chore: import upstream snapshot with attribution

paddle/phi/kernels/stride/slice_kernel.cc

@@ -0,0 +1,110 @@
+// 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/slice_kernel.h"
+
+#include "glog/logging.h"
+
+#include "paddle/common/flags.h"
+#include "paddle/phi/backends/all_context.h"
+#include "paddle/phi/core/kernel_registry.h"
+#include "paddle/phi/kernels/funcs/slice_utils.h"
+
+COMMON_DECLARE_bool(use_stride_kernel);
+
+namespace phi {
+
+template <typename Context>
+void SliceStridedKernel(const Context& dev_ctx,
+                        const DenseTensor& input,
+                        const std::vector<int64_t>& axes,
+                        const IntArray& starts_arr,
+                        const IntArray& ends_arr,
+                        const std::vector<int64_t>& infer_flags,
+                        const std::vector<int64_t>& decrease_axis,
+                        DenseTensor* out) {
+  if (!FLAGS_use_stride_kernel) {
+    PADDLE_THROW(common::errors::Fatal(
+        "FLAGS_use_stride_kernel is closed. Strided kernel "
+        "be called, something wrong has happened!"));
+  }
+  std::vector<int64_t> starts = starts_arr.GetData();
+  std::vector<int64_t> ends = ends_arr.GetData();
+  const auto& in_dims = input.dims();
+
+  auto new_axes = axes;
+  for (auto& item : new_axes) {
+    if (item < 0) {
+      item = std::max(int64_t(0), item + int64_t(in_dims.size()));
+    }
+  }
+  // axis = 0, dim_value = 3, st[0]=0, ed[0]=4
+  // The step seems to be regarded as 1 here
+  funcs::CheckAndUpdateSliceAttrs<int64_t>(
+      in_dims, new_axes, &starts, &ends, nullptr, nullptr);
+
+  std::vector<int64_t> output_dims = vectorize<int64_t>(input.dims());
+  std::vector<int64_t> output_stride = vectorize<int64_t>(input.strides());
+  int64_t output_offset = static_cast<int64_t>(input.offset());
+
+  for (size_t i = 0; i < new_axes.size(); ++i) {
+    output_offset = static_cast<int64_t>(
+        output_offset +
+        starts[i] * output_stride[new_axes[i]] * SizeOf(out->dtype()));
+    output_dims[new_axes[i]] = std::abs(ends[i] - starts[i]);
+  }
+
+  std::vector<uint8_t> decrease_flag(output_dims.size(), 0);
+  if (!decrease_axis.empty()) {
+    for (auto axis : decrease_axis) {
+      decrease_flag[axis] = 1;
+    }
+
+    std::vector<int64_t> new_shape;
+    std::vector<int64_t> new_stride;
+    for (size_t i = 0; i < output_dims.size(); ++i) {
+      if (decrease_flag[i] == 0) {
+        new_shape.push_back(output_dims[i]);
+        new_stride.push_back(output_stride[i]);
+      }
+    }
+    output_dims = new_shape;
+    output_stride = new_stride;
+  }
+
+  auto meta = out->meta();
+  meta.offset = output_offset;
+  auto tmp_dim = DDim(output_dims.data(), static_cast<int>(output_dims.size()));
+  // if (product(meta.dims) > 0 && meta.dims != tmp_dim) {
+  //   PADDLE_THROW(
+  //       common::errors::Fatal("Slice kernel stride compute diff, infer shape
+  //       is
+  //       "
+  //                          "%s, but compute is %s.",
+  //                          meta.dims,
+  //                          tmp_dim));
+  // }
+  meta.dims = tmp_dim;
+  meta.strides =
+      DDim(output_stride.data(), static_cast<int>(output_stride.size()));
+  out->set_meta(meta);
+  out->ResetHolder(input.Holder());
+  out->ShareInplaceVersionCounterWith(input);
+}
+
+}  // namespace phi
+
+PD_REGISTER_KERNEL_FOR_ALL_BACKEND_DTYPE(slice,
+                                         STRIDED,
+                                         phi::SliceStridedKernel) {}