Unit testing: add facilities to check benchmark results.

This is needed for examining the values of user counters (needed
for #348). It is also needed for checking the values of standard
benchmark results like items_processed or complexities (for example,
checking the standard deviation is needed for unit testing #357
as discussed in #362).
This commit is contained in:
Joao Paulo Magalhaes 2017-04-28 15:02:27 +01:00
parent 693a43013d
commit 6452883027
3 changed files with 232 additions and 8 deletions

View File

@ -58,6 +58,79 @@ int SetSubstitutions(
// Run all output tests.
void RunOutputTests(int argc, char* argv[]);
// ========================================================================= //
// ------------------------- Results checking ------------------------------ //
// ========================================================================= //
struct ResultsCheckerEntry;
typedef std::function< void(ResultsCheckerEntry const&) > ResultsCheckFn;
// Class to test the results of a benchmark.
// It inspects the results by looking at the CSV output of a subscribed
// benchmark.
struct ResultsCheckerEntry {
std::string name;
std::map< std::string, std::string > values;
ResultsCheckFn check_fn;
// int NumThreads() const; // TODO
// double duration_real_time() const {} // TODO
// double duration_cpu_time() const {} // TODO
// get the string for a result by name, or nullptr if the name
// is not found
const std::string* Get(std::string const& entry_name) const {
auto it = values.find(entry_name);
if(it == values.end()) return nullptr;
return &it->second;
}
// get a result by name, parsed as a specific type.
// For counters, use GetCounterAs instead.
template< class T > T GetAs(std::string const& entry_name) const {
auto *sv = Get(entry_name);
CHECK(sv != nullptr && !sv->empty());
std::stringstream ss;
ss << *sv;
T out;
ss >> out;
CHECK(!ss.fail());
return out;
}
// counters are written as doubles, so they have to be read first
// as a double, and only then converted to the asked type.
template< class T > T GetCounterAs(std::string const& entry_name) const {
double dval = GetAs< double >(entry_name);
T tval = static_cast< T >(dval);
return tval;
}
};
#define _CHECK_RESULT_VALUE(entry, getfn, var_type, var_name, relationship, value) \
CONCAT(CHECK_, relationship)(entry.getfn< var_type >(var_name), (value)) \
<< "\n" << __FILE__ << ":" << __LINE__ << ": " \
<< entry.name << ": expected (" << #var_type << ")" \
<< var_name << "=" << entry.GetAs< var_type >(var_name) \
<< " to be " #relationship " to " << (value);
#define CHECK_RESULT_VALUE(entry, var_type, var_name, relationship, value) \
_CHECK_RESULT_VALUE(entry, GetAs, var_type, var_name, relationship, value)
#define CHECK_COUNTER_VALUE(entry, var_type, var_name, relationship, value) \
_CHECK_RESULT_VALUE(entry, GetCounterAs, var_type, var_name, relationship, value)
#define CHECK_BENCHMARK_RESULTS(bm_name, checker_function) \
size_t CONCAT(dummy, __LINE__) = AddChecker(bm_name, checker_function)
// Add a function to check the (CSV) results of a benchmark. These
// functions will be called only after the output was successfully
// checked.
size_t AddChecker(const char* bm_name, ResultsCheckFn fn);
// ========================================================================= //
// --------------------------- Misc Utilities ------------------------------ //
// ========================================================================= //

