encfs/vendor/github.com/google/benchmark/test/benchmark_test.cc
2020-02-28 21:12:38 +01:00

246 lines
7.1 KiB
C++

#include "benchmark/benchmark.h"
#include <assert.h>
#include <math.h>
#include <stdint.h>
#include <chrono>
#include <cstdlib>
#include <iostream>
#include <limits>
#include <list>
#include <map>
#include <mutex>
#include <set>
#include <sstream>
#include <string>
#include <thread>
#include <utility>
#include <vector>
#if defined(__GNUC__)
#define BENCHMARK_NOINLINE __attribute__((noinline))
#else
#define BENCHMARK_NOINLINE
#endif
namespace {
int BENCHMARK_NOINLINE Factorial(uint32_t n) {
return (n == 1) ? 1 : n * Factorial(n - 1);
}
double CalculatePi(int depth) {
double pi = 0.0;
for (int i = 0; i < depth; ++i) {
double numerator = static_cast<double>(((i % 2) * 2) - 1);
double denominator = static_cast<double>((2 * i) - 1);
pi += numerator / denominator;
}
return (pi - 1.0) * 4;
}
std::set<int64_t> ConstructRandomSet(int64_t size) {
std::set<int64_t> s;
for (int i = 0; i < size; ++i) s.insert(s.end(), i);
return s;
}
std::mutex test_vector_mu;
std::vector<int>* test_vector = nullptr;
} // end namespace
static void BM_Factorial(benchmark::State& state) {
int fac_42 = 0;
for (auto _ : state) fac_42 = Factorial(8);
// Prevent compiler optimizations
std::stringstream ss;
ss << fac_42;
state.SetLabel(ss.str());
}
BENCHMARK(BM_Factorial);
BENCHMARK(BM_Factorial)->UseRealTime();
static void BM_CalculatePiRange(benchmark::State& state) {
double pi = 0.0;
for (auto _ : state) pi = CalculatePi(static_cast<int>(state.range(0)));
std::stringstream ss;
ss << pi;
state.SetLabel(ss.str());
}
BENCHMARK_RANGE(BM_CalculatePiRange, 1, 1024 * 1024);
static void BM_CalculatePi(benchmark::State& state) {
static const int depth = 1024;
for (auto _ : state) {
benchmark::DoNotOptimize(CalculatePi(static_cast<int>(depth)));
}
}
BENCHMARK(BM_CalculatePi)->Threads(8);
BENCHMARK(BM_CalculatePi)->ThreadRange(1, 32);
BENCHMARK(BM_CalculatePi)->ThreadPerCpu();
static void BM_SetInsert(benchmark::State& state) {
std::set<int64_t> data;
for (auto _ : state) {
state.PauseTiming();
data = ConstructRandomSet(state.range(0));
state.ResumeTiming();
for (int j = 0; j < state.range(1); ++j) data.insert(rand());
}
state.SetItemsProcessed(state.iterations() * state.range(1));
state.SetBytesProcessed(state.iterations() * state.range(1) * sizeof(int));
}
// Test many inserts at once to reduce the total iterations needed. Otherwise, the slower,
// non-timed part of each iteration will make the benchmark take forever.
BENCHMARK(BM_SetInsert)->Ranges({{1 << 10, 8 << 10}, {128, 512}});
template <typename Container,
typename ValueType = typename Container::value_type>
static void BM_Sequential(benchmark::State& state) {
ValueType v = 42;
for (auto _ : state) {
Container c;
for (int64_t i = state.range(0); --i;) c.push_back(v);
}
const int64_t items_processed = state.iterations() * state.range(0);
state.SetItemsProcessed(items_processed);
state.SetBytesProcessed(items_processed * sizeof(v));
}
BENCHMARK_TEMPLATE2(BM_Sequential, std::vector<int>, int)
->Range(1 << 0, 1 << 10);
BENCHMARK_TEMPLATE(BM_Sequential, std::list<int>)->Range(1 << 0, 1 << 10);
// Test the variadic version of BENCHMARK_TEMPLATE in C++11 and beyond.
