text: /** @file
   *****************************************************************************
  
   Implementation of functions for profiling code blocks.
  
   See profiling.hpp .
  
   *****************************************************************************
   * @author     This file is part of libsnark, developed by SCIPR Lab
   *             and contributors (see AUTHORS).
   * @copyright  MIT license (see LICENSE file)
   *****************************************************************************/
  
  #include "common/profiling.hpp"
  #include <cassert>
  #include <stdexcept>
  #include <chrono>
  #include <cstdio>
  #include <list>
  #include <vector>
  #include <ctime>
  #include "common/default_types/ec_pp.hpp"
  #include "common/utils.hpp"
  
  #ifndef NO_PROCPS
  #include <proc/readproc.h>
  #endif
  
  namespace libsnark {
  
  long long get_nsec_time()
  {
      auto timepoint = std::chrono::high_resolution_clock::now();
      return std::chrono::duration_cast<std::chrono::nanoseconds>(timepoint.time_since_epoch()).count();
  }
  
  /* Return total CPU time consumsed by all threads of the process, in nanoseconds. */
  long long get_nsec_cpu_time()
  {
      ::timespec ts;
      if ( ::clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &ts) )
          throw ::std::runtime_error("clock_gettime(CLOCK_PROCESS_CPUTIME_ID) failed");
          // If we expected this to work, don't silently ignore failures, because that would hide the problem and incur an unnecessarily system-call overhead. So if we ever observe this exception, we should probably add a suitable #ifdef .
          //TODO: clock_gettime(CLOCK_PROCESS_CPUTIME_ID) is not supported by native Windows. What about Cygwin? Should we #ifdef on CLOCK_PROCESS_CPUTIME_ID or on __linux__?
      return ts.tv_sec * 1000000000ll + ts.tv_nsec;
  }
  
  long long start_time, last_time;
  long long start_cpu_time, last_cpu_time;
  
  void start_profiling()
  {
      printf("Reset time counters for profiling\n");
  
      last_time = start_time = get_nsec_time();
      last_cpu_time = start_cpu_time = get_nsec_cpu_time();
  }
  
  std::map<std::string, size_t> invocation_counts;
  std::map<std::string, long long> enter_times;
  std::map<std::string, long long> last_times;
  std::map<std::string, long long> cumulative_times;
  //TODO: Instead of analogous maps for time and cpu_time, use a single struct-valued map
  std::map<std::string, long long> enter_cpu_times;
  std::map<std::string, long long> last_cpu_times;
  std::map<std::pair<std::string, std::string>, long long> op_counts;
  std::map<std::pair<std::string, std::string>, long long> cumulative_op_counts; // ((msg, data_point), value)
      // TODO: Convert op_counts and cumulative_op_counts from pair to structs
  size_t indentation = 0;
  
  std::vector<std::string> block_names;
  
  std::list<std::pair<std::string, long long*> > op_data_points = {
  #ifdef PROFILE_OP_COUNTS
      std::make_pair("Fradd", &Fr<default_ec_pp>::add_cnt),
      std::make_pair("Frsub", &Fr<default_ec_pp>::sub_cnt),
      std::make_pair("Frmul", &Fr<default_ec_pp>::mul_cnt),
      std::make_pair("Frinv", &Fr<default_ec_pp>::inv_cnt),
      std::make_pair("Fqadd", &Fq<default_ec_pp>::add_cnt),
      std::make_pair("Fqsub", &Fq<default_ec_pp>::sub_cnt),
      std::make_pair("Fqmul", &Fq<default_ec_pp>::mul_cnt),
      std::make_pair("Fqinv", &Fq<default_ec_pp>::inv_cnt),
      std::make_pair("G1add", &G1<default_ec_pp>::add_cnt),
      std::make_pair("G1dbl", &G1<default_ec_pp>::dbl_cnt),
      std::make_pair("G2add", &G2<default_ec_pp>::add_cnt),
      std::make_pair("G2dbl", &G2<default_ec_pp>::dbl_cnt)
  #endif
  };
  
