Remove the clone of program in C++ Executor.Run().

paddle/fluid/framework/executor.cc

@@ -106,10 +106,11 @@ void Executor::Run(const ProgramDesc& pdesc, Scope* scope, int block_id,
 // and feed_holder_name. Raise exception when any mismatch is found.
 // Return true if the block has feed operators and holder of matching info.
 static bool has_feed_operators(
-    BlockDesc* block, std::map<std::string, const LoDTensor*>& feed_targets,
+    const BlockDesc& block,
+    std::map<std::string, const LoDTensor*>& feed_targets,
     const std::string& feed_holder_name) {
   size_t feed_count = 0;
-  for (auto* op : block->AllOps()) {
+  for (auto* op : block.AllOps()) {
     if (op->Type() == kFeedOpType) {
       feed_count++;
       PADDLE_ENFORCE_EQ(op->Input("X")[0], feed_holder_name,
@@ -128,7 +129,7 @@ static bool has_feed_operators(
         "The number of feed operators should match 'feed_targets'");
 
     // When feed operator are present, so should be feed_holder
-    auto var = block->FindVar(feed_holder_name);
+    auto var = block.FindVar(feed_holder_name);
     PADDLE_ENFORCE_NOT_NULL(var, "Block should already have a '%s' variable",
                             feed_holder_name);
     PADDLE_ENFORCE_EQ(var->GetType(), proto::VarType::FEED_MINIBATCH,
@@ -146,10 +147,10 @@ static bool has_feed_operators(
 // and fetch_holder_name. Raise exception when any mismatch is found.
 // Return true if the block has fetch operators and holder of matching info.
 static bool has_fetch_operators(
-    BlockDesc* block, std::map<std::string, LoDTensor*>& fetch_targets,
+    const BlockDesc& block, std::map<std::string, LoDTensor*>& fetch_targets,
     const std::string& fetch_holder_name) {
   size_t fetch_count = 0;
-  for (auto* op : block->AllOps()) {
+  for (auto* op : block.AllOps()) {
     if (op->Type() == kFetchOpType) {
       fetch_count++;
       PADDLE_ENFORCE_EQ(op->Output("Out")[0], fetch_holder_name,
@@ -168,7 +169,7 @@ static bool has_fetch_operators(
         "The number of fetch operators should match 'fetch_targets'");
 
     // When fetch operator are present, so should be fetch_holder
-    auto var = block->FindVar(fetch_holder_name);
+    auto var = block.FindVar(fetch_holder_name);
     PADDLE_ENFORCE_NOT_NULL(var, "Block should already have a '%s' variable",
                             fetch_holder_name);
     PADDLE_ENFORCE_EQ(var->GetType(), proto::VarType::FETCH_LIST,
@@ -184,10 +185,19 @@ void Executor::Run(const ProgramDesc& program, Scope* scope,
                    std::map<std::string, LoDTensor*>& fetch_targets,
                    const std::string& feed_holder_name,
                    const std::string& fetch_holder_name) {
-  auto* copy_program = new ProgramDesc(program);
+  bool has_feed_ops =
+      has_feed_operators(program.Block(0), feed_targets, feed_holder_name);
+  bool has_fetch_ops =
+      has_fetch_operators(program.Block(0), fetch_targets, fetch_holder_name);
+
+  ProgramDesc* copy_program = const_cast<ProgramDesc*>(&program);
+  if (!has_feed_ops || !has_fetch_ops) {
+    copy_program = std::unique_ptr<ProgramDesc>(new ProgramDesc(program)).get();
+  }
+
   auto* global_block = copy_program->MutableBlock(0);
 
-  if (!has_feed_operators(global_block, feed_targets, feed_holder_name)) {
+  if (!has_feed_ops) {
     // create feed_holder variable
     auto* feed_holder = global_block->Var(feed_holder_name);
     feed_holder->SetType(proto::VarType::FEED_MINIBATCH);
@@ -220,7 +230,7 @@ void Executor::Run(const ProgramDesc& program, Scope* scope,
     }
   }
 
-  if (!has_fetch_operators(global_block, fetch_targets, fetch_holder_name)) {
+  if (!has_fetch_ops) {
     // create fetch_holder variable
     auto* fetch_holder = global_block->Var(fetch_holder_name);
     fetch_holder->SetType(proto::VarType::FETCH_LIST);
@@ -254,8 +264,6 @@ void Executor::Run(const ProgramDesc& program, Scope* scope,
           GetFetchVariable(*scope, fetch_holder_name, idx);
     }
   }
-
-  delete copy_program;
 }
 
 ExecutorPrepareContext* Executor::Prepare(const ProgramDesc& program,
@@ -305,9 +313,8 @@ void Executor::RunPreparedContext(ExecutorPrepareContext* ctx, Scope* scope,
   }    // if (create_vars)
 
   for (auto& op : ctx->ops_) {
-    VLOG(4) << place_ << " " << op->DebugStringEx(local_scope);
-    op->Run(*local_scope, place_);
     VLOG(3) << place_ << " " << op->DebugStringEx(local_scope);
+    op->Run(*local_scope, place_);
 
     if (FLAGS_benchmark) {
       VLOG(2) << "Memory used after operator " + op->Type() + " running: "