[Bug tree-optimization/106249] New: ICE in check_loop_closed_ssa_def, at tree-ssa-loop-manip.cc:645

[Bug tree-optimization/106249] New: ICE in check_loop_closed_ssa_def, at tree-ssa-loop-manip.cc:645

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106249

            Bug ID: 106249
           Summary: ICE in check_loop_closed_ssa_def, at
                    tree-ssa-loop-manip.cc:645
           Product: gcc
           Version: 13.0
            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: ---

gfortran 13.0.0 20220710 snapshot (g:0587cef3d7962a8b0f44779589ba2920dd3d71e5)
ICEs when compiling the following testcase w/ -O1 -fpeel-loops
-funreachable-traps:

      SUBROUTINE YYPARS(LSTACK,YYPS,YYSTAT)
      INTEGER LSTACK,YYPS,YYSTAT
      INTEGER YYXI
      INTEGER YYEXCA(0:11)

      YYXI = 1
 10   CONTINUE

      IF (YYPS .GT. LSTACK) CALL ERRORM()

 30   CONTINUE
      IF ((YYEXCA(YYXI) .NE. (-1)) .OR. (YYEXCA(YYXI) .NE. YYSTAT)) THEN
         YYXI = YYXI + 2
         GO TO 30
      END IF
      GO TO 10

      RETURN

      END

% gfortran-13.0.0 -O1 -fpeel-loops -funreachable-traps -c apyn3fnn.f
during GIMPLE pass: cunroll
apyn3fnn.f:1:23:

    1 |       SUBROUTINE YYPARS(LSTACK,YYPS,YYSTAT)
      |                       ^
internal compiler error: in check_loop_closed_ssa_def, at
tree-ssa-loop-manip.cc:645
0x771827 check_loop_closed_ssa_def
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220710/work/gcc-13-20220710/gcc/tree-ssa-loop-manip.cc:645
0x10e97c4 check_loop_closed_ssa_bb
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220710/work/gcc-13-20220710/gcc/tree-ssa-loop-manip.cc:659
0x10eab26 verify_loop_closed_ssa(bool, loop*)
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220710/work/gcc-13-20220710/gcc/tree-ssa-loop-manip.cc:695
0x10eab26 verify_loop_closed_ssa(bool, loop*)
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220710/work/gcc-13-20220710/gcc/tree-ssa-loop-manip.cc:679
0x10d24d6 tree_unroll_loops_completely
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220710/work/gcc-13-20220710/gcc/tree-ssa-loop-ivcanon.cc:1499
0x10d2551 execute
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220710/work/gcc-13-20220710/gcc/tree-ssa-loop-ivcanon.cc:1603
0x10d2551 execute
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220710/work/gcc-13-20220710/gcc/tree-ssa-loop-ivcanon.cc:1593

[Bug tree-optimization/106249] [13 Regression] ICE in check_loop_closed_ssa_def, at tree-ssa-loop-manip.cc:645

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106249

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |13.0
            Summary|ICE in                      |[13 Regression] ICE in
                   |check_loop_closed_ssa_def,  |check_loop_closed_ssa_def,
                   |at                          |at
                   |tree-ssa-loop-manip.cc:645  |tree-ssa-loop-manip.cc:645

[Bug tree-optimization/106249] [13 Regression] ICE in check_loop_closed_ssa_def, at tree-ssa-loop-manip.cc:645

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106249

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
                 CC|                            |jakub at gcc dot gnu.org,
                   |                            |jason at gcc dot gnu.org,
                   |                            |rguenth at gcc dot gnu.org
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2022-07-11

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
Confirmed.  The issue is that __builtin_unreachable () is 'const' while
__builtin_trap () is neither 'const' nor 'pure'.  Passes inserting
__builtin_unreachable () rightfully expect 'unreachable' semantics.

IMHO changing __builtin_unreachable to __builtin_trap under-the-hood was a
very wrong thing to do.

Can we reconsider that please?

