torch.mutation
==================
user_input_mutation
^^^^^^^^^^^^^^^^^^^

.. note::

    Tags: :doc:`torch.mutation <torch.mutation>`

    Support Level: SUPPORTED

Original source code:

.. code-block:: python

    # mypy: allow-untyped-defs
    import torch
    
    
    class UserInputMutation(torch.nn.Module):
        """
        Directly mutate user input in forward
        """
    
        def forward(self, x):
            x.mul_(2)
            return x.cos()
    
    
    example_args = (torch.randn(3, 2),)
    tags = {"torch.mutation"}
    model = UserInputMutation()
    

    torch.export.export(model, example_args)

Result:

.. code-block::

    ExportedProgram:
        class GraphModule(torch.nn.Module):
            def forward(self, x: "f32[3, 2]"):
                     mul_: "f32[3, 2]" = torch.ops.aten.mul_.Tensor(x, 2);  x = None
                
                     cos: "f32[3, 2]" = torch.ops.aten.cos.default(mul_);  mul_ = None
                return (cos,)
                
    Graph signature: 
        # inputs
        x: USER_INPUT
        
        # outputs
        cos: USER_OUTPUT
        
    Range constraints: {}