Re: [Dwarf Patch] Improve pubnames and pubtypes generation. (issue 6197069)

[Cary Coutant <ccoutant@google.com>]

> Yes, but I would expect this table lookup to be faster than going to the
> disk to read the CU DIE and abbrev in order to check for the attribute.
>  OTOH, I suppose you need to read it anyway if you want to check somehow
> whether you should trust the pub* information.

Right. I also need to read the top-level DIE to get the range list for the CU.

>> Building
>> the .gdb_index in gold is still too slow, but these attributes help
>> make it a bit faster than it was without them.
>>
>> Are these two attributes a showstopper issue for you?
>
> No, I'm just reluctant to add more relocations.  Could we make them just
> flags?

That might be workable. Let me take a look at the gold changes I'd
need to make for that.

They don't have to be relocations, though -- since they're only used
by the linker, a raw section-relative offset would be sufficient.

>> Yes, I understand that's broken, but there are no consumers at this
>> point that make any use of that offset. Would it be acceptable if we
>> just put 0 there? (Given that I expect .debug_pub* to go away soon, I
>> don't think it's worth the trouble of filling in the offset with
>> anything more meaningful.)
>
> I wouldn't expect it to be much harder to put the skeleton there than plain
> 0.

I was concerned that we might not always have a skeleton type to point
to, but I confess I haven't looked closely enough to know whether
that's a valid concern.

-cary