What is the purpose of this code?

[scuizhibin]

int requestedAlgoCount = CUDNN_CONVOLUTION_FWD_ALGO_COUNT;
int returnedAlgoCount = -1;
cudnnConvolutionFwdAlgoPerf_t fwd_results[2 * requestedAlgoCount];
checkCUDNN(cudnnFindConvolutionForwardAlgorithm(*handle, src_tensor_desc,
filter_desc, conv_desc, dst_tensor_desc, requestedAlgoCount,
&returnedAlgoCount, fwd_results));
fwd_algo = fwd_results[0].algo;