--- /dev/null
+/*
+ * Copyright (c) 2018 Samsung Electronics Co., Ltd. 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 "support/tflite/kernels/TensorFlowSum.h"
+#include "tensorflow/contrib/lite/kernels/kernel_util.h"
+
+#include <iostream>
+
+namespace tflite
+{
+namespace ops
+{
+namespace custom
+{
+namespace nnfw
+{
+namespace TensorFlowSum
+{
+
+struct TensorFlowSumOp
+{
+ TensorFlowSumOp(TfLiteContext *context, TfLiteNode *node)
+ {
+ input = tflite::GetInput(context, node, 0);
+ axis = tflite::GetInput(context, node, 1);
+ output = tflite::GetOutput(context, node, 0);
+ }
+ const TfLiteTensor *input;
+ const TfLiteTensor *axis;
+ TfLiteTensor *output;
+};
+
+void *InitTensorFlowSum(TfLiteContext *context, const char *buffer, size_t length)
+{
+ // Creates two temp tensors to store index and axis for internal
+ // implementation only.
+ auto *scratch_tensor_index = new int;
+ context->AddTensors(context, 2, scratch_tensor_index);
+ return scratch_tensor_index;
+}
+
+void FreeTensorFlowSum(TfLiteContext *context, void *buffer)
+{
+ delete static_cast<TensorFlowSumOp *>(buffer);
+}
+
+// Resizes the temp tensor that stores resolved axis.
+TfLiteStatus ResizeTempAxis(TfLiteContext *context, TensorFlowSumOp *op_context,
+ TfLiteTensor *resolved_axis)
+{
+ TfLiteIntArray *axis_size = TfLiteIntArrayCreate(1);
+ axis_size->data[0] = static_cast<int>(tflite::NumElements(op_context->axis));
+ return context->ResizeTensor(context, resolved_axis, axis_size);
+}
+
+// Resizes output array based on the input size and resolved axis.
+TfLiteStatus ResizeOutputTensor(TfLiteContext *context, TensorFlowSumOp *op_context)
+{
+ size_t num_axis = tflite::NumElements(op_context->axis);
+ const TfLiteIntArray *input_dims = op_context->input->dims;
+ int input_num_dims = tflite::NumDimensions(op_context->input);
+ const int *axis = op_context->axis->data.i32;
+
+ {
+ // Calculates size of reducing axis.
+ int num_reduce_axis = num_axis;
+ for (int i = 0; i < num_axis; ++i)
+ {
+ int current = axis[i];
+ if (current < 0)
+ {
+ current += input_num_dims;
+ }
+ TF_LITE_ENSURE(context, current >= 0 && current < input_num_dims);
+ for (int j = 0; j < i; ++j)
+ {
+ int previous = axis[j];
+ if (previous < 0)
+ {
+ previous += input_num_dims;
+ }
+ if (current == previous)
+ {
+ --num_reduce_axis;
+ break;
+ }
+ }
+ }
+ // Determines output dimensions.
+ TfLiteIntArray *output_dims = TfLiteIntArrayCreate(input_num_dims - num_reduce_axis);
+ int num_skip_axis = 0;
+ for (int idx = 0; idx < input_num_dims; ++idx)
+ {
+ bool is_axis = false;
+ for (int axis_idx = 0; axis_idx < num_axis; ++axis_idx)
+ {
+ if (axis[axis_idx] == idx || axis[axis_idx] + input_num_dims == idx)
+ {
+ ++num_skip_axis;
+ is_axis = true;
+ break;
+ }
+ }
+ if (!is_axis)
+ {
+ output_dims->data[idx - num_skip_axis] = input_dims->data[idx];
+ }
+ }
+ return context->ResizeTensor(context, op_context->output, output_dims);
+ }
+}
+
+// Initializes temp tensors to store index and resolved axis.
+TfLiteStatus InitializeTemporaries(TfLiteContext *context, TfLiteNode *node,
+ TensorFlowSumOp *op_context)
+{
+ // Creates a temp index to iterate through input data.
+ int *scratch_tensor_index = reinterpret_cast<int *>(node->user_data);
+ TfLiteIntArrayFree(node->temporaries);
+ node->temporaries = TfLiteIntArrayCreate(2);
+ node->temporaries->data[0] = *scratch_tensor_index;
+ TfLiteTensor *scratch_tensor = &context->tensors[node->temporaries->data[0]];
+ scratch_tensor->type = kTfLiteInt32;
+ scratch_tensor->allocation_type = kTfLiteArenaRw;
+ TfLiteIntArray *index_size = TfLiteIntArrayCreate(1);
+ index_size->data[0] = tflite::NumDimensions(op_context->input);
+ TF_LITE_ENSURE_OK(context, context->ResizeTensor(context, scratch_tensor, index_size));
+
+ // Creates a temp tensor to store resolved axis given input data.
