* elfxx-mips.c (mips_elf_calculate_relocation): For R_MIPS_JALR,

return a real value, unless it is a PLT symbol.
	(mips_elf_perform_relocation): On the RM9000, turn a jal into a
	bal if possible.
This commit is contained in:
Ian Lance Taylor 2004-12-09 07:12:28 +00:00
parent 74f79d8d75
commit 1367d393bb
2 changed files with 40 additions and 4 deletions

View File

@ -1,5 +1,10 @@
2004-12-09 Ian Lance Taylor <ian@wasabisystems.com>
* elfxx-mips.c (mips_elf_calculate_relocation): For R_MIPS_JALR,
return a real value, unless it is a PLT symbol.
(mips_elf_perform_relocation): On the RM9000, turn a jal into a
bal if possible.
* elfn32-mips.c (elf_mips_howto_table_rela): Change dst_mask of
R_MIPS_JALR entry to 0.

View File

@ -3523,12 +3523,16 @@ mips_elf_calculate_relocation (bfd *abfd, bfd *input_bfd,
value &= howto->dst_mask;
break;
case R_MIPS_PJUMP:
case R_MIPS_JALR:
/* Both of these may be ignored. R_MIPS_JALR is an optimization
hint; we could improve performance by honoring that hint. */
return bfd_reloc_continue;
/* This relocation is only a hint. In some cases, we optimize
it into a bal instruction. But we don't try to optimize
branches to the PLT; that will wind up wasting time. */
if (h != NULL && h->root.plt.offset != (bfd_vma) -1)
return bfd_reloc_continue;
value = symbol + addend;
break;
case R_MIPS_PJUMP:
case R_MIPS_GNU_VTINHERIT:
case R_MIPS_GNU_VTENTRY:
/* We don't do anything with these at present. */
@ -3730,6 +3734,33 @@ mips_elf_perform_relocation (struct bfd_link_info *info,
x = (x & ~(0x3f << 26)) | (jalx_opcode << 26);
}
/* On the RM9000, bal is faster than jal, because bal uses branch
prediction hardware. If we are linking for the RM9000, and we
see jal, and bal fits, use it instead. Note that this
transformation should be safe for all architectures. */
if (bfd_get_mach (input_bfd) == bfd_mach_mips9000
&& !info->relocatable
&& !require_jalx
&& ((r_type == R_MIPS_26 && (x >> 26) == 0x3) /* jal addr */
|| (r_type == R_MIPS_JALR && x == 0x0320f809))) /* jalr t9 */
{
bfd_vma addr;
bfd_vma dest;
bfd_signed_vma off;
addr = (input_section->output_section->vma
+ input_section->output_offset
+ relocation->r_offset
+ 4);
if (r_type == R_MIPS_26)
dest = (value << 2) | ((addr >> 28) << 28);
else
dest = value;
off = dest - addr;
if (off <= 0x1ffff && off >= -0x20000)
x = 0x04110000 | (((bfd_vma) off >> 2) & 0xffff); /* bal addr */
}
/* Swap the high- and low-order 16 bits on little-endian systems
when doing a MIPS16 relocation. */
if ((r_type == R_MIPS16_GPREL || r_type == R_MIPS16_26)