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@ -34,6 +34,8 @@ SubMap& GetSubstitutions() {
static std::string safe_dec_re = "[0-9]*[.]?[0-9]+([eE][-+][0-9]+)?";
static SubMap map = {
{"%float", "[0-9]*[.]?[0-9]+([eE][-+][0-9]+)?"},
// human-readable float
{"%hrfloat", "[0-9]*[.]?[0-9]+([eE][-+][0-9]+)?[kMGTPEZYmunpfazy]?"},
{"%int", "[ ]*[0-9]+"},
{" %s ", "[ ]+"},
{"%time", "[ ]*[0-9]{1,5} ns"},
@ -146,8 +148,139 @@ class TestReporter : public benchmark::BenchmarkReporter {
std::vector<benchmark::BenchmarkReporter *> reporters_;
};
}
} // end namespace internal
// ========================================================================= //
// -------------------------- Results checking ----------------------------- //
// ========================================================================= //
namespace internal {
// Utility class to manage subscribers for checking benchmark results.
// It works by parsing the CSV output to read the results.
class ResultsChecker {
public:
std::map< std::string, ResultsCheckerEntry > results;
std::vector< std::string > result_names;
void Add(const std::string& entry_name, ResultsCheckFn fn);
void CheckResults(std::stringstream& output);
private:
ResultsCheckerEntry* Find_(const std::string& entry_name);
void SetHeader_(const std::string& csv_header);
void SetValues_(const std::string& entry_csv_line);
std::vector< std::string > SplitCsv_(std::string const& line);
};
// store the static ResultsChecker in a function to prevent initialization
// order problems
ResultsChecker& GetResultsChecker() {
static ResultsChecker rc;
return rc;
}
// add a results checker for a benchmark
void ResultsChecker::Add(const std::string& entry_name, ResultsCheckFn fn) {
results[entry_name] = {entry_name, {}, fn};
}
// check the results of all subscribed benchmarks
void ResultsChecker::CheckResults(std::stringstream& output)
{
// first reset the stream to the start
{
auto start = std::ios::streampos(0);
// clear before calling tellg()
output.clear();
// seek to zero only when needed
if(output.tellg() > start) output.seekg(start);
// and just in case
output.clear();
}
// now go over every line and publish it to the ResultsChecker
std::string line;
bool on_first = true;
while (output.eof() == false) {
CHECK(output.good());
std::getline(output, line);
if (on_first) {
SetHeader_(line); // this is important
on_first = false;
continue;
}
SetValues_(line);
}
// finally we can call the subscribed check functions
for(const auto& p : results) {
CHECK(p.second.check_fn);
p.second.check_fn(p.second);
}
}
// prepare for the names in this header
void ResultsChecker::SetHeader_(const std::string& csv_header) {
result_names = SplitCsv_(csv_header);
}
// set the values for subscribed benchmarks, and silently ignore all others
void ResultsChecker::SetValues_(const std::string& entry_csv_line) {
CHECK(!result_names.empty());
auto vals = SplitCsv_(entry_csv_line);
if(vals.empty()) return;
CHECK_EQ(vals.size(), result_names.size());
ResultsCheckerEntry* entry = Find_(vals[0]);
if(!entry) return;
for (size_t i = 1, e = vals.size(); i < e; ++i) {
entry->values[result_names[i]] = vals[i];
}
}
// find a subscribed benchmark, or return null
ResultsCheckerEntry* ResultsChecker::Find_(const std::string& entry_name) {
auto it = results.find(entry_name);
if(it == results.end()) return nullptr;
return &it->second;
}
// a quick'n'dirty csv splitter (eliminating quotes)
std::vector< std::string > ResultsChecker::SplitCsv_(std::string const& line) {
std::vector< std::string > out;
if(line.empty()) return out;
if(!result_names.empty()) out.reserve(result_names.size());
size_t prev = 0, pos = line.find_first_of(','), curr = pos;
while(pos != line.npos) {
CHECK(curr > 0);
if(line[prev] == '"') ++prev;
if(line[curr-1] == '"') --curr;
out.push_back(line.substr(prev, curr-prev));
prev = pos + 1;
pos = line.find_first_of(',', pos + 1);
curr = pos;
}
curr = line.size();
if(line[prev] == '"') ++prev;
if(line[curr-1] == '"') --curr;
out.push_back(line.substr(prev, curr-prev));
return out;
}
} // end namespace internal
size_t AddChecker(const char* bm_name, ResultsCheckFn fn)
{
auto &rc = internal::GetResultsChecker();
rc.Add(bm_name, fn);
return rc.results.size();
}
// ========================================================================= //
// -------------------------- Public API Definitions------------------------ //
// ========================================================================= //
@ -237,4 +370,10 @@ void RunOutputTests(int argc, char* argv[]) {
std::cout << "\n";
}
// now that we know the output is as expected, we can dispatch
// the checks to subscribees.
auto &csv = TestCases[2];
CHECK(strcmp(csv.name, "CSVReporter") == 0); // would use == but gcc spits a warning
internal::GetResultsChecker().CheckResults(csv.out_stream);
}

