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path: root/kernel/binding.cc

	Commit message (Collapse)	Author	Age	Files	Lines
*	Generate an RTLIL representation of bind constructs	Rupert Swarbrick	2021-08-13	1	-0/+29
	This code now takes the AST nodes of type AST_BIND and generates a representation in the RTLIL for them. This is a little tricky, because a binding of the form: bind baz foo_t foo_i (.arg (1 + bar)); means "make an instance of foo_t called foo_i, instantiate it inside baz and connect the port arg to the result of the expression 1+bar". Of course, 1+bar needs a cell for the addition. Where should that cell live? With this patch, the Binding structure that represents the construct is itself an AST::AstModule module. This lets us put the adder cell inside it. We'll pull the contents out and plonk them into 'baz' when we actually do the binding operation as part of the hierarchy pass. Of course, we don't want RTLIL::Binding to contain an AST::AstModule (since kernel code shouldn't depend on a frontend), so we define RTLIL::Binding as an abstract base class and put the AST-specific code into an AST::Binding subclass. This is analogous to the AST::AstModule class.

generated by cgit v1.2.3 (git 2.25.1) at 2025-04-18 21:39:42 +0000

--  Common operations on nodes.
--  Copyright (C) 2002, 2003, 2004, 2005 Tristan Gingold
--
--  GHDL is free software; you can redistribute it and/or modify it under
--  the terms of the GNU General Public License as published by the Free
--  Software Foundation; either version 2, or (at your option) any later
--  version.
--
--  GHDL is distributed in the hope that it will be useful, but WITHOUT ANY
--  WARRANTY; without even the implied warranty of MERCHANTABILITY or
--  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
--  for more details.
--
--  You should have received a copy of the GNU General Public License
--  along with GHDL; see the file COPYING.  If not, write to the Free
--  Software Foundation, 59 Temple Place - Suite 330, Boston, MA
--  02111-1307, USA.

with Flags; use Flags;
with Name_Table;
with Str_Table;
with Std_Names; use Std_Names;
with Vhdl.Std_Package;
with Vhdl.Errors; use Vhdl.Errors;
with PSL.Nodes;

package body Vhdl.Utils is
   function Is_Error (N : Iir) return Boolean is
   begin
      return Get_Kind (N) = Iir_Kind_Error;
   end Is_Error;

   function Is_Overflow_Literal (N : Iir) return Boolean is
   begin
      return Get_Kind (N) = Iir_Kind_Overflow_Literal;
   end Is_Overflow_Literal;

   function List_To_Flist (L : Iir_List) return Iir_Flist
   is
      Len : constant Natural := Get_Nbr_Elements (L);
      It : List_Iterator;
      Temp_L : Iir_List;
      Res : Iir_Flist;
   begin
      Res := Create_Iir_Flist (Len);
      It := List_Iterate (L);
      for I in 0 .. Len - 1 loop
         pragma Assert (Is_Valid (It));
         Set_Nth_Element (Res, I, Get_Element (It));
         Next (It);
      end loop;
      pragma Assert (not Is_Valid (It));

      Temp_L := L;
      Destroy_Iir_List (Temp_L);

      return Res;
   end List_To_Flist;

   function Truncate_Flist (L : Iir_Flist; Len : Natural) return Iir_Flist
   is
      Res : Iir_Flist;
      Temp_L : Iir_Flist;
   begin
      Res := Create_Iir_Flist (Len);
      for I in 0 .. Len - 1 loop
         Set_Nth_Element (Res, I, Get_Nth_Element (L, I));
      end loop;
      Temp_L := L;
      Destroy_Iir_Flist (Temp_L);
      return Res;
   end Truncate_Flist;

   function Get_Operator_Name (Op : Iir) return Name_Id is
   begin
      case Get_Kind (Op) is
         when Iir_Kind_And_Operator
           | Iir_Kind_Reduction_And_Operator =>
            return Name_And;
         when Iir_Kind_Or_Operator
           | Iir_Kind_Reduction_Or_Operator =>
            return Name_Or;
         when Iir_Kind_Nand_Operator
           | Iir_Kind_Reduction_Nand_Operator =>
            return Name_Nand;
         when Iir_Kind_Nor_Operator
           | Iir_Kind_Reduction_Nor_Operator =>
            return Name_Nor;
         when Iir_Kind_Xor_Operator
           | Iir_Kind_Reduction_Xor_Operator =>
            return Name_Xor;
         when Iir_Kind_Xnor_Operator
           | Iir_Kind_Reduction_Xnor_Operator =>
            return Name_Xnor;

         when Iir_Kind_Equality_Operator =>
            return Name_Op_Equality;
         when Iir_Kind_Inequality_Operator =>
            return Name_Op_Inequality;
         when Iir_Kind_Less_Than_Operator =>
            return Name_Op_Less;
         when Iir_Kind_Less_Than_Or_Equal_Operator =>
            return Name_Op_Less_Equal;
         when Iir_Kind_Greater_Than_Operator =>
            return Name_Op_Greater;
         when Iir_Kind_Greater_Than_Or_Equal_Operator =>
            return Name_Op_Greater_Equal;

         when Iir_Kind_Match_Equality_Operator =>
            return Name_Op_Match_Equality;
         when Iir_Kind_Match_Inequality_Operator =>
            return Name_Op_Match_Inequality;
         when Iir_Kind_Match_Less_Than_Operator =>
            return Name_Op_Match_Less;
         when Iir_Kind_Match_Less_Than_Or_Equal_Operator =>
            return Name_Op_Match_Less_Equal;
         when Iir_Kind_Match_Greater_Than_Operator =>
            return Name_Op_Match_Greater;
         when Iir_Kind_Match_Greater_Than_Or_Equal_Operator =>
            return Name_Op_Match_Greater_Equal;

         when Iir_Kind_Sll_Operator =>
            return Name_Sll;
         when Iir_Kind_Sla_Operator =>
            return Name_Sla;
         when Iir_Kind_Srl_Operator =>
            return Name_Srl;
         when Iir_Kind_Sra_Operator =>
            return Name_Sra;
         when Iir_Kind_Rol_Operator =>
            return Name_Rol;
         when Iir_Kind_Ror_Operator =>
            return Name_Ror;
         when Iir_Kind_Addition_Operator =>
            return Name_Op_Plus;
         when Iir_Kind_Substraction_Operator =>
            return Name_Op_Minus;
         when Iir_Kind_Concatenation_Operator =>
            return Name_Op_Concatenation;
         when Iir_Kind_Multiplication_Operator =>
            return Name_Op_Mul;
         when Iir_Kind_Division_Operator =>
            return Name_Op_Div;
         when Iir_Kind_Modulus_Operator =>
            return Name_Mod;
         when Iir_Kind_Remainder_Operator =>
            return Name_Rem;
         when Iir_Kind_Exponentiation_Operator =>
            return Name_Op_Exp;
         when Iir_Kind_Not_Operator =>
            return Name_Not;
         when Iir_Kind_Negation_Operator =>
            return Name_Op_Minus;
         when Iir_Kind_Identity_Operator =>
            return Name_Op_Plus;
         when Iir_Kind_Absolute_Operator =>
            return Name_Abs;
         when Iir_Kind_Condition_Operator
           | Iir_Kind_Implicit_Condition_Operator =>
            return Name_Op_Condition;
         when others =>
            raise Internal_Error;
      end case;
   end Get_Operator_Name;

