src/sim/serialize.cc - public/gem5 - Git at Google

 /*
  * Copyright (c) 2015 ARM Limited
  * All rights reserved
  *
  * The license below extends only to copyright in the software and shall
  * not be construed as granting a license to any other intellectual
  * property including but not limited to intellectual property relating
  * to a hardware implementation of the functionality of the software
  * licensed hereunder.  You may use the software subject to the license
  * terms below provided that you ensure that this notice is replicated
  * unmodified and in its entirety in all distributions of the software,
  * modified or unmodified, in source code or in binary form.
  *
  * Copyright (c) 2002-2005 The Regents of The University of Michigan
  * Copyright (c) 2013 Advanced Micro Devices, Inc.
  * Copyright (c) 2013 Mark D. Hill and David A. Wood
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met: redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer;
  * redistributions in binary form must reproduce the above copyright
  * notice, this list of conditions and the following disclaimer in the
  * documentation and/or other materials provided with the distribution;
  * neither the name of the copyright holders nor the names of its
  * contributors may be used to endorse or promote products derived from
  * this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
  * Authors: Nathan Binkert
  *          Erik Hallnor
  *          Steve Reinhardt
  *          Andreas Sandberg
  */

 #include "sim/serialize.hh"

 #include <sys/stat.h>
 #include <sys/time.h>
 #include <sys/types.h>

 #include <cerrno>
 #include <fstream>
 #include <list>
 #include <string>
 #include <vector>

 #include "arch/generic/vec_reg.hh"
 #include "base/framebuffer.hh"
 #include "base/inifile.hh"
 #include "base/misc.hh"
 #include "base/output.hh"
 #include "base/str.hh"
 #include "base/trace.hh"
 #include "debug/Checkpoint.hh"
 #include "sim/eventq.hh"
 #include "sim/sim_events.hh"
 #include "sim/sim_exit.hh"
 #include "sim/sim_object.hh"

 // For stat reset hack
 #include "sim/stat_control.hh"

 using namespace std;

 //
 // The base implementations use to_number for parsing and '<<' for
 // displaying, suitable for integer types.
 //
 template <class T>
 bool
 parseParam(const string &s, T &value)
 {
     return to_number(s, value);
 }

 template <class T>
 void
 showParam(CheckpointOut &os, const T &value)
 {
     os << value;
 }

 //
 // Template specializations:
 // - char (8-bit integer)
 // - floating-point types
 // - bool
 // - string
 //

 // Treat 8-bit ints (chars) as ints on output, not as chars
 template <>
 void
 showParam(CheckpointOut &os, const char &value)
 {
     os << (int)value;
 }


 template <>
 void
 showParam(CheckpointOut &os, const signed char &value)
 {
     os << (int)value;
 }


 template <>
 void
 showParam(CheckpointOut &os, const unsigned char &value)
 {
     os << (unsigned int)value;
 }


 template <>
 bool
 parseParam(const string &s, float &value)
 {
     return to_number(s, value);
 }

 template <>
 bool
 parseParam(const string &s, double &value)
 {
     return to_number(s, value);
 }

 template <>
 bool
 parseParam(const string &s, bool &value)
 {
     return to_bool(s, value);
 }

 // Display bools as strings
 template <>
 void
 showParam(CheckpointOut &os, const bool &value)
 {
     os << (value ? "true" : "false");
 }


 // String requires no processing to speak of
 template <>
 bool
 parseParam(const string &s, string &value)
 {
     value = s;
     return true;
 }

 int Serializable::ckptMaxCount = 0;
 int Serializable::ckptCount = 0;
 int Serializable::ckptPrevCount = -1;
 std::stack<std::string> Serializable::path;

 template <class T>
 void
 paramOut(CheckpointOut &os, const string &name, const T &param)
 {
     os << name << "=";
     showParam(os, param);
     os << "\n";
 }

 template <class T>
 void
 arrayParamOut(CheckpointOut &os, const string &name, const vector<T> &param)
 {
     typename vector<T>::size_type size = param.size();
     os << name << "=";
     if (size > 0)
         showParam(os, param[0]);
     for (typename vector<T>::size_type i = 1; i < size; ++i) {
         os << " ";
         showParam(os, param[i]);
     }
     os << "\n";
 }

 template <class T>
 void
 arrayParamOut(CheckpointOut &os, const string &name, const list<T> &param)
 {
     typename list<T>::const_iterator it = param.begin();

     os << name << "=";
     if (param.size() > 0)
         showParam(os, *it);
     it++;
     while (it != param.end()) {
         os << " ";
         showParam(os, *it);
         it++;
     }
     os << "\n";
 }

 template <class T>
 void
 arrayParamOut(CheckpointOut &os, const string &name, const set<T> &param)
 {
     typename set<T>::const_iterator it = param.begin();

