Create RestartScheduler

Summary:
These changes introduce the RestartScheduler which for now is a copy of the FileScheduler:

- added it as a possible argument to the recently added `--scheduler` option.
- made the necessary changes in `InferAnalyze` to call it if it was chosen.

Reviewed By: ngorogiannis

Differential Revision: D19373505

fbshipit-source-id: 98f065057

infer/man/man1/infer-full.txt

@@ -1690,7 +1690,7 @@ INTERNAL OPTIONS
            Reset the list of folders containing linters definitions to be
            empty (see linters-def-folder).
 
-       --scheduler { File | SyntacticCallGraph }
+       --scheduler { file | restart | callgraph }
            Specify the scheduler used for the analysis phase
 
        --scuba-logging

infer/src/backend/FileScheduler.ml

@@ -15,6 +15,7 @@ let make sources =
   in
   let next x =
     let res = gen.next x in
+    (* see defn of gen above to see why res should never match Some (Procname _) *)
     match res with None -> None | Some (Procname _) -> assert false | Some (File _) as v -> v
   in
   {gen with next}

infer/src/backend/InferAnalyze.ml

@@ -119,10 +119,12 @@ let schedule sources =
     SyntacticCallGraph.make sources )
   else
     match Config.scheduler with
-    | SyntacticCallGraph ->
-        SyntacticCallGraph.make sources
     | File ->
         FileScheduler.make sources
+    | Restart ->
+        RestartScheduler.make sources
+    | SyntacticCallGraph ->
+        SyntacticCallGraph.make sources
 
 
 let analyze source_files_to_analyze =

infer/src/backend/RestartScheduler.ml

@@ -0,0 +1,22 @@
+(*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *)
+open! IStd
+
+(** This behaves exactly the same as the FileScheduler so far. The goal is that it will use a work
+    queue and proc locking to avoid repeating work and hopefully get some in process cache hits. *)
+let make sources =
+  let gen =
+    List.rev_map sources ~f:(fun sf -> SchedulerTypes.File sf)
+    |> List.permute ~random_state:(Random.State.make (Array.create ~len:1 0))
+    |> ProcessPool.TaskGenerator.of_list
+  in
+  let next x =
+    let res = gen.next x in
+    (* see defn of gen above to see why res should never match Some (Procname _) *)
+    match res with None -> None | Some (Procname _) -> assert false | Some (File _) as v -> v
+  in
+  {gen with next}

infer/src/backend/RestartScheduler.mli

@@ -0,0 +1,9 @@
+(*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *)
+open! IStd
+
+val make : SourceFile.t list -> SchedulerTypes.target ProcessPool.TaskGenerator.t

infer/src/base/Config.ml

@@ -92,7 +92,7 @@ type build_system =
   | BXcode
 [@@deriving compare]
 
-type scheduler = File | SyntacticCallGraph [@@deriving equal]
+type scheduler = File | Restart | SyntacticCallGraph [@@deriving equal]
 
 let equal_build_system = [%compare.equal: build_system]
 
@@ -2357,7 +2357,7 @@ and export_changed_functions_output =
 
 and scheduler =
   CLOpt.mk_symbol ~long:"scheduler" ~default:File ~eq:equal_scheduler
-    ~symbols:[("File", File); ("SyntacticCallGraph", SyntacticCallGraph)]
+    ~symbols:[("file", File); ("restart", Restart); ("callgraph", SyntacticCallGraph)]
     "Specify the scheduler used for the analysis phase"
 
 

infer/src/base/Config.mli

@@ -25,7 +25,7 @@ type build_system =
   | BNdk
   | BXcode
 
-type scheduler = File | SyntacticCallGraph [@@deriving equal]
+type scheduler = File | Restart | SyntacticCallGraph [@@deriving equal]
 
 val equal_build_system : build_system -> build_system -> bool