[Bug tree-optimization/88760] GCC unrolling is suboptimal

[guojiufu at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88760

--- Comment #41 from Jiu Fu Guo <guojiufu at gcc dot gnu.org> ---
for code:

  subroutine foo (i, i1, block)
    integer :: i, i1
    integer :: block(9, 9, 9)
    block(i:9,1,i1) = block(i:9,1,i1) - 10
  end subroutine foo

"-funroll-loops  --param max-unroll-times=2 --param max-unrolled-insns=20"
could help to improve some run time.(~10% on ppcle)

main:
  do n = 0, N
     do i = 1, 9
        do j = 1, 9                                                             
           call foo (i, j, block)
        end do
     end do
  end do