chore: import upstream snapshot with attribution

paddle/phi/kernels/is_empty_kernel.cc

@@ -0,0 +1,55 @@
+// 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/is_empty_kernel.h"
+
+#include "paddle/phi/backends/all_context.h"
+#include "paddle/phi/core/kernel_registry.h"
+
+namespace phi {
+
+template <typename T, typename Context>
+void IsEmptyKernel(const Context& dev_ctx,
+                   const DenseTensor& x,
+                   DenseTensor* out) {
+  // Note: is_empty is always executed on CPU and the output data should
+  // always be allocated for CPUPlace. We register CUDA kernel for this op to
+  // avoid the unnecessary data transform.
+  bool* out_data = dev_ctx.template HostAlloc<bool>(out);
+  out_data[0] = common::product(x.dims()) == 0;
+}
+
+}  // namespace phi
+
+PD_REGISTER_KERNEL(is_empty,
+                   CPU,
+                   ALL_LAYOUT,
+                   phi::IsEmptyKernel,
+                   float,
+                   double,
+                   int,
+                   int64_t) {
+  kernel->OutputAt(0).SetDataType(phi::DataType::BOOL);
+}
+
+#if defined(PADDLE_WITH_CUDA) || defined(PADDLE_WITH_HIP)
+PD_REGISTER_KERNEL(is_empty,
+                   GPU,
+                   ALL_LAYOUT,
+                   phi::IsEmptyKernel,
+                   float,
+                   double,
+                   int,
+                   int64_t) {}
+#endif