Change both vect_set_loop_controls_directly and
vect_update_ivs_after_vectorizer_for_early_breaks to use
standard_iv_increment_position.
This moves the IV increment to the end of the loop which allows these
loops to later have loop variant increments.
gcc/ChangeLog:
* tree-vect-loop-manip.cc (vect_set_loop_controls_directly):
Use standard_iv_increment_position instead of
vect_iv_increment_position.
(vect_set_loop_condition_partial_vectors_avx512): Likewise
(vect_set_loop_condition_normal): Likewise.
* tree-vect-loop.cc
(vect_update_ivs_after_vectorizer_for_early_breaks):
Likewise.
(already approved
https://gcc.gnu.org/pipermail/gcc-patches/2026-October/733863.html)
---
gcc/tree-vect-loop-manip.cc | 17 +++++++----------
gcc/tree-vect-loop.cc | 3 +--
2 files changed, 8 insertions(+), 12 deletions(-)
diff --git a/gcc/tree-vect-loop-manip.cc b/gcc/tree-vect-loop-manip.cc
index f8e259c19bd..3421159a042 100644
--- a/gcc/tree-vect-loop-manip.cc
+++ b/gcc/tree-vect-loop-manip.cc
@@ -619,8 +619,8 @@ vect_set_loop_controls_directly (class loop *loop,
loop_vec_info loop_vinfo,
tree index_before_incr, index_after_incr;
gimple_stmt_iterator incr_gsi;
bool insert_after;
- edge exit_e = LOOP_VINFO_MAIN_EXIT (loop_vinfo);
- vect_iv_increment_position (exit_e, &incr_gsi, &insert_after);
+ standard_iv_increment_position (loop, &incr_gsi, &insert_after);
+
if (LOOP_VINFO_USING_DECREMENTING_IV_P (loop_vinfo))
{
/* Create an IV that counts down from niters_total and whose step
@@ -690,7 +690,6 @@ vect_set_loop_controls_directly (class loop *loop,
loop_vec_info loop_vinfo,
tree zero_index = build_int_cst (compare_type, 0);
tree test_index, test_limit, first_limit;
- gimple_stmt_iterator *test_gsi;
if (might_wrap_p)
{
/* In principle the loop should stop iterating once the incremented
@@ -729,7 +728,6 @@ vect_set_loop_controls_directly (class loop *loop,
loop_vec_info loop_vinfo,
nitems_total, adjust);
test_limit = gimple_build (preheader_seq, MINUS_EXPR, compare_type,
test_limit, adjust);
- test_gsi = &incr_gsi;
/* Get a safe limit for the first iteration. */
if (nitems_skip)
@@ -760,7 +758,6 @@ vect_set_loop_controls_directly (class loop *loop,
loop_vec_info loop_vinfo,
if (nitems_skip)
test_limit = gimple_build (preheader_seq, PLUS_EXPR, compare_type,
test_limit, nitems_skip);
- test_gsi = &loop_cond_gsi;
first_limit = test_limit;
}
@@ -769,7 +766,7 @@ vect_set_loop_controls_directly (class loop *loop,
loop_vec_info loop_vinfo,
a demotion). */
gimple_seq test_seq = NULL;
test_index = gimple_convert (&test_seq, compare_type, test_index);
- gsi_insert_seq_before (test_gsi, test_seq, GSI_SAME_STMT);
+ gsi_insert_seq_after (&incr_gsi, test_seq, GSI_NEW_STMT);
/* Provide a definition of each control in the group. */
tree next_ctrl = NULL_TREE;
@@ -878,14 +875,14 @@ vect_set_loop_controls_directly (class loop *loop,
loop_vec_info loop_vinfo,
gimple_seq stmts = NULL;
next_ctrl = vect_gen_while (&stmts, ctrl_type, test_index,
this_test_limit, "next_mask");
- gsi_insert_seq_before (test_gsi, stmts, GSI_SAME_STMT);
+ gsi_insert_seq_after (&incr_gsi, stmts, GSI_SAME_STMT);
}
else
{
next_ctrl = make_temp_ssa_name (compare_type, NULL, "next_len");
gimple_seq seq = vect_gen_len (next_ctrl, test_index, this_test_limit,
length_limit);
- gsi_insert_seq_before (test_gsi, seq, GSI_SAME_STMT);
+ gsi_insert_seq_after (&incr_gsi, seq, GSI_SAME_STMT);
}
vect_set_loop_control (loop, ctrl, init_ctrl, next_ctrl);
@@ -1194,7 +1191,7 @@ vect_set_loop_condition_partial_vectors_avx512 (class
loop *loop,
gimple_stmt_iterator incr_gsi;
tree index_before_incr, index_after_incr;
bool insert_after;
- vect_iv_increment_position (exit_edge, &incr_gsi, &insert_after);
+ standard_iv_increment_position (loop, &incr_gsi, &insert_after);
/* The iteration step is the vectorization factor. */
tree iv_step = gimple_convert (&preheader_seq, iv_type,
@@ -1505,7 +1502,7 @@ vect_set_loop_condition_normal (loop_vec_info loop_vinfo,
edge exit_edge,
}
}
- vect_iv_increment_position (exit_edge, &incr_gsi, &insert_after);
+ standard_iv_increment_position (loop, &incr_gsi, &insert_after);
create_iv (init, PLUS_EXPR, step, NULL_TREE, loop,
&incr_gsi, insert_after,
&indx_before_incr, &indx_after_incr,
diff --git a/gcc/tree-vect-loop.cc b/gcc/tree-vect-loop.cc
index 287902089c6..45aacdb2a13 100644
--- a/gcc/tree-vect-loop.cc
+++ b/gcc/tree-vect-loop.cc
@@ -11272,8 +11272,7 @@ vect_update_ivs_after_vectorizer_for_early_breaks
(loop_vec_info loop_vinfo)
/* Write the adjustments at the end of the iv increment. */
bool insert_after;
gimple_stmt_iterator incr_gsi;
- vect_iv_increment_position (LOOP_VINFO_MAIN_EXIT (loop_vinfo), &incr_gsi,
- &insert_after);
+ standard_iv_increment_position (loop, &incr_gsi, &insert_after);
if (insert_after)
gsi_insert_seq_after (&incr_gsi, stmts, GSI_NEW_STMT);
--
2.55.0
