[cfg] rename `Cfg.is_proc_cfg_connected` to `Procdesc.is_connected`

Summary: Moving this function since it's about a single procdesc. Slight rewrite too.

Reviewed By: da319

Differential Revision: D8030494

fbshipit-source-id: f7cc58e

infer/src/IR/Cfg.ml

@@ -53,71 +53,6 @@ let iter_all_nodes ?(sorted= false) cfg ~f =
     |> List.iter ~f:(fun (_, d, n) -> f d n)
 
 
-let proc_cfg_broken_for_node proc_desc =
-  let is_exit_node n =
-    match Procdesc.Node.get_kind n with Procdesc.Node.Exit_node _ -> true | _ -> false
-  in
-  let is_between_join_and_exit_node n =
-    match Procdesc.Node.get_kind n with
-    | Procdesc.Node.Stmt_node "between_join_and_exit" | Procdesc.Node.Stmt_node "Destruction" -> (
-      match Procdesc.Node.get_succs n with [n'] when is_exit_node n' -> true | _ -> false )
-    | _ ->
-        false
-  in
-  let rec is_consecutive_join_nodes n visited =
-    match Procdesc.Node.get_kind n with
-    | Procdesc.Node.Join_node
-      -> (
-        if Procdesc.NodeSet.mem n visited then false
-        else
-          let succs = Procdesc.Node.get_succs n in
-          match succs with
-          | [n'] ->
-              is_consecutive_join_nodes n' (Procdesc.NodeSet.add n visited)
-          | _ ->
-              false )
-    | _ ->
-        is_between_join_and_exit_node n
-  in
-  let find_broken_node n =
-    let succs = Procdesc.Node.get_succs n in
-    let preds = Procdesc.Node.get_preds n in
-    match Procdesc.Node.get_kind n with
-    | Procdesc.Node.Start_node _ ->
-        if List.is_empty succs || not (List.is_empty preds) then Some `Other else None
-    | Procdesc.Node.Exit_node _ ->
-        if not (List.is_empty succs) || List.is_empty preds then Some `Other else None
-    | Procdesc.Node.Stmt_node _ | Procdesc.Node.Prune_node _ | Procdesc.Node.Skip_node _ ->
-        if List.is_empty succs || List.is_empty preds then Some `Other else None
-    | Procdesc.Node.Join_node ->
-        (* Join node has the exception that it may be without predecessors
-         and pointing to between_join_and_exit which points to an exit node.
-         This happens when the if branches end with a return.
-         Nested if statements, where all branches have return statements,
-         introduce a sequence of join nodes *)
-        if
-          (List.is_empty preds && not (is_consecutive_join_nodes n Procdesc.NodeSet.empty))
-          || (not (List.is_empty preds) && List.is_empty succs)
-        then Some `Join
-        else None
-  in
-  let rec find_first_broken nodes res_broken_node =
-    match nodes with
-    | [] ->
-        res_broken_node
-    | n :: nodes' ->
-        let broken_node = find_broken_node n in
-        match broken_node with
-        | None ->
-            find_first_broken nodes' res_broken_node
-        | Some `Join ->
-            find_first_broken nodes' broken_node
-        | Some `Other ->
-            broken_node
-  in
-  find_first_broken (Procdesc.get_nodes proc_desc) None
-
-
 let load_statement =
   ResultsDatabase.register_statement "SELECT cfgs FROM source_files WHERE source_file = :k"
 

infer/src/IR/Cfg.mli

@@ -32,9 +32,6 @@ val create_proc_desc : t -> ProcAttributes.t -> Procdesc.t
 val iter_all_nodes : ?sorted:bool -> t -> f:(Procdesc.t -> Procdesc.Node.t -> unit) -> unit
 (** Iterate over all the nodes in the cfg *)
 
