Add bias for gru_unit_op and fix activation function (#10087)

python/paddle/fluid/layers/nn.py

@@ -699,8 +699,8 @@ def dynamic_gru(input,
 def gru_unit(input,
              hidden,
              size,
-             weight=None,
-             bias=None,
+             param_attr=None,
+             bias_attr=None,
              activation='tanh',
              gate_activation='sigmoid'):
     """
@@ -731,8 +731,8 @@ def gru_unit(input,
         input (Variable): The fc transformed input value of current step.
         hidden (Variable): The hidden value of lstm unit from previous step.
         size (integer): The input dimension value.
-        weight (ParamAttr): The weight parameters for gru unit. Default: None
-        bias (ParamAttr): The bias parameters for gru unit. Default: None
+        param_attr (ParamAttr): The weight parameters for gru unit. Default: None
+        bias_attr (ParamAttr): The bias parameters for gru unit. Default: None
         activation (string): The activation type for cell (actNode).
                              Default: 'tanh'
         gate_activation (string): The activation type for gates (actGate).
@@ -764,34 +764,31 @@ def gru_unit(input,
     size = size / 3
 
     # create weight
-    if weight is None:
-        weight = helper.create_parameter(
-            attr=helper.param_attr, shape=[size, 3 * size], dtype=dtype)
+    weight = helper.create_parameter(
+        attr=helper.param_attr, shape=[size, 3 * size], dtype=dtype)
 
+    gate = helper.create_tmp_variable(dtype)
+    reset_hidden_pre = helper.create_tmp_variable(dtype)
+    updated_hidden = helper.create_tmp_variable(dtype)
+    inputs = {'Input': input, 'HiddenPrev': hidden, 'Weight': weight}
     # create bias
-
-    if bias is None:
+    if helper.bias_attr:
         bias_size = [1, 3 * size]
         bias = helper.create_parameter(
             attr=helper.bias_attr, shape=bias_size, dtype=dtype, is_bias=True)
-
-    gate = helper.create_tmp_variable(dtype)
-    reset_hidden_pre = helper.create_tmp_variable(dtype)
-    updated_hidden = helper.create_tmp_variable(dtype)
+        inputs['Bias'] = bias
 
     helper.append_op(
         type='gru_unit',
-        inputs={'Input': input,
-                'HiddenPrev': hidden,
-                'Weight': weight},
+        inputs=inputs,
         outputs={
             'Gate': gate,
             'ResetHiddenPrev': reset_hidden_pre,
             'Hidden': updated_hidden,
         },
         attrs={
-            'activation': 0,
-            'gate_activation': 1,
+            'activation': 2,  # tanh
+            'gate_activation': 1,  # sigmoid
         })
 
     return updated_hidden, reset_hidden_pre, gate