[Bug target/107322] New: ICE: in extract_insn, at recog.cc:2791 (unrecognizable insn) with __bf16 compare

["zsojka at seznam dot cz" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107322

            Bug ID: 107322
           Summary: ICE: in extract_insn, at recog.cc:2791 (unrecognizable
                    insn) with __bf16 compare
           Product: gcc
           Version: 13.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: target
          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 53731
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=53731&action=edit
reduced testcase

Compiler output:
$ x86_64-pc-linux-gnu-gcc -fexcess-precision=16 -O testcase.c 
testcase.c: In function 'foo':
testcase.c:8:1: error: unrecognizable insn:
    8 | }
      | ^
(insn 7 6 9 2 (set (reg:CCFP 17 flags)
        (compare:CCFP (reg:BF 88)
            (reg:BF 87))) "testcase.c":7:5 -1
     (nil))
during RTL pass: vregs
testcase.c:8:1: internal compiler error: in extract_insn, at recog.cc:2791
0x78376b _fatal_insn(char const*, rtx_def const*, char const*, int, char
const*)
        /repo/gcc-trunk/gcc/rtl-error.cc:108
0x7837e7 _fatal_insn_not_found(rtx_def const*, char const*, int, char const*)
        /repo/gcc-trunk/gcc/rtl-error.cc:116
0x77239c extract_insn(rtx_insn*)
        /repo/gcc-trunk/gcc/recog.cc:2791
0x1043ee9 instantiate_virtual_regs_in_insn
        /repo/gcc-trunk/gcc/function.cc:1611
0x1043ee9 instantiate_virtual_regs
        /repo/gcc-trunk/gcc/function.cc:1985
0x1043ee9 execute
        /repo/gcc-trunk/gcc/function.cc:2034
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/bin/x86_64-pc-linux-gnu-gcc
COLLECT_LTO_WRAPPER=/repo/gcc-trunk/binary-trunk-r13-3383-20221019140533-g47684e58edc-checking-yes-rtl-df-extra-nobootstrap-amd64/bin/../libexec/gcc/x86_64-pc-linux-gnu/13.0.0/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-r13-3383-20221019140533-g47684e58edc-checking-yes-rtl-df-extra-nobootstrap-amd64
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 13.0.0 20221019 (experimental) (GCC)