chore: import upstream snapshot with attribution

paddle/phi/kernels/cpu/i1e_kernel.cc

@@ -0,0 +1,41 @@
+// Copyright (c) 2023 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.
+
+#include "paddle/phi/kernels/i1e_kernel.h"
+
+#include "paddle/phi/backends/cpu/cpu_context.h"
+#include "paddle/phi/core/kernel_registry.h"
+#include "paddle/phi/kernels/funcs/for_range.h"
+#include "paddle/phi/kernels/impl/bessel_kernel_impl.h"
+
+namespace phi {
+
+template <typename T, typename Context>
+void I1eKernel(const Context& dev_ctx, const DenseTensor& x, DenseTensor* out) {
+  if (out && out->numel() == 0) {
+    dev_ctx.template Alloc<T>(out);
+    return;
+  }
+  const int64_t size = x.numel();
+  const T* x_data = x.data<T>();
+  T* out_data = dev_ctx.template Alloc<T>(out);
+
+  funcs::ForRange<Context> for_range(dev_ctx, size);
+  I1eFunctor<T> functor(x_data, out_data, size);
+  for_range(functor);
+}
+
+}  // namespace phi
+
+PD_REGISTER_KERNEL(i1e, CPU, ALL_LAYOUT, phi::I1eKernel, float, double) {}