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<div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno"> 1</span> <span class="comment">/**</span></div>
<div class="line"><a name="l00002"></a><span class="lineno"> 2</span> <span class="comment"> * Copyright (c) 2015-present, Facebook, Inc.</span></div>
<div class="line"><a name="l00003"></a><span class="lineno"> 3</span> <span class="comment"> * All rights reserved.</span></div>
<div class="line"><a name="l00004"></a><span class="lineno"> 4</span> <span class="comment"> *</span></div>
<div class="line"><a name="l00005"></a><span class="lineno"> 5</span> <span class="comment"> * This source code is licensed under the BSD+Patents license found in the</span></div>
<div class="line"><a name="l00006"></a><span class="lineno"> 6</span> <span class="comment"> * LICENSE file in the root directory of this source tree.</span></div>
<div class="line"><a name="l00007"></a><span class="lineno"> 7</span> <span class="comment"> */</span></div>
<div class="line"><a name="l00008"></a><span class="lineno"> 8</span> </div>
<div class="line"><a name="l00009"></a><span class="lineno"> 9</span> <span class="comment">// Copyright 2004-present Facebook. All Rights Reserved.</span></div>
<div class="line"><a name="l00010"></a><span class="lineno"> 10</span> </div>
<div class="line"><a name="l00011"></a><span class="lineno"> 11</span> <span class="preprocessor">#include "IVFUtils.cuh"</span></div>
<div class="line"><a name="l00012"></a><span class="lineno"> 12</span> <span class="preprocessor">#include "../utils/DeviceUtils.h"</span></div>
<div class="line"><a name="l00013"></a><span class="lineno"> 13</span> <span class="preprocessor">#include "../utils/Limits.cuh"</span></div>
<div class="line"><a name="l00014"></a><span class="lineno"> 14</span> <span class="preprocessor">#include "../utils/Select.cuh"</span></div>
<div class="line"><a name="l00015"></a><span class="lineno"> 15</span> <span class="preprocessor">#include "../utils/StaticUtils.h"</span></div>
<div class="line"><a name="l00016"></a><span class="lineno"> 16</span> <span class="preprocessor">#include "../utils/Tensor.cuh"</span></div>
<div class="line"><a name="l00017"></a><span class="lineno"> 17</span> </div>
<div class="line"><a name="l00018"></a><span class="lineno"> 18</span> <span class="comment">//</span></div>
<div class="line"><a name="l00019"></a><span class="lineno"> 19</span> <span class="comment">// This kernel is split into a separate compilation unit to cut down</span></div>
<div class="line"><a name="l00020"></a><span class="lineno"> 20</span> <span class="comment">// on compile time</span></div>
<div class="line"><a name="l00021"></a><span class="lineno"> 21</span> <span class="comment">//</span></div>
<div class="line"><a name="l00022"></a><span class="lineno"> 22</span> </div>
<div class="line"><a name="l00023"></a><span class="lineno"> 23</span> <span class="keyword">namespace </span>faiss { <span class="keyword">namespace </span>gpu {</div>
<div class="line"><a name="l00024"></a><span class="lineno"> 24</span> </div>
<div class="line"><a name="l00025"></a><span class="lineno"> 25</span> <span class="comment">// This is warp divergence central, but this is really a final step</span></div>
<div class="line"><a name="l00026"></a><span class="lineno"> 26</span> <span class="comment">// and happening a small number of times</span></div>
<div class="line"><a name="l00027"></a><span class="lineno"> 27</span> <span class="keyword">inline</span> __device__ <span class="keywordtype">int</span> binarySearchForBucket(<span class="keywordtype">int</span>* prefixSumOffsets,</div>
<div class="line"><a name="l00028"></a><span class="lineno"> 28</span>  <span class="keywordtype">int</span> size,</div>
<div class="line"><a name="l00029"></a><span class="lineno"> 29</span>  <span class="keywordtype">int</span> val) {</div>
