1 #include "benchmark/benchmark.h"
2 #include <chrono>
3 #include <thread>
4
5 #if defined(NDEBUG)
6 #undef NDEBUG
7 #endif
8 #include <cassert>
9
BM_basic(benchmark::State & state)10 void BM_basic(benchmark::State& state) {
11 for (auto _ : state) {
12 }
13 }
14
BM_basic_slow(benchmark::State & state)15 void BM_basic_slow(benchmark::State& state) {
16 std::chrono::milliseconds sleep_duration(state.range(0));
17 for (auto _ : state) {
18 std::this_thread::sleep_for(
19 std::chrono::duration_cast<std::chrono::nanoseconds>(sleep_duration));
20 }
21 }
22
23 BENCHMARK(BM_basic);
24 BENCHMARK(BM_basic)->Arg(42);
25 BENCHMARK(BM_basic_slow)->Arg(10)->Unit(benchmark::kNanosecond);
26 BENCHMARK(BM_basic_slow)->Arg(100)->Unit(benchmark::kMicrosecond);
27 BENCHMARK(BM_basic_slow)->Arg(1000)->Unit(benchmark::kMillisecond);
28 BENCHMARK(BM_basic_slow)->Arg(1000)->Unit(benchmark::kSecond);
29 BENCHMARK(BM_basic)->Range(1, 8);
30 BENCHMARK(BM_basic)->RangeMultiplier(2)->Range(1, 8);
31 BENCHMARK(BM_basic)->DenseRange(10, 15);
32 BENCHMARK(BM_basic)->Args({42, 42});
33 BENCHMARK(BM_basic)->Ranges({{64, 512}, {64, 512}});
34 BENCHMARK(BM_basic)->MinTime(0.7);
35 BENCHMARK(BM_basic)->UseRealTime();
36 BENCHMARK(BM_basic)->ThreadRange(2, 4);
37 BENCHMARK(BM_basic)->ThreadPerCpu();
38 BENCHMARK(BM_basic)->Repetitions(3);
39 BENCHMARK(BM_basic)
40 ->RangeMultiplier(std::numeric_limits<int>::max())
41 ->Range(std::numeric_limits<int64_t>::min(),
42 std::numeric_limits<int64_t>::max());
43
44 // Negative ranges
45 BENCHMARK(BM_basic)->Range(-64, -1);
46 BENCHMARK(BM_basic)->RangeMultiplier(4)->Range(-8, 8);
47 BENCHMARK(BM_basic)->DenseRange(-2, 2, 1);
48 BENCHMARK(BM_basic)->Ranges({{-64, 1}, {-8, -1}});
49
CustomArgs(benchmark::internal::Benchmark * b)50 void CustomArgs(benchmark::internal::Benchmark* b) {
51 for (int i = 0; i < 10; ++i) {
52 b->Arg(i);
53 }
54 }
55
56 BENCHMARK(BM_basic)->Apply(CustomArgs);
57
BM_explicit_iteration_count(benchmark::State & state)58 void BM_explicit_iteration_count(benchmark::State& state) {
59 // Test that benchmarks specified with an explicit iteration count are
60 // only run once.
61 static bool invoked_before = false;
62 assert(!invoked_before);
63 invoked_before = true;
64
65 // Test that the requested iteration count is respected.
66 assert(state.max_iterations == 42);
67 size_t actual_iterations = 0;
68 for (auto _ : state)
69 ++actual_iterations;
70 assert(state.iterations() == state.max_iterations);
71 assert(state.iterations() == 42);
72
73 }
74 BENCHMARK(BM_explicit_iteration_count)->Iterations(42);
75
76 BENCHMARK_MAIN();
77