CristalCaveGem » LustreC

(********************************************************************)

(*                                                                  *)

(*  The LustreC compiler toolset   /  The LustreC Development Team  *)

(*  Copyright 2012 -    --   ONERA - CNRS - INPT - LIFL             *)

(*                                                                  *)

(*  LustreC is free software, distributed WITHOUT ANY WARRANTY      *)

(*  under the terms of the GNU Lesser General Public License        *)

(*  version 2.1.                                                    *)

(*                                                                  *) 

(*  This file was originally from the Prelude compiler              *)

(*                                                                  *) 

(********************************************************************)

(** Types definitions and a few utility functions on types. *)

open Utils

open Dimension

type type_expr =

    {mutable tdesc: type_desc;

     tid: int}

and type_desc =

  | Tconst of ident (* type constant *)

  | Tint

  | Treal

  | Tbool

  | Trat (* Actually unused for now. Only place where it can appear is

            in a clock declaration *)

  | Tclock of type_expr (* A type expression explicitely tagged as carrying a clock *)

  | Tarrow of type_expr * type_expr

  | Ttuple of type_expr list

  | Tenum of ident list

  | Tstruct of (ident * type_expr) list

  | Tarray of dim_expr * type_expr

  | Tstatic of dim_expr * type_expr (* a type carried by a dimension expression *)

  | Tlink of type_expr (* During unification, make links instead of substitutions *)

  | Tvar (* Monomorphic type variable *)

  | Tunivar (* Polymorphic type variable *)

type error =

    Unbound_value of ident  

  | Already_bound of ident

  | Already_defined of ident

  | Undefined_var of ISet.t

  | Declared_but_undefined of ident

  | Unbound_type of ident

  | Not_a_dimension

  | Not_a_constant

  | Assigned_constant of ident

  | WrongArity of int * int

  | WrongMorphism of int * int

  | Type_mismatch of ident

  | Type_clash of type_expr * type_expr

  | Poly_imported_node of ident

exception Unify of type_expr * type_expr

exception Error of Location.t * error

(* Pretty-print*)

open Format

let rec print_struct_ty_field fmt (label, ty) =

  fprintf fmt "%a : %a" pp_print_string label print_ty ty

and print_ty fmt ty =

  match ty.tdesc with

  | Tvar ->

    fprintf fmt "_%s" (name_of_type ty.tid)

  | Tint ->

    fprintf fmt "int"

  | Treal ->

    fprintf fmt "real"

  | Tbool ->

    fprintf fmt "bool"

  | Tclock t ->

    fprintf fmt "%a clock" print_ty t

  | Tstatic (d, t) ->

    fprintf fmt "(%a:%a)" Dimension.pp_dimension d print_ty t

  | Tconst t ->

    fprintf fmt "%s" t

  | Trat ->

    fprintf fmt "rat"

  | Tarrow (ty1,ty2) ->

    fprintf fmt "%a -> %a" print_ty ty1 print_ty ty2

  | Ttuple tylist ->

    fprintf fmt "(%a)"

      (Utils.fprintf_list ~sep:" * " print_ty) tylist

  | Tenum taglist ->

    fprintf fmt "enum {%a }"

      (Utils.fprintf_list ~sep:", " pp_print_string) taglist

  | Tstruct fieldlist ->

    fprintf fmt "struct {%a }"

      (Utils.fprintf_list ~sep:"; " print_struct_ty_field) fieldlist

  | Tarray (e, ty) ->

    fprintf fmt "%a^%a" print_ty ty Dimension.pp_dimension e

  | Tlink ty ->

      print_ty fmt ty

  | Tunivar ->

    fprintf fmt "'%s" (name_of_type ty.tid)

let rec print_node_struct_ty_field fmt (label, ty) =

  fprintf fmt "%a : %a" pp_print_string label print_node_ty ty

and print_node_ty fmt ty =

  match ty.tdesc with

  | Tvar -> begin

(*Format.eprintf "DEBUG:Types.print_node@.";*)

    fprintf fmt "_%s" (name_of_type ty.tid)

