C++ DECL_CONTEXT函數代碼示例

tree
build_capture_proxy (tree member)
{
  tree var, object, fn, closure, name, lam, type;

  if (PACK_EXPANSION_P (member))
    member = PACK_EXPANSION_PATTERN (member);

  closure = DECL_CONTEXT (member);
  fn = lambda_function (closure);
  lam = CLASSTYPE_LAMBDA_EXPR (closure);

  /* The proxy variable forwards to the capture field.  */
  object = build_fold_indirect_ref (DECL_ARGUMENTS (fn));
  object = finish_non_static_data_member (member, object, NULL_TREE);
  if (REFERENCE_REF_P (object))
    object = TREE_OPERAND (object, 0);

  /* Remove the __ inserted by add_capture.  */
  if (DECL_NORMAL_CAPTURE_P (member))
    name = get_identifier (IDENTIFIER_POINTER (DECL_NAME (member)) + 2);
  else
    name = DECL_NAME (member);

  type = lambda_proxy_type (object);

  if (DECL_VLA_CAPTURE_P (member))
    {
      /* Rebuild the VLA type from the pointer and maxindex.  */
      tree field = next_initializable_field (TYPE_FIELDS (type));
      tree ptr = build_simple_component_ref (object, field);
      field = next_initializable_field (DECL_CHAIN (field));
      tree max = build_simple_component_ref (object, field);
      type = build_cplus_array_type (TREE_TYPE (TREE_TYPE (ptr)),
				     build_index_type (max));
      type = build_reference_type (type);
      REFERENCE_VLA_OK (type) = true;
      object = convert (type, ptr);
    }

  var = build_decl (input_location, VAR_DECL, name, type);
  SET_DECL_VALUE_EXPR (var, object);
  DECL_HAS_VALUE_EXPR_P (var) = 1;
  DECL_ARTIFICIAL (var) = 1;
  TREE_USED (var) = 1;
  DECL_CONTEXT (var) = fn;

  if (name == this_identifier)
    {
      gcc_assert (LAMBDA_EXPR_THIS_CAPTURE (lam) == member);
      LAMBDA_EXPR_THIS_CAPTURE (lam) = var;
    }

  if (fn == current_function_decl)
    insert_capture_proxy (var);
  else
    vec_safe_push (LAMBDA_EXPR_PENDING_PROXIES (lam), var);

  return var;
}

static tree
vxworks_emutls_var_fields (tree type, tree *name)
{
  tree field, next_field;
  
  *name = get_identifier ("__tls_var");
  
  field = build_decl (BUILTINS_LOCATION, FIELD_DECL,
		      get_identifier ("size"), unsigned_type_node);
  DECL_CONTEXT (field) = type;
  next_field = field;

  field = build_decl (BUILTINS_LOCATION, FIELD_DECL,
		      get_identifier ("module_id"), unsigned_type_node);
  DECL_CONTEXT (field) = type;
  DECL_CHAIN (field) = next_field;
  next_field = field;

  field = build_decl (BUILTINS_LOCATION, FIELD_DECL,
		      get_identifier ("offset"), unsigned_type_node);
  DECL_CONTEXT (field) = type;
  DECL_CHAIN (field) = next_field;

  return field;
}

tree
pushdecl (tree decl)
{
  if (global_bindings_p ())
    DECL_CONTEXT (decl) = current_translation_unit;
  else
    {
      /* External objects aren't nested.  For debug info insert a copy
         of the decl into the binding level.  */
      if (DECL_EXTERNAL (decl))
	{
	  tree orig = decl;
	  decl = copy_node (decl);
	  DECL_CONTEXT (orig) = NULL_TREE;
	}
      DECL_CONTEXT (decl) = current_function_decl;
    }

  /* Put the declaration on the list.  */
  DECL_CHAIN (decl) = current_binding_level->names;
  current_binding_level->names = decl;

  /* For the declaration of a type, set its name if it is not already set.  */

  if (TREE_CODE (decl) == TYPE_DECL && TYPE_NAME (TREE_TYPE (decl)) == 0)
    {
      if (DECL_SOURCE_LINE (decl) == 0)
	TYPE_NAME (TREE_TYPE (decl)) = decl;
      else
	TYPE_NAME (TREE_TYPE (decl)) = DECL_NAME (decl);
    }

  return decl;
}

tree
cplus_expand_constant (tree cst)
{
  switch (TREE_CODE (cst))
    {
    case PTRMEM_CST:
      {
	tree type = TREE_TYPE (cst);
	tree member;

	/* Find the member.  */
	member = PTRMEM_CST_MEMBER (cst);