   function Get_Longuest_Static_Prefix (Expr: Iir) return Iir is
      Adecl: Iir;
   begin
      Adecl := Expr;
      loop
         case Get_Kind (Adecl) is
            when Iir_Kind_Variable_Declaration
              | Iir_Kind_Interface_Variable_Declaration =>
               return Adecl;
            when Iir_Kind_Constant_Declaration
              | Iir_Kind_Interface_Constant_Declaration =>
               return Adecl;
            when Iir_Kind_Signal_Declaration
              | Iir_Kind_Guard_Signal_Declaration
              | Iir_Kind_Interface_Signal_Declaration =>
               return Adecl;
            when Iir_Kind_Object_Alias_Declaration =>
               --  LRM 4.3.3.1 Object Aliases
               --  2.  The name must be a static name [...]
               return Adecl;
            when Iir_Kind_Slice_Name
              | Iir_Kind_Indexed_Name
              | Iir_Kind_Selected_Element =>
               if Get_Name_Staticness (Adecl) >= Globally then
                  return Adecl;
               else
                  Adecl := Get_Prefix (Adecl);
               end if;
            when Iir_Kind_Simple_Name
              | Iir_Kind_Selected_Name =>
               Adecl := Get_Named_Entity (Adecl);
            when Iir_Kind_Type_Conversion =>
               return Null_Iir;
            when others =>
               Error_Kind ("get_longuest_static_prefix", Adecl);
         end case;
      end loop;
   end Get_Longuest_Static_Prefix;

   function Get_Object_Prefix (Name: Iir; With_Alias : Boolean := True)
                              return Iir
   is
      Adecl : Iir;
   begin
      Adecl := Name;
      loop
         case Get_Kind (Adecl) is
            when Iir_Kind_Variable_Declaration
              | Iir_Kind_Interface_Variable_Declaration
              | Iir_Kind_Constant_Declaration
              | Iir_Kind_Interface_Constant_Declaration
              | Iir_Kind_Signal_Declaration
              | Iir_Kind_Guard_Signal_Declaration
              | Iir_Kind_Interface_Signal_Declaration
              | Iir_Kind_File_Declaration
              | Iir_Kind_Interface_File_Declaration
              | Iir_Kind_Iterator_Declaration
              | Iir_Kind_Through_Quantity_Declaration
              | Iir_Kind_Across_Quantity_Declaration
              | Iir_Kind_Free_Quantity_Declaration
              | Iir_Kind_Terminal_Declaration
              | Iir_Kind_Interface_Type_Declaration
              | Iir_Kind_Interface_Package_Declaration
              | Iir_Kind_Interface_Function_Declaration
              | Iir_Kind_Interface_Procedure_Declaration
              | Iir_Kind_External_Signal_Name
              | Iir_Kind_External_Constant_Name
              | Iir_Kind_External_Variable_Name =>
               return Adecl;
            when Iir_Kind_Object_Alias_Declaration =>
               if With_Alias then
                  Adecl := Get_Name (Adecl);
               else
                  return Adecl;
               end if;
            when Iir_Kind_Indexed_Name
              | Iir_Kind_Slice_Name
              | Iir_Kind_Selected_Element
              | Iir_Kind_Selected_By_All_Name =>
               Adecl := Get_Base_Name (Adecl);
            when Iir_Kinds_Literal
              | Iir_Kind_Overflow_Literal
              | Iir_Kind_Enumeration_Literal
              | Iir_Kinds_Monadic_Operator
              | Iir_Kinds_Dyadic_Operator
              | Iir_Kind_Function_Call
              | Iir_Kind_Qualified_Expression
              | Iir_Kind_Type_Conversion
              | Iir_Kind_Allocator_By_Expression
              | Iir_Kind_Allocator_By_Subtype
              | Iir_Kind_Parenthesis_Expression
              | Iir_Kinds_Attribute
              | Iir_Kind_Attribute_Value
              | Iir_Kind_Aggregate
              | Iir_Kind_Simple_Aggregate
              | Iir_Kind_Dereference
              | Iir_Kind_Implicit_Dereference
              | Iir_Kind_Unit_Declaration
              | Iir_Kind_Psl_Expression
              | Iir_Kinds_Concurrent_Statement
              | Iir_Kinds_Sequential_Statement
              | Iir_Kind_Simple_Simultaneous_Statement =>
               return Adecl;
            when Iir_Kind_Simple_Name
              | Iir_Kind_Selected_Name =>
               Adecl := Get_Named_Entity (Adecl);
            when Iir_Kind_Attribute_Name =>
               return Get_Named_Entity (Adecl);
            when Iir_Kind_Error
              | Iir_Kind_Unused
              | Iir_Kind_Parenthesis_Name
              | Iir_Kind_Conditional_Expression
              | Iir_Kind_Character_Literal
              | Iir_Kind_Operator_Symbol
              | Iir_Kind_Design_File
              | Iir_Kind_Design_Unit
              | Iir_Kind_Library_Clause
              | Iir_Kind_Use_Clause
              | Iir_Kind_Context_Reference
              | Iir_Kind_Library_Declaration
              | Iir_Kinds_Library_Unit
              | Iir_Kind_Component_Declaration
              | Iir_Kind_Function_Declaration
              | Iir_Kind_Procedure_Declaration
              | Iir_Kind_Attribute_Declaration
              | Iir_Kind_Nature_Declaration
              | Iir_Kind_Subnature_Declaration
              | Iir_Kinds_Type_Declaration
              | Iir_Kinds_Type_And_Subtype_Definition
              | Iir_Kind_Wildcard_Type_Definition
              | Iir_Kind_Subtype_Definition
              | Iir_Kind_Scalar_Nature_Definition
              | Iir_Kind_Group_Template_Declaration
              | Iir_Kind_Group_Declaration
              | Iir_Kind_Signal_Attribute_Declaration
              | Iir_Kind_Unaffected_Waveform
              | Iir_Kind_Waveform_Element
              | Iir_Kind_Conditional_Waveform
              | Iir_Kind_Binding_Indication
              | Iir_Kind_Component_Configuration
              | Iir_Kind_Block_Configuration
              | Iir_Kind_Attribute_Specification
              | Iir_Kind_Disconnection_Specification
              | Iir_Kind_Configuration_Specification
              | Iir_Kind_Non_Object_Alias_Declaration
              | Iir_Kinds_Subprogram_Body
              | Iir_Kind_Protected_Type_Body
              | Iir_Kind_Generate_Statement_Body
              | Iir_Kind_Procedure_Call
              | Iir_Kind_Aggregate_Info
              | Iir_Kind_Entity_Class
              | Iir_Kind_Signature
              | Iir_Kind_Reference_Name
              | Iir_Kind_Package_Header
              | Iir_Kind_Block_Header
              | Iir_Kinds_Association_Element
              | Iir_Kind_Association_Element_Package
              | Iir_Kind_Association_Element_Type
              | Iir_Kind_Association_Element_Subprogram
              | Iir_Kinds_Choice
              | Iir_Kinds_Entity_Aspect
              | Iir_Kind_If_Generate_Else_Clause
              | Iir_Kind_Elsif
              | Iir_Kind_Record_Element_Constraint
              | Iir_Kind_Array_Element_Resolution
              | Iir_Kind_Record_Resolution
              | Iir_Kind_Record_Element_Resolution
              | Iir_Kind_Element_Declaration
              | Iir_Kind_Psl_Endpoint_Declaration
              | Iir_Kind_Psl_Declaration
              | Iir_Kind_Package_Pathname
              | Iir_Kind_Absolute_Pathname
              | Iir_Kind_Relative_Pathname
              | Iir_Kind_Pathname_Element
              | Iir_Kind_Range_Expression
              | Iir_Kind_Overload_List =>
               return Adecl;
         end case;
      end loop;
   end Get_Object_Prefix;

   function Is_Object_Name (Name : Iir) return Boolean
   is
      Obj : constant Iir := Name_To_Object (Name);
   begin
      return Obj /= Null_Iir;
   end Is_Object_Name;

   function Name_To_Object (Name : Iir) return Iir is
   begin
      --  LRM08 6.4 Objects
      --  An object is a named entity that contains (has) a value of a type.
      --  An object is obe of the following:
      case Get_Kind (Name) is
         --  An object declared by an object declaration (see 6.4.2)
         when Iir_Kind_Signal_Declaration
           | Iir_Kind_Variable_Declaration
           | Iir_Kind_File_Declaration
           | Iir_Kind_Constant_Declaration =>
            return Name;

