use function instead of lambda, test=develop (#22348)

* use function instead of lambda, test=develop

* follow comments, test=develop

paddle/fluid/pybind/op_function_generator.cc

@@ -23,45 +23,46 @@
 #include "paddle/fluid/pybind/pybind.h"
 #include "paddle/fluid/string/string_helper.h"
 
+// clang-format off
 const char* OUT_INITIALIZER_TEMPLATE =
     R"({"%s", {std::shared_ptr<imperative::VarBase>(new imperative::VarBase(tracer->GenerateUniqueName()))}})";
 
 const char* OP_FUNCTION_TEMPLATE =
-    R"([](const imperative::NameVarBaseMap& ins, const framework::AttributeMap& attrs, 
-    imperative::NameVarBaseMap outs, const std::map<std::string, size_t>& out_nums)
-  {
-    auto tracer = imperative::GetCurrentTracer();
-    if (outs.size() == 0) {
-      if (out_nums.size() == 0) {
-        imperative::NameVarBaseMap outs_ = %s;
-        outs = std::move(outs_);
-      } else {
-        for (auto &pair : out_nums) {
-          for (size_t i = 0; i < pair.second; i ++) {
-            auto var_base_name = tracer->GenerateUniqueName();
-            auto out = new imperative::VarBase(var_base_name);
-            outs[pair.first].emplace_back(std::shared_ptr<imperative::VarBase>(out));
-          }
+R"(
+inline imperative::NameVarBaseMap %s(const imperative::NameVarBaseMap& ins, const framework::AttributeMap& attrs, 
+  imperative::NameVarBaseMap outs, const std::map<std::string, size_t>& out_nums)
+{
+  auto tracer = imperative::GetCurrentTracer();
+  if (outs.size() == 0) {
+    if (out_nums.size() == 0) {
+      imperative::NameVarBaseMap outs_ = %s;
+      outs = std::move(outs_);
+    } else {
+      for (auto &pair : out_nums) {
+        for (size_t i = 0; i < pair.second; i ++) {
+          auto var_base_name = tracer->GenerateUniqueName();
+          outs[pair.first].emplace_back(new imperative::VarBase(var_base_name));
         }
       }
     }
-    
-    {
-      py::gil_scoped_release release;
-      tracer->TraceOp("%s", std::move(ins), std::move(outs), std::move(attrs));
-      return outs;
-    }
-  }, py::arg("ins"), py::arg("attrs")=framework::AttributeMap(), 
-  py::arg("outs")=imperative::NameVarBaseMap(), 
-  py::arg("out_nums")=std::map<std::string, size_t>())";
+  }
+  
+  tracer->TraceOp("%s", std::move(ins), std::move(outs), std::move(attrs));
+  return outs;
+})";
 
-const char* PYBIND_ITEM_TEMPLATE = R"(  %s.def("%s", %s);)";
+const char* PYBIND_ITEM_TEMPLATE =
+R"(
+  %s.def("%s", &%s, py::arg("ins"), py::arg("attrs")=framework::AttributeMap(), py::arg("outs")=imperative::NameVarBaseMap(), 
+    py::arg("out_nums")=std::map<std::string, size_t>(), py::call_guard<py::gil_scoped_release>());)";
 
-static std::vector<std::string> GenerateOpFunctions(
-    const std::string& module_name) {
+// clang-format on
+
+static std::tuple<std::vector<std::string>, std::vector<std::string>>
+GenerateOpFunctions(const std::string& module_name) {
   auto& op_info_map = paddle::framework::OpInfoMap::Instance().map();
 
-  std::vector<std::string> op_function_list;
+  std::vector<std::string> op_function_list, bind_function_list;
   for (auto& pair : op_info_map) {
     auto& op_info = pair.second;
     auto op_proto = op_info.proto_;
@@ -85,18 +86,21 @@ static std::vector<std::string> GenerateOpFunctions(
     }
     outs_initializer += "}";
 
+    std::string func_name = "imperative_" + op_type;
+
     // generate op funtcion body
-    auto op_function_str = paddle::string::Sprintf(OP_FUNCTION_TEMPLATE,
-                                                   outs_initializer, op_type);
+    auto op_function_str = paddle::string::Sprintf(
+        OP_FUNCTION_TEMPLATE, func_name, outs_initializer, op_type);
 
     // generate pybind item
-    auto pybind_op_function = paddle::string::Sprintf(
-        PYBIND_ITEM_TEMPLATE, module_name.c_str(), op_type, op_function_str);
-    pybind_op_function += "\n";
-    op_function_list.emplace_back(std::move(pybind_op_function));
+    auto bind_function_str = paddle::string::Sprintf(
+        PYBIND_ITEM_TEMPLATE, module_name, op_type, func_name);
+
+    op_function_list.emplace_back(std::move(op_function_str));
+    bind_function_list.emplace_back(std::move(bind_function_str));
   }
 
-  return op_function_list;
+  return std::make_tuple(op_function_list, bind_function_list);
 }
 
 int main(int argc, char* argv[]) {
@@ -115,19 +119,21 @@ int main(int argc, char* argv[]) {
     out << "#include  " + header + "\n";
   }
 
+  // all op functions
+  auto op_funcs = GenerateOpFunctions("m");
+
   out << "namespace py = pybind11;"
       << "\n";
   out << "namespace paddle {\n"
-      << "namespace pybind {\n"
-      << "\n"
-      << "inline void BindOpFunctions(pybind11::module *module) {\n"
-      << "  auto m = module->def_submodule(\"ops\");\n\n";
-
-  // all op functions
-  auto op_funcs = GenerateOpFunctions("m");
+      << "namespace pybind {\n";
+  out << paddle::string::join_strings(std::get<0>(op_funcs), '\n');
+  out << "\n\n";
 
-  out << paddle::string::join_strings(op_funcs, '\n');
+  out << "inline void BindOpFunctions(pybind11::module *module) {\n"
+      << "  auto m = module->def_submodule(\"ops\");\n\n";
 
+  out << paddle::string::join_strings(std::get<1>(op_funcs), '\n');
+  out << "\n";
   out << "}\n\n"
       << "} // namespace pybind\n"
       << "} // namespace paddle\n";