EVOLUTION-MANAGER

Edit File: while_gradients.h

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==============================================================================*/

#ifndef TENSORFLOW_CC_FRAMEWORK_WHILE_GRADIENTS_H_
#define TENSORFLOW_CC_FRAMEWORK_WHILE_GRADIENTS_H_

#include "tensorflow/cc/framework/ops.h"
#include "tensorflow/cc/framework/scope.h"
#include "tensorflow/core/graph/while_context.h"

// Utility functions for constructing while loop gradients

namespace tensorflow {

// Adds the gradient computation for the while loop associated with
// `while_ctx`. `grad_inputs` are the partial derivatives w.r.t. the loop
// outputs, i.e. the exit nodes.  The partial derivatives w.r.t. the loop
// inputs, i.e. the input loop vars, are returned in `grad_outputs`.
// `grad_inputs` and `grad_outputs` are both in loop-variable order, as defined
// by the original inputs to BuildWhileLoop().
// TODO(skyewm): maybe comment on NoGradient once it's supported
Status AddWhileLoopGradient(WhileContext* while_ctx, const Scope& scope,
                            const std::vector<Output>& grad_inputs,
                            std::vector<Output>* grad_outputs);

}  // namespace tensorflow

#endif  // TENSORFLOW_CC_FRAMEWORK_WHILE_GRADIENTS_H_