	/* We can't lower this until the class is complete.  */
	if (!COMPLETE_TYPE_P (DECL_CONTEXT (member)))
	  return cst;

	if (TREE_CODE (member) == FIELD_DECL)
	  {
	    /* Find the offset for the field.  */
	    cst = byte_position (member);
	    while (!same_type_p (DECL_CONTEXT (member),
				 TYPE_PTRMEM_CLASS_TYPE (type)))
	      {
		/* The MEMBER must have been nestled within an
		   anonymous aggregate contained in TYPE.  Find the
		   anonymous aggregate.  */
		member = lookup_anon_field (TYPE_PTRMEM_CLASS_TYPE (type),
					    DECL_CONTEXT (member));
		cst = size_binop (PLUS_EXPR, cst, byte_position (member));
	      }
	    cst = fold (build_nop (type, cst));
	  }
	else
	  {
	    tree delta;
	    tree pfn;

	    expand_ptrmemfunc_cst (cst, &delta, &pfn);
	    cst = build_ptrmemfunc1 (type, delta, pfn);
	  }
      }
      break;

    case CONSTRUCTOR:
      {
	constructor_elt *elt;
	unsigned HOST_WIDE_INT idx;
	FOR_EACH_VEC_SAFE_ELT (CONSTRUCTOR_ELTS (cst), idx, elt)
	  elt->value = cplus_expand_constant (elt->value);
      }

    default:
      /* There's nothing to do.  */
      break;
    }

  return cst;
}

static tree
associated_type (tree decl)
{
  /* APPLE LOCAL begin mainline 2005-10-12 */
  return  (DECL_CONTEXT (decl) && TYPE_P (DECL_CONTEXT (decl)))
            ?  DECL_CONTEXT (decl) : NULL_TREE;
  /* APPLE LOCAL end mainline 2005-10-12 */
}

void
java_mangle_decl (tree decl)
{
  /* A copy of the check from the beginning of lhd_set_decl_assembler_name.  */

  /* set_decl_assembler_name may be called on TYPE_DECL to record ODR
     name for C++ types.  By default types have no ODR names.  */
  if (TREE_CODE (decl) == TYPE_DECL)
    return;

  /* The language-independent code should never use the
     DECL_ASSEMBLER_NAME for lots of DECLs.  Only FUNCTION_DECLs and
     VAR_DECLs for variables with static storage duration need a real
     DECL_ASSEMBLER_NAME.  */
  gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
	      || (TREE_CODE (decl) == VAR_DECL
		  && (TREE_STATIC (decl)
		      || DECL_EXTERNAL (decl)
		      || TREE_PUBLIC (decl))));

  /* Mangling only applies to class members.  */
  if (DECL_CONTEXT (decl) && TYPE_P (DECL_CONTEXT (decl)))
    {
      init_mangling ();
      switch (TREE_CODE (decl))
	{
	case VAR_DECL:
	  if (DECL_LANG_SPECIFIC (decl))
	    {
	      if (DECL_CLASS_FIELD_P (decl))
		{
		  mangle_class_field (decl);
		  break;
		}
	      else if (DECL_VTABLE_P (decl))
		{
		  mangle_vtable (DECL_CONTEXT (decl));
		  break;
		}
	    }
	  mangle_field_decl (decl);
	  break;

	case FUNCTION_DECL:
	  if (DECL_LANG_SPECIFIC (decl) && DECL_LOCAL_CNI_METHOD_P (decl))
	    mangle_local_cni_method_decl (decl);
	  else
	    mangle_method_decl (decl);
	  break;

	default:
	  gcc_unreachable ();
	}
      SET_DECL_ASSEMBLER_NAME (decl, finish_mangling ());
    }
  else
    lhd_set_decl_assembler_name (decl);
}

void
java_mangle_decl (tree decl)
{
  /* A copy of the check from the beginning of lhd_set_decl_assembler_name.
     Only FUNCTION_DECLs and VAR_DECLs for variables with static storage
     duration need a real DECL_ASSEMBLER_NAME.  */
  gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
	      || (TREE_CODE (decl) == VAR_DECL
		  && (TREE_STATIC (decl)
		      || DECL_EXTERNAL (decl)
		      || TREE_PUBLIC (decl))));
  
  /* Mangling only applies to class members.  */
  if (DECL_CONTEXT (decl) && TYPE_P (DECL_CONTEXT (decl)))
    {
      init_mangling ();
      switch (TREE_CODE (decl))
	{
	case VAR_DECL:
	  if (DECL_LANG_SPECIFIC (decl))
	    {
	      if (DECL_CLASS_FIELD_P (decl))
		{
		  mangle_class_field (decl);
		  break;
		}
	      else if (DECL_VTABLE_P (decl))
		{
		  mangle_vtable (DECL_CONTEXT (decl));
		  break;
		}
	    }
	  mangle_field_decl (decl);
	  break;

	case FUNCTION_DECL:
	  if (DECL_LANG_SPECIFIC (decl) && DECL_LOCAL_CNI_METHOD_P (decl))
	    mangle_local_cni_method_decl (decl);
	  else
	    mangle_method_decl (decl);
	  break;

