https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115537
Bug ID: 115537
Summary: [15 Regression] vectorizable_reduction ICEs after
g:d66b820f392aa9a7c34d3cddaf3d7c73bf23f82d
Product: gcc
Version: 15.0
Status: UNCONFIRMED
Keywords: ice-on-valid-code
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: tnfchris at gcc dot gnu.org
CC: rguenth at gcc dot gnu.org
Target Milestone: ---
testcase:
---
char *a;
int b;
void c() {
int d = 0, e = 0, f;
for (; f; ++f)
if (a[f] == 5)
;
else if (a[f])
e = 1;
else
d = 1;
if (d)
if (e)
b = 0;
}
---
compiled with -mcpu=neoverse-v1 -O3 produces the following ICE:
during GIMPLE pass: vect
pngrtran.i: In function 'c':
pngrtran.i:3:6: internal compiler error: in vectorizable_reduction, at
tree-vect-loop.cc:8335
3 | void c() {
| ^
0xff74ff vectorizable_reduction(_loop_vec_info*, _stmt_vec_info*, _slp_tree*,
_slp_instance*, vec<stmt_info_for_cost, va_heap, vl_ptr>*)
/opt/buildAgent/work/5c94c4ced6ebfcd0/gcc/tree-vect-loop.cc:8335
0x1b598f7 vect_analyze_stmt(vec_info*, _stmt_vec_info*, bool*, _slp_tree*,
_slp_instance*, vec<stmt_info_for_cost, va_heap, vl_ptr>*)
/opt/buildAgent/work/5c94c4ced6ebfcd0/gcc/tree-vect-stmts.cc:13353
0x10225df vect_slp_analyze_node_operations_1
/opt/buildAgent/work/5c94c4ced6ebfcd0/gcc/tree-vect-slp.cc:6457
0x10225df vect_slp_analyze_node_operations
/opt/buildAgent/work/5c94c4ced6ebfcd0/gcc/tree-vect-slp.cc:6656
0x102253f vect_slp_analyze_node_operations
/opt/buildAgent/work/5c94c4ced6ebfcd0/gcc/tree-vect-slp.cc:6635
0x1023ec3 vect_slp_analyze_operations(vec_info*)
/opt/buildAgent/work/5c94c4ced6ebfcd0/gcc/tree-vect-slp.cc:7053
0xff816f vect_analyze_loop_2
/opt/buildAgent/work/5c94c4ced6ebfcd0/gcc/tree-vect-loop.cc:2953
0xff9fb7 vect_analyze_loop_1
/opt/buildAgent/work/5c94c4ced6ebfcd0/gcc/tree-vect-loop.cc:3484
0xffa6f7 vect_analyze_loop(loop*, vec_info_shared*)
/opt/buildAgent/work/5c94c4ced6ebfcd0/gcc/tree-vect-loop.cc:3642
0x1035547 try_vectorize_loop_1
/opt/buildAgent/work/5c94c4ced6ebfcd0/gcc/tree-vectorizer.cc:1067
0x1035547 try_vectorize_loop
/opt/buildAgent/work/5c94c4ced6ebfcd0/gcc/tree-vectorizer.cc:1183
0x1035a5b execute
/opt/buildAgent/work/5c94c4ced6ebfcd0/gcc/tree-vectorizer.cc:1299
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
after:
commit d66b820f392aa9a7c34d3cddaf3d7c73bf23f82d
Author: Richard Biener <rguent...@suse.de>
Date: Thu Jun 13 14:42:25 2024 +0200
Support single def-use cycle optimization for SLP reduction vectorization
We can at least mimic single def-use cycle optimization when doing
single-lane SLP reductions and that's required to avoid regressing
compared to non-SLP.
* tree-vect-loop.cc (vectorizable_reduction): Allow
single-def-use cycles with SLP.
(vect_transform_reduction): Handle SLP single def-use cycles.
(vect_transform_cycle_phi): Likewise.
* gcc.dg/vect/slp-reduc-12.c: New testcase.
gcc/testsuite/gcc.dg/vect/slp-reduc-12.c | 18 +++++++++++++
gcc/tree-vect-loop.cc | 45 +++++++++++++++++++-------------
2 files changed, 45 insertions(+), 18 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/vect/slp-reduc-12.c
bisect run success
looks like it's hitting the assert:
gcc_assert (op.code != COND_EXPR);
