elf32-v850.c

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	 0xffff,			/* src_mask */
	 0xffff,			/* dst_mask */
	 false),			/* pcrel_offset */

  /* GNU extension to record C++ vtable hierarchy */
  HOWTO (R_V850_GNU_VTINHERIT, /* type */
         0,                     /* rightshift */
         2,                     /* size (0 = byte, 1 = short, 2 = long) */
         0,                     /* bitsize */
         false,                 /* pc_relative */
         0,                     /* bitpos */
         complain_overflow_dont, /* complain_on_overflow */
         NULL,                  /* special_function */
         "R_V850_GNU_VTINHERIT", /* name */
         false,                 /* partial_inplace */
         0,                     /* src_mask */
         0,                     /* dst_mask */
         false),                /* pcrel_offset */

  /* GNU extension to record C++ vtable member usage */
  HOWTO (R_V850_GNU_VTENTRY,     /* type */
         0,                     /* rightshift */
         2,                     /* size (0 = byte, 1 = short, 2 = long) */
         0,                     /* bitsize */
         false,                 /* pc_relative */
         0,                     /* bitpos */
         complain_overflow_dont, /* complain_on_overflow */
         _bfd_elf_rel_vtable_reloc_fn,  /* special_function */
         "R_V850_GNU_VTENTRY",   /* name */
         false,                 /* partial_inplace */
         0,                     /* src_mask */
         0,                     /* dst_mask */
         false),                /* pcrel_offset */

};

/* Map BFD reloc types to V850 ELF reloc types.  */

struct v850_elf_reloc_map
{
  /* BFD_RELOC_V850_CALLT_16_16_OFFSET is 258, which will not fix in an
     unsigned char.  */
  bfd_reloc_code_real_type bfd_reloc_val;
  unsigned char elf_reloc_val;
};

static const struct v850_elf_reloc_map v850_elf_reloc_map[] =
{
  { BFD_RELOC_NONE,		R_V850_NONE },
  { BFD_RELOC_V850_9_PCREL,	R_V850_9_PCREL },
  { BFD_RELOC_V850_22_PCREL,	R_V850_22_PCREL },
  { BFD_RELOC_HI16_S,		R_V850_HI16_S },
  { BFD_RELOC_HI16,		R_V850_HI16 },
  { BFD_RELOC_LO16,		R_V850_LO16 },
  { BFD_RELOC_32,		R_V850_32 },
  { BFD_RELOC_16,		R_V850_16 },
  { BFD_RELOC_8,		R_V850_8 },
  { BFD_RELOC_V850_SDA_16_16_OFFSET, R_V850_SDA_16_16_OFFSET },
  { BFD_RELOC_V850_SDA_15_16_OFFSET, R_V850_SDA_15_16_OFFSET },
  { BFD_RELOC_V850_ZDA_16_16_OFFSET, R_V850_ZDA_16_16_OFFSET },
  { BFD_RELOC_V850_ZDA_15_16_OFFSET, R_V850_ZDA_15_16_OFFSET },
  { BFD_RELOC_V850_TDA_6_8_OFFSET,   R_V850_TDA_6_8_OFFSET   },
  { BFD_RELOC_V850_TDA_7_8_OFFSET,   R_V850_TDA_7_8_OFFSET   },
  { BFD_RELOC_V850_TDA_7_7_OFFSET,   R_V850_TDA_7_7_OFFSET   },
  { BFD_RELOC_V850_TDA_16_16_OFFSET, R_V850_TDA_16_16_OFFSET },
  { BFD_RELOC_V850_TDA_4_5_OFFSET,         R_V850_TDA_4_5_OFFSET         },
  { BFD_RELOC_V850_TDA_4_4_OFFSET,         R_V850_TDA_4_4_OFFSET         },
  { BFD_RELOC_V850_SDA_16_16_SPLIT_OFFSET, R_V850_SDA_16_16_SPLIT_OFFSET },
  { BFD_RELOC_V850_ZDA_16_16_SPLIT_OFFSET, R_V850_ZDA_16_16_SPLIT_OFFSET },
  { BFD_RELOC_V850_CALLT_6_7_OFFSET,       R_V850_CALLT_6_7_OFFSET       },
  { BFD_RELOC_V850_CALLT_16_16_OFFSET,     R_V850_CALLT_16_16_OFFSET     },
  { BFD_RELOC_VTABLE_INHERIT,               R_V850_GNU_VTINHERIT },
  { BFD_RELOC_VTABLE_ENTRY,                 R_V850_GNU_VTENTRY },

