[gcc r17-2064] fix: Check if loop_vinfo is null before dereferencing.

[Alfie Richards]

https://gcc.gnu.org/g:470f86dd50a8adedbaa6ae9468bf42bfe89d1a36

commit r17-2064-g470f86dd50a8adedbaa6ae9468bf42bfe89d1a36
Author: Alfie Richards <alfie.richards@arm.com>
Date:   Wed Jul 1 16:01:03 2026 +0000

    fix: Check if loop_vinfo is null before dereferencing.
    
    gcc/ChangeLog:
    
            * tree-vect-loop-manip.cc (vect_set_loop_condition_normal):
            Check if loop_vinfo is null before dereference.

Diff:
---
 gcc/tree-vect-loop-manip.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gcc/tree-vect-loop-manip.cc b/gcc/tree-vect-loop-manip.cc
index ff90a21c8dd2..ec9dec1b7135 100644
--- a/gcc/tree-vect-loop-manip.cc
+++ b/gcc/tree-vect-loop-manip.cc
@@ -1355,7 +1355,7 @@ vect_set_loop_condition_normal (loop_vec_info loop_vinfo, edge exit_edge,
   create_iv (init, PLUS_EXPR, step, NULL_TREE, loop,
 	     &incr_gsi, insert_after,
 	     &indx_before_incr, &indx_after_incr,
-	     LOOP_VINFO_IV_INCREMENT_INVARIANT_P (loop_vinfo));
+	     !loop_vinfo || LOOP_VINFO_IV_INCREMENT_INVARIANT_P (loop_vinfo));
 
   indx_after_incr = force_gimple_operand_gsi (&loop_cond_gsi, indx_after_incr,
 					      true, NULL_TREE, true,