Re: Printing decimal128 types out of registers

[Thiago Jung Bauermann <bauerman@br.ibm.com>]

Hi,

Luis is on vacation at the moment, so I'll answer this for him...

On Fri, 2008-01-18 at 19:04 -0500, Daniel Jacobowitz wrote:
> If the feature is not going to contain anything, I think it should be
> a property of the floating point feature rather than an independent
> feature - one which says "interpret these FP registers as DFP also",
> <property name="dfp-registers"></property> or something similar.
> 
> That's how I would handle MMX versus SSE.  However, since there is a
> useful software implementation that uses the same registers, Mark is
> right - we can just show them all the time.

Yes, even for software decimal float implementations the calling
convention for PowerPC. is to put _Decimal128 in a pair of float
registers

I was talking to Luis about this, and he suggested an approach other
than using pseudo registers: create a way to make GDB consider two
consecutive registers as contiguous data. Since there are other types
that are also passed in consecutive registers (e.g., long long,
soft-float, IBM lon double), this mechanism would be more useful. I
think this is a good idea.

Perhaps some syntax could be created, like:

(gdb) print {_Decimal128} $f2,$f3
$1 = 1.2

What do you think?
-- 
[]'s
Thiago Jung Bauermann
Software Engineer
IBM Linux Technology Center