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diff --git a/tensorflow/core/kernels/softsign_op.h b/tensorflow/core/kernels/softsign_op.h
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+/* Copyright 2015 Google Inc. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+==============================================================================*/
+
+#ifndef TENSORFLOW_KERNELS_SOFTSIGN_OP_H_
+#define TENSORFLOW_KERNELS_SOFTSIGN_OP_H_
+// Functor definition for SoftsignOp and SoftsignGradOp, must be compilable by
+// nvcc.
+
+#include "third_party/eigen3/unsupported/Eigen/CXX11/Tensor"
+#include "tensorflow/core/framework/tensor_types.h"
+
+namespace tensorflow {
+namespace functor {
+
+// Functor used by SoftsignOp to do the computations.
+template <typename Device, typename T>
+struct Softsign {
+  // Computes Softsign activation.
+  //
+  // features: any shape.
+  // activations: same shape as "features".
+  void operator()(const Device& d, typename TTypes<T>::ConstTensor features,
+                  typename TTypes<T>::Tensor activations) {
+    activations.device(d) =
+        features / (features.abs() + features.constant(1.0f));
+  }
+};
+
+// Functor used by SoftsignGradOp to do the computations.
+template <typename Device, typename T>
+struct SoftsignGrad {
+  // Computes SoftsignGrad backprops.
+  //
+  // gradients: gradients backpropagated to the Softsign op.
+  // features: inputs that were passed to the Softsign op.
+  // backprops: gradients to backpropagate to the Softsign inputs.
+  void operator()(const Device& d, typename TTypes<T>::ConstTensor gradients,
+                  typename TTypes<T>::ConstTensor features,
+                  typename TTypes<T>::Tensor backprops) {
+    backprops.device(d) =
+        gradients / (features.abs() + features.constant(1.0f)).square();
+  }
+};
+
+}  // namespace functor
+}  // namespace tensorflow
+
+#endif  // TENSORFLOW_KERNELS_SOFTSIGN_OP_H_