statnull.h

// Copyright 2009-2021 NTESS. Under the terms
// of Contract DE-NA0003525 with NTESS, the U.S.
// Government retains certain rights in this software.
//
// Copyright (c) 2009-2021, NTESS
// All rights reserved.
//
// This file is part of the SST software package. For license
// information, see the LICENSE file in the top level directory of the
// distribution.


#ifndef _H_SST_CORE_NULL_STATISTIC_
#define _H_SST_CORE_NULL_STATISTIC_

#include "sst/core/sst_types.h"
#include "sst/core/warnmacros.h"

#include "sst/core/statapi/statbase.h"

namespace SST {
namespace Statistics {

// NOTE: When calling base class members of classes derived from
//       a templated base class.  The user must use "this->" in
//       order to call base class members (to avoid a compiler
//       error) because they are "nondependant named" and the
//       templated base class is a "dependant named".  The
//       compiler will not look in dependant named base classes
//       when looking up indepenedent names.
// See: http://www.parashift.com/c++-faq-lite/nondependent-name-lookup-members.html

/**
    \class NullStatistic

    An empty statistic place holder.

    @tparam T A template for holding the main data type of this statistic
*/
template <class T, bool B = std::is_fundamental<T>::value>
struct NullStatisticBase {};

template <class T>
struct NullStatisticBase<T,true> : public Statistic<T> {

  NullStatisticBase(BaseComponent* comp, const std::string& statName,
                    const std::string& statSubId, Params& statParams)
  : Statistic<T>(comp, statName, statSubId, statParams)
  {
      // Set the Name of this Statistic
      this->setStatisticTypeName("NULL");
  }

  void addData_impl(T UNUSED(data)) override {}

  void addData_impl_Ntimes(uint64_t UNUSED(N), T UNUSED(data)) override {}
};

template <class... Args>
struct NullStatisticBase<std::tuple<Args...>,false> : public Statistic<std::tuple<Args...>> {

  NullStatisticBase(BaseComponent* comp, const std::string& statName,
                    const std::string& statSubId, Params& statParams)
    : Statistic<std::tuple<Args...>>(comp, statName, statSubId, statParams)
  {
      // Set the Name of this Statistic
      this->setStatisticTypeName("NULL");
  }

  void addData_impl(Args... UNUSED(data)) override {}

  void addData_impl_Ntimes(uint64_t UNUSED(N), Args... UNUSED(data)) override {}
};

template <class T>
struct NullStatisticBase<T,false> : public Statistic<T> {

  NullStatisticBase(BaseComponent* comp, const std::string& statName,
                    const std::string& statSubId, Params& statParams)
  : Statistic<T>(comp, statName, statSubId, statParams)
  {
      // Set the Name of this Statistic
      this->setStatisticTypeName("NULL");
  }

  void addData_impl(T&& UNUSED(data)) override {}
  void addData_impl(const T& UNUSED(data)) override {}

  void addData_impl(uint64_t UNUSED(N), T&& UNUSED(data)) override {}
  void addData_impl(uint64_t UNUSED(N), const T& UNUSED(data)) override {}
};

template <class T>
struct NullStatistic : public NullStatisticBase<T> {

  SST_ELI_DECLARE_STATISTIC_TEMPLATE(
      NullStatistic,
      "sst",
      "NullStatistic",
      SST_ELI_ELEMENT_VERSION(1,0,0),
      "Null object it ignore all collections",
      "SST::Statistic<T>")

  NullStatistic(BaseComponent* comp, const std::string& statName,
                const std::string& statSubId, Params& statParam)
      : NullStatisticBase<T>(comp, statName, statSubId, statParam)
  {}

  ~NullStatistic(){}

  void clearStatisticData() override
  {
      // Do Nothing
  }

  void registerOutputFields(StatisticFieldsOutput* UNUSED(statOutput)) override
  {
      // Do Nothing
  }

  void outputStatisticFields(StatisticFieldsOutput* UNUSED(statOutput), bool UNUSED(EndOfSimFlag)) override
  {
      // Do Nothing
  }

  bool isReady() const override
  {
      return true;
  }

  bool isNullStatistic() const override
  {
      return true;
  }

  static bool isLoaded() {
    return loaded_;
  }
 private:
  static bool loaded_;
};

template <class T> bool NullStatistic<T>::loaded_ = true;

template <>
struct NullStatistic<void> : public Statistic<void>
{
  SST_ELI_REGISTER_DERIVED(
    Statistic<void>,
    NullStatistic<void>,
    "sst",
    "NullStatistic",
    SST_ELI_ELEMENT_VERSION(1,0,0),
    "Null statistic for custom (void) stats"
  )

  SST_ELI_INTERFACE_INFO("Statistic<void>")

  NullStatistic(BaseComponent* comp, const std::string& statName,
                    const std::string& statSubId, Params& statParams)
  : Statistic<void>(comp, statName, statSubId, statParams)
  {
      // Set the Name of this Statistic
      this->setStatisticTypeName("NULL");
  }
};


} //namespace Statistics
} //namespace SST

#endif