clean tensor array (#19930)

test=develop

paddle/fluid/framework/details/scope_buffered_ssa_graph_executor.cc

@@ -74,7 +74,8 @@ FeedFetchList ScopeBufferedSSAGraphExecutor::Run(
   }
 
   ++drop_scope_counter_;
-  if (drop_scope_counter_ == strategy_.num_iteration_per_drop_scope_) {
+  if (drop_scope_counter_ == strategy_.num_iteration_per_drop_scope_ ||
+      DropScopeOrNot()) {
     DropLocalExeScopes();
   }
 
@@ -93,6 +94,19 @@ FeedFetchList ScopeBufferedSSAGraphExecutor::Run(
   }
 }
 
+bool ScopeBufferedSSAGraphExecutor::DropScopeOrNot() const {
+  for (auto &var : tensor_array_vars_) {
+    auto tensor_array = var->GetMutable<LoDTensorArray>();
+    for (LoDTensor &tensor : *tensor_array) {
+      if (tensor.IsInitialized()) {
+        return true;
+      }
+    }
+    tensor_array->clear();
+  }
+  return false;
+}
+
 void ScopeBufferedSSAGraphExecutor::InitVariables() {
   for (auto &info : tmp_var_infos_) {
     for (auto &pair : info) {
@@ -165,6 +179,9 @@ void ScopeBufferedSSAGraphExecutor::PrepareLocalExeScopes() {
         Variable *tmp_var = local_scope->Var(info.name_);
         preserve_vars_[idx].emplace(tmp_var);
         tmp_var_infos_[idx].emplace_back(tmp_var, info.type_);
+        if (info.type_ == proto::VarType::LOD_TENSOR_ARRAY) {
+          tensor_array_vars_.emplace_back(tmp_var);
+        }
       }
     }
   }

paddle/fluid/framework/details/scope_buffered_ssa_graph_executor.h

@@ -61,6 +61,8 @@ class ScopeBufferedSSAGraphExecutor : public SSAGraphExecutor {
  private:
   void InitVariables();
 
+  bool DropScopeOrNot() const;
+
   size_t drop_scope_counter_{0};
   ExecutionStrategy strategy_;
   std::unique_ptr<SSAGraphExecutor> underlying_executor_;
@@ -71,8 +73,11 @@ class ScopeBufferedSSAGraphExecutor : public SSAGraphExecutor {
   std::vector<std::vector<std::pair<Variable*, proto::VarType::Type>>>
       tmp_var_infos_;
 
+  std::vector<Variable*> tensor_array_vars_;
+
   std::vector<VariableInfo> var_infos_;
   std::vector<platform::Place> places_;
+
   ScopeBufferedMonitor scope_monitor_;
 };
 }  // namespace details