[dynamo] Fix handling of kwargs in exception constructor (#163390)

Pull Request resolved: https://github.com/pytorch/pytorch/pull/163390
Approved by: https://github.com/guilhermeleobas

test/dynamo/test_exceptions.py

@@ -10,6 +10,7 @@ import torch._functorch.config
 import torch.nn
 import torch.utils.checkpoint
 from torch._dynamo.bytecode_transformation import Instruction
+from torch._dynamo.exc import Unsupported
 from torch._dynamo.symbolic_convert import SpeculationLog, SpeculationLogDivergence
 from torch.testing._internal.common_utils import (
     instantiate_parametrized_tests,
@@ -934,6 +935,13 @@ class ExceptionTests(torch._dynamo.test_case.TestCase):
 
         assert exc2.__context__ is None
 
+    def test_exception_kwargs(self):
+        @torch.compile(backend="eager", fullgraph=True)
+        def fn():
+            raise AttributeError(name="a")
+
+        self.assertRaises(Unsupported, fn)
+
 
 instantiate_parametrized_tests(ExceptionTests)
 

torch/_dynamo/graph_break_registry.json

@@ -2726,5 +2726,15 @@
       "Explanation": "Object does not allow us to make a weakref to it",
       "Hints": []
     }
+  ],
+  "GB0273": [
+    {
+      "Gb_type": "Keyword args passed to exception constructor",
+      "Context": "{self} with kwargs {init_kwargs}",
+      "Explanation": "Dynamo does not know how to handle keyword args passed to an exception constructor",
+      "Hints": [
+        "It may be possible to write Dynamo tracing rules for this code. Please report an issue to PyTorch if you encounter this graph break often and it is causing performance issues."
+      ]
+    }
   ]
 }

torch/_dynamo/variables/builtin.py

@@ -989,7 +989,7 @@ class BuiltinVariable(VariableTracker):
                         hints=[*graph_break_hints.SUPPORTABLE],
                     )
 
-                return variables.ExceptionVariable(fn, args, **kwargs)
+                return variables.ExceptionVariable(fn, args, kwargs)
 
             return create_exception_class_object
 

torch/_dynamo/variables/misc.py

@@ -388,10 +388,19 @@ class SuperVariable(VariableTracker):
 
 class ExceptionVariable(VariableTracker):
     # The ExceptionVariable corresponds to the BaseException class in Python
-    def __init__(self, exc_type, args, **kwargs) -> None:
-        super().__init__(**kwargs)
+    def __init__(
+        self, exc_type, args, init_kwargs=None, source=None, mutation_type=None
+    ) -> None:
+        super().__init__(source=source, mutation_type=mutation_type)
         self.exc_type = exc_type
         self.args = args
+        if init_kwargs:
+            unimplemented_v2(
+                gb_type="Keyword args passed to exception constructor",
+                context=f"{self} with kwargs {init_kwargs}",
+                explanation="Dynamo does not know how to handle keyword args passed to an exception constructor",
+                hints=[*graph_break_hints.SUPPORTABLE],
+            )
         # When raising a new exception while another exception is already being
         # handled, the new exception's __context__ attribute is automatically
         # set to the handled exception.