chore: import upstream snapshot with attribution

paddle/phi/kernels/funcs/math/bert_encoder_functor.h

@@ -0,0 +1,73 @@
+// Copyright (c) 2024 PaddlePaddle 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.
+
+#pragma once
+
+#ifdef PADDLE_WITH_CUDA
+#include <cuda.h>
+#include <cuda_runtime.h>
+#endif
+#ifdef PADDLE_WITH_HIP
+#include <hip/hip_runtime.h>
+#endif
+#include "paddle/phi/backends/all_context.h"
+#include "paddle/phi/kernels/funcs/cub.h"
+
+namespace phi {
+namespace math {
+
+template <typename T>
+struct CUDATypeTraits;
+
+template <>
+struct CUDATypeTraits<half> {
+  typedef phi::float16 TYPE;
+};
+
+template <>
+struct CUDATypeTraits<float> {
+  typedef float TYPE;
+};
+
+#if defined(PADDLE_WITH_CUDA) || defined(PADDLE_WITH_HIP)
+// This functor involves a fusion calculation in Ernie or Bert.
+// The fusion mode is as follows:
+//
+// |           |
+// other_op1   other_op2
+//      |           |
+//      |------elementwise_add
+//                  |
+//              layer_norm
+//                  |
+//              other_op3
+//                  |
+
+template <typename T>
+class SkipLayerNormFunctor {
+ public:
+  void operator()(const int num,
+                  const int hidden,
+                  const T *input1,
+                  const T *input2,
+                  const T *scale,
+                  const T *bias,
+                  T *output,
+                  float eps,
+                  gpuStream_t stream);
+};
+#endif
+
+}  // namespace math
+}  // namespace phi