  bool inhibit_profiling_info = false;
  bool inhibit_profiling_counters = false;
  
  void clear_profiling_counters()
  {
      invocation_counts.clear();
      last_times.clear();
      last_cpu_times.clear();
      cumulative_times.clear();
  }
  
  void print_cumulative_time_entry(const std::string &key, const long long factor)
  {
      const double total_ms = (cumulative_times.at(key) * 1e-6);
      const size_t cnt = invocation_counts.at(key);
      const double avg_ms = total_ms / cnt;
      printf("   %-45s: %12.5fms = %lld * %0.5fms (%zu invocations, %0.5fms = %lld * %0.5fms per invocation)\n", key.c_str(), total_ms, factor, total_ms/factor, cnt, avg_ms, factor, avg_ms/factor);
  }
  
  void print_cumulative_times(const long long factor)
  {
      printf("Dumping times:\n");
      for (auto& kv : cumulative_times)
      {
          print_cumulative_time_entry(kv.first, factor);
      }
  }
  
  void print_cumulative_op_counts(const bool only_fq)
  {
  #ifdef PROFILE_OP_COUNTS
      printf("Dumping operation counts:\n");
      for (auto& msg : invocation_counts)
      {
          printf("  %-45s: ", msg.first.c_str());
          bool first = true;
          for (auto& data_point : op_data_points)
          {
              if (only_fq && data_point.first.compare(0, 2, "Fq") != 0)
              {
                  continue;
              }
  
              if (!first)
              {
                  printf(", ");
              }
              printf("%-5s = %7.0f (%3zu)",
                     data_point.first.c_str(),
                     1. * cumulative_op_counts[std::make_pair(msg.first, data_point.first)] / msg.second,
                     msg.second);
              first = false;
          }
          printf("\n");
      }
  #else
      UNUSED(only_fq);
  #endif
  }
  
  void print_op_profiling(const std::string &msg)
  {
  #ifdef PROFILE_OP_COUNTS
      printf("\n");
      print_indent();
  
      printf("(opcounts) = (");
      bool first = true;
      for (std::pair<std::string, long long*> p : op_data_points)
      {
          if (!first)
          {
              printf(", ");
          }
  
          printf("%s=%lld", p.first.c_str(), *(p.second)-op_counts[std::make_pair(msg, p.first)]);
          first = false;
      }
      printf(")");
  #else
      UNUSED(msg);
  #endif
  }
  
  static void print_times_from_last_and_start(long long     now, long long     last,
                                              long long cpu_now, long long cpu_last)
  {
      long long time_from_start = now - start_time;
      long long time_from_last = now - last;
  
      long long cpu_time_from_start = cpu_now - start_cpu_time;
      long long cpu_time_from_last = cpu_now - cpu_last;
  
      if (time_from_last != 0) {
          double parallelism_from_last = 1.0 * cpu_time_from_last / time_from_last;
          printf("[%0.4fs x%0.2f]", time_from_last * 1e-9, parallelism_from_last);
      } else {
          printf("[             ]");
      }
      if (time_from_start != 0) {
          double parallelism_from_start = 1.0 * cpu_time_from_start / time_from_start;
          printf("\t(%0.4fs x%0.2f from start)", time_from_start * 1e-9, parallelism_from_start);
      }
  }
  
  void print_time(const char* msg)
  {
      if (inhibit_profiling_info)
      {
          return;
      }
  
      long long now = get_nsec_time();
      long long cpu_now = get_nsec_cpu_time();
  
      printf("%-35s\t", msg);
      print_times_from_last_and_start(now, last_time, cpu_now, last_cpu_time);
  #ifdef PROFILE_OP_COUNTS
      print_op_profiling(msg);
  #endif
      printf("\n");
  
      fflush(stdout);
      last_time = now;
      last_cpu_time = cpu_now;
  }
  
  void print_header(const char *msg)
  {
      printf("\n================================================================================\n");
      printf("%s\n", msg);
      printf("================================================================================\n\n");
  }
  
  void print_indent()
  {
      for (size_t i = 0; i < indentation; ++i)
      {
          printf("  ");
      }
  }
  
