[XPU] bkcl_broadcast support int64_t (#53720)

paddle/fluid/distributed/collective/process_group_bkcl.cc

@@ -334,16 +334,30 @@ 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;
-        int r =
-            bkcl_broadcast(comm,
-                           input.data(),
-                           output->data(),
-                           input.numel(),
-                           platform::ToBKCLDataType(
-                               framework::TransToProtoVarType(input.type())),
-                           root,
-                           stream);
-        return r;
+        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(),
+                             output->data(),
+                             input.numel(),
+                             platform::ToBKCLDataType(
+                                 framework::TransToProtoVarType(input.type())),
+                             root,
+                             stream);
+          return r;
+        }
       },
       CommType::BROADCAST,
       sync_op,