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|
(** Functions to load CFIM ASTs from json.
Initially, we used `ppx_derive_yojson` to automate this.
However, `ppx_derive_yojson` expects formatting to be slightly
different from what `serde_rs` generates.
For instance, if you consider the following rust definition:
```
enum t = | V
```
Serializing `t::V` with `serde_rs` will generate: `"V"`.
However, if you consider the following OCaml definition:
```
type t = V
```
Serializing `V` will generate: `["V"]`.
As we consider that the `serde_rs` formatting is more logical, we decided
to implement our own deserializing functions. Moreover, it allows us to
generate a friendlier debugging output in case the deserialization functions
fail.
TODO: we should check that the integer values are in the proper range
*)
open Yojson.Safe
open Identifiers
open Types
type json = t
let ( let* ) o f = match o with Error e -> Error e | Ok x -> f x
let bool_of_json (js : json) : (bool, string) result =
match js with
| `Bool b -> Ok b
| _ -> Error ("bool_of_json: not a bool: " ^ show js)
let int_of_json (js : json) : (int, string) result =
match js with
| `Int i -> Ok i
| _ -> Error ("int_of_json: not an int: " ^ show js)
let char_of_json (_js : json) : (char, string) result =
(* TODO: implement *)
Error "char_of_json: unimplemented"
let rec of_json_list (a_of_json : json -> ('a, string) result) (jsl : json list)
: ('a list, string) result =
match jsl with
| [] -> Ok []
| x :: jsl' ->
let* x = a_of_json x in
let* jsl' = of_json_list a_of_json jsl' in
Ok (x :: jsl')
let pair_of_json (a_of_json : json -> ('a, string) result)
(b_of_json : json -> ('b, string) result) (js : json) :
('a * 'b, string) result =
match js with
| `Tuple [ a; b ] ->
let* a = a_of_json a in
let* b = b_of_json b in
Ok (a, b)
| _ -> Error ("pair_of_json failed on: " ^ show js)
let list_of_json (a_of_json : json -> ('a, string) result) (js : json) :
('a list, string) result =
match js with
| `List jsl -> of_json_list a_of_json jsl
| _ -> Error ("list_of_json: not a list: " ^ show js)
let string_of_json (js : json) : (string, string) result =
match js with
| `String str -> Ok str
| _ -> Error ("string_of_json: not a string: " ^ show js)
let option_of_json (a_of_json : json -> ('a, string) result) (js : json) :
('a option, string) result =
match js with
| `Variant ("Some", Some x) ->
let* x = a_of_json x in
Ok (Some x)
| `Variant ("None", None) -> Ok None
| _ -> Error ("option_of_json failed on: " ^ show js)
let string_option_of_json (js : json) : (string option, string) result =
option_of_json string_of_json js
let name_of_json (js : json) : (name, string) result =
list_of_json string_of_json js
let type_var_of_json (js : json) : (type_var, string) result =
match js with
| `Assoc [ ("index", index); ("name", name) ] ->
let* index = TypeVarId.id_of_json index in
let* name = string_of_json name in
Ok { tv_index = index; tv_name = name }
| _ -> Error ("type_var_of_json failed on:" ^ show js)
let region_var_of_json (js : json) : (region_var, string) result =
match js with
| `Assoc [ ("index", index); ("name", name) ] ->
let* index = RegionVarId.id_of_json index in
let* name = string_option_of_json name in
Ok { rv_index = index; rv_name = name }