<div class="line"><a name="l00030"></a><span class="lineno"> 30</span>  <span class="keywordtype">int</span> start = 0;</div>
<div class="line"><a name="l00031"></a><span class="lineno"> 31</span>  <span class="keywordtype">int</span> end = size;</div>
<div class="line"><a name="l00032"></a><span class="lineno"> 32</span> </div>
<div class="line"><a name="l00033"></a><span class="lineno"> 33</span>  <span class="keywordflow">while</span> (end - start > 0) {</div>
<div class="line"><a name="l00034"></a><span class="lineno"> 34</span>  <span class="keywordtype">int</span> mid = start + (end - start) / 2;</div>
<div class="line"><a name="l00035"></a><span class="lineno"> 35</span> </div>
<div class="line"><a name="l00036"></a><span class="lineno"> 36</span>  <span class="keywordtype">int</span> midVal = prefixSumOffsets[mid];</div>
<div class="line"><a name="l00037"></a><span class="lineno"> 37</span> </div>
<div class="line"><a name="l00038"></a><span class="lineno"> 38</span>  <span class="comment">// Find the first bucket that we are <=</span></div>
<div class="line"><a name="l00039"></a><span class="lineno"> 39</span>  <span class="keywordflow">if</span> (midVal <= val) {</div>
<div class="line"><a name="l00040"></a><span class="lineno"> 40</span>  start = mid + 1;</div>
<div class="line"><a name="l00041"></a><span class="lineno"> 41</span>  } <span class="keywordflow">else</span> {</div>
<div class="line"><a name="l00042"></a><span class="lineno"> 42</span>  end = mid;</div>
<div class="line"><a name="l00043"></a><span class="lineno"> 43</span>  }</div>
<div class="line"><a name="l00044"></a><span class="lineno"> 44</span>  }</div>
<div class="line"><a name="l00045"></a><span class="lineno"> 45</span> </div>
<div class="line"><a name="l00046"></a><span class="lineno"> 46</span>  <span class="comment">// We must find the bucket that it is in</span></div>
<div class="line"><a name="l00047"></a><span class="lineno"> 47</span>  assert(start != size);</div>
<div class="line"><a name="l00048"></a><span class="lineno"> 48</span> </div>
<div class="line"><a name="l00049"></a><span class="lineno"> 49</span>  <span class="keywordflow">return</span> start;</div>
<div class="line"><a name="l00050"></a><span class="lineno"> 50</span> }</div>
<div class="line"><a name="l00051"></a><span class="lineno"> 51</span> </div>
<div class="line"><a name="l00052"></a><span class="lineno"> 52</span> <span class="keyword">template</span> <<span class="keywordtype">int</span> ThreadsPerBlock,</div>
<div class="line"><a name="l00053"></a><span class="lineno"> 53</span>  <span class="keywordtype">int</span> NumWarpQ,</div>
<div class="line"><a name="l00054"></a><span class="lineno"> 54</span>  <span class="keywordtype">int</span> NumThreadQ,</div>
<div class="line"><a name="l00055"></a><span class="lineno"> 55</span>  <span class="keywordtype">bool</span> Dir></div>
<div class="line"><a name="l00056"></a><span class="lineno"> 56</span> __global__ <span class="keywordtype">void</span></div>
<div class="line"><a name="l00057"></a><span class="lineno"> 57</span> pass2SelectLists(Tensor<float, 2, true> heapDistances,</div>
<div class="line"><a name="l00058"></a><span class="lineno"> 58</span>  Tensor<int, 2, true> heapIndices,</div>
<div class="line"><a name="l00059"></a><span class="lineno"> 59</span>  <span class="keywordtype">void</span>** listIndices,</div>
<div class="line"><a name="l00060"></a><span class="lineno"> 60</span>  Tensor<int, 2, true> prefixSumOffsets,</div>
<div class="line"><a name="l00061"></a><span class="lineno"> 61</span>  Tensor<int, 2, true> topQueryToCentroid,</div>
<div class="line"><a name="l00062"></a><span class="lineno"> 62</span>  <span class="keywordtype">int</span> k,</div>
<div class="line"><a name="l00063"></a><span class="lineno"> 63</span>  IndicesOptions opt,</div>
