EVOLUTION-MANAGER

Edit File: matmul_bcast.h

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

#ifndef TENSORFLOW_CORE_UTIL_MATMUL_BCAST_H_
#define TENSORFLOW_CORE_UTIL_MATMUL_BCAST_H_

#include <vector>

#include "tensorflow/core/framework/tensor_shape.h"
#include "tensorflow/core/lib/gtl/inlined_vector.h"
#include "tensorflow/core/util/bcast.h"

namespace tensorflow {

// Simple wrapper over BCast specialized for MatMul.
// Provides utilities for broadcasting across batch dimensions for binary
// MatMul-like operations.
class MatMulBCast {
 public:
  using Vec = BCast::Vec;

MatMulBCast(Vec x, Vec y);

bool IsValid() const { return batch_bcast_ && batch_bcast_->IsValid(); }
  bool IsBroadcastingRequired() const { return broadcasting_required_; }

const int64 output_batch_size() const { return output_batch_size_; }
  const int64 x_batch_size() const { return x_batch_size_; }
  const int64 y_batch_size() const { return y_batch_size_; }
  const TensorShape& output_batch_shape() const { return output_shape_; }

// Returns the mapping from the flattened output batch indices to x's
  // flattened batch indices. The result is a vector of length
  // output_batch_size(). To compute the i'th batch output, a binary matmul-like
  // operation should use the `x_batch_indices()[i]`th batch index of `x`.
  // Note: Returns an empty vector if broadcasting is not required. Callers
  // should only use this when IsBroadcastingRequired() returns true.
  const std::vector<int64>& x_batch_indices() const { return x_batch_indices_; }
  // Returns the mapping from the flattened output batch indices to y's
  // flattened batch indices. Similar to x_batch_indices().
  // Note: Returns an empty vector if broadcasting is not required. Callers
  // should only use this when IsBroadcastingRequired() returns true.
  const std::vector<int64>& y_batch_indices() const { return y_batch_indices_; }

private:
  std::unique_ptr<BCast> batch_bcast_;
  bool broadcasting_required_ = false;
  int64 x_batch_size_;
  int64 y_batch_size_;
  TensorShape output_shape_;
  int64 output_batch_size_;
  std::vector<int64> x_batch_indices_;
  std::vector<int64> y_batch_indices_;
};

}  // namespace tensorflow

#endif  // TENSORFLOW_CORE_UTIL_MATMUL_BCAST_H_