Re: [PATCH] RE: ill effect of <register>+<constant>

["Jan Beulich" <jbeulich at novell dot com>]

>>> Jakub Jelinek <jakub@redhat.com> 25.09.07 18:28 >>>
>On Tue, Sep 25, 2007 at 05:03:12PM +0100, Jan Beulich wrote:
>> >>> "Dave Korn" <dave.korn@artimi.com> 21.09.07 20:12 >>>
>> >On 21 September 2007 18:31, Andreas Schwab wrote:
>> >
>> >> "Dave Korn" <dave.korn@artimi.com> writes:
>> >> 
>> >>>   I don't see how removing an unused and non-useful feature would really
>> >>> count as "crippling".  I'm not suggesting it should be disabled for ppc,
>> >>> but for x86, really .... what could conceivably be the use?
>> >> 
>> >> There are many more architectures besides ppc and x86.  Almost all of
>> >> them have numbered registers.
>> >
>> >  Are you deliberately missing the point on purpose for rhetorical purposes?
>> >I'm not suggesting it makes no sense for any architecture *except* x86.  I
>> >hope that is clearer.  It certainly does make sense for anything with a big
>> >set of idempotent numbered registers.
>> >
>> >  But really, please: what's the use of being able to turn (for example) cx
>> >into edi by adding a number to it?
>> 
>> Here's a patch that disables such for x86 and ia64. Perhaps a few other
>> architecture may want to follow.
>
>Except that x86_64 has numbered registers as well, r8-r15.

But r8+1 doesn't mean r9 in any context. And you could have said the same
for ia64 (with the same reply by me).

Jan