fix the bug of assert_is_op_output. test=develop (#22262)

paddle/fluid/framework/ir/graph_pattern_detector.cc

@@ -656,6 +656,17 @@ bool HasInput(Node *op, const std::string &argument) {
   return true;
 }
 
+bool HasOutput(Node *op, const std::string &argument) {
+  PADDLE_ENFORCE_EQ(
+      op->IsOp(), true,
+      platform::errors::InvalidArgument(
+          "First parameter of function HasOuput must be Node::Op"));
+  auto const &names = op->Op()->OutputNames();
+  if (std::find(names.begin(), names.end(), argument) == names.end())
+    return false;
+  return true;
+}
+
 bool IsNthOutput(Node *var, Node *op, const std::string &argument, size_t nth) {
   PADDLE_ENFORCE_EQ(
       var->IsVar(), true,
@@ -665,7 +676,8 @@ bool IsNthOutput(Node *var, Node *op, const std::string &argument, size_t nth) {
       op->IsOp(), true,
       platform::errors::InvalidArgument(
           "Second parameter of function IsNthOutput must be Node::Op"));
-  if (op->Op()->Output(argument).size() <= nth) return false;
+  if (!HasOutput(op, argument) || op->Op()->Output(argument).size() <= nth)
+    return false;
   return var->Name() == op->Op()->Output(argument)[nth];
 }
 

paddle/fluid/framework/ir/graph_pattern_detector.h

@@ -318,6 +318,9 @@ bool IsNthInput(Node* var, Node* op, const std::string& argument, size_t nth);
 // Check whether the op node has input of given name.
 bool HasInput(Node* op, const std::string& argument);
 
+// Check whether the op node has output of given name.
+bool HasOutput(Node* op, const std::string& argument);
+
 // Tell whether a var node is a op node's nth output.
 bool IsNthOutput(Node* var, Node* op, const std::string& argument, size_t nth);