+ node->temporaries->data[1] = *scratch_tensor_index + 1;
+ TfLiteTensor *resolved_axis = &context->tensors[node->temporaries->data[1]];
+ resolved_axis->type = kTfLiteInt32;
+ return kTfLiteOk;
+}
+
+TfLiteStatus PrepareTensorFlowSum(TfLiteContext *context, TfLiteNode *node)
+{
+ TF_LITE_ENSURE_EQ(context, tflite::NumInputs(node), 2);
+ TF_LITE_ENSURE_EQ(context, tflite::NumOutputs(node), 1);
+
+ TensorFlowSumOp op_context(context, node);
+ TF_LITE_ENSURE_OK(context, InitializeTemporaries(context, node, &op_context));
+
+ TfLiteTensor *resolved_axis = &context->tensors[node->temporaries->data[1]];
+ // Leaves work to Eval if axis is not constant; else resizes output.
+ if (!tflite::IsConstantTensor(op_context.axis))
+ {
+ tflite::SetTensorToDynamic(op_context.output);
+ tflite::SetTensorToDynamic(resolved_axis);
+ return kTfLiteOk;
+ }
+ resolved_axis->allocation_type = kTfLiteArenaRw;
+ TF_LITE_ENSURE_OK(context, ResizeTempAxis(context, &op_context, resolved_axis));
+ return ResizeOutputTensor(context, &op_context);
+}
+
+// Gets offset of index if expanded on axis. When expanded, the flattened offset
+// will not change, if the output index changes on the given axis. For example,
+// if you have a 2D tensor and you are expanding to 3D on axis 0,
+// then index (0, 1, 2) and index (1, 1, 2) will map from the same flattened
+// offset.
+inline size_t ExpandedInputOffset(const int num_dims, const int *dims, const int *index,
+ const int num_axis, const int *axis)
+{
+ size_t offset = 0;
+ int out_idx = 0;
+ for (int in_idx = 0; in_idx < num_dims; ++in_idx)
+ {
+ // if we need to expand this axis
+ bool is_axis = false;
+ if (axis != nullptr)
+ {
+ for (int axis_idx = 0; axis_idx < num_axis; ++axis_idx)
+ {
+ if (in_idx == axis[axis_idx])
+ {
+ is_axis = true;
+ break;
+ }
+ }
+ }
+ if (!is_axis)
+ {
+ offset = offset * static_cast<size_t>(dims[in_idx]) + static_cast<size_t>(index[out_idx]);
+ out_idx++;
+ }
+ else
+ {
+ offset = offset * static_cast<size_t>(dims[in_idx]);
+ }
+ }
+ return offset;
+}
+
+// Gets offset of index if reducing on axis. When reducing, the flattened offset
+// will not change, if the input index changes on the given axis. For example,
+// if you have a 3D tensor and you are reducing to 2D by eliminating axis 0,
+// then index (0, 1, 2) and index (1, 1, 2) will map to the same flattened
+// offset.
+// TODO(kanlig): uses Dims to represent dimensions.
+inline size_t ReducedOutputOffset(const int num_dims, const int *dims, const int *index,
+ const int num_axis, const int *axis)
+{
+ size_t offset = 0;
+ for (int idx = 0; idx < num_dims; ++idx)
+ {
+ // if we need to skip this axis
+ bool is_axis = false;
+ if (axis != nullptr)
+ {
+ for (int axis_idx = 0; axis_idx < num_axis; ++axis_idx)
+ {
+ if (idx == axis[axis_idx])
+ {
+ is_axis = true;
+ break;
+ }
+ }
+ }
+ if (!is_axis)
+ {
+ offset = offset * static_cast<size_t>(dims[idx]) + static_cast<size_t>(index[idx]);
+ }
+ }
+ return offset;
+}
+
+// Gets next index to iterate through a multidimensional array.
+inline bool NextIndex(TfLiteContext *context, const int num_dims, const int *dims, int *current)
+{
+ int carry = 1;
+ for (int idx = num_dims - 1; idx >= 0; --idx)
+ {
+ int current_val = current[idx] + carry;
+ TF_LITE_ENSURE(context, (dims[idx] >= current_val));
+ if (dims[idx] == current_val)
+ {
+ current[idx] = 0;
+ }
+ else
+ {
+ current[idx] = current_val;
+ carry = 0;
+ break;
+ }
+ }
+ return (carry == 0);
+}
+
+template <typename T>
+inline TfLiteStatus
+CustomSum(TfLiteContext *context, T *input_data, const int *input_dims, const int input_num_dims,
+ T *output_data, const int *output_dims, const int output_num_dims, const int *axis,
+ const int num_axis_dimensions, bool keep_dims, int *temp_index, int *resolved_axis)
+{
+ // resolves axis.