     os << name << "=";
     if (param.size() > 0)
         showParam(os, *it);
     it++;
     while (it != param.end()) {
         os << " ";
         showParam(os, *it);
         it++;
     }
     os << "\n";
 }

 template <class T>
 void
 paramIn(CheckpointIn &cp, const string &name, T &param)
 {
     const string &section(Serializable::currentSection());
     string str;
     if (!cp.find(section, name, str) || !parseParam(str, param)) {
         fatal("Can't unserialize '%s:%s'\n", section, name);
     }
 }

 template <class T>
 bool
 optParamIn(CheckpointIn &cp, const string &name, T &param, bool warn)
 {
     const string &section(Serializable::currentSection());
     string str;
     if (!cp.find(section, name, str) || !parseParam(str, param)) {
         if (warn)
             warn("optional parameter %s:%s not present\n", section, name);
         return false;
     } else {
         return true;
     }
 }

 template <class T>
 void
 arrayParamOut(CheckpointOut &os, const string &name,
               const T *param, unsigned size)
 {
     os << name << "=";
     if (size > 0)
         showParam(os, param[0]);
     for (unsigned i = 1; i < size; ++i) {
         os << " ";
         showParam(os, param[i]);
     }
     os << "\n";
 }


 template <class T>
 void
 arrayParamIn(CheckpointIn &cp, const string &name, T *param, unsigned size)
 {
     const string &section(Serializable::currentSection());
     string str;
     if (!cp.find(section, name, str)) {
         fatal("Can't unserialize '%s:%s'\n", section, name);
     }

     // code below stolen from VectorParam<T>::parse().
     // it would be nice to unify these somehow...

     vector<string> tokens;

     tokenize(tokens, str, ' ');

     // Need this if we were doing a vector
     // value.resize(tokens.size());

     if (tokens.size() != size) {
         fatal("Array size mismatch on %s:%s'\n", section, name);
     }

     for (vector<string>::size_type i = 0; i < tokens.size(); i++) {
         // need to parse into local variable to handle vector<bool>,
         // for which operator[] returns a special reference class
         // that's not the same as 'bool&', (since it's a packed
         // vector)
         T scalar_value;
         if (!parseParam(tokens[i], scalar_value)) {
             string err("could not parse \"");

             err += str;
             err += "\"";

             fatal(err);
         }

         // assign parsed value to vector
         param[i] = scalar_value;
     }
 }

 template <class T>
 void
 arrayParamIn(CheckpointIn &cp, const string &name, vector<T> &param)
 {
     const string &section(Serializable::currentSection());
     string str;
     if (!cp.find(section, name, str)) {
         fatal("Can't unserialize '%s:%s'\n", section, name);
     }

     // code below stolen from VectorParam<T>::parse().
     // it would be nice to unify these somehow...

     vector<string> tokens;

     tokenize(tokens, str, ' ');

     // Need this if we were doing a vector
     // value.resize(tokens.size());

     param.resize(tokens.size());

     for (vector<string>::size_type i = 0; i < tokens.size(); i++) {
         // need to parse into local variable to handle vector<bool>,
         // for which operator[] returns a special reference class
         // that's not the same as 'bool&', (since it's a packed
         // vector)
         T scalar_value;
         if (!parseParam(tokens[i], scalar_value)) {
             string err("could not parse \"");

             err += str;
             err += "\"";

             fatal(err);
         }

         // assign parsed value to vector
         param[i] = scalar_value;
     }
 }

 template <class T>
 void
 arrayParamIn(CheckpointIn &cp, const string &name, list<T> &param)
 {
     const string &section(Serializable::currentSection());
     string str;
     if (!cp.find(section, name, str)) {
         fatal("Can't unserialize '%s:%s'\n", section, name);
     }
     param.clear();

     vector<string> tokens;
     tokenize(tokens, str, ' ');

     for (vector<string>::size_type i = 0; i < tokens.size(); i++) {
         T scalar_value;
         if (!parseParam(tokens[i], scalar_value)) {
             string err("could not parse \"");

             err += str;
             err += "\"";

             fatal(err);
         }

         // assign parsed value to vector
         param.push_back(scalar_value);
     }
 }

 template <class T>
 void
 arrayParamIn(CheckpointIn &cp, const string &name, set<T> &param)
 {
     const string &section(Serializable::currentSection());
     string str;
     if (!cp.find(section, name, str)) {
         fatal("Can't unserialize '%s:%s'\n", section, name);
     }
     param.clear();

     vector<string> tokens;
     tokenize(tokens, str, ' ');

     for (vector<string>::size_type i = 0; i < tokens.size(); i++) {
         T scalar_value;
         if (!parseParam(tokens[i], scalar_value)) {
             string err("could not parse \"");

             err += str;
             err += "\"";

             fatal(err);
         }

         // assign parsed value to vector
         param.insert(scalar_value);
     }
 }


 void
 objParamIn(CheckpointIn &cp, const string &name, SimObject * &param)
 {
     const string &section(Serializable::currentSection());
     if (!cp.findObj(section, name, param)) {
         fatal("Can't unserialize '%s:%s'\n", section, name);
     }
 }


