!8152 Resolve GPT net stack overflow problem, due to infer process.

Merge pull request !8152 from 张清华/grad_opt2

mindspore/ccsrc/pipeline/jit/static_analysis/evaluator.cc

@@ -65,33 +65,57 @@ AnalysisContextPtr BaseFuncGraphEvaluator::MakeContext(const AnalysisEnginePtr &
   return context;
 }
 
-static std::vector<AnfNodePtr> FastShadowSort(const AnfNodePtr &ret_node) {
-  auto current_func_graph = ret_node->func_graph();
+// Return CNodes set that may contain duplicates from a DAG function graph.
+// Should check the results' second item as ignored flag before use them, to avoid processing repeatedly.
+static inline std::vector<std::pair<AnfNodePtr, bool>> SortCNodesContainDup(const AnfNodePtr &root_node) {
+  auto current_func_graph = root_node->func_graph();
   MS_EXCEPTION_IF_NULL(current_func_graph);
 
-  std::vector<AnfNodePtr> sorted_nodes;
-  auto seen = NewSeenGeneration();
+  std::vector<std::pair<AnfNodePtr, bool>> sorted_nodes;  // Record {node, ignored_flag}.
+  std::unordered_map<AnfNodePtr, size_t> checked_cnodes;  // Record {node, position_in_sorted_nodes}
   std::size_t index = 0;
-  sorted_nodes.emplace_back(ret_node);
+  sorted_nodes.emplace_back(std::pair(root_node, false));
   while (index < sorted_nodes.size()) {
-    auto current = sorted_nodes[index];
-    index++;
+    auto current = sorted_nodes[index].first;
     MS_EXCEPTION_IF_NULL(current);
-    if (current->isa<CNode>()) {
+    auto ignored_flag = sorted_nodes[index].second;
+    if (!ignored_flag && current->isa<CNode>()) {
       auto &inputs = current->cast<CNodePtr>()->inputs();
-      for (auto it = inputs.begin(); it != inputs.end(); it++) {
+      for (auto it = inputs.crbegin(); it != inputs.crend(); it++) {
         AnfNodePtr input = *it;
-        if (input != nullptr && input->isa<CNode>() && input->seen_ != seen &&
-            input->func_graph() == current_func_graph) {
-          sorted_nodes.emplace_back(input);
-          input->seen_ = seen;
+        if (input == nullptr || !input->isa<CNode>() || input->func_graph() != current_func_graph) {
+          continue;
+        }
+        auto checked_item = checked_cnodes.find(input);
+        if (checked_item == checked_cnodes.end()) {  // Not met before.
+          checked_cnodes.insert({input, sorted_nodes.size()});
+          sorted_nodes.emplace_back(std::pair(input, false));
+        } else {  // Checked, should update flag and new position.
+          auto pos = checked_item->second;
+          sorted_nodes[pos].second = true;                     // Set ignore flag.
+          checked_cnodes[input] = sorted_nodes.size();         // Update a new position.
+          sorted_nodes.emplace_back(std::pair(input, false));  // Insert duplicate node into new position.
         }
       }
     }
+    index++;
   }
   return sorted_nodes;
 }
 
+// Return CNodes set that root at the bottom.
+static inline std::vector<AnfNodePtr> SortReverseCNodes(const AnfNodePtr &root_node) {
+  std::vector<AnfNodePtr> res;
+  auto nodes_with_flag = SortCNodesContainDup(root_node);
+  for (auto it = nodes_with_flag.crbegin(); it != nodes_with_flag.crend(); it++) {
+    if (it->second) {  // Check ignored flag.
+      continue;
+    }
+    res.emplace_back(it->first);
+  }
+  return res;
+}
+
 EvalResultPtr BaseFuncGraphEvaluator::Eval(AnalysisEnginePtr engine, const AbstractBasePtrList &args_spec_list) {
   FuncGraphPtr fg = GetFuncGraph(engine, args_spec_list);
   MS_EXCEPTION_IF_NULL(fg);
@@ -123,9 +147,12 @@ EvalResultPtr BaseFuncGraphEvaluator::Eval(AnalysisEnginePtr engine, const Abstr
                       << MsContext::GetInstance()->get_param<uint32_t>(MS_CTX_MAX_CALL_DEPTH)
                       << ", please call 'context.set_context(max_call_depth=value)' to adjust this value.";
   }
-  std::vector<AnfNodePtr> nodes = FastShadowSort(func_node);
-  for (auto it = nodes.crbegin(); it != nodes.crend(); it++) {
-    const auto &node = *it;
+  auto nodes_with_flag = SortCNodesContainDup(func_node);
+  for (auto it = nodes_with_flag.crbegin(); it != nodes_with_flag.crend(); it++) {
+    if (it->second) {  // Check ignored flag.
+      continue;
+    }
+    const auto &node = it->first;
     AnfNodeConfigPtr node_conf = engine->MakeConfig(node, graph_context_);
     MS_LOG(DEBUG) << "Analysis node begin, func graph: " << fg.get() << fg->ToString()
                   << ", node_conf: " << node_conf->ToString();