Hi,
my understanding of the code is that trip_count is trying to estimate number
of iterations when counts are available and disable modulo scheduler for
loops with too few iterations.
We now have get_estimated_loop_iterations_int and get_max_loop_iterations_int
which keeps information detected upstream and so we should use i there.
I tested the patch very lightly only on the testcase in question as I am not
sure when and how modulo sched is used.
Seems sane? What are the code size impacts of modulo scheduling?
Honza
PR 82849
* modulo-sched.c (sms_schedule): Use get_estimated_loop_iterations_int
and get_max_loop_iterations_int.
Index: modulo-sched.c
===================================================================
--- modulo-sched.c (revision 254929)
+++ modulo-sched.c (working copy)
@@ -1346,7 +1346,7 @@ sms_schedule (void)
struct loop *loop;
basic_block condition_bb = NULL;
edge latch_edge;
- gcov_type trip_count = 0;
+ HOST_WIDE_INT trip_count, max_trip_count;
loop_optimizer_init (LOOPS_HAVE_PREHEADERS
| LOOPS_HAVE_RECORDED_EXITS);
@@ -1422,9 +1422,8 @@ sms_schedule (void)
get_ebb_head_tail (bb, bb, &head, &tail);
latch_edge = loop_latch_edge (loop);
gcc_assert (single_exit (loop));
- if (single_exit (loop)->count () > profile_count::zero ())
- trip_count = latch_edge->count ().to_gcov_type ()
- / single_exit (loop)->count ().to_gcov_type ();
+ trip_count = get_estimated_loop_iterations_int (loop);
+ max_trip_count = get_max_loop_iterations_int (loop);
/* Perform SMS only on loops that their average count is above
threshold. */
@@ -1444,8 +1443,8 @@ sms_schedule (void)
(int64_t) bb->count.to_gcov_type ());
fprintf (dump_file, "\n");
fprintf (dump_file, "SMS trip-count ");
- fprintf (dump_file, "%" PRId64,
- (int64_t) trip_count);
+ fprintf (dump_file, "%" PRId64 "max %" PRId64,
+ (int64_t) trip_count, (int64_t) max_trip_count);
fprintf (dump_file, "\n");
fprintf (dump_file, "SMS profile-sum-max ");
fprintf (dump_file, "%" PRId64,
@@ -1552,9 +1551,8 @@ sms_schedule (void)
latch_edge = loop_latch_edge (loop);
gcc_assert (single_exit (loop));
- if (single_exit (loop)->count ()> profile_count::zero ())
- trip_count = latch_edge->count ().to_gcov_type ()
- / single_exit (loop)->count ().to_gcov_type ();
+ trip_count = get_estimated_loop_iterations_int (loop);
+ max_trip_count = get_max_loop_iterations_int (loop);
if (dump_file)
{
@@ -1648,7 +1646,8 @@ sms_schedule (void)
we let the scheduling passes do the job in this case. */
if (stage_count < PARAM_VALUE (PARAM_SMS_MIN_SC)
|| (count_init && (loop_count <= stage_count))
- || (flag_branch_probabilities && (trip_count <= stage_count)))
+ || (max_trip_count >= 0 && max_trip_count <= stage_count)
+ || (trip_count >= 0 && trip_count <= stage_count))
{
if (dump_file)
{
@@ -1657,7 +1656,8 @@ sms_schedule (void)
" loop-count=", stage_count);
fprintf (dump_file, "%" PRId64, loop_count);
fprintf (dump_file, ", trip-count=");
- fprintf (dump_file, "%" PRId64, trip_count);
+ fprintf (dump_file, "%" PRId64 "max %" PRId64,
+ (int64_t) trip_count, (int64_t) max_trip_count);
fprintf (dump_file, ")\n");
}
break;