<div class="line"><a name="l00064"></a><span class="lineno"> 64</span>  Tensor<float, 2, true> outDistances,</div>
<div class="line"><a name="l00065"></a><span class="lineno"> 65</span>  Tensor<long, 2, true> outIndices) {</div>
<div class="line"><a name="l00066"></a><span class="lineno"> 66</span>  constexpr <span class="keywordtype">int</span> kNumWarps = ThreadsPerBlock / kWarpSize;</div>
<div class="line"><a name="l00067"></a><span class="lineno"> 67</span> </div>
<div class="line"><a name="l00068"></a><span class="lineno"> 68</span>  __shared__ <span class="keywordtype">float</span> smemK[kNumWarps * NumWarpQ];</div>
<div class="line"><a name="l00069"></a><span class="lineno"> 69</span>  __shared__ <span class="keywordtype">int</span> smemV[kNumWarps * NumWarpQ];</div>
<div class="line"><a name="l00070"></a><span class="lineno"> 70</span> </div>
<div class="line"><a name="l00071"></a><span class="lineno"> 71</span>  constexpr <span class="keyword">auto</span> kInit = Dir ? kFloatMin : kFloatMax;</div>
<div class="line"><a name="l00072"></a><span class="lineno"> 72</span>  BlockSelect<float, int, Dir, Comparator<float>,</div>
<div class="line"><a name="l00073"></a><span class="lineno"> 73</span>  NumWarpQ, NumThreadQ, ThreadsPerBlock></div>
<div class="line"><a name="l00074"></a><span class="lineno"> 74</span>  heap(kInit, -1, smemK, smemV, k);</div>
<div class="line"><a name="l00075"></a><span class="lineno"> 75</span> </div>
<div class="line"><a name="l00076"></a><span class="lineno"> 76</span>  <span class="keyword">auto</span> queryId = blockIdx.x;</div>
<div class="line"><a name="l00077"></a><span class="lineno"> 77</span>  <span class="keywordtype">int</span> num = heapDistances.getSize(1);</div>
<div class="line"><a name="l00078"></a><span class="lineno"> 78</span>  <span class="keywordtype">int</span> limit = utils::roundDown(num, kWarpSize);</div>
<div class="line"><a name="l00079"></a><span class="lineno"> 79</span> </div>
<div class="line"><a name="l00080"></a><span class="lineno"> 80</span>  <span class="keywordtype">int</span> i = threadIdx.x;</div>
<div class="line"><a name="l00081"></a><span class="lineno"> 81</span>  <span class="keyword">auto</span> heapDistanceStart = heapDistances[queryId];</div>
<div class="line"><a name="l00082"></a><span class="lineno"> 82</span> </div>
<div class="line"><a name="l00083"></a><span class="lineno"> 83</span>  <span class="comment">// BlockSelect add cannot be used in a warp divergent circumstance; we</span></div>
<div class="line"><a name="l00084"></a><span class="lineno"> 84</span>  <span class="comment">// handle the remainder warp below</span></div>
<div class="line"><a name="l00085"></a><span class="lineno"> 85</span>  <span class="keywordflow">for</span> (; i < limit; i += blockDim.x) {</div>
<div class="line"><a name="l00086"></a><span class="lineno"> 86</span>  heap.add(heapDistanceStart[i], i);</div>
<div class="line"><a name="l00087"></a><span class="lineno"> 87</span>  }</div>
<div class="line"><a name="l00088"></a><span class="lineno"> 88</span> </div>
<div class="line"><a name="l00089"></a><span class="lineno"> 89</span>  <span class="comment">// Handle warp divergence separately</span></div>
<div class="line"><a name="l00090"></a><span class="lineno"> 90</span>  <span class="keywordflow">if</span> (i < num) {</div>
<div class="line"><a name="l00091"></a><span class="lineno"> 91</span>  heap.addThreadQ(heapDistanceStart[i], i);</div>
<div class="line"><a name="l00092"></a><span class="lineno"> 92</span>  }</div>
<div class="line"><a name="l00093"></a><span class="lineno"> 93</span> </div>
<div class="line"><a name="l00094"></a><span class="lineno"> 94</span>  <span class="comment">// Merge all final results</span></div>
<div class="line"><a name="l00095"></a><span class="lineno"> 95</span>  heap.reduce();</div>