         --  A loop of generate parameter.
         when Iir_Kind_Iterator_Declaration =>
            return Name;

         --  A formal parameter of a subprogram
         --  A formal port
         --  A formal generic constant
         --  A local port
         --  A local generic constant
         when Iir_Kind_Interface_Constant_Declaration
           | Iir_Kind_Interface_Variable_Declaration
           | Iir_Kind_Interface_Signal_Declaration
           | Iir_Kind_Interface_File_Declaration =>
            return Name;

         --  An implicit signak GUARD defined by the guard expression of a
         --   block statement
         when Iir_Kind_Guard_Signal_Declaration =>
            return Name;

         --  In addition, the following are objects [ but are not named
         --   entities]:
         --  An implicit signal defined by any of the predefined attributes
         --  'DELAYED, 'STABLE, 'QUIET, and 'TRANSACTION
         when Iir_Kinds_Signal_Attribute =>
            return Name;

         --  An element or a slice of another object
         when Iir_Kind_Slice_Name
           | Iir_Kind_Indexed_Name
           | Iir_Kind_Selected_Element =>
            return Name;

         --  An object designated by a value of an access type
         when Iir_Kind_Implicit_Dereference
           | Iir_Kind_Dereference =>
            return Name;

         --  LRM08 6.6 Alias declarations
         --  An object alias is an alias whose alias designatore denotes an
         --  object.
         when Iir_Kind_Object_Alias_Declaration =>
            return Name;

         when Iir_Kind_Simple_Name
           | Iir_Kind_Selected_Name =>
            --  LRM08 8 Names
            --  Names can denote declared entities [...]
            --  GHDL: in particular, names can denote objects.
            return Name_To_Object (Get_Named_Entity (Name));

         when Iir_Kinds_External_Name =>
            return Name;

         when others =>
            return Null_Iir;
      end case;
   end Name_To_Object;

   function Name_To_Value (Name : Iir) return Iir is
   begin
      case Get_Kind (Name) is
         when Iir_Kind_Attribute_Value
           | Iir_Kind_Function_Call
           | Iir_Kinds_Expression_Attribute =>
            return Name;
         when Iir_Kind_Simple_Name
           | Iir_Kind_Selected_Name =>
            return Name_To_Value (Get_Named_Entity (Name));
         when others =>
            return Name_To_Object (Name);
      end case;
   end Name_To_Value;

   --  Return TRUE if EXPR is a signal name.
   function Is_Signal_Name (Expr : Iir) return Boolean
   is
      Obj : Iir;
   begin
      Obj := Name_To_Object (Expr);
      if Obj /= Null_Iir then
         return Is_Signal_Object (Obj);
      else
         return False;
      end if;
   end Is_Signal_Name;

   function Is_Signal_Object (Name : Iir) return Boolean
   is
      Adecl: Iir;
   begin
      Adecl := Get_Object_Prefix (Name, True);
      case Get_Kind (Adecl) is
         when Iir_Kind_Signal_Declaration
           | Iir_Kind_Interface_Signal_Declaration
           | Iir_Kind_Guard_Signal_Declaration
           | Iir_Kinds_Signal_Attribute =>
            return True;
         when Iir_Kind_Object_Alias_Declaration =>
            --  Must have been handled by Get_Object_Prefix.
            raise Internal_Error;
         when others =>
            return False;
      end case;
   end Is_Signal_Object;

   function Get_Interface_Of_Formal (Formal : Iir) return Iir
   is
      El : Iir;
   begin
      El := Formal;
      loop
         case Get_Kind (El) is
            when Iir_Kind_Simple_Name
              | Iir_Kind_Operator_Symbol =>
               --  Operator is for subprogram interfaces.
               return Get_Named_Entity (El);
            when Iir_Kinds_Interface_Declaration =>
               return El;
            when Iir_Kind_Slice_Name
              | Iir_Kind_Indexed_Name
              | Iir_Kind_Selected_Element =>
               --  FIXME: use get_base_name ?
               El := Get_Prefix (El);
            when others =>
               Error_Kind ("get_interface_of_formal", El);
         end case;
      end loop;
   end Get_Interface_Of_Formal;

   function Get_Association_Interface (Assoc : Iir; Inter : Iir) return Iir
   is
      Formal : constant Iir := Get_Formal (Assoc);
   begin
      if Formal /= Null_Iir then
         return Get_Interface_Of_Formal (Formal);
      else
         return Inter;
      end if;
   end Get_Association_Interface;

   procedure Next_Association_Interface
     (Assoc : in out Iir; Inter : in out Iir)
   is
      Formal : constant Iir := Get_Formal (Assoc);
   begin
      --  In canon, open association can be inserted after an association by
      --  name.  So do not assume there is no association by position after
      --  association by name.
      if Is_Valid (Formal) then
         Inter := Get_Chain (Get_Interface_Of_Formal (Formal));
      else
         Inter := Get_Chain (Inter);
      end if;
      Assoc := Get_Chain (Assoc);
   end Next_Association_Interface;

   function Get_Association_Formal (Assoc : Iir; Inter : Iir) return Iir
   is
      Formal : constant Iir := Get_Formal (Assoc);
   begin
      if Formal /= Null_Iir then
         --  Strip denoting name
         case Get_Kind (Formal) is
            when Iir_Kind_Simple_Name
              | Iir_Kind_Operator_Symbol =>
               return Get_Named_Entity (Formal);
            when Iir_Kinds_Interface_Declaration =>
               --  Shouldn't happen.
               raise Internal_Error;
            when Iir_Kind_Slice_Name
              | Iir_Kind_Indexed_Name
              | Iir_Kind_Selected_Element =>
               return Formal;
            when others =>
               Error_Kind ("get_association_formal", Formal);
         end case;
      else
         return Inter;
      end if;
   end Get_Association_Formal;

   function Find_First_Association_For_Interface
     (Assoc_Chain : Iir; Inter_Chain : Iir; Inter : Iir) return Iir
   is
      Assoc_El : Iir;
      Inter_El : Iir;
   begin
      Assoc_El := Assoc_Chain;
      Inter_El := Inter_Chain;
      while Is_Valid (Assoc_El) loop
         if Get_Association_Interface (Assoc_El, Inter_El) = Inter then
            return Assoc_El;
         end if;
         Next_Association_Interface (Assoc_El, Inter_El);
      end loop;
      return Null_Iir;
   end Find_First_Association_For_Interface;

   function Is_Parameter (Inter : Iir) return Boolean is
   begin
      case Get_Kind (Get_Parent (Inter)) is
         when Iir_Kinds_Subprogram_Declaration
           | Iir_Kinds_Interface_Subprogram_Declaration =>
            return True;
         when others =>
            --  Port
            return False;
      end case;
   end Is_Parameter;

   function Find_Name_In_Flist (List : Iir_Flist; Lit : Name_Id) return Iir
   is
      El : Iir;
   begin
      for I in Flist_First .. Flist_Last (List) loop
         El := Get_Nth_Element (List, I);
         if Get_Identifier (El) = Lit then
            return El;
         end if;
      end loop;
      return Null_Iir;
   end Find_Name_In_Flist;

   function Find_Name_In_Chain (Chain: Iir; Lit: Name_Id) return Iir
   is
      El: Iir := Chain;
   begin
      while El /= Null_Iir loop
         if Get_Identifier (El) = Lit then
            return El;
         end if;
         El := Get_Chain (El);
      end loop;
      return Null_Iir;
   end Find_Name_In_Chain;

   function Is_In_Chain (Chain : Iir; El : Iir) return Boolean
   is
      Chain_El : Iir;
   begin
      Chain_El := Chain;
      while Chain_El /= Null_Iir loop
         if Chain_El = El then
            return True;
         end if;
         Chain_El := Get_Chain (Chain_El);
      end loop;
      return False;
   end Is_In_Chain;

   procedure Add_Dependence (Target: Iir_Design_Unit; Unit: Iir) is
   begin
      --  Do not add self-dependency
      if Unit = Target then
         return;
      end if;

      pragma Assert (Kind_In (Unit, Iir_Kind_Design_Unit,
                              Iir_Kind_Entity_Aspect_Entity));

