The @NoAllocation checker should not report on created exceptions

Summary:public
The NoAllocation checker should not report on the creation of exceptions

Reviewed By: sblackshear

Differential Revision: D2969719

fb-gh-sync-id: 4a8ffc8
shipit-source-id: 4a8ffc8

infer/src/checkers/performanceCritical.ml

@@ -125,13 +125,23 @@ let method_calls_expensive tenv pname =
   || calls_expensive ()
 
 
-let method_allocates pname =
+let is_allocator tenv pname =
+  let is_exception () =
+    let class_name =
+      Typename.Java.from_string (Procname.java_get_class pname) in
+    AndroidFramework.is_exception tenv class_name in
+  Procname.is_constructor pname
+  && not (SymExec.function_is_builtin pname)
+  && not (is_exception ())
+
+
+let method_allocates tenv pname =
   let allocates () =
     match lookup_call_summary pname with
     | Some { Specs.allocations } ->
         allocations <> []
     | None -> false in
-  Procname.is_constructor pname
+  is_allocator tenv pname
   || allocates ()
 
 
@@ -154,7 +164,7 @@ let collect_calls tenv caller_pdesc checked_pnames call_summary (pname, _) =
         else
           call_summary.Specs.expensive_calls in
       let updated_allocations =
-        if method_allocates pname then
+        if method_allocates tenv pname then
           (pname, call_loc) :: call_summary.Specs.allocations
         else
           call_summary.Specs.allocations in
@@ -179,6 +189,7 @@ let update_summary call_summary pname =
 let string_of_pname =
   Procname.to_simplified_string ~withclass:true
 
+
 let update_trace trace loc =
   if Location.equal loc Location.dummy then trace
   else

infer/src/harness/androidFramework.ml

@@ -373,15 +373,26 @@ let get_lifecycle_for_framework_typ_opt lifecycle_typ lifecycle_proc_strs tenv =
 let get_lifecycles = android_lifecycles
 
 
-(** Checks if the exception is an uncheched exception *)
-let is_runtime_exception tenv exn =
+let is_subclass tenv cn1 cn2 =
   let lookup = Sil.tenv_lookup tenv in
+  match lookup cn1, lookup cn2 with
+  | Some typ1, Some typ2 ->
+      is_subtype typ1 typ2 tenv
+  | _ -> false
+
+
+(** Checks if the exception is an uncheched exception *)
+let is_runtime_exception tenv typename =
   let runtime_exception_typename =
     Typename.Java.from_string "java.lang.RuntimeException" in
-  match lookup runtime_exception_typename, lookup exn with
-  | Some runtime_exception_type, Some exn_type ->
-      is_subtype exn_type runtime_exception_type tenv
-  | _ -> false
+  is_subclass tenv typename runtime_exception_typename
+
+
+(** Checks if the class name is a Java exception *)
+let is_exception tenv typename =
+  let exception_typename =
+    Typename.Java.from_string "java.lang.Exception" in
+  is_subclass tenv typename exception_typename
 
 
 let non_stub_android_jar () =

infer/src/harness/androidFramework.mli

@@ -52,5 +52,8 @@ val is_android_lib_class : Typename.t -> bool
 (** Path to the android.jar file containing real code, not just the method stubs as in the SDK *)
 val non_stub_android_jar : unit -> string
 
+(** [is_exception tenv class_name] checks if class_name is a Java exception *)
+val is_exception : Sil.tenv -> Typename.t -> bool
+
 (** [is_runtime_exception tenv exn] checks if exn is an unchecked exception *)
 val is_runtime_exception : Sil.tenv -> Typename.t -> bool

infer/tests/codetoanalyze/java/checkers/NoAllocationExample.java

@@ -40,4 +40,14 @@ public class NoAllocationExample {
     new Object();
   }
 
+  @NoAllocation
+  void throwsException() {
+    throw new RuntimeException();
+  }
+
+  @NoAllocation
+  void creatingExceptionIsFine() {
+    throwsException();
+  }
+
 }