<div class="line"><a name="l00096"></a><span class="lineno"> 96</span> </div>
<div class="line"><a name="l00097"></a><span class="lineno"> 97</span>  <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i = threadIdx.x; i < k; i += blockDim.x) {</div>
<div class="line"><a name="l00098"></a><span class="lineno"> 98</span>  outDistances[queryId][i] = smemK[i];</div>
<div class="line"><a name="l00099"></a><span class="lineno"> 99</span> </div>
<div class="line"><a name="l00100"></a><span class="lineno"> 100</span>  <span class="comment">// `v` is the index in `heapIndices`</span></div>
<div class="line"><a name="l00101"></a><span class="lineno"> 101</span>  <span class="comment">// We need to translate this into an original user index. The</span></div>
<div class="line"><a name="l00102"></a><span class="lineno"> 102</span>  <span class="comment">// reason why we don't maintain intermediate results in terms of</span></div>
<div class="line"><a name="l00103"></a><span class="lineno"> 103</span>  <span class="comment">// user indices is to substantially reduce temporary memory</span></div>
<div class="line"><a name="l00104"></a><span class="lineno"> 104</span>  <span class="comment">// requirements and global memory write traffic for the list</span></div>
<div class="line"><a name="l00105"></a><span class="lineno"> 105</span>  <span class="comment">// scanning.</span></div>
<div class="line"><a name="l00106"></a><span class="lineno"> 106</span>  <span class="comment">// This code is highly divergent, but it's probably ok, since this</span></div>
<div class="line"><a name="l00107"></a><span class="lineno"> 107</span>  <span class="comment">// is the very last step and it is happening a small number of</span></div>
<div class="line"><a name="l00108"></a><span class="lineno"> 108</span>  <span class="comment">// times (#queries x k).</span></div>
<div class="line"><a name="l00109"></a><span class="lineno"> 109</span>  <span class="keywordtype">int</span> v = smemV[i];</div>
<div class="line"><a name="l00110"></a><span class="lineno"> 110</span>  <span class="keywordtype">long</span> index = -1;</div>
<div class="line"><a name="l00111"></a><span class="lineno"> 111</span> </div>
<div class="line"><a name="l00112"></a><span class="lineno"> 112</span>  <span class="keywordflow">if</span> (v != -1) {</div>
<div class="line"><a name="l00113"></a><span class="lineno"> 113</span>  <span class="comment">// `offset` is the offset of the intermediate result, as</span></div>
<div class="line"><a name="l00114"></a><span class="lineno"> 114</span>  <span class="comment">// calculated by the original scan.</span></div>
<div class="line"><a name="l00115"></a><span class="lineno"> 115</span>  <span class="keywordtype">int</span> offset = heapIndices[queryId][v];</div>
<div class="line"><a name="l00116"></a><span class="lineno"> 116</span> </div>
<div class="line"><a name="l00117"></a><span class="lineno"> 117</span>  <span class="comment">// In order to determine the actual user index, we need to first</span></div>
<div class="line"><a name="l00118"></a><span class="lineno"> 118</span>  <span class="comment">// determine what list it was in.</span></div>
<div class="line"><a name="l00119"></a><span class="lineno"> 119</span>  <span class="comment">// We do this by binary search in the prefix sum list.</span></div>
<div class="line"><a name="l00120"></a><span class="lineno"> 120</span>  <span class="keywordtype">int</span> probe = binarySearchForBucket(prefixSumOffsets[queryId].data(),</div>
<div class="line"><a name="l00121"></a><span class="lineno"> 121</span>  prefixSumOffsets.getSize(1),</div>
<div class="line"><a name="l00122"></a><span class="lineno"> 122</span>  offset);</div>
<div class="line"><a name="l00123"></a><span class="lineno"> 123</span> </div>