| _ -> Error ("region_var_of_json failed on:" ^ show js)
let region_of_json (js : json) : (RegionVarId.id region, string) result =
match js with
| `Variant ("Static", None) -> Ok Static
| `Variant ("Var", Some rid) ->
let* rid = RegionVarId.id_of_json rid in
Ok (Var rid)
| _ -> Error ("region_of_json failed on:" ^ show js)
let erased_region_of_json (js : json) : (erased_region, string) result =
match js with
| `Variant ("Erased", None) -> Ok Erased
| _ -> Error ("erased_region_of_json failed on:" ^ show js)
let integer_type_of_json (js : json) : (integer_type, string) result =
match js with
| `Variant ("Isize", None) -> Ok Isize
| `Variant ("I8", None) -> Ok I8
| `Variant ("I16", None) -> Ok I16
| `Variant ("I32", None) -> Ok I32
| `Variant ("I64", None) -> Ok I64
| `Variant ("I128", None) -> Ok I128
| `Variant ("Usize", None) -> Ok Usize
| `Variant ("U8", None) -> Ok U8
| `Variant ("U16", None) -> Ok U16
| `Variant ("U32", None) -> Ok U32
| `Variant ("U64", None) -> Ok U64
| `Variant ("U128", None) -> Ok U128
| _ -> Error ("integer_type_of_json failed on:" ^ show js)
let ref_kind_of_json (js : json) : (ref_kind, string) result =
match js with
| `Variant ("Mut", None) -> Ok Mut
| `Variant ("Shared", None) -> Ok Shared
| _ -> Error ("ref_kind_of_json failed on:" ^ show js)
let assumed_ty_of_json (js : json) : (assumed_ty, string) result =
match js with
| `Variant ("Box", None) -> Ok Box
| _ -> Error ("assumed_ty_of_json failed on:" ^ show js)
let rec ty_of_json (r_of_json : json -> ('r, string) result) (js : json) :
('r ty, string) result =
match js with
| `Variant ("Adt", Some (`Tuple [ id; regions; types ])) ->
let* id = TypeDefId.id_of_json id in
let* regions = list_of_json r_of_json regions in
let* types = list_of_json (ty_of_json r_of_json) types in
Ok (Adt (id, regions, types))
| `Variant ("TypeVar", Some id) ->
let* id = TypeVarId.id_of_json id in
Ok (TypeVar id)
| `Variant ("Bool", None) -> Ok Bool
| `Variant ("Char", None) -> Ok Char
| `Variant ("Never", None) -> Ok Never
| `Variant ("Integer", Some int_ty) ->
let* int_ty = integer_type_of_json int_ty in
Ok (Integer int_ty)
| `Variant ("Str", None) -> Ok Str
| `Variant ("Array", Some ty) ->
let* ty = ty_of_json r_of_json ty in
Ok (Array ty)
| `Variant ("Slice", Some ty) ->
let* ty = ty_of_json r_of_json ty in
Ok (Slice ty)
| `Variant ("Ref", Some (`Tuple [ region; ty; ref_kind ])) ->
let* region = r_of_json region in
let* ty = ty_of_json r_of_json ty in
let* ref_kind = ref_kind_of_json ref_kind in
Ok (Ref (region, ty, ref_kind))
| `Variant ("Tuple", Some types) ->
let* types = list_of_json (ty_of_json r_of_json) types in
Ok (Tuple types)
| `Variant ("Assumed", Some (`Tuple [ assumed_ty; regions; types ])) ->
let* assumed_ty = assumed_ty_of_json assumed_ty in
let* regions = list_of_json r_of_json regions in
let* types = list_of_json (ty_of_json r_of_json) types in
Ok (Assumed (assumed_ty, regions, types))
| _ -> Error ("ty_of_json failed on:" ^ show js)
let rty_of_json (js : json) : (rty, string) result =
ty_of_json region_of_json js
let ety_of_json (js : json) : (ety, string) result =
ty_of_json erased_region_of_json js
let field_of_json (js : json) : (field, string) result =
match js with
| `Assoc [ ("name", name); ("ty", ty) ] ->
