[Bug tree-optimization/97838] New: ICE at -O3 on x86_64-pc-linux-gnu: Segmentation fault

[Bug tree-optimization/97838] New: ICE at -O3 on x86_64-pc-linux-gnu: Segmentation fault

[zhendong.su at inf dot ethz.ch]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97838

            Bug ID: 97838
           Summary: ICE at -O3 on x86_64-pc-linux-gnu: Segmentation fault
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: zhendong.su at inf dot ethz.ch
  Target Milestone: ---

[530] % gcctk -v
Using built-in specs.
COLLECT_GCC=gcctk
COLLECT_LTO_WRAPPER=/local/suz-local/software/local/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/11.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../gcc-trunk/configure --disable-bootstrap
--prefix=/local/suz-local/software/local/gcc-trunk --enable-languages=c,c++
--disable-werror --enable-multilib --with-system-zlib
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 11.0.0 20201115 (experimental) [master revision
406b452dc0e:d88ff5a679d:faab61b585a8b4a42454f085dd6b7815992a98f5] (GCC)
[531] %
[531] % gcctk -O2 -c small.c
[532] %
[532] % gcctk -O3 -c small.c
during GIMPLE pass: vect
small.c: In function ‘f’:
small.c:3:6: internal compiler error: Segmentation fault
    3 | void f() {
      |      ^
0xd0426f crash_signal
        ../../gcc-trunk/gcc/toplev.c:330
0x1006810 auto_vec<int, 0ul>::auto_vec()
        ../../gcc-trunk/gcc/vec.h:1540
0x1006810 vect_optimize_slp(vec_info*)
        ../../gcc-trunk/gcc/tree-vect-slp.c:2702
0xfea9c7 vect_analyze_loop_2
        ../../gcc-trunk/gcc/tree-vect-loop.c:2300
0xfea9c7 vect_analyze_loop(loop*, vec_info_shared*)
        ../../gcc-trunk/gcc/tree-vect-loop.c:2895
0x1015dbc try_vectorize_loop_1
        ../../gcc-trunk/gcc/tree-vectorizer.c:995
0x1016949 vectorize_loops()
        ../../gcc-trunk/gcc/tree-vectorizer.c:1229
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
[533] %
[533] % cat small.c
int a, b, c, d;

void f() {
  while (c++) {
    int e = -1;
    d = a ? e / a : e;
    b ^= ~d;
  }
}

[Bug tree-optimization/97838] [11 Regression] ICE at -O3 on x86_64-pc-linux-gnu: Segmentation fault by r11-4428

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97838

H.J. Lu <hjl.tools at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|ICE at -O3 on               |[11 Regression] ICE at -O3
                   |x86_64-pc-linux-gnu:        |on x86_64-pc-linux-gnu:
                   |Segmentation fault          |Segmentation fault by
                   |                            |r11-4428
             Status|UNCONFIRMED                 |NEW
   Target Milestone|---                         |11.0
   Last reconfirmed|                            |2020-11-15
                 CC|                            |hjl.tools at gmail dot com,
                   |                            |rguenther at suse dot de
     Ever confirmed|0                           |1

--- Comment #1 from H.J. Lu <hjl.tools at gmail dot com> ---
It is caused by r11-4428

[Bug tree-optimization/97838] [11 Regression] ICE at -O3 on x86_64-pc-linux-gnu: Segmentation fault by r11-4428

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97838

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Assignee|unassigned at gcc dot gnu.org      |rguenth at gcc dot gnu.org
           Priority|P3                          |P1
             Status|NEW                         |ASSIGNED

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
Mine.

[Bug tree-optimization/97838] [11 Regression] ICE at -O3 on x86_64-pc-linux-gnu: Segmentation fault by r11-4428

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97838

--- Comment #3 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Richard Biener <rguenth@gcc.gnu.org>:

https://gcc.gnu.org/g:d0a206abc6cbf0e992bf82bbb3584686eae05d34

commit r11-5050-gd0a206abc6cbf0e992bf82bbb3584686eae05d34
Author: Richard Biener <rguenther@suse.de>
Date:   Mon Nov 16 09:28:03 2020 +0100

    tree-optimization/97838 - fix SLP leaf detection

    This properly handles reduction PHI nodes with unrepresented
    initial value as leaf in the SLP graph.

    2020-11-16  Richard Biener  <rguenther@suse.de>

            PR tree-optimization/97838
            * tree-vect-slp.c (vect_slp_build_vertices): Properly handle
            not backwards reachable cycles.
            (vect_optimize_slp): Check a node is leaf before marking it
            visited.

            * gcc.dg/vect/pr97838.c: New testcase.

[Bug tree-optimization/97838] [11 Regression] ICE at -O3 on x86_64-pc-linux-gnu: Segmentation fault by r11-4428

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97838

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED

--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> ---
Fixed.