Subversion Repositories openrisc_2011-10-31

# This shell script emits a C file. -*- C -*-
#   Copyright 2000, 2001, 2003, 2005, 2007, 2008, 2009
#   Free Software Foundation, Inc.
#   Written by Michael Sokolov <msokolov@ivan.Harhan.ORG>, based on armelf.em
#
# This file is part of the GNU Binutils.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
# MA 02110-1301, USA.


# This file is sourced from elf32.em, and defines some extra routines for m68k
# embedded systems using ELF and for some other systems using m68k ELF.  While
# it is sourced from elf32.em for all m68k ELF configurations, here we include
# only the features we want depending on the configuration.

case ${target} in
  m68*-*-elf)
    echo "#define SUPPORT_EMBEDDED_RELOCS" >>e${EMULATION_NAME}.c
    ;;
esac

case ${target} in
  *-linux*)
# Don't use multi-GOT by default due to glibc linker's assumption
# that GOT pointer points to GOT[0].
#   got_handling_target_default=GOT_HANDLING_MULTIGOT
    got_handling_target_default=GOT_HANDLING_SINGLE
    ;;
  *)
    got_handling_target_default=GOT_HANDLING_SINGLE
    ;;
esac

fragment <<EOF

#define GOT_HANDLING_SINGLE   (0)
#define GOT_HANDLING_NEGATIVE (1)
#define GOT_HANDLING_MULTIGOT (2)
#define GOT_HANDLING_TARGET_DEFAULT ${got_handling_target_default}

/* How to generate GOT.  */
static int got_handling = GOT_HANDLING_DEFAULT;

#ifdef SUPPORT_EMBEDDED_RELOCS
static void check_sections (bfd *, asection *, void *);
#endif

/* This function is run after all the input files have been opened.  */

static void
m68k_elf_after_open (void)
{
  /* Call the standard elf routine.  */
  gld${EMULATION_NAME}_after_open ();

#ifdef SUPPORT_EMBEDDED_RELOCS
  if (command_line.embedded_relocs
      && (! link_info.relocatable))
    {
      bfd *abfd;

      /* In the embedded relocs mode we create a .emreloc section for each
         input file with a nonzero .data section.  The BFD backend will fill in
         these sections with magic numbers which can be used to relocate the
         data section at run time.  */
      for (abfd = link_info.input_bfds; abfd != NULL; abfd = abfd->link_next)
        {
          asection *datasec;

          /* As first-order business, make sure that each input BFD is either
             COFF or ELF.  We need to call a special BFD backend function to
             generate the embedded relocs, and we have such functions only for
             COFF and ELF.  */
          if (bfd_get_flavour (abfd) != bfd_target_coff_flavour
              && bfd_get_flavour (abfd) != bfd_target_elf_flavour)
            einfo ("%F%B: all input objects must be COFF or ELF for --embedded-relocs\n");

          datasec = bfd_get_section_by_name (abfd, ".data");

          /* Note that we assume that the reloc_count field has already
             been set up.  We could call bfd_get_reloc_upper_bound, but
             that returns the size of a memory buffer rather than a reloc
             count.  We do not want to call bfd_canonicalize_reloc,
             because although it would always work it would force us to
             read in the relocs into BFD canonical form, which would waste
             a significant amount of time and memory.  */
          if (datasec != NULL && datasec->reloc_count > 0)
            {
              asection *relsec;

              relsec = bfd_make_section_with_flags (abfd, ".emreloc",
                                                    (SEC_ALLOC
                                                    | SEC_LOAD
                                                    | SEC_HAS_CONTENTS
                                                    | SEC_IN_MEMORY));
              if (relsec == NULL
                  || ! bfd_set_section_alignment (abfd, relsec, 2)
                  || ! bfd_set_section_size (abfd, relsec,
                                             datasec->reloc_count * 12))
                einfo ("%F%B: can not create .emreloc section: %E\n");
            }

          /* Double check that all other data sections are empty, as is
             required for embedded PIC code.  */
          bfd_map_over_sections (abfd, check_sections, datasec);
        }
    }
#endif /* SUPPORT_EMBEDDED_RELOCS */
}

