llvm-project/libcxx/benchmarks/string.bench.cpp

50 lines
1.6 KiB
C++

#include <unordered_set>
#include <vector>
#include <cstdint>
#include "benchmark/benchmark.h"
#include "GenerateInput.hpp"
constexpr std::size_t MAX_STRING_LEN = 8 << 14;
// Benchmark when there is no match.
static void BM_StringFindNoMatch(benchmark::State &state) {
std::string s1(state.range(0), '-');
std::string s2(8, '*');
while (state.KeepRunning())
benchmark::DoNotOptimize(s1.find(s2));
}
BENCHMARK(BM_StringFindNoMatch)->Range(10, MAX_STRING_LEN);
// Benchmark when the string matches first time.
static void BM_StringFindAllMatch(benchmark::State &state) {
std::string s1(MAX_STRING_LEN, '-');
std::string s2(state.range(0), '-');
while (state.KeepRunning())
benchmark::DoNotOptimize(s1.find(s2));
}
BENCHMARK(BM_StringFindAllMatch)->Range(1, MAX_STRING_LEN);
// Benchmark when the string matches somewhere in the end.
static void BM_StringFindMatch1(benchmark::State &state) {
std::string s1(MAX_STRING_LEN / 2, '*');
s1 += std::string(state.range(0), '-');
std::string s2(state.range(0), '-');
while (state.KeepRunning())
benchmark::DoNotOptimize(s1.find(s2));
}
BENCHMARK(BM_StringFindMatch1)->Range(1, MAX_STRING_LEN / 4);
// Benchmark when the string matches somewhere from middle to the end.
static void BM_StringFindMatch2(benchmark::State &state) {
std::string s1(MAX_STRING_LEN / 2, '*');
s1 += std::string(state.range(0), '-');
s1 += std::string(state.range(0), '*');
std::string s2(state.range(0), '-');
while (state.KeepRunning())
benchmark::DoNotOptimize(s1.find(s2));
}
BENCHMARK(BM_StringFindMatch2)->Range(1, MAX_STRING_LEN / 4);
BENCHMARK_MAIN();