riscix.c

基于4个mips核的noc设计

     check for that here
     */

  if (bfd_is_com_section (output_section)
      || output_section == &bfd_abs_section
      || output_section == &bfd_und_section)
    {
      if (bfd_abs_section.symbol == sym)
	{
	  /* Whoops, looked like an abs symbol, but is really an offset
	     from the abs section */
	  r_index = 0;
	  r_extern = 0;
	}
      else
	{
	  /* Fill in symbol */
	  r_extern = 1;
	  r_index = (*g->sym_ptr_ptr)->udata.i;
	}
    }
  else
    {
      /* Just an ordinary section */
      r_extern = 0;
      r_index  = output_section->target_index;
    }

  /* now the fun stuff */
  if (bfd_header_big_endian (abfd))
    {
      natptr->r_index[0] = r_index >> 16;
      natptr->r_index[1] = r_index >> 8;
      natptr->r_index[2] = r_index;
      natptr->r_type[0] =
	(  (r_extern ?   RELOC_STD_BITS_EXTERN_BIG: 0)
	 | (r_pcrel  ?   RELOC_STD_BITS_PCREL_BIG: 0)
	 | (r_neg    ?   RELOC_STD_BITS_BASEREL_BIG: 0)
	 | (r_length <<  RELOC_STD_BITS_LENGTH_SH_BIG));
    }
  else
    {
      natptr->r_index[2] = r_index >> 16;
      natptr->r_index[1] = r_index >> 8;
      natptr->r_index[0] = r_index;
      natptr->r_type[0] =
	(  (r_extern ?   RELOC_STD_BITS_EXTERN_LITTLE: 0)
	 | (r_pcrel  ?   RELOC_STD_BITS_PCREL_LITTLE: 0)
	 | (r_neg    ?   RELOC_STD_BITS_BASEREL_LITTLE: 0)
	 | (r_length <<  RELOC_STD_BITS_LENGTH_SH_LITTLE));
    }
}

boolean
riscix_squirt_out_relocs (abfd, section)
     bfd *abfd;
     asection *section;
{
  arelent **generic;
  unsigned char *native, *natptr;
  size_t each_size;

  unsigned int count = section->reloc_count;
  size_t natsize;

  if (count == 0) return true;

  each_size = obj_reloc_entry_size (abfd);
  natsize = each_size * count;
  native = (unsigned char *) bfd_zalloc (abfd, natsize);
  if (!native)
    return false;

  generic = section->orelocation;

  for (natptr = native;
       count != 0;
       --count, natptr += each_size, ++generic)
    riscix_swap_std_reloc_out (abfd, *generic,
			       (struct reloc_std_external *) natptr);

  if ( bfd_write ((PTR) native, 1, natsize, abfd) != natsize)
    {
      bfd_release(abfd, native);
      return false;
    }

  bfd_release (abfd, native);
  return true;
}

/*
 * This is just like the standard aoutx.h version but we need to do our
 * own mapping of external reloc type values to howto entries.
 */
long
MY(canonicalize_reloc) (abfd, section, relptr, symbols)
      bfd *abfd;
      sec_ptr section;
      arelent **relptr;
      asymbol **symbols;
{
  arelent *tblptr = section->relocation;
  unsigned int count, c;
  extern reloc_howto_type NAME(aout,std_howto_table)[];

  /* If we have already read in the relocation table, return the values.  */
  if (section->flags & SEC_CONSTRUCTOR) {
    arelent_chain *chain = section->constructor_chain;

    for (count = 0; count < section->reloc_count; count++) {
      *relptr++ = &chain->relent;
      chain = chain->next;
    }
    *relptr = 0;
    return section->reloc_count;
  }
  if (tblptr && section->reloc_count) {
    for (count = 0; count++ < section->reloc_count;)
      *relptr++ = tblptr++;
    *relptr = 0;
    return section->reloc_count;
  }

  if (!NAME(aout,slurp_reloc_table) (abfd, section, symbols))
    return -1;
  tblptr = section->relocation;

  /* fix up howto entries */
  for (count = 0; count++ < section->reloc_count;)
    {
      c = tblptr->howto - NAME(aout,std_howto_table);
      BFD_ASSERT (c < RISCIX_TABLE_SIZE);
      tblptr->howto = &riscix_std_reloc_howto[c];

      *relptr++ = tblptr++;
    }
  *relptr = 0;
  return section->reloc_count;
}

/* This is the same as NAME(aout,some_aout_object_p), but has different
   expansions of the macro definitions.  */

const bfd_target *
riscix_some_aout_object_p (abfd, execp, callback_to_real_object_p)
     bfd *abfd;
     struct internal_exec *execp;
     const bfd_target *(*callback_to_real_object_p) PARAMS ((bfd *));
{
  struct aout_data_struct *rawptr, *oldrawptr;
  const bfd_target *result;

  rawptr = ((struct aout_data_struct  *)
	    bfd_zalloc (abfd, sizeof (struct aout_data_struct )));

  if (rawptr == NULL)
    return 0;

  oldrawptr = abfd->tdata.aout_data;
  abfd->tdata.aout_data = rawptr;

  /* Copy the contents of the old tdata struct.
     In particular, we want the subformat, since for hpux it was set in
     hp300hpux.c:swap_exec_header_in and will be used in
     hp300hpux.c:callback.  */
  if (oldrawptr != NULL)
    *abfd->tdata.aout_data = *oldrawptr;

  abfd->tdata.aout_data->a.hdr = &rawptr->e;
  *(abfd->tdata.aout_data->a.hdr) = *execp;     /* Copy in the internal_exec
						   struct */
  execp = abfd->tdata.aout_data->a.hdr;

