Add hasattr for tensor variable (pytorch#131008)

Pull Request resolved: pytorch#131008
Approved by: https://github.com/anijain2305
ghstack dependencies: pytorch#131007

test/dynamo/test_misc.py

@@ -1364,6 +1364,20 @@ def fn(x):
         r2 = opt_fn(i)
         self.assertEqual(r1, r2)
 
+    def test_tensor_hasattr(self):
+        @torch.compile(fullgraph=True)
+        def fn(x):
+            if hasattr(x, "test"):
+                return x + 2
+            else:
+                return x + 1
+
+        self.assertEqual(torch.ones(2, 2) + 1, fn(torch.ones(2, 2)))
+
+        inp = torch.ones(2, 2)
+        inp.test = None
+        self.assertEqual(torch.ones(2, 2) + 2, fn(inp))
+
     def test_shape_unpack(self):
         def fn(x):
             a, b = x.size()

torch/_dynamo/variables/tensor.py

@@ -333,6 +333,27 @@ def method_attr__version(self, tx):
             tx, [self], {}
         )
 
+    def call_hasattr(self, tx, name):
+        from . import GetAttrVariable
+        from .builtin import BuiltinVariable
+
+        try:
+            var = BuiltinVariable(getattr).call_function(
+                tx, [self, ConstantVariable(name)], {}
+            )
+            # in the event that TensorVariable returns NotImplemented
+            # BuiltinVariable.call_getattr returns GetAttrVariable
+            ret_val = not isinstance(var, GetAttrVariable)
+        except AttributeError:
+            ret_val = False
+
+        if self.source:
+            install_guard(
+                AttrSource(self.source, name).make_guard(GuardBuilder.HASATTR)
+            )
+
+        return ConstantVariable(ret_val)
+
     def var_getattr(self, tx, name):
         from . import UserDefinedClassVariable