xcofflink.c

来自「基于4个mips核的noc设计」· C语言 代码 · 共 2,198 行 · 第 1/5 页

static boolean xcoff_mark PARAMS ((struct bfd_link_info *, asection *));
static void xcoff_sweep PARAMS ((struct bfd_link_info *));
static boolean xcoff_build_ldsyms
  PARAMS ((struct xcoff_link_hash_entry *, PTR));
static boolean xcoff_link_input_bfd
  PARAMS ((struct xcoff_final_link_info *, bfd *));
static boolean xcoff_write_global_symbol
  PARAMS ((struct xcoff_link_hash_entry *, PTR));
static boolean xcoff_reloc_link_order
  PARAMS ((bfd *, struct xcoff_final_link_info *, asection *,
	   struct bfd_link_order *));
static int xcoff_sort_relocs PARAMS ((const PTR, const PTR));

/* Routines to swap information in the XCOFF .loader section.  If we
   ever need to write an XCOFF loader, this stuff will need to be
   moved to another file shared by the linker (which XCOFF calls the
   ``binder'') and the loader.  */

/* Swap in the ldhdr structure.  */

static void
xcoff_swap_ldhdr_in (abfd, src, dst)
     bfd *abfd;
     const struct external_ldhdr *src;
     struct internal_ldhdr *dst;
{
  dst->l_version = bfd_get_32 (abfd, src->l_version);
  dst->l_nsyms = bfd_get_32 (abfd, src->l_nsyms);
  dst->l_nreloc = bfd_get_32 (abfd, src->l_nreloc);
  dst->l_istlen = bfd_get_32 (abfd, src->l_istlen);
  dst->l_nimpid = bfd_get_32 (abfd, src->l_nimpid);
  dst->l_impoff = bfd_get_32 (abfd, src->l_impoff);
  dst->l_stlen = bfd_get_32 (abfd, src->l_stlen);
  dst->l_stoff = bfd_get_32 (abfd, src->l_stoff);
}

/* Swap out the ldhdr structure.  */

static void
xcoff_swap_ldhdr_out (abfd, src, dst)
     bfd *abfd;
     const struct internal_ldhdr *src;
     struct external_ldhdr *dst;
{
  bfd_put_32 (abfd, src->l_version, dst->l_version);
  bfd_put_32 (abfd, src->l_nsyms, dst->l_nsyms);
  bfd_put_32 (abfd, src->l_nreloc, dst->l_nreloc);
  bfd_put_32 (abfd, src->l_istlen, dst->l_istlen);
  bfd_put_32 (abfd, src->l_nimpid, dst->l_nimpid);
  bfd_put_32 (abfd, src->l_impoff, dst->l_impoff);
  bfd_put_32 (abfd, src->l_stlen, dst->l_stlen);
  bfd_put_32 (abfd, src->l_stoff, dst->l_stoff);
}

/* Swap in the ldsym structure.  */

static void
xcoff_swap_ldsym_in (abfd, src, dst)
     bfd *abfd;
     const struct external_ldsym *src;
     struct internal_ldsym *dst;
{
  if (bfd_get_32 (abfd, src->_l._l_l._l_zeroes) != 0)
    memcpy (dst->_l._l_name, src->_l._l_name, SYMNMLEN);
  else
    {
      dst->_l._l_l._l_zeroes = 0;
      dst->_l._l_l._l_offset = bfd_get_32 (abfd, src->_l._l_l._l_offset);
    }
  dst->l_value = bfd_get_32 (abfd, src->l_value);
  dst->l_scnum = bfd_get_16 (abfd, src->l_scnum);
  dst->l_smtype = bfd_get_8 (abfd, src->l_smtype);
  dst->l_smclas = bfd_get_8 (abfd, src->l_smclas);
  dst->l_ifile = bfd_get_32 (abfd, src->l_ifile);
  dst->l_parm = bfd_get_32 (abfd, src->l_parm);
}

