propose to tighten condition for calls of _bfd_riscv_table_jump_mark for R_RISCV_CALL/R_RISCV_CALL_PLT/R_RISCV_JAL only

[JoshCafe]

hi

https://github.com/openhwgroup/corev-binutils-gdb/blob/development/bfd/elfnn-riscv.c

In relax pass 0 and relax_trip 2 of _bfd_riscv_relax_section, if table jump can save size, and then we replace all targeted
instructions/instruction pairs(e.g. auipc+jalr or jal) to zcmt instructions by _bfd_riscv_table_jump_mark function.

But seems we try to call _bfd_riscv_table_jump_mark for all kinds of relocation types, which exposes a risk to replace an un-targeted instruction with a zcmt instruction.

So propose to tighten condition for calls of _bfd_riscv_table_jump_mark for R_RISCV_CALL/R_RISCV_CALL_PLT/R_RISCV_JAL only.

      relax_func = NULL;
      if (info->relax_pass == 0)
	{
	  if (!riscv_use_table_jump (info))
	    return true;

	  if (info->relax_trip == 0)
	    {
	      if (type == R_RISCV_CALL
		  || type == R_RISCV_CALL_PLT)
		relax_func = _bfd_riscv_relax_call;
	      else if (type == R_RISCV_JAL)
		relax_func = _bfd_riscv_record_jal;
	      else
		continue;
	      *again = true;
	    }
	  else if (info->relax_trip == 2) //  tighten condition for  R_RISCV_CALL/R_RISCV_CALL_PLT/R_RISCV_JAL only
	    relax_func = _bfd_riscv_table_jump_mark;
	}

[pz9115]

Yes, that's a question, I think it a good propose.

[pz9115]

Fix in #83.