X-Git-Url: https://git.xandkar.net/?p=tiger.ml.git;a=blobdiff_plain;f=compiler%2Fsrc%2Flib%2Ftiger%2Ftiger_semant.ml;h=6bb45fd515a5fb3fe1788417118c5b4b2c144b5a;hp=659bb8542d1469c99150cfda352f73cfdf3a01da;hb=e6e82c0866db4eb08f956b2582e5c2ed5399e986;hpb=523e2b063b9ba20329af61e18dc9a5ccbaca06a0 diff --git a/compiler/src/lib/tiger/tiger_semant.ml b/compiler/src/lib/tiger/tiger_semant.ml index 659bb85..6bb45fd 100644 --- a/compiler/src/lib/tiger/tiger_semant.ml +++ b/compiler/src/lib/tiger/tiger_semant.ml @@ -1,8 +1,11 @@ module List = ListLabels module A = Tiger_absyn +module Dag = Tiger_dag module Env = Tiger_env module E = Tiger_error +module Pos = Tiger_position +module Sym = Tiger_symbol module Translate = Tiger_translate module Type = Tiger_env_type module Value = Tiger_env_value @@ -19,17 +22,35 @@ module Semant : sig * Appel's *) val transExp : env:Env.t -> A.exp -> expty - val transVar : env:Env.t -> A.var -> expty - val transDec : env:Env.t -> A.dec -> Env.t - val transTy : env:Env.t -> A.ty -> Type.t (* needs only type env *) + + (* transVar does not seem to be needed, as trvar handles all our cases. + * Am I wrong? + * + * val transVar : env:Env.t -> A.var -> expty + * + *) end = struct type expty = { exp : Translate.exp ; ty : Type.t } - let unimplemented () = - failwith "unimplemented" + let rec actual_ty ty ~pos = + match ty with + | Type.Name (name, ty_opt_ref) -> + (match !ty_opt_ref with + | None -> + E.raise (E.Unknown_type {ty_id=name; pos}) + | Some ty -> + actual_ty ty ~pos + ) + | Type.Unit + | Type.Nil + | Type.Int + | Type.String + | Type.Record _ + | Type.Array _ -> + ty let return ty = {exp = (); ty} let return_unit = return Type.Unit @@ -42,6 +63,9 @@ end = struct | Some ty -> ty | None -> E.raise (E.Unknown_type {ty_id=sym; pos}) + let env_get_typ_actual ~sym ~env ~pos : Type.t = + actual_ty (env_get_typ ~sym ~env ~pos) ~pos + let env_get_val ~sym ~env ~pos : Value.t = match Env.get_val env sym with | Some ty -> ty @@ -54,7 +78,38 @@ end = struct E.raise (E.Wrong_type {expected=ty_left; given=ty_right; pos}) let check_int expty ~pos : unit = - check_same {exp=(); ty=Type.Int} expty ~pos + check_same return_int expty ~pos + + let paths_of_typedecs typedecs : (Sym.t * Sym.t * Pos.t) list list = + let (path, paths) = + List.fold_left typedecs ~init:([], []) ~f:( + fun (path, paths) (A.TypeDec {name=child; ty; pos}) -> + match ty with + | A.NameTy {symbol=parent; _} -> + (((parent, child, pos) :: path), paths) + | A.RecordTy _ + | A.ArrayTy _ -> + ([], path :: paths) + ) + in + List.map (path :: paths) ~f:List.rev + + let check_cycles (typedecs : A.typedec list) : unit = + let non_empty_paths = + List.filter + (paths_of_typedecs typedecs) + ~f:(function [] -> false | _ -> true) + in + List.iter non_empty_paths ~f:( + fun path -> + match Dag.of_list (List.map path ~f:(fun (p, c, _) -> (p, c))) with + | Ok _ -> + () + | Error `Cycle -> + let (_, from_id, from_pos) = List.hd path in + let (_, to_id, to_pos) = List.hd (List.rev path) in + E.raise (E.Cycle_in_type_decs {from_id; from_pos; to_id; to_pos}) + ) let rec transExp ~env exp = let rec trexp exp = @@ -65,17 +120,58 @@ end = struct return_int | A.StringExp {string=_; _} -> return_string - | A.CallExp {func=_; args=_; pos=_} -> - unimplemented () + | A.CallExp {func; args; pos} -> + (match env_get_val ~sym:func ~env ~pos with + | Value.Fun {formals; result} -> + let expected = List.length formals in + let given = List.length args in + if given = expected then + begin + List.iter2 formals args ~f:(fun ty_expected exp_given -> + check_same + (return (actual_ty ~pos ty_expected)) + (trexp exp_given) + ~pos; + ); + return (actual_ty ~pos result) + end + else + E.raise (E.Wrong_number_of_args {func; expected; given; pos}) + | Value.Var _ -> + E.raise (E.Id_not_a_function {id=func; pos}) + ) | A.OpExp {oper; left; right; pos} -> trop oper ~left ~right ~pos - | A.RecordExp {fields=_; typ=_; pos=_} -> - unimplemented () - | A.SeqExp exps -> - (* Ignoring value because we only care if a type-checking exception - * is raised in one of trexp calls: *) - List.iter exps ~f:(fun (exp, _) -> ignore (trexp exp)); + | A.RecordExp {fields=field_exps; typ; pos} -> + let ty = env_get_typ_actual ~sym:typ ~env ~pos in + Type.if_record + ty + ~f:(fun field_tys -> + List.iter field_exps ~f:(fun (field, exp, pos) -> + (match List.assoc_opt field field_tys with + | Some field_ty -> + check_same (return (actual_ty ~pos field_ty)) (trexp exp) ~pos + | None -> + E.raise + (E.No_such_field_in_record {field; record=ty; pos}) + ) + ) + ) + ~otherwise:(fun () -> + E.raise (E.Wrong_type_used_as_record {ty_id=typ; ty; pos}) + ); + return (actual_ty ~pos ty) + | A.SeqExp [] -> return_unit + | A.SeqExp exps -> + let last xs = + xs + |> List.rev (* Yes, redundant, but clean-looking ;-P *) + |> List.hd (* Empty is matched in above SeqExp match case *) + in + exps + |> List.map ~f:(fun (exp, _) -> trexp exp) + |> last | A.AssignExp {var; exp; pos} -> check_same (trvar var) (trexp exp) ~pos; (* TODO: Add var->exp to val env? *) @@ -102,14 +198,30 @@ end = struct check_int (trexp lo) ~pos; check_int (trexp hi) ~pos; (* Only care if a type-error is raised *) - ignore (transExp ~env:(Env.set_typ env var Type.Int) body); + let env = Env.set_val env var (Value.Var {ty = Type.Int}) in + ignore (transExp ~env body); return_unit | A.BreakExp _ -> return_unit - | A.LetExp {decs=_; body=_; _} -> - unimplemented () - | A.ArrayExp {typ=_; size=_; init=_; _} -> - unimplemented () + | A.LetExp {decs; body; pos=_} -> + (* (1) decs augment env *) + (* (2) body checked against the new env *) + let env = + List.fold_left decs ~init:env ~f:(fun env dec -> transDec dec ~env) + in + transExp body ~env + | A.ArrayExp {typ; size; init; pos} -> + check_int (trexp size) ~pos; + let ty = env_get_typ_actual ~sym:typ ~env ~pos in + Type.if_array + ty + ~f:(fun ty_elements -> + check_same (return (actual_ty ~pos ty_elements)) (trexp init) ~pos + ) + ~otherwise:(fun () -> + E.raise (E.Wrong_type_used_as_array {ty_id=typ; ty; pos}) + ); + return (actual_ty ~pos ty) | A.VarExp var -> trvar var ) @@ -118,7 +230,7 @@ end = struct | A.SimpleVar {symbol=sym; pos} -> (match env_get_val ~sym ~env ~pos with | Value.Fun _ -> E.raise (E.Id_is_a_function {id=sym; pos}) - | Value.Var {ty} -> return ty + | Value.Var {ty} -> return (actual_ty ~pos ty) ) | A.FieldVar {var; symbol; pos} -> let {exp=_; ty} = trvar var in @@ -130,14 +242,20 @@ end = struct E.raise (E.No_such_field_in_record {field=symbol; record=ty; pos}) | Some ty -> - return ty + return (actual_ty ~pos ty) ) ) ~otherwise:(fun () -> E.raise (E.Exp_not_a_record {ty; pos})) - | A.SubscriptVar {var=_; exp=_; pos=_} -> - unimplemented () + | A.SubscriptVar {var; exp; pos} -> + let {exp=_; ty} = trvar var in + check_int (trexp exp) ~pos; + Type.if_array + ty + ~f:(fun ty_elements -> return (actual_ty ~pos ty_elements)) + ~otherwise:(fun () -> E.raise (E.Exp_not_an_array {ty; pos})) ) and trop oper ~left ~right ~pos = + (* TODO: Refactor trop - all opers return bool/int *) let expty_left = trexp left in let expty_right = trexp right in check_same expty_left expty_right ~pos; @@ -159,7 +277,7 @@ end = struct || (T.is_array ty) || (T.is_record ty) then - return ty + return_int (* Because we have no bool type *) else E.raise (E.Invalid_operand_type { oper @@ -175,7 +293,7 @@ end = struct if (T.is_int ty) || (T.is_string ty) then - return ty + return_int (* Because we have no bool type *) else E.raise (E.Invalid_operand_type { oper @@ -186,39 +304,95 @@ end = struct ) in trexp exp - - let transVar ~env:_ var = - (match var with - | A.SimpleVar {symbol=_; _} -> - unimplemented () - | A.FieldVar {var=_; symbol=_; _} -> - unimplemented () - | A.SubscriptVar {var=_; exp=_; _} -> - unimplemented () - ) - - let transDec ~env:_ dec = + and transDec ~(env : Env.t) (dec : A.dec) : Env.t = (match dec with - | A.VarDec {name=_; typ=_; init=_; pos=_; escape=_} -> - unimplemented () - | A.TypeDecs _ -> - unimplemented () - | A.FunDecs _ -> - unimplemented () + | A.VarDec {name; typ=typ_opt; init; pos=pos_outter; escape=_} -> + let ty = + (match (typ_opt, transExp ~env init) with + | None, {ty; exp=()} -> + ty + | Some (sym, pos_inner), expty_init -> + let ty = env_get_typ_actual ~sym ~env ~pos:pos_inner in + check_same (return ty) expty_init ~pos:pos_outter; + ty + ) + in + Env.set_val env name (Value.Var {ty}) + | A.TypeDecs typedecs -> + check_cycles typedecs; + let env = + List.fold_left typedecs ~init:env ~f:( + fun env (A.TypeDec {name; ty=_; pos=_}) -> + Env.set_typ env name (Type.Name (name, ref None)) + ) + in + List.iter typedecs ~f:(fun (A.TypeDec {name; ty=ty_exp; pos}) -> + let ty = transTy ~env ty_exp in + (match env_get_typ ~sym:name ~env ~pos with + | Type.Name (_, ty_opt_ref) -> + ty_opt_ref := Some ty + | Type.Unit + | Type.Nil + | Type.Int + | Type.String + | Type.Record _ + | Type.Array _ -> + () + ) + ); + env + | A.FunDecs fundecs -> + let env_with_fun_heads_only = + List.fold_left fundecs ~init:env ~f:( + fun env (A.FunDec {name; params; result; body=_; pos=_}) -> + let formals = + List.map params ~f:( + fun (A.Field {name=_; typ; pos; escape=_}) -> + env_get_typ_actual ~env ~sym:typ ~pos + ) + in + let result = + match result with + | Some (s, p) -> env_get_typ_actual ~sym:s ~env ~pos:p + | None -> Type.Unit + in + Env.set_val env name (Value.Fun {formals; result}) + ) + in + List.iter fundecs ~f:( + fun (A.FunDec {name=_; params; result=_; body; pos=_}) -> + let env_with_fun_heads_and_local_vars = + List.fold_left params ~init:env_with_fun_heads_only ~f:( + fun env (A.Field {name=var_name; escape=_; typ; pos}) -> + let var_ty = env_get_typ_actual ~env ~sym:typ ~pos in + Env.set_val env var_name (Value.Var {ty = var_ty}) + ) + in + (* we only care if an exception is raised *) + ignore (transExp ~env:env_with_fun_heads_and_local_vars body); + ); + env_with_fun_heads_only ) - - let transTy ~env:_ typ = - (match typ with - | A.NameTy {symbol = _; pos = _} -> - unimplemented () - | A.RecordTy _ -> - unimplemented () - | A.ArrayTy {symbol = _; pos = _} -> - unimplemented () + and transTy ~(env : Env.t) (ty_exp : A.ty) : Type.t = + (match ty_exp with + | A.NameTy {symbol=sym; pos} -> + env_get_typ ~sym ~env ~pos + | A.RecordTy fields -> + let fields = + List.map fields ~f:(fun (A.Field {name; escape=_; typ; pos}) -> + let ty = env_get_typ ~sym:typ ~env ~pos in + (name, ty) + ) + in + Type.new_record fields + | A.ArrayTy {symbol=sym; pos} -> + let element_ty = env_get_typ ~sym ~env ~pos in + Type.new_array element_ty ) end +open Semant + let transProg absyn = - let open Semant in let {exp = _; ty = _} = transExp absyn ~env:Env.base in ()