fix graph attr copy issues, test=develop (#23191)

paddle/fluid/framework/details/multi_devices_helper.cc

@@ -171,6 +171,10 @@ std::vector<std::unique_ptr<ir::Graph>> TrySeparateToMultipleSingleDeviceGraphs(
           "issue at https://github.com/PaddlePaddle/Paddle/issues/new. And "
           "we will resolve it with high priority."));
 
+  if (place_num == 1) {
+    return {};
+  }
+
   std::vector<std::unique_ptr<ir::Graph>> graphs(place_num);
   for (auto &g : graphs) {
     g.reset(new ir::Graph(ProgramDesc()));
@@ -208,6 +212,10 @@ std::vector<std::unique_ptr<ir::Graph>> TrySeparateToMultipleSingleDeviceGraphs(
   graph->Erase(kGraphVars);
   graph->Erase(kGraphDepVars);
 
+  for (auto &g : graphs) {
+    CopyGraphAttrIfExists<ProgramDescs>(*graph, g.get(), kProgramDescs);
+    CopyGraphAttrIfExists<FusedVars>(*graph, g.get(), kFusedVars);
+  }
   return graphs;
 }
 

paddle/fluid/framework/details/multi_devices_helper.h

@@ -108,6 +108,15 @@ bool HasDropLastReadOp(const ir::Graph &graph);
 
 bool HasKeepLastReadOp(const ir::Graph &graph);
 
+template <typename T>
+void CopyGraphAttrIfExists(const ir::Graph &src, ir::Graph *dst,
+                           const std::string &name) {
+  if (src.Has(name)) {
+    auto &attr = src.Get<T>(name);
+    dst->Set(name, new T(attr));
+  }
+}
+
 }  // namespace details
 }  // namespace framework
 }  // namespace paddle

paddle/fluid/framework/ir/graph_test.cc

@@ -14,6 +14,7 @@ limitations under the License. */
 
 #include "paddle/fluid/framework/ir/graph.h"
 #include "gtest/gtest.h"
+#include "paddle/fluid/framework/details/multi_devices_helper.h"
 #include "paddle/fluid/framework/op_registry.h"
 #include "paddle/fluid/framework/operator.h"
 #include "paddle/fluid/framework/program_desc.h"
@@ -252,5 +253,22 @@ TEST(GraphTest, TestException) {
   }
   ASSERT_TRUE(not_met_exception);
 }
+
+TEST(GraphTest, TestAttrCopy) {
+  ProgramDesc prog;
+  ir::Graph src_g(prog);
+  ir::Graph dst_g(prog);
+  const std::string kIntValue = "int_value";
+  const std::string kFloatValue = "float_value";
+  const int INT_VALUE = 3;
+  src_g.Set<int>(kIntValue, new int(INT_VALUE));
+  details::CopyGraphAttrIfExists<int>(src_g, &dst_g, kIntValue);
+  details::CopyGraphAttrIfExists<float>(src_g, &dst_g, kFloatValue);
+
+  ASSERT_TRUE(dst_g.Has(kIntValue));
+  ASSERT_EQ(dst_g.Get<int>(kIntValue), INT_VALUE);
+  ASSERT_FALSE(dst_g.Has(kFloatValue));
+}
+
 }  // namespace framework
 }  // namespace paddle