View File

@ -25,7 +25,7 @@ void BM_Counters_Simple(benchmark::State& state) {
state.counters["bar"] = 2;
}
BENCHMARK(BM_Counters_Simple);//->ThreadRange(1, 32);
ADD_CASES(TC_ConsoleOut, {{"^BM_Counters_Simple %console_report bar=%float foo=%float$"}});
ADD_CASES(TC_ConsoleOut, {{"^BM_Counters_Simple %console_report bar=%hrfloat foo=%hrfloat$"}});
ADD_CASES(TC_JSONOut, {{"\"name\": \"BM_Counters_Simple\",$"},
{"\"iterations\": %int,$", MR_Next},
{"\"real_time\": %int,$", MR_Next},
@ -35,23 +35,28 @@ ADD_CASES(TC_JSONOut, {{"\"name\": \"BM_Counters_Simple\",$"},
{"\"foo\": %float$", MR_Next},
{"}", MR_Next}});
ADD_CASES(TC_CSVOut, {{"^\"BM_Counters_Simple\",%csv_report,%float,%float$"}});
CHECK_BENCHMARK_RESULTS("BM_Counters_Simple", [](ResultsCheckerEntry const& e) {
CHECK_COUNTER_VALUE(e, int, "foo", EQ, 1);
CHECK_COUNTER_VALUE(e, int, "bar", EQ, 2);
});
// ========================================================================= //
// --------------------- Counters+Items+Bytes/s Output --------------------- //
// ========================================================================= //
namespace { int num_calls1 = 0; }
void BM_Counters_WithBytesAndItemsPSec(benchmark::State& state) {
while (state.KeepRunning()) {
}
state.counters["foo"] = 1;
state.counters["bar"] = 2;
state.SetItemsProcessed(150);
state.counters["bar"] = ++num_calls1;
state.SetBytesProcessed(364);
state.SetItemsProcessed(150);
}
BENCHMARK(BM_Counters_WithBytesAndItemsPSec);//->ThreadRange(1, 32);
ADD_CASES(TC_ConsoleOut,
{{"^BM_Counters_WithBytesAndItemsPSec %console_report "
"bar=%float foo=%float +%floatB/s +%float items/s$"}});
"bar=%hrfloat foo=%hrfloat +%floatB/s +%float items/s$"}});
ADD_CASES(TC_JSONOut, {{"\"name\": \"BM_Counters_WithBytesAndItemsPSec\",$"},
{"\"iterations\": %int,$", MR_Next},
{"\"real_time\": %int,$", MR_Next},
@ -64,6 +69,13 @@ ADD_CASES(TC_JSONOut, {{"\"name\": \"BM_Counters_WithBytesAndItemsPSec\",$"},
{"}", MR_Next}});
ADD_CASES(TC_CSVOut, {{"^\"BM_Counters_WithBytesAndItemsPSec\","
"%csv_bytes_items_report,%float,%float$"}});
CHECK_BENCHMARK_RESULTS("BM_Counters_WithBytesAndItemsPSec",
[](ResultsCheckerEntry const& e) {
CHECK_COUNTER_VALUE(e, int, "foo", EQ, 1);
CHECK_COUNTER_VALUE(e, int, "bar", EQ, num_calls1);
//TODO CHECK_RESULT_VALUE(e, int, "bytes_per_second", EQ, 364 / e.duration_cpu_time());
//TODO CHECK_RESULT_VALUE(e, int, "items_per_second", EQ, 150 / e.duration_cpu_time());
});
// ========================================================================= //
// ------------------------- Rate Counters Output -------------------------- //
@ -77,7 +89,7 @@ void BM_Counters_Rate(benchmark::State& state) {
state.counters["bar"] = bm::Counter{2, bm::Counter::kIsRate};
}
BENCHMARK(BM_Counters_Rate);//->ThreadRange(1, 32);
ADD_CASES(TC_ConsoleOut, {{"^BM_Counters_Rate %console_report bar=%float foo=%float$"}});
ADD_CASES(TC_ConsoleOut, {{"^BM_Counters_Rate %console_report bar=%hrfloat foo=%hrfloat$"}});
ADD_CASES(TC_JSONOut, {{"\"name\": \"BM_Counters_Rate\",$"},
{"\"iterations\": %int,$", MR_Next},
{"\"real_time\": %int,$", MR_Next},
@ -99,7 +111,7 @@ void BM_Counters_Threads(benchmark::State& state) {
state.counters["bar"] = 2;
}
BENCHMARK(BM_Counters_Threads)->ThreadRange(1, 8);
ADD_CASES(TC_ConsoleOut, {{"^BM_Counters_Threads/threads:%int %console_report bar=%float foo=%float$"}});
ADD_CASES(TC_ConsoleOut, {{"^BM_Counters_Threads/threads:%int %console_report bar=%hrfloat foo=%hrfloat$"}});
ADD_CASES(TC_JSONOut, {{"\"name\": \"BM_Counters_Threads/threads:%int\",$"},
{"\"iterations\": %int,$", MR_Next},
{"\"real_time\": %int,$", MR_Next},
@ -122,7 +134,7 @@ void BM_Counters_AvgThreads(benchmark::State& state) {
state.counters["bar"] = bm::Counter{2, bm::Counter::kAvgThreads};
}
BENCHMARK(BM_Counters_AvgThreads)->ThreadRange(1, 8);
ADD_CASES(TC_ConsoleOut, {{"^BM_Counters_AvgThreads/threads:%int %console_report bar=%float foo=%float$"}});
ADD_CASES(TC_ConsoleOut, {{"^BM_Counters_AvgThreads/threads:%int %console_report bar=%hrfloat foo=%hrfloat$"}});
ADD_CASES(TC_JSONOut, {{"\"name\": \"BM_Counters_AvgThreads/threads:%int\",$"},
{"\"iterations\": %int,$", MR_Next},
{"\"real_time\": %int,$", MR_Next},
@ -145,7 +157,7 @@ void BM_Counters_AvgThreadsRate(benchmark::State& state) {
state.counters["bar"] = bm::Counter{2, bm::Counter::kAvgThreadsRate};
}
BENCHMARK(BM_Counters_AvgThreadsRate)->ThreadRange(1, 8);
ADD_CASES(TC_ConsoleOut, {{"^BM_Counters_AvgThreadsRate/threads:%int %console_report bar=%float foo=%float$"}});
ADD_CASES(TC_ConsoleOut, {{"^BM_Counters_AvgThreadsRate/threads:%int %console_report bar=%hrfloat foo=%hrfloat$"}});
ADD_CASES(TC_JSONOut, {{"\"name\": \"BM_Counters_AvgThreadsRate/threads:%int\",$"},
{"\"iterations\": %int,$", MR_Next},
{"\"real_time\": %int,$", MR_Next},