[Bug target/118594] insn does not satisfy its constraints with __bf16 in some cases

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118594

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
The instruction during combine which is causing issues:
```
(insn 47 46 48 2 (set (reg:HI 172)
        (subreg:HI (mem/v/j/c:BF (plus:DI (reg/f:DI 96 virtual-stack-vars)
                    (const_int -257 [0xfffffffffffffeff])) [2 +0 S2 A8]) 0))
"/app/example.cpp":21:17 68 {*movhi_aarch64}
     (expr_list:REG_DEAD (reg/f:DI 96 virtual-stack-vars)
        (nil)))
```