      Add_Element (Get_Dependence_List (Target), Unit);
   end Add_Dependence;

   function Get_Unit_From_Dependence (Dep : Iir) return Iir is
   begin
      case Get_Kind (Dep) is
         when Iir_Kind_Design_Unit =>
            return Dep;
         when Iir_Kind_Entity_Aspect_Entity =>
            return Get_Design_Unit (Get_Entity (Dep));
         when others =>
            Error_Kind ("get_unit_from_dependence", Dep);
      end case;
   end Get_Unit_From_Dependence;

   procedure Clear_Instantiation_Configuration_Vhdl87
     (Parent : Iir; In_Generate : Boolean; Full : Boolean)
   is
      El : Iir;
      Prev : Iir;
   begin
      El := Get_Concurrent_Statement_Chain (Parent);
      while El /= Null_Iir loop
         case Get_Kind (El) is
            when Iir_Kind_Component_Instantiation_Statement =>
               if In_Generate and not Full then
                  Prev := Get_Component_Configuration (El);
                  if Prev /= Null_Iir then
                     case Get_Kind (Prev) is
                        when Iir_Kind_Configuration_Specification =>
                           --  Keep it.
                           null;
                        when Iir_Kind_Component_Configuration =>
                           Set_Component_Configuration (El, Null_Iir);
                        when others =>
                           Error_Kind
                             ("clear_instantiation_configuration_vhdl87",
                              Prev);
                     end case;
                  end if;
               else
                  Set_Component_Configuration (El, Null_Iir);
               end if;
            when Iir_Kind_For_Generate_Statement =>
               Set_Generate_Block_Configuration (El, Null_Iir);
               --  Clear inside a generate statement.
               Clear_Instantiation_Configuration_Vhdl87 (El, True, Full);
            when Iir_Kind_Block_Statement =>
               Set_Block_Block_Configuration (El, Null_Iir);
            when others =>
               null;
         end case;
         El := Get_Chain (El);
      end loop;
   end Clear_Instantiation_Configuration_Vhdl87;

   procedure Clear_Instantiation_Configuration (Parent : Iir; Full : Boolean)
   is
      El : Iir;
   begin
      if False and then Flags.Vhdl_Std = Vhdl_87 then
         Clear_Instantiation_Configuration_Vhdl87
           (Parent, Get_Kind (Parent) = Iir_Kind_For_Generate_Statement, Full);
      else
         El := Get_Concurrent_Statement_Chain (Parent);
         while El /= Null_Iir loop
            case Get_Kind (El) is
               when Iir_Kind_Component_Instantiation_Statement =>
                  Set_Component_Configuration (El, Null_Iir);
               when Iir_Kind_For_Generate_Statement =>
                  declare
                     Bod : constant Iir := Get_Generate_Statement_Body (El);
                  begin
                     Set_Generate_Block_Configuration (Bod, Null_Iir);
                  end;
               when Iir_Kind_If_Generate_Statement =>
                  declare
                     Clause : Iir;
                     Bod : Iir;
                  begin
                     Clause := El;
                     while Clause /= Null_Iir loop
                        Bod := Get_Generate_Statement_Body (Clause);
                        Set_Generate_Block_Configuration (Bod, Null_Iir);
                        Clause := Get_Generate_Else_Clause (Clause);
                     end loop;
                  end;
               when Iir_Kind_Block_Statement =>
                  Set_Block_Block_Configuration (El, Null_Iir);
               when others =>
                  null;
            end case;
            El := Get_Chain (El);
         end loop;
      end if;
   end Clear_Instantiation_Configuration;

   --  Get identifier of NODE as a string.
   function Image_Identifier (Node : Iir) return String is
   begin
      return Name_Table.Image (Vhdl.Nodes.Get_Identifier (Node));
   end Image_Identifier;

   function Image_String_Lit (Str : Iir) return String is
   begin
      return Str_Table.String_String8
        (Get_String8_Id (Str), Get_String_Length (Str));
   end Image_String_Lit;

   function Copy_Enumeration_Literal (Lit : Iir) return Iir
   is
      Res : Iir;
   begin
      Res := Create_Iir (Iir_Kind_Enumeration_Literal);
      Set_Identifier (Res, Get_Identifier (Lit));
      Location_Copy (Res, Lit);
      Set_Parent (Res, Get_Parent (Lit));
      Set_Type (Res, Get_Type (Lit));
      Set_Enum_Pos (Res, Get_Enum_Pos (Lit));
      Set_Expr_Staticness (Res, Locally);
      return Res;
   end Copy_Enumeration_Literal;

   procedure Create_Range_Constraint_For_Enumeration_Type
     (Def : Iir_Enumeration_Type_Definition)
   is
      Range_Expr : Iir_Range_Expression;
      Literal_List : constant Iir_Flist := Get_Enumeration_Literal_List (Def);
      List_Len : constant Natural := Get_Nbr_Elements (Literal_List);
   begin
      --  Create a constraint.
      Range_Expr := Create_Iir (Iir_Kind_Range_Expression);
      Location_Copy (Range_Expr, Def);
      Set_Type (Range_Expr, Def);
      Set_Direction (Range_Expr, Iir_To);
      if List_Len >= 1 then
         Set_Left_Limit
           (Range_Expr, Get_Nth_Element (Literal_List, 0));
         Set_Right_Limit
           (Range_Expr, Get_Nth_Element (Literal_List, List_Len - 1));
      end if;
      Set_Expr_Staticness (Range_Expr, Locally);
      Set_Range_Constraint (Def, Range_Expr);
   end Create_Range_Constraint_For_Enumeration_Type;

   function Is_Static_Construct (Expr : Iir) return Boolean is
   begin
      case Get_Kind (Expr) is
         when Iir_Kind_Aggregate =>
            return Get_Aggregate_Expand_Flag (Expr);
         when Iir_Kinds_Literal =>
            return True;
         when Iir_Kind_Simple_Aggregate
           | Iir_Kind_Enumeration_Literal
           | Iir_Kind_Character_Literal =>
            return True;
         when Iir_Kind_Overflow_Literal =>
            --  Needs to generate an error.
            return False;
         when others =>
            return False;
      end case;
   end Is_Static_Construct;

   procedure Free_Name (Node : Iir)
   is
      N : Iir;
      N1 : Iir;
   begin
      if Node = Null_Iir then
         return;
      end if;
      N := Node;
      case Get_Kind (N) is
         when Iir_Kind_Simple_Name
           | Iir_Kind_Character_Literal
           | Iir_Kind_String_Literal8
           | Iir_Kind_Subtype_Definition =>
            Free_Iir (N);
         when Iir_Kind_Selected_Name
           | Iir_Kind_Parenthesis_Name
           | Iir_Kind_Selected_By_All_Name =>
            N1 := Get_Prefix (N);
            Free_Iir (N);
            Free_Name (N1);
         when Iir_Kind_Library_Declaration
           | Iir_Kind_Package_Declaration
           | Iir_Kind_Entity_Declaration
           | Iir_Kind_Architecture_Body
           | Iir_Kind_Design_Unit
           | Iir_Kinds_Concurrent_Statement
           | Iir_Kinds_Sequential_Statement =>
            return;
         when others =>
            Error_Kind ("free_name", Node);
            --Free_Iir (N);
      end case;
   end Free_Name;

