Function MLUOP_WIN_API fftTwoStepFactor

kernels/fft/fft.cpp:855–1116

Factors for large radices network. Head info: facbuf[0] = stage_num; facbuf[1] = _n; Stages info: facbuf[5 * stage_num + 0] = r; facbuf[5 * stage_num + 1] = section_num; facbuf[5 * stage_num + 2] = out_stride; facbuf[5 * stage_num + 3] = in_stride; facbuf[5 * stage_num + 4] = small_factors_offset;

// facbuf[5 * stage_num + 3] = in_stride;
// facbuf[5 * stage_num + 4] = small_factors_offset;
mluOpStatus_t MLUOP_WIN_API fftTwoStepFactor(mluOpHandle_t handle,
                                             mluOpFFTPlan_t fft_plan,
                                             const int _n, int *facbuf,
                                             const int is_row_major,
                                             const int factor_type) {
  mluOpStatus_t status = MLUOP_STATUS_SUCCESS;
  int n = _n;
  int r, in_stride, section_num, stage_num = 0, out_stride = 1;

  int large_radix = 1;
  int large_count = 1;
  int small_factors_offset = 22 * 5;
  int max_nram_size = handle->nram_size + REM_FOR_STACK - 32 * 1024;
  while (n > 1) {
    if (is_row_major) {
      if (max_nram_size >= NRAM_SIZE_370) {
        switch (_n) {
          case (200):
            r = 200;
            break;

          case (600):
            r = 600;
            break;

          case (256):
            r = 256;
            break;

          case 1024:
            if (n % 32 == 0) {
              r = 32;
            }
            break;

          case 2048:
            if (n % 64 == 0) {
              r = 64;
            } else if ((n % 32) == 0) {
              r = 32;
            }
            break;

          case 6000:
            if (n % 300 == 0) {
              r = 300;
            } else if ((n % 20) == 0) {
              r = 20;
            }
            break;

          case 7000:
            if (n % 280 == 0) {
              r = 280;
            } else if ((n % 25) == 0) {
              r = 25;
            }
            break;