1 files changed, 40 insertions, 0 deletions
diff --git a/tensorflow/core/kernels/relu_op_functor.h b/tensorflow/core/kernels/relu_op_functor.h
index 633522920c..9577b963c6 100644
--- a/tensorflow/core/kernels/relu_op_functor.h
+++ b/tensorflow/core/kernels/relu_op_functor.h
@@ -125,6 +125,46 @@ struct EluGrad {
   }
 };
 
+// Functor used by SeluOp to do the computations.
+template <typename Device, typename T>
+struct Selu {
+  // Computes Selu activation.
+  //
+  // features: any shape.
+  // activations: same shape as "features".
+  void operator()(const Device& d, typename TTypes<T>::ConstTensor features,
+                  typename TTypes<T>::Tensor activations) {
+    // features.constant(?)
+    const auto scale = static_cast<T>(1.0507009873554804934193349852946);
+    const auto scale_alpha = static_cast<T>(1.7580993408473768599402175208123);
+    const auto one = static_cast<T>(1);
+    const auto zero = static_cast<T>(0);
+    activations.device(d) =
+        (features < zero)
+            .select(scale_alpha * (features.exp() - features.constant(one)),
+                    scale * features);
+  }
+};
+
+// Functor used by SeluGradOp to do the computations.
+template <typename Device, typename T>
+struct SeluGrad {
+  // Computes SeluGrad backprops.
+  //
+  // gradients: gradients backpropagated to the Selu op.
+  // activations: outputs of the Selu op.
+  // backprops: gradients to backpropagate to the Selu inputs.
+  void operator()(const Device& d, typename TTypes<T>::ConstTensor gradients,
+                  typename TTypes<T>::ConstTensor activations,
+                  typename TTypes<T>::Tensor backprops) {
+    const auto scale = static_cast<T>(1.0507009873554804934193349852946);
+    const auto scale_alpha = static_cast<T>(1.7580993408473768599402175208123);
+    backprops.device(d) =
+        (activations < static_cast<T>(0)).select(
+            gradients * (activations + scale_alpha), gradients * scale);
+  }
+};
+
 }  // namespace functor
 }  // namespace tensorflow