elf32-fr30.c

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      x = (x & 0xff0f0000) | (relocation & 0x0000ffff) | ((relocation & 0x000f0000) << 4);
      bfd_put_32 (input_bfd, x, contents);
      break;

    case R_FR30_48:
      contents   += rel->r_offset + 2;
      relocation += rel->r_addend;
      bfd_put_32 (input_bfd, relocation, contents);
      break;

    case R_FR30_9_PCREL:
      contents   += rel->r_offset + 1;
      srel = (bfd_signed_vma) relocation;
      srel += rel->r_addend;
      srel -= rel->r_offset;
      srel -= 2;  /* Branch instructions add 2 to the PC...  */
      srel -= (input_section->output_section->vma +
		     input_section->output_offset);

      if (srel & 1)
	return bfd_reloc_outofrange;
      if (srel > ((1 << 8) - 1) || (srel < - (1 << 8)))
	return bfd_reloc_overflow;

      bfd_put_8 (input_bfd, srel >> 1, contents);
      break;

    case R_FR30_12_PCREL:
      contents   += rel->r_offset;
      srel = (bfd_signed_vma) relocation;
      srel += rel->r_addend;
      srel -= rel->r_offset;
      srel -= 2; /* Branch instructions add 2 to the PC...  */
      srel -= (input_section->output_section->vma +
		     input_section->output_offset);

      if (srel & 1)
	return bfd_reloc_outofrange;
      if (srel > ((1 << 11) - 1) || (srel < - (1 << 11)))
	  return bfd_reloc_overflow;

      x = bfd_get_16 (input_bfd, contents);
      x = (x & 0xf800) | ((srel >> 1) & 0x7ff);
      bfd_put_16 (input_bfd, x, contents);
      break;

    default:
      r = _bfd_final_link_relocate (howto, input_bfd, input_section,
				    contents, rel->r_offset,
				    relocation, rel->r_addend);
    }

  return r;
}

/* Relocate an FR30 ELF section.
   There is some attempt to make this function usable for many architectures,
   both USE_REL and USE_RELA ['twould be nice if such a critter existed],
   if only to serve as a learning tool.

   The RELOCATE_SECTION function is called by the new ELF backend linker
   to handle the relocations for a section.

   The relocs are always passed as Rela structures; if the section
   actually uses Rel structures, the r_addend field will always be
   zero.

   This function is responsible for adjusting the section contents as
   necessary, and (if using Rela relocs and generating a relocateable
   output file) adjusting the reloc addend as necessary.

   This function does not have to worry about setting the reloc
   address or the reloc symbol index.

   LOCAL_SYMS is a pointer to the swapped in local symbols.

   LOCAL_SECTIONS is an array giving the section in the input file
   corresponding to the st_shndx field of each local symbol.

   The global hash table entry for the global symbols can be found
   via elf_sym_hashes (input_bfd).

   When generating relocateable output, this function must handle
   STB_LOCAL/STT_SECTION symbols specially.  The output symbol is
   going to be the section symbol corresponding to the output
   section, which means that the addend must be adjusted
   accordingly.  */

static boolean
fr30_elf_relocate_section (output_bfd, info, input_bfd, input_section,
			   contents, relocs, local_syms, local_sections)
     bfd *                   output_bfd ATTRIBUTE_UNUSED;
     struct bfd_link_info *  info;
     bfd *                   input_bfd;
     asection *              input_section;
     bfd_byte *              contents;
     Elf_Internal_Rela *     relocs;
     Elf_Internal_Sym *      local_syms;
     asection **             local_sections;
{
  Elf_Internal_Shdr *           symtab_hdr;
  struct elf_link_hash_entry ** sym_hashes;
  Elf_Internal_Rela *           rel;
  Elf_Internal_Rela *           relend;

  symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
  sym_hashes = elf_sym_hashes (input_bfd);
  relend     = relocs + input_section->reloc_count;

  for (rel = relocs; rel < relend; rel ++)
    {
      reloc_howto_type *           howto;
      unsigned long                r_symndx;
      Elf_Internal_Sym *           sym;
      asection *                   sec;
      struct elf_link_hash_entry * h;
      bfd_vma                      relocation;
      bfd_reloc_status_type        r;
      const char *                 name = NULL;
      int                          r_type;

      r_type = ELF32_R_TYPE (rel->r_info);

      if (   r_type == R_FR30_GNU_VTINHERIT
	  || r_type == R_FR30_GNU_VTENTRY)
	continue;

