https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102072
--- Comment #7 from Jiu Fu Guo <guojiufu at gcc dot gnu.org> ---
For this case: it was generated as:
l_12 = l_25 + 1;
if (l_12 > n_13(D))
Here: cmp is ">", bound is "n_13", and "iv(base=l_xx, step=1)".
This hits the assert in determine_exit_conditions.
For members of tree_niter_desc, the comments(as below) align with the asserts
in determine_exit_conditions.
------------
/* The simplified shape of the exit condition. The loop exits if
CONTROL CMP BOUND is false, where CMP is one of NE_EXPR,
LT_EXPR, or GT_EXPR, and step of CONTROL is positive if CMP is
LE_EXPR and negative if CMP is GE_EXPR. This information is used
by loop unrolling. */
affine_iv control;
tree bound;
enum tree_code cmp;
Current code the "control, bound and cmp" are set in number_of_iterations_lt:
if (integer_nonzerop (iv0->step))
{
niter->control = *iv0;
niter->cmp = LT_EXPR;
niter->bound = iv1->base;
}
else
{
niter->control = *iv1;
niter->cmp = GT_EXPR;
niter->bound = iv0->base;
}
This code may need to refine for the case "step until wrap condition".
