Re: Altivec doesn't work?

[Jason Molenda <jmolenda at apple dot com>]

Daniel was correct that this isn't the right forum for Apple gdb  
questions.  Please send these kinds of things to xcode- 
users@lists.apple.com.

You'll want to be more specific about your program that isn't working  
under gdb.  For instance, this works fine with gdb-413:

#include <altivec.h>
int main () {
  vector unsigned int x = ((vector unsigned int) vec_splat_u8 (-2));
}

(gdb) p/x x
$2 = {0xfefefefe, 0xfefefefe, 0xfefefefe, 0xfefefefe}
(gdb)

Please follow up on xcode-users@ if you have any questions or  
problems with the Apple tools.  Thanks!

Jason

On Jul 16, 2005, at 11:00 AM, Décio Luiz Gazzoni Filho wrote:

> Hello,
>
> I have `GNU gdb 6.1-20040303 (Apple version gdb-413)' running on  
> Mac OS X 10.4.2. I wrote some Altivec code and tried to load it  
> into gdb. Although gdb can print the vector registers, they are not  
> updated by any instructions that are run: all regs stay at the  
> value 0x7FFFDEAD7FFFDEAD7FFFDEAD7FFFDEAD.
>
> I believe it's not a compilation issue, or a processor issue (mine  
> is an MPC7447). Outside of gdb, the code seems to run fine (doesn't  
> give an invalid instruction exception).
>
> This is my first foray into Altivec programming, so I'm wondering  
> what I'm missing here? This can't be a bug as Google doesn't turn  
> anything up.
>
> Décio