StdTimer.h

// -*- tab-width: 2; indent-tabs-mode: nil; coding: utf-8-with-signature -*-
//-----------------------------------------------------------------------------
// Copyright 2000-2026 CEA (www.cea.fr) IFPEN (www.ifpenergiesnouvelles.com)
// See the top-level COPYRIGHT file for details.
// SPDX-License-Identifier: Apache-2.0
//-----------------------------------------------------------------------------
#pragma once
#include <string>
#include <map>
#include <chrono>
 
#ifdef __cpp_lib_format
#include <format>
#define HAS_FORMAT 1
#else
#define HAS_FORMAT 0
#endif
 
namespace Alien
{
class StdTimer
{
 public:
  class Sentry
  {
   public:
    Sentry(StdTimer& parent, std::string phase)
    : m_parent(parent)
    , m_phase(phase)
    {
      m_start = std::chrono::steady_clock::now();
    }
 
    virtual ~Sentry()
    {
      std::chrono::steady_clock::time_point end = std::chrono::steady_clock::now();
      std::chrono::duration<double> time_span = std::chrono::duration_cast<std::chrono::duration<double>>(end - m_start);
 
      m_parent.add(m_phase, time_span.count());
    }
 
   private:
    StdTimer& m_parent;
    std::string m_phase;
    std::chrono::steady_clock::time_point m_start;
  };
 
  StdTimer() {}
  virtual ~StdTimer() {}
 
  void reset() {
    for (auto& iter : m_counters)
      iter.second = 0. ;
  }
 
  void add(std::string const& phase, double value)
  {
    auto iter = m_counters.find(phase);
    if (iter == m_counters.end())
      m_counters[phase] = value;
    else
      iter->second += value;
  }
 
  double operator()(std::string const& phase) const
  {
    auto iter = m_counters.find(phase);
    if (iter == m_counters.end())
      return 0. ;
    else
      return iter->second ;
  }
 
  void printInfo(const std::string& msg) const
  {
    std::cout << "================================" << std::endl;
    std::cout << "PERF INFO : " << msg << std::endl;
    for (auto const& iter : m_counters) {
#if HAS_FORMAT
      std::cout << std::format("{:10}:{:.3e}\n",iter.first,iter.second);
#else
      std::cout << iter.first<<":"<<iter.second<<std::endl ;
#endif
    }
    std::cout << "================================" << std::endl;
  }
 
  void printInfo(std::ostream& out, const std::string& msg) const
  {
    out << msg << std::endl;
    out << "================================" << std::endl;
    out << "PERF INFO : " << std::endl;
    for (auto const& iter : m_counters) {
#if HAS_FORMAT
      out << std::format("{:10}:{:.3e}\n",iter.first,iter.second);
#else
      out << iter.first<<":"<<iter.second<<std::endl ;
#endif
    }
    out << "================================" << std::endl;
  }
 
 private:
  std::map<std::string, double> m_counters;
};
} // namespace Alien