From: Richard Biener <rguenther@suse.de>
Date: Fri, 28 Jun 2024 11:29:21 +0000 (+0200)
Subject: tree-optimization/115652 - more fixing of the fix
X-Git-Tag: basepoints/gcc-16~7844
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ff6e8b7f09712bd7ddfcd2830b286421f23abef9;p=thirdparty%2Fgcc.git

tree-optimization/115652 - more fixing of the fix

The following addresses the corner case of an outer loop with an empty
header where we end up asking for the BB of a NULL stmt by
special-casing this case.

	PR tree-optimization/115652
	* tree-vect-slp.cc (vect_schedule_slp_node): Handle the case
	where the outer loop header block is empty.
---

diff --git a/gcc/tree-vect-slp.cc b/gcc/tree-vect-slp.cc
index 174b4800fa9..dd9017e5b3a 100644
--- a/gcc/tree-vect-slp.cc
+++ b/gcc/tree-vect-slp.cc
@@ -9750,8 +9750,15 @@ vect_schedule_slp_node (vec_info *vinfo,
 	      {
 		gimple_stmt_iterator si2
 		  = gsi_after_labels (LOOP_VINFO_LOOP (loop_vinfo)->header);
-		if (last_stmt != *si2
-		    && vect_stmt_dominates_stmt_p (last_stmt, *si2))
+		if ((gsi_end_p (si2)
+		     && (LOOP_VINFO_LOOP (loop_vinfo)->header
+			 != gimple_bb (last_stmt))
+		     && dominated_by_p (CDI_DOMINATORS,
+					LOOP_VINFO_LOOP (loop_vinfo)->header,
+					gimple_bb (last_stmt)))
+		    || (!gsi_end_p (si2)
+			&& last_stmt != *si2
+			&& vect_stmt_dominates_stmt_p (last_stmt, *si2)))
 		  si = si2;
 	      }
 	}