[Bug tree-optimization/106249] [13 Regression] ICE in check_loop_closed_ssa_def, at tree-ssa-loop-manip.cc:645

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106249

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
DEF_GCC_BUILTIN        (BUILT_IN_TRAP, "trap", BT_FN_VOID,
ATTR_NORETURN_NOTHROW_LEAF_COLD_LIST)
DEF_GCC_BUILTIN        (BUILT_IN_UNREACHABLE, "unreachable", BT_FN_VOID,
ATTR_CONST_NORETURN_NOTHROW_LEAF_COLD_LIST)

[Bug tree-optimization/106249] [13 Regression] ICE in check_loop_closed_ssa_def, at tree-ssa-loop-manip.cc:645

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106249

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
Maybe just make frontend / user inserted __builtin_unreachable ()s trap but not
middle-end inserted ones which are generally only to aid DCE?  Thus, rewrite
them at gimplification time instead of hacking the delcs to be the same?

[Bug tree-optimization/106249] [13 Regression] ICE in check_loop_closed_ssa_def, at tree-ssa-loop-manip.cc:645

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106249

--- Comment #4 from Arseny Solokha <asolokha at gmx dot com> ---
Finally, a C testcase, and w/o -funreachable-traps:

void
foo (double *arr)
{
  int i, j;

  for (i = 0; i < 4; ++i)
    for (j = 0; j < 4; ++j)
      arr[j] = 0;

  for (i = 1; i < 4; ++i)
    for (j = 0; j < 4; ++j)
      arr[j] = 1.0 / (i + 1);
}

% gcc-13.0.0 -O1 -floop-unroll-and-jam --param unroll-jam-min-percent=0 -c
o87rfyb9.c
during GIMPLE pass: unrolljam
o87rfyb9.c: In function 'foo':
o87rfyb9.c:2:1: internal compiler error: in check_loop_closed_ssa_def, at
tree-ssa-loop-manip.cc:645
    2 | foo (double *arr)
      | ^~~
0x772a0b check_loop_closed_ssa_def
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220710/work/gcc-13-20220710/gcc/tree-ssa-loop-manip.cc:645
0x1064e6f check_loop_closed_ssa_bb
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220710/work/gcc-13-20220710/gcc/tree-ssa-loop-manip.cc:670
0x1066116 verify_loop_closed_ssa(bool, loop*)
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220710/work/gcc-13-20220710/gcc/tree-ssa-loop-manip.cc:695
0x1066116 verify_loop_closed_ssa(bool, loop*)
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220710/work/gcc-13-20220710/gcc/tree-ssa-loop-manip.cc:679
0x1068849 checking_verify_loop_closed_ssa
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220710/work/gcc-13-20220710/gcc/tree-ssa-loop-manip.h:34
0x1068849 tree_transform_and_unroll_loop(loop*, unsigned int, tree_niter_desc*,
void (*)(loop*, void*), void*)
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220710/work/gcc-13-20220710/gcc/tree-ssa-loop-manip.cc:1431
0x1cf56cc tree_loop_unroll_and_jam
       
/var/tmp/portage/sys-devel/gcc-13.0.0_p20220710/work/gcc-13-20220710/gcc/gimple-loop-jam.cc:595

[Bug tree-optimization/106249] [13 Regression] ICE in check_loop_closed_ssa_def, at tree-ssa-loop-manip.cc:645 since r13-1450-gd2a898666609452e

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106249

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[13 Regression] ICE in      |[13 Regression] ICE in
                   |check_loop_closed_ssa_def,  |check_loop_closed_ssa_def,
                   |at                          |at
                   |tree-ssa-loop-manip.cc:645  |tree-ssa-loop-manip.cc:645
                   |                            |since
                   |                            |r13-1450-gd2a898666609452e

--- Comment #5 from Martin Liška <marxin at gcc dot gnu.org> ---
Started with r13-1450-gd2a898666609452e.