};

/* Map a bfd relocation into the appropriate howto structure */
static reloc_howto_type *
v850_elf_reloc_type_lookup (abfd, code)
     bfd *                     abfd ATTRIBUTE_UNUSED;
     bfd_reloc_code_real_type  code;
{
  unsigned int i;

  for (i = 0;
       i < sizeof (v850_elf_reloc_map) / sizeof (struct v850_elf_reloc_map);
       i++)
    {
      if (v850_elf_reloc_map[i].bfd_reloc_val == code)
	{
	  BFD_ASSERT (v850_elf_howto_table[v850_elf_reloc_map[i].elf_reloc_val].type == v850_elf_reloc_map[i].elf_reloc_val);

	  return & v850_elf_howto_table[v850_elf_reloc_map[i].elf_reloc_val];
	}
    }

  return NULL;
}

/* Set the howto pointer for an V850 ELF reloc.  */
static void
v850_elf_info_to_howto_rel (abfd, cache_ptr, dst)
     bfd *                 abfd ATTRIBUTE_UNUSED;
     arelent *             cache_ptr;
     Elf32_Internal_Rel *  dst;
{
  unsigned int r_type;

  r_type = ELF32_R_TYPE (dst->r_info);
  BFD_ASSERT (r_type < (unsigned int) R_V850_max);
  cache_ptr->howto = &v850_elf_howto_table[r_type];
}

/* Set the howto pointer for a V850 ELF reloc (type RELA).  */
static void
v850_elf_info_to_howto_rela (abfd, cache_ptr, dst)
     bfd *                 abfd ATTRIBUTE_UNUSED;
     arelent *             cache_ptr;
     Elf32_Internal_Rela   *dst;
{
  unsigned int r_type;

  r_type = ELF32_R_TYPE (dst->r_info);
  BFD_ASSERT (r_type < (unsigned int) R_V850_max);
  cache_ptr->howto = &v850_elf_howto_table[r_type];
}

/* Look through the relocs for a section during the first phase, and
   allocate space in the global offset table or procedure linkage
   table.  */

static boolean
v850_elf_check_relocs (abfd, info, sec, relocs)
     bfd *                      abfd;
     struct bfd_link_info *     info;
     asection *                 sec;
     const Elf_Internal_Rela *  relocs;
{
  boolean ret = true;
  bfd *dynobj;
  Elf_Internal_Shdr *symtab_hdr;
  struct elf_link_hash_entry **sym_hashes;
  const Elf_Internal_Rela *rel;
  const Elf_Internal_Rela *rel_end;
  asection *sreloc;
  enum v850_reloc_type r_type;
  int other = 0;
  const char *common = (const char *)0;

  if (info->relocateable)
    return true;

#ifdef DEBUG
  fprintf (stderr, "v850_elf_check_relocs called for section %s in %s\n",
	   bfd_get_section_name (abfd, sec),
	   bfd_get_filename (abfd));
#endif

  dynobj = elf_hash_table (info)->dynobj;
  symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
  sym_hashes = elf_sym_hashes (abfd);
  sreloc = NULL;

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

      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];

      r_type = (enum v850_reloc_type) ELF32_R_TYPE (rel->r_info);
      switch (r_type)
	{
	default:
	case R_V850_NONE:
	case R_V850_9_PCREL:
	case R_V850_22_PCREL:
	case R_V850_HI16_S:
	case R_V850_HI16:
	case R_V850_LO16:
	case R_V850_32:
	case R_V850_16:
	case R_V850_8:
	case R_V850_CALLT_6_7_OFFSET:
	case R_V850_CALLT_16_16_OFFSET:
	  break;

