[Bug tree-optimization/120357] [14/15/16 Regression] ICE in vect "error: definition in block 9 does not dominate use in block 3" with early break

[rguenth at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120357

--- Comment #8 from Richard Biener <rguenth at gcc dot gnu.org> ---
The following fixes this.  I'm not 100% convinced but it does seem "obvious"
(but for the "peeled" case we seem to eventually create duplicate COND
reduction IVs?  But possibly we reject this case anyhow).  I'm testing this
now.

diff --git a/gcc/tree-vect-loop.cc b/gcc/tree-vect-loop.cc
index 4af510ff20c..cf5b9f3f979 100644
--- a/gcc/tree-vect-loop.cc
+++ b/gcc/tree-vect-loop.cc
@@ -6029,7 +6029,8 @@ vect_create_epilog_for_reduction (loop_vec_info
loop_vinfo,
       /* Create an induction variable.  */
       gimple_stmt_iterator incr_gsi;
       bool insert_after;
-      vect_iv_increment_position (loop_exit, &incr_gsi, &insert_after);
+      vect_iv_increment_position (LOOP_VINFO_IV_EXIT (loop_vinfo),
+                                 &incr_gsi, &insert_after);
       create_iv (series_vect, PLUS_EXPR, vec_step, NULL_TREE, loop, &incr_gsi,
                 insert_after, &indx_before_incr, &indx_after_incr);