path: root/src/synth/synth-objtypes.ads

--  Values in synthesis.
--  Copyright (C) 2017 Tristan Gingold
--
--  This file is part of GHDL.
--
--  This program 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 of the License, or
--  (at your option) any later version.
--
--  This program 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 this program; if not, write to the Free Software
--  Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
--  MA 02110-1301, USA.

with Types; use Types;
with Areapools; use Areapools;

with Netlists; use Netlists;

with Vhdl.Nodes; use Vhdl.Nodes;

package Synth.Objtypes is
   type Discrete_Range_Type is record
      --  An integer range.
      Dir : Iir_Direction;

      --  Netlist representation: signed or unsigned, width of vector.
      Is_Signed : Boolean;

      Left : Int64;
      Right : Int64;
   end record;

   --  Return the width of RNG.
   function Discrete_Range_Width (Rng : Discrete_Range_Type) return Width;

   type Float_Range_Type is record
      Dir : Iir_Direction;
      Left : Fp64;
      Right : Fp64;
   end record;

   type Bound_Type is record
      Dir : Iir_Direction;
      Left : Int32;
      Right : Int32;
      Len : Width;
   end record;

   type Bound_Array_Type is array (Dim_Type range <>) of Bound_Type;

   type Bound_Array (Ndim : Dim_Type) is record
      D : Bound_Array_Type (1 .. Ndim);
   end record;

   type Bound_Array_Acc is access Bound_Array;

   type Type_Kind is
     (
      Type_Bit,
      Type_Logic,
      Type_Discrete,
      Type_Float,
      Type_Vector,
      Type_Unbounded_Vector,

      --  A slice is for a slice of vector with dynamic bounds.  So the bounds
      --  of the result aren't known, but its width is.
      Type_Slice,
      Type_Array,
      Type_Unbounded_Array,
      Type_Record,

      Type_Access,
      Type_File
     );

   subtype Type_Nets is Type_Kind range Type_Bit .. Type_Logic;

   type Type_Type (Kind : Type_Kind);
   type Type_Acc is access Type_Type;

   type Rec_El_Type is record
      --  Bit offset: offset of the element in a net.
      Boff : Uns32;

      --  Memory offset: offset of the element in memory.
      Moff : Size_Type;

      --  Type of the element.
      Typ : Type_Acc;
   end record;

   type Rec_El_Array_Type is array (Iir_Index32 range <>) of Rec_El_Type;
   type Rec_El_Array (Len : Iir_Index32) is record
      E : Rec_El_Array_Type (1 .. Len);
   end record;

   type Rec_El_Array_Acc is access Rec_El_Array;

   --  Power of 2 alignment.
   type Palign_Type is range 0 .. 3;

   type Type_Type (Kind : Type_Kind) is record
      --  False if the type is not synthesisable: is or contains access/file.
      Is_Synth : Boolean;

      --  Alignment (in bytes) for this type.
      Al : Palign_Type;

      --  Number of bytes (when in memory) for this type.
      Sz : Size_Type;

      --  Number of bits (when in a net) for this type.
      W : Width;

      case Kind is
         when Type_Bit
           | Type_Logic =>
            null;
         when Type_Discrete =>
            Drange : Discrete_Range_Type;
         when Type_Float =>
            Frange : Float_Range_Type;
         when Type_Vector =>
            Vbound : Bound_Type;
            Vec_El : Type_Acc;
         when Type_Unbounded_Vector =>
            Uvec_El : Type_Acc;
         when Type_Slice =>
            Slice_El : Type_Acc;
         when Type_Array =>
            Abounds : Bound_Array_Acc;
            Arr_El : Type_Acc;
         when Type_Unbounded_Array =>
            Uarr_Ndim : Dim_Type;
            Uarr_El : Type_Acc;
         when Type_Record =>
            Rec : Rec_El_Array_Acc;
         when Type_Access =>
            Acc_Acc : Type_Acc;
         when Type_File =>
            File_Typ : Type_Acc;
      end case;
   end record;

   type Memory_Element is mod 2**8;
   type Memory_Array is array (Size_Type range <>) of Memory_Element;

   --  Flat pointer for a generic pointer.
   type Memory_Ptr is access all Memory_Array (Size_Type);

   type Memtyp is record
      Typ : Type_Acc;
      Mem : Memory_Ptr;
   end record;

   --  Offsets for a value.
   type Value_Offsets is record
      Net_Off : Uns32;
      Mem_Off : Size_Type;
   end record;

   function "+" (L, R : Value_Offsets) return Value_Offsets;

   Global_Pool : aliased Areapool;
   Expr_Pool : aliased Areapool;

   --  Areapool used by Create_*_Value
   Current_Pool : Areapool_Acc := Expr_Pool'Access;

   --  Pool for objects allocated in the current instance.
   Instance_Pool : Areapool_Acc;

   --  Types.
   function Create_Discrete_Type (Rng : Discrete_Range_Type;
                                  Sz : Size_Type;
                                  W : Width)
                                 return Type_Acc;

   function Create_Float_Type (Rng : Float_Range_Type) return Type_Acc;
   function Create_Vec_Type_By_Length (Len : Width; El : Type_Acc)
                                      return Type_Acc;
   function Create_Vector_Type (Bnd : Bound_Type; El_Type : Type_Acc)
                               return Type_Acc;
   function Create_Unbounded_Vector (El_Type : Type_Acc) return Type_Acc;
   function Create_Slice_Type (Len : Uns32; El_Type : Type_Acc)
                              return Type_Acc;
   function Create_Bound_Array (Ndims : Dim_Type) return Bound_Array_Acc;
   function Create_Array_Type (Bnd : Bound_Array_Acc; El_Type : Type_Acc)
                              return Type_Acc;
   function Create_Unbounded_Array (Ndim : Dim_Type; El_Type : Type_Acc)
                                   return Type_Acc;
   function Create_Rec_El_Array (Nels : Iir_Index32) return Rec_El_Array_Acc;

   function Create_Record_Type (Els : Rec_El_Array_Acc) return Type_Acc;

   function Create_Access_Type (Acc_Type : Type_Acc) return Type_Acc;

   function Create_File_Type (File_Type : Type_Acc) return Type_Acc;

   --  Return the bounds of dimension DIM of a vector/array.  For a vector,
   --  DIM must be 1.
   function Get_Array_Bound (Typ : Type_Acc; Dim : Dim_Type)
                            return Bound_Type;

   --  Return the length of RNG.
   function Get_Range_Length (Rng : Discrete_Range_Type) return Uns32;

   --  Return the element of a vector/array/unbounded_array.
   function Get_Array_Element (Arr_Type : Type_Acc) return Type_Acc;

   function Is_Bounded_Type (Typ : Type_Acc) return Boolean;

   function Are_Types_Equal (L, R : Type_Acc) return Boolean;

   --  Return the length of a vector type.
   function Vec_Length (Typ : Type_Acc) return Iir_Index32;

   --  Get the number of indexes in array type TYP without counting
   --  sub-elements.
   function Get_Array_Flat_Length (Typ : Type_Acc) return Iir_Index32;

   --  Return length of dimension DIM of type T.
   function Get_Bound_Length (T : Type_Acc; Dim : Dim_Type) return Width;

   function Is_Matching_Bounds (L, R : Type_Acc) return Boolean;

   function Get_Type_Width (Atype : Type_Acc) return Width;

   procedure Init;

   --  Set by Init.
   Boolean_Type : Type_Acc := null;
   Logic_Type : Type_Acc := null;
   Bit_Type : Type_Acc := null;
end Synth.Objtypes;