//@HEADER
// ************************************************************************
//
//                        Kokkos v. 4.0
//       Copyright (2022) National Technology & Engineering
//               Solutions of Sandia, LLC (NTESS).
//
// Under the terms of Contract DE-NA0003525 with NTESS,
// the U.S. Government retains certain rights in this software.
//
// Part of Kokkos, under the Apache License v2.0 with LLVM Exceptions.
// See https://kokkos.org/LICENSE for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//@HEADER

#ifndef KOKKOS_IMPL_PUBLIC_INCLUDE
#define KOKKOS_IMPL_PUBLIC_INCLUDE
#endif

#ifndef KOKKOS_TOOLS_INDEPENDENT_BUILD
#include <Kokkos_Macros.hpp>
#include <Kokkos_Tuners.hpp>
#endif

#include <impl/Kokkos_Profiling.hpp>
#include <impl/Kokkos_Profiling_Interface.hpp>
#include <impl/Kokkos_Command_Line_Parsing.hpp>

#if defined(KOKKOS_ENABLE_LIBDL) || defined(KOKKOS_TOOLS_INDEPENDENT_BUILD)
#include <dlfcn.h>
#define KOKKOS_TOOLS_ENABLE_LIBDL
#endif

#include <algorithm>
#include <array>
#include <cstring>
#include <iostream>
#include <memory>
#include <stack>
#include <unordered_map>
#include <unordered_set>
#include <vector>
#include <sstream>
#include <iostream>

namespace {
void warn_cmd_line_arg_ignored_when_kokkos_tools_disabled(char const* arg) {
#ifndef KOKKOS_TOOLS_ENABLE_LIBDL
  if (Kokkos::show_warnings()) {
    std::cerr << "Warning: command line argument '" << arg
              << "' ignored because kokkos-tools is disabled."
              << " Raised by Kokkos::initialize()." << std::endl;
  }
#else
  (void)arg;
#endif
}
void warn_env_var_ignored_when_kokkos_tools_disabled(char const* env_var,
                                                     char const* val) {
#ifndef KOKKOS_TOOLS_ENABLE_LIBDL
  if (Kokkos::show_warnings()) {
    std::cerr << "Warning: environment variable '" << env_var << "=" << val
              << "' ignored because kokkos-tools is disabled."
              << " Raised by Kokkos::initialize()." << std::endl;
  }
#else
  (void)env_var;
  (void)val;
#endif
}
}  // namespace

namespace Kokkos {

namespace Tools {

const std::string InitArguments::unset_string_option = {
    "kokkos_tools_impl_unset_option"};

InitArguments tool_arguments;

namespace Impl {
void parse_command_line_arguments(int& argc, char* argv[],
                                  InitArguments& arguments) {
  int iarg = 0;
  using Kokkos::Impl::check_arg;
  using Kokkos::Impl::check_arg_str;

  auto& libs = arguments.lib;
  auto& args = arguments.args;
  auto& help = arguments.help;
  while (iarg < argc) {
    bool remove_flag = false;
    if (check_arg_str(argv[iarg], "--kokkos-tools-libs", libs) ||
        check_arg_str(argv[iarg], "--kokkos-tools-library", libs)) {
      if (check_arg(argv[iarg], "--kokkos-tools-library")) {
        using Kokkos::Impl::warn_deprecated_command_line_argument;
        warn_deprecated_command_line_argument("--kokkos-tools-library",
                                              "--kokkos-tools-libs");
      }
      warn_cmd_line_arg_ignored_when_kokkos_tools_disabled(argv[iarg]);
      remove_flag = true;
    } else if (check_arg_str(argv[iarg], "--kokkos-tools-args", args)) {
      warn_cmd_line_arg_ignored_when_kokkos_tools_disabled(argv[iarg]);
      remove_flag = true;
      // strip any leading and/or trailing quotes if they were retained in the
      // string because this will very likely cause parsing issues for tools.
      // If the quotes are retained (via bypassing the shell):
      //    <EXE> --kokkos-tools-args="-c my example"
      // would be tokenized as:
      //    "<EXE>" "\"-c" "my" "example\""
      // instead of:
      //    "<EXE>" "-c" "my" "example"
      if (!args.empty()) {
        if (args.front() == '"') args = args.substr(1);
        if (args.back() == '"') args = args.substr(0, args.length() - 1);
      }
      // add the name of the executable to the beginning
      if (argc > 0) args = std::string(argv[0]) + " " + args;
    } else if (check_arg(argv[iarg], "--kokkos-tools-help")) {
      help = InitArguments::PossiblyUnsetOption::on;
      warn_cmd_line_arg_ignored_when_kokkos_tools_disabled(argv[iarg]);
      remove_flag = true;
    } else if (std::regex_match(argv[iarg], std::regex("-?-kokkos-tool.*",
                                                       std::regex::egrep))) {
      std::cerr << "Warning: command line argument '" << argv[iarg]
                << "' is not recognized."
                << " Raised by Kokkos::initialize()." << std::endl;
    }
    if (remove_flag) {
      // Shift the remainder of the argv list by one.  Note that argv has
      // (argc + 1) arguments, the last one always being nullptr.  The following
      // loop moves the trailing nullptr element as well
      for (int k = iarg; k < argc; ++k) {
        argv[k] = argv[k + 1];
      }
      argc--;
    } else {
      iarg++;
    }
    if ((args == Kokkos::Tools::InitArguments::unset_string_option) && argc > 0)
      args = argv[0];
  }
}
Kokkos::Tools::Impl::InitializationStatus parse_environment_variables(
    InitArguments& arguments) {
  auto& libs               = arguments.lib;
  auto& args               = arguments.args;
  auto env_profile_library = std::getenv("KOKKOS_PROFILE_LIBRARY");
  if (env_profile_library != nullptr) {
    using Kokkos::Impl::warn_deprecated_environment_variable;
    warn_deprecated_environment_variable("KOKKOS_PROFILE_LIBRARY",
                                         "KOKKOS_TOOLS_LIBS");
    warn_env_var_ignored_when_kokkos_tools_disabled("KOKKOS_PROFILE_LIBRARY",
                                                    env_profile_library);
    libs = env_profile_library;
  }
  auto env_tools_libs = std::getenv("KOKKOS_TOOLS_LIBS");
  if (env_tools_libs != nullptr) {
    warn_env_var_ignored_when_kokkos_tools_disabled("KOKKOS_TOOLS_LIBS",
                                                    env_tools_libs);
    if (env_profile_library != nullptr && libs != env_tools_libs) {
      std::stringstream ss;
      ss << "Error: environment variables 'KOKKOS_PROFILE_LIBRARY="
         << env_profile_library << "' and 'KOKKOS_TOOLS_LIBS=" << env_tools_libs
         << "' are both set and do not match."
         << " Raised by Kokkos::initialize().\n";
      Kokkos::abort(ss.str().c_str());
    }
    libs = env_tools_libs;
  }
  auto env_tools_args = std::getenv("KOKKOS_TOOLS_ARGS");
  if (env_tools_args != nullptr) {
    warn_env_var_ignored_when_kokkos_tools_disabled("KOKKOS_TOOLS_ARGS",
                                                    env_tools_args);
    args = env_tools_args;
  }
  return {
      Kokkos::Tools::Impl::InitializationStatus::InitializationResult::success,
      ""};
}
InitializationStatus initialize_tools_subsystem(
    const Kokkos::Tools::InitArguments& args) {
#ifdef KOKKOS_TOOLS_ENABLE_LIBDL
  Kokkos::Profiling::initialize(args.lib);
  auto final_args =
      (args.args != Kokkos::Tools::InitArguments::unset_string_option)
          ? args.args
          : "";

