diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/rewrites.ml | 236 |
1 files changed, 236 insertions, 0 deletions
diff --git a/src/rewrites.ml b/src/rewrites.ml index 49409d1b..cfb09890 100644 --- a/src/rewrites.ml +++ b/src/rewrites.ml @@ -3064,6 +3064,237 @@ let construct_bool_match env (match_on : tannot exp) (pexp : tannot pexp) : tann let false_pexp = Pat_aux (Pat_exp (annot_pat P_wild unk env (typ_of match_on), false_exp), unkt) in annot_exp (E_case (match_on, [true_pexp; false_pexp])) unk env bool_typ +let rec bindings_of_pat (P_aux (p_aux, p_annot) as pat) = + match p_aux with + | P_lit _ | P_wild -> [] + | P_id id -> [pat] + | P_record _ -> failwith "record patterns not yet implemented" + (* we assume the type-checker has already checked the two sides have the same bindings *) + | P_or (left, right) -> bindings_of_pat left + | P_as (p, id) -> [annot_pat (P_id id) unk (pat_env_of p) (pat_typ_of p)] + | P_cons (left, right) -> bindings_of_pat left @ bindings_of_pat right + (* todo: is this right for negated patterns? *) + | P_not p + | P_typ (_, p) + | P_var (p, _) -> bindings_of_pat p + | P_app (_, ps) + | P_vector ps + | P_vector_concat ps + | P_tup ps + | P_list ps + | P_string_append ps -> List.map bindings_of_pat ps |> List.flatten + +let rec binding_typs_of_pat (P_aux (p_aux, p_annot) as pat) = + match p_aux with + | P_lit _ | P_wild -> [] + | P_id id -> [pat_typ_of pat] + | P_record _ -> failwith "record patterns not yet implemented" + (* we assume the type-checker has already checked the two sides have the same bindings *) + | P_or (left, right) -> binding_typs_of_pat left + | P_as (p, id) -> [pat_typ_of p] + | P_cons (left, right) -> binding_typs_of_pat left @ binding_typs_of_pat right + (* todo: is this right for negated patterns? *) + | P_not p + | P_typ (_, p) + | P_var (p, _) -> binding_typs_of_pat p + | P_app (_, ps) + | P_vector ps + | P_vector_concat ps + | P_tup ps + | P_list ps + | P_string_append ps -> List.map binding_typs_of_pat ps |> List.flatten + +let construct_toplevel_string_append_call env f_id bindings binding_typs guard expr = + (* s# if match f#(s#) { Some (bindings) => guard, _ => false) } => let Some(bindings) = f#(s#) in expr *) + let s_id = fresh_stringappend_id () in + let option_typ = app_typ (mk_id "option") [Typ_arg_aux (Typ_arg_typ (match binding_typs with + | [] -> unit_typ + | [typ] -> typ + | typs -> tuple_typ typs + ), unk)] + in + let bindings = if bindings = [] then + [annot_pat (P_lit (mk_lit L_unit)) unk env unit_typ] + else + bindings + in + let new_pat = annot_pat (P_id s_id) unk env string_typ in + let new_guard = annot_exp ( + E_case (annot_exp (E_app (f_id, [annot_exp (E_id s_id) unk env string_typ])) unk env option_typ, + [ + Pat_aux (Pat_exp (annot_pat (P_app (mk_id "Some", bindings)) unk env option_typ, guard), unkt); + Pat_aux (Pat_exp (annot_pat P_wild unk env option_typ, annot_exp (E_lit (mk_lit L_false)) unk env bool_typ), unkt) + ] + ) + ) unk env bool_typ in + let new_letbind = annot_letbind (P_app (mk_id "Some", bindings), annot_exp (E_app (f_id, [annot_exp (E_id s_id) unk env string_typ])) unk env option_typ) unk env option_typ in + let new_expr = annot_exp (E_let (new_letbind, expr)) unk env (typ_of expr) in + (new_pat, [new_guard], new_expr) + +let construct_toplevel_string_append_func env f_id pat = + let binding_typs = binding_typs_of_pat pat in + let bindings = bindings_of_pat pat in + let bindings = if bindings = [] then + [annot_pat (P_lit (mk_lit L_unit)) unk env unit_typ] + else + bindings + in + let option_typ = app_typ (mk_id "option") [Typ_arg_aux (Typ_arg_typ (match binding_typs with + | [] -> unit_typ + | [typ] -> typ + | typs -> tuple_typ typs + ), unk)] + in + let fun_typ = (mk_typ (Typ_fn (string_typ, option_typ, no_effect))) in + let new_val_spec = VS_aux (VS_val_spec (mk_typschm (TypQ_aux (TypQ_no_forall, unk)) fun_typ, f_id, (fun _ -> None), false), unkt) in + let new_val_spec, env = Type_check.check_val_spec env new_val_spec in + let non_rec = (Rec_aux (Rec_nonrec, Parse_ast.Unknown)) in + let no_tannot = (Typ_annot_opt_aux (Typ_annot_opt_none, Parse_ast.Unknown)) in + let effect_pure = (Effect_opt_aux (Effect_opt_pure, Parse_ast.Unknown)) in + let s_id = fresh_stringappend_id () in + let arg_pat = mk_pat (P_id s_id) in + (* We can ignore guards here because we've already removed them *) + let rec rewrite_pat env (pat, guards, expr) = + match pat with + (* "lit" ^ pat2 ^ ... ^ patn => Some(...) ---> s# if startswith(s#, "lit") => match string_drop(s#, strlen("lit")) { + pat2 => Some(...) + _ => None() + } + *) + | P_aux (P_string_append ( + P_aux (P_lit (L_aux (L_string s, _) as lit), _) + :: pats + ), psa_annot) -> + let s_id = fresh_stringappend_id () in + let drop_exp = annot_exp (E_app (mk_id "string_drop", [annot_exp (E_id s_id) unk env string_typ; annot_exp (E_app (mk_id "string_length", [annot_exp (E_lit lit) unk env string_typ])) unk env nat_typ])) unk env string_typ in + (* recurse into pat2 .. patn *) + let new_pat2_pexp = + match rewrite_pat env (P_aux (P_string_append pats, psa_annot), guards, expr) with + | pat, [], expr -> Pat_aux (Pat_exp (pat, expr), unkt) + | pat, gs, expr -> Pat_aux (Pat_when (pat, fold_typed_guards env gs, expr), unkt) + in + let new_guard = annot_exp (E_app (mk_id "string_startswith", [annot_exp (E_id s_id) unk env string_typ; + annot_exp (E_lit lit) unk env string_typ] + )) unk env bool_typ in + let new_wildcard = Pat_aux (Pat_exp (annot_pat P_wild unk env string_typ, annot_exp (E_app (mk_id "None", [annot_exp (E_lit (mk_lit L_unit)) unk env unit_typ])) unk env option_typ), unkt) in + let new_expr = annot_exp (E_case (drop_exp, [new_pat2_pexp; new_wildcard])) unk env (typ_of expr) in + (annot_pat (P_id s_id) unk env string_typ, [new_guard], new_expr) + (* mapping(x) ^ pat2 ^ .. ^ patn => Some(...) ---> s# => match map_matches_prefix(s#) { + Some(x, n#) => match string_drop(s#, n#) { + pat2 ^ .. ^ patn => Some(...) + _ => None() + } + } + *) + | P_aux (P_string_append ( + P_aux (P_app (mapping_id, arg_pats) , _) + :: pats + ), psa_annot) + when Env.is_mapping mapping_id env -> + (* common things *) + let mapping_prefix_func = + match mapping_id with + | Id_aux (Id id, _) + | Id_aux (DeIid id, _) -> id ^ "_matches_prefix" + in + let mapping_inner_typ = + match Env.get_val_spec (mk_id mapping_prefix_func) env with + | (_, Typ_aux (Typ_fn (_, Typ_aux (Typ_app (_, [Typ_arg_aux (Typ_arg_typ typ, _)]), _), _), _)) -> typ + | _ -> typ_error Parse_ast.Unknown "mapping prefix func