[Bug target/104469] New: ICE: in extract_insn, at recog.cc:2769 (unrecognizable insn) with -mavx and __builtin_convertvector()

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104469

            Bug ID: 104469
           Summary: ICE: in extract_insn, at recog.cc:2769 (unrecognizable
                    insn) with -mavx and __builtin_convertvector()
           Product: gcc
           Version: 12.0
            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 52394
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=52394&action=edit
reduced testcase

Compiler output:
$ x86_64-pc-linux-gnu-gcc -mavx testcase.c
testcase.c: In function 'foo':
testcase.c:6:1: warning: AVX512F vector return without AVX512F enabled changes
the ABI [-Wpsabi]
    6 | {
      | ^
testcase.c:8:1: error: unrecognizable insn:
    8 | }
      | ^
(insn 8 7 9 2 (set (reg:V4SI 84)
        (vec_select:V4SI (mem/c:V8SI (plus:DI (reg/f:DI 77 virtual-stack-vars)
                    (const_int -128 [0xffffffffffffff80])) [3 v+0 S32 A256])
            (parallel [
                    (const_int 4 [0x4])
                    (const_int 5 [0x5])
                    (const_int 6 [0x6])
                    (const_int 7 [0x7])
                ]))) "testcase.c":7:10 -1
     (nil))
during RTL pass: vregs
testcase.c:8:1: internal compiler error: in extract_insn, at recog.cc:2769
0x769df8 _fatal_insn(char const*, rtx_def const*, char const*, int, char
const*)
        /repo/gcc-trunk/gcc/rtl-error.cc:108
0x769e7b _fatal_insn_not_found(rtx_def const*, char const*, int, char const*)
        /repo/gcc-trunk/gcc/rtl-error.cc:116
0x75872d extract_insn(rtx_insn*)
        /repo/gcc-trunk/gcc/recog.cc:2769
0x100efe2 instantiate_virtual_regs_in_insn
        /repo/gcc-trunk/gcc/function.cc:1611
0x100efe2 instantiate_virtual_regs
        /repo/gcc-trunk/gcc/function.cc:1985
0x100efe2 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-amd64/bin/x86_64-pc-linux-gnu-gcc
COLLECT_LTO_WRAPPER=/repo/gcc-trunk/binary-trunk-r12-7128-20220209090954-gc6bb1db76b3-checking-yes-rtl-df-extra-nobootstrap-amd64/bin/../libexec/gcc/x86_64-pc-linux-gnu/12.0.1/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-r12-7128-20220209090954-gc6bb1db76b3-checking-yes-rtl-df-extra-nobootstrap-amd64
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 12.0.1 20220209 (experimental) (GCC)