[CINN] fix CINN graph symbolization topo sort fixed

paddle/fluid/framework/paddle2cinn/cinn_graph_symbolization.cc

@@ -162,22 +162,58 @@ CinnGraphSymbolization::CreateCinnScope(const FeedInfoMap& feed_map) {
 }
 
 std::vector<Node*> CinnGraphSymbolization::TopologicalSort() const {
-  std::unordered_set<Node*> op_nodes;
+  std::unordered_set<Node*> node_set;
   std::for_each(
-      graph_.Nodes().begin(), graph_.Nodes().end(), [&op_nodes](Node* n) {
-        if (n->IsOp()) {
-          op_nodes.emplace(n);
+      graph_.Nodes().begin(), graph_.Nodes().end(), [&node_set](Node* n) {
+        if (n && n->IsOp()) {
+          node_set.emplace(n);
         }
       });
 
+  std::vector<Node*> op_nodes(node_set.begin(), node_set.end());
+  std::stable_sort(op_nodes.begin(), op_nodes.end(), [](Node* op1, Node* op2) {
+    auto out1 = op1->outputs;
+    auto out2 = op2->outputs;
+
+    if (out1.size() != out2.size()) {
+      return out1.size() < out2.size();
+    }
+
+    auto var_compare = [](Node* var1, Node* var2) {
+      if (!var1) {
+        // the null node one the front
+        return true;
+      } else if (!var2) {
+        return false;
+      }
+      // sorted by name
+      return var1->Name() < var2->Name();
+    };
+    std::stable_sort(out1.begin(), out1.end(), var_compare);
+    std::stable_sort(out2.begin(), out2.end(), var_compare);
+
+    for (int i = 0; i < out1.size(); ++i) {
+      if (!out1[i] && !out2[i]) {
+        continue;
+      } else if (!out1[i]) {
+        return true;
+      } else if (!out2[i]) {
+        return false;
+      } else if (out1[i]->Name() != out2[i]->Name()) {
+        return out1[i]->Name() < out2[i]->Name();
+      }
+    }
+    return true;
+  });
+
   std::unordered_map<Node*, std::unordered_map<Node*, size_t>> adj_list;
   std::unordered_map<Node*, size_t> in_degrees;
   for (auto* n : op_nodes) {
     // the op's input is var
     for (auto* in_var : n->inputs) {
       // the var's input is op
       for (auto* in_op : in_var->inputs) {
-        if (op_nodes.count(in_op)) {
+        if (node_set.count(in_op)) {
           ++adj_list[in_op][n];
           ++in_degrees[n];
         }