	default:
	  gcc_unreachable ();
	}
      SET_DECL_ASSEMBLER_NAME (decl, finish_mangling ());
    }
  else
    lhd_set_decl_assembler_name (decl);
}

static void
pp_cxx_original_namespace_definition (cxx_pretty_printer *pp, tree t)
{
  pp_cxx_identifier (pp, "namespace");
  if (DECL_CONTEXT (t))
    pp_cxx_nested_name_specifier (pp, DECL_CONTEXT (t));
  if (DECL_NAME (t))
    pp_cxx_unqualified_id (pp, t);
  pp_cxx_whitespace (pp);
  pp_cxx_left_brace (pp);
  /* We do not print the namespace-body.  */
  pp_cxx_whitespace (pp);
  pp_cxx_right_brace (pp);
}

static void
pp_cxx_qualified_id (cxx_pretty_printer *pp, tree t)
{
  switch (TREE_CODE (t))
    {
      /* A pointer-to-member is always qualified.  */
    case PTRMEM_CST:
      pp_cxx_nested_name_specifier (pp, PTRMEM_CST_CLASS (t));
      pp_cxx_unqualified_id (pp, PTRMEM_CST_MEMBER (t));
      break;

      /* In Standard C++, functions cannot possibly be used as
	 nested-name-specifiers.  However, there are situations where
	 is "makes sense" to output the surrounding function name for the
	 purpose of emphasizing on the scope kind.  Just printing the
	 function name might not be sufficient as it may be overloaded; so,
	 we decorate the function with its signature too.
	 FIXME:  This is probably the wrong pretty-printing for conversion
	 functions and some function templates.  */
    case OVERLOAD:
      t = OVL_CURRENT (t);
    case FUNCTION_DECL:
      if (DECL_FUNCTION_MEMBER_P (t))
	pp_cxx_nested_name_specifier (pp, DECL_CONTEXT (t));
      pp_cxx_unqualified_id
	(pp, DECL_CONSTRUCTOR_P (t) ? DECL_CONTEXT (t) : t);
      pp_cxx_parameter_declaration_clause (pp, TREE_TYPE (t));
      break;

    case OFFSET_REF:
    case SCOPE_REF:
      pp_cxx_nested_name_specifier (pp, TREE_OPERAND (t, 0));
      pp_cxx_unqualified_id (pp, TREE_OPERAND (t, 1));
      break;

    default:
      {
	tree scope = TYPE_P (t) ? TYPE_CONTEXT (t) : DECL_CONTEXT (t);
	if (scope != pp->enclosing_scope)
	  {
	    pp_cxx_nested_name_specifier (pp, scope);
	    pp_cxx_template_keyword_if_needed (pp, scope, t);
	  }
	pp_cxx_unqualified_id (pp, t);
      }
      break;
    }
}

void
gfc_generate_module_code (gfc_namespace * ns)
{
  gfc_namespace *n;
  struct module_htab_entry *entry;

  gcc_assert (ns->proc_name->backend_decl == NULL);
  ns->proc_name->backend_decl
    = build_decl (ns->proc_name->declared_at.lb->location,
		  NAMESPACE_DECL, get_identifier (ns->proc_name->name),
		  void_type_node);
  entry = gfc_find_module (ns->proc_name->name);
  if (entry->namespace_decl)
    /* Buggy sourcecode, using a module before defining it?  */
    htab_empty (entry->decls);
  entry->namespace_decl = ns->proc_name->backend_decl;

  gfc_generate_module_vars (ns);

  /* We need to generate all module function prototypes first, to allow
     sibling calls.  */
  for (n = ns->contained; n; n = n->sibling)
    {
      gfc_entry_list *el;

      if (!n->proc_name)
        continue;

      gfc_create_function_decl (n);
      gcc_assert (DECL_CONTEXT (n->proc_name->backend_decl) == NULL_TREE);
      DECL_CONTEXT (n->proc_name->backend_decl) = ns->proc_name->backend_decl;
      gfc_module_add_decl (entry, n->proc_name->backend_decl);
      for (el = ns->entries; el; el = el->next)
	{
	  gcc_assert (DECL_CONTEXT (el->sym->backend_decl) == NULL_TREE);
	  DECL_CONTEXT (el->sym->backend_decl) = ns->proc_name->backend_decl;
	  gfc_module_add_decl (entry, el->sym->backend_decl);
	}
    }

  for (n = ns->contained; n; n = n->sibling)
    {
      if (!n->proc_name)
        continue;

