Re: PPC32 and state of the project

["Kevin.Hendricks" <kevin dot hendricks at sympatico dot ca>]

Hi Franz,

I assume for backward compatibility and since "r2" has its own slot in 
the setjmp buffer
(i.e. JB__GPR2) we do NOT want to change the size OR the layout of the 
jump buffer (see bits/setjmp.h) and we simply just skip reading and 
writing "r2" but only for powerpc32 right?

Thanks,

Kevin



On Monday, January 6, 2003, at 02:23 PM, Franz Sirl wrote:

> On Monday 06 January 2003 16:41, Steve Munroe wrote:
> > Keven Hendricks writes:
> > > Hi Franz,
> > >
> > > > On PPC32 we can simply use R2 as the thread register, it's unused and
> > > > saved/restored by the kernel (in the kernel it's used for the 
> > > > 'current'
> > > > pointer) and doesn't require any changes to the ABI.
> > > Okay R2 it is.  I will start looking at the linuxthreads code mods for
> > > using R2
> > I think there is still one issue to resolve with proposed PPC32 ABI 
> > change.
> > I believe R2 is used for -eabi.
> Besides that -msdata=eabi support is typo-broken in gcc (see the 
> definition of
> SMALL_DATA_REG in rs6000.c), this is no problem on Linux and thus 
> glibc. We
> don't have to care about EABI on Linux. This makes r2 the obvious 
> choice,
> because we still can support -msdata=sysv.
>
> Franz.
----
Kevin B. Hendricks
Associate Professor of Operations and Information Technology
Richard Ivey School of Business, University of Western Ontario
London Ontario, CANADA  N6A 3K7
khendricks@ivey.uwo.ca