end

  | Tint ->

    fprintf fmt "int"

  | Treal ->

    fprintf fmt "real"

  | Tbool ->

    fprintf fmt "bool"

  | Tclock t ->

    fprintf fmt "%a clock" print_node_ty t

  | Tstatic (_, t) ->

    fprintf fmt "%a" print_node_ty t

  | Tconst t ->

    fprintf fmt "%s" t

  | Trat ->

    fprintf fmt "rat"

  | Tarrow (ty1,ty2) ->

    fprintf fmt "%a -> %a" print_node_ty ty1 print_node_ty ty2

  | Ttuple tylist ->

    fprintf fmt "(%a)"

      (Utils.fprintf_list ~sep:"*" print_node_ty) tylist

  | Tenum taglist ->

    fprintf fmt "enum {%a }"

      (Utils.fprintf_list ~sep:", " pp_print_string) taglist

  | Tstruct fieldlist ->

    fprintf fmt "struct {%a }"

      (Utils.fprintf_list ~sep:"; " print_node_struct_ty_field) fieldlist

  | Tarray (e, ty) ->

    fprintf fmt "%a^%a" print_node_ty ty Dimension.pp_dimension e

  | Tlink ty ->

      print_node_ty fmt ty

  | Tunivar ->

    fprintf fmt "'%s" (name_of_type ty.tid)

let pp_error fmt = function

  | Unbound_value id ->

    fprintf fmt "Unknown value %s@." id

  | Unbound_type id ->

    fprintf fmt "Unknown type %s@." id

  | Already_bound id ->

    fprintf fmt "%s is already declared@." id

  | Already_defined id ->

    fprintf fmt "Multiple definitions of variable %s@." id

  | Not_a_constant ->

    fprintf fmt "This expression is not a constant@."

  | Assigned_constant id ->

    fprintf fmt "The constant %s cannot be assigned@." id

  | Not_a_dimension ->

    fprintf fmt "This expression is not a valid dimension@."

  | WrongArity (ar1, ar2) ->

    fprintf fmt "Expecting %d argument(s), found %d@." ar1 ar2

  | WrongMorphism (ar1, ar2) ->

    fprintf fmt "Expecting %d argument(s) for homomorphic extension, found %d@." ar1 ar2

  | Type_mismatch id ->

    fprintf fmt "Definition and declaration of type %s don't agree@." id

  | Undefined_var vset ->

    fprintf fmt "No definition provided for variable(s): %a@."

      (Utils.fprintf_list ~sep:"," pp_print_string)

      (ISet.elements vset)

  | Declared_but_undefined id ->

     fprintf fmt "%s is declared but not defined@." id

  | Type_clash (ty1,ty2) ->

      Utils.reset_names ();

    fprintf fmt "Expected type %a, got type %a@." print_ty ty1 print_ty ty2

  | Poly_imported_node id ->

    fprintf fmt "Imported nodes cannot have a polymorphic type@."

let new_id = ref (-1)

let new_ty desc =

  incr new_id; {tdesc = desc; tid = !new_id }

let new_var () =

  new_ty Tvar

let new_univar () =

  new_ty Tunivar

let rec repr =

  function

    {tdesc = Tlink t'} ->

      repr t'

  | t -> t

let get_static_value ty =

  match (repr ty).tdesc with

  | Tstatic (d, _) -> Some d

  | _              -> None

let get_field_type ty label =

  match (repr ty).tdesc with

  | Tstruct fl -> (try Some (List.assoc label fl) with Not_found -> None)

  | _          -> None

let is_numeric_type ty =

 match (repr ty).tdesc with

 | Tint

 | Treal -> true

 | _     -> false

let is_bool_type ty =

 match (repr ty).tdesc with

 | Tbool -> true

 | _     -> false

let get_clock_base_type ty =

 match (repr ty).tdesc with

 | Tclock ty -> Some ty

 | _         -> None

let unclock_type ty =

  let ty = repr ty in

  match ty.tdesc with

  | Tclock ty' -> ty'