/* Swap out the ldsym structure.  */

static void
xcoff_swap_ldsym_out (abfd, src, dst)
     bfd *abfd;
     const struct internal_ldsym *src;
     struct external_ldsym *dst;
{
  if (src->_l._l_l._l_zeroes != 0)
    memcpy (dst->_l._l_name, src->_l._l_name, SYMNMLEN);
  else
    {
      bfd_put_32 (abfd, 0, dst->_l._l_l._l_zeroes);
      bfd_put_32 (abfd, src->_l._l_l._l_offset, dst->_l._l_l._l_offset);
    }
  bfd_put_32 (abfd, src->l_value, dst->l_value);
  bfd_put_16 (abfd, src->l_scnum, dst->l_scnum);
  bfd_put_8 (abfd, src->l_smtype, dst->l_smtype);
  bfd_put_8 (abfd, src->l_smclas, dst->l_smclas);
  bfd_put_32 (abfd, src->l_ifile, dst->l_ifile);
  bfd_put_32 (abfd, src->l_parm, dst->l_parm);
}

/* Swap in the ldrel structure.  */

static void
xcoff_swap_ldrel_in (abfd, src, dst)
     bfd *abfd;
     const struct external_ldrel *src;
     struct internal_ldrel *dst;
{
  dst->l_vaddr = bfd_get_32 (abfd, src->l_vaddr);
  dst->l_symndx = bfd_get_32 (abfd, src->l_symndx);
  dst->l_rtype = bfd_get_16 (abfd, src->l_rtype);
  dst->l_rsecnm = bfd_get_16 (abfd, src->l_rsecnm);
}

/* Swap out the ldrel structure.  */

static void
xcoff_swap_ldrel_out (abfd, src, dst)
     bfd *abfd;
     const struct internal_ldrel *src;
     struct external_ldrel *dst;
{
  bfd_put_32 (abfd, src->l_vaddr, dst->l_vaddr);
  bfd_put_32 (abfd, src->l_symndx, dst->l_symndx);
  bfd_put_16 (abfd, src->l_rtype, dst->l_rtype);
  bfd_put_16 (abfd, src->l_rsecnm, dst->l_rsecnm);
}

/* Routines to read XCOFF dynamic information.  This don't really
   belong here, but we already have the ldsym manipulation routines
   here.  */

/* Read the contents of a section.  */

static boolean
xcoff_get_section_contents (abfd, sec)
     bfd *abfd;
     asection *sec;
{
  if (coff_section_data (abfd, sec) == NULL)
    {
      sec->used_by_bfd = bfd_zalloc (abfd,
				     sizeof (struct coff_section_tdata));
      if (sec->used_by_bfd == NULL)
	return false;
    }

  if (coff_section_data (abfd, sec)->contents == NULL)
    {
      coff_section_data (abfd, sec)->contents =
	(bfd_byte *) bfd_malloc (sec->_raw_size);
      if (coff_section_data (abfd, sec)->contents == NULL)
	return false;

      if (! bfd_get_section_contents (abfd, sec,
				      coff_section_data (abfd, sec)->contents,
				      (file_ptr) 0, sec->_raw_size))
	return false;
    }

  return true;
}

/* Get the size required to hold the dynamic symbols.  */

long
_bfd_xcoff_get_dynamic_symtab_upper_bound (abfd)
     bfd *abfd;
{
  asection *lsec;
  bfd_byte *contents;
  struct internal_ldhdr ldhdr;

  if ((abfd->flags & DYNAMIC) == 0)
    {
      bfd_set_error (bfd_error_invalid_operation);
      return -1;
    }

  lsec = bfd_get_section_by_name (abfd, ".loader");
  if (lsec == NULL)
    {
      bfd_set_error (bfd_error_no_symbols);
      return -1;
    }

  if (! xcoff_get_section_contents (abfd, lsec))
    return -1;
  contents = coff_section_data (abfd, lsec)->contents;

