Re: [PATCH 3/6] x86: improve operand reversal

["H.J. Lu" <hjl dot tools at gmail dot com>]

On Thu, Aug 2, 2018 at 5:38 AM, Jan Beulich <JBeulich@suse.com> wrote:
>>>> On 02.08.18 at 14:19, <hjl.tools@gmail.com> wrote:
>> On Wed, Aug 1, 2018 at 11:49 PM, Jan Beulich <JBeulich@suse.com> wrote:
>>> In quite a few cases the .s suffix or {load} / {store} prefixes did not
>>> work as intended, or produced errors when they're supposed to be ignored
>>> when it is not possible to carry out the request.
>>>
>>> The change here re-purposes(?) the .s suffix to no longer mean "store"
>>> (if that's what 's' did stand for), since the forms used in the base
>>> templates are not consistently loads (and we unlikely want to change
>>> that). The pseudo prefixes will now fulfill what their names say, i.e.
>>> {load} now only ever produces a load form encoding (if available) while
>>> {store} only ever produces a store form one (again if available). This
>>> requires minimal test suite adjustments, while the majority of the
>>> changes there are simply additions.
>>>
>>
>> I prefer not to change the behavior of the `.s' suffix, unless it is to fix
>> the wrong encoding.  I don't see the need for the 'swap' pseudo prefix.
>> If the programmer doesn't care load/store encoding, "swap" isn't really
>> useful.
>
> There's no {swap} prefix. I've just (verbally) assigned the meaning of
> "swap" to the .s suffix (which is the behavior it always had afaict,
> rather than forcing a store to be used, as one could have implied from
> it being 's' and it having had the same behavior as {store}, just that
> the behavior was clearly wrong for {store}). This isn't a very good
> association, but I couldn't come up with anything better that would
> fit the 's'.
>
> Please take a look at the testsuite adjustments - this gives a pretty
> good picture, and you'll notice that uses of .s continue to behave as
> before. The adjustments (beyond the various additions) were for
> {load} and/or {store} now behaving according to their names.
>

There are many test changes,  Can you list a couple for before and
after comparison?


-- 
H.J.