[PATCH] x86: allow suffix-less sign-extending movsb, movsw, and movsl

[H.J. Lu]

On Fri, Jul 1, 2016 at 8:19 AM, Jan Beulich <JBeulich@suse.com> wrote:
>>>> On 01.07.16 at 17:12, <hjl.tools@gmail.com> wrote:
>> On Fri, Jul 1, 2016 at 7:55 AM, Jan Beulich <JBeulich@suse.com> wrote:
>>>>>> On 01.07.16 at 16:24, <jonas-devlists@watlock.be> wrote:
>>>> So in the end, I guess the movzb/movzw change is fine, but this one is
>>>> not. It's in inherent inconsistency related to the ability of leaving
>>>> away the size suffixes in combination with the chosen mnemonics, it
>>>> seems.
>>>
>>> I do not understand what inconsistency you refer to here. The
>>> only inconsistency I can see is that one can't omit the suffixes
>>> from these three instructions, unlike any others with GPR
>>> operands.
>>
>> This mnemonic inconsistency comes from ISA and AT&T syntax.
>> But there are no issues now.
>
> There is - as said, I fell into the trap seeing "movzb" in source code
> and assuming I then could also use "movzw" or "movsb" (etc). I
> can certainly open a bug if that helps you re-consider.

It is unfortunate.  But it won't lead to wrong instructions being used.

>>  Why create new ones?
>
> Where are there new issues being created?
>

Possible confusion.


-- 
H.J.