let* name = string_of_json name in
let* ty = rty_of_json ty in
Ok { field_name = name; field_ty = ty }
| _ -> Error ("field_of_json failed on:" ^ show js)
let variant_of_json (js : json) : (variant, string) result =
match js with
| `Assoc [ ("name", name); ("fields", fields) ] ->
let* name = string_of_json name in
let* fields = FieldId.vector_of_json field_of_json fields in
Ok { variant_name = name; fields }
| _ -> Error ("variant_of_json failed on:" ^ show js)
let type_def_kind_of_json (js : json) : (type_def_kind, string) result =
match js with
| `Variant ("Struct", Some fields) ->
let* fields = FieldId.vector_of_json field_of_json fields in
Ok (Struct fields)
| `Variant ("Enum", Some variants) ->
let* variants = VariantId.vector_of_json variant_of_json variants in
Ok (Enum variants)
| _ -> Error ("type_def_kind_of_json failed on:" ^ show js)
let type_def_of_json (js : json) : (type_def, string) result =
match js with
| `Assoc
[
("def_id", def_id);
("name", name);
("region_params", region_params);
("type_params", type_params);
("kind", kind);
] ->
let* def_id = TypeDefId.id_of_json def_id in
let* name = name_of_json name in
let* region_params =
RegionVarId.vector_of_json region_var_of_json region_params
in
let* type_params =
TypeVarId.vector_of_json type_var_of_json type_params
in
let* kind = type_def_kind_of_json kind in
Ok { def_id; name; region_params; type_params; kind }
| _ -> Error ("type_def_of_json failed on:" ^ show js)
open Values
let var_of_json (js : json) : (var, string) result =
match js with
| `Assoc [ ("index", index); ("name", name); ("ty", ty) ] ->
let* index = VarId.id_of_json index in
let* name = string_option_of_json name in
let* ty = ety_of_json ty in
Ok { index; name; ty }
| _ -> Error ("var_of_json failed on:" ^ show js)
let big_int_of_json (js : json) : (big_int, string) result =
match js with
| `Int i -> Ok (Z.of_int i)
| `Intlit is -> Ok (Z.of_string is)
| _ -> Error ("big_int_of_json failed on: " ^ show js)
let scalar_value_of_json (js : json) : (scalar_value, string) result =
match js with
| `Variant ("Isize", Some bi) ->
let* bi = big_int_of_json bi in
Ok (Isize bi)
| `Variant ("I8", Some bi) ->
let* bi = big_int_of_json bi in
Ok (I8 bi)
| `Variant ("I16", Some bi) ->
let* bi = big_int_of_json bi in
Ok (I16 bi)
| `Variant ("I32", Some bi) ->
let* bi = big_int_of_json bi in
Ok (I32 bi)
| `Variant ("I64", Some bi) ->
let* bi = big_int_of_json bi in
Ok (I64 bi)
| `Variant ("I128", Some bi) ->
let* bi = big_int_of_json bi in
Ok (I128 bi)
| `Variant ("Usize", Some bi) ->
let* bi = big_int_of_json bi in
Ok (Usize bi)
| `Variant ("U8", Some bi) ->
let* bi = big_int_of_json bi in
Ok (U8 bi)
| `Variant ("U16", Some bi) ->
let* bi = big_int_of_json bi in
Ok (U16 bi)
| `Variant ("U32", Some bi) ->
let* bi = big_int_of_json bi in
Ok (U32 bi)
| `Variant ("U64", Some bi) ->
let* bi = big_int_of_json bi in
Ok (U64 bi)
| `Variant ("U128", Some bi) ->
let* bi = big_int_of_json bi in
Ok (U128 bi)
| _ -> Error ("scalar_value_of_json failed on:" ^ show js)
let constant_value_of_json (js : json) : (constant_value, string) result =
match js with
| `Variant ("Scalar", Some scalar_value) ->
let* scalar_value = scalar_value_of_json scalar_value in
Ok (Scalar scalar_value)
