Re: e500 core lacks lswi, lswx, stswi, and stswx instructions.

> On Jan 20, 2015, at 10:10 AM, matthew green <[email protected]> wrote:
> 
> 
> Matt Thomas writes:
>> 
>>> On Jan 20, 2015, at 9:26 AM, matthew green <[email protected]> wrote:
>>>> I fixed rs6000.c to not enable string instructions for NetBSD with -Os.
>>> 
>>> doesn't that bloat code for all the other non e500 ppc users of -Os?
>> 
>> So?  We already use a common subset of powerpc instructions for all
>> platforms.
>> Otherwise we wouldn't -mstrict-align since most OEA/BookE don't require
>> it.
>> 
>> Not using the string instructions is not a big deal.
> 
> i don't agree.
> 
> -Os i asking to make small binaries.  you're now avoiding them
> in all cases when a large portion of users don't need this and
> it bloats the binary and slows the run time.

Actually string instructions are not faster, just smaller. :)
Anyways, calls to the str*/mem* routines will be about the same
size if not smaller.  Not using -mstrict-align would result in
smaller executables too but we don't do that either.

> why isn't this being part of e500 or whatever default enough?

Ask Freescale. :)

> why do we have to penalise everyone else?

This is too have a common userland that works on all powerpcs.
The penalty is minimal.