        /* This relocation describes the C++ object vtable hierarchy.
           Reconstruct it for later use during GC.  */
        case R_V850_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_V850_GNU_VTENTRY:
          if (!_bfd_elf32_gc_record_vtentry (abfd, sec, h, rel->r_addend))
            return false;
          break;

	case R_V850_SDA_16_16_SPLIT_OFFSET:
	case R_V850_SDA_16_16_OFFSET:
	case R_V850_SDA_15_16_OFFSET:
	  other = V850_OTHER_SDA;
	  common = ".scommon";
	  goto small_data_common;

	case R_V850_ZDA_16_16_SPLIT_OFFSET:
	case R_V850_ZDA_16_16_OFFSET:
	case R_V850_ZDA_15_16_OFFSET:
	  other = V850_OTHER_ZDA;
	  common = ".zcommon";
	  goto small_data_common;

	case R_V850_TDA_4_5_OFFSET:
	case R_V850_TDA_4_4_OFFSET:
	case R_V850_TDA_6_8_OFFSET:
	case R_V850_TDA_7_8_OFFSET:
	case R_V850_TDA_7_7_OFFSET:
	case R_V850_TDA_16_16_OFFSET:
	  other = V850_OTHER_TDA;
	  common = ".tcommon";
	  /* fall through */

#define V850_OTHER_MASK (V850_OTHER_TDA | V850_OTHER_SDA | V850_OTHER_ZDA)

	small_data_common:
	  if (h)
	    {
	      h->other |= other;	/* flag which type of relocation was used */
	      if ((h->other & V850_OTHER_MASK) != (other & V850_OTHER_MASK)
		  && (h->other & V850_OTHER_ERROR) == 0)
		{
		  const char * msg;
		  static char  buff[200]; /* XXX */

		  switch (h->other & V850_OTHER_MASK)
		    {
		    default:
		      msg = _("Variable `%s' cannot occupy in multiple small data regions");
		      break;
		    case V850_OTHER_SDA | V850_OTHER_ZDA | V850_OTHER_TDA:
		      msg = _("Variable `%s' can only be in one of the small, zero, and tiny data regions");
		      break;
		    case V850_OTHER_SDA | V850_OTHER_ZDA:
		      msg = _("Variable `%s' cannot be in both small and zero data regions simultaneously");
		      break;
		    case V850_OTHER_SDA | V850_OTHER_TDA:
		      msg = _("Variable `%s' cannot be in both small and tiny data regions simultaneously");
		      break;
		    case V850_OTHER_ZDA | V850_OTHER_TDA:
		      msg = _("Variable `%s' cannot be in both zero and tiny data regions simultaneously");
		      break;
		    }

		  sprintf (buff, msg, h->root.root.string);
		  info->callbacks->warning (info, buff, h->root.root.string,
					    abfd, h->root.u.def.section, 0);

		  bfd_set_error (bfd_error_bad_value);
		  h->other |= V850_OTHER_ERROR;
		  ret = false;
		}
	    }

	  if (h && h->root.type == bfd_link_hash_common
	      && h->root.u.c.p
	      && !strcmp (bfd_get_section_name (abfd, h->root.u.c.p->section), "COMMON"))
	    {
	      asection *section = h->root.u.c.p->section = bfd_make_section_old_way (abfd, common);
	      section->flags |= SEC_IS_COMMON;
	    }