  /* Set the file flags */
  abfd->flags = BFD_NO_FLAGS;
  if (execp->a_drsize || execp->a_trsize)
    abfd->flags |= HAS_RELOC;
  /* Setting of EXEC_P has been deferred to the bottom of this function */
  if (execp->a_syms)
    abfd->flags |= HAS_LINENO | HAS_DEBUG | HAS_SYMS | HAS_LOCALS;
  if (N_DYNAMIC(*execp))
    abfd->flags |= DYNAMIC;

  if ((execp->a_info & MF_SQUEEZED) != 0) /* Squeezed files aren't supported
					     (yet)! */
    {
      bfd_set_error (bfd_error_wrong_format);
      return NULL;
    }
  else if ((execp->a_info & MF_IS_SL) != 0)	/* Nor are shared libraries */
    {
      bfd_set_error (bfd_error_wrong_format);
      return NULL;
    }
  else if (N_MAGIC (*execp) == ZMAGIC)
    {
      abfd->flags |= D_PAGED | WP_TEXT;
      adata (abfd).magic = z_magic;
    }
  else if (N_MAGIC (*execp) == NMAGIC)
    {
      abfd->flags |= WP_TEXT;
      adata (abfd).magic = n_magic;
    }
  else if (N_MAGIC (*execp) == OMAGIC)
    adata (abfd).magic = o_magic;
  else
    {
      /* Should have been checked with N_BADMAG before this routine
         was called.  */
      abort ();
    }

  bfd_get_start_address (abfd) = execp->a_entry;

  obj_aout_symbols (abfd) = (aout_symbol_type *)NULL;
  bfd_get_symcount (abfd) = execp->a_syms / sizeof (struct external_nlist);

  /* The default relocation entry size is that of traditional V7 Unix.  */
  obj_reloc_entry_size (abfd) = RELOC_STD_SIZE;

  /* The default symbol entry size is that of traditional Unix.  */
  obj_symbol_entry_size (abfd) = EXTERNAL_NLIST_SIZE;

  obj_aout_external_syms (abfd) = NULL;
  obj_aout_external_strings (abfd) = NULL;
  obj_aout_sym_hashes (abfd) = NULL;

  if (! NAME(aout,make_sections) (abfd))
    return NULL;

  obj_datasec (abfd)->_raw_size = execp->a_data;
  obj_bsssec (abfd)->_raw_size = execp->a_bss;

  obj_textsec (abfd)->flags =
    (execp->a_trsize != 0
     ? (SEC_ALLOC | SEC_LOAD | SEC_CODE | SEC_HAS_CONTENTS | SEC_RELOC)
     : (SEC_ALLOC | SEC_LOAD | SEC_CODE | SEC_HAS_CONTENTS));
  obj_datasec (abfd)->flags =
    (execp->a_drsize != 0
     ? (SEC_ALLOC | SEC_LOAD | SEC_DATA | SEC_HAS_CONTENTS | SEC_RELOC)
     : (SEC_ALLOC | SEC_LOAD | SEC_DATA | SEC_HAS_CONTENTS));
  obj_bsssec (abfd)->flags = SEC_ALLOC;

  result = (*callback_to_real_object_p) (abfd);

#if defined(MACH) || defined(STAT_FOR_EXEC)
  /* The original heuristic doesn't work in some important cases. The
   * a.out file has no information about the text start address. For
   * files (like kernels) linked to non-standard addresses (ld -Ttext
   * nnn) the entry point may not be between the default text start
   * (obj_textsec(abfd)->vma) and (obj_textsec(abfd)->vma) + text size
   * This is not just a mach issue. Many kernels are loaded at non
   * standard addresses.
   */
  {
    struct stat stat_buf;
    if (abfd->iostream != NULL
	&& (abfd->flags & BFD_IN_MEMORY) == 0
        && (fstat(fileno((FILE *) (abfd->iostream)), &stat_buf) == 0)
        && ((stat_buf.st_mode & 0111) != 0))
      abfd->flags |= EXEC_P;
  }
#else /* ! MACH */
  /* Now that the segment addresses have been worked out, take a better
     guess at whether the file is executable.  If the entry point
     is within the text segment, assume it is.  (This makes files
     executable even if their entry point address is 0, as long as
     their text starts at zero.)

     At some point we should probably break down and stat the file and
     declare it executable if (one of) its 'x' bits are on...  */
  if ((execp->a_entry >= obj_textsec(abfd)->vma) &&
      (execp->a_entry < obj_textsec(abfd)->vma + obj_textsec(abfd)->_raw_size))
    abfd->flags |= EXEC_P;
#endif /* MACH */
  if (result)
    {
    }
  else
    {
      free (rawptr);
      abfd->tdata.aout_data = oldrawptr;
    }
  return result;
}

static const bfd_target *
MY(object_p) (abfd)
     bfd *abfd;
{
  struct external_exec exec_bytes;      /* Raw exec header from file */
  struct internal_exec exec;            /* Cleaned-up exec header */
  const bfd_target *target;

  if (bfd_read ((PTR) &exec_bytes, 1, EXEC_BYTES_SIZE, abfd)
      != EXEC_BYTES_SIZE) {
    if (bfd_get_error () != bfd_error_system_call)
      bfd_set_error (bfd_error_wrong_format);
    return 0;
  }

  exec.a_info = bfd_h_get_32 (abfd, exec_bytes.e_info);

  if (N_BADMAG (exec)) return 0;
#ifdef MACHTYPE_OK
  if (!(MACHTYPE_OK (N_MACHTYPE (exec)))) return 0;
#endif

  NAME(aout,swap_exec_header_in) (abfd, &exec_bytes, &exec);

  target = riscix_some_aout_object_p (abfd, &exec, MY(callback));

  return target;
}

#include "aout-target.h"