!2810 Add operator adapting in ME for Softsign

Merge pull request !2810 from zhangzheng/softsign

mindspore/ops/_grad/grad_nn_ops.py

@@ -336,6 +336,21 @@ def get_bprop_softplus(self):
     return bprop
 
 
+@bprop_getters.register(P.Softsign)
+def get_bprop_softsign(self):
+    """Grad definition for `Softsign` operation."""
+    mul = P.Mul()
+    absolute = P.Abs()
+    div = P.Div()
+    square = P.Square()
+
+    def bprop(x, out, dout):
+        dx = mul(dout, div(1, square(1 + absolute(x))))
+        return (dx,)
+
+    return bprop
+
+
 @bprop_getters.register(P.Tanh)
 def get_bprop_tanh(self):
     """Grad definition for `Tanh` operation."""

mindspore/ops/_op_impl/tbe/__init__.py

@@ -122,6 +122,7 @@ from .round import _round_tbe
 from .tanh import _tanh_tbe
 from .tanh_grad import _tanh_grad_tbe
 from .softmax import _softmax_tbe
+from .softsign import _softsign_tbe
 from .softplus import _softplus_tbe
 from .softplus_grad import _softplus_grad_tbe
 from .softmax_grad_ext import _softmax_grad_ext_tbe

mindspore/ops/_op_impl/tbe/softsign.py

@@ -0,0 +1,37 @@
+# Copyright 2020 Huawei Technologies Co., Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ============================================================================
+
+"""Softsign op"""
+from mindspore.ops.op_info_register import op_info_register, TBERegOp, DataType
+
+softsign_op_info = TBERegOp("Softsign") \
+    .fusion_type("OPAQUE") \
+    .async_flag(False) \
+    .binfile_name("softsign.so") \
+    .compute_cost(10) \
+    .kernel_name("softsign") \
+    .partial_flag(True) \
+    .op_pattern("formatAgnostic") \
+    .input(0, "x", False, "required", "all") \
+    .output(0, "y", False, "required", "all") \
+    .dtype_format(DataType.F16_Default, DataType.F16_Default) \
+    .dtype_format(DataType.F32_Default, DataType.F32_Default) \
+    .get_op_info()
+
+
+@op_info_register(softsign_op_info)
+def _softsign_tbe():
+    """Softsign TBE register"""
+    return

mindspore/ops/operations/__init__.py

@@ -68,7 +68,7 @@ from .nn_ops import (LSTM, SGD, Adam, SparseApplyAdam, SparseApplyLazyAdam, Appl
                      MaxPoolWithArgmax, OneHot, Pad, MirrorPad, PReLU, ReLU, ReLU6, ReLUV2, HSwish, HSigmoid,
                      ResizeBilinear, Sigmoid,
                      SigmoidCrossEntropyWithLogits,
-                     SmoothL1Loss, Softmax, Softplus, LRN,
+                     SmoothL1Loss, Softmax, Softsign, Softplus, LRN,
                      SoftmaxCrossEntropyWithLogits, ROIAlign,
                      SparseSoftmaxCrossEntropyWithLogits, Tanh,
                      TopK, BinaryCrossEntropy, SparseApplyAdagrad, LARSUpdate, ApplyFtrl, SparseApplyFtrl,
@@ -115,6 +115,7 @@ __all__ = [
     'SparseApplyLazyAdam',
     'Softplus',
     'Softmax',
+    'Softsign',
     'LogSoftmax',
     'SoftmaxCrossEntropyWithLogits',
     'ROIAlign',

mindspore/ops/operations/nn_ops.py

@@ -224,6 +224,41 @@ class Softplus(PrimitiveWithInfer):
         return input_x
 
 
+class Softsign(PrimitiveWithInfer):
+    r"""
+    Softsign activation function.
+
+    The function is shown as follows:
+
+    .. math::
+        \text{output} = \frac{\text{input_x}}{1 + \abs{\text{input_x}}},
+
+    Inputs:
+        - **input_x** (Tensor) - The input tensor whose data type should be float.
+
+    Outputs:
+        Tensor, with the same type and shape as the `input_x`.
+
+    Examples:
+        >>> input_x = Tensor(np.array([0, -1, 2, 30, -30]), mindspore.float32)
+        >>> softsign = P.Softsign()
+        >>> softsign(input_x)
+        [0. -0.5 0.6666667 0.9677419 -0.9677419]
+    """
+
+    @prim_attr_register
+    def __init__(self):
+        """init Softsign"""
+        self.init_prim_io_names(inputs=['x'], outputs=['output'])
+
+    def infer_shape(self, input_x):
+        return input_x
+
+    def infer_dtype(self, input_x):
+        validator.check_tensor_type_same({'input_x': input_x}, mstype.float_type, self.name)
+        return input_x
+
+
 class ReLU(PrimitiveWithInfer):
     r"""
     Computes ReLU(Rectified Linear Unit) of input tensor element-wise.

tests/ut/python/ops/test_ops.py

@@ -1376,6 +1376,10 @@ test_case_nn_ops = [
         'block': P.Softmax(),
         'desc_inputs': [[5, 5]],
         'desc_bprop': [[5, 5]]}),
+    ('Softsign', {
+        'block': P.Softsign(),
+        'desc_inputs': [[5, 5]],
+        'desc_bprop': [[5, 5]]}),
     ('DepthwiseConv2dNative_1', {
         'block': P.DepthwiseConv2dNative(3, (3, 3), pad_mode="pad", pad=1, stride=2),
         'desc_inputs': [[10, 32, 32, 32], [1, 32, 3, 3]],