-val proc_cfg_broken_for_node : Procdesc.t -> [`Join | `Other] option
-(** checks whether a cfg for the given procdesc is connected or not *)
-
 val save_attributes : SourceFile.t -> t -> unit
 (** Save the .attr files for the procedures in the cfg. *)
 

infer/src/IR/Procdesc.ml

@@ -815,3 +815,68 @@ let specialize_with_block_args callee_pdesc pname_with_block_args block_args =
     "signature of specialized method %a@." pp_signature resolved_pdesc ;
   convert_cfg ~callee_pdesc ~resolved_pdesc
     ~f_instr_list:(specialize_with_block_args_instrs resolved_pdesc substitutions)
+
+
+let is_connected proc_desc =
+  let is_exit_node n = match Node.get_kind n with Node.Exit_node _ -> true | _ -> false in
+  let is_between_join_and_exit_node n =
+    match Node.get_kind n with
+    | Node.Stmt_node "between_join_and_exit" | Node.Stmt_node "Destruction" -> (
+      match Node.get_succs n with [n'] when is_exit_node n' -> true | _ -> false )
+    | _ ->
+        false
+  in
+  let rec is_consecutive_join_nodes n visited =
+    match Node.get_kind n with
+    | Node.Join_node
+      -> (
+        if NodeSet.mem n visited then false
+        else
+          let succs = Node.get_succs n in
+          match succs with
+          | [n'] ->
+              is_consecutive_join_nodes n' (NodeSet.add n visited)
+          | _ ->
+              false )
+    | _ ->
+        is_between_join_and_exit_node n
+  in
+  let find_broken_node n =
+    let succs = Node.get_succs n in
+    let preds = Node.get_preds n in
+    match Node.get_kind n with
+    | Node.Start_node _ ->
+        if List.is_empty succs || not (List.is_empty preds) then Error `Other else Ok ()
+    | Node.Exit_node _ ->
+        if not (List.is_empty succs) || List.is_empty preds then Error `Other else Ok ()
+    | Node.Stmt_node _ | Node.Prune_node _ | Node.Skip_node _ ->
+        if List.is_empty succs || List.is_empty preds then Error `Other else Ok ()
+    | Node.Join_node ->
+        (* Join node has the exception that it may be without predecessors
+         and pointing to between_join_and_exit which points to an exit node.
+         This happens when the if branches end with a return.
+         Nested if statements, where all branches have return statements,
+         introduce a sequence of join nodes *)
+        if
+          (List.is_empty preds && not (is_consecutive_join_nodes n NodeSet.empty))
+          || (not (List.is_empty preds) && List.is_empty succs)
+        then Error `Join
+        else Ok ()
+  in
+  (* unconnected nodes generated by Join nodes are expected *)
+  let skip_join_errors current_status node =
+    match find_broken_node node with
+    | Ok () ->
+        Ok current_status
+    | Error `Join ->
+        Ok (Some `Join)
+    | Error _ as other_error ->
+        other_error
+  in
+  match List.fold_result (get_nodes proc_desc) ~init:None ~f:skip_join_errors with
+  | Ok (Some `Join) ->
+      Error `Join
+  | Ok None ->
+      Ok ()
+  | Error _ as error ->
+      error

infer/src/IR/Procdesc.mli

@@ -211,9 +211,8 @@ val pp_local : Format.formatter -> ProcAttributes.var_data -> unit
 
 val is_specialized : t -> bool
 
-(* true if pvar is a captred variable of a cpp lambda or obcj block *)
-
 val is_captured_var : t -> Pvar.t -> bool
+(** true if pvar is a captured variable of a cpp lambda or obcj block *)
 
 val has_modify_in_block_attr : t -> Pvar.t -> bool
 
@@ -229,3 +228,6 @@ val specialize_with_block_args : t -> Typ.Procname.t -> Exp.closure option list
   a) the block parameters are replaces with the closures
   b) the parameters of the method are extended with parameters for the captured variables
   in the closures *)
+
+val is_connected : t -> (unit, [`Join | `Other]) Result.t
+(** checks whether a cfg for the given procdesc is connected or not *)

infer/src/clang/cFrontend_decl.ml

@@ -81,10 +81,10 @@ module CFrontend_decl_funct (T : CModule_type.CTranslation) : CModule_type.CFron
           Procdesc.Node.add_locals_ret_declaration start_node proc_attributes
             (Procdesc.get_locals procdesc) ;
           Procdesc.node_set_succs_exn procdesc start_node meth_body_nodes [] ;
-          match Cfg.proc_cfg_broken_for_node procdesc with
+          match Procdesc.is_connected procdesc with
-          | None ->
+          | Ok () ->
               ()
-          | Some broken_node ->
+          | Error broken_node ->
               let lang =
                 CFrontend_config.string_of_clang_lang trans_unit_ctx.CFrontend_config.lang
               in