Re: [patch, fortran, RFC] First steps towards inlining matmul

[Thomas Koenig <tkoenig at netcologne dot de>]

Hi Mikael,

>> Still to do:  Bounds checking (a rather big one),
> ... as you do a front-end to front-end transformation, you get bounds
> checking for free, don't you?

Only partially.

What the patch does is

     integer i,j,k
     c = 0
     do j=0, size(b,2)-1
       do k=0, size(a, 2)-1
         do i=0, size(a, 1)-1
            c(i * stride(c,1) + lbound(c,1), j * stride(c,2) +
lbound(c,2)) =
           c(i * stride(c,1) + lbound(c,1), j * stride(c,2) + lbound(c,2)) +
            a(i * stride(a,1) + lbound(a,1), k * stride(a,2) +
lbound(a,2)) *
            b(k * stride(b,1) + lbound(b,1), j * stride(b,2) + lbound(b,2))
         end do
       end do
     end do

If size(b,2) < size(c,2) or size(a,1) < size(c,1) or
size(a,2) < size(b,1), this will not get caught - no
array bounds violation in the DO loops, but illegal
code nonetheless.

Also, the error message is different, which should also be
changed.

What I would like to add to check before the loop, and then
add a "do not bounds-check" flag to the reference.

	Thomas