| `Variant ("Bool", Some v) ->
let* v = bool_of_json v in
Ok (Bool v)
| `Variant ("Char", Some v) ->
let* v = char_of_json v in
Ok (Char v)
| `Variant ("String", Some v) ->
let* v = string_of_json v in
Ok (String v)
| _ -> Error ("constant_value_of_json failed on:" ^ show js)
open Expressions
let field_proj_kind_of_json (js : json) : (field_proj_kind, string) result =
match js with
| `Variant ("ProjAdt", Some (`Tuple [ def_id; opt_variant_id ])) ->
let* def_id = TypeDefId.id_of_json def_id in
let* opt_variant_id =
option_of_json VariantId.id_of_json opt_variant_id
in
Ok (ProjAdt (def_id, opt_variant_id))
| `Variant ("ProjTuple", Some i) ->
let* i = int_of_json i in
Ok (ProjTuple i)
| _ -> Error ("field_proj_kind_of_json failed on:" ^ show js)
let projection_elem_of_json (js : json) : (projection_elem, string) result =
match js with
| `Variant ("Deref", None) -> Ok Deref
| `Variant ("DerefBox", None) -> Ok DerefBox
| `Variant ("Field", Some (`Tuple [ proj_kind; field_id ])) ->
let* proj_kind = field_proj_kind_of_json proj_kind in
let* field_id = FieldId.id_of_json field_id in
Ok (Field (proj_kind, field_id))
| `Variant ("Downcast", Some variant_id) ->
let* variant_id = VariantId.id_of_json variant_id in
Ok (Downcast variant_id)
| _ -> Error ("projection_elem_of_json failed on:" ^ show js)
let projection_of_json (js : json) : (projection, string) result =
list_of_json projection_elem_of_json js
let place_of_json (js : json) : (place, string) result =
match js with
| `Assoc [ ("var_id", var_id); ("projection", projection) ] ->
let* var_id = VarId.id_of_json var_id in
let* projection = projection_of_json projection in
Ok { var_id; projection }
| _ -> Error ("place_of_json failed on:" ^ show js)
let borrow_kind_of_json (js : json) : (borrow_kind, string) result =
match js with
| `Variant ("Shared", None) -> Ok Shared
| `Variant ("Mut", None) -> Ok Mut
| `Variant ("TwoPhaseMut", None) -> Ok TwoPhaseMut
| _ -> Error ("borrow_kind_of_json failed on:" ^ show js)
let unop_of_json (js : json) : (unop, string) result =
match js with
| `Variant ("Not", None) -> Ok Not
| `Variant ("Neg", None) -> Ok Neg
| _ -> Error ("unop_of_json failed on:" ^ show js)
let binop_of_json (js : json) : (binop, string) result =
match js with
| `Variant ("BitXor", None) -> Ok BitXor
| `Variant ("BitAnd", None) -> Ok BitAnd
| `Variant ("BitOr", None) -> Ok BitOr
| `Variant ("Eq", None) -> Ok Eq
| `Variant ("Lt", None) -> Ok Lt
| `Variant ("Le", None) -> Ok Le
| `Variant ("Ne", None) -> Ok Ne
| `Variant ("Ge", None) -> Ok Ge
| `Variant ("Gt", None) -> Ok Gt
| `Variant ("Div", None) -> Ok Div
| `Variant ("Rem", None) -> Ok Rem
| `Variant ("Add", None) -> Ok Add
| `Variant ("Sub", None) -> Ok Sub
| `Variant ("Mul", None) -> Ok Mul
| `Variant ("Shl", None) -> Ok Shl
| `Variant ("Shr", None) -> Ok Shr
| _ -> Error ("binop_of_json failed on:" ^ show js)
let operand_constant_value_of_json (js : json) :
(operand_constant_value, string) result =
match js with
| `Variant ("ConstantValue", Some cv) ->
let* cv = constant_value_of_json cv in
Ok (ConstantValue cv)
| `Variant ("ConstantAdt", Some id) ->
let* id = TypeDefId.id_of_json id in
Ok (ConstantAdt id)
| `Variant ("Unit", None) -> Ok Unit
| _ -> Error ("operand_constant_value_of_json failed on:" ^ show js)
