Relocations on branches

[Daniel P. Volpato]

Hi,

I am doing some experiments with binutils and have a doubt.
Is it possible to create PC-relative relocations for branches, so that
these can be resolved at link time?

What I mean is: instead of having this:

   8:    00051880     sll    v1,a1,0x2
   c:    24c20000     addiu    v0,a2,0
            c: R_MIPS_LO16    b
  ...
  24:    1480fff8     bnez    a0,8 <workOnB+0x8>

the instruction at 0x24 would be modified and a relocation installed,
something similar to the one at 0x0c:

   8:    00051880     sll    v1,a1,0x2
   c:    24c20000     addiu    v0,a2,0
            c: R_MIPS_LO16    b
  ...
  24:    1480fff8     bnez    a0,0
            24: <PC_REL_RELOC> value

I did some digging on my own at this mailing list and at GCC's and, if
I get it right, this is not possible in some architectures - e.g.
MIPS, although the PC-relative relocations type exists
(BFD_RELOC_16_PCREL and others). Is that right?

Thanks,
Daniel