[XPU] bkcl_broadcast support int64_t (#53720)

paddle/fluid/distributed/collective/process_group_bkcl.cc

@@ -334,6 +334,19 @@ std::shared_ptr<ProcessGroup::Task> ProcessGroupBKCL::Broadcast(
                 << ", root: " << root << ", numel: " << input.numel()
                 << ", dtype: " << input.type() << ", sync_op: " << sync_op
                 << ", use_calc_stream: " << use_calc_stream;
+        if (framework::TransToProtoVarType(input.dtype()) ==
+            framework::proto::VarType::INT64) {
+          // special for int64_t, send as int32_t with DOUBLE NUMEL
+          int r = bkcl_broadcast(
+              comm,
+              input.data(),
+              output->data(),
+              input.numel() * 2,
+              platform::ToBKCLDataType(framework::proto::VarType::INT32),
+              root,
+              stream);
+          return r;
+        } else {
           int r =
               bkcl_broadcast(comm,
                              input.data(),
@@ -344,6 +357,7 @@ std::shared_ptr<ProcessGroup::Task> ProcessGroupBKCL::Broadcast(
                              root,
                              stream);
           return r;
+        }
       },
       CommType::BROADCAST,
       sync_op,