[PATCH] [MIPS] Ensure that local GOT entries accessed via a 16-bit index come first

[Maciej W. Rozycki]

On Thu, 17 Apr 2014, Richard Sandiford wrote:

> GCC doesn't produce them.  I agree using GOT_PAGE/HI16 seems unlikely,
> especially since the sequence to load an address would then require 3
> instructions.  I imagine in practice everyone just uses GOT_{HI,LO}16
> for all ABIs.

 Yeah, as observed here and the cause of the issue we support 
GOT_HI16/GOT_LO16 pairs (and also actually GOT16 with no LO16 counterpart) 
for local symbols as well, making GOT_DISP redundant.  And for GOT_PAGE we 
have almost 16k pages worth 1GB of program space available before 
GOT_PAGE/HI16 would load non-zero.

> I don't think this was your point, but just in case: even if something
> did use those in future, the patch is still a strict improvement over
> the current situation, in that it handles {GOT,CALL}_{HI,LO}16 better
> without changing the allocation scheme for the others.  I don't think
> we should add extra code for compound GOT relocs without a patch to make
> GCC use them (which I'm not convinced is a good idea).

 Of course it was not, the change is excellent work -- thanks, Kwok.

  Maciej