57 lines
1.3 KiB
C++
57 lines
1.3 KiB
C++
|
#include "benchmark/benchmark.h"
|
||
|
|
|
||
|
|
#include <cstdlib>
|
||
|
|
#include <map>
|
||
|
|
|
||
|
|
namespace {
|
||
|
|
|
||
|
|
std::map<int, int> ConstructRandomMap(int size) {
|
||
|
|
std::map<int, int> m;
|
||
|
|
for (int i = 0; i < size; ++i) {
|
||
|
|
m.insert(std::make_pair(rand() % size, rand() % size));
|
||
|
|
}
|
||
|
|
return m;
|
||
|
|
}
|
||
|
|
|
||
|
|
} // namespace
|
||
|
|
|
||
|
|
// Basic version.
|
||
|
|
static void BM_MapLookup(benchmark::State& state) {
|
||
|
|
const int size = state.range(0);
|
||
|
|
while (state.KeepRunning()) {
|
||
|
|
state.PauseTiming();
|
||
|
|
std::map<int, int> m = ConstructRandomMap(size);
|
||
|
|
state.ResumeTiming();
|
||
|
|
for (int i = 0; i < size; ++i) {
|
||
|
|
benchmark::DoNotOptimize(m.find(rand() % size));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
state.SetItemsProcessed(state.iterations() * size);
|
||
|
|
}
|
||
|
|
BENCHMARK(BM_MapLookup)->Range(1 << 3, 1 << 12);
|
||
|
|
|
||
|
|
// Using fixtures.
|
||
|
|
class MapFixture : public ::benchmark::Fixture {
|
||
|
|
public:
|
||
|
|
void SetUp(const ::benchmark::State& st) {
|
||
|
|
m = ConstructRandomMap(st.range(0));
|
||
|
|
}
|
||
|
|
|
||
|
|
void TearDown(const ::benchmark::State&) { m.clear(); }
|
||
|
|
|
||
|
|
std::map<int, int> m;
|
||
|
|
};
|
||
|
|
|
||
|
|
BENCHMARK_DEFINE_F(MapFixture, Lookup)(benchmark::State& state) {
|
||
|
|
const int size = state.range(0);
|
||
|
|
while (state.KeepRunning()) {
|
||
|
|
for (int i = 0; i < size; ++i) {
|
||
|
|
benchmark::DoNotOptimize(m.find(rand() % size));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
state.SetItemsProcessed(state.iterations() * size);
|
||
|
|
}
|
||
|
|
BENCHMARK_REGISTER_F(MapFixture, Lookup)->Range(1 << 3, 1 << 12);
|
||
|
|
|
||
|
|
BENCHMARK_MAIN()
|