add inplace attr to bn

python/paddle/fluid/layers/nn.py

@@ -1483,6 +1483,7 @@ def batch_norm(input,
                param_attr=None,
                bias_attr=None,
                data_layout='NCHW',
+               in_place=False,
                name=None,
                moving_mean_name=None,
                moving_variance_name=None):
@@ -1538,7 +1539,7 @@ def batch_norm(input,
     saved_mean = helper.create_tmp_variable(dtype=dtype, stop_gradient=True)
     saved_variance = helper.create_tmp_variable(dtype=dtype, stop_gradient=True)
 
-    batch_norm_out = helper.create_tmp_variable(dtype)
+    batch_norm_out = input if in_place else helper.create_tmp_variable(dtype)
 
     helper.append_op(
         type="batch_norm",