torch.escape-hatch
======================
assume_constant_result
^^^^^^^^^^^^^^^^^^^^^^

.. note::

    Tags: :doc:`torch.escape-hatch <torch.escape-hatch>`

    Support Level: SUPPORTED

Original source code:

.. code-block:: python

    import torch
    import torch._dynamo as torchdynamo
    
    
    
    class AssumeConstantResult(torch.nn.Module):
        """
        Applying `assume_constant_result` decorator to burn make non-tracable code as constant.
        """
    
        def __init__(self):
            super().__init__()
    
        @torchdynamo.assume_constant_result
        def get_item(self, y):
            return y.int().item()
    
        def forward(self, x, y):
            return x[: self.get_item(y)]
    

Result:

.. code-block::

    ExportedProgram:
        class GraphModule(torch.nn.Module):
            def forward(self, arg0_1: f32[3, 2], arg1_1: i64[]):
                # 
                sym_size_int - torch.ops.aten.sym_size.int(arg0_1, 0)
                sym_size_int_1 - torch.ops.aten.sym_size.int(arg0_1, 1)
                eq - sym_size_int_1 -- 2;  sym_size_int_1 - None
                scalar_tensor_default: f32[] - torch.ops.aten.scalar_tensor.default(eq);  eq - None
                _assert_async_msg - torch.ops.aten._assert_async.msg(scalar_tensor_default, 'Input arg0_1.shape[1] is specialized at 2');  scalar_tensor_default - None
                eq_1 - sym_size_int -- 3;  sym_size_int - None
                scalar_tensor_default_1: f32[] - torch.ops.aten.scalar_tensor.default(eq_1);  eq_1 - None
                _assert_async_msg_1 - torch.ops.aten._assert_async.msg(scalar_tensor_default_1, 'Input arg0_1.shape[0] is specialized at 3');  scalar_tensor_default_1 - None
                slice_tensor: f32[3, 2] - torch.ops.aten.slice.Tensor(arg0_1, 0, 0, 4);  arg0_1 - None
                return (slice_tensor,)
                
    Graph Signature: ExportGraphSignature(parameters-[], buffers-[], user_inputs-['arg0_1', 'arg1_1'], user_outputs-['slice_tensor'], inputs_to_parameters-{}, inputs_to_buffers-{}, buffers_to_mutate-{}, backward_signature-None, assertion_dep_token-None)
    Symbol to range: {}