 #define INSTANTIATE_PARAM_TEMPLATES(type)                               \
     template void                                                       \
     paramOut(CheckpointOut &os, const string &name, type const &param); \
     template void                                                       \
     paramIn(CheckpointIn &cp, const string &name, type & param);        \
     template bool                                                       \
     optParamIn(CheckpointIn &cp, const string &name, type & param,      \
                bool warn);                                              \
     template void                                                       \
     arrayParamOut(CheckpointOut &os, const string &name,                \
                   type const *param, unsigned size);                    \
     template void                                                       \
     arrayParamIn(CheckpointIn &cp, const string &name,                  \
                  type *param, unsigned size);                           \
     template void                                                       \
     arrayParamOut(CheckpointOut &os, const string &name,                \
                   const vector<type> &param);                           \
     template void                                                       \
     arrayParamIn(CheckpointIn &cp, const string &name,                  \
                  vector<type> &param);                                  \
     template void                                                       \
     arrayParamOut(CheckpointOut &os, const string &name,                \
                   const list<type> &param);                             \
     template void                                                       \
     arrayParamIn(CheckpointIn &cp, const string &name,                  \
                  list<type> &param);

 INSTANTIATE_PARAM_TEMPLATES(char)
 INSTANTIATE_PARAM_TEMPLATES(signed char)
 INSTANTIATE_PARAM_TEMPLATES(unsigned char)
 INSTANTIATE_PARAM_TEMPLATES(signed short)
 INSTANTIATE_PARAM_TEMPLATES(unsigned short)
 INSTANTIATE_PARAM_TEMPLATES(signed int)
 INSTANTIATE_PARAM_TEMPLATES(unsigned int)
 INSTANTIATE_PARAM_TEMPLATES(signed long)
 INSTANTIATE_PARAM_TEMPLATES(unsigned long)
 INSTANTIATE_PARAM_TEMPLATES(signed long long)
 INSTANTIATE_PARAM_TEMPLATES(unsigned long long)
 INSTANTIATE_PARAM_TEMPLATES(bool)
 INSTANTIATE_PARAM_TEMPLATES(float)
 INSTANTIATE_PARAM_TEMPLATES(double)
 INSTANTIATE_PARAM_TEMPLATES(string)
 INSTANTIATE_PARAM_TEMPLATES(Pixel)
 INSTANTIATE_PARAM_TEMPLATES(VecRegContainer<8>)
 INSTANTIATE_PARAM_TEMPLATES(VecRegContainer<16>)

 // set is only used with strings and furthermore doesn't agree with Pixel
 template void
 arrayParamOut(CheckpointOut &, const string &, const set<string> &);
 template void
 arrayParamIn(CheckpointIn &, const string &, set<string> &);

 /////////////////////////////

 /// Container for serializing global variables (not associated with
 /// any serialized object).
 class Globals : public Serializable
 {
   public:
     Globals()
         : unserializedCurTick(0) {}

     void serialize(CheckpointOut &cp) const override;
     void unserialize(CheckpointIn &cp) override;

     Tick unserializedCurTick;
 };

 /// The one and only instance of the Globals class.
 Globals globals;

 /// The version tags for this build of the simulator, to be stored in the
 /// Globals section during serialization and compared upon unserialization.
 extern std::set<std::string> version_tags;

 void
 Globals::serialize(CheckpointOut &cp) const
 {
     paramOut(cp, "curTick", curTick());
     SERIALIZE_CONTAINER(version_tags);
 }

 void
 Globals::unserialize(CheckpointIn &cp)
 {
     paramIn(cp, "curTick", unserializedCurTick);

     const std::string &section(Serializable::currentSection());
     std::string str;
     if (!cp.find(section, "version_tags", str)) {
         warn("**********************************************************\n");
         warn("!!!! Checkpoint uses an old versioning scheme.        !!!!\n");
         warn("Run the checkpoint upgrader (util/cpt_upgrader.py) on your "
              "checkpoint\n");
         warn("**********************************************************\n");
         return;
     }

     std::set<std::string> cpt_tags;
     arrayParamIn(cp, "version_tags", cpt_tags); // UNSERIALIZE_CONTAINER

     bool err = false;
     for (const auto& t : version_tags) {
         if (cpt_tags.find(t) == cpt_tags.end()) {
             // checkpoint is missing tag that this binary has
             if (!err) {
                 warn("*****************************************************\n");
                 warn("!!!! Checkpoint is missing the following version tags:\n");
                 err = true;
             }
             warn("  %s\n", t);
         }
     }
     if (err) {
         warn("You might experience some issues when restoring and should run "
              "the checkpoint upgrader (util/cpt_upgrader.py) on your "
              "checkpoint\n");
         warn("**********************************************************\n");
     }