<div class="line"><a name="l00124"></a><span class="lineno"> 124</span>  <span class="comment">// This is then the probe for the query; we can find the actual</span></div>
<div class="line"><a name="l00125"></a><span class="lineno"> 125</span>  <span class="comment">// list ID from this</span></div>
<div class="line"><a name="l00126"></a><span class="lineno"> 126</span>  <span class="keywordtype">int</span> listId = topQueryToCentroid[queryId][probe];</div>
<div class="line"><a name="l00127"></a><span class="lineno"> 127</span> </div>
<div class="line"><a name="l00128"></a><span class="lineno"> 128</span>  <span class="comment">// Now, we need to know the offset within the list</span></div>
<div class="line"><a name="l00129"></a><span class="lineno"> 129</span>  <span class="comment">// We ensure that before the array (at offset -1), there is a 0 value</span></div>
<div class="line"><a name="l00130"></a><span class="lineno"> 130</span>  <span class="keywordtype">int</span> listStart = *(prefixSumOffsets[queryId][probe].data() - 1);</div>
<div class="line"><a name="l00131"></a><span class="lineno"> 131</span>  <span class="keywordtype">int</span> listOffset = offset - listStart;</div>
<div class="line"><a name="l00132"></a><span class="lineno"> 132</span> </div>
<div class="line"><a name="l00133"></a><span class="lineno"> 133</span>  <span class="comment">// This gives us our final index</span></div>
<div class="line"><a name="l00134"></a><span class="lineno"> 134</span>  <span class="keywordflow">if</span> (opt == INDICES_32_BIT) {</div>
<div class="line"><a name="l00135"></a><span class="lineno"> 135</span>  index = (long) ((<span class="keywordtype">int</span>*) listIndices[listId])[listOffset];</div>
<div class="line"><a name="l00136"></a><span class="lineno"> 136</span>  } <span class="keywordflow">else</span> <span class="keywordflow">if</span> (opt == INDICES_64_BIT) {</div>
<div class="line"><a name="l00137"></a><span class="lineno"> 137</span>  index = ((<span class="keywordtype">long</span>*) listIndices[listId])[listOffset];</div>
<div class="line"><a name="l00138"></a><span class="lineno"> 138</span>  } <span class="keywordflow">else</span> {</div>
<div class="line"><a name="l00139"></a><span class="lineno"> 139</span>  index = ((long) listId << 32 | (<span class="keywordtype">long</span>) listOffset);</div>
<div class="line"><a name="l00140"></a><span class="lineno"> 140</span>  }</div>
<div class="line"><a name="l00141"></a><span class="lineno"> 141</span>  }</div>
<div class="line"><a name="l00142"></a><span class="lineno"> 142</span> </div>
<div class="line"><a name="l00143"></a><span class="lineno"> 143</span>  outIndices[queryId][i] = index;</div>
<div class="line"><a name="l00144"></a><span class="lineno"> 144</span>  }</div>
<div class="line"><a name="l00145"></a><span class="lineno"> 145</span> }</div>
<div class="line"><a name="l00146"></a><span class="lineno"> 146</span> </div>
<div class="line"><a name="l00147"></a><span class="lineno"> 147</span> <span class="keywordtype">void</span></div>
<div class="line"><a name="l00148"></a><span class="lineno"> 148</span> runPass2SelectLists(Tensor<float, 2, true>& heapDistances,</div>
<div class="line"><a name="l00149"></a><span class="lineno"> 149</span>  Tensor<int, 2, true>& heapIndices,</div>
<div class="line"><a name="l00150"></a><span class="lineno"> 150</span>  thrust::device_vector<void*>& listIndices,</div>
<div class="line"><a name="l00151"></a><span class="lineno"> 151</span>  IndicesOptions indicesOptions,</div>
<div class="line"><a name="l00152"></a><span class="lineno"> 152</span>  Tensor<int, 2, true>& prefixSumOffsets,</div>
<div class="line"><a name="l00153"></a><span class="lineno"> 153</span>  Tensor<int, 2, true>& topQueryToCentroid,</div>
<div class="line"><a name="l00154"></a><span class="lineno"> 154</span>  <span class="keywordtype">int</span> k,</div>