   procedure Free_Recursive_List (List : Iir_List)
   is
      It : List_Iterator;
   begin
      It := List_Iterate (List);
      while Is_Valid (It) loop
         Free_Recursive (Get_Element (It));
         Next (It);
      end loop;
   end Free_Recursive_List;

   procedure Free_Recursive_Flist (List : Iir_Flist)
   is
      El : Iir;
   begin
      for I in Flist_First .. Flist_Last (List) loop
         El := Get_Nth_Element (List, I);
         Free_Recursive (El);
      end loop;
   end Free_Recursive_Flist;

   procedure Free_Recursive (Node : Iir; Free_List : Boolean := False)
   is
      N : Iir;
   begin
      if Node = Null_Iir then
         return;
      end if;
      N := Node;
      case Get_Kind (N) is
         when Iir_Kind_Library_Declaration =>
            return;
         when Iir_Kind_Simple_Name
           | Iir_Kind_Parenthesis_Name
           | Iir_Kind_Character_Literal =>
            null;
         when Iir_Kind_Enumeration_Literal =>
            return;
         when Iir_Kind_Selected_Name =>
            Free_Recursive (Get_Prefix (N));
         when Iir_Kind_Interface_Constant_Declaration
           | Iir_Kind_Interface_Variable_Declaration
           | Iir_Kind_Interface_Signal_Declaration =>
            Free_Recursive (Get_Type (N));
            Free_Recursive (Get_Default_Value (N));
         when Iir_Kind_Range_Expression =>
            Free_Recursive (Get_Left_Limit (N));
            Free_Recursive (Get_Right_Limit (N));
         when Iir_Kind_Subtype_Definition =>
            Free_Recursive (Get_Base_Type (N));
         when Iir_Kind_Integer_Literal =>
            null;
         when Iir_Kind_Package_Declaration
           | Iir_Kind_Package_Body
           | Iir_Kind_Entity_Declaration
           | Iir_Kind_Configuration_Declaration
           | Iir_Kind_Context_Declaration =>
            null;
         when Iir_Kind_File_Type_Definition
           | Iir_Kind_Access_Type_Definition
           | Iir_Kind_Array_Type_Definition
           | Iir_Kind_Enumeration_Type_Definition
           | Iir_Kind_Integer_Subtype_Definition
           | Iir_Kind_Enumeration_Subtype_Definition
           | Iir_Kind_Physical_Subtype_Definition =>
            return;
         when Iir_Kind_Architecture_Body =>
            Free_Recursive (Get_Entity_Name (N));
         when Iir_Kind_Overload_List =>
            Free_Recursive_List (Get_Overload_List (N));
            if not Free_List then
               return;
            end if;
         when Iir_Kind_Array_Subtype_Definition =>
            Free_Recursive_Flist (Get_Index_List (N));
            Free_Recursive (Get_Base_Type (N));
         when Iir_Kind_Entity_Aspect_Entity =>
            Free_Recursive (Get_Entity (N));
            Free_Recursive (Get_Architecture (N));
         when others =>
            Error_Kind ("free_recursive", Node);
      end case;
      Free_Iir (N);
   end Free_Recursive;

   function Get_Predefined_Function_Name (Func : Iir_Predefined_Functions)
                                          return String
   is
   begin
      return Iir_Predefined_Functions'Image (Func);
   end Get_Predefined_Function_Name;

   function Get_Callees_List_Holder (Subprg : Iir) return Iir is
   begin
      case Get_Kind (Subprg) is
         when Iir_Kind_Procedure_Declaration
           | Iir_Kind_Function_Declaration =>
            return Get_Subprogram_Body (Subprg);
         when Iir_Kind_Sensitized_Process_Statement
           | Iir_Kind_Process_Statement =>
            return Subprg;
         when others =>
            Error_Kind ("get_callees_list_holder", Subprg);
      end case;
   end Get_Callees_List_Holder;

   procedure Clear_Seen_Flag (Top : Iir)
   is
      Callees_List : Iir_Callees_List;
      It : List_Iterator;
      El: Iir;
   begin
      if Get_Seen_Flag (Top) then
         Set_Seen_Flag (Top, False);
         Callees_List := Get_Callees_List (Get_Callees_List_Holder (Top));
         if Callees_List /= Null_Iir_List then
            It := List_Iterate (Callees_List);
            while Is_Valid (It) loop
               El := Get_Element (It);
               if Get_Seen_Flag (El) = False then
                  Clear_Seen_Flag (El);
               end if;
               Next (It);
            end loop;
         end if;
      end if;
   end Clear_Seen_Flag;

   function Is_Anonymous_Type_Definition (Def : Iir) return Boolean is
   begin
      return Get_Type_Declarator (Def) = Null_Iir;
   end Is_Anonymous_Type_Definition;

   function Is_Fully_Constrained_Type (Def : Iir) return Boolean is
   begin
      return Get_Kind (Def) not in Iir_Kinds_Composite_Type_Definition
        or else Get_Constraint_State (Def) = Fully_Constrained;
   end Is_Fully_Constrained_Type;

   function Strip_Denoting_Name (Name : Iir) return Iir is
   begin
      if Get_Kind (Name) in Iir_Kinds_Denoting_Name then
         return Get_Named_Entity (Name);
      else
         return Name;
      end if;
   end Strip_Denoting_Name;

   function Build_Simple_Name (Ref : Iir; Loc : Location_Type) return Iir
   is
      Res : Iir;
   begin
      Res := Create_Iir (Iir_Kind_Simple_Name);
      Set_Location (Res, Loc);
      Set_Identifier (Res, Get_Identifier (Ref));
      Set_Named_Entity (Res, Ref);
      Set_Base_Name (Res, Res);
      --  FIXME: set type and expr staticness ?
      return Res;
   end Build_Simple_Name;

   function Build_Simple_Name (Ref : Iir; Loc : Iir) return Iir is
   begin
      return Build_Simple_Name (Ref, Get_Location (Loc));
   end Build_Simple_Name;

   function Build_Reference_Name (Name : Iir) return Iir
   is
      Res : Iir;
   begin
      pragma Assert (Get_Kind (Name) in Iir_Kinds_Denoting_Name);

      Res := Create_Iir (Iir_Kind_Reference_Name);
      Location_Copy (Res, Name);
      Set_Referenced_Name (Res, Name);
      Set_Is_Forward_Ref (Res, True);
      Set_Named_Entity (Res, Get_Named_Entity (Name));
      return Res;
   end Build_Reference_Name;

   function Strip_Reference_Name (N : Iir) return Iir is
   begin
      if Get_Kind (N) = Iir_Kind_Reference_Name then
         return Get_Named_Entity (N);
      else
         return N;
      end if;
   end Strip_Reference_Name;

   function Has_Resolution_Function (Subtyp : Iir) return Iir
   is
      Ind : constant Iir := Get_Resolution_Indication (Subtyp);
   begin
      if Ind /= Null_Iir
        and then Get_Kind (Ind) in Iir_Kinds_Denoting_Name
      then
         --  A resolution indication can be an array/record element resolution.
         return Get_Named_Entity (Ind);
      else
         return Null_Iir;
      end if;
   end Has_Resolution_Function;

   function Is_Type_Name (Name : Iir) return Iir
   is
      Ent : Iir;
   begin
      if Get_Kind (Name) in Iir_Kinds_Denoting_Name then
         Ent := Get_Named_Entity (Name);
         case Get_Kind (Ent) is
            when Iir_Kind_Type_Declaration =>
               return Get_Type_Definition (Ent);
            when Iir_Kind_Subtype_Declaration
              | Iir_Kind_Base_Attribute =>
               return Get_Type (Ent);
            when others =>
               return Null_Iir;
         end case;
      else
         return Null_Iir;
      end if;
   end Is_Type_Name;