  if (args.help) {
    if (!Kokkos::Tools::printHelp(final_args)) {
      std::cerr << "Tool has not provided a help message" << std::endl;
    }
    return {InitializationStatus::InitializationResult::help_request, ""};
  }
  Kokkos::Tools::parseArgs(final_args);
#else
  (void)args;
#endif
  return {InitializationStatus::InitializationResult::success, ""};
}

}  // namespace Impl
void initialize(const InitArguments& arguments) {
  Impl::initialize_tools_subsystem(arguments);
}
void initialize(int argc, char* argv[]) {
  InitArguments arguments;
  Impl::parse_environment_variables(arguments);
  Impl::parse_command_line_arguments(argc, argv, arguments);
  initialize(arguments);
}

namespace Experimental {

namespace Impl {
void tool_invoked_fence(const uint32_t /* devID */) {
  /**
   * Currently the function ignores the device ID,
   * Eventually we want to support fencing only
   * a given stream/resource
   */
#ifndef KOKKOS_TOOLS_INDEPENDENT_BUILD
  Kokkos::fence(
      "Kokkos::Tools::Experimental::Impl::tool_invoked_fence: Tool Requested "
      "Fence");
#endif
}
}  // namespace Impl

#ifdef KOKKOS_ENABLE_TUNING
static size_t kernel_name_context_variable_id;
static size_t kernel_type_context_variable_id;
static std::unordered_map<size_t, std::unordered_set<size_t>>
    features_per_context;
static std::unordered_set<size_t> active_features;
static std::unordered_map<size_t, VariableValue> feature_values;
static std::unordered_map<size_t, VariableInfo> variable_metadata;
#endif
static EventSet current_callbacks;
static EventSet backup_callbacks;
static EventSet no_profiling;
static ToolSettings tool_requirements;
bool eventSetsEqual(const EventSet& l, const EventSet& r) {
  return l.init == r.init && l.finalize == r.finalize &&
         l.parse_args == r.parse_args && l.print_help == r.print_help &&
         l.begin_parallel_for == r.begin_parallel_for &&
         l.end_parallel_for == r.end_parallel_for &&
         l.begin_parallel_reduce == r.begin_parallel_reduce &&
         l.end_parallel_reduce == r.end_parallel_reduce &&
         l.begin_parallel_scan == r.begin_parallel_scan &&
         l.end_parallel_scan == r.end_parallel_scan &&
         l.push_region == r.push_region && l.pop_region == r.pop_region &&
         l.allocate_data == r.allocate_data &&
         l.deallocate_data == r.deallocate_data &&
         l.create_profile_section == r.create_profile_section &&
         l.start_profile_section == r.start_profile_section &&
         l.stop_profile_section == r.stop_profile_section &&
         l.destroy_profile_section == r.destroy_profile_section &&
         l.profile_event == r.profile_event &&
         l.begin_deep_copy == r.begin_deep_copy &&
         l.end_deep_copy == r.end_deep_copy && l.begin_fence == r.begin_fence &&
         l.end_fence == r.end_fence && l.sync_dual_view == r.sync_dual_view &&
         l.modify_dual_view == r.modify_dual_view &&
         l.declare_metadata == r.declare_metadata &&
         l.request_tool_settings == r.request_tool_settings &&
         l.provide_tool_programming_interface ==
             r.provide_tool_programming_interface &&
         l.declare_input_type == r.declare_input_type &&
         l.declare_output_type == r.declare_output_type &&
         l.end_tuning_context == r.end_tuning_context &&
         l.begin_tuning_context == r.begin_tuning_context &&
         l.request_output_values == r.request_output_values &&
         l.declare_optimization_goal == r.declare_optimization_goal;
}
enum class MayRequireGlobalFencing : bool { No, Yes };
template <typename Callback, typename... Args>
inline void invoke_kokkosp_callback(
    MayRequireGlobalFencing may_require_global_fencing,
    const Callback& callback, Args&&... args) {
  if (callback != nullptr) {
    // two clause if statement
    // may_require_global_fencing: "if this callback ever needs a fence", AND
    // if the tool requires global fencing (default true, but tools can
    // overwrite)
    if (may_require_global_fencing == MayRequireGlobalFencing::Yes &&
        (tool_requirements.requires_global_fencing)) {
#ifndef KOKKOS_TOOLS_INDEPENDENT_BUILD
      Kokkos::fence(
          "Kokkos::Tools::invoke_kokkosp_callback: Kokkos Profile Tool Fence");
#endif
    }
    (*callback)(std::forward<Args>(args)...);
  }
}
}  // namespace Experimental
bool profileLibraryLoaded() {
  return !Experimental::eventSetsEqual(Experimental::current_callbacks,
                                       Experimental::no_profiling);
}

