chore: import upstream snapshot with attribution

paddle/phi/api/include/compat/ATen/ops/empty.h

@@ -0,0 +1,75 @@
+// Copyright (c) 2025 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
+
+#include <ATen/core/Tensor.h>
+#include <c10/core/TensorOptions.h>
+#include <utils/dense_sparse_conversion.h>
+#include <optional>
+#include <string_view>
+
+#include "paddle/phi/api/include/api.h"
+#include "paddle/phi/common/place.h"
+
+namespace at {
+
+inline at::Tensor empty(
+    at::IntArrayRef size,
+    at::TensorOptions options = {},
+    ::std::optional<at::MemoryFormat> memory_format = ::std::nullopt) {
+  PD_CHECK(!(memory_format.has_value() &&
+             memory_format.value() != c10::MemoryFormat::Contiguous),
+           "`MemoryFormat` other than Contiguous is not supported now.");
+  if (options.pinned_memory()) {
+    // Pinning memory is only supported for CPU tensors
+    if (options.has_device() && !options.device().is_cpu()) {
+      PD_THROW(
+          "pin_memory=true requires device to be CPU, but got non-CPU device");
+    }
+    auto dense = paddle::experimental::empty(
+        size._PD_ToPaddleIntArray(),
+        compat::_PD_AtenScalarTypeToPhiDataType(options.dtype()),
+        phi::CPUPlace());
+    dense = dense.copy_to(phi::GPUPinnedPlace(), /*blocking=*/true);
+    return compat::_PD_ConvertToSparseIfNeeded(dense, options.layout());
+  }
+  auto dense = paddle::experimental::empty(
+      size._PD_ToPaddleIntArray(),
+      compat::_PD_AtenScalarTypeToPhiDataType(options.dtype()),
+      options._PD_GetPlace());
+  return compat::_PD_ConvertToSparseIfNeeded(dense, options.layout());
+}
+
+inline at::Tensor empty(at::IntArrayRef size,
+                        ::std::optional<at::ScalarType> dtype,
+                        ::std::optional<at::Layout> layout,
+                        ::std::optional<at::Device> device,
+                        ::std::optional<bool> pin_memory,
+                        ::std::optional<at::MemoryFormat> memory_format) {
+  PD_CHECK(!(memory_format.has_value() &&
+             memory_format.value() != c10::MemoryFormat::Contiguous),
+           "`MemoryFormat` other than Contiguous is not supported now.");
+  auto options =
+      at::TensorOptions()
+          .dtype(dtype.value_or(c10::get_default_dtype_as_scalartype()))
+          .layout(layout)
+          .device(device.value_or(at::kCPU))
+          .pinned_memory(pin_memory);
+  return empty(size, options, memory_format);
+}
+
+#define empty_symint empty  // SymIntArrayRef is same as IntArrayRef
+
+}  // namespace at