Re: [PATCH 3/3] x86: ignore high register select bit(s) in 32- and 16-bit modes

["Jan Beulich" <JBeulich at suse dot com>]

>>> On 14.11.17 at 13:43, <hjl.tools@gmail.com> wrote:
> On Mon, Nov 13, 2017 at 11:32 PM, Jan Beulich <JBeulich@suse.com> wrote:
>> +[      ]*[a-f0-9]+:    62 f2 7d 0f 90 0c 00    vpgatherdd \(%eax,%xmm0(,1)?\),%xmm1\{%k7\}
>> +[      ]*[a-f0-9]+:    62 d2 7d 0f 90 0c 00    vpgatherdd \(%eax,%xmm0(,1)?\),%xmm1\{%k7\}
>> +[      ]*[a-f0-9]+:    62 f2 7d 07 90 0c 00    vpgatherdd \(%eax,%xmm0(,1)?\),%xmm1\{%k7\}

I assume this is what ...

> Where are there "(,1)?"?  Under what conditions will
> assembler/disassembler generate
> different outputs?

... you refer to here? I've added those because for the purpose of
the test it is not relevant whether the disassembler produces them,
just like I like to do in other cases where parts of the expected output
are optional to be present. I consider it bad practice not to do so,
and I've been bitten more than once by others not being careful to
permit such optional pieces (or often the other way around - marking
them as required when really they are optional, and once one goes
and cleans up after others, one then also has to touch all these badly
written test cases). Granted I could have gone _farther_ with this,
by e.g. also permitting blanks after the commas (which the
disassembler really should emit for readability).

Jan