https://gcc.gnu.org/g:fa0f551f3931529d5be72140f5a37ed02d0e0366
commit fa0f551f3931529d5be72140f5a37ed02d0e0366
Author: Richard Biener <rguent...@suse.de>
Date: Fri Sep 29 15:12:54 2023 +0200
Do not account single-lane SLP graphs against discovery limit
The following avoids accounting single-lane SLP to the discovery
limit. Even when raising it the attempt of forming multi-lane SLP
can exhaust the limit before we fall back to single-lane.
* tree-vect-slp.cc (vect_build_slp_tree): Only account
multi-lane SLP to limit.
Diff:
---
gcc/tree-vect-slp.cc | 31 ++++++++++++++++++-------------
1 file changed, 18 insertions(+), 13 deletions(-)
diff --git a/gcc/tree-vect-slp.cc b/gcc/tree-vect-slp.cc
index 66c8fa38979f..3a078b253df5 100644
--- a/gcc/tree-vect-slp.cc
+++ b/gcc/tree-vect-slp.cc
@@ -1725,21 +1725,26 @@ vect_build_slp_tree (vec_info *vinfo,
SLP_TREE_SCALAR_STMTS (res) = stmts;
bst_map->put (stmts.copy (), res);
- if (*limit == 0)
+ /* Single-lane SLP doesn't have the chance of run-away, do not account
+ it to the limit. */
+ if (stmts.length () > 1)
{
- if (dump_enabled_p ())
- dump_printf_loc (MSG_NOTE, vect_location,
- "SLP discovery limit exceeded\n");
- /* Mark the node invalid so we can detect those when still in use
- as backedge destinations. */
- SLP_TREE_SCALAR_STMTS (res) = vNULL;
- SLP_TREE_DEF_TYPE (res) = vect_uninitialized_def;
- res->failed = XNEWVEC (bool, group_size);
- memset (res->failed, 0, sizeof (bool) * group_size);
- memset (matches, 0, sizeof (bool) * group_size);
- return NULL;
+ if (*limit == 0)
+ {
+ if (dump_enabled_p ())
+ dump_printf_loc (MSG_NOTE, vect_location,
+ "SLP discovery limit exceeded\n");
+ /* Mark the node invalid so we can detect those when still in use
+ as backedge destinations. */
+ SLP_TREE_SCALAR_STMTS (res) = vNULL;
+ SLP_TREE_DEF_TYPE (res) = vect_uninitialized_def;
+ res->failed = XNEWVEC (bool, group_size);
+ memset (res->failed, 0, sizeof (bool) * group_size);
+ memset (matches, 0, sizeof (bool) * group_size);
+ return NULL;
+ }
+ --*limit;
}
- --*limit;
if (dump_enabled_p ())
dump_printf_loc (MSG_NOTE, vect_location,