  xcoff_swap_ldhdr_in (abfd, (struct external_ldhdr *) contents, &ldhdr);

  return (ldhdr.l_nsyms + 1) * sizeof (asymbol *);
}

/* Get the dynamic symbols.  */

long
_bfd_xcoff_canonicalize_dynamic_symtab (abfd, psyms)
     bfd *abfd;
     asymbol **psyms;
{
  asection *lsec;
  bfd_byte *contents;
  struct internal_ldhdr ldhdr;
  const char *strings;
  struct external_ldsym *elsym, *elsymend;
  coff_symbol_type *symbuf;

  if ((abfd->flags & DYNAMIC) == 0)
    {
      bfd_set_error (bfd_error_invalid_operation);
      return -1;
    }

  lsec = bfd_get_section_by_name (abfd, ".loader");
  if (lsec == NULL)
    {
      bfd_set_error (bfd_error_no_symbols);
      return -1;
    }

  if (! xcoff_get_section_contents (abfd, lsec))
    return -1;
  contents = coff_section_data (abfd, lsec)->contents;

  coff_section_data (abfd, lsec)->keep_contents = true;

  xcoff_swap_ldhdr_in (abfd, (struct external_ldhdr *) contents, &ldhdr);

  strings = (char *) contents + ldhdr.l_stoff;

  symbuf = ((coff_symbol_type *)
	    bfd_zalloc (abfd, ldhdr.l_nsyms * sizeof (coff_symbol_type)));
  if (symbuf == NULL)
    return -1;

  elsym = (struct external_ldsym *) (contents + LDHDRSZ);
  elsymend = elsym + ldhdr.l_nsyms;
  for (; elsym < elsymend; elsym++, symbuf++, psyms++)
    {
      struct internal_ldsym ldsym;

      xcoff_swap_ldsym_in (abfd, elsym, &ldsym);

      symbuf->symbol.the_bfd = abfd;

      if (ldsym._l._l_l._l_zeroes == 0)
	symbuf->symbol.name = strings + ldsym._l._l_l._l_offset;
      else
	{
	  int i;

	  for (i = 0; i < SYMNMLEN; i++)
	    if (ldsym._l._l_name[i] == '\0')
	      break;
	  if (i < SYMNMLEN)
	    symbuf->symbol.name = (char *) elsym->_l._l_name;
	  else
	    {
	      char *c;

	      c = bfd_alloc (abfd, SYMNMLEN + 1);
	      if (c == NULL)
		return -1;
	      memcpy (c, ldsym._l._l_name, SYMNMLEN);
	      c[SYMNMLEN] = '\0';
	      symbuf->symbol.name = c;
	    }
	}

      if (ldsym.l_smclas == XMC_XO)
	symbuf->symbol.section = bfd_abs_section_ptr;
      else
	symbuf->symbol.section = coff_section_from_bfd_index (abfd,
							      ldsym.l_scnum);
      symbuf->symbol.value = ldsym.l_value - symbuf->symbol.section->vma;

      symbuf->symbol.flags = BSF_NO_FLAGS;
      if ((ldsym.l_smtype & L_EXPORT) != 0)
	symbuf->symbol.flags |= BSF_GLOBAL;

      /* FIXME: We have no way to record the other information stored
         with the loader symbol.  */

      *psyms = (asymbol *) symbuf;
    }

  *psyms = NULL;

  return ldhdr.l_nsyms;
}

/* Get the size required to hold the dynamic relocs.  */

long
_bfd_xcoff_get_dynamic_reloc_upper_bound (abfd)
     bfd *abfd;
{
  asection *lsec;
  bfd_byte *contents;
  struct internal_ldhdr ldhdr;

  if ((abfd->flags & DYNAMIC) == 0)
    {
      bfd_set_error (bfd_error_invalid_operation);
      return -1;
    }

  lsec = bfd_get_section_by_name (abfd, ".loader");
  if (lsec == NULL)
    {
      bfd_set_error (bfd_error_no_symbols);
      return -1;
    }

