Function set_function_parameters

external/include/backward/backward.hpp:2974–3069

Resolve the function return type and parameters

  // Resolve the function return type and parameters
  static void set_function_parameters(std::string &function_name,
                                      std::vector<std::string> &ns,
                                      dwarf_fileobject &fobj, Dwarf_Die die) {
    Dwarf_Debug dwarf = fobj.dwarf_handle.get();
    Dwarf_Error error = DW_DLE_NE;
    Dwarf_Die current_die = 0;
    std::string parameters;
    bool has_spec = true;
    // Check if we have a spec DIE. If we do we use it as it contains
    // more information, like parameter names.
    Dwarf_Die spec_die = get_spec_die(fobj, die);
    if (!spec_die) {
      has_spec = false;
      spec_die = die;
    }

    std::vector<std::string>::const_iterator it = ns.begin();
    std::string ns_name;
    for (it = ns.begin(); it < ns.end(); ++it) {
      ns_name.append(*it).append("::");
    }

    if (!ns_name.empty()) {
      function_name.insert(0, ns_name);
    }

    // See if we have a function return type. It can be either on the
    // current die or in its spec one (usually true for inlined functions)
    std::string return_type =
        get_referenced_die_name(dwarf, die, DW_AT_type, true);
    if (return_type.empty()) {
      return_type = get_referenced_die_name(dwarf, spec_die, DW_AT_type, true);
    }
    if (!return_type.empty()) {
      return_type.append(" ");
      function_name.insert(0, return_type);
    }

    if (dwarf_child(spec_die, &current_die, &error) == DW_DLV_OK) {
      for (;;) {
        Dwarf_Die sibling_die = 0;

        Dwarf_Half tag_value;
        dwarf_tag(current_die, &tag_value, &error);

        if (tag_value == DW_TAG_formal_parameter) {
          // Ignore artificial (ie, compiler generated) parameters
          bool is_artificial = false;
          Dwarf_Attribute attr_mem;
          if (dwarf_attr(current_die, DW_AT_artificial, &attr_mem, &error) ==
              DW_DLV_OK) {
            Dwarf_Bool flag = 0;
            if (dwarf_formflag(attr_mem, &flag, &error) == DW_DLV_OK) {
              is_artificial = flag != 0;
            }
            dwarf_dealloc(dwarf, attr_mem, DW_DLA_ATTR);
          }