  void op_profiling_enter(const std::string &msg)
  {
      for (std::pair<std::string, long long*> p : op_data_points)
      {
          op_counts[std::make_pair(msg, p.first)] = *(p.second);
      }
  }
  
  void enter_block(const std::string &msg, const bool indent)
  {
      if (inhibit_profiling_counters)
      {
          return;
      }
  
      block_names.emplace_back(msg);
      long long t = get_nsec_time();
      enter_times[msg] = t;
      long long cpu_t = get_nsec_cpu_time();
      enter_cpu_times[msg] = cpu_t;
  
      if (inhibit_profiling_info)
      {
          return;
      }
  
  #ifdef MULTICORE
  #pragma omp critical
  #endif
      {
          op_profiling_enter(msg);
  
          print_indent();
          printf("(enter) %-35s\t", msg.c_str());
          print_times_from_last_and_start(t, t, cpu_t, cpu_t);
          printf("\n");
          fflush(stdout);
  
          if (indent)
          {
              ++indentation;
          }
      }
  }
  
  void leave_block(const std::string &msg, const bool indent)
  {
      if (inhibit_profiling_counters)
      {
          return;
      }
  
  #ifndef MULTICORE
      assert(*(--block_names.end()) == msg);
  #endif
      block_names.pop_back();
  
      ++invocation_counts[msg];
  
      long long t = get_nsec_time();
      last_times[msg] = (t - enter_times[msg]);
      cumulative_times[msg] += (t - enter_times[msg]);
  
      long long cpu_t = get_nsec_cpu_time();
      last_cpu_times[msg] = (cpu_t - enter_cpu_times[msg]);
  
  #ifdef PROFILE_OP_COUNTS
      for (std::pair<std::string, long long*> p : op_data_points)
      {
          cumulative_op_counts[std::make_pair(msg, p.first)] += *(p.second)-op_counts[std::make_pair(msg, p.first)];
      }
  #endif
  
      if (inhibit_profiling_info)
      {
          return;
      }
  
  #ifdef MULTICORE
  #pragma omp critical
  #endif
      {
          if (indent)
          {
              --indentation;
          }
  
          print_indent();
          printf("(leave) %-35s\t", msg.c_str());
          print_times_from_last_and_start(t, enter_times[msg], cpu_t, enter_cpu_times[msg]);
          print_op_profiling(msg);
          printf("\n");
          fflush(stdout);
      }
  }
  
  void print_mem(const std::string &s)
  {
  #ifndef NO_PROCPS
      struct proc_t usage;
      look_up_our_self(&usage);
      if (s.empty())
      {
          printf("* Peak vsize (physical memory+swap) in mebibytes: %lu\n", usage.vsize >> 20);
      }
      else
      {
          printf("* Peak vsize (physical memory+swap) in mebibytes (%s): %lu\n", s.c_str(), usage.vsize >> 20);
      }
  #else
      printf("* Memory profiling not supported in NO_PROCPS mode\n");
  #endif
  }
  
  void print_compilation_info()
  {
  #ifdef __GNUC__
      printf("g++ version: %s\n", __VERSION__);
      //printf("Compiled on %s %s\n", __DATE__, __TIME__);
  #endif
  #ifdef STATIC
      printf("STATIC: yes\n");
  #else
      printf("STATIC: no\n");
  #endif
  #ifdef MULTICORE
      printf("MULTICORE: yes\n");
  #else
      printf("MULTICORE: no\n");
  #endif
  #ifdef DEBUG
      printf("DEBUG: yes\n");
  #else
      printf("DEBUG: no\n");
  #endif
  #ifdef PROFILE_OP_COUNTS
      printf("PROFILE_OP_COUNTS: yes\n");
  #else
      printf("PROFILE_OP_COUNTS: no\n");
  #endif
  #ifdef _GLIBCXX_DEBUG
      printf("_GLIBCXX_DEBUG: yes\n");
  #else
      printf("_GLIBCXX_DEBUG: no\n");
  #endif
  }
  
  } // libsnark
  