[inferbo] Add a model: Object.clone

Reviewed By: ezgicicek

Differential Revision: D18272339

fbshipit-source-id: 6a84a1ac7

infer/src/bufferoverrun/bufferOverrunModels.ml

@@ -1155,6 +1155,15 @@ module ByteBuffer = struct
     {exec; check= no_check}
 end
 
+module Object = struct
+  let clone exp =
+    let exec {integer_type_widths} ~ret:(ret_id, _) mem =
+      let v = Sem.eval integer_type_widths exp mem in
+      model_by_value v ret_id mem
+    in
+    {exec; check= no_check}
+end
+
 module Call = struct
   let dispatch : (Tenv.t, model) ProcnameDispatcher.Call.dispatcher =
     let open ProcnameDispatcher.Call in
@@ -1394,5 +1403,6 @@ module Call = struct
         &:: "getShort" <>$ capt_exp $--> ByteBuffer.get_int
       ; +PatternMatch.implements_nio "ByteBuffer" &:: "getInt" <>$ capt_exp $--> ByteBuffer.get_int
       ; +PatternMatch.implements_nio "ByteBuffer"
-        &:: "getLong" <>$ capt_exp $--> ByteBuffer.get_int ]
+        &:: "getLong" <>$ capt_exp $--> ByteBuffer.get_int
+      ; -"java.lang.Object" &:: "clone" <>$ capt_exp $--> Object.clone ]
 end

infer/tests/codetoanalyze/java/performance/Cost_test.java

@@ -203,3 +203,13 @@ public class Cost_test {
     for (int i = 0; i < get_global(); i++) {}
   }
 }
+
+class CloneTest {
+  int i;
+
+  void clone_test_constant() throws CloneNotSupportedException {
+    this.i = 10;
+    CloneTest o = (CloneTest) this.clone();
+    for (int i = 0; i < o.i; i++) {}
+  }
+}