   function Get_Type_Of_Subtype_Indication (Ind : Iir) return Iir is
   begin
      case Get_Kind (Ind) is
         when Iir_Kinds_Denoting_Name =>
            return Get_Type (Ind);
         when Iir_Kinds_Subtype_Definition =>
            return Ind;
         when Iir_Kind_Subtype_Attribute =>
            return Get_Type (Ind);
         when Iir_Kind_Error =>
            return Ind;
         when others =>
            Error_Kind ("get_type_of_subtype_indication", Ind);
      end case;
   end Get_Type_Of_Subtype_Indication;

   function Get_Index_Type (Indexes : Iir_Flist; Idx : Natural) return Iir
   is
      Index : constant Iir := Get_Nth_Element (Indexes, Idx);
   begin
      if Index = Null_Iir then
         return Null_Iir;
      else
         return Get_Index_Type (Index);
      end if;
   end Get_Index_Type;

   function Get_Index_Type (Array_Type : Iir; Idx : Natural) return Iir is
   begin
      return Get_Index_Type (Get_Index_Subtype_List (Array_Type), Idx);
   end Get_Index_Type;

   function Get_Nbr_Dimensions (Array_Type : Iir) return Natural is
   begin
      return Get_Nbr_Elements (Get_Index_Subtype_List (Array_Type));
   end Get_Nbr_Dimensions;

   function Are_Array_Indexes_Locally_Static (Array_Type : Iir) return Boolean
   is
      Indexes : constant Iir_Flist := Get_Index_Subtype_List (Array_Type);
      Index : Iir;
   begin
      for I in Flist_First .. Flist_Last (Indexes) loop
         Index := Get_Index_Type (Indexes, I);
         if Get_Type_Staticness (Index) /= Locally then
            return False;
         end if;
      end loop;
      return True;
   end Are_Array_Indexes_Locally_Static;

   function Are_Bounds_Locally_Static (Def : Iir) return Boolean is
   begin
      if Get_Type_Staticness (Def) = Locally then
         return True;
      end if;

      case Iir_Kinds_Type_And_Subtype_Definition (Get_Kind (Def)) is
         when Iir_Kind_Array_Subtype_Definition =>
            pragma Assert (Get_Constraint_State (Def) = Fully_Constrained);

            --  Indexes.
            if not Are_Array_Indexes_Locally_Static (Def) then
               return False;
            end if;

            --  Element.
            return Are_Bounds_Locally_Static (Get_Element_Subtype (Def));
         when Iir_Kind_Array_Type_Definition =>
            return False;
         when Iir_Kind_Record_Subtype_Definition
           | Iir_Kind_Record_Type_Definition =>
            pragma Assert (Get_Constraint_State (Def) = Fully_Constrained);

            declare
               El_List : constant Iir_Flist :=
                 Get_Elements_Declaration_List (Def);
               El : Iir;
            begin
               for I in Flist_First .. Flist_Last (El_List) loop
                  El := Get_Nth_Element (El_List, I);
                  if not Are_Bounds_Locally_Static (Get_Type (El)) then
                     return False;
                  end if;
               end loop;
               return True;
            end;
         when Iir_Kinds_Scalar_Type_And_Subtype_Definition
           | Iir_Kind_Protected_Type_Declaration
           | Iir_Kind_Access_Type_Definition
           | Iir_Kind_Access_Subtype_Definition =>
            return True;
         when Iir_Kind_Incomplete_Type_Definition
           | Iir_Kind_File_Type_Definition
           | Iir_Kind_Interface_Type_Definition =>
            Error_Kind ("are_bounds_locally_static", Def);
      end case;
   end Are_Bounds_Locally_Static;

   function Get_Denoted_Type_Mark (Subtyp : Iir) return Iir
   is
      Type_Mark_Name : constant Iir := Get_Subtype_Type_Mark (Subtyp);
   begin
      if Type_Mark_Name = Null_Iir then
         --  No type_mark (for array subtype created by constrained array
         --  definition.
         return Null_Iir;
      else
         return Get_Type (Get_Named_Entity (Type_Mark_Name));
      end if;
   end Get_Denoted_Type_Mark;

   function Get_Base_Element_Declaration (El : Iir) return Iir
   is
      Rec_Type : constant Iir := Get_Base_Type (Get_Parent (El));
      Els_List : constant Iir_Flist :=
        Get_Elements_Declaration_List (Rec_Type);
   begin
      return Get_Nth_Element
        (Els_List, Natural (Get_Element_Position (El)));
   end Get_Base_Element_Declaration;

   procedure Append_Owned_Element_Constraint (Rec_Type : Iir; El : Iir) is
   begin
      pragma Assert (Get_Parent (El) = Rec_Type);
      Set_Chain (El, Get_Owned_Elements_Chain (Rec_Type));
      Set_Owned_Elements_Chain (Rec_Type, El);
   end Append_Owned_Element_Constraint;


   function Is_Second_Subprogram_Specification (Spec : Iir) return Boolean
   is
      Bod : constant Iir := Get_Chain (Spec);
   begin
      --  FIXME: don't directly use Subprogram_Body as it is not yet correctly
      --  set during instantiation.
      return Get_Has_Body (Spec)
        and then Get_Subprogram_Specification (Bod) /= Spec;
   end Is_Second_Subprogram_Specification;

   function Is_Implicit_Subprogram (Spec : Iir) return Boolean is
   begin
      return Get_Kind (Spec) in Iir_Kinds_Subprogram_Declaration
        and then Get_Implicit_Definition (Spec) in Iir_Predefined_Implicit;
   end Is_Implicit_Subprogram;

   function Is_Function_Declaration (N : Iir) return Boolean is
   begin
      return Kind_In (N, Iir_Kind_Function_Declaration,
                      Iir_Kind_Interface_Function_Declaration);
   end Is_Function_Declaration;

   function Is_Procedure_Declaration (N : Iir) return Boolean is
   begin
      return Kind_In (N, Iir_Kind_Procedure_Declaration,
                      Iir_Kind_Interface_Procedure_Declaration);
   end Is_Procedure_Declaration;

   function Is_Same_Profile (L, R: Iir) return Boolean
   is
      L1, R1 : Iir;
      L_Kind, R_Kind : Iir_Kind;
      El_L, El_R : Iir;
   begin
      L_Kind := Get_Kind (L);
      if L_Kind = Iir_Kind_Non_Object_Alias_Declaration then
         L1 := Get_Named_Entity (Get_Name (L));
         L_Kind := Get_Kind (L1);
      else
         L1 := L;
      end if;
      R_Kind := Get_Kind (R);
      if R_Kind = Iir_Kind_Non_Object_Alias_Declaration then
         R1 := Get_Named_Entity (Get_Name (R));
         R_Kind := Get_Kind (R1);
      else
         R1 := R;
      end if;

      --  Check L and R are both of the same 'kind'.
      --  Also the return profile for functions.
      if L_Kind = Iir_Kind_Function_Declaration
        and then R_Kind = Iir_Kind_Function_Declaration
      then
         if Get_Base_Type (Get_Return_Type (L1)) /=
           Get_Base_Type (Get_Return_Type (R1))
         then
            return False;
         end if;
      elsif L_Kind = Iir_Kind_Procedure_Declaration
        and then R_Kind = Iir_Kind_Procedure_Declaration
      then
         null;
      elsif L_Kind = Iir_Kind_Enumeration_Literal
        and then R_Kind = Iir_Kind_Enumeration_Literal
      then
         return Get_Type (L1) = Get_Type (R1);
      elsif L_Kind = Iir_Kind_Enumeration_Literal
        and then R_Kind = Iir_Kind_Function_Declaration
      then
         return Get_Interface_Declaration_Chain (R1) = Null_Iir
           and then Get_Base_Type (Get_Return_Type (R1)) = Get_Type (L1);
      elsif L_Kind = Iir_Kind_Function_Declaration
        and then R_Kind = Iir_Kind_Enumeration_Literal
      then
         return Get_Interface_Declaration_Chain (L1) = Null_Iir
           and then Get_Base_Type (Get_Return_Type (L1)) = Get_Type (R1);
      else
         --  Kind mismatch.
         return False;
      end if;