let operand_of_json (js : json) : (operand, string) result =
match js with
| `Variant ("Copy", Some place) ->
let* place = place_of_json place in
Ok (Copy place)
| `Variant ("Move", Some place) ->
let* place = place_of_json place in
Ok (Move place)
| `Variant ("Constant", Some (`Tuple [ ty; cv ])) ->
let* ty = ety_of_json ty in
let* cv = operand_constant_value_of_json cv in
Ok (Constant (ty, cv))
| _ -> Error ("operand_of_json failed on:" ^ show js)
let aggregate_kind_of_json (js : json) : (aggregate_kind, string) result =
match js with
| `Variant ("AggregatedTuple", None) -> Ok AggregatedTuple
| `Variant ("AggregatedAdt", Some (`Tuple [ id; opt_variant_id ])) ->
let* id = TypeDefId.id_of_json id in
let* opt_variant_id =
option_of_json VariantId.id_of_json opt_variant_id
in
Ok (AggregatedAdt (id, opt_variant_id))
| _ -> Error ("aggregate_kind_of_json failed on:" ^ show js)
let rvalue_of_json (js : json) : (rvalue, string) result =
match js with
| `Variant ("Use", Some op) ->
let* op = operand_of_json op in
Ok (Use op)
| `Variant ("Ref", Some (`Tuple [ place; borrow_kind ])) ->
let* place = place_of_json place in
let* borrow_kind = borrow_kind_of_json borrow_kind in
Ok (Ref (place, borrow_kind))
| `Variant ("UnaryOp", Some (`Tuple [ unop; op ])) ->
let* unop = unop_of_json unop in
let* op = operand_of_json op in
Ok (UnaryOp (unop, op))
| `Variant ("BinaryOp", Some (`Tuple [ binop; op1; op2 ])) ->
let* binop = binop_of_json binop in
let* op1 = operand_of_json op1 in
let* op2 = operand_of_json op2 in
Ok (BinaryOp (binop, op1, op2))
| `Variant ("Discriminant", Some place) ->
let* place = place_of_json place in
Ok (Discriminant place)
| `Variant ("Aggregate", Some (`Tuple [ aggregate_kind; ops ])) ->
let* aggregate_kind = aggregate_kind_of_json aggregate_kind in
let* ops = list_of_json operand_of_json ops in
Ok (Aggregate (aggregate_kind, ops))
| _ -> Error ("rvalue_of_json failed on:" ^ show js)
open CfimAst
let assumed_fun_id_of_json (js : json) : (assumed_fun_id, string) result =
match js with
| `Variant ("BoxNew", None) -> Ok BoxNew
| `Variant ("BoxDeref", None) -> Ok BoxDeref
| `Variant ("BoxDerefMut", None) -> Ok BoxDerefMut
| `Variant ("BoxFree", None) -> Ok BoxFree
| _ -> Error ("assumed_fun_id_of_json failed on:" ^ show js)
let fun_id_of_json (js : json) : (fun_id, string) result =
match js with
| `Variant ("Local", Some id) ->
let* id = FunDefId.id_of_json id in
Ok (Local id)
| `Variant ("BoxDeref", Some fid) ->
let* fid = assumed_fun_id_of_json fid in
Ok (Assumed fid)
| _ -> Error ("fun_id_of_json failed on:" ^ show js)
let assertion_of_json (js : json) : (assertion, string) result =
match js with
| `Assoc [ ("cond", cond); ("expected", expected) ] ->
let* cond = operand_of_json cond in
let* expected = bool_of_json expected in
Ok { cond; expected }
| _ -> Error ("assertion_of_json failed on:" ^ show js)
let fun_sig_of_json (js : json) : (fun_sig, string) result =
match js with
| `Assoc
[
("region_params", region_params);
("num_early_bound_regions", num_early_bound_regions);
("type_params", type_params);
("inputs", inputs);
("output", output);
] ->
let* region_params =
RegionVarId.vector_of_json region_var_of_json region_params
in