     err = false;
     for (const auto& t : cpt_tags) {
         if (version_tags.find(t) == version_tags.end()) {
             // gem5 binary is missing tag that this checkpoint has
             if (!err) {
                 warn("*****************************************************\n");
                 warn("!!!! gem5 is missing the following version tags:\n");
                 err = true;
             }
             warn("  %s\n", t);
         }
     }
     if (err) {
         warn("Running a checkpoint with incompatible version tags is not "
              "supported. While it might work, you may experience incorrect "
              "behavior or crashes.\n");
         warn("**********************************************************\n");
      }
 }

 Serializable::Serializable()
 {
 }

 Serializable::~Serializable()
 {
 }

 void
 Serializable::serializeSection(CheckpointOut &cp, const char *name) const
 {
     Serializable::ScopedCheckpointSection sec(cp, name);
     serialize(cp);
 }

 void
 Serializable::unserializeSection(CheckpointIn &cp, const char *name)
 {
     Serializable::ScopedCheckpointSection sec(cp, name);
     unserialize(cp);
 }

 void
 Serializable::serializeAll(const string &cpt_dir)
 {
     string dir = CheckpointIn::setDir(cpt_dir);
     if (mkdir(dir.c_str(), 0775) == -1 && errno != EEXIST)
             fatal("couldn't mkdir %s\n", dir);

     string cpt_file = dir + CheckpointIn::baseFilename;
     ofstream outstream(cpt_file.c_str());
     time_t t = time(NULL);
     if (!outstream.is_open())
         fatal("Unable to open file %s for writing\n", cpt_file.c_str());
     outstream << "## checkpoint generated: " << ctime(&t);

     globals.serializeSection(outstream, "Globals");

     SimObject::serializeAll(outstream);
 }

 void
 Serializable::unserializeGlobals(CheckpointIn &cp)
 {
     globals.unserializeSection(cp, "Globals");

     for (uint32_t i = 0; i < numMainEventQueues; ++i)
         mainEventQueue[i]->setCurTick(globals.unserializedCurTick);
 }

 Serializable::ScopedCheckpointSection::~ScopedCheckpointSection()
 {
     assert(!path.empty());
     DPRINTF(Checkpoint, "Popping: %s\n", path.top());
     path.pop();
 }

 void
 Serializable::ScopedCheckpointSection::pushName(const char *obj_name)
 {
     if (path.empty()) {
         path.push(obj_name);
     } else {
         path.push(csprintf("%s.%s", path.top(), obj_name));
     }
     DPRINTF(Checkpoint, "ScopedCheckpointSection::pushName: %s\n", obj_name);
 }

 void
 Serializable::ScopedCheckpointSection::nameOut(CheckpointOut &cp)
 {
     DPRINTF(Checkpoint, "ScopedCheckpointSection::nameOut: %s\n",
             Serializable::currentSection());
     cp << "\n[" << Serializable::currentSection() << "]\n";
 }

 void
 debug_serialize(const string &cpt_dir)
 {
     Serializable::serializeAll(cpt_dir);
 }

 const std::string &
 Serializable::currentSection()
 {
     assert(!path.empty());

     return path.top();
 }

 const char *CheckpointIn::baseFilename = "m5.cpt";

 string CheckpointIn::currentDirectory;

 string
 CheckpointIn::setDir(const string &name)
 {
     // use csprintf to insert curTick() into directory name if it
     // appears to have a format placeholder in it.
     currentDirectory = (name.find("%") != string::npos) ?
         csprintf(name, curTick()) : name;
     if (currentDirectory[currentDirectory.size() - 1] != '/')
         currentDirectory += "/";
     return currentDirectory;
 }

 string
 CheckpointIn::dir()
 {
     return currentDirectory;
 }


 CheckpointIn::CheckpointIn(const string &cpt_dir, SimObjectResolver &resolver)
     : db(new IniFile), objNameResolver(resolver), cptDir(setDir(cpt_dir))
 {
     string filename = cptDir + "/" + CheckpointIn::baseFilename;
     if (!db->load(filename)) {
         fatal("Can't load checkpoint file '%s'\n", filename);
     }
 }