#ifdef SUPPORT_EMBEDDED_RELOCS
/* Check that of the data sections, only the .data section has
   relocs.  This is called via bfd_map_over_sections.  */

static void
check_sections (bfd *abfd, asection *sec, void *datasec)
{
  if ((bfd_get_section_flags (abfd, sec) & SEC_DATA)
      && sec != datasec
      && sec->reloc_count != 0)
    einfo ("%B%X: section %s has relocs; can not use --embedded-relocs\n",
           abfd, bfd_get_section_name (abfd, sec));
}

#endif /* SUPPORT_EMBEDDED_RELOCS */

/* This function is called after the section sizes and offsets have
   been set.  */

static void
m68k_elf_after_allocation (void)
{
  /* Call the standard elf routine.  */
  gld${EMULATION_NAME}_after_allocation ();

#ifdef SUPPORT_EMBEDDED_RELOCS
  if (command_line.embedded_relocs
      && (! link_info.relocatable))
    {
      bfd *abfd;

      /* If we are generating embedded relocs, call a special BFD backend
         routine to do the work.  */
      for (abfd = link_info.input_bfds; abfd != NULL; abfd = abfd->link_next)
        {
          asection *datasec, *relsec;
          char *errmsg;

          datasec = bfd_get_section_by_name (abfd, ".data");

          if (datasec == NULL || datasec->reloc_count == 0)
            continue;

          relsec = bfd_get_section_by_name (abfd, ".emreloc");
          ASSERT (relsec != NULL);

          if (bfd_get_flavour (abfd) == bfd_target_coff_flavour)
            {
              if (! bfd_m68k_coff_create_embedded_relocs (abfd, &link_info,
                                                          datasec, relsec,
                                                          &errmsg))
                {
                  if (errmsg == NULL)
                    einfo ("%B%X: can not create runtime reloc information: %E\n",
                           abfd);
                  else
                    einfo ("%X%B: can not create runtime reloc information: %s\n",
                           abfd, errmsg);
                }
            }
          else if (bfd_get_flavour (abfd) == bfd_target_elf_flavour)
            {
              if (! bfd_m68k_elf32_create_embedded_relocs (abfd, &link_info,
                                                           datasec, relsec,
                                                           &errmsg))
                {
                  if (errmsg == NULL)
                    einfo ("%B%X: can not create runtime reloc information: %E\n",
                           abfd);
                  else
                    einfo ("%X%B: can not create runtime reloc information: %s\n",
                           abfd, errmsg);
                }
            }
          else
            abort ();
        }
    }
#endif /* SUPPORT_EMBEDDED_RELOCS */
}

/* This is a convenient point to tell BFD about target specific flags.
   After the output has been created, but before inputs are read.  */

static void
elf_m68k_create_output_section_statements (void)
{
  bfd_elf_m68k_set_target_options (&link_info, got_handling);
}

EOF

# Define some shell vars to insert bits of code into the standard elf
# parse_args and list_options functions.
#
PARSE_AND_LIST_PROLOGUE='
#define OPTION_GOT      301
'

PARSE_AND_LIST_LONGOPTS='
  { "got", required_argument, NULL, OPTION_GOT},
'

PARSE_AND_LIST_OPTIONS='
  fprintf (file, _("  --got=<type>                Specify GOT handling scheme\n"));
'

PARSE_AND_LIST_ARGS_CASES='
    case OPTION_GOT:
      if (strcmp (optarg, "target") == 0)
        got_handling = GOT_HANDLING_TARGET_DEFAULT;
      else if (strcmp (optarg, "single") == 0)
        got_handling = 0;
      else if (strcmp (optarg, "negative") == 0)
        got_handling = 1;
      else if (strcmp (optarg, "multigot") == 0)
        got_handling = 2;
      else
        einfo (_("Unrecognized --got argument '\''%s'\''.\n"), optarg);
      break;
'

# We have our own after_open and after_allocation functions, but they call
# the standard routines, so give them a different name.
LDEMUL_AFTER_OPEN=m68k_elf_after_open
LDEMUL_AFTER_ALLOCATION=m68k_elf_after_allocation
LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=elf_m68k_create_output_section_statements