void beginParallelFor(const std::string& kernelPrefix, const uint32_t devID,
                      uint64_t* kernelID) {
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::Yes,
      Experimental::current_callbacks.begin_parallel_for, kernelPrefix.c_str(),
      devID, kernelID);
#ifdef KOKKOS_ENABLE_TUNING
  if (Kokkos::tune_internals()) {
    auto context_id = Experimental::get_new_context_id();
    Experimental::begin_context(context_id);
    Experimental::VariableValue contextValues[] = {
        Experimental::make_variable_value(
            Experimental::kernel_name_context_variable_id, kernelPrefix),
        Experimental::make_variable_value(
            Experimental::kernel_type_context_variable_id, "parallel_for")};
    Experimental::set_input_values(context_id, 2, contextValues);
  }
#endif
}

void endParallelFor(const uint64_t kernelID) {
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::Yes,
      Experimental::current_callbacks.end_parallel_for, kernelID);
#ifdef KOKKOS_ENABLE_TUNING
  if (Kokkos::tune_internals()) {
    Experimental::end_context(Experimental::get_current_context_id());
  }
#endif
}

void beginParallelScan(const std::string& kernelPrefix, const uint32_t devID,
                       uint64_t* kernelID) {
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::Yes,
      Experimental::current_callbacks.begin_parallel_scan, kernelPrefix.c_str(),
      devID, kernelID);
#ifdef KOKKOS_ENABLE_TUNING
  if (Kokkos::tune_internals()) {
    auto context_id = Experimental::get_new_context_id();
    Experimental::begin_context(context_id);
    Experimental::VariableValue contextValues[] = {
        Experimental::make_variable_value(
            Experimental::kernel_name_context_variable_id, kernelPrefix),
        Experimental::make_variable_value(
            Experimental::kernel_type_context_variable_id, "parallel_for")};
    Experimental::set_input_values(context_id, 2, contextValues);
  }
#endif
}

void endParallelScan(const uint64_t kernelID) {
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::Yes,
      Experimental::current_callbacks.end_parallel_scan, kernelID);
#ifdef KOKKOS_ENABLE_TUNING
  if (Kokkos::tune_internals()) {
    Experimental::end_context(Experimental::get_current_context_id());
  }
#endif
}

void beginParallelReduce(const std::string& kernelPrefix, const uint32_t devID,
                         uint64_t* kernelID) {
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::Yes,
      Experimental::current_callbacks.begin_parallel_reduce,
      kernelPrefix.c_str(), devID, kernelID);
#ifdef KOKKOS_ENABLE_TUNING
  if (Kokkos::tune_internals()) {
    auto context_id = Experimental::get_new_context_id();
    Experimental::begin_context(context_id);
    Experimental::VariableValue contextValues[] = {
        Experimental::make_variable_value(
            Experimental::kernel_name_context_variable_id, kernelPrefix),
        Experimental::make_variable_value(
            Experimental::kernel_type_context_variable_id, "parallel_for")};
    Experimental::set_input_values(context_id, 2, contextValues);
  }
#endif
}

void endParallelReduce(const uint64_t kernelID) {
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::Yes,
      Experimental::current_callbacks.end_parallel_reduce, kernelID);
#ifdef KOKKOS_ENABLE_TUNING
  if (Kokkos::tune_internals()) {
    Experimental::end_context(Experimental::get_current_context_id());
  }
#endif
}

void pushRegion(const std::string& kName) {
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::Yes,
      Experimental::current_callbacks.push_region, kName.c_str());
}

void popRegion() {
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::Yes,
      Experimental::current_callbacks.pop_region);
}

void allocateData(const SpaceHandle space, const std::string label,
                  const void* ptr, const uint64_t size) {
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::No,
      Experimental::current_callbacks.allocate_data, space, label.c_str(), ptr,
      size);
}

void deallocateData(const SpaceHandle space, const std::string label,
                    const void* ptr, const uint64_t size) {
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::No,
      Experimental::current_callbacks.deallocate_data, space, label.c_str(),
      ptr, size);
}