[Bug tree-optimization/106249] [13 Regression] ICE in check_loop_closed_ssa_def, at tree-ssa-loop-manip.cc:645 since r13-1450-gd2a898666609452e

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106249

--- Comment #6 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:c479c40f8c8fee0fb70e8a365b61c55739f448e1

commit r13-1653-gc479c40f8c8fee0fb70e8a365b61c55739f448e1
Author: Richard Biener <rguenther@suse.de>
Date:   Wed Jul 13 08:27:57 2022 +0200

    tree-optimization/106249 - unroll-and-jam and LC SSA upate

    When I delayed the LC SSA update in unroll-and-jam this exposed
    an issue that tree_transform_and_unroll_loop does a full function
    LC SSA verification when new_loop is NULL (when it doesn't need to
    do versioning).  That wasn't intended.  I also took the chance
    to make the versioning in tree_transform_and_unroll_loop use
    TODO_update_ssa_nophi for the loop versioning SSA update which
    I somehow missed earlier.

            PR tree-optimization/106249
            * tree-ssa-loop-manip.cc (tree_transform_and_unroll_loop):
            Only verify LC SSA of the new_loop if we created it.
            Use TODO_update_ssa_nophi for the SSA update after versioning
            the loop.

            * gcc.dg/pr106249.c: New testcase.

[Bug tree-optimization/106249] [13 Regression] ICE in check_loop_closed_ssa_def, at tree-ssa-loop-manip.cc:645 since r13-1450-gd2a898666609452e

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106249

--- Comment #7 from Richard Biener <rguenth at gcc dot gnu.org> ---
The testcase from comment#4 is now fixed, the original issue with
-funreachable-traps is still present.

[Bug tree-optimization/106249] [13 Regression] ICE in check_loop_closed_ssa_def, at tree-ssa-loop-manip.cc:645 since r13-1450-gd2a898666609452e

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106249

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |zhendong.su at inf dot ethz.ch

--- Comment #8 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
*** Bug 106306 has been marked as a duplicate of this bug. ***

[Bug tree-optimization/106249] [13 Regression] ICE in check_loop_closed_ssa_def, at tree-ssa-loop-manip.cc:645 since r13-1450-gd2a898666609452e

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106249

--- Comment #9 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Related to PR106099

[Bug tree-optimization/106249] [13 Regression] ICE in check_loop_closed_ssa_def, at tree-ssa-loop-manip.cc:645 since r13-1450-gd2a898666609452e

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106249

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

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

--- Comment #10 from Richard Biener <rguenth at gcc dot gnu.org> ---
No longer ICEs for me, so fixed.

[Bug tree-optimization/106249] [13 Regression] ICE in check_loop_closed_ssa_def, at tree-ssa-loop-manip.cc:645 since r13-1450-gd2a898666609452e

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106249

Arseny Solokha <asolokha at gmx dot com> changed:

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

--- Comment #11 from Arseny Solokha <asolokha at gmx dot com> ---
Actually, testcase from comment 0 still ICEs for me, as well as its slightly
modified version:

subroutine foo()
  implicit none
  integer :: x
  integer :: a(0:1)

10 x = x + 1
20 if ((a(x) .ne. (-1)) .or. (a(x + 1) .ne. (-1))) then
     x = x + 1
     go to 20
  end if

  call undefined()
  go to 10

  return

end subroutine foo

% gfortran-13 -O1 -fpeel-loops -funreachable-traps -c comment0.f
during GIMPLE pass: cunroll
comment0.f:1:23:

    1 |       SUBROUTINE YYPARS(LSTACK,YYPS,YYSTAT)
      |                       ^
internal compiler error: in check_loop_closed_ssa_def, at
tree-ssa-loop-manip.cc:645
0x7804b7 check_loop_closed_ssa_def
       
/var/tmp/portage/sys-devel/gcc-13.0.1_p20230205/work/gcc-13-20230205/gcc/tree-ssa-loop-manip.cc:645
0x10fc384 check_loop_closed_ssa_bb
       
