Line data    Source code

       1             : // Copyright (c) 2015 The Bitcoin Core developers
       2             : // Distributed under the MIT software license, see the accompanying
       3             : // file COPYING or http://www.opensource.org/licenses/mit-license.php.
       4             : #ifndef BITCOIN_BENCH_H
       5             : #define BITCOIN_BENCH_H
       6             : 
       7             : // Simple micro-benchmarking framework; API mostly matches a subset of the Google Benchmark
       8             : // framework (see https://github.com/google/benchmark)
       9             : // Wny not use the Google Benchmark framework? Because adding Yet Another Dependency
      10             : // (that uses cmake as its build system and has lots of features we don't need) isn't
      11             : // worth it.
      12             : 
      13             : /*
      14             :  * Usage:
      15             : 
      16             : static void CODE_TO_TIME(benchmark::State& state)
      17             : {
      18             :     ... do any setup needed...
      19             :     while (state.KeepRunning()) {
      20             :        ... do stuff you want to time...
      21             :     }
      22             :     ... do any cleanup needed...
      23             : }
      24             : 
      25             : BENCHMARK(CODE_TO_TIME);
      26             : 
      27             :  */
      28             : 
      29             : 
      30             : #include <boost/function.hpp>
      31             : #include <boost/preprocessor/cat.hpp>
      32             : #include <boost/preprocessor/stringize.hpp>
      33             : #include <map>
      34             : #include <string>
      35             : 
      36             : namespace benchmark {
      37             : 
      38           0 :     class State {
      39             :         std::string name;
      40             :         double maxElapsed;
      41             :         double beginTime;
      42             :         double lastTime, minTime, maxTime;
      43             :         int64_t count;
      44             :         int64_t timeCheckCount;
      45             :     public:
      46           0 :         State(std::string _name, double _maxElapsed) : name(_name), maxElapsed(_maxElapsed), count(0) {
      47           0 :             minTime = std::numeric_limits<double>::max();
      48           0 :             maxTime = std::numeric_limits<double>::min();
      49           0 :             timeCheckCount = 1;
      50           0 :         }
      51             :         bool KeepRunning();
      52             :     };
      53             : 
      54             :     typedef boost::function<void(State&)> BenchFunction;
      55             : 
      56             :     class BenchRunner
      57             :     {
      58             :         static std::map<std::string, BenchFunction> benchmarks;
      59             : 
      60             :     public:
      61             :         BenchRunner(std::string name, BenchFunction func);
      62             : 
      63             :         static void RunAll(double elapsedTimeForOne=1.0);
      64             :     };
      65             : }
      66             : 
      67             : // BENCHMARK(foo) expands to:  benchmark::BenchRunner bench_11foo("foo", foo);
      68             : #define BENCHMARK(n) \
      69             :     benchmark::BenchRunner BOOST_PP_CAT(bench_, BOOST_PP_CAT(__LINE__, n))(BOOST_PP_STRINGIZE(n), n);
      70             : 
      71             : #endif // BITCOIN_BENCH_H