LSTM cell fused operator.

src/ngraph/CMakeLists.txt

@@ -302,12 +302,16 @@ set (SRC
     op/fused/grn.hpp
     op/fused/group_conv.hpp
     op/fused/group_conv.cpp
+    op/fused/lstm_cell.cpp
+    op/fused/lstm_cell.hpp
     op/fused/mvn.cpp
     op/fused/mvn.hpp
     op/fused/normalize.cpp
     op/fused/normalize.hpp
     op/fused/prelu.cpp
     op/fused/prelu.hpp
+    op/fused/rnn_cell_base.cpp
+    op/fused/rnn_cell_base.hpp
     op/fused/scale_shift.cpp
     op/fused/scale_shift.hpp
     op/fused/space_to_depth.cpp
@@ -320,6 +324,8 @@ set (SRC
     op/fused/squeeze.hpp
     op/fused/unsqueeze.cpp
     op/fused/unsqueeze.hpp
+    op/util/activation_functions.cpp
+    op/util/activation_functions.hpp
     op/util/arithmetic_reduction.cpp
     op/util/arithmetic_reduction.hpp
     op/util/binary_elementwise_arithmetic.cpp

src/ngraph/frontend/onnx_import/CMakeLists.txt

@@ -189,8 +189,6 @@ add_library(onnx_import STATIC
         utils/reduction.hpp
         utils/reshape.cpp
         utils/reshape.hpp
-        utils/rnn/activation_functions.cpp
-        utils/rnn/activation_functions.hpp
         utils/variadic.hpp)
 
 set(ONNX_IMPORT_INCLUDE_DIR ${CMAKE_CURRENT_SOURCE_DIR} CACHE INTERNAL "")

src/ngraph/ngraph.hpp

@@ -103,6 +103,7 @@
 #include "ngraph/op/fused/grn.hpp"
 #include "ngraph/op/fused/group_conv.hpp"
 #include "ngraph/op/fused/hard_sigmoid.hpp"
+#include "ngraph/op/fused/lstm_cell.hpp"
 #include "ngraph/op/fused/mvn.hpp"
 #include "ngraph/op/fused/normalize.hpp"
 #include "ngraph/op/fused/prelu.hpp"

src/ngraph/op/fused_op_tbl.hpp

@@ -27,6 +27,7 @@ NGRAPH_OP(GRN, ngraph::op)
 NGRAPH_OP(Gemm, ngraph::op)
 NGRAPH_OP(GroupConvolution, ngraph::op)
 NGRAPH_OP(HardSigmoid, ngraph::op)
+NGRAPH_OP(LSTMCell, ngraph::op)
 NGRAPH_OP(MVN, ngraph::op)
 NGRAPH_OP(Normalize, ngraph::op)
 NGRAPH_OP(PRelu, ngraph::op)

src/ngraph/serializer.cpp

@@ -74,6 +74,7 @@
 #include "ngraph/op/fused/grn.hpp"
 #include "ngraph/op/fused/group_conv.hpp"
 #include "ngraph/op/fused/hard_sigmoid.hpp"
+#include "ngraph/op/fused/lstm_cell.hpp"
 #include "ngraph/op/fused/mvn.hpp"
 #include "ngraph/op/fused/normalize.hpp"
 #include "ngraph/op/fused/prelu.hpp"
@@ -1055,6 +1056,29 @@ static shared_ptr<ngraph::Function>
                 node = make_shared<op::LRN>(args[0], alpha, beta, bias, nsize);
                 break;
             }
+            case OP_TYPEID::LSTMCell:
+            {
+                auto hidden_size = node_js.at("hidden_size").get<size_t>();
+                auto clip = node_js.at("clip").get<float>();
+                auto activations = node_js.at("activations").get<vector<string>>();
+                auto activation_alpha = node_js.at("activation_alpha").get<vector<float>>();
+                auto activation_beta = node_js.at("activation_beta").get<vector<float>>();
+                auto input_forget = node_js.at("input_forget").get<bool>();
+                node = make_shared<op::LSTMCell>(args[0],
+                                                 args[1],
+                                                 args[2],
+                                                 args[3],
+                                                 args[4],
+                                                 hidden_size,
+                                                 args[5],
+                                                 args[6],
+                                                 activations,
+                                                 activation_alpha,
+                                                 activation_beta,
+                                                 clip,
+                                                 input_forget);
+                break;
+            }
             case OP_TYPEID::Max:
             {
                 auto reduction_axes = node_js.at("reduction_axes").get<set<size_t>>();
@@ -1979,6 +2003,17 @@ static json write(const Node& n, bool binary_constant_data)
         node["nsize"] = tmp->get_nsize();
         break;
     }
+    case OP_TYPEID::LSTMCell:
+    {
+        auto tmp = dynamic_cast<const op::LSTMCell*>(&n);
+        node["hidden_size"] = tmp->get_hidden_size();
+        node["clip"] = tmp->get_clip();
+        node["activations"] = tmp->get_activations();
+        node["activation_alpha"] = tmp->get_activation_alpha();
+        node["activation_beta"] = tmp->get_activation_beta();
+        node["input_forget"] = tmp->get_input_forget();
+        break;
+    }
     case OP_TYPEID::Max:
     {
         auto tmp = dynamic_cast<const op::Max*>(&n);