 CheckpointIn::~CheckpointIn()
 {
     delete db;
 }

 bool
 CheckpointIn::entryExists(const string &section, const string &entry)
 {
     return db->entryExists(section, entry);
 }

 bool
 CheckpointIn::find(const string &section, const string &entry, string &value)
 {
     return db->find(section, entry, value);
 }


 bool
 CheckpointIn::findObj(const string &section, const string &entry,
                     SimObject *&value)
 {
     string path;

     if (!db->find(section, entry, path))
         return false;

     value = objNameResolver.resolveSimObject(path);
     return true;
 }


 bool
 CheckpointIn::sectionExists(const string &section)
 {
     return db->sectionExists(section);
 }
	/*
	* Copyright (c) 2015 ARM Limited
	* All rights reserved
	*
	* The license below extends only to copyright in the software and shall
	* not be construed as granting a license to any other intellectual
	* property including but not limited to intellectual property relating
	* to a hardware implementation of the functionality of the software
	* licensed hereunder. You may use the software subject to the license
	* terms below provided that you ensure that this notice is replicated
	* unmodified and in its entirety in all distributions of the software,
	* modified or unmodified, in source code or in binary form.
	*
	* Copyright (c) 2002-2005 The Regents of The University of Michigan
	* Copyright (c) 2013 Advanced Micro Devices, Inc.
	* Copyright (c) 2013 Mark D. Hill and David A. Wood
	* All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions are
	* met: redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer;
	* redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution;
	* neither the name of the copyright holders nor the names of its
	* contributors may be used to endorse or promote products derived from
	* this software without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*
	* Authors: Nathan Binkert
	* Erik Hallnor
	* Steve Reinhardt
	* Andreas Sandberg
	*/

	#include "sim/serialize.hh"

	#include <sys/stat.h>
	#include <sys/time.h>
	#include <sys/types.h>

	#include <cerrno>
	#include <fstream>
	#include <list>
	#include <string>
	#include <vector>

	#include "arch/generic/vec_reg.hh"
	#include "base/framebuffer.hh"
	#include "base/inifile.hh"
	#include "base/misc.hh"
	#include "base/output.hh"
	#include "base/str.hh"
	#include "base/trace.hh"
	#include "debug/Checkpoint.hh"
	#include "sim/eventq.hh"
	#include "sim/sim_events.hh"
	#include "sim/sim_exit.hh"
	#include "sim/sim_object.hh"

	// For stat reset hack
	#include "sim/stat_control.hh"

	using namespace std;

	//
	// The base implementations use to_number for parsing and '<<' for
	// displaying, suitable for integer types.
	//
	template <class T>
	bool
	parseParam(const string &s, T &value)
	{
	return to_number(s, value);
	}

	template <class T>
	void
	showParam(CheckpointOut &os, const T &value)
	{
	os << value;
	}

	//
	// Template specializations:
	// - char (8-bit integer)
	// - floating-point types
	// - bool
	// - string
	//

	// Treat 8-bit ints (chars) as ints on output, not as chars
	template <>
	void
	showParam(CheckpointOut &os, const char &value)
	{
	os << (int)value;
	}


	template <>
	void
	showParam(CheckpointOut &os, const signed char &value)
	{
	os << (int)value;
	}


	template <>
	void
	showParam(CheckpointOut &os, const unsigned char &value)
	{
	os << (unsigned int)value;
	}


	template <>
	bool
	parseParam(const string &s, float &value)
	{
	return to_number(s, value);
	}

	template <>
	bool
	parseParam(const string &s, double &value)
	{
	return to_number(s, value);
	}

	template <>
	bool
	parseParam(const string &s, bool &value)
	{
	return to_bool(s, value);
	}

	// Display bools as strings
	template <>
	void
	showParam(CheckpointOut &os, const bool &value)
	{
	os << (value ? "true" : "false");
	}


	// String requires no processing to speak of
	template <>
	bool
	parseParam(const string &s, string &value)
	{
	value = s;
	return true;
	}

	int Serializable::ckptMaxCount = 0;
	int Serializable::ckptCount = 0;
	int Serializable::ckptPrevCount = -1;
	std::stack<std::string> Serializable::path;

	template <class T>
	void
	paramOut(CheckpointOut &os, const string &name, const T &param)
	{
	os << name << "=";
	showParam(os, param);
	os << "\n";
	}

	template <class T>
	void
	arrayParamOut(CheckpointOut &os, const string &name, const vector<T> &param)
	{
	typename vector<T>::size_type size = param.size();
	os << name << "=";
	if (size > 0)
	showParam(os, param[0]);
	for (typename vector<T>::size_type i = 1; i < size; ++i) {
	os << " ";
	showParam(os, param[i]);
	}
	os << "\n";
	}

	template <class T>
	void
	arrayParamOut(CheckpointOut &os, const string &name, const list<T> &param)
	{
	typename list<T>::const_iterator it = param.begin();

	os << name << "=";
	if (param.size() > 0)
	showParam(os, *it);
	it++;
	while (it != param.end()) {
	os << " ";
	showParam(os, *it);
	it++;
	}
	os << "\n";
	}

	template <class T>
	void
	arrayParamOut(CheckpointOut &os, const string &name, const set<T> &param)
	{
	typename set<T>::const_iterator it = param.begin();

