chore: import upstream snapshot with attribution

paddle/phi/kernels/dist_kernel.cc

@@ -0,0 +1,40 @@
+// Copyright (c) 2022 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/dist_kernel.h"
+
+#include "paddle/phi/backends/cpu/cpu_context.h"
+#include "paddle/phi/core/kernel_registry.h"
+#include "paddle/phi/kernels/elementwise_subtract_kernel.h"
+#include "paddle/phi/kernels/full_kernel.h"
+#include "paddle/phi/kernels/p_norm_kernel.h"
+namespace phi {
+
+template <typename T, typename Context>
+void DistKernel(const Context& dev_ctx,
+                const DenseTensor& x,
+                const DenseTensor& y,
+                float p,
+                DenseTensor* out) {
+  if (x.numel() == 0 || y.numel() == 0) {
+    Full<T, Context>(dev_ctx, out->dims(), 0, out);
+    return;
+  }
+  auto t = Subtract<T, Context>(dev_ctx, x, y);
+  PNormKernel<T, Context>(dev_ctx, t, p, -1, 1e-12, false, true, out);
+}
+
+}  // namespace phi
+
+PD_REGISTER_KERNEL(dist, CPU, ALL_LAYOUT, phi::DistKernel, float, double) {}