[Bug target/105951] [12/13 Regression] ICE in emit_store_flag, at expmed.cc:6027

[ubizjak at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105951

Uroš Bizjak <ubizjak at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
                 CC|                            |jakub at gcc dot gnu.org
   Last reconfirmed|                            |2022-06-14
             Status|UNCONFIRMED                 |NEW
   Target Milestone|---                         |12.3

--- Comment #1 from Uroš Bizjak <ubizjak at gmail dot com> ---
Confirmed, expand_ifn_atomic_op_fetch_cmp_0 is not prepared for case where
expand_atomic_fetch_op returns NULL_RTX:

  rtx result = expand_atomic_fetch_op (gen_reg_rtx (mode), mem, op,
                                       code, model, true);
  if (lhs)
    {
      result = emit_store_flag_force (target, comp, result, const0_rtx, mode,
                                      0, 1);
      if (result != target)
        emit_move_insn (target, result);
    }

The compilation ICEs when NULL_RTX is passed to emit_store_flag_force.

CC author.