benchmark/test/options_test.cc
Eric 25acf220a4 Refactor most usages of KeepRunning to use the perfered ranged-for. (#459)
Recently the library added a new ranged-for variant of the KeepRunning
loop that is much faster. For this reason it should be preferred in all
new code.

Because a library, its documentation, and its tests should all embody
the best practices of using the library, this patch changes all but a
few usages of KeepRunning() into for (auto _ : state).

The remaining usages in the tests and documentation persist only
to document and test behavior that is different between the two formulations.

Also note that because the range-for loop requires C++11, the KeepRunning
variant has not been deprecated at this time.
2017-10-17 12:17:02 -06:00

66 lines
1.8 KiB
C++

#include "benchmark/benchmark.h"
#include <chrono>
#include <thread>
#if defined(NDEBUG)
#undef NDEBUG
#endif
#include <cassert>
void BM_basic(benchmark::State& state) {
for (auto _ : state) {
}
}
void BM_basic_slow(benchmark::State& state) {
std::chrono::milliseconds sleep_duration(state.range(0));
for (auto _ : state) {
std::this_thread::sleep_for(
std::chrono::duration_cast<std::chrono::nanoseconds>(sleep_duration));
}
}
BENCHMARK(BM_basic);
BENCHMARK(BM_basic)->Arg(42);
BENCHMARK(BM_basic_slow)->Arg(10)->Unit(benchmark::kNanosecond);
BENCHMARK(BM_basic_slow)->Arg(100)->Unit(benchmark::kMicrosecond);
BENCHMARK(BM_basic_slow)->Arg(1000)->Unit(benchmark::kMillisecond);
BENCHMARK(BM_basic)->Range(1, 8);
BENCHMARK(BM_basic)->RangeMultiplier(2)->Range(1, 8);
BENCHMARK(BM_basic)->DenseRange(10, 15);
BENCHMARK(BM_basic)->Args({42, 42});
BENCHMARK(BM_basic)->Ranges({{64, 512}, {64, 512}});
BENCHMARK(BM_basic)->MinTime(0.7);
BENCHMARK(BM_basic)->UseRealTime();
BENCHMARK(BM_basic)->ThreadRange(2, 4);
BENCHMARK(BM_basic)->ThreadPerCpu();
BENCHMARK(BM_basic)->Repetitions(3);
void CustomArgs(benchmark::internal::Benchmark* b) {
for (int i = 0; i < 10; ++i) {
b->Arg(i);
}
}
BENCHMARK(BM_basic)->Apply(CustomArgs);
void BM_explicit_iteration_count(benchmark::State& state) {
// Test that benchmarks specified with an explicit iteration count are
// only run once.
static bool invoked_before = false;
assert(!invoked_before);
invoked_before = true;
// Test that the requested iteration count is respected.
assert(state.max_iterations == 42);
size_t actual_iterations = 0;
for (auto _ : state)
++actual_iterations;
assert(state.iterations() == state.max_iterations);
assert(state.iterations() == 42);
}
BENCHMARK(BM_explicit_iteration_count)->Iterations(42);
BENCHMARK_MAIN()