      --  Check parameters profile.
      El_L := Get_Interface_Declaration_Chain (L1);
      El_R := Get_Interface_Declaration_Chain (R1);
      loop
         exit when El_L = Null_Iir and El_R = Null_Iir;
         if El_L = Null_Iir or El_R = Null_Iir then
            return False;
         end if;
         if Get_Base_Type (Get_Type (El_L)) /= Get_Base_Type (Get_Type (El_R))
         then
            return False;
         end if;
         El_L := Get_Chain (El_L);
         El_R := Get_Chain (El_R);
      end loop;

      return True;
   end Is_Same_Profile;

   function Is_Operation_For_Type (Subprg : Iir; Atype : Iir) return Boolean
   is
      pragma Assert (Get_Kind (Subprg) in Iir_Kinds_Subprogram_Declaration);
      Base_Type : constant Iir := Get_Base_Type (Atype);
      Inter : Iir;
   begin
      Inter := Get_Interface_Declaration_Chain (Subprg);
      while Inter /= Null_Iir loop
         if Get_Base_Type (Get_Type (Inter)) = Base_Type then
            return True;
         end if;
         Inter := Get_Chain (Inter);
      end loop;
      if Get_Kind (Subprg) = Iir_Kind_Function_Declaration
        and then Get_Base_Type (Get_Return_Type (Subprg)) = Base_Type
      then
         return True;
      end if;
      return False;
   end Is_Operation_For_Type;

   -- From a block_specification, returns the block.
   function Get_Block_From_Block_Specification (Block_Spec : Iir)
     return Iir
   is
      Res : Iir;
   begin
      case Get_Kind (Block_Spec) is
         when Iir_Kind_Design_Unit =>
            Res := Get_Library_Unit (Block_Spec);
            if Get_Kind (Res) /= Iir_Kind_Architecture_Body then
               raise Internal_Error;
            end if;
            return Res;
         when Iir_Kind_Block_Statement
           | Iir_Kind_Architecture_Body
           | Iir_Kind_For_Generate_Statement
           | Iir_Kind_If_Generate_Statement =>
            return Block_Spec;
         when Iir_Kind_Indexed_Name
           | Iir_Kind_Selected_Name
           | Iir_Kind_Slice_Name =>
            return Get_Named_Entity (Get_Prefix (Block_Spec));
         when Iir_Kind_Simple_Name =>
            return Get_Named_Entity (Block_Spec);
         when Iir_Kind_Parenthesis_Name =>
            --  An alternative label.
            return Get_Named_Entity (Block_Spec);
         when others =>
            Error_Kind ("get_block_from_block_specification", Block_Spec);
            return Null_Iir;
      end case;
   end Get_Block_From_Block_Specification;

   function Get_Entity (Decl : Iir) return Iir
   is
      Name : constant Iir := Get_Entity_Name (Decl);
      Res : constant Iir := Get_Named_Entity (Name);
   begin
      if Res = Vhdl.Std_Package.Error_Mark then
         return Null_Iir;
      end if;

      pragma Assert (Res = Null_Iir
                       or else Get_Kind (Res) = Iir_Kind_Entity_Declaration);
      return Res;
   end Get_Entity;

   function Get_Configuration (Aspect : Iir) return Iir
   is
      Name : constant Iir := Get_Configuration_Name (Aspect);
      Res : constant Iir := Get_Named_Entity (Name);
   begin
      pragma Assert (Get_Kind (Res) = Iir_Kind_Configuration_Declaration);
      return Res;
   end Get_Configuration;

   function Get_Entity_Identifier_Of_Architecture (Arch : Iir) return Name_Id
   is
      Name : constant Iir := Get_Entity_Name (Arch);
   begin
      case Get_Kind (Name) is
         when Iir_Kind_Simple_Name
           | Iir_Kind_Selected_Name =>
            return Get_Identifier (Name);
         when Iir_Kind_Error =>
            return Null_Identifier;
         when others =>
            Error_Kind ("get_entity_identifier_of_architecture", Name);
      end case;
   end Get_Entity_Identifier_Of_Architecture;

   function Is_Component_Instantiation
     (Inst : Iir_Component_Instantiation_Statement)
     return Boolean is
   begin
      case Get_Kind (Get_Instantiated_Unit (Inst)) is
         when Iir_Kinds_Denoting_Name =>
            return True;
         when Iir_Kind_Entity_Aspect_Entity
           | Iir_Kind_Entity_Aspect_Configuration =>
            return False;
         when others =>
            Error_Kind ("is_component_instantiation", Inst);
      end case;
   end Is_Component_Instantiation;

   function Is_Entity_Instantiation
     (Inst : Iir_Component_Instantiation_Statement)
     return Boolean is
   begin
      case Get_Kind (Get_Instantiated_Unit (Inst)) is
         when Iir_Kinds_Denoting_Name =>
            return False;
         when Iir_Kind_Entity_Aspect_Entity
           | Iir_Kind_Entity_Aspect_Configuration =>
            return True;
         when others =>
            Error_Kind ("is_entity_instantiation", Inst);
      end case;
   end Is_Entity_Instantiation;

   function Get_Attribute_Name_Expression (Name : Iir) return Iir
   is
      Attr_Val : constant Iir := Get_Named_Entity (Name);
      Attr_Spec : constant Iir := Get_Attribute_Specification (Attr_Val);
      Attr_Expr : constant Iir := Get_Expression (Attr_Spec);
   begin
      return Attr_Expr;
   end Get_Attribute_Name_Expression;

   function Get_String_Type_Bound_Type (Sub_Type : Iir) return Iir is
   begin
      if Get_Kind (Sub_Type) /= Iir_Kind_Array_Subtype_Definition then
         Error_Kind ("get_string_type_bound_type", Sub_Type);
      end if;
      return Get_Nth_Element (Get_Index_Subtype_List (Sub_Type), 0);
   end Get_String_Type_Bound_Type;

   procedure Get_Low_High_Limit (Arange : Iir_Range_Expression;
                                 Low, High : out Iir)
   is
   begin
      case Get_Direction (Arange) is
         when Iir_To =>
            Low := Get_Left_Limit (Arange);
            High := Get_Right_Limit (Arange);
         when Iir_Downto =>
            High := Get_Left_Limit (Arange);
            Low := Get_Right_Limit (Arange);
      end case;
   end Get_Low_High_Limit;

   function Get_Low_Limit (Arange : Iir_Range_Expression) return Iir is
   begin
      case Get_Direction (Arange) is
         when Iir_To =>
            return Get_Left_Limit (Arange);
         when Iir_Downto =>
            return Get_Right_Limit (Arange);
      end case;
   end Get_Low_Limit;

   function Get_High_Limit (Arange : Iir_Range_Expression) return Iir is
   begin
      case Get_Direction (Arange) is
         when Iir_To =>
            return Get_Right_Limit (Arange);
         when Iir_Downto =>
            return Get_Left_Limit (Arange);
      end case;
   end Get_High_Limit;

   function Is_One_Dimensional_Array_Type (A_Type : Iir) return Boolean
   is
      Base_Type : constant Iir := Get_Base_Type (A_Type);
   begin
      if Get_Kind (Base_Type) = Iir_Kind_Array_Type_Definition
        and then Get_Nbr_Elements (Get_Index_Subtype_List (Base_Type)) = 1
      then
         return True;
      else
         return False;
      end if;
   end Is_One_Dimensional_Array_Type;

