[PATCH] D83462: [DWARF] Avoid entry_values production for SCE

[Eric Christopher via llvm-commits]

On Thu, Jul 9, 2020 at 2:01 PM Paul Robinson via Phabricator <
reviews at reviews.llvm.org> wrote:

> probinson added a comment.
>
> In D83462#2142036 <https://reviews.llvm.org/D83462#2142036>, @echristo
> wrote:
>
> > So the tuning here for SCE is also a "does not support" or something
> else?
>
>
> I'm told our debugger currently does not support the entry-value opcode.
> Locations with that opcode would be dropped/ignored (presumably just the
> individual location-list elements, although I haven't verified).
>
> I am nudging our folks in the direction of supporting it, but need to
> demonstrate value first; that the additional location descriptions increase
> availability, and that the expressions can be evaluated usefully.  I have
> to say a few preliminary experiments don't make me feel too positive about
> that second part, as the entry-value expressions tend to rely on registers
> that aren't saved by the ABI, so unwinding won't recover them.
>
> In the meantime I'd prefer that they weren't emitted. for the usual size
> reasons.
>

Totally. That sounds more like the "preference" rather than "we can't
support this part of dwarf5" that makes the command line difference for me
if that makes sense :)

-eric
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20200710/4a18bd62/attachment.html>