[PATCH v3 4/7] x86-64: further re-work insn/suffix recognition to also cover MOVSL

[Jan Beulich]

On 12.10.2022 19:10, H.J. Lu wrote:
> On Wed, Oct 12, 2022 at 12:08 AM Jan Beulich <jbeulich@suse.com> wrote:
>>
>> On 11.10.2022 19:44, H.J. Lu wrote:
>>> On Wed, Oct 5, 2022 at 12:24 AM Jan Beulich <jbeulich@suse.com> wrote:
>>>>
>>>> PR gas/29524
>>>> In order to make MOVSL{,Q} behave similarly to MOVSB{W,L,Q} and
>>>> MOVSW{L,Q} we need to defer parse_insn()'s emitting of errors unrelated
>>>> to prefix parsing. Utilize i.error just like match_template() does.
>>>
>>> Since movs{b,w,l,q} are string instructions, integer sign extensions
>>> require a suffix to specify the destination size.  This is different from other
>>> integer instructions.  Since only the new assembler allows the implicit suffix,
>>> it won't be easy to use.  We should improve error messages, but allowing
>>> new syntax doesn't help much.
>>
>> It is an earlier change making most of this consistent with MOVZ*; it is
> 
> MOVZ is different.  There are no MOVZ string instructions.  MOVS has
> different meanings in ISA.   MOVS difference from MOVZ in assembly
> syntax should be expected.

You've said so before, yes, but I continue to disagree. And as we can see
from the series things can be made work consistently (and imo nothing else
should have been done right from the beginning).

Jan