Registers a backward pre-hook common to all the modules.
This adds global state to the nn.module module and it is only intended for debugging/profiling purposes.
The hook will be called every time the gradients for the module are computed. The hook should have the following signature:
hook(module, grad_output) -> Tensor or None
grad_outputis a tuple. The hook should not modify its arguments, but it can optionally return a new gradient with respect to the output that will be used in place of
grad_outputin subsequent computations. Entries in
Nonefor all non-Tensor arguments.
For technical reasons, when this hook is applied to a Module, its forward function will receive a view of each Tensor passed to the Module. Similarly the caller will receive a view of each Tensor returned by the Module’s forward function.
Global hooks are called before hooks registered with register_backward_pre_hook
a handle that can be used to remove the added hook by calling
- Return type