[Bug tree-optimization/19624] PRE pessimizes ivopts

[rguenth at tat dot physik dot uni-tuebingen dot de]

------- Additional Comments From rguenth at tat dot physik dot uni-tuebingen dot de  2005-01-25 14:52 -------
Oh, in principle this should compile to roughly the same as

void c_test(double *a, double *b, int ei, int ej, int stridea, int strideb)
{
  for (int j=0; j<ej; ++j)
    for (int i=0; i<ei; ++i)
      a[i+j*stridea] = 0.5*(b[i+1+j*strideb] + b[i+(j+1)*strideb]);
}

... in principle (for the above -fno-tree-pre helps, too).

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19624