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Re: inline asm and multi-alternative constraints

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.


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