->ArgPair(9, 10);
+
+void BM_safe_strto64_string(benchmark::State& state) {
+ const int digits = state.range(0);
+ const int base = state.range(1);
+ std::string str(digits, '7'); // valid in octal, decimal and hex
+ int64_t value = 0;
+ for (auto _ : state) {
+ benchmark::DoNotOptimize(
+ absl::numbers_internal::safe_strto64_base(str, &value, base));
+ }
+ ABSL_RAW_CHECK(value == RepeatedSevens(digits, base), "");
+}
+BENCHMARK(BM_safe_strto64_string)
+ ->ArgPair(1, 8)
+ ->ArgPair(1, 10)
+ ->ArgPair(1, 16)
+ ->ArgPair(2, 8)
+ ->ArgPair(2, 10)
+ ->ArgPair(2, 16)
+ ->ArgPair(4, 8)
+ ->ArgPair(4, 10)
+ ->ArgPair(4, 16)
+ ->ArgPair(8, 8)
+ ->ArgPair(8, 10)
+ ->ArgPair(8, 16)
+ ->ArgPair(16, 8)
+ ->ArgPair(16, 10)
+ ->ArgPair(16, 16);
+
+void BM_safe_strtou32_string(benchmark::State& state) {
+ const int digits = state.range(0);
+ const int base = state.range(1);
+ std::string str(digits, '7'); // valid in octal, decimal and hex
+ uint32_t value = 0;
+ for (auto _ : state) {
+ benchmark::DoNotOptimize(
+ absl::numbers_internal::safe_strtou32_base(str, &value, base));
+ }
+ ABSL_RAW_CHECK(value == RepeatedSevens(digits, base), "");
+}
+BENCHMARK(BM_safe_strtou32_string)
+ ->ArgPair(1, 8)
+ ->ArgPair(1, 10)
+ ->ArgPair(1, 16)
+ ->ArgPair(2, 8)
+ ->ArgPair(2, 10)
+ ->ArgPair(2, 16)
+ ->ArgPair(4, 8)
+ ->ArgPair(4, 10)
+ ->ArgPair(4, 16)
+ ->ArgPair(8, 8)
+ ->ArgPair(8, 10)
+ ->ArgPair(8, 16)
+ ->ArgPair(10, 8)
+ ->ArgPair(9, 10);
+
+void BM_safe_strtou64_string(benchmark::State& state) {
+ const int digits = state.range(0);
+ const int base = state.range(1);
+ std::string str(digits, '7'); // valid in octal, decimal and hex
+ uint64_t value = 0;
+ for (auto _ : state) {
+ benchmark::DoNotOptimize(
+ absl::numbers_internal::safe_strtou64_base(str, &value, base));
+ }
+ ABSL_RAW_CHECK(value == RepeatedSevens(digits, base), "");
+}
+BENCHMARK(BM_safe_strtou64_string)
+ ->ArgPair(1, 8)
+ ->ArgPair(1, 10)
+ ->ArgPair(1, 16)
+ ->ArgPair(2, 8)
+ ->ArgPair(2, 10)
+ ->ArgPair(2, 16)
+ ->ArgPair(4, 8)
+ ->ArgPair(4, 10)
+ ->ArgPair(4, 16)
+ ->ArgPair(8, 8)
+ ->ArgPair(8, 10)
+ ->ArgPair(8, 16)
+ ->ArgPair(16, 8)
+ ->ArgPair(16, 10)
+ ->ArgPair(16, 16);
+
+// Returns a vector of `num_strings` strings. Each std::string represents a
+// floating point number with `num_digits` digits before the decimal point and
+// another `num_digits` digits after.
+std::vector<std::string> MakeFloatStrings(int num_strings, int num_digits) {
+ // For convenience, use a random number generator to generate the test data.
+ // We don't actually need random properties, so use a fixed seed.
+ std::minstd_rand0 rng(1);
+ std::uniform_int_distribution<int> random_digit('0', '9');
+
+ std::vector<std::string> float_strings(num_strings);
+ for (std::string& s : float_strings) {
+ s.reserve(2 * num_digits + 1);
+ for (int i = 0; i < num_digits; ++i) {
+ s.push_back(static_cast<char>(random_digit(rng)));
+ }
+ s.push_back('.');
+ for (int i = 0; i < num_digits; ++i) {
+ s.push_back(static_cast<char>(random_digit(rng)));
+ }
+ }
+ return float_strings;
+}
+
+template <typename StringType>
+StringType GetStringAs(const std::string& s) {
+ return static_cast<StringType>(s);
+}
+template <>
+const char* GetStringAs<const char*>(const std::string& s) {
+ return s.c_str();
+}
+
+template <typename StringType>
+std::vector<StringType> GetStringsAs(const std::vector<std::string>& strings) {
+ std::vector<StringType> result;
+ result.reserve(strings.size());
+ for (const std::string& s : strings) {
+ result.push_back(GetStringAs<StringType>(s));
+ }
+ return result;
+}
+
+template <typename T>
+void BM_SimpleAtof(benchmark::State& state) {
+ const int num_strings = state.range(0);
+ const int num_digits = state.range(1);
+ std::vector<std::string> backing_strings =
+ MakeFloatStrings(num_strings, num_digits);
+ std::vector<T> inputs = GetStringsAs<T>(backing_strings);
+ float value;
+ for (auto _ : state) {
+ for (const T& input : inputs) {
+ benchmark::DoNotOptimize(absl::SimpleAtof(input, &value));
+ }
+ }
+}
+BENCHMARK_TEMPLATE(BM_SimpleAtof, absl::string_view)
+ ->ArgPair(10, 1)
+ ->ArgPair(10, 2)
+ ->ArgPair(10, 4)
+ ->ArgPair(10, 8);
+BENCHMARK_TEMPLATE(BM_SimpleAtof, const char*)
+ ->ArgPair(10, 1)
+ ->ArgPair(10, 2)
+ ->ArgPair(10, 4)
+ ->ArgPair(10, 8);
+BENCHMARK_TEMPLATE(BM_SimpleAtof, std::string)
+ ->ArgPair(10, 1)
+ ->ArgPair(10, 2)
+ ->ArgPair(10, 4)
+ ->ArgPair(10, 8);
+
+template <typename T>
+void BM_SimpleAtod(benchmark::State& state) {
+ const int num_strings = state.range(0);
+ const int num_digits = state.range(1);
+ std::vector<std::string> backing_strings =
+ MakeFloatStrings(num_strings, num_digits);
+ std::vector<T> inputs = GetStringsAs<T>(backing_strings);
+ double value;
+ for (auto _ : state) {
+ for (const T& input : inputs) {
+ benchmark::DoNotOptimize(absl::SimpleAtod(input, &value));
+ }
+ }
+}
+BENCHMARK_TEMPLATE(BM_SimpleAtod, absl::string_view)
+ ->ArgPair(10, 1)
+ ->ArgPair(10, 2)
+ ->ArgPair(10, 4)
+ ->ArgPair(10, 8);
+BENCHMARK_TEMPLATE(BM_SimpleAtod, const char*)
+ ->ArgPair(10, 1)
+ ->ArgPair(10, 2)
+ ->ArgPair(10, 4)
+ ->ArgPair(10, 8);
+BENCHMARK_TEMPLATE(BM_SimpleAtod, std::string)
+ ->ArgPair(10, 1)
+ ->ArgPair(10, 2)
+ ->ArgPair(10, 4)
+ ->ArgPair(10, 8);
+
+} // namespace