synth: handle incomplete types

6 files changed, 87 insertions, 24 deletions

diff --git a/src/synth/elab-vhdl_decls.adb b/src/synth/elab-vhdl_decls.adb
index 5d5f38d25..7be65af08 100644
--- a/src/synth/elab-vhdl_decls.adb
+++ b/src/synth/elab-vhdl_decls.adb
@@ -350,7 +350,17 @@ package body Elab.Vhdl_Decls is
          when Iir_Kind_Attribute_Specification =>
             Elab_Attribute_Specification (Syn_Inst, Decl);
          when Iir_Kind_Type_Declaration =>
-            Elab_Type_Definition (Syn_Inst, Get_Type_Definition (Decl));
+            declare
+               Incomp : constant Node :=
+                 Get_Incomplete_Type_Declaration (Decl);
+               Def : constant Node := Get_Type_Definition (Decl);
+            begin
+               Elab_Type_Definition (Syn_Inst, Def);
+               if Incomp /= Null_Node then
+                  Elab_Incomplete_Type_Finish
+                    (Syn_Inst, Get_Type_Definition (Incomp), Def);
+               end if;
+            end;
          when Iir_Kind_Anonymous_Type_Declaration =>
             Elab_Anonymous_Type_Definition
               (Syn_Inst, Get_Type_Definition (Decl),
diff --git a/src/synth/elab-vhdl_objtypes.adb b/src/synth/elab-vhdl_objtypes.adb
index 3662758d6..b027c84f1 100644
--- a/src/synth/elab-vhdl_objtypes.adb
+++ b/src/synth/elab-vhdl_objtypes.adb
@@ -631,7 +631,12 @@ package body Elab.Vhdl_Objtypes is
       function Alloc is new Areapools.Alloc_On_Pool_Addr (Access_Type_Type);
       Bnd_Sz : Size_Type;
    begin
-      Bnd_Sz := Compute_Size_Type (Acc_Type);
+      if Acc_Type = null then
+         --  For incomplete type.
+         Bnd_Sz := 0;
+      else
+         Bnd_Sz := Compute_Size_Type (Acc_Type);
+      end if;
       return To_Type_Acc (Alloc (Current_Pool, (Kind => Type_Access,
                                                 Wkind => Wkind_Sim,
                                                 Al => 2,
@@ -642,6 +647,12 @@ package body Elab.Vhdl_Objtypes is
                                                 Acc_Bnd_Sz => Bnd_Sz)));
    end Create_Access_Type;
 
+   procedure Complete_Access_Type (Acc_Type : Type_Acc; Des_Typ : Type_Acc) is
+   begin
+      Acc_Type.Acc_Acc := Des_Typ;
+      Acc_Type.Acc_Bnd_Sz := Compute_Size_Type (Des_Typ);
+   end Complete_Access_Type;
+
    function Create_File_Type (File_Type : Type_Acc) return Type_Acc
    is
       subtype File_Type_Type is Type_Type (Type_File);
@@ -1039,7 +1050,12 @@ package body Elab.Vhdl_Objtypes is
                                  Typ => Unshare (T.Rec.E (I).Typ, Pool));
             end loop;
          when Type_Access =>
-            Res.Acc_Acc := Unshare (T.Acc_Acc, Pool);
+            if T.Acc_Acc /= null then
+               Res.Acc_Acc := Unshare (T.Acc_Acc, Pool);
+            else
+               --  For incomplete types
+               Res.Acc_Acc := null;
+            end if;
          when Type_File =>
             Res.File_Typ := Unshare (T.File_Typ, Pool);
          when Type_Protected =>
@@ -1122,7 +1138,8 @@ package body Elab.Vhdl_Objtypes is
          when Type_Bit
            | Type_Logic
            | Type_Discrete
-           | Type_Float =>
+           | Type_Float
+           | Type_Access =>
             Res := Typ;
             return;
          when others =>
diff --git a/src/synth/elab-vhdl_objtypes.ads b/src/synth/elab-vhdl_objtypes.ads
index fe1508fbc..3b3547132 100644
--- a/src/synth/elab-vhdl_objtypes.ads
+++ b/src/synth/elab-vhdl_objtypes.ads
@@ -252,7 +252,9 @@ package Elab.Vhdl_Objtypes is
    function Create_Record_Type (Els : Rec_El_Array_Acc) return Type_Acc;
    function Create_Unbounded_Record (Els : Rec_El_Array_Acc) return Type_Acc;
 
+   --  ACC_TYPE can be null for an incomplete type.
    function Create_Access_Type (Acc_Type : Type_Acc) return Type_Acc;
+   procedure Complete_Access_Type (Acc_Type : Type_Acc; Des_Typ : Type_Acc);
 
    function Create_File_Type (File_Type : Type_Acc) return Type_Acc;
 
diff --git a/src/synth/elab-vhdl_types.adb b/src/synth/elab-vhdl_types.adb
index 411b90519..9a8825493 100644
--- a/src/synth/elab-vhdl_types.adb
+++ b/src/synth/elab-vhdl_types.adb
@@ -211,14 +211,6 @@ package body Elab.Vhdl_Types is
       return Res;
    end Create_Bounds_From_Length;
 
