/* AVR-specific support for 32-bit ELF
Copyright 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
- 2010 Free Software Foundation, Inc.
+ 2010, 2011 Free Software Foundation, Inc.
Contributed by Denis Chertykov <denisc@overta.ru>
This file is part of BFD, the Binary File Descriptor library.
bfd_vma symval;
bfd_vma shrinked_insn_address;
+ if (isec->reloc_count == 0)
+ continue;
+
shrinked_insn_address = (sec->output_section->vma
+ sec->output_offset + addr - count);
- irelend = elf_section_data (isec)->relocs + isec->reloc_count;
- for (irel = elf_section_data (isec)->relocs;
+ irel = elf_section_data (isec)->relocs;
+ /* PR 12161: Read in the relocs for this section if necessary. */
+ if (irel == NULL)
+ irel = _bfd_elf_link_read_relocs (abfd, isec, NULL, NULL, FALSE);
+
+ for (irelend = irel + isec->reloc_count;
irel < irelend;
irel++)
{
/* else...Reference symbol is extern. No need for adjusting
the addend. */
}
+
+ if (elf_section_data (isec)->relocs == NULL)
+ free (irelend - isec->reloc_count);
}
}
Elf_Internal_Sym *isymbuf = NULL;
struct elf32_avr_link_hash_table *htab;
+ /* If 'shrinkable' is FALSE, do not shrink by deleting bytes while
+ relaxing. Such shrinking can cause issues for the sections such
+ as .vectors and .jumptables. Instead the unused bytes should be
+ filled with nop instructions. */
+ bfd_boolean shrinkable = TRUE;
+
+ if (!strcmp (sec->name,".vectors")
+ || !strcmp (sec->name,".jumptables"))
+ shrinkable = FALSE;
+
if (link_info->relocatable)
(*link_info->callbacks->einfo)
(_("%P%F: --relax and -r may not be used together\n"));
/* Compute the distance from this insn to the branch target. */
gap = value - dot;
- /* If the distance is within -4094..+4098 inclusive, then we can
- relax this jump/call. +4098 because the call/jump target
- will be closer after the relaxation. */
- if ((int) gap >= -4094 && (int) gap <= 4098)
+ /* Check if the gap falls in the range that can be accommodated
+ in 13bits signed (It is 12bits when encoded, as we deal with
+ word addressing). */
+ if (!shrinkable && ((int) gap >= -4096 && (int) gap <= 4095))
+ distance_short_enough = 1;
+ /* If shrinkable, then we can check for a range of distance which
+ is two bytes farther on both the directions because the call
+ or jump target will be closer by two bytes after the
+ relaxation. */
+ else if (shrinkable && ((int) gap >= -4094 && (int) gap <= 4097))
distance_short_enough = 1;
/* Here we handle the wrap-around case. E.g. for a 16k device
irel->r_info = ELF32_R_INFO (ELF32_R_SYM (irel->r_info),
R_AVR_13_PCREL);
- /* Check for the vector section. There we don't want to
- modify the ordering! */
-
- if (!strcmp (sec->name,".vectors")
- || !strcmp (sec->name,".jumptables"))
+ /* We should not modify the ordering if 'shrinkable' is
+ FALSE. */
+ if (!shrinkable)
{
/* Let's insert a nop. */
bfd_put_8 (abfd, 0x00, contents + irel->r_offset + 2);
if ((0x95 == next_insn_msb) && (0x08 == next_insn_lsb))
{
/* The next insn is a ret. We possibly could delete
- this ret. First we need to check for preceeding
+ this ret. First we need to check for preceding
sbis/sbic/sbrs or cpse "skip" instructions. */
- int there_is_preceeding_non_skip_insn = 1;
+ int there_is_preceding_non_skip_insn = 1;
bfd_vma address_of_ret;
address_of_ret = dot + insn_size;
printf ("found jmp / ret sequence at address 0x%x\n",
(int) dot);
- /* We have to make sure that there is a preceeding insn. */
+ /* We have to make sure that there is a preceding insn. */
if (irel->r_offset >= 2)
{
- unsigned char preceeding_msb;
- unsigned char preceeding_lsb;
- preceeding_msb =
+ unsigned char preceding_msb;
+ unsigned char preceding_lsb;
+
+ preceding_msb =
bfd_get_8 (abfd, contents + irel->r_offset - 1);
- preceeding_lsb =
+ preceding_lsb =
bfd_get_8 (abfd, contents + irel->r_offset - 2);
/* sbic. */
- if (0x99 == preceeding_msb)
- there_is_preceeding_non_skip_insn = 0;
+ if (0x99 == preceding_msb)
+ there_is_preceding_non_skip_insn = 0;
/* sbis. */
- if (0x9b == preceeding_msb)
- there_is_preceeding_non_skip_insn = 0;
+ if (0x9b == preceding_msb)
+ there_is_preceding_non_skip_insn = 0;
/* sbrc */
- if ((0xfc == (preceeding_msb & 0xfe)
- && (0x00 == (preceeding_lsb & 0x08))))
- there_is_preceeding_non_skip_insn = 0;
+ if ((0xfc == (preceding_msb & 0xfe)
+ && (0x00 == (preceding_lsb & 0x08))))
+ there_is_preceding_non_skip_insn = 0;
/* sbrs */
- if ((0xfe == (preceeding_msb & 0xfe)
- && (0x00 == (preceeding_lsb & 0x08))))
- there_is_preceeding_non_skip_insn = 0;
+ if ((0xfe == (preceding_msb & 0xfe)
+ && (0x00 == (preceding_lsb & 0x08))))
+ there_is_preceding_non_skip_insn = 0;
/* cpse */
- if (0x10 == (preceeding_msb & 0xfc))
- there_is_preceeding_non_skip_insn = 0;
+ if (0x10 == (preceding_msb & 0xfc))
+ there_is_preceding_non_skip_insn = 0;
- if (there_is_preceeding_non_skip_insn == 0)
+ if (there_is_preceding_non_skip_insn == 0)
if (debug_relax)
- printf ("preceeding skip insn prevents deletion of"
- " ret insn at addr 0x%x in section %s\n",
+ printf ("preceding skip insn prevents deletion of"
+ " ret insn at Addy 0x%x in section %s\n",
(int) dot + 2, sec->name);
}
else
{
/* There is no previous instruction. */
- there_is_preceeding_non_skip_insn = 0;
+ there_is_preceding_non_skip_insn = 0;
}
- if (there_is_preceeding_non_skip_insn)
+ if (there_is_preceding_non_skip_insn)
{
/* We now only have to make sure that there is no
local label defined at the address of the ret