libcxx/benchmarks/format_to_n.bench.cpp

   1 //===----------------------------------------------------------------------===//
   2 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   3 // See https://llvm.org/LICENSE.txt for license information.
   4 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   5 //
   6 //===----------------------------------------------------------------------===//
   7
   8 #include <format>
   9
  10 #include <algorithm>
  11 #include <array>
  12 #include <iterator>
  13 #include <list>
  14 #include <span>
  15 #include <string>
  16 #include <vector>
  17
  18 #include "benchmark/benchmark.h"
  19 #include "make_string.h"
  20
  21 #define CSTR(S) MAKE_CSTRING(CharT, S)
  22
  23 /*** Back inserter ***/
  24
  25 template <class Container>
  26 static void BM_format_to_n_string_back_inserter(benchmark::State& state) {
  27   using CharT = typename Container::value_type;
  28   size_t size = state.range(0);
  29   auto str    = std::basic_string<CharT>(2 * size, CharT('*'));
  30
  31   for (auto _ : state) {
  32     Container output;
  33     benchmark::DoNotOptimize(std::format_to_n(std::back_inserter(output), size, CSTR("{}"), str));
  34   }
  35   state.SetBytesProcessed(state.iterations() * size * sizeof(CharT));
  36 }
  37
  38 /*** Begin ***/
  39
  40 template <class Container>
  41 static void BM_format_to_n_string_begin(benchmark::State& state) {
  42   using CharT = typename Container::value_type;
  43   size_t size = state.range(0);
  44   auto str    = std::basic_string<CharT>(2 * size, CharT('*'));
  45
  46   Container output(size, CharT('-'));
  47   for (auto _ : state)
  48     benchmark::DoNotOptimize(std::format_to_n(std::begin(output), size, CSTR("{}"), str));
  49
  50   state.SetBytesProcessed(state.iterations() * size * sizeof(CharT));
  51 }
  52
  53 /*** Pointer ***/
  54
  55 template <class CharT>
  56 static void BM_format_to_n_string_span(benchmark::State& state) {
  57   size_t size = state.range(0);
  58   auto str    = std::basic_string<CharT>(2 * size, CharT('*'));
  59
  60   auto buffer = std::basic_string<CharT>(size, CharT('-'));
  61   std::span<CharT> output{buffer};
  62   for (auto _ : state)
  63     benchmark::DoNotOptimize(std::format_to_n(std::begin(output), size, CSTR("{}"), str));
  64
  65   state.SetBytesProcessed(state.iterations() * size * sizeof(CharT));
  66 }
  67
  68 template <class CharT>
  69 static void BM_format_to_n_string_pointer(benchmark::State& state) {
  70   size_t size = state.range(0);
  71   auto str    = std::basic_string<CharT>(2 * size, CharT('*'));
  72
  73   auto buffer   = std::basic_string<CharT>(size, CharT('-'));
  74   CharT* output = buffer.data();
  75   for (auto _ : state)
  76     benchmark::DoNotOptimize(std::format_to_n(output, size, CSTR("{}"), str));
  77
  78   state.SetBytesProcessed(state.iterations() * size * sizeof(CharT));
  79 }
  80
  81 /*** Main ***/
  82
  83 BENCHMARK_TEMPLATE(BM_format_to_n_string_back_inserter, std::string)->RangeMultiplier(2)->Range(1, 1 << 20);
  84 BENCHMARK_TEMPLATE(BM_format_to_n_string_back_inserter, std::vector<char>)->RangeMultiplier(2)->Range(1, 1 << 20);
  85 BENCHMARK_TEMPLATE(BM_format_to_n_string_back_inserter, std::list<char>)->RangeMultiplier(2)->Range(1, 1 << 20);
  86 BENCHMARK_TEMPLATE(BM_format_to_n_string_begin, std::string)->RangeMultiplier(2)->Range(1, 1 << 20);
  87 BENCHMARK_TEMPLATE(BM_format_to_n_string_begin, std::vector<char>)->RangeMultiplier(2)->Range(1, 1 << 20);
  88 BENCHMARK_TEMPLATE(BM_format_to_n_string_begin, std::list<char>)->RangeMultiplier(2)->Range(1, 1 << 20);
  89 BENCHMARK_TEMPLATE(BM_format_to_n_string_span, char)->RangeMultiplier(2)->Range(1, 1 << 20);
  90 BENCHMARK_TEMPLATE(BM_format_to_n_string_pointer, char)->RangeMultiplier(2)->Range(1, 1 << 20);
  91
  92 BENCHMARK_TEMPLATE(BM_format_to_n_string_back_inserter, std::wstring)->RangeMultiplier(2)->Range(1, 1 << 20);
  93 BENCHMARK_TEMPLATE(BM_format_to_n_string_back_inserter, std::vector<wchar_t>)->RangeMultiplier(2)->Range(1, 1 << 20);
  94 BENCHMARK_TEMPLATE(BM_format_to_n_string_back_inserter, std::list<wchar_t>)->RangeMultiplier(2)->Range(1, 1 << 20);
  95 BENCHMARK_TEMPLATE(BM_format_to_n_string_begin, std::wstring)->RangeMultiplier(2)->Range(1, 1 << 20);
  96 BENCHMARK_TEMPLATE(BM_format_to_n_string_begin, std::vector<wchar_t>)->RangeMultiplier(2)->Range(1, 1 << 20);
  97 BENCHMARK_TEMPLATE(BM_format_to_n_string_begin, std::list<wchar_t>)->RangeMultiplier(2)->Range(1, 1 << 20);
  98 BENCHMARK_TEMPLATE(BM_format_to_n_string_span, wchar_t)->RangeMultiplier(2)->Range(1, 1 << 20);
  99 BENCHMARK_TEMPLATE(BM_format_to_n_string_pointer, wchar_t)->RangeMultiplier(2)->Range(1, 1 << 20);
 100
 101 int main(int argc, char** argv) {
 102   benchmark::Initialize(&argc, argv);
 103   if (benchmark::ReportUnrecognizedArguments(argc, argv))
 104     return 1;
 105
 106   benchmark::RunSpecifiedBenchmarks();
 107 }