compiler/src/lib/tiger/tiger_translate.ml

   1 module List = ListLabels
   2
   3 module Frame = Tiger_frame
   4 module Temp  = Tiger_temp
   5
   6 module Level = struct
   7   type t =
   8     { parent  : t option
   9     ; name    : Temp.Label.t
  10     ; formals : bool list
  11     ; frame   : Frame.t
  12     }
  13
  14   let init =
  15     let name    = Temp.Label.gen () in
  16     let formals = [] in
  17     { parent  = None
  18     ; name
  19     ; formals
  20     ; frame   = Frame.make ~name ~formals
  21     }
  22
  23   let next t ~name  ~formals =
  24     (* Adding the extra parameter for the static link. See p. 142 *)
  25     let formals = true :: formals in
  26     { parent = Some t
  27     ; name
  28     ; formals
  29     ; frame = Frame.make ~name ~formals
  30     }
  31
  32   let formals = function {formals; _} ->
  33     formals
  34
  35   let frame = function {frame; _} ->
  36     frame
  37 end
  38
  39 type exp = unit
  40
  41 type access =
  42   (* must know about static links *)
  43   { level        : Level.t
  44   ; frame_access : Frame.access
  45   }
  46
  47 let alloc_local ~level ~escapes =
  48   { level
  49   ; frame_access = Frame.alloc_local (Level.frame level) ~escapes
  50   }
  51
  52 let formals ~level =
  53   (* FIXME: This seems wrong. Should we call Frame.formals? *)
  54   List.map (Level.formals level) ~f:(fun escapes ->
  55     alloc_local ~level ~escapes
  56   )