fix dygraph higer node creation (#47231)

* fix dygraph higer node creation

* fix eager generator

* modify generator code

* fix eager generator

paddle/fluid/eager/auto_code_generator/generator/eager_gen.py

@@ -1780,6 +1780,7 @@ class DygraphNodeGenerator(DygraphFunctionGeneratorBase):
             self.to_next_grad_name_mapping[grad_ret_name] = next_ret_name
 
     def GenerateHigherOrderNodeCreationCode(self):
+        has_higher_order_node = False
         namespace = self.namespace
         grad_api_contents = self.grad_api_contents
         forward_apis_dict = self.forward_apis_dict
@@ -1807,14 +1808,33 @@ class DygraphNodeGenerator(DygraphFunctionGeneratorBase):
             next_grad_node_out_list = next_node_generator.grad_node_out_list
 
             self.RecordGrad2NextGradNameMapping(next_node_generator)
+
+        is_invoke_forward_api = IsInvokeForwardApi(
+            self.grad_api_contents, self.forward_apis_dict
+        )
         if next_node_generator is not None:
+            has_higher_order_node = True
             return (
+                has_higher_order_node,
+                is_invoke_forward_api,
                 next_grad_node_creation_str,
                 next_grad_node_out_list,
                 next_node_generator.backward_forward_inputs_map,
             )
-        else:
-            return next_grad_node_creation_str, next_grad_node_out_list, None
+        elif not is_invoke_forward_api:
+            next_grad_node_creation_str = f"""  if(trace_backward) {{
+    PADDLE_THROW(phi::errors::Unavailable(
+    \"The Op {self.backward_api_name} doesn't have any grad\"
+    \"op. If you don't intend calculating higher order\"
+    \"derivatives, please set `create_graph`to False.\"));
+  }}"""
+        return (
+            has_higher_order_node,
+            is_invoke_forward_api,
+            next_grad_node_creation_str,
+            next_grad_node_out_list,
+            None,
+        )
 
     def GenerateNodeDeclaration(self):
         forward_op_name = self.forward_api_name
@@ -1906,6 +1926,8 @@ class DygraphNodeGenerator(DygraphFunctionGeneratorBase):
 
     def GenerateNodeDefinition(
         self,
+        has_higher_order_node,
+        is_invoke_forward_api,
         next_grad_node_creation_str,
         next_grad_node_out_list,
         backward_forward_inputs_map_next,
@@ -1920,9 +1942,6 @@ class DygraphNodeGenerator(DygraphFunctionGeneratorBase):
         backward_inplace_map = self.backward_inplace_map
         indent = GetIndent(1)
 
-        is_invoke_forward_api = IsInvokeForwardApi(
-            self.grad_api_contents, self.forward_apis_dict
-        )
         # Construct grad_api function args
         # Order: TensorWrappers, GradTensors, Attributes
         grad_api_args_len = (
@@ -1968,7 +1987,7 @@ class DygraphNodeGenerator(DygraphFunctionGeneratorBase):
             is_optional = name in self.optional_inputs
             tensor_wrapper_recover_str = f"{indent}auto {transformed_tensor_name} = egr::EagerUtils::RecoverTensorWrapper(&this->{tensor_wrapper_name});"
             if backward_inplace_map and name in backward_inplace_map.keys():
-                if len(next_grad_node_creation_str) > 0:
+                if has_higher_order_node:
                     if (
                         transformed_tensor_name
                         in backward_forward_inputs_map_next
@@ -2039,7 +2058,7 @@ class DygraphNodeGenerator(DygraphFunctionGeneratorBase):
 
                 # Inplace in backward op
                 if backward_inplace_map and name in backward_inplace_map.keys():
-                    if len(next_grad_node_creation_str) > 0:
+                    if has_higher_order_node:
                         if (
                             transformed_tensor_name
                             in backward_forward_inputs_map_next
@@ -2144,7 +2163,7 @@ class DygraphNodeGenerator(DygraphFunctionGeneratorBase):
                     inplace_str = f""" if (api_output_{out_index} != nullptr && can_be_inplaced) {{
       egr::EagerUtils::HandleViewBetweenInputAndOutput({inplace_grad_input_str}, api_output_{out_index});
     }}"""
-                    if len(next_grad_node_creation_str) > 0:
+                    if has_higher_order_node:
                         inplace_for_grad_outs_str += f"""
   if (trace_backward) {{
     {optional_inplace_str}
@@ -2236,7 +2255,7 @@ class DygraphNodeGenerator(DygraphFunctionGeneratorBase):
 
             else:
                 assert IsVectorTensorType(rtype)
-                if len(next_grad_node_creation_str) > 0:
+                if has_higher_order_node > 0:
                     output_autograd_meta = f"""
     auto& {transformed_tensor_name} = returns[{pos}];
     std::vector<egr::AutogradMeta*> {output_autograd_meta_vec_name} = egr::EagerUtils::autograd_meta(&{transformed_tensor_name});
@@ -2327,6 +2346,8 @@ class DygraphNodeGenerator(DygraphFunctionGeneratorBase):
         #####################
         # Higher-order GradNode generation
         (
+            has_higher_order_node,
+            is_invoke_forward_api,
             next_grad_node_creation_str,
             next_grad_node_out_list,
             backward_forward_inputs_map,
@@ -2335,6 +2356,8 @@ class DygraphNodeGenerator(DygraphFunctionGeneratorBase):
         self.GenerateNodeDeclaration()
 
         self.GenerateNodeDefinition(
+            has_higher_order_node,
+            is_invoke_forward_api,
             next_grad_node_creation_str,
             next_grad_node_out_list,
             backward_forward_inputs_map,