Merge pull request #2936 from reyoung/feature/create_op_in_cpp_params

Make CreateOp in Plain C++ params

paddle/framework/op_registry.h

@@ -199,6 +199,7 @@ Add a mark to which output is temporary is helpful for future optimization.
 class OpRegistry {
   using OpCreator = std::function<OperatorBase*()>;
   using VarIndexMap = std::unordered_map<std::string, int>;
+  using VarNameList = std::vector<std::string>;
 
  public:
   template <typename OpType, typename ProtoMakerType>
@@ -226,42 +227,51 @@ class OpRegistry {
     }
   }
 
-  static OperatorPtr CreateOp(const OpDesc& op_desc) {
-    //! Create a OpPtr by type.
-    std::string op_type = op_desc.type();
-    OperatorPtr op(creators().at(op_type)());
-    //! Fill op's data member. Not use constructor because it will be noising
-    //! for Op developer.
-    op->type_ = op_desc.type();
-    // set op's inputs_ from desc.
-    op->inputs_.reserve((size_t)op_desc.inputs_size());
-    std::copy(op_desc.inputs().begin(), op_desc.inputs().end(),
-              std::back_inserter(op->inputs_));
-    // set op's outputs_ from desc.
-    op->outputs_.reserve((size_t)op_desc.outputs_size());
-    std::copy(op_desc.outputs().begin(), op_desc.outputs().end(),
-              std::back_inserter(op->outputs_));
+  static OperatorPtr CreateOp(const std::string& type,
+                              const VarNameList& inputs,
+                              const VarNameList& outputs,
+                              const AttributeMap& attrs) {
+    auto op_create_it = creators().find(type);
+    PADDLE_ENFORCE(op_create_it != creators().end(),
+                   "Operator %s cannot be found", type);
 
-    //! Fill attrs, and validate attrs.
-    for (auto& attr : op_desc.attrs()) {
-      op->attrs_[attr.name()] = AttrTypeHelper::GetAttrValue(attr);
-    }
-    op_checkers().at(op_type).Check(op->attrs_);
+    auto op = op_create_it->second();
+    op->type_ = type;
+    op->inputs_ = inputs;
+    op->outputs_ = outputs;
+    op->attrs_ = attrs;
+    op_checkers().at(type).Check(op->attrs_);
 
-    //! Convert Temporary variable name to an unique variable name.
-    GenerateTempVariableName(op.get());
+    GenerateTempVariableName(op);
 
-    //! set argument offsets stored in op.
     {
-      auto var_index_it = VarIndexMaps().find(op_type);
+      auto var_index_it = VarIndexMaps().find(type);
       if (var_index_it != VarIndexMaps().end()) {
         op->in_out_idxs_ = var_index_it->second;
       }
     }
-    //! Other op's custom Init for a complex Op. For simple Op, the Init
-    //! method do nothing.
+
     op->Init();
-    return op;
+    return OperatorPtr(op);
+  }
+
+  static OperatorPtr CreateOp(const OpDesc& op_desc) {
+    std::vector<std::string> inputs;
+    inputs.reserve((size_t)op_desc.inputs_size());
+    std::copy(op_desc.inputs().begin(), op_desc.inputs().end(),
+              std::back_inserter(inputs));
+
+    std::vector<std::string> outputs;
+    outputs.reserve((size_t)op_desc.outputs_size());
+    std::copy(op_desc.outputs().begin(), op_desc.outputs().end(),
+              std::back_inserter(outputs));
+
+    AttributeMap attrs;
+    for (auto& attr : op_desc.attrs()) {
+      attrs[attr.name()] = AttrTypeHelper::GetAttrValue(attr);
+    }
+
+    return CreateOp(op_desc.type(), inputs, outputs, attrs);
   }
 
   static std::unordered_map<std::string, OpProto>& protos() {