[RFA] Limited DW_OP_piece support

[Daniel Jacobowitz]

On Thu, May 22, 2003 at 10:00:39AM -0700, Kevin Buettner wrote:
> The patch below adds limited DW_OP_piece support to dwarf2expr.c.  I
> will post a patch to rs6000-tdep.c which illustrates what a
> ``dwarf2_compose_register_pieces'' method should look like.
> 
> Okay?

I would really strongly prefer that we not do it this way.

You'll notice that there are no other gdbarch calls in the expression
evaluator.  There might be some implicit ones through macros, for
instance there is TARGET_ADDR_BIT.  That needs to be fixed properly
some day already.

Instead, IMHO, we should devise a way to represent multiple locations
in the evaluator's return value.  This is not suggesting the complete
overhaul that we need to support multiple locations in the rest of GDB.
Then have the expression evaluator properly return a list of locations,
and have the massaging done via gdbarch in the evaluator's client. 
Does that sound reasonable?

Maybe a flag to the evaluator which says whether we're looking for a
location, for better sanity checking.  Not sure about that part.

-- 
Daniel Jacobowitz
MontaVista Software                         Debian GNU/Linux Developer