fix a bug related to activation functions

src/onnx/onnx.cpp

@@ -31,7 +31,7 @@ struct onnx_parser
     bool is_pytorch = false;
 
     std::unordered_map<std::string, op_func> ops;
-    std::unordered_map<std::string, operation> actv_funcs;
+    std::unordered_map<std::string, operation> map_actv_funcs;
 
     onnx_parser()
     {
@@ -94,11 +94,11 @@ struct onnx_parser
 
     void init_actv_func()
     {
-        actv_funcs.insert(std::make_pair("tanh", op::tanh{}));
-        actv_funcs.insert(std::make_pair("relu", op::relu{}));
-        actv_funcs.insert(std::make_pair("sigmoid", op::sigmoid{}));
-        actv_funcs.insert(std::make_pair("leakyrelu", op::leaky_relu{}));
-        actv_funcs.insert(std::make_pair("elu", op::elu{}));
+        map_actv_funcs.insert(std::make_pair("tanh", op::tanh{}));
+        map_actv_funcs.insert(std::make_pair("relu", op::relu{}));
+        map_actv_funcs.insert(std::make_pair("sigmoid", op::sigmoid{}));
+        map_actv_funcs.insert(std::make_pair("leakyrelu", op::leaky_relu{}));
+        map_actv_funcs.insert(std::make_pair("elu", op::elu{}));
     }
 
     template <class F>
@@ -669,7 +669,7 @@ struct onnx_parser
             activation_func = attributes.at("activations").strings(0);
         }
 
-        if(actv_funcs.count(activation_func) == 0)
+        if(map_actv_funcs.count(activation_func) == 0)
         {
             MIGRAPHX_THROW("RNN: activation function " + activation_func + " not supported");
         }
@@ -698,7 +698,7 @@ struct onnx_parser
             clip = parse_value(attributes.at("clip")).at<float>();
         }
 
-        return prog.add_instruction(op::rnn{hidden_size, actv_funcs[activation_func], dirct, clip},
+        return prog.add_instruction(op::rnn{hidden_size, map_actv_funcs[activation_func], dirct, clip},
                                     std::move(args));
     }
 
@@ -734,25 +734,62 @@ struct onnx_parser
             dirct = op::gru::reverse;
         }
 
-        std::vector<std::string> act_funcs = {"sigmoid", "tanh"};
+        std::vector<std::string> actv_func_names = {"sigmoid", "tanh"};
         if(contains(attributes, "activations"))
         {
-            act_funcs[0] = attributes.at("activations").strings(0);
-            act_funcs[1] = attributes.at("activations").strings(1);
+            auto names = attributes.at("activations").strings();
+            actv_func_names.clear();
+            for (auto &fn : names)
+            {
+                actv_func_names.push_back(fn);
+            }
         }
 
-        if(act_funcs.size() != 2)
+        if(actv_func_names.size() != 2)
         {
             MIGRAPHX_THROW("GRU: wrong activation function attribute");
         }
 
-        for(std::size_t i = 0; i < act_funcs.size(); ++i)
+        // need 4 activation functions
+        if (dirct == op::gru::bidirectional)
+        {
+            // one name is provided, need to repeat the function 3 times
+            if (actv_func_names.size() == 1)
+            {
+                actv_func_names.resize(4, actv_func_names.at(0));
+            }
+            else if (actv_func_names.size() == 2)
             {
-            if(actv_funcs.count(act_funcs.at(i)) == 0)
+                actv_func_names.insert(actv_func_names.end(), actv_func_names.begin(), actv_func_names.end());
+            }
+            else if (actv_func_names.size() == 3)
             {
-                MIGRAPHX_THROW("GRU: activation function " + act_funcs.at(i) + " not supported");
+                MIGRAPHX_THROW("GRU: birectional network cannot have 3 activation functions in attribute");
+            }
         }
+        else 
+        {
+            if (actv_func_names.size() == 1)
+            {
+                actv_func_names.push_back(actv_func_names.at(0));
             }
+        }
+
+        for_each(actv_func_names.begin(), actv_func_names.end(), 
+            [&](auto &name) 
+            { 
+                if (map_actv_funcs.count(name) == 0)
+                {
+                    MIGRAPHX_THROW("GRU: activation function " + name + " not supported");
+                } 
+            });
+
+        std::vector<operation> vec_actv_funcs;
+        for_each(actv_func_names.begin(), actv_func_names.end(), 
+            [&](auto &name) 
+            { 
+                vec_actv_funcs.push_back(map_actv_funcs[name]); 
+            });
 
         // To be added later
         float clip = 0.0;
@@ -769,7 +806,7 @@ struct onnx_parser
 
         return prog.add_instruction(
             op::gru{hidden_size,
-                    {actv_funcs[act_funcs.at(0)], actv_funcs[act_funcs.at(1)]},
+                    vec_actv_funcs,
                     dirct,
                     clip,
                     linear_before_reset},