diff --git a/paddle/fluid/framework/ir/fusion_group/code_generator.cc b/paddle/fluid/framework/ir/fusion_group/code_generator.cc
index 24c3f876b94f49cd5543a463682304a07973ad6f..fd224de483b2e066fe13851eb03eba54f4b21a89 100644
--- a/paddle/fluid/framework/ir/fusion_group/code_generator.cc
+++ b/paddle/fluid/framework/ir/fusion_group/code_generator.cc
@@ -77,6 +77,7 @@ std::vector<OperationExpression> CodeGenerator::ConvertToExpressions(
       auto* op = node->Op();
       AttributeMap attr = *(op->MutableAttrMap());
 
+      // Input ids should be set in fixed order, like:
       //  - X, Y in forward operations
       //  - X, Y, Out, out@GRAD in backward operations
       std::vector<int> input_ids;
diff --git a/paddle/fluid/framework/ir/fusion_group/code_generator_helper.cc b/paddle/fluid/framework/ir/fusion_group/code_generator_helper.cc
index 1b8c6b2fdfe23fe628f1f575db759011c5a3b20d..62e226d891f8ea60fc9e1242c3cf1ae904a13101 100644
--- a/paddle/fluid/framework/ir/fusion_group/code_generator_helper.cc
+++ b/paddle/fluid/framework/ir/fusion_group/code_generator_helper.cc
@@ -20,11 +20,6 @@ limitations under the License. */
 #include "glog/logging.h"
 #include "paddle/fluid/framework/block_desc.h"
 #include "paddle/fluid/framework/ir/fusion_group/operation.h"
-#include "paddle/fluid/framework/op_call_stack.h"
-#include "paddle/fluid/framework/op_proto_maker.h"
-#include "paddle/fluid/framework/operator.h"
-#include "paddle/fluid/framework/program_desc.h"
-#include "paddle/fluid/framework/shape_inference.h"
 #include "paddle/fluid/framework/var_type_inference.h"
 
 namespace paddle {
@@ -164,8 +159,7 @@ std::string OperationExpression::GetRHS(std::unordered_set<int>* used,
                               ">. Received %d.",
                               index, op_type_, input_ids_[index]));
         // TODO(wangchaochaohu): Here fp16 convert to float to do comupte, we
-        // need
-        // to add general fp16 compute later.
+        // need to add general fp16 compute later.
         std::string var_name;
         if (rhs_type_ == "float16") {
           half2fp32_statement->append(OptimzeFP16RHS(used, index, input_ids_));
diff --git a/paddle/fluid/framework/ir/fusion_group/operation.cc b/paddle/fluid/framework/ir/fusion_group/operation.cc
index 99ae8be37b97e2f7782b8b4123dc1fdf557038b6..6c4bb98e1b62cb013a1ef4f4f91751ce2065910d 100644
--- a/paddle/fluid/framework/ir/fusion_group/operation.cc
+++ b/paddle/fluid/framework/ir/fusion_group/operation.cc
@@ -199,7 +199,7 @@ void OperationMap::InsertMultivariateElementwiseOperations() {
   auto insert_handler_without_input = [&](std::string op_type, std::string expr,
                                           std::vector<std::string> grad_exprs) {
     int type = 0;
-    int num_oprands = -1;
+    int num_oprands = 0;
     Insert(type, num_oprands, op_type, expr, grad_exprs, {}, {"Out"});
   };
   // fill_constant: