Add test cases.

com.ibm.wala.cast.python.ml.test/source/com/ibm/wala/cast/python/ml/test/TestTensorflow2Model.java

@@ -3139,6 +3139,26 @@ public void testReshape3() throws ClassHierarchyException, CancelException, IOEx
     test("tf2_test_reshape3.py", "f", 1, 1, 2);
   }
 
+  @Test
+  public void testCalls() throws ClassHierarchyException, CancelException, IOException {
+    test(
+        new String[] {"tf2_test_calls.py", "tf2_test_calls2.py", "tf2_test_calls3.py"},
+        "tf2_test_calls.py",
+        "C.call",
+        "",
+        1,
+        1,
+        3);
+    test(
+        new String[] {"tf2_test_calls.py", "tf2_test_calls2.py", "tf2_test_calls3.py"},
+        "tf2_test_calls2.py",
+        "C.call",
+        "",
+        1,
+        1,
+        3);
+  }
+
   private void test(
       String filename,
       String functionName,

com.ibm.wala.cast.python.test/data/tf2_test_calls.py

@@ -0,0 +1,11 @@
+import tensorflow as tf
+from tf2_test_calls3 import g
+
+
+class C(tf.keras.Model):
+
+    def call(self, a):
+        assert isinstance(a, tf.Tensor)
+
+
+g(C())

com.ibm.wala.cast.python.test/data/tf2_test_calls2.py

@@ -0,0 +1,11 @@
+import tensorflow as tf
+from tf2_test_calls3 import g
+
+
+class C(tf.keras.Model):
+
+    def call(self, a):
+        assert isinstance(a, tf.Tensor)
+
+
+g(C())

com.ibm.wala.cast.python.test/data/tf2_test_calls3.py

@@ -0,0 +1,5 @@
+import tensorflow as tf
+
+
+def g(b):
+    b(tf.constant(1))

com.ibm.wala.cast.python/source/com/ibm/wala/cast/python/ipa/callgraph/PythonInstanceMethodTrampolineTargetSelector.java

@@ -222,6 +222,8 @@ private IClass getCallable(CGNode caller, IClassHierarchy cha, PythonInvokeInstr
     PointerKey receiver = pkf.getPointerKeyForLocal(caller, call.getUse(0));
     OrdinalSet<InstanceKey> objs = builder.getPointerAnalysis().getPointsToSet(receiver);
 
+    LOGGER.fine(() -> receiver + " points to " + objs.size() + " instance(s).");
+
     for (InstanceKey o : objs) {
       AllocationSiteInNode instanceKey = getAllocationSiteInNode(o);
       if (instanceKey != null) {