[PATCH] x86: don't allow invalid operand combinations for VGATHER

[H.J. Lu]

On Tue, Jul 31, 2012 at 12:49 AM, Jan Beulich <JBeulich@suse.com> wrote:
>>>> On 30.07.12 at 18:10, "H.J. Lu" <hjl.tools@gmail.com> wrote:
>> On Tue, Jul 24, 2012 at 7:18 AM, Jan Beulich <JBeulich@suse.com> wrote:
>>> The VGATHER group of instructions requires that all three involved
>>> xmm/ymm registers are distinct. This patch adds code to check for this,
>>> and at once eliminates a superfluous check for not using PC-relative
>>> addressing for these instructions (the fact that an index register is
>>> required here already excludes valid PC-relative addresses).
>>>
>>
>> The assembler should only check the operands which can't be
>> encoded.  It should shouldn't check if operands are functional
>> correct.  However, I don't mind to issue an error which is controlled
>> by a command line option.
>
> Hmm, not sure. Is there any precedent to such behavior? I as a
> programmer would appreciate if the assembler rejected anything
> that's invalid.
>
> In the case you stay on that position, would making the new
> diagnostic an unconditional warning be acceptable instead?
>

Can you also add a command line option to turn it off and
turn warning into error?

Thanks.

-- 
H.J.