[patchv2 3/4] unwinder: ppc and ppc64

Mark Wielaard mjw at redhat.com
Thu Dec 5 21:25:34 UTC 2013


On Tue, 2013-12-03 at 14:09 +0100, Jan Kratochvil wrote:
> The patch seems ready to me, it just waits for the review of:
> 	jankratochvil/ppc64bidir

Yes, the patch seems OK, please just checkin the non-tests parts that
don't depend on the ppc64bidir stuff.

> On Fri, 29 Nov 2013 11:32:08 +0100, Mark Wielaard wrote:
> > Aha, yes of course, "nip" isn't associated with any regno. I think I
> > would have used the "nip" name as marker or maybe introduced a
> > "fake/special" regno for it. Instead of adding a new pc_register boolean
> > field to every register to save a little space, but I guess this works
> > too and there aren't so many registers that it really matters.
> 
> It is ugly to add named-exceptions in the code.

yeah, I guess if you cannot describe "nip" as part of a
Register_Location then in this case special casing on the name of a note
item in generic code is ugly.

Thanks for adding the various comments.

> > OK, but just below this code is another loop over the items/regs which
> > contains some FIXMEs that you seem to have fixed now. Can't these loops
> > be combined? It currently seems to duplicate the value extraction code
> > and seems to depend on the order of notes/items. It would be better if
> > it was just one loop that only depended on the regno (and/or pc_register
> > flag or special PC name).
> 
> This new Ebl_Core_Item based code is unrelated to the Ebl_Register_Location
> code below it.  The Ebl_Core_Item code above sets PC register which has no
> DWARF register number.  The Ebl_Register_Location code below sets LR register
> which has either 65 or 108 DWARF register number.
> 
> The Ebl_Register_Location hack there is ugly but it is unrelated to the code
> above.

Right, by mistake. I was hoping there was a way to make "nip" being part
of the Register_Locations. But it isn't. It is described as part of a
note item. Which are enumerated separately.

Thanks,

Mark




More information about the elfutils-devel mailing list