  if (! xcoff_get_section_contents (abfd, lsec))
    return -1;
  contents = coff_section_data (abfd, lsec)->contents;

  xcoff_swap_ldhdr_in (abfd, (struct external_ldhdr *) contents, &ldhdr);

  return (ldhdr.l_nreloc + 1) * sizeof (arelent *);
}

/* The typical dynamic reloc.  */

static reloc_howto_type xcoff_dynamic_reloc =
  HOWTO (0,	                /* type */
	 0,	                /* rightshift */
	 2,	                /* size (0 = byte, 1 = short, 2 = long) */
	 32,	                /* bitsize */
	 false,	                /* pc_relative */
	 0,	                /* bitpos */
	 complain_overflow_bitfield, /* complain_on_overflow */
	 0,		        /* special_function */
	 "R_POS",               /* name */
	 true,	                /* partial_inplace */
	 0xffffffff,            /* src_mask */
	 0xffffffff,            /* dst_mask */
	 false);                /* pcrel_offset */

/* Get the dynamic relocs.  */

long
_bfd_xcoff_canonicalize_dynamic_reloc (abfd, prelocs, syms)
     bfd *abfd;
     arelent **prelocs;
     asymbol **syms;
{
  asection *lsec;
  bfd_byte *contents;
  struct internal_ldhdr ldhdr;
  arelent *relbuf;
  struct external_ldrel *elrel, *elrelend;

  if ((abfd->flags & DYNAMIC) == 0)
    {
      bfd_set_error (bfd_error_invalid_operation);
      return -1;
    }

  lsec = bfd_get_section_by_name (abfd, ".loader");
  if (lsec == NULL)
    {
      bfd_set_error (bfd_error_no_symbols);
      return -1;
    }

  if (! xcoff_get_section_contents (abfd, lsec))
    return -1;
  contents = coff_section_data (abfd, lsec)->contents;

  xcoff_swap_ldhdr_in (abfd, (struct external_ldhdr *) contents, &ldhdr);

  relbuf = (arelent *) bfd_alloc (abfd, ldhdr.l_nreloc * sizeof (arelent));
  if (relbuf == NULL)
    return -1;

  elrel = ((struct external_ldrel *)
	   (contents + LDHDRSZ + ldhdr.l_nsyms * LDSYMSZ));
  elrelend = elrel + ldhdr.l_nreloc;
  for (; elrel < elrelend; elrel++, relbuf++, prelocs++)
    {
      struct internal_ldrel ldrel;

      xcoff_swap_ldrel_in (abfd, elrel, &ldrel);

      if (ldrel.l_symndx >= 3)
	relbuf->sym_ptr_ptr = syms + (ldrel.l_symndx - 3);
      else
	{
	  const char *name;
	  asection *sec;

	  switch (ldrel.l_symndx)
	    {
	    case 0:
	      name = ".text";
	      break;
	    case 1:
	      name = ".data";
	      break;
	    case 2:
	      name = ".bss";
	      break;
	    default:
	      abort ();
	      break;
	    }

	  sec = bfd_get_section_by_name (abfd, name);
	  if (sec == NULL)
	    {
	      bfd_set_error (bfd_error_bad_value);
	      return -1;
	    }

	  relbuf->sym_ptr_ptr = sec->symbol_ptr_ptr;
	}

      relbuf->address = ldrel.l_vaddr;
      relbuf->addend = 0;

      /* Most dynamic relocs have the same type.  FIXME: This is only
         correct if ldrel.l_rtype == 0.  In other cases, we should use
         a different howto.  */
      relbuf->howto = &xcoff_dynamic_reloc;

      /* FIXME: We have no way to record the l_rsecnm field.  */

      *prelocs = relbuf;
    }

  *prelocs = NULL;

  return ldhdr.l_nreloc;
}

/* Routine to create an entry in an XCOFF link hash table.  */