without correct function type?" + in + + let s_id = fresh_stringappend_id () in + let len_id = fresh_stringappend_id () in + + (* construct drop expression -- string_drop(s#, len#) *) + let drop_exp = annot_exp (E_app (mk_id "string_drop", + [annot_exp (E_id s_id) unk env string_typ; + annot_exp (E_id len_id) unk env nat_typ])) + unk env string_typ in + (* construct func expression -- maybe_atoi s# *) + let func_exp = annot_exp (E_app (mk_id mapping_prefix_func, + [annot_exp (E_id s_id) unk env string_typ])) + unk env mapping_inner_typ in + (* construct some pattern -- Some (n#, len#) *) + let opt_typ = app_typ (mk_id "option") [Typ_arg_aux (Typ_arg_typ mapping_inner_typ, unk)] in + let tup_arg_pat = match arg_pats with + | [] -> assert false + | [arg_pat] -> arg_pat + | arg_pats -> annot_pat (P_tup arg_pats) unk env (tuple_typ (List.map pat_typ_of arg_pats)) + in + + let some_pat = annot_pat (P_app (mk_id "Some", + [tup_arg_pat; + annot_pat (P_id len_id) unk env nat_typ])) + unk env opt_typ in + let some_pat, some_pat_env, _ = bind_pat env (strip_pat some_pat) opt_typ in + + (* need to add the Some(...) env to tup_arg_pats for pat_to_exp below as it calls the typechecker *) + let tup_arg_pat = map_pat_annot (fun (l, tannot) -> (l, replace_env some_pat_env tannot)) tup_arg_pat in + + let new_wildcard = Pat_aux (Pat_exp (annot_pat P_wild unk env string_typ, annot_exp (E_app (mk_id "None", [annot_exp (E_lit (mk_lit L_unit)) unk env unit_typ])) unk env option_typ), unkt) in + + (* recurse into pat2 .. patn *) + let new_pat2_pexp = + match rewrite_pat env (P_aux (P_string_append (pats), psa_annot), guards, expr) with + | pat, [], expr -> Pat_aux (Pat_exp (pat, expr), unkt) + | pat, gs, expr -> Pat_aux (Pat_when (pat, fold_typed_guards env gs, expr), unkt) + in + + let inner_match = annot_exp (E_case (drop_exp, [new_pat2_pexp; new_wildcard])) unk env option_typ in + + let outer_match = annot_exp (E_case (func_exp, [Pat_aux (Pat_exp (some_pat, inner_match), unkt); new_wildcard])) unk env option_typ in + + (annot_pat (P_id s_id) unk env string_typ, [], outer_match) + | _ -> (pat, guards, expr) + in + let new_pat, new_guards, new_expr = rewrite_pat env (pat, [], annot_exp (E_app (mk_id "Some", List.map (fun p -> pat_to_exp p) bindings)) unk env option_typ) in + let new_pexp = match new_guards with + | [] -> Pat_aux (Pat_exp (new_pat, new_expr), unkt) + | gs -> Pat_aux (Pat_when (new_pat, fold_typed_guards env gs, new_expr), unkt) + in + let wildcard = mk_pexp (Pat_exp (mk_pat P_wild, mk_exp (E_app (mk_id "None", [mk_lit_exp L_unit])))) in + let new_match = mk_exp (E_case (mk_exp (E_id s_id), [strip_pexp new_pexp; wildcard])) in + let new_fun_def = FD_aux (FD_function (non_rec, no_tannot, effect_pure, [mk_funcl f_id arg_pat new_match]), (unk,())) in + let new_fun_def, env = Type_check.check_fundef env new_fun_def in + List.flatten [new_val_spec; new_fun_def] + +let rewrite_defs_toplevel_string_append (Defs defs) = + let new_defs = ref ([] : tannot def list) in + let rec rewrite_pexp (Pat_aux (pexp_aux, pexp_annot) as pexp) = + (* merge cases of Pat_exp and Pat_when *) + let (P_aux (p_aux, p_annot) as pat, guards, expr) = + match pexp_aux with + | Pat_exp (pat, expr) -> (pat, [], expr) + | Pat_when (pat, guard, expr) -> (pat, [guard], expr) + in + + let env = env_of_annot p_annot in + + let (new_pat, new_guards, new_expr) = + match pat with + | P_aux (P_string_append appends, psa_annot) -> + let f_id = fresh_stringappend_id () in + new_defs := (construct_toplevel_string_append_func env f_id pat) @ !new_defs; + construct_toplevel_string_append_call env f_id (bindings_of_pat pat) (binding_typs_of_pat pat) (fold_typed_guards env guards) expr + | _ -> (pat, guards, expr) + in + + (* un-merge Pat_exp and Pat_when cases *) + let new_pexp = match new_guards with + | [] -> Pat_aux (Pat_exp (new_pat, new_expr), pexp_annot) + | gs -> Pat_aux (Pat_when (new_pat, fold_typed_guards env gs, new_expr), pexp_annot) + in + new_pexp + in + let rewrite def = + new_defs := []; + let alg = { id_exp_alg with pat_aux = (fun (pexp_aux, annot) -> rewrite_pexp (Pat_aux (pexp_aux, annot))) } in + let rewritten = rewrite_def { rewriters_base with rewrite_exp = (fun _ -> fold_exp alg) } def in + !new_defs @ [rewritten] + in + Defs (List.map rewrite defs |> List.flatten) + let rec rewrite_defs_pat_string_append = let rec rewrite_pat env ((pat : tannot pat), (guards : tannot exp list), (expr : tannot exp)) = @@ -4598,6 +4829,7 @@ let if_mono f defs = let rewrite_defs_lem = [ ("realise_mappings", rewrite_defs_realise_mappings); ("remove_mapping_valspecs", remove_mapping_valspecs); + ("toplevel_string_append", rewrite_defs_toplevel_string_append); ("pat_string_append", rewrite_defs_pat_string_append); ("mapping_builtins", rewrite_defs_mapping_patterns); ("mono_rewrites", mono_rewrites); @@ -4647,6 +4879,7 @@ let rewrite_defs_lem = [ let rewrite_defs_coq = [ ("realise_mappings", rewrite_defs_realise_mappings); ("remove_mapping_valspecs", remove_mapping_valspecs); + ("toplevel_string_append", rewrite_defs_toplevel_string_append); ("pat_string_append", rewrite_defs_pat_string_append); ("mapping_builtins", rewrite_defs_mapping_patterns); ("rewrite_undefined", rewrite_undefined_if_gen true); @@ -4690,6 +4923,7 @@ let rewrite_defs_ocaml = [ (* ("undefined", rewrite_undefined); *) ("no_effect_check", (fun defs -> opt_no_effects := true; defs)); ("realise_mappings", rewrite_defs_realise_mappings); + ("toplevel_string_append", rewrite_defs_toplevel_string_append); ("pat_string_append", rewrite_defs_pat_string_append); ("mapping_builtins", rewrite_defs_mapping_patterns); ("rewrite_undefined", rewrite_undefined_if_gen false); @@ -4714,6 +4948,7 @@ let rewrite_defs_ocaml = [ let rewrite_defs_c = [ ("no_effect_check", (fun defs -> opt_no_effects := true; defs)); ("realise_mappings", rewrite_defs_realise_mappings); + ("toplevel_string_append", rewrite_defs_toplevel_string_append); ("pat_string_append", rewrite_defs_pat_string_append); ("mapping_builtins", rewrite_defs_mapping_patterns); ("rewrite_undefined", rewrite_undefined_if_gen false); @@ -4736,6 +4971,7 @@ let rewrite_defs_c = [ let rewrite_defs_interpreter = [ ("no_effect_check", (fun defs -> opt_no_effects := true; defs)); ("realise_mappings", rewrite_defs_realise_mappings); + ("toplevel_string_append", rewrite_defs_toplevel_string_append); ("pat_string_append", rewrite_defs_pat_string_append); ("mapping_builtins", rewrite_defs_mapping_patterns); ("rewrite_undefined", rewrite_undefined_if_gen false); |