  | _          -> ty

let rec is_dimension_type ty =

 match (repr ty).tdesc with

 | Tint

 | Tbool -> true

 | Tclock ty'

 | Tstatic (_, ty') -> is_dimension_type ty'

 | _                -> false

let dynamic_type ty =

  let ty = repr ty in

  match ty.tdesc with

  | Tstatic (_, ty') -> ty'

  | _                -> ty

let is_tuple_type ty =

 match (repr ty).tdesc with

 | Ttuple _         -> true

 | _                -> false

let map_tuple_type f ty =

  let ty = dynamic_type ty in

  match ty.tdesc with

  | (Ttuple ty_list) -> { ty with tdesc = Ttuple (List.map f ty_list) }

  | _                -> f ty

let rec is_struct_type ty =

 match (repr ty).tdesc with

 | Tstruct _        -> true

 | Tstatic (_, ty') -> is_struct_type ty'

 | _                -> false

let rec is_array_type ty =

 match (repr ty).tdesc with

 | Tarray _         -> true

 | Tstatic (_, ty') -> is_array_type ty' (* looks strange !? *)

 | _                -> false

let array_type_dimension ty =

  match (dynamic_type ty).tdesc with

  | Tarray (d, _) -> d

  | _             -> (Format.eprintf "internal error: Types.array_type_dimension %a@." print_ty ty; assert false)

let rec array_type_multi_dimension ty =

  match (dynamic_type ty).tdesc with

  | Tarray (d, ty') -> d :: array_type_multi_dimension ty'

  | _               -> []

let array_element_type ty =

  match (dynamic_type ty).tdesc with

  | Tarray (_, ty') -> ty'

  | _               -> (Format.eprintf "internal error: Types.array_element_type %a@." print_ty ty; assert false)

let rec array_base_type ty =

  let ty = repr ty in

  match ty.tdesc with

  | Tarray (_, ty')

  | Tstatic (_, ty') -> array_base_type ty'

  | _                -> ty

let is_address_type ty =

  is_array_type ty || is_struct_type ty

let rec is_generic_type ty =

 match (dynamic_type ty).tdesc with

  | Tarray (d, ty') ->

    (not (Dimension.is_dimension_const d)) || (is_generic_type ty')

  | _               -> false

(** Splits [ty] into the [lhs,rhs] of an arrow type. Expects an arrow type

    (ensured by language syntax) *)

let rec split_arrow ty =

  match (repr ty).tdesc with

  | Tarrow (tin,tout) -> tin,tout

  | Tstatic (_, ty')  -> split_arrow ty'

    (* Functions are not first order, I don't think the var case

       needs to be considered here *)

  | _ -> Format.eprintf "type %a is not a map@.Unable to split@.@?" print_ty ty; assert false

(** Returns the type corresponding to a type list. *)

let type_of_type_list tyl =

  if (List.length tyl) > 1 then

    new_ty (Ttuple tyl)

  else

    List.hd tyl

let type_list_of_type ty =

 match (repr ty).tdesc with

 | Ttuple tl -> tl

 | _         -> [ty]

(** [is_polymorphic ty] returns true if [ty] is polymorphic. *)

let rec is_polymorphic ty =

  match ty.tdesc with

  | Tenum _ | Tvar | Tint | Treal | Tbool | Trat | Tconst _ -> false

  | Tclock ty -> is_polymorphic ty

  | Tarrow (ty1,ty2) -> (is_polymorphic ty1) || (is_polymorphic ty2)

  | Ttuple tl -> List.exists (fun t -> is_polymorphic t) tl

  | Tstruct fl -> List.exists (fun (_, t) -> is_polymorphic t) fl

  | Tlink t' -> is_polymorphic t'

  | Tarray (d, ty)

  | Tstatic (d, ty) -> Dimension.is_polymorphic d || is_polymorphic ty

  | Tunivar -> true

let mktyptuple nb typ =

  let array = Array.make nb typ in

  Ttuple (Array.to_list array)

(* Local Variables: *)

(* compile-command:"make -C .." *)

(* End: *)