[starvation] ignore local/temp variables as locks

Reviewed By: sblackshear

Differential Revision: D7420069

fbshipit-source-id: caea591

infer/src/concurrency/starvation.ml

@@ -27,13 +27,23 @@ module TransferFunctions (CFG : ProcCfg.S) = struct
   module CFG = CFG
   module Domain = StarvationDomain
 
-  type extras = ProcData.no_extras
+  type extras = FormalMap.t
 
-  let exec_instr (astate: Domain.astate) {ProcData.pdesc} _ (instr: HilInstr.t) =
+  let exec_instr (astate: Domain.astate) {ProcData.pdesc; extras} _ (instr: HilInstr.t) =
     let open RacerDConfig in
+    let is_formal base = FormalMap.is_formal base extras in
     let get_path actuals =
-      List.hd actuals |> Option.value_map ~default:[] ~f:HilExp.get_access_exprs |> List.hd
+      match actuals with
-      |> Option.map ~f:AccessExpression.to_access_path
+      | (HilExp.AccessExpression access_exp) :: _ -> (
+        match AccessExpression.to_access_path access_exp with
+        | (((Var.ProgramVar pvar, _) as base), _) as path
+          when is_formal base || Pvar.is_global pvar ->
+            Some path
+        | _ ->
+            (* ignore paths on local or logical variables *)
+            None )
+      | _ ->
+          None
     in
     match instr with
     | Call (_, Direct callee_pname, actuals, _, loc) -> (
@@ -154,7 +164,8 @@ let report_deadlocks get_proc_desc tenv pdesc summary =
 
 
 let analyze_procedure {Callbacks.proc_desc; get_proc_desc; tenv; summary} =
-  let proc_data = ProcData.make_default proc_desc tenv in
+  let formals = FormalMap.make proc_desc in
+  let proc_data = ProcData.make proc_desc tenv formals in
   let initial =
     if not (Procdesc.is_java_synchronized proc_desc) then StarvationDomain.empty
     else

infer/tests/codetoanalyze/java/starvation/LocalLock.java

@@ -0,0 +1,32 @@
+/*
+ * Copyright (c) 2018 - present Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+class LocalLock {
+  Object lock1, lock2;
+
+  Object get_lock1() {
+    return lock1;
+  }
+
+  void local_lock_outer_ok() {
+    synchronized(get_lock1()) {
+      synchronized(this) {}
+    }
+  }
+
+  Object get_lock2() {
+    return lock2;
+  }
+
+  void local_lock_inner_ok() {
+    synchronized(this) {
+      synchronized(get_lock2()) {}
+    }
+  }
+}