[Bug tree-optimization/110116] New: ICE on valid code at -O3 on x86_64-linux-gnu: verify_gimple failed

[Bug tree-optimization/110116] New: ICE on valid code at -O3 on x86_64-linux-gnu: verify_gimple failed

[zhendong.su at inf dot ethz.ch]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110116

            Bug ID: 110116
           Summary: ICE on valid code at -O3 on x86_64-linux-gnu:
                    verify_gimple failed
           Product: gcc
           Version: unknown
            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: ---

It appears to be a recent regression.

Compiler Explorer: https://godbolt.org/z/MTsfTocn7

[635] % gcctk -v
Using built-in specs.
COLLECT_GCC=gcctk
COLLECT_LTO_WRAPPER=/local/home/suz/suz-local/software/local/gcc-trunk/bin/../libexec/gcc/x86_64-pc-linux-gnu/14.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../gcc-trunk/configure --disable-bootstrap
--enable-checking=yes --prefix=/local/suz-local/software/local/gcc-trunk
--enable-sanitizers --enable-languages=c,c++ --disable-werror
--disable-multilib
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 14.0.0 20230604 (experimental) [master r14-924-gd709841ae0f] (GCC)
[636] %
[636] % gcctk -O3 small.c
small.c: In function ‘main’:
small.c:6:21: warning: iteration 2147483646 invokes undefined behavior
[-Waggressive-loop-optimizations]
    6 |     for (b = 1; b; b++)
      |                    ~^~
small.c:6:17: note: within this loop
    6 |     for (b = 1; b; b++)
      |                 ^
small.c:4:5: error: type mismatch in binary expression
    4 | int main() {
      |     ^~~~
vector(4) char

vector(4) char

vector(4) unsigned char

_73 = vect__48.34_68 & vect__6.22_19;
during GIMPLE pass: reassoc
small.c:4:5: internal compiler error: verify_gimple failed
0x100327e verify_gimple_in_cfg(function*, bool, bool)
        ../../gcc-trunk/gcc/tree-cfg.cc:5652
0xe98674 execute_function_todo
        ../../gcc-trunk/gcc/passes.cc:2098
0xe98bcb execute_todo
        ../../gcc-trunk/gcc/passes.cc:2152
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.
[637] %
[637] % cat small.c
unsigned char a[5];
int b, d;
char c;
int main() {
  if (d) {
    for (b = 1; b; b++)
      c &= d = 1;
    for (; d < 5; d++)
      c &= a[d];
  }
  return 0;
}

[Bug tree-optimization/110116] [12/13/14 Regression] ICE on valid code at -O3 on x86_64-linux-gnu: verify_gimple failed

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110116

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|ICE on valid code at -O3 on |[12/13/14 Regression] ICE
                   |x86_64-linux-gnu:           |on valid code at -O3 on
                   |verify_gimple failed        |x86_64-linux-gnu:
                   |                            |verify_gimple failed
   Last reconfirmed|                            |2023-06-04
           Keywords|                            |ice-checking,
                   |                            |ice-on-valid-code,
                   |                            |needs-bisection
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1
   Target Milestone|---                         |12.4
      Known to fail|                            |12.1.0, 12.2.0, 12.3.0,
                   |                            |13.1.0

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
> It appears to be a recent regression.

It is not. `-O3 -fchecking=2` ICEs all the way back to GCC 12.1.0

Confirmed.

[Bug tree-optimization/110116] [12/13/14 Regression] ICE on valid code at -O3 on x86_64-linux-gnu: verify_gimple failed

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110116

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Version|unknown                     |13.1.1
           Priority|P3                          |P2

[Bug tree-optimization/110116] [12/13/14 Regression] ICE on valid code at -O3 on x86_64-linux-gnu: verify_gimple failed

[tkoenig at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110116

--- Comment #2 from Thomas Koenig <tkoenig at gcc dot gnu.org> ---
Looks like this has been fixed in the meantime:

tkoenig@gcc188:~> gcc -O3 small.c 
small.c: In function 'main':
small.c:6:21: warning: iteration 2147483646 invokes undefined behavior
[-Waggressive-loop-optimizations]
    6 |     for (b = 1; b; b++)
      |                    ~^~
small.c:6:17: note: within this loop
    6 |     for (b = 1; b; b++)
      |                 ^
tkoenig@gcc188:~> gcc --version
gcc (GCC) 14.0.0 20231101 (experimental) [master r13-4915-g9b111debbfb]
Copyright (C) 2023 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

tkoenig@gcc188:~> cat small.c 
unsigned char a[5];
int b, d;
char c;
int main() {
  if (d) {
    for (b = 1; b; b++)
      c &= d = 1;
    for (; d < 5; d++)
      c &= a[d];
  }
  return 0;
}

Still interesting which revision fixed it.

[Bug tree-optimization/110116] [12/13 Regression] ICE on valid code at -O3 on x86_64-linux-gnu: verify_gimple failed

[tkoenig at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110116

Thomas Koenig <tkoenig at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[12/13/14 Regression] ICE   |[12/13 Regression] ICE on
                   |on valid code at -O3 on     |valid code at -O3 on
                   |x86_64-linux-gnu:           |x86_64-linux-gnu:
                   |verify_gimple failed        |verify_gimple failed
           See Also|                            |https://gcc.gnu.org/bugzill
                   |                            |a/show_bug.cgi?id=111614
      Known to work|                            |14.0

--- Comment #3 from Thomas Koenig <tkoenig at gcc dot gnu.org> ---
r14-4303-g88d79b9b03eccf fixed it:

88d79b9b03eccf39921d13c2cbd1acc50aeda126 is the first fixed commit
commit 88d79b9b03eccf39921d13c2cbd1acc50aeda126
Author: Richard Biener <rguenther@suse.de>
Date:   Thu Sep 28 09:41:30 2023 +0200

    tree-optimization/111614 - missing convert in
undistribute_bitref_for_vector

    The following adjusts a flawed guard for converting the first vector
    of the sum we create in undistribute_bitref_for_vector.

            PR tree-optimization/111614
            * tree-ssa-reassoc.cc (undistribute_bitref_for_vector): Properly
            convert the first vector when required.

            * gcc.dg/torture/pr111614.c: New testcase.

 gcc/testsuite/gcc.dg/torture/pr111614.c | 23 +++++++++++++++++++++++
 gcc/tree-ssa-reassoc.cc                 | 27 +++++++++++++++------------
 2 files changed, 38 insertions(+), 12 deletions(-)
 create mode 100644 gcc/testsuite/gcc.dg/torture/pr111614.c

Maybe a candidate for backporting?  Unlike PR111614, this does not appear
to be latent.

[Bug tree-optimization/110116] [12/13 Regression] ICE on valid code at -O3 on x86_64-linux-gnu: verify_gimple failed

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110116
Bug 110116 depends on bug 111614, which changed state.

Bug 111614 Summary: [11 Regression] ICE at -O2: verify_gimple failed since r14-2282-gf703d2fd3f0
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111614

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

[Bug tree-optimization/110116] [12/13 Regression] ICE on valid code at -O3 on x86_64-linux-gnu: verify_gimple failed

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110116

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to fail|                            |13.2.0
             Status|NEW                         |RESOLVED
      Known to work|                            |12.3.1, 13.2.1
         Resolution|---                         |FIXED

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