<div class="line"><a name="l00155"></a><span class="lineno"> 155</span>  <span class="keywordtype">bool</span> chooseLargest,</div>
<div class="line"><a name="l00156"></a><span class="lineno"> 156</span>  Tensor<float, 2, true>& outDistances,</div>
<div class="line"><a name="l00157"></a><span class="lineno"> 157</span>  Tensor<long, 2, true>& outIndices,</div>
<div class="line"><a name="l00158"></a><span class="lineno"> 158</span>  cudaStream_t stream) {</div>
<div class="line"><a name="l00159"></a><span class="lineno"> 159</span>  constexpr <span class="keyword">auto</span> kThreadsPerBlock = 128;</div>
<div class="line"><a name="l00160"></a><span class="lineno"> 160</span> </div>
<div class="line"><a name="l00161"></a><span class="lineno"> 161</span>  <span class="keyword">auto</span> grid = dim3(topQueryToCentroid.getSize(0));</div>
<div class="line"><a name="l00162"></a><span class="lineno"> 162</span>  <span class="keyword">auto</span> block = dim3(kThreadsPerBlock);</div>
<div class="line"><a name="l00163"></a><span class="lineno"> 163</span> </div>
<div class="line"><a name="l00164"></a><span class="lineno"> 164</span> <span class="preprocessor">#define RUN_PASS(NUM_WARP_Q, NUM_THREAD_Q, DIR) \</span></div>
<div class="line"><a name="l00165"></a><span class="lineno"> 165</span> <span class="preprocessor"> do { \</span></div>
<div class="line"><a name="l00166"></a><span class="lineno"> 166</span> <span class="preprocessor"> pass2SelectLists<kThreadsPerBlock, \</span></div>
<div class="line"><a name="l00167"></a><span class="lineno"> 167</span> <span class="preprocessor"> NUM_WARP_Q, NUM_THREAD_Q, DIR> \</span></div>
<div class="line"><a name="l00168"></a><span class="lineno"> 168</span> <span class="preprocessor"> <<<grid, block, 0, stream>>>(heapDistances, \</span></div>
<div class="line"><a name="l00169"></a><span class="lineno"> 169</span> <span class="preprocessor"> heapIndices, \</span></div>
<div class="line"><a name="l00170"></a><span class="lineno"> 170</span> <span class="preprocessor"> listIndices.data().get(), \</span></div>
<div class="line"><a name="l00171"></a><span class="lineno"> 171</span> <span class="preprocessor"> prefixSumOffsets, \</span></div>
<div class="line"><a name="l00172"></a><span class="lineno"> 172</span> <span class="preprocessor"> topQueryToCentroid, \</span></div>
<div class="line"><a name="l00173"></a><span class="lineno"> 173</span> <span class="preprocessor"> k, \</span></div>
<div class="line"><a name="l00174"></a><span class="lineno"> 174</span> <span class="preprocessor"> indicesOptions, \</span></div>
<div class="line"><a name="l00175"></a><span class="lineno"> 175</span> <span class="preprocessor"> outDistances, \</span></div>
<div class="line"><a name="l00176"></a><span class="lineno"> 176</span> <span class="preprocessor"> outIndices); \</span></div>
<div class="line"><a name="l00177"></a><span class="lineno"> 177</span> <span class="preprocessor"> CUDA_TEST_ERROR(); \</span></div>
<div class="line"><a name="l00178"></a><span class="lineno"> 178</span> <span class="preprocessor"> return; </span><span class="comment">/* success */</span><span class="preprocessor"> \</span></div>
<div class="line"><a name="l00179"></a><span class="lineno"> 179</span> <span class="preprocessor"> } while (0)</span></div>
<div class="line"><a name="l00180"></a><span class="lineno"> 180</span> <span class="preprocessor"></span></div>
<div class="line"><a name="l00181"></a><span class="lineno"> 181</span> <span class="preprocessor">#define RUN_PASS_DIR(DIR) \</span></div>
<div class="line"><a name="l00182"></a><span class="lineno"> 182</span> <span class="preprocessor"> do { \</span></div>
<div class="line"><a name="l00183"></a><span class="lineno"> 183</span> <span class="preprocessor"> if (k == 1) { \</span></div>
