From 5dd233cf1ed8fad120f79f6e002d15607b520cc9 Mon Sep 17 00:00:00 2001 From: Son Ho Date: Mon, 22 Nov 2021 21:54:07 +0100 Subject: Make progress on write_projection --- src/Identifiers.ml | 10 +++++++ src/Interpreter.ml | 83 +++++++++++++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 92 insertions(+), 1 deletion(-) (limited to 'src') diff --git a/src/Identifiers.ml b/src/Identifiers.ml index 04c5427b..dbe2ae83 100644 --- a/src/Identifiers.ml +++ b/src/Identifiers.ml @@ -1,3 +1,5 @@ +open Errors + (** Signature for a module describing an identifier. We often need identifiers (for definitions, variables, etc.) and in @@ -23,6 +25,8 @@ module type Id = sig val nth_opt : 'a vector -> id -> 'a option + val update_nth : 'a vector -> id -> 'a -> 'a vector + module Set : Set.S with type elt = id val set_to_string : Set.t -> string @@ -63,6 +67,12 @@ module IdGen () : Id = struct let nth_opt v id = List.nth_opt v id + let rec update_nth vec id v = + match (vec, id) with + | [], _ -> unreachable __LOC__ + | _ :: vec', 0 -> v :: vec' + | x :: vec', _ -> x :: update_nth vec' (id - 1) v + module Set = Set.Make (struct type t = id diff --git a/src/Interpreter.ml b/src/Interpreter.ml index c5a1dad1..3dbb5020 100644 --- a/src/Interpreter.ml +++ b/src/Interpreter.ml @@ -536,7 +536,7 @@ let rec read_projection (config : config) (access : path_access) (env : env) (* We can enter shared loans only if we are in "read" mode *) | Read, SharedLoan (_, sv) -> enter_loans sv | Write, SharedLoan (bids, _) -> Error (FailSharedLoan bids) - (* We can always enter mutable loans *) + (* We always have to end mutable loans *) | _, MutLoan bid -> Error (FailMutLoan bid)) | _ -> Ok v in @@ -581,6 +581,7 @@ let rec read_projection (config : config) (access : path_access) (env : env) read_projection config access env p' sv | Write, SharedBorrow _ -> unreachable __LOC__ | _, MutBorrow (_, bv) -> read_projection config access env p' bv + (* We need to activate inactivated mutable borrows *) | _, InactivatedMutBorrow bid -> Error (FailInactivatedMutBorrow bid)) (* Remaining cases: error. We enumerate all the value variants @@ -606,6 +607,86 @@ let read_place (config : config) (access : path_access) (p : place) (env0 : env) in read_in_env env0 +(** Update the value at the end of a projection *) +let rec write_projection (config : config) (new_value : typed_value) + (p : projection) (v : typed_value) : typed_value path_access_result = + match p with + | [] -> Ok v + | pe :: p' -> ( + (* Match on the projection element and the value *) + match (pe, v.value) with + (* Field projection *) + | Field (ProjAdt (_def_id, opt_variant_id), field_id), Adt adt -> ( + (* Check that the projection is consistent with the current value *) + (match (opt_variant_id, adt.variant_id) with + | None, None -> () + | Some vid, Some vid' -> if vid <> vid' then unreachable __LOC__ + | _ -> unreachable __LOC__); + (* Actually project *) + match FieldId.nth_opt adt.field_values field_id with + | None -> unreachable __LOC__ + | Some fv -> ( + (* Update the field value *) + match write_projection config new_value p fv with + | Error err -> Error err + | Ok nfv -> + (* Reinsert the field value *) + let nvalues = + FieldId.update_nth adt.field_values field_id nfv + in + let nadt = Adt { adt with field_values = nvalues } in + Ok { v with value = nadt })) + (* Tuples *) + | Field (ProjTuple _, field_id), Tuple values -> ( + (* Project *) + match FieldId.nth_opt values field_id with + | None -> unreachable __LOC__ + | Some fv -> ( + (* Update the field value *) + match write_projection config new_value p fv with + | Error err -> Error err + | Ok nfv -> + (* Reinsert the field value *) + let nvalues = FieldId.update_nth values field_id nfv in + let ntuple = Tuple nvalues in + Ok { v with value = ntuple })) + (* If we reach Bottom, it may mean we need to expand an uninitialized + * enumeration value *) + | Field (ProjAdt (_, Some _variant_id), _), Bottom -> + Error (FailBottom (1 + List.length p', pe, v.ty)) + (* Symbolic value: needs to be expanded *) + | _, Symbolic sp -> + assert (config.mode = SymbolicMode); + (* Expand the symbolic value *) + Error (FailSymbolic (pe, sp)) + (* Box dereferencement *) + | DerefBox, Assumed (Box bv) -> ( + (* Update the boxed value *) + match write_projection config new_value p' bv with + | Error err -> Error err + | Ok nbv -> Ok { v with value = Assumed (Box nbv) }) + (* Borrow dereferencement *) + | Deref, Borrow bc -> ( + match bc with + | SharedBorrow _ -> + (* We can't update inside shared borrows *) + unreachable __LOC__ + | MutBorrow (bid, bv) -> ( + match write_projection config new_value p' bv with + | Error err -> Error err + | Ok nbv -> Ok { v with value = Borrow (MutBorrow (bid, nbv)) }) + (* We need to activate inactivated mutable borrows *) + | InactivatedMutBorrow bid -> Error (FailInactivatedMutBorrow bid)) + (* We can never enter loans *) + | _, Loan (SharedLoan (bids, _)) -> Error (FailSharedLoan bids) + (* We also always have to end mutable loans *) + | _, Loan (MutLoan bid) -> Error (FailMutLoan bid) + (* Remaining cases: error. We enumerate all the value variants + * on purpose, to make sure we statically catch errors if we + * modify the [value] definition. *) + | _, (Concrete _ | Adt _ | Tuple _ | Bottom | Assumed _ | Borrow _) -> + unreachable __LOC__) + (* (** Update the value at the end of a projection *) let rec write_projection (config : config) (nv : typed_value) (p : projection) -- cgit v1.2.3