inline asm and multi-alternative constraints

[Jeff Law]

On 11/11/2015 02:19 AM, David Wohlferd wrote:
> On 11/9/2015 1:52 PM, Jeff Law wrote:
>> On 11/07/2015 12:50 AM, David Wohlferd wrote:
>>>
>>> - Starting with 'modifiers', "=+&" and (reluctantly) "%" seem reasonable
>>> for inline asm.  But both "#*" seem sketchy.
>> Right.  =+& are no-brainer yes, as are the constants 0-9.  % is
>> probably OK as well.
>>
>> #* are similar to !? in that they are inherently tied into the
>> register class preferencing implementation and documenting them would
>> be inadvisable.
>
> Actually, #* are already doc'ed in the user guide.  Are you advising
> they be removed?
Yes.  Much like ?! they are pretty tied to implementation details, just 
not so badly :-)

It may seem like they've got clearer semantics, and they did at one 
time, but they don't anymore.


>
> If so, the attached patch does this.  It also removes references to
> define_peephole2 and define_splits from the user guide version of this
> page.  There are other parts of this page that are more md than ug, but
> these are the ones that annoyed me the most.
I'll install momentarily.

jeff