-   procedure Synth_Subtype_Indication_If_Anonymous
-     (Syn_Inst : Synth_Instance_Acc; Atype : Node) is
-   begin
-      if Get_Type_Declarator (Atype) = Null_Node then
-         Synth_Subtype_Indication (Syn_Inst, Atype);
-      end if;
-   end Synth_Subtype_Indication_If_Anonymous;
-
    function Synth_Subtype_Indication_If_Anonymous
      (Syn_Inst : Synth_Instance_Acc; Atype : Node) return Type_Acc is
    begin
@@ -310,16 +302,49 @@ package body Elab.Vhdl_Types is
      (Syn_Inst : Synth_Instance_Acc; Def : Node) return Type_Acc
    is
       Des_Type : constant Node := Get_Designated_Type (Def);
+      Des_Ind : constant Node := Get_Designated_Subtype_Indication (Def);
+      T : Node;
       Des_Typ : Type_Acc;
       Typ : Type_Acc;
    begin
-      Synth_Subtype_Indication_If_Anonymous (Syn_Inst, Des_Type);
-      Des_Typ := Get_Subtype_Object (Syn_Inst, Des_Type);
+      if Get_Kind (Des_Ind) in Iir_Kinds_Denoting_Name then
+         T := Get_Named_Entity (Des_Ind);
+         if Get_Kind (T) = Iir_Kind_Type_Declaration
+           and then
+           Get_Kind (Get_Type (T)) = Iir_Kind_Incomplete_Type_Definition
+         then
+            --  Access to incomplete type.
+            Des_Typ := null;
+         else
+            Des_Typ := Get_Subtype_Object (Syn_Inst, Des_Type);
+         end if;
+      else
+         Des_Typ := Synth_Subtype_Indication_If_Anonymous (Syn_Inst, Des_Type);
+      end if;
 
       Typ := Create_Access_Type (Des_Typ);
       return Typ;
    end Synth_Access_Type_Definition;
 
+   procedure Elab_Incomplete_Type_Finish (Syn_Inst : Synth_Instance_Acc;
+                                          Incomp : Node;
+                                          Des_Def : Node)
+   is
+      Des_Typ : Type_Acc;
+      Acc : Node;
+      Acc_Typ : Type_Acc;
+   begin
+      Des_Typ := Get_Subtype_Object (Syn_Inst, Des_Def);
+
+      --  Complete all the access types in the chain.
+      Acc := Get_Incomplete_Type_Ref_Chain (Incomp);
+      while Acc /= Null_Node loop
+         Acc_Typ := Get_Subtype_Object (Syn_Inst, Acc);
+         Complete_Access_Type (Acc_Typ, Des_Typ);
+         Acc := Get_Incomplete_Type_Ref_Chain (Acc);
+      end loop;
+   end Elab_Incomplete_Type_Finish;
+
    function Synth_File_Type_Definition
      (Syn_Inst : Synth_Instance_Acc; Def : Node) return Type_Acc
    is
@@ -415,6 +440,8 @@ package body Elab.Vhdl_Types is
             --  TODO...
             Elab.Vhdl_Decls.Elab_Declarations
               (Syn_Inst, Get_Declaration_Chain (Def));
+         when Iir_Kind_Incomplete_Type_Definition =>
+            return;
          when others =>
             Vhdl.Errors.Error_Kind ("synth_type_definition", Def);
       end case;
diff --git a/src/synth/elab-vhdl_types.ads b/src/synth/elab-vhdl_types.ads
index 5f8bbab0e..30591e8da 100644
--- a/src/synth/elab-vhdl_types.ads
+++ b/src/synth/elab-vhdl_types.ads
@@ -64,6 +64,12 @@ package Elab.Vhdl_Types is
    procedure Elab_Anonymous_Type_Definition
      (Syn_Inst : Synth_Instance_Acc; Def : Node; St : Node);
 
+   --  Complete incomplete type definition INCOMP.
+   --  DES_DEF is the complete designated type.
+   procedure Elab_Incomplete_Type_Finish (Syn_Inst : Synth_Instance_Acc;
+                                          Incomp : Node;
+                                          Des_Def : Node);
+
    --  Exported only for Vhdl.Evaluation to create temporary types.
    function Elab_Enumeration_Type_Definition (Def : Node) return Type_Acc;
    function Elab_Scalar_Type_Definition (Def : Node; St : Node)
diff --git a/src/synth/synth-vhdl_stmts.adb b/src/synth/synth-vhdl_stmts.adb
index 199bd86d6..36c8cb6cb 100644
--- a/src/synth/synth-vhdl_stmts.adb
+++ b/src/synth/synth-vhdl_stmts.adb
@@ -258,16 +258,17 @@ package body Synth.Vhdl_Stmts is
 
          when Iir_Kind_Implicit_Dereference
            | Iir_Kind_Dereference =>
-            Synth_Assignment_Prefix
-              (Syn_Inst, Get_Prefix (Pfx), Dest_Base, Dest_Typ, Dest_Off);
-            if Dest_Off /= (0, 0) then
-               raise Internal_Error;
-            end if;
-            Dest_Base := Create_Value_Memtyp
-              (Elab.Vhdl_Heap.Synth_Dereference (Read_Access (Dest_Base)));
-            Dest_Typ := Dest_Base.Typ;
-            Dest_Dyn := No_Dyn_Name;
-
+            declare
+               Acc : Memtyp;
+            begin
+               Synth_Assignment_Prefix
+                 (Syn_Inst, Get_Prefix (Pfx), Dest_Base, Dest_Typ, Dest_Off);
+               Acc := (Dest_Typ, Dest_Base.Val.Mem + Dest_Off.Mem_Off);
+               Dest_Base := Create_Value_Memtyp
+                 (Elab.Vhdl_Heap.Synth_Dereference (Read_Access (Acc)));
+               Dest_Typ := Dest_Base.Typ;
+               Dest_Dyn := No_Dyn_Name;
+            end;
          when others =>
             Error_Kind ("synth_assignment_prefix", Pfx);
       end case;