+ int num_resolved_axis = 0;
+ for (int idx = 0; idx < num_axis_dimensions; ++idx)
+ {
+ int current = axis[idx];
+ TF_LITE_ENSURE(context, (current < input_num_dims && current + input_num_dims >= 0));
+ if (current < 0)
+ {
+ current += input_num_dims;
+ }
+ bool is_dup = false;
+ for (int j = 0; j < num_resolved_axis; ++j)
+ {
+ if (resolved_axis[j] == current)
+ {
+ is_dup = true;
+ break;
+ }
+ }
+ if (!is_dup)
+ {
+ resolved_axis[num_resolved_axis++] = current;
+ }
+ }
+
+ TF_LITE_ENSURE(context, (input_num_dims > 0));
+ TF_LITE_ENSURE(context, (input_dims != nullptr));
+ TF_LITE_ENSURE(context, (temp_index != nullptr));
+
+ // resets output data.
+ for (int idx = 0; idx < output_num_dims; ++idx)
+ {
+ temp_index[idx] = 0;
+ }
+ for (bool has_next = true; has_next;
+ has_next = NextIndex(context, output_num_dims, output_dims, temp_index))
+ {
+ size_t output_offset =
+ ReducedOutputOffset(output_num_dims, output_dims, temp_index, 0, nullptr);
+ output_data[output_offset] = 0;
+ }
+
+ // resets temp index.
+ for (int idx = 0; idx < input_num_dims; ++idx)
+ {
+ temp_index[idx] = 0;
+ }
+
+ // iterates through input_data.
+ for (bool has_next = true; has_next;
+ has_next = NextIndex(context, input_num_dims, input_dims, temp_index))
+ {
+ size_t input_offset = ReducedOutputOffset(input_num_dims, input_dims, temp_index, 0, nullptr);
+ size_t output_offset = ReducedOutputOffset(input_num_dims, input_dims, temp_index,
+ num_resolved_axis, resolved_axis);
+ output_data[output_offset] += input_data[input_offset];
+ }
+
+ return kTfLiteOk;
+}
+
+TfLiteStatus EvalTensorFlowSum(TfLiteContext *context, TfLiteNode *node)
+{
+
+ TensorFlowSumOp op_context(context, node);
+ int num_axis = static_cast<int>(tflite::NumElements(op_context.axis));
+ TfLiteTensor *temp_index = &context->tensors[node->temporaries->data[0]];
+ TfLiteTensor *resolved_axis = &context->tensors[node->temporaries->data[1]];
+ // Resize the output tensor if the output tensor is dynamic.
+ if (tflite::IsDynamicTensor(op_context.output))
+ {
+ TF_LITE_ENSURE_OK(context, ResizeTempAxis(context, &op_context, resolved_axis));
+ TF_LITE_ENSURE_OK(context, ResizeOutputTensor(context, &op_context));
+ }
+
+ TfLiteStatus returnStatus = kTfLiteOk;
+ switch (op_context.input->type)
+ {
+ case kTfLiteFloat32:
+ returnStatus = CustomSum<float>(
+ context, op_context.input->data.f, op_context.input->dims->data,
+ op_context.input->dims->size, op_context.output->data.f, op_context.output->dims->data,
+ op_context.output->dims->size, op_context.axis->data.i32, num_axis, false,
+ temp_index->data.i32, resolved_axis->data.i32);
+ break;
+ case kTfLiteInt32:
+ returnStatus = CustomSum<int>(context, op_context.input->data.i32,
+ op_context.input->dims->data, op_context.input->dims->size,
+ op_context.output->data.i32, op_context.output->dims->data,
+ op_context.output->dims->size, op_context.axis->data.i32,
+ num_axis, false, temp_index->data.i32, resolved_axis->data.i32);
+ break;
+ case kTfLiteUInt8:
+ returnStatus = CustomSum<uint8_t>(
+ context, op_context.input->data.uint8, op_context.input->dims->data,
+ op_context.input->dims->size, op_context.output->data.uint8,
+ op_context.output->dims->data, op_context.output->dims->size, op_context.axis->data.i32,
+ num_axis, false, temp_index->data.i32, resolved_axis->data.i32);
+ break;
+ case kTfLiteInt64:
+ returnStatus = CustomSum<int64_t>(
+ context, op_context.input->data.i64, op_context.input->dims->data,
+ op_context.input->dims->size, op_context.output->data.i64, op_context.output->dims->data,
+ op_context.output->dims->size, op_context.axis->data.i32, num_axis, false,
+ temp_index->data.i32, resolved_axis->data.i32);
+ break;
+ default:
+ returnStatus = kTfLiteError;
+ }
+
+ return returnStatus;
+}
+} // namespace TensorFlowSum
+} // namespace nnfw
+} // namespace custom
+} // namespace ops
+} // namespace tflite