void beginDeepCopy(const SpaceHandle dst_space, const std::string dst_label,
                   const void* dst_ptr, const SpaceHandle src_space,
                   const std::string src_label, const void* src_ptr,
                   const uint64_t size) {
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::No,
      Experimental::current_callbacks.begin_deep_copy, dst_space,
      dst_label.c_str(), dst_ptr, src_space, src_label.c_str(), src_ptr, size);
#ifdef KOKKOS_ENABLE_TUNING
  if (Experimental::current_callbacks.begin_deep_copy != nullptr) {
    if (Kokkos::tune_internals()) {
      auto context_id = Experimental::get_new_context_id();
      Experimental::begin_context(context_id);
      Experimental::VariableValue contextValues[] = {
          Experimental::make_variable_value(
              Experimental::kernel_name_context_variable_id,
              "deep_copy_kernel"),
          Experimental::make_variable_value(
              Experimental::kernel_type_context_variable_id, "deep_copy")};
      Experimental::set_input_values(context_id, 2, contextValues);
    }
  }
#endif
}

void endDeepCopy() {
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::No,
      Experimental::current_callbacks.end_deep_copy);
#ifdef KOKKOS_ENABLE_TUNING
  if (Experimental::current_callbacks.end_deep_copy != nullptr) {
    if (Kokkos::tune_internals()) {
      Experimental::end_context(Experimental::get_current_context_id());
    }
  }
#endif
}

void beginFence(const std::string name, const uint32_t deviceId,
                uint64_t* handle) {
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::No,
      Experimental::current_callbacks.begin_fence, name.c_str(), deviceId,
      handle);
}

void endFence(const uint64_t handle) {
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::No,
      Experimental::current_callbacks.end_fence, handle);
}

void createProfileSection(const std::string& sectionName, uint32_t* secID) {
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::No,
      Experimental::current_callbacks.create_profile_section,
      sectionName.c_str(), secID);
}

void startSection(const uint32_t secID) {
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::No,
      Experimental::current_callbacks.start_profile_section, secID);
}

void stopSection(const uint32_t secID) {
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::No,
      Experimental::current_callbacks.stop_profile_section, secID);
}

void destroyProfileSection(const uint32_t secID) {
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::No,
      Experimental::current_callbacks.destroy_profile_section, secID);
}

void markEvent(const std::string& eventName) {
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::No,
      Experimental::current_callbacks.profile_event, eventName.c_str());
}

bool printHelp(const std::string& args) {
  if (Experimental::current_callbacks.print_help == nullptr) {
    return false;
  }
  std::string arg0  = args.substr(0, args.find_first_of(' '));
  const char* carg0 = arg0.c_str();
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::No,
      Experimental::current_callbacks.print_help, const_cast<char*>(carg0));
  return true;
}

void parseArgs(int _argc, char** _argv) {
  if (Experimental::current_callbacks.parse_args != nullptr && _argc > 0) {
    Experimental::invoke_kokkosp_callback(
        Experimental::MayRequireGlobalFencing::No,
        Experimental::current_callbacks.parse_args, _argc, _argv);
  }
}

void parseArgs(const std::string& args) {
  if (Experimental::current_callbacks.parse_args == nullptr) {
    return;
  }
  using strvec_t = std::vector<std::string>;
  auto tokenize  = [](const std::string& line, const std::string& delimiters) {
    strvec_t _result{};
    std::size_t _bidx = 0;  // position that is the beginning of the new string
    std::size_t _didx = 0;  // position of the delimiter in the string
    while (_bidx < line.length() && _didx < line.length()) {
      // find the first character (starting at _didx) that is not a delimiter
      _bidx = line.find_first_not_of(delimiters, _didx);
      // if no more non-delimiter chars, done
      if (_bidx == std::string::npos) break;
      // starting at the position of the new string, find the next delimiter
      _didx = line.find_first_of(delimiters, _bidx);
      // starting at the position of the new string, get the characters
      // between this position and the next delimiter
      std::string _tmp = line.substr(_bidx, _didx - _bidx);
      // don't add empty strings
      if (!_tmp.empty()) _result.emplace_back(_tmp);
    }
    return _result;
  };
  auto vargs = tokenize(args, " \t");
  if (vargs.size() == 0) return;
  auto _argc          = static_cast<int>(vargs.size());
  char** _argv        = new char*[_argc + 1];
  _argv[vargs.size()] = nullptr;
  for (int i = 0; i < _argc; ++i) {
    auto& _str = vargs.at(i);
    _argv[i]   = new char[_str.length() + 1];
    std::memcpy(_argv[i], _str.c_str(), _str.length() * sizeof(char));
    _argv[i][_str.length()] = '\0';
  }
  parseArgs(_argc, _argv);
  for (int i = 0; i < _argc; ++i) {
    delete[] _argv[i];
  }
  delete[] _argv;
}

SpaceHandle make_space_handle(const char* space_name) {
  SpaceHandle handle;
  strncpy(handle.name, space_name, 63);
  return handle;
}

template <typename Callback>
void lookup_function(void* dlopen_handle, const std::string& basename,
                     Callback& callback) {
#ifdef KOKKOS_TOOLS_ENABLE_LIBDL
  // dlsym returns a pointer to an object, while we want to assign to
  // pointer to function A direct cast will give warnings hence, we have to
  // workaround the issue by casting pointer to pointers.
  void* p  = dlsym(dlopen_handle, basename.c_str());
  callback = *reinterpret_cast<Callback*>(&p);
#else
  (void)dlopen_handle;
  (void)basename;
  (void)callback;
#endif
}

void initialize(const std::string& profileLibrary) {
  // Make sure initialize calls happens only once
  static int is_initialized = 0;
  if (is_initialized) return;
  is_initialized = 1;

  auto invoke_init_callbacks = []() {
    Experimental::invoke_kokkosp_callback(
        Experimental::MayRequireGlobalFencing::No,
        Experimental::current_callbacks.init, 0,
        (uint64_t)KOKKOSP_INTERFACE_VERSION, (uint32_t)0, nullptr);