	os << name << "=";
	if (param.size() > 0)
	showParam(os, *it);
	it++;
	while (it != param.end()) {
	os << " ";
	showParam(os, *it);
	it++;
	}
	os << "\n";
	}

	template <class T>
	void
	paramIn(CheckpointIn &cp, const string &name, T &param)
	{
	const string &section(Serializable::currentSection());
	string str;
	if (!cp.find(section, name, str) \|\| !parseParam(str, param)) {
	fatal("Can't unserialize '%s:%s'\n", section, name);
	}
	}

	template <class T>
	bool
	optParamIn(CheckpointIn &cp, const string &name, T &param, bool warn)
	{
	const string &section(Serializable::currentSection());
	string str;
	if (!cp.find(section, name, str) \|\| !parseParam(str, param)) {
	if (warn)
	warn("optional parameter %s:%s not present\n", section, name);
	return false;
	} else {
	return true;
	}
	}

	template <class T>
	void
	arrayParamOut(CheckpointOut &os, const string &name,
	const T *param, unsigned size)
	{
	os << name << "=";
	if (size > 0)
	showParam(os, param[0]);
	for (unsigned i = 1; i < size; ++i) {
	os << " ";
	showParam(os, param[i]);
	}
	os << "\n";
	}


	template <class T>
	void
	arrayParamIn(CheckpointIn &cp, const string &name, T *param, unsigned size)
	{
	const string &section(Serializable::currentSection());
	string str;
	if (!cp.find(section, name, str)) {
	fatal("Can't unserialize '%s:%s'\n", section, name);
	}

	// code below stolen from VectorParam<T>::parse().
	// it would be nice to unify these somehow...

	vector<string> tokens;

	tokenize(tokens, str, ' ');

	// Need this if we were doing a vector
	// value.resize(tokens.size());

	if (tokens.size() != size) {
	fatal("Array size mismatch on %s:%s'\n", section, name);
	}

	for (vector<string>::size_type i = 0; i < tokens.size(); i++) {
	// need to parse into local variable to handle vector<bool>,
	// for which operator[] returns a special reference class
	// that's not the same as 'bool&', (since it's a packed
	// vector)
	T scalar_value;
	if (!parseParam(tokens[i], scalar_value)) {
	string err("could not parse \"");

	err += str;
	err += "\"";

	fatal(err);
	}

	// assign parsed value to vector
	param[i] = scalar_value;
	}
	}

	template <class T>
	void
	arrayParamIn(CheckpointIn &cp, const string &name, vector<T> &param)
	{
	const string &section(Serializable::currentSection());
	string str;
	if (!cp.find(section, name, str)) {
	fatal("Can't unserialize '%s:%s'\n", section, name);
	}

	// code below stolen from VectorParam<T>::parse().
	// it would be nice to unify these somehow...

	vector<string> tokens;

	tokenize(tokens, str, ' ');

	// Need this if we were doing a vector
	// value.resize(tokens.size());

	param.resize(tokens.size());

	for (vector<string>::size_type i = 0; i < tokens.size(); i++) {
	// need to parse into local variable to handle vector<bool>,
	// for which operator[] returns a special reference class
	// that's not the same as 'bool&', (since it's a packed
	// vector)
	T scalar_value;
	if (!parseParam(tokens[i], scalar_value)) {
	string err("could not parse \"");

	err += str;
	err += "\"";

	fatal(err);
	}

	// assign parsed value to vector
	param[i] = scalar_value;
	}
	}

	template <class T>
	void
	arrayParamIn(CheckpointIn &cp, const string &name, list<T> &param)
	{
	const string &section(Serializable::currentSection());
	string str;
	if (!cp.find(section, name, str)) {
	fatal("Can't unserialize '%s:%s'\n", section, name);
	}
	param.clear();

	vector<string> tokens;
	tokenize(tokens, str, ' ');

	for (vector<string>::size_type i = 0; i < tokens.size(); i++) {
	T scalar_value;
	if (!parseParam(tokens[i], scalar_value)) {
	string err("could not parse \"");

	err += str;
	err += "\"";

	fatal(err);
	}

	// assign parsed value to vector
	param.push_back(scalar_value);
	}
	}

	template <class T>
	void
	arrayParamIn(CheckpointIn &cp, const string &name, set<T> &param)
	{
	const string &section(Serializable::currentSection());
	string str;
	if (!cp.find(section, name, str)) {
	fatal("Can't unserialize '%s:%s'\n", section, name);
	}
	param.clear();

	vector<string> tokens;
	tokenize(tokens, str, ' ');

	for (vector<string>::size_type i = 0; i < tokens.size(); i++) {
	T scalar_value;
	if (!parseParam(tokens[i], scalar_value)) {
	string err("could not parse \"");

	err += str;
	err += "\"";

	fatal(err);
	}

	// assign parsed value to vector
	param.insert(scalar_value);
	}
	}


	void
	objParamIn(CheckpointIn &cp, const string &name, SimObject * &param)
	{
	const string &section(Serializable::currentSection());
	if (!cp.findObj(section, name, param)) {
	fatal("Can't unserialize '%s:%s'\n", section, name);
	}
	}