<div class="line"><a name="l00184"></a><span class="lineno"> 184</span> <span class="preprocessor"> RUN_PASS(1, 1, DIR); \</span></div>
<div class="line"><a name="l00185"></a><span class="lineno"> 185</span> <span class="preprocessor"> } else if (k <= 32) { \</span></div>
<div class="line"><a name="l00186"></a><span class="lineno"> 186</span> <span class="preprocessor"> RUN_PASS(32, 2, DIR); \</span></div>
<div class="line"><a name="l00187"></a><span class="lineno"> 187</span> <span class="preprocessor"> } else if (k <= 64) { \</span></div>
<div class="line"><a name="l00188"></a><span class="lineno"> 188</span> <span class="preprocessor"> RUN_PASS(64, 3, DIR); \</span></div>
<div class="line"><a name="l00189"></a><span class="lineno"> 189</span> <span class="preprocessor"> } else if (k <= 128) { \</span></div>
<div class="line"><a name="l00190"></a><span class="lineno"> 190</span> <span class="preprocessor"> RUN_PASS(128, 3, DIR); \</span></div>
<div class="line"><a name="l00191"></a><span class="lineno"> 191</span> <span class="preprocessor"> } else if (k <= 256) { \</span></div>
<div class="line"><a name="l00192"></a><span class="lineno"> 192</span> <span class="preprocessor"> RUN_PASS(256, 4, DIR); \</span></div>
<div class="line"><a name="l00193"></a><span class="lineno"> 193</span> <span class="preprocessor"> } else if (k <= 512) { \</span></div>
<div class="line"><a name="l00194"></a><span class="lineno"> 194</span> <span class="preprocessor"> RUN_PASS(512, 8, DIR); \</span></div>
<div class="line"><a name="l00195"></a><span class="lineno"> 195</span> <span class="preprocessor"> } else if (k <= 1024) { \</span></div>
<div class="line"><a name="l00196"></a><span class="lineno"> 196</span> <span class="preprocessor"> RUN_PASS(1024, 8, DIR); \</span></div>
<div class="line"><a name="l00197"></a><span class="lineno"> 197</span> <span class="preprocessor"> } \</span></div>
<div class="line"><a name="l00198"></a><span class="lineno"> 198</span> <span class="preprocessor"> } while (0)</span></div>
<div class="line"><a name="l00199"></a><span class="lineno"> 199</span> <span class="preprocessor"></span></div>
<div class="line"><a name="l00200"></a><span class="lineno"> 200</span>  <span class="keywordflow">if</span> (chooseLargest) {</div>
<div class="line"><a name="l00201"></a><span class="lineno"> 201</span>  RUN_PASS_DIR(<span class="keyword">true</span>);</div>
<div class="line"><a name="l00202"></a><span class="lineno"> 202</span>  } <span class="keywordflow">else</span> {</div>
<div class="line"><a name="l00203"></a><span class="lineno"> 203</span>  RUN_PASS_DIR(<span class="keyword">false</span>);</div>
<div class="line"><a name="l00204"></a><span class="lineno"> 204</span>  }</div>
<div class="line"><a name="l00205"></a><span class="lineno"> 205</span> </div>
<div class="line"><a name="l00206"></a><span class="lineno"> 206</span>  <span class="comment">// unimplemented / too many resources</span></div>
<div class="line"><a name="l00207"></a><span class="lineno"> 207</span>  FAISS_ASSERT_FMT(<span class="keyword">false</span>, <span class="stringliteral">"unimplemented k value (%d)"</span>, k);</div>
<div class="line"><a name="l00208"></a><span class="lineno"> 208</span> </div>
<div class="line"><a name="l00209"></a><span class="lineno"> 209</span> <span class="preprocessor">#undef RUN_PASS_DIR</span></div>
<div class="line"><a name="l00210"></a><span class="lineno"> 210</span> <span class="preprocessor"></span><span class="preprocessor">#undef RUN_PASS</span></div>
<div class="line"><a name="l00211"></a><span class="lineno"> 211</span> <span class="preprocessor"></span>}</div>
<div class="line"><a name="l00212"></a><span class="lineno"> 212</span> </div>
<div class="line"><a name="l00213"></a><span class="lineno"> 213</span> } } <span class="comment">// namespace</span></div>
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