    Experimental::tool_requirements.requires_global_fencing = true;

    Experimental::invoke_kokkosp_callback(
        Experimental::MayRequireGlobalFencing::No,
        Experimental::current_callbacks.request_tool_settings, 1,
        &Experimental::tool_requirements);

    Experimental::ToolProgrammingInterface actions;
    actions.fence = &Experimental::Impl::tool_invoked_fence;

    Experimental::invoke_kokkosp_callback(
        Experimental::MayRequireGlobalFencing::No,
        Experimental::current_callbacks.provide_tool_programming_interface, 1,
        actions);
  };

#ifdef KOKKOS_TOOLS_ENABLE_LIBDL
  void* firstProfileLibrary = nullptr;

  if ((profileLibrary.empty()) ||
      (profileLibrary == InitArguments::unset_string_option)) {
    invoke_init_callbacks();
    return;
  }

  if (auto end_first_library = profileLibrary.find(';');
      end_first_library != 0) {
    auto profileLibraryName = profileLibrary.substr(0, end_first_library);
    firstProfileLibrary =
        dlopen(profileLibraryName.c_str(), RTLD_NOW | RTLD_GLOBAL);

    if (firstProfileLibrary == nullptr) {
      std::cerr << "Error: Unable to load KokkosP library: "
                << profileLibraryName << std::endl;
      std::cerr << "dlopen(" << profileLibraryName
                << ", RTLD_NOW | RTLD_GLOBAL) failed with " << dlerror()
                << '\n';
    } else {
      lookup_function(firstProfileLibrary, "kokkosp_begin_parallel_scan",
                      Experimental::current_callbacks.begin_parallel_scan);
      lookup_function(firstProfileLibrary, "kokkosp_begin_parallel_for",
                      Experimental::current_callbacks.begin_parallel_for);
      lookup_function(firstProfileLibrary, "kokkosp_begin_parallel_reduce",
                      Experimental::current_callbacks.begin_parallel_reduce);
      lookup_function(firstProfileLibrary, "kokkosp_end_parallel_scan",
                      Experimental::current_callbacks.end_parallel_scan);
      lookup_function(firstProfileLibrary, "kokkosp_end_parallel_for",
                      Experimental::current_callbacks.end_parallel_for);
      lookup_function(firstProfileLibrary, "kokkosp_end_parallel_reduce",
                      Experimental::current_callbacks.end_parallel_reduce);

      lookup_function(firstProfileLibrary, "kokkosp_init_library",
                      Experimental::current_callbacks.init);
      lookup_function(firstProfileLibrary, "kokkosp_finalize_library",
                      Experimental::current_callbacks.finalize);

      lookup_function(firstProfileLibrary, "kokkosp_push_profile_region",
                      Experimental::current_callbacks.push_region);
      lookup_function(firstProfileLibrary, "kokkosp_pop_profile_region",
                      Experimental::current_callbacks.pop_region);
      lookup_function(firstProfileLibrary, "kokkosp_allocate_data",
                      Experimental::current_callbacks.allocate_data);
      lookup_function(firstProfileLibrary, "kokkosp_deallocate_data",
                      Experimental::current_callbacks.deallocate_data);

      lookup_function(firstProfileLibrary, "kokkosp_begin_deep_copy",
                      Experimental::current_callbacks.begin_deep_copy);
      lookup_function(firstProfileLibrary, "kokkosp_end_deep_copy",
                      Experimental::current_callbacks.end_deep_copy);
      lookup_function(firstProfileLibrary, "kokkosp_begin_fence",
                      Experimental::current_callbacks.begin_fence);
      lookup_function(firstProfileLibrary, "kokkosp_end_fence",
                      Experimental::current_callbacks.end_fence);
      lookup_function(firstProfileLibrary, "kokkosp_dual_view_sync",
                      Experimental::current_callbacks.sync_dual_view);
      lookup_function(firstProfileLibrary, "kokkosp_dual_view_modify",
                      Experimental::current_callbacks.modify_dual_view);

      lookup_function(firstProfileLibrary, "kokkosp_declare_metadata",
                      Experimental::current_callbacks.declare_metadata);
      lookup_function(firstProfileLibrary, "kokkosp_create_profile_section",
                      Experimental::current_callbacks.create_profile_section);
      lookup_function(firstProfileLibrary, "kokkosp_start_profile_section",
                      Experimental::current_callbacks.start_profile_section);
      lookup_function(firstProfileLibrary, "kokkosp_stop_profile_section",
                      Experimental::current_callbacks.stop_profile_section);
      lookup_function(firstProfileLibrary, "kokkosp_destroy_profile_section",
                      Experimental::current_callbacks.destroy_profile_section);

      lookup_function(firstProfileLibrary, "kokkosp_profile_event",
                      Experimental::current_callbacks.profile_event);
#ifdef KOKKOS_ENABLE_TUNING
      lookup_function(firstProfileLibrary, "kokkosp_declare_output_type",
                      Experimental::current_callbacks.declare_output_type);