	#define INSTANTIATE_PARAM_TEMPLATES(type) \
	template void \
	paramOut(CheckpointOut &os, const string &name, type const &param); \
	template void \
	paramIn(CheckpointIn &cp, const string &name, type & param); \
	template bool \
	optParamIn(CheckpointIn &cp, const string &name, type & param, \
	bool warn); \
	template void \
	arrayParamOut(CheckpointOut &os, const string &name, \
	type const *param, unsigned size); \
	template void \
	arrayParamIn(CheckpointIn &cp, const string &name, \
	type *param, unsigned size); \
	template void \
	arrayParamOut(CheckpointOut &os, const string &name, \
	const vector<type> &param); \
	template void \
	arrayParamIn(CheckpointIn &cp, const string &name, \
	vector<type> &param); \
	template void \
	arrayParamOut(CheckpointOut &os, const string &name, \
	const list<type> &param); \
	template void \
	arrayParamIn(CheckpointIn &cp, const string &name, \
	list<type> &param);

	INSTANTIATE_PARAM_TEMPLATES(char)
	INSTANTIATE_PARAM_TEMPLATES(signed char)
	INSTANTIATE_PARAM_TEMPLATES(unsigned char)
	INSTANTIATE_PARAM_TEMPLATES(signed short)
	INSTANTIATE_PARAM_TEMPLATES(unsigned short)
	INSTANTIATE_PARAM_TEMPLATES(signed int)
	INSTANTIATE_PARAM_TEMPLATES(unsigned int)
	INSTANTIATE_PARAM_TEMPLATES(signed long)
	INSTANTIATE_PARAM_TEMPLATES(unsigned long)
	INSTANTIATE_PARAM_TEMPLATES(signed long long)
	INSTANTIATE_PARAM_TEMPLATES(unsigned long long)
	INSTANTIATE_PARAM_TEMPLATES(bool)
	INSTANTIATE_PARAM_TEMPLATES(float)
	INSTANTIATE_PARAM_TEMPLATES(double)
	INSTANTIATE_PARAM_TEMPLATES(string)
	INSTANTIATE_PARAM_TEMPLATES(Pixel)
	INSTANTIATE_PARAM_TEMPLATES(VecRegContainer<8>)
	INSTANTIATE_PARAM_TEMPLATES(VecRegContainer<16>)

	// set is only used with strings and furthermore doesn't agree with Pixel
	template void
	arrayParamOut(CheckpointOut &, const string &, const set<string> &);
	template void
	arrayParamIn(CheckpointIn &, const string &, set<string> &);

	/////////////////////////////

	/// Container for serializing global variables (not associated with
	/// any serialized object).
	class Globals : public Serializable
	{
	public:
	Globals()
	: unserializedCurTick(0) {}

	void serialize(CheckpointOut &cp) const override;
	void unserialize(CheckpointIn &cp) override;

	Tick unserializedCurTick;
	};

	/// The one and only instance of the Globals class.
	Globals globals;

	/// The version tags for this build of the simulator, to be stored in the
	/// Globals section during serialization and compared upon unserialization.
	extern std::set<std::string> version_tags;

	void
	Globals::serialize(CheckpointOut &cp) const
	{
	paramOut(cp, "curTick", curTick());
	SERIALIZE_CONTAINER(version_tags);
	}

	void
	Globals::unserialize(CheckpointIn &cp)
	{
	paramIn(cp, "curTick", unserializedCurTick);

	const std::string &section(Serializable::currentSection());
	std::string str;
	if (!cp.find(section, "version_tags", str)) {
	warn("**********************************************************\n");
	warn("!!!! Checkpoint uses an old versioning scheme. !!!!\n");
	warn("Run the checkpoint upgrader (util/cpt_upgrader.py) on your "
	"checkpoint\n");
	warn("**********************************************************\n");
	return;
	}

	std::set<std::string> cpt_tags;
	arrayParamIn(cp, "version_tags", cpt_tags); // UNSERIALIZE_CONTAINER

	bool err = false;
	for (const auto& t : version_tags) {
	if (cpt_tags.find(t) == cpt_tags.end()) {
	// checkpoint is missing tag that this binary has
	if (!err) {
	warn("*****************************************************\n");
	warn("!!!! Checkpoint is missing the following version tags:\n");
	err = true;
	}
	warn(" %s\n", t);
	}
	}
	if (err) {
	warn("You might experience some issues when restoring and should run "
	"the checkpoint upgrader (util/cpt_upgrader.py) on your "
	"checkpoint\n");
	warn("**********************************************************\n");
	}

	err = false;
	for (const auto& t : cpt_tags) {
	if (version_tags.find(t) == version_tags.end()) {
	// gem5 binary is missing tag that this checkpoint has
	if (!err) {
	warn("*****************************************************\n");
	warn("!!!! gem5 is missing the following version tags:\n");
	err = true;
	}
	warn(" %s\n", t);
	}
	}
	if (err) {
	warn("Running a checkpoint with incompatible version tags is not "
	"supported. While it might work, you may experience incorrect "
	"behavior or crashes.\n");
	warn("**********************************************************\n");
	}
	}

