1  /* { dg-do compile } */
       2  /* { dg-additional-options "-Ofast" } */
       3  /* { dg-require-effective-target vect_double } */
       4  
       5  void foo1x1(double* restrict y, const double* restrict x, int clen)
       6  {
       7    int xi = clen & 2;
       8    double f_re = x[0+xi+0];
       9    double f_im = x[4+xi+0];
      10    int clen2 = (clen+xi) * 2;
      11  #pragma GCC unroll 0
      12    for (int c = 0; c < clen2; c += 8) {
      13      // y[c] = y[c] - x[c]*conj(f);
      14  #pragma GCC unroll 4
      15      for (int k = 0; k < 4; ++k) {
      16        double x_re = x[c+0+k];
      17        double x_im = x[c+4+k];
      18        double y_re = y[c+0+k];
      19        double y_im = y[c+4+k];
      20        y_re = y_re - x_re * f_re - x_im * f_im;;
      21        y_im = y_im + x_re * f_im - x_im * f_re;
      22        y[c+0+k] = y_re;
      23        y[c+4+k] = y_im;
      24      }
      25    }
      26  }
      27  
      28  /* { dg-final { scan-tree-dump "vectorizing stmts using SLP" "vect" } } */
      29  /* { dg-final { scan-tree-dump "Loop contains only SLP stmts" "vect" } } */