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Author: Yang Yang

paddle/fluid/framework/operator.cc

@@ -180,6 +180,15 @@ OperatorBase::OperatorBase(const std::string& type,
   CheckAllInputOutputSet();
 }
 
+std::vector<std::string> OperatorBase::InputVars() const {
+  std::vector<std::string> ret_val;
+  for (auto& o : inputs_) {
+    ret_val.reserve(ret_val.size() + o.second.size());
+    ret_val.insert(ret_val.end(), o.second.begin(), o.second.end());
+  }
+  return ret_val;
+}
+
 std::vector<std::string> OperatorBase::OutputVars(bool has_intermediate) const {
   std::vector<std::string> ret_val;
   if (has_intermediate) {

paddle/fluid/framework/operator.h

@@ -109,13 +109,15 @@ class OperatorBase {
   std::string Input(const std::string& name) const;
   //! Get a input which has multiple variables.
   const std::vector<std::string>& Inputs(const std::string& name) const;
+  //! Get all inputs variable names
+  std::vector<std::string> InputVars() const;
 
   //! Get a output with argument's name described in `op_proto`
   std::string Output(const std::string& name) const;
   //! Get an output which has multiple variables.
   //! TODO add a vector_view to prevent memory copy.
   const std::vector<std::string>& Outputs(const std::string& name) const;
-
+  //! Get all outputs variable names
   virtual std::vector<std::string> OutputVars(bool has_intermediate) const;
 
   // Return a new operator instance, which is as same as this.

paddle/fluid/pybind/pybind.cc

@@ -402,6 +402,7 @@ All parameter, weight, gradient are variables in Paddle.
       .def("output_vars",
            [](const OperatorBase &op) { return op.OutputVars(true); })
       .def("inputs", [](const OperatorBase &op) { return op.Inputs(); })
+      .def("input_vars", [](const OperatorBase &op) { return op.InputVars(); })
       .def("__str__", &OperatorBase::DebugString)
       .def("no_intermediate_outputs",
            [](const OperatorBase &op) { return op.OutputVars(false); })