let* num_early_bound_regions = int_of_json num_early_bound_regions in
let* type_params =
TypeVarId.vector_of_json type_var_of_json type_params
in
let* inputs = VarId.vector_of_json rty_of_json inputs in
let* output = rty_of_json output in
Ok { region_params; num_early_bound_regions; type_params; inputs; output }
| _ -> Error ("fun_sig_of_json failed on:" ^ show js)
let call_of_json (js : json) : (call, string) result =
match js with
| `Assoc
[
("func", func);
("region_params", region_params);
("type_params", type_params);
("args", args);
("dest", dest);
] ->
let* func = fun_id_of_json func in
let* region_params = list_of_json erased_region_of_json region_params in
let* type_params = list_of_json ety_of_json type_params in
let* args = list_of_json operand_of_json args in
let* dest = place_of_json dest in
Ok { func; region_params; type_params; args; dest }
| _ -> Error ("call_of_json failed on:" ^ show js)
let statement_of_json (js : json) : (statement, string) result =
match js with
| `Variant ("Assign", Some (`Tuple [ place; rvalue ])) ->
let* place = place_of_json place in
let* rvalue = rvalue_of_json rvalue in
Ok (Assign (place, rvalue))
| `Variant ("FakeRead", Some place) ->
let* place = place_of_json place in
Ok (FakeRead place)
| `Variant ("SetDiscriminant", Some (`Tuple [ place; variant_id ])) ->
let* place = place_of_json place in
let* variant_id = VariantId.id_of_json variant_id in
Ok (SetDiscriminant (place, variant_id))
| `Variant ("Drop", Some place) ->
let* place = place_of_json place in
Ok (Drop place)
| `Variant ("Assert", Some assertion) ->
let* assertion = assertion_of_json assertion in
Ok (Assert assertion)
| `Variant ("Call", Some call) ->
let* call = call_of_json call in
Ok (Call call)
| `Variant ("Panic", None) -> Ok Panic
| `Variant ("Return", None) -> Ok Return
| `Variant ("Break", Some i) ->
let* i = int_of_json i in
Ok (Break i)
| `Variant ("Continue", Some i) ->
let* i = int_of_json i in
Ok (Continue i)
| `Variant ("Nop", None) -> Ok Nop
| _ -> Error ("statement_of_json failed on:" ^ show js)
let rec expression_of_json (js : json) : (expression, string) result =
match js with
| `Variant ("Statement", Some statement) ->
let* statement = statement_of_json statement in
Ok (Statement statement)
| `Variant ("Sequence", Some (`Tuple [ e1; e2 ])) ->
let* e1 = expression_of_json e1 in
let* e2 = expression_of_json e2 in
Ok (Sequence (e1, e2))
| `Variant ("Switch", Some (`Tuple [ op; tgt ])) ->
let* op = operand_of_json op in
let* tgt = switch_targets_of_json tgt in
Ok (Switch (op, tgt))
| `Variant ("Loop", Some e) ->
let* e = expression_of_json e in
Ok (Loop e)
| _ -> Error ("expression_of_json failed on:" ^ show js)
and switch_targets_of_json (js : json) : (switch_targets, string) result =
match js with
| `Variant ("If", Some (`Tuple [ e1; e2 ])) ->
let* e1 = expression_of_json e1 in
let* e2 = expression_of_json e2 in
Ok (If (e1, e2))
| `Variant ("SwitchInt", Some (`Tuple [ int_ty; tgts; otherwise ])) ->
let* int_ty = integer_type_of_json int_ty in
let* tgts =
list_of_json (pair_of_json scalar_value_of_json expression_of_json) tgts
in
let* otherwise = expression_of_json otherwise in
Ok (SwitchInt (int_ty, tgts, otherwise))
| _ -> Error ("switch_targets_of_json failed on:" ^ show js)
|