[LLVMdev] MCFixup for distance from instruction to end of .text section

[Tim Northover]

Hi Tom,

On 12 July 2014 22:52, Tom Stellard <tom at stellard.net> wrote:
> I would like to use a MCFixup to encode the distance in number of bytes
> from an instruction to the end of the .text section.  Is there an
> existing MCFixup type I can use for this?  If not, does anyone have any
> suggestions for how to add a new MCFixup type that will do this?

If that end-point is going to be resolved at compile-time, I think
we'd usually create a dummy (local) label and then emit it at the
correct place; you'd probably just need a generic FK_PCRel_N fixup.

Otherwise, it's probably a target-specific FixupKind that gets emitted
as a relocation and some assembly syntax that you make up. I suppose
you could do the same trick with a real symbol and demand that the
linker defines it (similar to how "_GLOBAL_OFFSET_TABLE_" gets
defined, for example).

Cheers.

Tim.