Avoid uneccesary vector copies in imperative_utils.cc

apache · Apr 10, 2019 · 42aecda · 42aecda
1 parent fde4963
commit 42aecda
Showing 1 changed file with 11 additions and 11 deletions.
diff --git a/src/imperative/imperative_utils.cc b/src/imperative/imperative_utils.cc
@@ -25,41 +25,41 @@ namespace imperative {
 
 inline std::vector<NDArray*> NodeInputs(const nnvm::IndexedGraph& idx,
                                         const int node_idx,
-                                        const std::vector<NDArray*> arrays) {
+                                        const std::vector<NDArray*>& arrays) {
   const nnvm::IndexedGraph::Node& node = idx[node_idx];
   const size_t num_inputs = node.inputs.size();
   std::vector<NDArray*> ndinputs;
   ndinputs.reserve(num_inputs);
   for (const auto& j : node.inputs) {
-    size_t eid = idx.entry_id(j);
+    const size_t eid = idx.entry_id(j);
     ndinputs.emplace_back(arrays[eid]);
   }
   return ndinputs;
 }
 
 inline std::vector<NDArray*> NodeOutputs(const nnvm::IndexedGraph& idx,
                                          const int node_idx,
-                                         const std::vector<NDArray*> arrays) {
+                                         const std::vector<NDArray*>& arrays) {
   const nnvm::IndexedGraph::Node& node = idx[node_idx];
   const size_t num_outputs = node.source->num_outputs();
   std::vector<NDArray*> ndoutputs;
   ndoutputs.reserve(num_outputs);
   for (size_t j = 0; j < num_outputs; ++j) {
-    size_t eid = idx.entry_id(node_idx, j);
+    const size_t eid = idx.entry_id(node_idx, j);
     ndoutputs.emplace_back(arrays[eid]);
   }
   return ndoutputs;
 }
 
 inline std::vector<OpReqType> NodeReq(const nnvm::IndexedGraph& idx,
                                       const int node_idx,
-                                      const std::vector<OpReqType> array_reqs) {
+                                      const std::vector<OpReqType>& array_reqs) {
   const nnvm::IndexedGraph::Node& node = idx[node_idx];
   const size_t num_outputs = node.source->num_outputs();
   std::vector<OpReqType> req;
   req.reserve(num_outputs);
   for (size_t j = 0; j < num_outputs; ++j) {
-    size_t eid = idx.entry_id(node_idx, j);
+    const size_t eid = idx.entry_id(node_idx, j);
     req.push_back(array_reqs[eid]);
   }
   return req;
@@ -68,11 +68,11 @@ inline std::vector<OpReqType> NodeReq(const nnvm::IndexedGraph& idx,
 inline void InvokeOperator(const nnvm::IndexedGraph& idx,
                            const int node_idx,
                            const bool retain_graph,
-                           const std::vector<NDArray*> arrays,
+                           const std::vector<NDArray*>& arrays,
                            Context ctx,
                            std::vector<OpStatePtr>* p_states,
-                           std::vector<NDArray*> ndinputs,
-                           std::vector<NDArray*> ndoutputs,
+                           std::vector<NDArray*>& ndinputs,
+                           std::vector<NDArray*>& ndoutputs,
                            std::vector<OpReqType> *p_req,
                            std::vector<uint32_t> *p_ref_count,
                            std::function<void(const OpStatePtr &state)> invoke) {
@@ -125,7 +125,7 @@ inline void InvokeOperator(const nnvm::IndexedGraph& idx,
 void RunGraph(
     const bool retain_graph,
     const nnvm::IndexedGraph& idx,
-    const std::vector<NDArray*> arrays,
+    const std::vector<NDArray*>& arrays,
     size_t node_start, size_t node_end,
     std::vector<OpReqType>&& array_reqs,
     std::vector<uint32_t>&& ref_count,
@@ -161,7 +161,7 @@ void NaiveRunGraph(
     const bool retain_graph,
     const Context& default_ctx,
     const nnvm::IndexedGraph& idx,
-    const std::vector<NDArray*> arrays,
+    const std::vector<NDArray*>& arrays,
     size_t node_start, size_t node_end,
     std::vector<OpReqType>&& array_reqs,
     std::vector<uint32_t>&& ref_count,