[Bug target/92865] New: [10 Regression] error: unrecognizable insn: in extract_insn, at recog.c:2294 since

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92865

            Bug ID: 92865
           Summary: [10 Regression] error: unrecognizable insn: in
                    extract_insn, at recog.c:2294 since
           Product: gcc
           Version: 10.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: marxin at gcc dot gnu.org
                CC: crazylht at gmail dot com
  Target Milestone: ---

I see the following ICE:

$ cat ice.c
int A[16];

int
main() {
  int i = 0;
  for (; i < 16; i++)
    A[i] = A[i] >= 2;
}

$ gcc -mxop -march=knl -O3 ice.c
ice.c: In function ‘main’:
ice.c:8:1: error: unrecognizable insn:
    8 | }
      | ^
(insn 10 9 11 2 (set (reg:V16SI 91)
        (gt:V16SI (reg:V16SI 90)
            (reg:V16SI 87))) "ice.c":7:10 -1
     (nil))
during RTL pass: vregs
ice.c:8:1: internal compiler error: in extract_insn, at recog.c:2294
0x6b726c _fatal_insn(char const*, rtx_def const*, char const*, int, char
const*)
        /home/marxin/Programming/gcc/gcc/rtl-error.c:108
0x6b7288 _fatal_insn_not_found(rtx_def const*, char const*, int, char const*)
        /home/marxin/Programming/gcc/gcc/rtl-error.c:116
0x6b5497 extract_insn(rtx_insn*)
        /home/marxin/Programming/gcc/gcc/recog.c:2294
0xadcd23 instantiate_virtual_regs_in_insn
        /home/marxin/Programming/gcc/gcc/function.c:1607
0xadcd23 instantiate_virtual_regs
        /home/marxin/Programming/gcc/gcc/function.c:1977
0xadcd23 execute
        /home/marxin/Programming/gcc/gcc/function.c:2026
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.

It's likely caused by r279107