Interface primitive::softmax (#6594)

* interface primitive::softmax

* refine
Co-authored-by: Noneflow-ci-bot <69100618+oneflow-ci-bot@users.noreply.github.com>

oneflow/core/primitive/include/softmax.h

+/*
+Copyright 2020 The OneFlow Authors. All rights reserved.
+
+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.
+*/
+#ifndef ONEFLOW_CORE_PRIMITIVE_SOFTMAX_H_
+#define ONEFLOW_CORE_PRIMITIVE_SOFTMAX_H_
+
+#include "oneflow/core/primitive/include/primitive.h"
+
+namespace oneflow {
+
+namespace primitive {
+
+class Softmax : public Primitive {
+ public:
+  OF_DISALLOW_COPY_AND_MOVE(Softmax);
+  Softmax() = default;
+  ~Softmax() override = default;
+
+  virtual void Launch(StreamContext* stream_ctx, size_t rows, size_t cols, const void* x,
+                      void* y) = 0;
+};
+
+class SoftmaxFactory : public Factory<Softmax> {
+ public:
+  OF_DISALLOW_COPY_AND_MOVE(SoftmaxFactory);
+  SoftmaxFactory() = default;
+  ~SoftmaxFactory() override = default;
+
+  virtual std::unique_ptr<Softmax> New(DataType data_type) = 0;
+};
+
+}  // namespace primitive
+
+}  // namespace oneflow
+
+#endif  // ONEFLOW_CORE_PRIMITIVE_SOFTMAX_H_

oneflow/core/primitive/include/softmax_backward.h

+/*
+Copyright 2020 The OneFlow Authors. All rights reserved.
+
+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.
+*/
+#ifndef ONEFLOW_CORE_PRIMITIVE_SOFTMAX_BACKWARD_H_
+#define ONEFLOW_CORE_PRIMITIVE_SOFTMAX_BACKWARD_H_
+
+#include "oneflow/core/primitive/include/primitive.h"
+
+namespace oneflow {
+
+namespace primitive {
+
+class SoftmaxBackward : public Primitive {
+ public:
+  OF_DISALLOW_COPY_AND_MOVE(SoftmaxBackward);
+  SoftmaxBackward() = default;
+  ~SoftmaxBackward() override = default;
+
+  virtual void Launch(StreamContext* stream_ctx, size_t rows, size_t cols, const void* y,
+                      const void* dy, void* dx) = 0;
+};
+
+class SoftmaxBackwardFactory : public Factory<SoftmaxBackward> {
+ public:
+  OF_DISALLOW_COPY_AND_MOVE(SoftmaxBackwardFactory);
+  SoftmaxBackwardFactory() = default;
+  ~SoftmaxBackwardFactory() override = default;
+
+  virtual std::unique_ptr<SoftmaxBackward> New(DataType data_type) = 0;
+};
+
+}  // namespace primitive
+
+}  // namespace oneflow
+
+#endif  // ONEFLOW_CORE_PRIMITIVE_SOFTMAX_BACKWARD_H_