fix default value. test=develop

paddle/fluid/framework/details/memory_optimize_helper.cc

@@ -461,11 +461,21 @@ void ControlFlowGraph::LiveVariableAnalysis() {
       }
     }
   }
+
+  for (auto* op : ops_) {
+    unlived_vars_[op] = std::set<std::string>();
+    for (auto& var : this->LiveIn(op)) {
+      if (!this->LiveOut(op).count(var)) {
+        unlived_vars_[op].insert(var);
+      }
+    }
+  }
 }
 
 void ControlFlowGraph::RenameVarInCFGGraph(const std::string& old_node,
                                            const std::string& new_node,
                                            int begin_idx) {
+  std::vector<bool> need_update(ops_.size(), false);
   // update graph from begin idx to the end
   for (size_t i = begin_idx; i != ops_.size(); ++i) {
     auto* op = ops_[i];
@@ -480,15 +490,27 @@ void ControlFlowGraph::RenameVarInCFGGraph(const std::string& old_node,
     if (live_in_[op].find(old_node) != live_in_[op].end()) {
       live_in_[op].erase(old_node);
       live_in_[op].insert(new_node);
+      need_update[i] = true;
     }
     if (live_out_[op].find(old_node) != live_out_[op].end()) {
       live_out_[op].erase(old_node);
       live_out_[op].insert(new_node);
+      need_update[i] = true;
+    }
+  }
+
+  for (size_t i = begin_idx; i < ops_.size(); ++i) {
+    if (!need_update[i]) continue;
+    auto* op = ops_[i];
+    for (auto& var : this->LiveIn(op)) {
+      if (!this->LiveOut(op).count(var)) {
+        unlived_vars_[op].insert(var);
+      }
     }
   }
 }
 
-const std::set<std::string> ControlFlowGraph::LiveIn(ir::Node* op) const {
+const std::set<std::string>& ControlFlowGraph::LiveIn(ir::Node* op) const {
   auto it = live_in_.find(op);
   PADDLE_ENFORCE(
       it != live_in_.end(),
@@ -496,7 +518,7 @@ const std::set<std::string> ControlFlowGraph::LiveIn(ir::Node* op) const {
   return it->second;
 }
 
-const std::set<std::string> ControlFlowGraph::LiveOut(ir::Node* op) const {
+const std::set<std::string>& ControlFlowGraph::LiveOut(ir::Node* op) const {
   auto it = live_out_.find(op);
   PADDLE_ENFORCE(
       it != live_out_.end(),
@@ -504,15 +526,24 @@ const std::set<std::string> ControlFlowGraph::LiveOut(ir::Node* op) const {
   return it->second;
 }
 
-const std::set<std::string> ControlFlowGraph::Use(ir::Node* op) const {
+const std::set<std::string>& ControlFlowGraph::Use(ir::Node* op) const {
   auto it = uses_.find(op);
   PADDLE_ENFORCE(
       it != uses_.end(),
-      string::Sprintf("Expect %s in live_out, but Not Found.", op->Name()));
+      string::Sprintf("Expect %s in use, but Not Found.", op->Name()));
+  return it->second;
+}
+
+const std::set<std::string>& ControlFlowGraph::Unlived(ir::Node* op) const {
+  auto it = unlived_vars_.find(op);
+  PADDLE_ENFORCE(
+      it != unlived_vars_.end(),
+      string::Sprintf("Expect %s in unlived_set, but Not Found.", op->Name()));
+  return it->second;
   return it->second;
 }
 
-const std::vector<ir::Node*> ControlFlowGraph::Ops() const { return ops_; }
+const std::vector<ir::Node*>& ControlFlowGraph::Ops() const { return ops_; }
 
 std::vector<ir::Node*>& ControlFlowGraph::Ops() { return ops_; }
 

paddle/fluid/framework/details/memory_optimize_helper.h

@@ -92,10 +92,11 @@ class ControlFlowGraph {
   void RenameVarInCFGGraph(const std::string& old_node,
                            const std::string& new_node, int begin_idx);
 
-  const std::set<std::string> LiveIn(ir::Node* op) const;
-  const std::set<std::string> LiveOut(ir::Node* op) const;
-  const std::set<std::string> Use(ir::Node* op) const;
-  const std::vector<ir::Node*> Ops() const;
+  const std::set<std::string>& LiveIn(ir::Node* op) const;
+  const std::set<std::string>& LiveOut(ir::Node* op) const;
+  const std::set<std::string>& Use(ir::Node* op) const;
+  const std::set<std::string>& Unlived(ir::Node* op) const;
+  const std::vector<ir::Node*>& Ops() const;
   std::vector<ir::Node*>& Ops();
 
   // for ssa-graph nodes
@@ -117,6 +118,7 @@ class ControlFlowGraph {
   VarSetMap live_out_;
   VarSetMap uses_;  // op inputs
   VarSetMap defs_;  // op outputs
+  std::unordered_map<ir::Node*, std::set<std::string>> unlived_vars_;
 
   std::vector<ir::Node*> ops_;  // op sequence by topology sort
 };

paddle/fluid/framework/details/memory_optimize_pass.cc

@@ -118,13 +118,11 @@ std::unique_ptr<ir::Graph> MemoryOptimizePass::ApplyImpl(
       }
     }
     // fill the pool
-    for (auto var : cfg_->LiveIn(op)) {
-      if (cfg_->LiveOut(op).count(var) == 0) {
-        ir::Node* var_node = cfg_->GetNodeByName(var, op);
-        if (var_node == nullptr || var_node->IsCtrlVar()) continue;
-        if (NodeCanReused(var_node) && !pool_.Has(var_node)) {
-          pool_.Insert(var_node);
-        }
+    for (auto& var : cfg_->Unlived(op)) {
+      ir::Node* var_node = cfg_->GetNodeByName(var, op);
+      if (var_node == nullptr || var_node->IsCtrlVar()) continue;
+      if (NodeCanReused(var_node) && !pool_.Has(var_node)) {
+        pool_.Insert(var_node);
       }
     }
   }