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open Abstract_syntax_tree
open Environment_domain
open Util
module Make (E : ENVIRONMENT_DOMAIN) = struct
let neg (e, l) =
(AST_unary(AST_NOT, (e, l))), l
let rec condition cond env =
begin match fst cond with
| AST_binary (AST_LESS_EQUAL, e1, e2) ->
E.compare env e1 e2
| AST_binary (AST_GREATER_EQUAL, e1, e2) ->
E.compare env e2 e1
| AST_binary (AST_AND, e1, e2) ->
E.meet (condition e1 env) (condition e2 env)
| AST_binary (AST_OR, e1, e2) ->
E.join (condition e1 env) (condition e2 env)
| _ -> env (* TODO : encode some transformations *)
end
let rec interp_stmt env stat =
begin match fst stat with
| AST_block b ->
List.fold_left interp_stmt env b
| AST_assign ((id, _), exp) ->
E.assign env id exp
| AST_if (cond, tb, None) ->
E.join
(interp_stmt (condition cond env) tb)
(condition (neg cond) env)
| AST_if (cond, tb, Some eb) ->
E.join
(interp_stmt (condition cond env) tb)
(interp_stmt (condition (neg cond) env) eb)
| AST_while (cond, (body, _)) ->
(* TODO *)
env
| AST_HALT -> E.bottom
| AST_assert (cond, l) ->
(* TODO *)
env
| AST_print items ->
(* TODO *)
env
| _ -> assert false (* not implemented *)
end
let interpret prog =
List.fold_left
(fun env x -> match x with
| AST_stat st -> interp_stmt env st
| _ -> env)
E.init
(fst prog)
end
|