#ifdef DEBUG
	  fprintf (stderr, "v850_elf_check_relocs, found %s relocation for %s%s\n",
		   v850_elf_howto_table[ (int)r_type ].name,
		   (h && h->root.root.string) ? h->root.root.string : "<unknown>",
		   (h->root.type == bfd_link_hash_common) ? ", symbol is common" : "");
#endif
	  break;
	}
    }

  return ret;
}

/*
 * In the old version, when an entry was checked out from the table,
 * it was deleted.  This produced an error if the entry was needed
 * more than once, as the second attempted retry failed.
 *
 * In the current version, the entry is not deleted, instead we set
 * the field 'found' to true.  If a second lookup matches the same
 * entry, then we know that the hi16s reloc has already been updated
 * and does not need to be updated a second time.
 *
 * TODO - TOFIX: If it is possible that we need to restore 2 different
 * addresses from the same table entry, where the first generates an
 * overflow, whilst the second do not, then this code will fail.
 */

typedef struct hi16s_location
{
  bfd_vma       addend;
  bfd_byte *    address;
  unsigned long counter;
  boolean       found;
  struct hi16s_location * next;
}
hi16s_location;

static hi16s_location *  previous_hi16s;
static hi16s_location *  free_hi16s;
static unsigned long     hi16s_counter;

static void
remember_hi16s_reloc (abfd, addend, address)
     bfd *      abfd;
     bfd_vma    addend;
     bfd_byte * address;
{
  hi16s_location * entry = NULL;

  /* Find a free structure.  */
  if (free_hi16s == NULL)
    free_hi16s = (hi16s_location *) bfd_zalloc (abfd, sizeof (* free_hi16s));

  entry      = free_hi16s;
  free_hi16s = free_hi16s->next;

  entry->addend  = addend;
  entry->address = address;
  entry->counter = hi16s_counter ++;
  entry->found   = false;
  entry->next    = previous_hi16s;
  previous_hi16s = entry;

  /* Cope with wrap around of our counter.  */
  if (hi16s_counter == 0)
    {
      /* XXX - Assume that all counter entries differ only in their low 16 bits.  */
      for (entry = previous_hi16s; entry != NULL; entry = entry->next)
	entry->counter &= 0xffff;

      hi16s_counter = 0x10000;
    }

  return;
}

static bfd_byte *
find_remembered_hi16s_reloc (addend, already_found)
     bfd_vma   addend;
     boolean * already_found;
{
  hi16s_location * match = NULL;
  hi16s_location * entry;
  hi16s_location * previous = NULL;
  hi16s_location * prev;
  bfd_byte *       addr;

  /* Search the table.  Record the most recent entry that matches.  */
  for (entry = previous_hi16s; entry; entry = entry->next)
    {
      if (entry->addend == addend
	  && (match == NULL || match->counter < entry->counter))
	{
	  previous = prev;
	  match    = entry;
	}

      prev = entry;
    }

  if (match == NULL)
    return NULL;

  /* Extract the address.  */
  addr = match->address;

  /* Remeber if this entry has already been used before.  */
  if (already_found)
    * already_found = match->found;

  /* Note that this entry has now been used.  */
  match->found = true;

  return addr;
}

/* FIXME:  The code here probably ought to be removed and the code in reloc.c
   allowed to do its  stuff instead.  At least for most of the relocs, anwyay.  */
static bfd_reloc_status_type
v850_elf_perform_relocation (abfd, r_type, addend, address)
     bfd *      abfd;
     int        r_type;
     bfd_vma    addend;
     bfd_byte * address;
{
  unsigned long insn;
  bfd_signed_vma saddend = (bfd_signed_vma) addend;

  switch (r_type)
    {
    default:
      /* fprintf (stderr, "reloc type %d not SUPPORTED\n", r_type ); */
      return bfd_reloc_notsupported;

    case R_V850_32:
      bfd_put_32 (abfd, addend, address);
      return bfd_reloc_ok;

    case R_V850_22_PCREL:
      if (saddend > 0x1fffff || saddend < -0x200000)
	return bfd_reloc_overflow;

      if ((addend % 2) != 0)
	return bfd_reloc_dangerous;

      insn  = bfd_get_32 (abfd, address);
      insn &= ~0xfffe003f;
      insn |= (((addend & 0xfffe) << 16) | ((addend & 0x3f0000) >> 16));
      bfd_put_32 (abfd, insn, address);