solve auto_aprallel pp2 with fp16 question (#49913)

python/paddle/distributed/auto_parallel/completion.py

@@ -1850,7 +1850,7 @@ class Completer:
                             op_dist_attr.set_output_dims_mapping(
                                 input_var.name, ref_dims_mapping
                             )
-
+                        if "SkipUpdate" not in input_name:
                             input_var_attr.process_mesh = ref_process_mesh
                             self._dist_context.set_tensor_dist_attr_for_program(
                                 input_var, input_var_attr