1/*
2 * Copyright (C) 2017 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include "HashtableLookup.h"
18
19#include "CpuExecutor.h"
20#include "HalInterfaces.h"
21#include "Operations.h"
22
23namespace android {
24namespace nn {
25
26namespace {
27
28int greater(const void* a, const void* b) {
29  return *static_cast<const int*>(a) - *static_cast<const int*>(b);
30}
31
32}  // anonymous namespace
33
34HashtableLookup::HashtableLookup(const Operation& operation,
35                                 std::vector<RunTimeOperandInfo>& operands) {
36  lookup_ = GetInput(operation, operands, kLookupTensor);
37  key_ = GetInput(operation, operands, kKeyTensor);
38  value_ = GetInput(operation, operands, kValueTensor);
39
40  output_ = GetOutput(operation, operands, kOutputTensor);
41  hits_ = GetOutput(operation, operands, kHitsTensor);
42}
43
44bool HashtableLookup::Eval() {
45  const int num_rows = value_->shape().dimensions[0];
46  const int row_bytes = sizeOfData(value_->type, value_->dimensions) / num_rows;
47  void* pointer = nullptr;
48
49  for (int i = 0; i < static_cast<int>(lookup_->shape().dimensions[0]); i++) {
50    int idx = -1;
51    pointer = bsearch(lookup_->buffer + sizeof(int) * i, key_->buffer,
52                      num_rows, sizeof(int), greater);
53    if (pointer != nullptr) {
54      idx =
55          (reinterpret_cast<uint8_t*>(pointer) - key_->buffer) / sizeof(float);
56    }
57
58    if (idx >= num_rows || idx < 0) {
59      memset(output_->buffer + i * row_bytes, 0, row_bytes);
60      hits_->buffer[i] = 0;
61    } else {
62      memcpy(output_->buffer + i * row_bytes, value_->buffer + idx * row_bytes,
63             row_bytes);
64      hits_->buffer[i] = 1;
65    }
66  }
67
68  return true;
69}
70
71}  // namespace nn
72}  // namespace android
73