[Bug tree-optimization/96548] New: [11 Regression] ICE in compute_live_loop_exits, at tree-ssa-loop-manip.c:247

[Bug tree-optimization/96548] New: [11 Regression] ICE in compute_live_loop_exits, at tree-ssa-loop-manip.c:247

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96548

            Bug ID: 96548
           Summary: [11 Regression] ICE in compute_live_loop_exits, at
                    tree-ssa-loop-manip.c:247
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: asolokha at gmx dot com
  Target Milestone: ---

gcc-11.0.0-alpha20200809 snapshot (g:71197a5d13d0b540a9b5efe7ae2512d76386e9d1)
ICEs when compiling the following testcase w/ -O1:

int c9, d3;

void
sg (int *rs, int f2)
{
  for (;;)
    {
      if (*rs < 1)
        __builtin_unreachable ();

      for (c9 = 0; c9 < 1; ++c9)
        while (f2 < 1)
          ++c9;

      if (d3)
        c9 += !!f2 ? 0 : d3;
    }
}

% gcc-11.0.0 -O1 -c tr7hy0bz.c
during GIMPLE pass: lim
tr7hy0bz.c: In function 'sg':
tr7hy0bz.c:4:1: internal compiler error: in compute_live_loop_exits, at
tree-ssa-loop-manip.c:247
    4 | sg (int *rs, int f2)
      | ^~
0x6d7a54 compute_live_loop_exits
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200809/work/gcc-11-20200809/gcc/tree-ssa-loop-manip.c:247
0x6d7a54 add_exit_phis_var
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200809/work/gcc-11-20200809/gcc/tree-ssa-loop-manip.c:334
0x6d7a54 add_exit_phis
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200809/work/gcc-11-20200809/gcc/tree-ssa-loop-manip.c:356
0x6d7a54 rewrite_into_loop_closed_ssa_1(bitmap_head*, unsigned int, int, loop*)
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200809/work/gcc-11-20200809/gcc/tree-ssa-loop-manip.c:678
0x6d7a54 rewrite_into_loop_closed_ssa_1(bitmap_head*, unsigned int, int, loop*)
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200809/work/gcc-11-20200809/gcc/tree-ssa-loop-manip.c:631
0xec3e83 tree_ssa_lim
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200809/work/gcc-11-20200809/gcc/tree-ssa-loop-im.c:3126
0xec3e83 execute
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200809/work/gcc-11-20200809/gcc/tree-ssa-loop-im.c:3173

[Bug tree-optimization/96548] [11 Regression] ICE in compute_live_loop_exits, at tree-ssa-loop-manip.c:247 since r11-2574-g6aec53ee4f75a64c

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96548

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2020-08-10
                 CC|                            |marxin at gcc dot gnu.org,
                   |                            |rguenth at gcc dot gnu.org
     Ever confirmed|0                           |1
            Summary|[11 Regression] ICE in      |[11 Regression] ICE in
                   |compute_live_loop_exits, at |compute_live_loop_exits, at
                   |tree-ssa-loop-manip.c:247   |tree-ssa-loop-manip.c:247
                   |                            |since
                   |                            |r11-2574-g6aec53ee4f75a64c

--- Comment #1 from Martin Liška <marxin at gcc dot gnu.org> ---
Started with r11-2574-g6aec53ee4f75a64c.

[Bug tree-optimization/96548] [11 Regression] ICE in compute_live_loop_exits, at tree-ssa-loop-manip.c:247 since r11-2574-g6aec53ee4f75a64c

[dcb314 at hotmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96548

David Binderman <dcb314 at hotmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |dcb314 at hotmail dot com

--- Comment #2 from David Binderman <dcb314 at hotmail dot com> ---
Here is another test case which demonstrates the fault:

int a, b, c, e;
int *d;
void f() {
  if (0) {
    for (; b;) {
      c = f;
    g:
      for (; e;)
        ;
    }
    c |= a ?: 1;
    if (*d)
      d = e;
  }
  goto g;
}

Flag -O2 required.

[Bug tree-optimization/96548] [11 Regression] ICE in compute_live_loop_exits, at tree-ssa-loop-manip.c:247 since r11-2574-g6aec53ee4f75a64c

[cnsun at uwaterloo dot ca]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96548

cnsun at uwaterloo dot ca <cnsun at uwaterloo dot ca> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |cnsun at uwaterloo dot ca

--- Comment #3 from cnsun at uwaterloo dot ca <cnsun at uwaterloo dot ca> ---
Another one.

