Re: Question on PowerPC setjmp/longjmp ABI

[Troy Benjegerdes <hozer at drgw dot net>]

On Sat, Feb 17, 2001 at 02:55:11PM -0800, Richard Henderson wrote:
> On Sat, Feb 17, 2001 at 12:03:37PM -0800, Geoff Keating wrote:
> > Altivec is a different problem, because Altivec doesn't introduce a
> > new ABI---you can link non-altivec code with altivec code, and this
> > should work just fine.  I think what we'll have to do is increase the
> > size of __jmp_buf, and version everything connected to it.
> 
> I don't think so.  If you want Altivec to not change the ABI,
> then all Altivec registers must be call clobbered, and thus
> they need not be saved in a jmp_buf.

Please correct me if I'm wrong, but then what happens if a process is 
using Altivec and gets a signal? Isn't there a potential for altivec 
registers to get clobbered?

Aside from that, the Altivec Programmers Interface Manual says that 
altivec registers 20-31 are to be saved by setjmp/longjmp on the SVR4 ABI.

--------------------------------------------------------------------------
Troy Benjegerdes                'da hozer'                hozer@drgw.net   

Somone asked my why I work on this free (http://www.fsf.org/philosophy/)
software stuff and not get a real job. Charles Shulz had the best answer:

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