	Serializable::Serializable()
	{
	}

	Serializable::~Serializable()
	{
	}

	void
	Serializable::serializeSection(CheckpointOut &cp, const char *name) const
	{
	Serializable::ScopedCheckpointSection sec(cp, name);
	serialize(cp);
	}

	void
	Serializable::unserializeSection(CheckpointIn &cp, const char *name)
	{
	Serializable::ScopedCheckpointSection sec(cp, name);
	unserialize(cp);
	}

	void
	Serializable::serializeAll(const string &cpt_dir)
	{
	string dir = CheckpointIn::setDir(cpt_dir);
	if (mkdir(dir.c_str(), 0775) == -1 && errno != EEXIST)
	fatal("couldn't mkdir %s\n", dir);

	string cpt_file = dir + CheckpointIn::baseFilename;
	ofstream outstream(cpt_file.c_str());
	time_t t = time(NULL);
	if (!outstream.is_open())
	fatal("Unable to open file %s for writing\n", cpt_file.c_str());
	outstream << "## checkpoint generated: " << ctime(&t);

	globals.serializeSection(outstream, "Globals");

	SimObject::serializeAll(outstream);
	}

	void
	Serializable::unserializeGlobals(CheckpointIn &cp)
	{
	globals.unserializeSection(cp, "Globals");

	for (uint32_t i = 0; i < numMainEventQueues; ++i)
	mainEventQueue[i]->setCurTick(globals.unserializedCurTick);
	}

	Serializable::ScopedCheckpointSection::~ScopedCheckpointSection()
	{
	assert(!path.empty());
	DPRINTF(Checkpoint, "Popping: %s\n", path.top());
	path.pop();
	}

	void
	Serializable::ScopedCheckpointSection::pushName(const char *obj_name)
	{
	if (path.empty()) {
	path.push(obj_name);
	} else {
	path.push(csprintf("%s.%s", path.top(), obj_name));
	}
	DPRINTF(Checkpoint, "ScopedCheckpointSection::pushName: %s\n", obj_name);
	}

	void
	Serializable::ScopedCheckpointSection::nameOut(CheckpointOut &cp)
	{
	DPRINTF(Checkpoint, "ScopedCheckpointSection::nameOut: %s\n",
	Serializable::currentSection());
	cp << "\n[" << Serializable::currentSection() << "]\n";
	}

	void
	debug_serialize(const string &cpt_dir)
	{
	Serializable::serializeAll(cpt_dir);
	}

	const std::string &
	Serializable::currentSection()
	{
	assert(!path.empty());

	return path.top();
	}

	const char *CheckpointIn::baseFilename = "m5.cpt";

	string CheckpointIn::currentDirectory;

	string
	CheckpointIn::setDir(const string &name)
	{
	// use csprintf to insert curTick() into directory name if it
	// appears to have a format placeholder in it.
	currentDirectory = (name.find("%") != string::npos) ?
	csprintf(name, curTick()) : name;
	if (currentDirectory[currentDirectory.size() - 1] != '/')
	currentDirectory += "/";
	return currentDirectory;
	}

	string
	CheckpointIn::dir()
	{
	return currentDirectory;
	}


	CheckpointIn::CheckpointIn(const string &cpt_dir, SimObjectResolver &resolver)
	: db(new IniFile), objNameResolver(resolver), cptDir(setDir(cpt_dir))
	{
	string filename = cptDir + "/" + CheckpointIn::baseFilename;
	if (!db->load(filename)) {
	fatal("Can't load checkpoint file '%s'\n", filename);
	}
	}

	CheckpointIn::~CheckpointIn()
	{
	delete db;
	}

	bool
	CheckpointIn::entryExists(const string &section, const string &entry)
	{
	return db->entryExists(section, entry);
	}

	bool
	CheckpointIn::find(const string &section, const string &entry, string &value)
	{
	return db->find(section, entry, value);
	}


	bool
	CheckpointIn::findObj(const string &section, const string &entry,
	SimObject *&value)
	{
	string path;

	if (!db->find(section, entry, path))
	return false;

	value = objNameResolver.resolveSimObject(path);
	return true;
	}


	bool
	CheckpointIn::sectionExists(const string &section)
	{
	return db->sectionExists(section);
	}