[Bug middle-end/112771] New: during GIMPLE pass: bitintlower0 ICE: in build_bitint_type, at tree.cc:7178 with _BitInt(65535) and division by zero

[Bug middle-end/112771] New: during GIMPLE pass: bitintlower0 ICE: in build_bitint_type, at tree.cc:7178 with _BitInt(65535) and division by zero

[zsojka at seznam dot cz]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112771

            Bug ID: 112771
           Summary: during GIMPLE pass: bitintlower0 ICE: in
                    build_bitint_type, at tree.cc:7178 with _BitInt(65535)
                    and division by zero
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: middle-end
          Assignee: unassigned at gcc dot gnu.org
          Reporter: zsojka at seznam dot cz
  Target Milestone: ---
              Host: x86_64-pc-linux-gnu
            Target: x86_64-pc-linux-gnu

Created attachment 56722
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=56722&action=edit
reduced testcase

$ x86_64-pc-linux-gnu-gcc testcase.c 
testcase.c: In function 'foo':
testcase.c:5:5: warning: division by zero [-Wdiv-by-zero]
    5 |   a /= 0;
      |     ^~
during GIMPLE pass: bitintlower0
testcase.c:2:1: internal compiler error: in build_bitint_type, at tree.cc:7178
    2 | foo (void)
      | ^~~
0x891bea build_bitint_type(unsigned long, int)
        /repo/gcc-trunk/gcc/tree.cc:7178
0x2538b8e handle_operand_addr
        /repo/gcc-trunk/gcc/gimple-lower-bitint.cc:2185
0x2539407 lower_muldiv_stmt
        /repo/gcc-trunk/gcc/gimple-lower-bitint.cc:3339
0x254ca76 gimple_lower_bitint
        /repo/gcc-trunk/gcc/gimple-lower-bitint.cc:6349
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.

$ x86_64-pc-linux-gnu-gcc -v
Using built-in specs.
COLLECT_GCC=/repo/gcc-trunk/binary-latest-amd64/bin/x86_64-pc-linux-gnu-gcc
COLLECT_LTO_WRAPPER=/repo/gcc-trunk/binary-trunk-r14-5974-20231129191907-g259bb7a45a2-checking-yes-rtl-df-extra-nobootstrap-amd64/bin/../libexec/gcc/x86_64-pc-linux-gnu/14.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: /repo/gcc-trunk//configure --enable-languages=c,c++
--enable-valgrind-annotations --disable-nls --enable-checking=yes,rtl,df,extra
--disable-bootstrap --with-cloog --with-ppl --with-isl
--build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu
--target=x86_64-pc-linux-gnu --with-ld=/usr/bin/x86_64-pc-linux-gnu-ld
--with-as=/usr/bin/x86_64-pc-linux-gnu-as --disable-libstdcxx-pch
--prefix=/repo/gcc-trunk//binary-trunk-r14-5974-20231129191907-g259bb7a45a2-checking-yes-rtl-df-extra-nobootstrap-amd64
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 14.0.0 20231129 (experimental) (GCC)

[Bug middle-end/112771] during GIMPLE pass: bitintlower0 ICE: in build_bitint_type, at tree.cc:7178 with _BitInt(65535) and division by zero

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112771

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2023-11-30
           Assignee|unassigned at gcc dot gnu.org      |jakub at gcc dot gnu.org

--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 56733
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=56733&action=edit
gcc14-pr112771.patch

Untested fix.  Thanks for the report.

[Bug middle-end/112771] during GIMPLE pass: bitintlower0 ICE: in build_bitint_type, at tree.cc:7178 with _BitInt(65535) and division by zero

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112771

--- Comment #2 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Jakub Jelinek <jakub@gcc.gnu.org>:

https://gcc.gnu.org/g:9bfebcb1b7ae4e7160644f2104424d6bab4a23f7

commit r14-6050-g9bfebcb1b7ae4e7160644f2104424d6bab4a23f7
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Fri Dec 1 10:55:49 2023 +0100

    lower-bitint: Fix up handle_operand_addr for 0 constants [PR112771]

    handle_operand_addr for INTEGER_CSTs uses wi::min_precision (UNSIGNED
    for non-negative constants, SIGNED for negative ones) and from that
    computes mp as minimum number of limbs which can represent that value,
    and in some cases creates a test BITINT_TYPE with that precision to
    categorize it and decide based on that what types to use on the constant
    emitted into memory.  For the actual precisions (what will be passed
    to libgcc) it actually already uses MAX/MIN to adjust the corner cases:
              *prec = MAX (min_prec, 1);
    ...
              *prec = MIN ((int) -min_prec, -2);
    but for integer_zerop min_prec will be 0,
    mp = CEIL (min_prec, limb_prec) * limb_prec;
    will be also 0 and we ICE trying to build unsigned BITINT_TYPE with
    0 precision.

    Fixed thusly by noting even 0 has to be encoded at least as one limb.

    2023-12-01  Jakub Jelinek  <jakub@redhat.com>

            PR middle-end/112771
            * gimple-lower-bitint.cc (bitint_large_huge::handle_operand_addr):
            Use mp = 1 if it is zero.

            * gcc.dg/bitint-44.c: New test.

[Bug middle-end/112771] during GIMPLE pass: bitintlower0 ICE: in build_bitint_type, at tree.cc:7178 with _BitInt(65535) and division by zero

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112771

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

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

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Fixed.