[racerd] merge Choice and Attribute modules

Summary:
Both modules define properties the analysis maps to addresses, there is no reason to have two modules for this.

Also remove an instance of `Caml.Not_found` usage.

Reviewed By: jberdine

Differential Revision: D20558683

fbshipit-source-id: eacafd780

infer/src/concurrency/RacerD.ml

@@ -269,7 +269,7 @@ module TransferFunctions (CFG : ProcCfg.S) = struct
           {astate with threads= ThreadsDomain.AnyThreadButSelf}
       | MainThreadIfTrue ->
           let attribute_map =
-            AttributeMapDomain.add_attribute ret_access_exp (Choice Choice.OnMainThread)
+            AttributeMapDomain.add_attribute ret_access_exp Attribute.OnMainThread
               astate.attribute_map
           in
           {astate with attribute_map}
@@ -301,7 +301,7 @@ module TransferFunctions (CFG : ProcCfg.S) = struct
             ; threads= update_for_lock_use astate.threads }
         | LockedIfTrue _ | GuardLockedIfTrue _ ->
             let attribute_map =
-              AttributeMapDomain.add_attribute ret_access_exp (Choice Choice.LockHeld)
+              AttributeMapDomain.add_attribute ret_access_exp Attribute.LockHeld
                 astate.attribute_map
             in
             {astate with attribute_map; threads= update_for_lock_use astate.threads}
@@ -397,18 +397,20 @@ module TransferFunctions (CFG : ProcCfg.S) = struct
 
   let do_assume formals assume_exp loc proc_data (astate : Domain.t) =
     let open Domain in
-    let add_choice bool_value (acc : Domain.t) = function
-      | Choice.LockHeld ->
+    let apply_choice bool_value (acc : Domain.t) = function
+      | Attribute.LockHeld ->
           let locks =
             if bool_value then LocksDomain.acquire_lock acc.locks
             else LocksDomain.release_lock acc.locks
           in
           {acc with locks}
-      | Choice.OnMainThread ->
+      | Attribute.OnMainThread ->
           let threads =
             if bool_value then ThreadsDomain.AnyThreadButSelf else ThreadsDomain.AnyThread
           in
           {acc with threads}
+      | Attribute.Functional ->
+          acc
     in
     let accesses =
       add_access formals loc ~is_write_access:false astate.locks astate.threads astate.ownership
@@ -422,7 +424,7 @@ module TransferFunctions (CFG : ProcCfg.S) = struct
                  let choices = AttributeMapDomain.get_choices access_expr astate.attribute_map in
                  (* prune (prune_exp) can only evaluate to true if the choice is [bool_value].
                     add the constraint that the choice must be [bool_value] to the state *)
-                 List.fold ~f:(add_choice bool_value) ~init choices )
+                 List.fold ~f:(apply_choice bool_value) ~init choices )
       | _ ->
           astate
     in

infer/src/concurrency/RacerDDomain.ml

@@ -438,26 +438,18 @@ module OwnershipDomain = struct
         AccessSnapshot.OwnershipPrecondition.False
 end
 
-module Choice = struct
-  type t = OnMainThread | LockHeld [@@deriving compare]
+module Attribute = struct
+  type t = Functional | OnMainThread | LockHeld [@@deriving compare]
 
   let pp fmt = function
+    | Functional ->
+        F.pp_print_string fmt "Functional"
     | OnMainThread ->
         F.pp_print_string fmt "OnMainThread"
     | LockHeld ->
         F.pp_print_string fmt "LockHeld"
 end
 
-module Attribute = struct
-  type t = Functional | Choice of Choice.t [@@deriving compare]
-
-  let pp fmt = function
-    | Functional ->
-        F.pp_print_string fmt "Functional"
-    | Choice choice ->
-        Choice.pp fmt choice
-end
-
 module AttributeSetDomain = AbstractDomain.InvertedSet (Attribute)
 
 module AttributeMapDomain = struct
@@ -468,16 +460,17 @@ module AttributeMapDomain = struct
 
 
   let has_attribute access_expression attribute t =
-    try find access_expression t |> AttributeSetDomain.mem attribute with Caml.Not_found -> false
+    find_opt access_expression t |> Option.exists ~f:(AttributeSetDomain.mem attribute)
 
 
   let get_choices access_expression t =
-    try
-      let attributes = find access_expression t in
-      AttributeSetDomain.fold
-        (fun cc acc -> match cc with Attribute.Choice c -> c :: acc | _ -> acc)
-        attributes []
-    with Caml.Not_found -> []
+    match find_opt access_expression t with
+    | None ->
+        []
+    | Some attributes ->
+        AttributeSetDomain.fold
+          (fun cc acc -> match cc with OnMainThread | LockHeld -> cc :: acc | _ -> acc)
+          attributes []
 
 
   let add_attribute access_expression attribute t =
@@ -492,8 +485,8 @@ module AttributeMapDomain = struct
 
   let rec attributes_of_expr attribute_map (e : HilExp.t) =
     match e with
-    | AccessExpression access_expr -> (
-      try find access_expr attribute_map with Caml.Not_found -> AttributeSetDomain.empty )
+    | AccessExpression access_expr ->
+        find_opt access_expr attribute_map |> Option.value ~default:AttributeSetDomain.empty
     | Constant _ ->
         AttributeSetDomain.singleton Attribute.Functional
     | Exception expr (* treat exceptions as transparent wrt attributes *) | Cast (_, expr) ->

infer/src/concurrency/RacerDDomain.mli

@@ -158,19 +158,11 @@ module OwnershipDomain : sig
   val get_precondition : AccessExpression.t -> t -> AccessSnapshot.OwnershipPrecondition.t
 end
 
-(** attribute attached to a boolean variable specifying what it means when the boolean is true *)
-module Choice : sig
-  type t =
-    | OnMainThread  (** the current procedure is running on the main thread *)
-    | LockHeld  (** a lock is currently held *)
-
-  include PrettyPrintable.PrintableOrderedType with type t := t
-end
-
 module Attribute : sig
   type t =
     | Functional  (** holds a value returned from a callee marked [@Functional] *)
-    | Choice of Choice.t  (** holds a boolean choice variable *)
+    | OnMainThread  (** boolean is true if the current procedure is running on the main thread *)
+    | LockHeld  (** boolean is true if a lock is currently held *)
 
   include PrettyPrintable.PrintableOrderedType with type t := t
 end
@@ -190,7 +182,7 @@ module AttributeMapDomain : sig
 
   val has_attribute : AccessExpression.t -> Attribute.t -> t -> bool
 
-  val get_choices : AccessExpression.t -> t -> Choice.t list
+  val get_choices : AccessExpression.t -> t -> Attribute.t list
   (** get the choice attributes associated with the given access path *)
 
   val add_attribute : AccessExpression.t -> Attribute.t -> t -> t