static bool
remove_redundant_iv_tests (struct loop *loop)
{
struct nb_iter_bound *elt;
bool changed = false;
if (!loop->any_upper_bound)
return false;
for (elt = loop->bounds; elt; elt = elt->next)
{
/* Exit is pointless if it won't be taken before loop reaches
upper bound. */
if (elt->is_exit && loop->any_upper_bound
&& wi::ltu_p (loop->nb_iterations_upper_bound, elt->bound))
{
basic_block bb = gimple_bb (elt->stmt);
edge exit_edge = EDGE_SUCC (bb, 0);
struct tree_niter_desc niter;
if (!loop_exit_edge_p (loop, exit_edge))
exit_edge = EDGE_SUCC (bb, 1);
/* Only when we know the actual number of iterations, not
just a bound, we can remove the exit. */
if (!number_of_iterations_exit (loop, exit_edge,
&niter, false, false)
|| !integer_onep (niter.assumptions)
|| !integer_zerop (niter.may_be_zero)
|| !niter.niter
|| TREE_CODE (niter.niter) != INTEGER_CST
|| !wi::ltu_p (loop->nb_iterations_upper_bound,
wi::to_widest (niter.niter)))
continue;
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, "Removed pointless exit: ");
print_gimple_stmt (dump_file, elt->stmt, 0, 0);
}
gcond *cond_stmt = as_a <gcond *> (elt->stmt);
if (exit_edge->flags & EDGE_TRUE_VALUE)
gimple_cond_make_false (cond_stmt);
else
gimple_cond_make_true (cond_stmt);
update_stmt (cond_stmt);
changed = true;
}
}
return changed;
}
static bool
graphite_can_represent_loop (basic_block scop_entry, loop_p loop)
{
tree niter;
struct tree_niter_desc niter_desc;
/* FIXME: For the moment, graphite cannot be used on loops that
iterate using induction variables that wrap. */
return number_of_iterations_exit (loop, single_exit (loop), &niter_desc, false)
&& niter_desc.control.no_overflow
&& (niter = number_of_latch_executions (loop))
&& !chrec_contains_undetermined (niter)
&& graphite_can_represent_expr (scop_entry, loop, niter);
}
