[PATCH] tree-optimization/114057 - handle BB reduction remain defs as LIVE

[Richard Biener]

The following makes sure to record the scalars we add to the BB
reduction vectorization result as scalar uses for the purpose of
computing live lanes.  This restores vectorization in the
bondfree.c TU of 435.gromacs.

Bootstrapped and tested on x86_64-unknown-linux-gnu, pushed.

        PR tree-optimization/114057
        * tree-vect-slp.cc (vect_bb_slp_mark_live_stmts): Mark
        BB reduction remain defs as scalar uses.
---
 gcc/tree-vect-slp.cc | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/gcc/tree-vect-slp.cc b/gcc/tree-vect-slp.cc
index adb2d9ae1e5..2e5481acbc7 100644
--- a/gcc/tree-vect-slp.cc
+++ b/gcc/tree-vect-slp.cc
@@ -6665,8 +6665,14 @@ vect_bb_slp_mark_live_stmts (bb_vec_info bb_vinfo)
   auto_vec<slp_tree> worklist;
 
   for (slp_instance instance : bb_vinfo->slp_instances)
-    if (!visited.add (SLP_INSTANCE_TREE (instance)))
-      worklist.safe_push (SLP_INSTANCE_TREE (instance));
+    {
+      if (SLP_INSTANCE_KIND (instance) == slp_inst_kind_bb_reduc)
+       for (tree op : SLP_INSTANCE_REMAIN_DEFS (instance))
+         if (TREE_CODE (op) == SSA_NAME)
+           scalar_use_map.put (op, 1);
+      if (!visited.add (SLP_INSTANCE_TREE (instance)))
+       worklist.safe_push (SLP_INSTANCE_TREE (instance));
+    }
 
   do
     {
@@ -6684,7 +6690,8 @@ vect_bb_slp_mark_live_stmts (bb_vec_info bb_vinfo)
            if (child && !visited.add (child))
              worklist.safe_push (child);
        }
-    } while (!worklist.is_empty ());
+    }
+  while (!worklist.is_empty ());
 
   visited.empty ();
 
-- 
2.35.3