      lookup_function(firstProfileLibrary, "kokkosp_declare_input_type",
                      Experimental::current_callbacks.declare_input_type);
      lookup_function(firstProfileLibrary, "kokkosp_request_values",
                      Experimental::current_callbacks.request_output_values);
      lookup_function(firstProfileLibrary, "kokkosp_end_context",
                      Experimental::current_callbacks.end_tuning_context);
      lookup_function(firstProfileLibrary, "kokkosp_begin_context",
                      Experimental::current_callbacks.begin_tuning_context);
      lookup_function(
          firstProfileLibrary, "kokkosp_declare_optimization_goal",
          Experimental::current_callbacks.declare_optimization_goal);
#endif  // KOKKOS_ENABLE_TUNING

      lookup_function(firstProfileLibrary, "kokkosp_print_help",
                      Experimental::current_callbacks.print_help);
      lookup_function(firstProfileLibrary, "kokkosp_parse_args",
                      Experimental::current_callbacks.parse_args);
      lookup_function(
          firstProfileLibrary, "kokkosp_provide_tool_programming_interface",
          Experimental::current_callbacks.provide_tool_programming_interface);
      lookup_function(firstProfileLibrary, "kokkosp_request_tool_settings",
                      Experimental::current_callbacks.request_tool_settings);
    }
  }
#else
  (void)profileLibrary;
#endif  // KOKKOS_ENABLE_LIBDL

  invoke_init_callbacks();

#ifdef KOKKOS_ENABLE_TUNING
  Experimental::VariableInfo kernel_name;
  kernel_name.type = Experimental::ValueType::kokkos_value_string;
  kernel_name.category =
      Experimental::StatisticalCategory::kokkos_value_categorical;
  kernel_name.valueQuantity =
      Experimental::CandidateValueType::kokkos_value_unbounded;

  std::array<std::string, 4> candidate_values = {
      "parallel_for",
      "parallel_reduce",
      "parallel_scan",
      "parallel_copy",
  };

  Experimental::SetOrRange kernel_type_variable_candidates =
      Experimental::make_candidate_set(4, candidate_values.data());

  Experimental::kernel_name_context_variable_id =
      Experimental::declare_input_type("kokkos.kernel_name", kernel_name);

  Experimental::VariableInfo kernel_type;
  kernel_type.type = Experimental::ValueType::kokkos_value_string;
  kernel_type.category =
      Experimental::StatisticalCategory::kokkos_value_categorical;
  kernel_type.valueQuantity =
      Experimental::CandidateValueType::kokkos_value_set;
  kernel_type.candidates = kernel_type_variable_candidates;
  Experimental::kernel_type_context_variable_id =
      Experimental::declare_input_type("kokkos.kernel_type", kernel_type);

#endif

  Experimental::no_profiling.init     = nullptr;
  Experimental::no_profiling.finalize = nullptr;

  Experimental::no_profiling.begin_parallel_for    = nullptr;
  Experimental::no_profiling.begin_parallel_scan   = nullptr;
  Experimental::no_profiling.begin_parallel_reduce = nullptr;
  Experimental::no_profiling.end_parallel_scan     = nullptr;
  Experimental::no_profiling.end_parallel_for      = nullptr;
  Experimental::no_profiling.end_parallel_reduce   = nullptr;

  Experimental::no_profiling.push_region     = nullptr;
  Experimental::no_profiling.pop_region      = nullptr;
  Experimental::no_profiling.allocate_data   = nullptr;
  Experimental::no_profiling.deallocate_data = nullptr;

  Experimental::no_profiling.begin_deep_copy = nullptr;
  Experimental::no_profiling.end_deep_copy   = nullptr;

  Experimental::no_profiling.create_profile_section  = nullptr;
  Experimental::no_profiling.start_profile_section   = nullptr;
  Experimental::no_profiling.stop_profile_section    = nullptr;
  Experimental::no_profiling.destroy_profile_section = nullptr;

  Experimental::no_profiling.profile_event = nullptr;

  Experimental::no_profiling.declare_input_type    = nullptr;
  Experimental::no_profiling.declare_output_type   = nullptr;
  Experimental::no_profiling.request_output_values = nullptr;
  Experimental::no_profiling.end_tuning_context    = nullptr;
}

void finalize() {
  // Make sure finalize calls happens only once
  static int is_finalized = 0;
  if (is_finalized) return;
  is_finalized = 1;

  if (Experimental::current_callbacks.finalize != nullptr) {
    Experimental::invoke_kokkosp_callback(
        Experimental::MayRequireGlobalFencing::No,
        Experimental::current_callbacks.finalize);

    Experimental::pause_tools();
  }
#ifdef KOKKOS_ENABLE_TUNING
  // clean up string candidate set
  for (auto& metadata_pair : Experimental::variable_metadata) {
    auto metadata = metadata_pair.second;
    if ((metadata.type == Experimental::ValueType::kokkos_value_string) &&
        (metadata.valueQuantity ==
         Experimental::CandidateValueType::kokkos_value_set)) {
      auto candidate_set = metadata.candidates.set;
      delete[] candidate_set.values.string_value;
    }
  }
#endif
}

void syncDualView(const std::string& label, const void* const ptr,
                  bool to_device) {
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::No,
      Experimental::current_callbacks.sync_dual_view, label.c_str(), ptr,
      to_device);
}
void modifyDualView(const std::string& label, const void* const ptr,
                    bool on_device) {
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::No,
      Experimental::current_callbacks.modify_dual_view, label.c_str(), ptr,
      on_device);
}

void declareMetadata(const std::string& key, const std::string& value) {
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::No,
      Experimental::current_callbacks.declare_metadata, key.c_str(),
      value.c_str());
}