      r_symndx = ELF32_R_SYM (rel->r_info);

      if (info->relocateable)
	{
	  /* This is a relocateable link.  We don't have to change
             anything, unless the reloc is against a section symbol,
             in which case we have to adjust according to where the
             section symbol winds up in the output section.  */
	  if (r_symndx < symtab_hdr->sh_info)
	    {
	      sym = local_syms + r_symndx;

	      if (ELF_ST_TYPE (sym->st_info) == STT_SECTION)
		{
		  sec = local_sections [r_symndx];
		  rel->r_addend += sec->output_offset + sym->st_value;
		}
	    }

	  continue;
	}

      /* This is a final link.  */
      howto  = fr30_elf_howto_table + ELF32_R_TYPE (rel->r_info);
      h      = NULL;
      sym    = NULL;
      sec    = NULL;

      if (r_symndx < symtab_hdr->sh_info)
	{
	  sym = local_syms + r_symndx;
	  sec = local_sections [r_symndx];
	  relocation = (sec->output_section->vma
			+ sec->output_offset
			+ sym->st_value);

	  name = bfd_elf_string_from_elf_section
	    (input_bfd, symtab_hdr->sh_link, sym->st_name);
	  name = (name == NULL) ? bfd_section_name (input_bfd, sec) : name;
#if 0
	  fprintf (stderr, "local: sec: %s, sym: %s (%d), value: %x + %x + %x addend %x\n",
		   sec->name, name, sym->st_name,
		   sec->output_section->vma, sec->output_offset,
		   sym->st_value, rel->r_addend);
#endif
	}
      else
	{
	  h = sym_hashes [r_symndx - symtab_hdr->sh_info];

	  while (h->root.type == bfd_link_hash_indirect
		 || h->root.type == bfd_link_hash_warning)
	    h = (struct elf_link_hash_entry *) h->root.u.i.link;

	  name = h->root.root.string;

	  if (h->root.type == bfd_link_hash_defined
	      || h->root.type == bfd_link_hash_defweak)
	    {
	      sec = h->root.u.def.section;
	      relocation = (h->root.u.def.value
			    + sec->output_section->vma
			    + sec->output_offset);
#if 0
	      fprintf (stderr,
		       "defined: sec: %s, name: %s, value: %x + %x + %x gives: %x\n",
		       sec->name, name, h->root.u.def.value,
		       sec->output_section->vma, sec->output_offset, relocation);
#endif
	    }
	  else if (h->root.type == bfd_link_hash_undefweak)
	    {
#if 0
	      fprintf (stderr, "undefined: sec: %s, name: %s\n",
		       sec->name, name);
#endif
	      relocation = 0;
	    }
	  else
	    {
	      if (! ((*info->callbacks->undefined_symbol)
		     (info, h->root.root.string, input_bfd,
		      input_section, rel->r_offset, true)))
		return false;
#if 0
	      fprintf (stderr, "unknown: name: %s\n", name);
#endif
	      relocation = 0;
	    }
	}

      r = fr30_final_link_relocate (howto, input_bfd, input_section,
				     contents, rel, relocation);

      if (r != bfd_reloc_ok)
	{
	  const char * msg = (const char *) NULL;

	  switch (r)
	    {
	    case bfd_reloc_overflow:
	      r = info->callbacks->reloc_overflow
		(info, name, howto->name, (bfd_vma) 0,
		 input_bfd, input_section, rel->r_offset);
	      break;

	    case bfd_reloc_undefined:
	      r = info->callbacks->undefined_symbol
		(info, name, input_bfd, input_section, rel->r_offset,
		 true);
	      break;

	    case bfd_reloc_outofrange:
	      msg = _("internal error: out of range error");
	      break;

	    case bfd_reloc_notsupported:
	      msg = _("internal error: unsupported relocation error");
	      break;

	    case bfd_reloc_dangerous:
	      msg = _("internal error: dangerous relocation");
	      break;

	    default:
	      msg = _("internal error: unknown error");
	      break;
	    }

	  if (msg)
	    r = info->callbacks->warning
	      (info, msg, name, input_bfd, input_section, rel->r_offset);

	  if (! r)
	    return false;
	}
    }

  return true;
}

/* Return the section that should be marked against GC for a given
   relocation.  */