#ifdef BENCHMARK_HAS_CXX11
BENCHMARK_TEMPLATE(BM_Sequential, std::vector<int>, int)->Arg(512);
#endif
static void BM_StringCompare(benchmark::State& state) {
size_t len = static_cast<size_t>(state.range(0));
std::string s1(len, '-');
std::string s2(len, '-');
for (auto _ : state) benchmark::DoNotOptimize(s1.compare(s2));
}
BENCHMARK(BM_StringCompare)->Range(1, 1 << 20);
static void BM_SetupTeardown(benchmark::State& state) {
if (state.thread_index == 0) {
// No need to lock test_vector_mu here as this is running single-threaded.
test_vector = new std::vector<int>();
}
int i = 0;
for (auto _ : state) {
std::lock_guard<std::mutex> l(test_vector_mu);
if (i % 2 == 0)
test_vector->push_back(i);
else
test_vector->pop_back();
++i;
}
if (state.thread_index == 0) {
delete test_vector;
}
}
BENCHMARK(BM_SetupTeardown)->ThreadPerCpu();
static void BM_LongTest(benchmark::State& state) {
double tracker = 0.0;
for (auto _ : state) {
for (int i = 0; i < state.range(0); ++i)
benchmark::DoNotOptimize(tracker += i);
}
}
BENCHMARK(BM_LongTest)->Range(1 << 16, 1 << 28);
static void BM_ParallelMemset(benchmark::State& state) {
int64_t size = state.range(0) / static_cast<int64_t>(sizeof(int));
int thread_size = static_cast<int>(size) / state.threads;
int from = thread_size * state.thread_index;
int to = from + thread_size;
if (state.thread_index == 0) {
test_vector = new std::vector<int>(static_cast<size_t>(size));
}
for (auto _ : state) {
for (int i = from; i < to; i++) {
// No need to lock test_vector_mu as ranges
// do not overlap between threads.
benchmark::DoNotOptimize(test_vector->at(i) = 1);
}
}
if (state.thread_index == 0) {
delete test_vector;
}
}
BENCHMARK(BM_ParallelMemset)->Arg(10 << 20)->ThreadRange(1, 4);
static void BM_ManualTiming(benchmark::State& state) {
int64_t slept_for = 0;
int64_t microseconds = state.range(0);
std::chrono::duration<double, std::micro> sleep_duration{
static_cast<double>(microseconds)};
for (auto _ : state) {
auto start = std::chrono::high_resolution_clock::now();
// Simulate some useful workload with a sleep
std::this_thread::sleep_for(
std::chrono::duration_cast<std::chrono::nanoseconds>(sleep_duration));
auto end = std::chrono::high_resolution_clock::now();
auto elapsed =
std::chrono::duration_cast<std::chrono::duration<double>>(end - start);
state.SetIterationTime(elapsed.count());
slept_for += microseconds;
}
state.SetItemsProcessed(slept_for);
}
BENCHMARK(BM_ManualTiming)->Range(1, 1 << 14)->UseRealTime();
BENCHMARK(BM_ManualTiming)->Range(1, 1 << 14)->UseManualTime();
#ifdef BENCHMARK_HAS_CXX11
template <class... Args>
void BM_with_args(benchmark::State& state, Args&&...) {
for (auto _ : state) {
}
}
BENCHMARK_CAPTURE(BM_with_args, int_test, 42, 43, 44);
BENCHMARK_CAPTURE(BM_with_args, string_and_pair_test, std::string("abc"),
std::pair<int, double>(42, 3.8));
void BM_non_template_args(benchmark::State& state, int, double) {
while(state.KeepRunning()) {}
}
BENCHMARK_CAPTURE(BM_non_template_args, basic_test, 0, 0);
#endif // BENCHMARK_HAS_CXX11
static void BM_DenseThreadRanges(benchmark::State& st) {
switch (st.range(0)) {
case 1:
assert(st.threads == 1 || st.threads == 2 || st.threads == 3);
break;
case 2:
assert(st.threads == 1 || st.threads == 3 || st.threads == 4);
break;
case 3:
assert(st.threads == 5 || st.threads == 8 || st.threads == 11 ||
st.threads == 14);
break;
default:
assert(false && "Invalid test case number");
}
while (st.KeepRunning()) {
}
}
BENCHMARK(BM_DenseThreadRanges)->Arg(1)->DenseThreadRange(1, 3);
BENCHMARK(BM_DenseThreadRanges)->Arg(2)->DenseThreadRange(1, 4, 2);
BENCHMARK(BM_DenseThreadRanges)->Arg(3)->DenseThreadRange(5, 14, 3);
BENCHMARK_MAIN();