      gfc_generate_function_code (n);
    }
}

tree
make_alias_for (tree function, tree newid)
{
    tree alias = build_decl (FUNCTION_DECL, newid, TREE_TYPE (function));
    DECL_LANG_SPECIFIC (alias) = DECL_LANG_SPECIFIC (function);
    cxx_dup_lang_specific_decl (alias);
    DECL_CONTEXT (alias) = NULL;
    TREE_READONLY (alias) = TREE_READONLY (function);
    TREE_THIS_VOLATILE (alias) = TREE_THIS_VOLATILE (function);
    TREE_PUBLIC (alias) = 0;
    DECL_INTERFACE_KNOWN (alias) = 1;
    DECL_NOT_REALLY_EXTERN (alias) = 1;
    DECL_THIS_STATIC (alias) = 1;
    DECL_SAVED_FUNCTION_DATA (alias) = NULL;
    DECL_DESTRUCTOR_P (alias) = 0;
    DECL_CONSTRUCTOR_P (alias) = 0;
    DECL_CLONED_FUNCTION (alias) = NULL_TREE;
    DECL_EXTERNAL (alias) = 0;
    DECL_ARTIFICIAL (alias) = 1;
    DECL_NO_STATIC_CHAIN (alias) = 1;
    DECL_PENDING_INLINE_P (alias) = 0;
    DECL_INLINE (alias) = 0;
    DECL_DECLARED_INLINE_P (alias) = 0;
    DECL_DEFERRED_FN (alias) = 0;
    DECL_USE_TEMPLATE (alias) = 0;
    DECL_TEMPLATE_INSTANTIATED (alias) = 0;
    DECL_TEMPLATE_INFO (alias) = NULL;
    DECL_INITIAL (alias) = error_mark_node;
    TREE_ADDRESSABLE (alias) = 1;
    TREE_USED (alias) = 1;
    SET_DECL_ASSEMBLER_NAME (alias, DECL_NAME (alias));
    TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias)) = 1;
    return alias;
}

static tree
make_fname_decl ()
{
    const char *name = lang_hooks.decl_printable_name (current_function_decl, 0);
    tree decl, type, init;
    size_t length = strlen (name);

    type = build_array_type (build_type_variant (char_type_node, true, false),
                             build_index_type (size_int (length)));

    decl = build_decl (UNKNOWN_LOCATION, VAR_DECL,
                       get_identifier ("__function_name__"), type);

    TREE_STATIC (decl) = 1;
    TREE_READONLY (decl) = 1;
    DECL_ARTIFICIAL (decl) = 1;

    init = build_string (length + 1, name);
    TREE_TYPE (init) = type;
    TREE_READONLY (init) = 1;
    DECL_READ_P (decl) = 1;
    DECL_INITIAL (decl) = init;

    TREE_USED (decl) = 1;
    TREE_ADDRESSABLE (decl) = 1;
    DECL_CONTEXT (decl) = current_function_decl;

    return decl;
}

static tree
ubsan_type_descriptor_type (void)
{
  static const char *field_names[3]
    = { "__typekind", "__typeinfo", "__typename" };
  tree fields[3], ret;
  tree itype = build_range_type (sizetype, size_zero_node, NULL_TREE);
  tree flex_arr_type = build_array_type (char_type_node, itype);

  ret = make_node (RECORD_TYPE);
  for (int i = 0; i < 3; i++)
    {
      fields[i] = build_decl (UNKNOWN_LOCATION, FIELD_DECL,
			      get_identifier (field_names[i]),
			      (i == 2) ? flex_arr_type
			      : short_unsigned_type_node);
      DECL_CONTEXT (fields[i]) = ret;
      if (i)
	DECL_CHAIN (fields[i - 1]) = fields[i];
    }
  TYPE_FIELDS (ret) = fields[0];
  TYPE_NAME (ret) = get_identifier ("__ubsan_type_descriptor");
  layout_type (ret);
  return ret;
}

static void
pp_cxx_namespace_alias_definition (cxx_pretty_printer *pp, tree t)
{
  pp_cxx_identifier (pp, "namespace");
  if (DECL_CONTEXT (t))
    pp_cxx_nested_name_specifier (pp, DECL_CONTEXT (t));
  pp_cxx_unqualified_id (pp, t);
  pp_cxx_whitespace (pp);
  pp_equal (pp);
  pp_cxx_whitespace (pp);
  if (DECL_CONTEXT (DECL_NAMESPACE_ALIAS (t)))
    pp_cxx_nested_name_specifier (pp, 
				  DECL_CONTEXT (DECL_NAMESPACE_ALIAS (t)));
  pp_cxx_qualified_id (pp, DECL_NAMESPACE_ALIAS (t));
  pp_cxx_semicolon (pp);
}

static void
lto_input_ts_decl_minimal_tree_pointers (struct lto_input_block *ib,
					 struct data_in *data_in, tree expr)
{
  DECL_NAME (expr) = stream_read_tree (ib, data_in);
  DECL_CONTEXT (expr) = stream_read_tree (ib, data_in);
}