static asection *
fr30_elf_gc_mark_hook (abfd, info, rel, h, sym)
     bfd *                        abfd;
     struct bfd_link_info *       info ATTRIBUTE_UNUSED;
     Elf_Internal_Rela *          rel;
     struct elf_link_hash_entry * h;
     Elf_Internal_Sym *           sym;
{
  if (h != NULL)
    {
      switch (ELF32_R_TYPE (rel->r_info))
	{
	case R_FR30_GNU_VTINHERIT:
	case R_FR30_GNU_VTENTRY:
	  break;

	default:
	  switch (h->root.type)
	    {
	    case bfd_link_hash_defined:
	    case bfd_link_hash_defweak:
	      return h->root.u.def.section;

	    case bfd_link_hash_common:
	      return h->root.u.c.p->section;

	    default:
	      break;
	    }
	}
    }
  else
    {
      if (!(elf_bad_symtab (abfd)
	    && ELF_ST_BIND (sym->st_info) != STB_LOCAL)
	  && ! ((sym->st_shndx <= 0 || sym->st_shndx >= SHN_LORESERVE)
		&& sym->st_shndx != SHN_COMMON))
	{
	  return bfd_section_from_elf_index (abfd, sym->st_shndx);
	}
    }

  return NULL;
}

/* Update the got entry reference counts for the section being removed.  */

static boolean
fr30_elf_gc_sweep_hook (abfd, info, sec, relocs)
     bfd *                     abfd ATTRIBUTE_UNUSED;
     struct bfd_link_info *    info ATTRIBUTE_UNUSED;
     asection *                sec ATTRIBUTE_UNUSED;
     const Elf_Internal_Rela * relocs ATTRIBUTE_UNUSED;
{
  return true;
}

/* Look through the relocs for a section during the first phase.
   Since we don't do .gots or .plts, we just need to consider the
   virtual table relocs for gc.  */

static boolean
fr30_elf_check_relocs (abfd, info, sec, relocs)
     bfd *abfd;
     struct bfd_link_info *info;
     asection *sec;
     const Elf_Internal_Rela *relocs;
{
  Elf_Internal_Shdr *symtab_hdr;
  struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
  const Elf_Internal_Rela *rel;
  const Elf_Internal_Rela *rel_end;

  if (info->relocateable)
    return true;

  symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
  sym_hashes = elf_sym_hashes (abfd);
  sym_hashes_end = sym_hashes + symtab_hdr->sh_size/sizeof (Elf32_External_Sym);
  if (!elf_bad_symtab (abfd))
    sym_hashes_end -= symtab_hdr->sh_info;

  rel_end = relocs + sec->reloc_count;
  for (rel = relocs; rel < rel_end; rel++)
    {
      struct elf_link_hash_entry *h;
      unsigned long r_symndx;

      r_symndx = ELF32_R_SYM (rel->r_info);
      if (r_symndx < symtab_hdr->sh_info)
        h = NULL;
      else
        h = sym_hashes[r_symndx - symtab_hdr->sh_info];

      switch (ELF32_R_TYPE (rel->r_info))
        {
        /* This relocation describes the C++ object vtable hierarchy.
           Reconstruct it for later use during GC.  */
        case R_FR30_GNU_VTINHERIT:
          if (!_bfd_elf32_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
            return false;
          break;

        /* This relocation describes which C++ vtable entries are actually
           used.  Record for later use during GC.  */
        case R_FR30_GNU_VTENTRY:
          if (!_bfd_elf32_gc_record_vtentry (abfd, sec, h, rel->r_addend))
            return false;
          break;
        }
    }

  return true;
}

#define ELF_ARCH		bfd_arch_fr30
#define ELF_MACHINE_CODE	EM_CYGNUS_FR30
#define ELF_MAXPAGESIZE		0x1000

#define TARGET_BIG_SYM          bfd_elf32_fr30_vec
#define TARGET_BIG_NAME		"elf32-fr30"

#define elf_info_to_howto_rel			NULL
#define elf_info_to_howto			fr30_info_to_howto_rela
#define elf_backend_relocate_section		fr30_elf_relocate_section
#define elf_backend_gc_mark_hook		fr30_elf_gc_mark_hook
#define elf_backend_gc_sweep_hook		fr30_elf_gc_sweep_hook
#define elf_backend_check_relocs                fr30_elf_check_relocs

#define elf_backend_can_gc_sections		1

#define bfd_elf32_bfd_reloc_type_lookup		fr30_reloc_type_lookup

#include "elf32-target.h"