[PATCH] rs6000: Improve rtx_costs for EQ a bit (PR30967)

[David Edelsohn]

On Wed, May 13, 2015 at 1:29 PM, Segher Boessenkool
<segher@kernel.crashing.org> wrote:
> On Wed, May 13, 2015 at 01:25:16PM -0400, David Edelsohn wrote:
>> >         PR rtl-optimization/30967
>> >         * config/rs6000/rs6000.c (rs6000_rtx_costs): Don't consider
>> >         destination mode for the cost of scc patterns.
>>
>> Okay.
>>
>> Should this be applied to GCC 5 branch?
>
> [ Testing is still in progress. ]
>
> It should be prefectly safe to backport; OTOH, it is just one of very
> many cases where we generate an extra sign-extend, so I don't think it
> is particularly useful.  Your choice :-)

The other prereqs are backported, so probably should backport this also.

Fixing this is a process, not an event.

- David