Fix warning info of build_strategy (#19805)

* fix warning info
test=develop

* fix bug of all_reduce_deps_pass
test=develop

paddle/fluid/framework/details/build_strategy.cc

@@ -110,7 +110,8 @@ class ParallelExecutorPassBuilder : public ir::PassBuilder {
              "mode.";
       strategy_.fuse_all_optimizer_ops_ = false;
       LOG_IF(WARNING, strategy_.fuse_all_reduce_ops_ == true)
-          << "fuse_all_optimizer_ops only work in Reducer mode.";
+          << "fuse_all_optimizer_ops only works under AllReduce "
+             "mode.";
       strategy_.fuse_all_reduce_ops_ = false;
     }
     if (strategy_.reduce_ == BuildStrategy::ReduceStrategy::kAllReduce) {
@@ -132,7 +133,8 @@ class ParallelExecutorPassBuilder : public ir::PassBuilder {
     }
     if (strategy_.fuse_all_reduce_ops_ == true) {
       LOG_IF(WARNING, strategy_.async_mode_)
-          << "fuse_all_optimizer_ops only work in Reducer mode.";
+          << "Currently, fuse_all_reduce_ops doesn't work under "
+             "async mode.";
       strategy_.fuse_all_reduce_ops_ = !strategy_.async_mode_;
     }
   }

paddle/fluid/framework/ir/multi_devices_graph_pass/all_reduce_deps_pass.cc

@@ -131,7 +131,7 @@ class AllReduceDepsPass : public ir::Pass {
            auto right_in_vars =
                details::DynamicCast<details::VarHandle>(right->Inputs());
            PADDLE_ENFORCE_GT(left_in_vars.size(), 0);
-           PADDLE_ENFORCE_EQ(left_in_vars.size(), right_in_vars.size());
+           PADDLE_ENFORCE_GT(right_in_vars.size(), 0);
            return left_in_vars[0]->Name() > right_in_vars[0]->Name();
          });