}  // namespace Tools

namespace Tools {
namespace Experimental {
void set_init_callback(initFunction callback) {
  current_callbacks.init = callback;
}
void set_finalize_callback(finalizeFunction callback) {
  current_callbacks.finalize = callback;
}
void set_parse_args_callback(parseArgsFunction callback) {
  current_callbacks.parse_args = callback;
}
void set_print_help_callback(printHelpFunction callback) {
  current_callbacks.print_help = callback;
}
void set_begin_parallel_for_callback(beginFunction callback) {
  current_callbacks.begin_parallel_for = callback;
}
void set_end_parallel_for_callback(endFunction callback) {
  current_callbacks.end_parallel_for = callback;
}
void set_begin_parallel_reduce_callback(beginFunction callback) {
  current_callbacks.begin_parallel_reduce = callback;
}
void set_end_parallel_reduce_callback(endFunction callback) {
  current_callbacks.end_parallel_reduce = callback;
}
void set_begin_parallel_scan_callback(beginFunction callback) {
  current_callbacks.begin_parallel_scan = callback;
}
void set_end_parallel_scan_callback(endFunction callback) {
  current_callbacks.end_parallel_scan = callback;
}
void set_push_region_callback(pushFunction callback) {
  current_callbacks.push_region = callback;
}
void set_pop_region_callback(popFunction callback) {
  current_callbacks.pop_region = callback;
}
void set_allocate_data_callback(allocateDataFunction callback) {
  current_callbacks.allocate_data = callback;
}
void set_deallocate_data_callback(deallocateDataFunction callback) {
  current_callbacks.deallocate_data = callback;
}
void set_create_profile_section_callback(
    createProfileSectionFunction callback) {
  current_callbacks.create_profile_section = callback;
}
void set_start_profile_section_callback(startProfileSectionFunction callback) {
  current_callbacks.start_profile_section = callback;
}
void set_stop_profile_section_callback(stopProfileSectionFunction callback) {
  current_callbacks.stop_profile_section = callback;
}
void set_destroy_profile_section_callback(
    destroyProfileSectionFunction callback) {
  current_callbacks.destroy_profile_section = callback;
}
void set_profile_event_callback(profileEventFunction callback) {
  current_callbacks.profile_event = callback;
}
void set_begin_deep_copy_callback(beginDeepCopyFunction callback) {
  current_callbacks.begin_deep_copy = callback;
}
void set_end_deep_copy_callback(endDeepCopyFunction callback) {
  current_callbacks.end_deep_copy = callback;
}
void set_begin_fence_callback(beginFenceFunction callback) {
  current_callbacks.begin_fence = callback;
}
void set_end_fence_callback(endFenceFunction callback) {
  current_callbacks.end_fence = callback;
}

void set_dual_view_sync_callback(dualViewSyncFunction callback) {
  current_callbacks.sync_dual_view = callback;
}
void set_dual_view_modify_callback(dualViewModifyFunction callback) {
  current_callbacks.modify_dual_view = callback;
}
void set_declare_metadata_callback(declareMetadataFunction callback) {
  current_callbacks.declare_metadata = callback;
}
void set_request_tool_settings_callback(requestToolSettingsFunction callback) {
  current_callbacks.request_tool_settings = callback;
}
void set_provide_tool_programming_interface_callback(
    provideToolProgrammingInterfaceFunction callback) {
  current_callbacks.provide_tool_programming_interface = callback;
}

void set_declare_output_type_callback(
    Experimental::outputTypeDeclarationFunction callback) {
  current_callbacks.declare_output_type = callback;
}
void set_declare_input_type_callback(
    Experimental::inputTypeDeclarationFunction callback) {
  current_callbacks.declare_input_type = callback;
}
void set_request_output_values_callback(
    Experimental::requestValueFunction callback) {
  current_callbacks.request_output_values = callback;
}
void set_end_context_callback(Experimental::contextEndFunction callback) {
  current_callbacks.end_tuning_context = callback;
}
void set_begin_context_callback(Experimental::contextBeginFunction callback) {
  current_callbacks.begin_tuning_context = callback;
}
void set_declare_optimization_goal_callback(
    Experimental::optimizationGoalDeclarationFunction callback) {
  current_callbacks.declare_optimization_goal = callback;
}

void pause_tools() {
  backup_callbacks  = current_callbacks;
  current_callbacks = no_profiling;
}

void resume_tools() { current_callbacks = backup_callbacks; }

Kokkos::Tools::Experimental::EventSet get_callbacks() {
  return current_callbacks;
}
void set_callbacks(Kokkos::Tools::Experimental::EventSet new_events) {
  current_callbacks = new_events;
}
}  // namespace Experimental
}  // namespace Tools

// Tuning

namespace Tools {
namespace Experimental {
static size_t& get_context_counter() {
  static size_t x;
  return x;
}
static size_t& get_variable_counter() {
  static size_t x;
  return ++x;
}

size_t get_new_context_id() { return ++get_context_counter(); }
size_t get_current_context_id() { return get_context_counter(); }
void decrement_current_context_id() { --get_context_counter(); }
size_t get_new_variable_id() { return get_variable_counter(); }

size_t declare_output_type(const std::string& variableName, VariableInfo info) {
  size_t variableId = get_new_variable_id();
#ifdef KOKKOS_ENABLE_TUNING
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::No,
      Experimental::current_callbacks.declare_output_type, variableName.c_str(),
      variableId, &info);
  variable_metadata[variableId] = info;
#else
  (void)variableName;
  (void)info;
#endif
  return variableId;
}