   function Is_Range_Attribute_Name (Expr : Iir) return Boolean
   is
      Attr : Iir;
      Id : Name_Id;
   begin
      if Get_Kind (Expr) = Iir_Kind_Parenthesis_Name then
         Attr := Get_Prefix (Expr);
      else
         Attr := Expr;
      end if;
      if Get_Kind (Attr) /= Iir_Kind_Attribute_Name then
         return False;
      end if;
      Id := Get_Identifier (Attr);
      return Id = Name_Range or Id = Name_Reverse_Range;
   end Is_Range_Attribute_Name;

   function Create_Array_Subtype (Arr_Type : Iir; Loc : Location_Type)
     return Iir_Array_Subtype_Definition
   is
      Base_Type : constant Iir := Get_Base_Type (Arr_Type);
      El_Type : constant Iir := Get_Element_Subtype (Base_Type);
      Res : Iir_Array_Subtype_Definition;
      List : Iir_Flist;
   begin
      Res := Create_Iir (Iir_Kind_Array_Subtype_Definition);
      Set_Location (Res, Loc);
      Set_Base_Type (Res, Base_Type);
      Set_Element_Subtype (Res, El_Type);
      if Get_Kind (Arr_Type) = Iir_Kind_Array_Subtype_Definition then
         Set_Resolution_Indication (Res, Get_Resolution_Indication (Arr_Type));
      end if;
      Set_Resolved_Flag (Res, Get_Resolved_Flag (Arr_Type));
      Set_Signal_Type_Flag (Res, Get_Signal_Type_Flag (Arr_Type));
      Set_Type_Staticness (Res, Get_Type_Staticness (El_Type));
      List := Create_Iir_Flist (Get_Nbr_Dimensions (Base_Type));
      Set_Index_Subtype_List (Res, List);
      Set_Index_Constraint_List (Res, List);
      return Res;
   end Create_Array_Subtype;

   function Is_Subprogram_Method (Spec : Iir) return Boolean is
   begin
      case Get_Kind (Get_Parent (Spec)) is
         when Iir_Kind_Protected_Type_Declaration
           | Iir_Kind_Protected_Type_Body =>
            return True;
         when others =>
            return False;
      end case;
   end Is_Subprogram_Method;

   function Get_Method_Type (Spec : Iir) return Iir
   is
      Parent : Iir;
   begin
      Parent := Get_Parent (Spec);
      case Get_Kind (Parent) is
         when Iir_Kind_Protected_Type_Declaration =>
            return Parent;
         when Iir_Kind_Protected_Type_Body =>
            return Get_Protected_Type_Declaration (Parent);
         when others =>
            return Null_Iir;
      end case;
   end Get_Method_Type;

   function Get_Actual_Or_Default (Assoc : Iir; Inter : Iir) return Iir is
   begin
      case Get_Kind (Assoc) is
         when Iir_Kind_Association_Element_By_Expression =>
            return Get_Actual (Assoc);
         when Iir_Kind_Association_Element_Open =>
            return Get_Default_Value (Inter);
         when others =>
            Error_Kind ("get_actual_or_default", Assoc);
      end case;
   end Get_Actual_Or_Default;

   function Create_Error (Orig : Iir) return Iir
   is
      Res : Iir;
   begin
      Res := Create_Iir (Iir_Kind_Error);
      if Orig /= Null_Iir then
         Set_Error_Origin (Res, Orig);
         Location_Copy (Res, Orig);
      end if;
      return Res;
   end Create_Error;

   function Create_Error_Expr (Orig : Iir; Atype : Iir) return Iir
   is
      Res : Iir;
   begin
      Res := Create_Error (Orig);
      Set_Expr_Staticness (Res, None);
      Set_Type (Res, Atype);
      return Res;
   end Create_Error_Expr;

   function Create_Error_Type (Orig : Iir) return Iir
   is
      Res : Iir;
   begin
      Res := Create_Error (Orig);
      --Set_Expr_Staticness (Res, Locally);
      Set_Base_Type (Res, Res);
      Set_Type_Declarator (Res, Null_Iir);
      Set_Resolved_Flag (Res, True);
      Set_Signal_Type_Flag (Res, True);
      return Res;
   end Create_Error_Type;

   function Create_Error_Name (Orig : Iir) return Iir
   is
      Res : Iir;
   begin
      Res := Create_Iir (Iir_Kind_Error);
      Set_Expr_Staticness (Res, None);
      Set_Error_Origin (Res, Orig);
      Location_Copy (Res, Orig);
      return Res;
   end Create_Error_Name;

   --  Extract the entity from ASPECT.
   --  Note: if ASPECT is a component declaration, returns ASPECT.
   function Get_Entity_From_Entity_Aspect (Aspect : Iir) return Iir
   is
      Inst : Iir;
   begin
      case Get_Kind (Aspect) is
         when Iir_Kinds_Denoting_Name =>
            --  A component declaration.
            Inst := Get_Named_Entity (Aspect);
            pragma Assert (Get_Kind (Inst) = Iir_Kind_Component_Declaration);
            return Inst;
         when Iir_Kind_Component_Declaration =>
            return Aspect;
         when Iir_Kind_Entity_Aspect_Entity =>
            return Get_Entity (Aspect);
         when Iir_Kind_Entity_Aspect_Configuration =>
            Inst := Get_Configuration (Aspect);
            return Get_Entity (Inst);
         when Iir_Kind_Entity_Aspect_Open =>
            return Null_Iir;
         when others =>
            Error_Kind ("get_entity_from_entity_aspect", Aspect);
      end case;
   end Get_Entity_From_Entity_Aspect;

   function Is_Nested_Package (Pkg : Iir) return Boolean is
   begin
      return Get_Kind (Get_Parent (Pkg)) /= Iir_Kind_Design_Unit;
   end Is_Nested_Package;

   --  LRM08 4.7 Package declarations
   --  If the package header is empty, the package declared by a package
   --  declaration is called a simple package.
   function Is_Simple_Package (Pkg : Iir) return Boolean is
   begin
      return Get_Package_Header (Pkg) = Null_Iir;
   end Is_Simple_Package;

   --  LRM08 4.7 Package declarations
   --  If the package header contains a generic clause and no generic map
   --  aspect, the package is called an uninstantiated package.
   function Is_Uninstantiated_Package (Pkg : Iir) return Boolean
   is
      Header : constant Iir := Get_Package_Header (Pkg);
   begin
      return Header /= Null_Iir
        and then Get_Generic_Map_Aspect_Chain (Header) = Null_Iir;
   end Is_Uninstantiated_Package;

   --  LRM08 4.7 Package declarations
   --  If the package header contains both a generic clause and a generic
   --  map aspect, the package is declared a generic-mapped package.
   function Is_Generic_Mapped_Package (Pkg : Iir) return Boolean
   is
      Header : constant Iir := Get_Package_Header (Pkg);
   begin
      return Header /= Null_Iir
        and then Get_Generic_Map_Aspect_Chain (Header) /= Null_Iir;
   end Is_Generic_Mapped_Package;

   function Kind_In (N : Iir; K1, K2 : Iir_Kind) return Boolean
   is
      K : constant Iir_Kind := Get_Kind (N);
   begin
      return K = K1 or K = K2;
   end Kind_In;

   function Get_HDL_Node (N : PSL_Node) return Iir is
   begin
      return Iir (PSL.Nodes.Get_HDL_Node (N));
   end Get_HDL_Node;

   procedure Set_HDL_Node (N : PSL_Node; Expr : Iir) is
   begin
      PSL.Nodes.Set_HDL_Node (N, PSL.Nodes.HDL_Node (Expr));
   end Set_HDL_Node;
end Vhdl.Utils;