$ gcc-trunk -v
Using built-in specs.
COLLECT_GCC=gcc-trunk
COLLECT_LTO_WRAPPER=/scratch/software/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/11.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: /tmp/tmp.iVAQqIzIa4-gcc-builder/gcc/configure
--enable-languages=c,c++,lto --prefix=/scratch/software/gcc-trunk
--disable-bootstrap
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 11.0.0 20200818 (experimental) [master revision
:65bdb4763:bb1b7f087bdd028000fd8f84e74b20adccc9d5bb] (GCC) 
$ gcc-trunk -O2 small.c
during GIMPLE pass: lim
small.c: In function ‘main’:
small.c:4:5: internal compiler error: in compute_live_loop_exits, at
tree-ssa-loop-manip.c:247
    4 | int main() {
      |     ^~~~
0x74a390 compute_live_loop_exits
        /tmp/tmp.iVAQqIzIa4-gcc-builder/gcc/gcc/tree-ssa-loop-manip.c:247
0x74a390 add_exit_phis_var
        /tmp/tmp.iVAQqIzIa4-gcc-builder/gcc/gcc/tree-ssa-loop-manip.c:334
0x74a390 add_exit_phis
        /tmp/tmp.iVAQqIzIa4-gcc-builder/gcc/gcc/tree-ssa-loop-manip.c:356
0x74a390 rewrite_into_loop_closed_ssa_1(bitmap_head*, unsigned int, int, loop*)
        /tmp/tmp.iVAQqIzIa4-gcc-builder/gcc/gcc/tree-ssa-loop-manip.c:678
0x74a390 rewrite_into_loop_closed_ssa_1(bitmap_head*, unsigned int, int, loop*)
        /tmp/tmp.iVAQqIzIa4-gcc-builder/gcc/gcc/tree-ssa-loop-manip.c:631
0xfa022b tree_ssa_lim
        /tmp/tmp.iVAQqIzIa4-gcc-builder/gcc/gcc/tree-ssa-loop-im.c:3126
0xfa022b execute
        /tmp/tmp.iVAQqIzIa4-gcc-builder/gcc/gcc/tree-ssa-loop-im.c:3173
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.
$ gcc-trunk -O3 small.c
during GIMPLE pass: lim
small.c: In function ‘main’:
small.c:4:5: internal compiler error: in compute_live_loop_exits, at
tree-ssa-loop-manip.c:247
    4 | int main() {
      |     ^~~~
0x74a390 compute_live_loop_exits
        /tmp/tmp.iVAQqIzIa4-gcc-builder/gcc/gcc/tree-ssa-loop-manip.c:247
0x74a390 add_exit_phis_var
        /tmp/tmp.iVAQqIzIa4-gcc-builder/gcc/gcc/tree-ssa-loop-manip.c:334
0x74a390 add_exit_phis
        /tmp/tmp.iVAQqIzIa4-gcc-builder/gcc/gcc/tree-ssa-loop-manip.c:356
0x74a390 rewrite_into_loop_closed_ssa_1(bitmap_head*, unsigned int, int, loop*)
        /tmp/tmp.iVAQqIzIa4-gcc-builder/gcc/gcc/tree-ssa-loop-manip.c:678
0x74a390 rewrite_into_loop_closed_ssa_1(bitmap_head*, unsigned int, int, loop*)
        /tmp/tmp.iVAQqIzIa4-gcc-builder/gcc/gcc/tree-ssa-loop-manip.c:631
0xfa022b tree_ssa_lim
        /tmp/tmp.iVAQqIzIa4-gcc-builder/gcc/gcc/tree-ssa-loop-im.c:3126
0xfa022b execute
        /tmp/tmp.iVAQqIzIa4-gcc-builder/gcc/gcc/tree-ssa-loop-im.c:3173
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.
$ cat small.c
short a, b, d, f, g, j;
int c, e;
int *h;
int main() {
  int i = 0;
  for (; i < 3; i++)
  l:
    b = j;
  while (d)
    e++;
  g = f ? a : f;
  *h = g;
  if (c)
    goto l;
}

[Bug tree-optimization/96548] [11 Regression] ICE in compute_live_loop_exits, at tree-ssa-loop-manip.c:247 since r11-2574-g6aec53ee4f75a64c

[dcb314 at hotmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96548

--- Comment #4 from David Binderman <dcb314 at hotmail dot com> ---
This bug has been hanging about for over a week now without resolution.

Is the best way to get this into Richard's intray to assign it to him ?

[Bug tree-optimization/96548] [11 Regression] ICE in compute_live_loop_exits, at tree-ssa-loop-manip.c:247 since r11-2574-g6aec53ee4f75a64c

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96548

--- Comment #5 from Martin Liška <marxin at gcc dot gnu.org> ---
Richi is on vacation. I'm pretty sure he'll quick it as soon as he gets back.

[Bug tree-optimization/96548] [11 Regression] ICE in compute_live_loop_exits, at tree-ssa-loop-manip.c:247 since r11-2574-g6aec53ee4f75a64c

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96548

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
             Status|NEW                         |ASSIGNED
   Target Milestone|---                         |11.0

--- Comment #6 from Richard Biener <rguenth at gcc dot gnu.org> ---
Mine.

[Bug tree-optimization/96548] [11 Regression] ICE in compute_live_loop_exits, at tree-ssa-loop-manip.c:247 since r11-2574-g6aec53ee4f75a64c

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96548

--- Comment #7 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:660b5c10dc04988b02a2c3f6baed013340af3ef8

commit r11-2841-g660b5c10dc04988b02a2c3f6baed013340af3ef8
Author: Richard Biener <rguenther@suse.de>
Date:   Tue Aug 25 10:59:24 2020 +0200

    tree-optimization/96548 - fix failure to recompute RPO after CFG change

    This recomputes RPO after store-motion changes the CFG.

    2020-08-25  Richard Biener  <rguenther@suse.de>

            PR tree-optimization/96548
            PR tree-optimization/96760
            * tree-ssa-loop-im.c (tree_ssa_lim): Recompute RPO after
            store-motion.

            * gcc.dg/torture/pr96548.c: New testcase.
            * gcc.dg/torture/pr96760.c: Likewise.

[Bug tree-optimization/96548] [11 Regression] ICE in compute_live_loop_exits, at tree-ssa-loop-manip.c:247 since r11-2574-g6aec53ee4f75a64c

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96548

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

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

--- Comment #8 from Richard Biener <rguenth at gcc dot gnu.org> ---
Fixed.

[Bug tree-optimization/96548] [11 Regression] ICE in compute_live_loop_exits, at tree-ssa-loop-manip.c:247 since r11-2574-g6aec53ee4f75a64c

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96548

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |stefansf at linux dot ibm.com

--- Comment #9 from Richard Biener <rguenth at gcc dot gnu.org> ---
*** Bug 96801 has been marked as a duplicate of this bug. ***