/var/tmp/portage/sys-devel/gcc-13.0.1_p20230205/work/gcc-13-20230205/gcc/tree-ssa-loop-manip.cc:659
0x10fd746 verify_loop_closed_ssa(bool, loop*)
       
/var/tmp/portage/sys-devel/gcc-13.0.1_p20230205/work/gcc-13-20230205/gcc/tree-ssa-loop-manip.cc:695
0x10fd746 verify_loop_closed_ssa(bool, loop*)
       
/var/tmp/portage/sys-devel/gcc-13.0.1_p20230205/work/gcc-13-20230205/gcc/tree-ssa-loop-manip.cc:679
0x10e5461 tree_unroll_loops_completely
       
/var/tmp/portage/sys-devel/gcc-13.0.1_p20230205/work/gcc-13-20230205/gcc/tree-ssa-loop-ivcanon.cc:1499
0x10e54d1 execute
       
/var/tmp/portage/sys-devel/gcc-13.0.1_p20230205/work/gcc-13-20230205/gcc/tree-ssa-loop-ivcanon.cc:1603
0x10e54d1 execute
       
/var/tmp/portage/sys-devel/gcc-13.0.1_p20230205/work/gcc-13-20230205/gcc/tree-ssa-loop-ivcanon.cc:1593

% gfortran-13 -O1 -fpeel-loops -funreachable-traps -c comment11.f90
during GIMPLE pass: cunroll
comment11.f90:1:14:

    1 | subroutine foo()
      |              ^
internal compiler error: in check_loop_closed_ssa_def, at
tree-ssa-loop-manip.cc:645
<identical backtrace follows>

% gfortran-13 -v
Using built-in specs.
COLLECT_GCC=gfortran-13
COLLECT_LTO_WRAPPER=/usr/libexec/gcc/x86_64-pc-linux-gnu/13/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with:
/var/tmp/portage/sys-devel/gcc-13.0.1_p20230205/work/gcc-13-20230205/configure
--host=x86_64-pc-linux-gnu --build=x86_64-pc-linux-gnu --prefix=/usr
--bindir=/usr/x86_64-pc-linux-gnu/gcc-bin/13
--includedir=/usr/lib/gcc/x86_64-pc-linux-gnu/13/include
--datadir=/usr/share/gcc-data/x86_64-pc-linux-gnu/13
--mandir=/usr/share/gcc-data/x86_64-pc-linux-gnu/13/man
--infodir=/usr/share/gcc-data/x86_64-pc-linux-gnu/13/info
--with-gxx-include-dir=/usr/lib/gcc/x86_64-pc-linux-gnu/13/include/g++-v13
--with-python-dir=/share/gcc-data/x86_64-pc-linux-gnu/13/python
--enable-languages=c,c++,fortran --enable-obsolete --enable-secureplt
--disable-werror --with-system-zlib --disable-nls
--disable-libunwind-exceptions --enable-checking=yes
--with-gcc-major-version-only --enable-esp --enable-libstdcxx-time
--disable-libstdcxx-pch --enable-shared --enable-threads=posix
--enable-__cxa_atexit --enable-clocale=gnu --disable-multilib
--with-multilib-list=m64 --disable-fixed-point --enable-targets=all
--enable-libgomp --disable-libssp --disable-libada --disable-cet
--disable-systemtap --enable-valgrind-annotations --disable-vtable-verify
--disable-libvtv --without-zstd --enable-lto --with-isl
--disable-isl-version-check --enable-default-ssp
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 13.0.1 20230205 (experimental) (GCC)

[Bug tree-optimization/106249] [13 Regression] ICE in check_loop_closed_ssa_def, at tree-ssa-loop-manip.cc:645 since r13-1450-gd2a898666609452e

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106249

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

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

--- Comment #12 from Richard Biener <rguenth at gcc dot gnu.org> ---
This new testcase no longer ICEs for me on trunk.