size_t declare_input_type(const std::string& variableName, VariableInfo info) {
  size_t variableId = get_new_variable_id();
#ifdef KOKKOS_ENABLE_TUNING
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::No,
      Experimental::current_callbacks.declare_input_type, variableName.c_str(),
      variableId, &info);
  variable_metadata[variableId] = info;
#else
  (void)variableName;
  (void)info;
#endif
  return variableId;
}

void set_input_values(size_t contextId, size_t count, VariableValue* values) {
#ifdef KOKKOS_ENABLE_TUNING
  if (features_per_context.find(contextId) == features_per_context.end()) {
    features_per_context[contextId] = std::unordered_set<size_t>();
  }
  for (size_t x = 0; x < count; ++x) {
    values[x].metadata = &variable_metadata[values[x].type_id];
    features_per_context[contextId].insert(values[x].type_id);
    active_features.insert(values[x].type_id);
    feature_values[values[x].type_id] = values[x];
  }
#else
  (void)contextId;
  (void)count;
  (void)values;
#endif
}
#include <iostream>
void request_output_values(size_t contextId, size_t count,
                           VariableValue* values) {
#ifdef KOKKOS_ENABLE_TUNING
  std::vector<size_t> context_ids;
  std::vector<VariableValue> context_values;
  for (auto id : active_features) {
    context_values.push_back(feature_values[id]);
  }
  if (Experimental::current_callbacks.request_output_values != nullptr) {
    for (size_t x = 0; x < count; ++x) {
      values[x].metadata = &variable_metadata[values[x].type_id];
    }
    Experimental::invoke_kokkosp_callback(
        Experimental::MayRequireGlobalFencing::No,
        Experimental::current_callbacks.request_output_values, contextId,
        context_values.size(), context_values.data(), count, values);
  }
#else
  (void)contextId;
  (void)count;
  (void)values;
#endif
}

#ifdef KOKKOS_ENABLE_TUNING
static std::unordered_map<size_t, size_t> optimization_goals;
#endif

void begin_context(size_t contextId) {
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::No,
      Experimental::current_callbacks.begin_tuning_context, contextId);
}
void end_context(size_t contextId) {
#ifdef KOKKOS_ENABLE_TUNING
  for (auto id : features_per_context[contextId]) {
    active_features.erase(id);
  }
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::No,
      Experimental::current_callbacks.end_tuning_context, contextId,
      feature_values[optimization_goals[contextId]]);
  optimization_goals.erase(contextId);
  decrement_current_context_id();
#else
  (void)contextId;
#endif
}

bool have_tuning_tool() {
#ifdef KOKKOS_ENABLE_TUNING
  return (Experimental::current_callbacks.request_output_values != nullptr);
#else
  return false;
#endif
}

VariableValue make_variable_value(size_t id, int64_t val) {
  VariableValue variable_value;
  variable_value.type_id         = id;
  variable_value.value.int_value = val;
  return variable_value;
}
VariableValue make_variable_value(size_t id, double val) {
  VariableValue variable_value;
  variable_value.type_id            = id;
  variable_value.value.double_value = val;
  return variable_value;
}
VariableValue make_variable_value(size_t id, const std::string& val) {
  VariableValue variable_value;
  variable_value.type_id = id;
  strncpy(variable_value.value.string_value, val.c_str(),
          KOKKOS_TOOLS_TUNING_STRING_LENGTH - 1);
  return variable_value;
}
SetOrRange make_candidate_set(size_t size, std::string* data) {
  SetOrRange value_set;
  value_set.set.values.string_value = new TuningString[size];
  for (size_t x = 0; x < size; ++x) {
    strncpy(value_set.set.values.string_value[x], data[x].c_str(),
            KOKKOS_TOOLS_TUNING_STRING_LENGTH - 1);
  }
  value_set.set.size = size;
  return value_set;
}
SetOrRange make_candidate_set(size_t size, int64_t* data) {
  SetOrRange value_set;
  value_set.set.size             = size;
  value_set.set.values.int_value = data;
  return value_set;
}
SetOrRange make_candidate_set(size_t size, double* data) {
  SetOrRange value_set;
  value_set.set.size                = size;
  value_set.set.values.double_value = data;
  return value_set;
}
SetOrRange make_candidate_range(double lower, double upper, double step,
                                bool openLower = false,
                                bool openUpper = false) {
  SetOrRange value_range;
  value_range.range.lower.double_value = lower;
  value_range.range.upper.double_value = upper;
  value_range.range.step.double_value  = step;
  value_range.range.openLower          = openLower;
  value_range.range.openUpper          = openUpper;
  return value_range;
}

SetOrRange make_candidate_range(int64_t lower, int64_t upper, int64_t step,
                                bool openLower = false,
                                bool openUpper = false) {
  SetOrRange value_range;
  value_range.range.lower.int_value = lower;
  value_range.range.upper.int_value = upper;
  value_range.range.step.int_value  = step;
  value_range.range.openLower       = openLower;
  value_range.range.openUpper       = openUpper;
  return value_range;
}

size_t get_new_context_id();
size_t get_current_context_id();
void decrement_current_context_id();
size_t get_new_variable_id();
void declare_optimization_goal(const size_t context,
                               const OptimizationGoal& goal) {
#ifdef KOKKOS_ENABLE_TUNING
  Experimental::invoke_kokkosp_callback(
      Experimental::MayRequireGlobalFencing::No,
      Experimental::current_callbacks.declare_optimization_goal, context, goal);
  optimization_goals[context] = goal.type_id;
#else
  (void)context;
  (void)goal;
#endif
}
}  // end namespace Experimental
}  // end namespace Tools

}  // end namespace Kokkos