ld/emultempl/m68kelf.em

   1 # This shell script emits a C file. -*- C -*-
   2 #   Copyright 2000, 2001, 2003 Free Software Foundation, Inc.
   3 #   Written by Michael Sokolov <msokolov@ivan.Harhan.ORG>, based on armelf.em
   4 #
   5 # This file is part of GLD, the Gnu Linker.
   6 #
   7 # This program is free software; you can redistribute it and/or modify
   8 # it under the terms of the GNU General Public License as published by
   9 # the Free Software Foundation; either version 2 of the License, or
  10 # (at your option) any later version.
  11 #
  12 # This program is distributed in the hope that it will be useful,
  13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 # GNU General Public License for more details.
  16 #
  17 # You should have received a copy of the GNU General Public License
  18 # along with this program; if not, write to the Free Software
  19 # Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.
  20
  21 # This file is sourced from elf32.em, and defines some extra routines for m68k
  22 # embedded systems using ELF and for some other systems using m68k ELF.  While
  23 # it is sourced from elf32.em for all m68k ELF configurations, here we include
  24 # only the features we want depending on the configuration.
  25
  26 case ${target} in
  27   m68*-*-elf)
  28     echo "#define SUPPORT_EMBEDDED_RELOCS" >>e${EMULATION_NAME}.c
  29     ;;
  30 esac
  31
  32 cat >>e${EMULATION_NAME}.c <<EOF
  33
  34 #ifdef SUPPORT_EMBEDDED_RELOCS
  35 static void check_sections (bfd *, asection *, void *);
  36 #endif
  37
  38 /* This function is run after all the input files have been opened.  */
  39
  40 static void
  41 m68k_elf_after_open (void)
  42 {
  43   /* Call the standard elf routine.  */
  44   gld${EMULATION_NAME}_after_open ();
  45
  46 #ifdef SUPPORT_EMBEDDED_RELOCS
  47   if (command_line.embedded_relocs
  48       && (! link_info.relocatable))
  49     {
  50       bfd *abfd;
  51
  52       /* In the embedded relocs mode we create a .emreloc section for each
  53          input file with a nonzero .data section.  The BFD backend will fill in
  54          these sections with magic numbers which can be used to relocate the
  55          data section at run time.  */
  56       for (abfd = link_info.input_bfds; abfd != NULL; abfd = abfd->link_next)
  57         {
  58           asection *datasec;
  59
  60           /* As first-order business, make sure that each input BFD is either
  61              COFF or ELF.  We need to call a special BFD backend function to
  62              generate the embedded relocs, and we have such functions only for
  63              COFF and ELF.  */
  64           if (bfd_get_flavour (abfd) != bfd_target_coff_flavour
  65               && bfd_get_flavour (abfd) != bfd_target_elf_flavour)
  66             einfo ("%F%B: all input objects must be COFF or ELF for --embedded-relocs\n");
  67
  68           datasec = bfd_get_section_by_name (abfd, ".data");
  69
  70           /* Note that we assume that the reloc_count field has already
  71              been set up.  We could call bfd_get_reloc_upper_bound, but
  72              that returns the size of a memory buffer rather than a reloc
  73              count.  We do not want to call bfd_canonicalize_reloc,
  74              because although it would always work it would force us to
  75              read in the relocs into BFD canonical form, which would waste
  76              a significant amount of time and memory.  */
  77           if (datasec != NULL && datasec->reloc_count > 0)
  78             {
  79               asection *relsec;
  80
  81               relsec = bfd_make_section (abfd, ".emreloc");
  82               if (relsec == NULL
  83                   || ! bfd_set_section_flags (abfd, relsec,
  84                                               (SEC_ALLOC
  85                                                | SEC_LOAD
  86                                                | SEC_HAS_CONTENTS
  87                                                | SEC_IN_MEMORY))
  88                   || ! bfd_set_section_alignment (abfd, relsec, 2)
  89                   || ! bfd_set_section_size (abfd, relsec,
  90                                              datasec->reloc_count * 12))
  91                 einfo ("%F%B: can not create .emreloc section: %E\n");
  92             }
  93
  94           /* Double check that all other data sections are empty, as is
  95              required for embedded PIC code.  */
  96           bfd_map_over_sections (abfd, check_sections, datasec);
  97         }
  98     }
  99 #endif /* SUPPORT_EMBEDDED_RELOCS */
 100 }
 101
 102 #ifdef SUPPORT_EMBEDDED_RELOCS
 103 /* Check that of the data sections, only the .data section has
 104    relocs.  This is called via bfd_map_over_sections.  */
 105
 106 static void
 107 check_sections (bfd *abfd, asection *sec, void *datasec)
 108 {
 109   if ((bfd_get_section_flags (abfd, sec) & SEC_DATA)
 110       && sec != datasec
 111       && sec->reloc_count != 0)
 112     einfo ("%B%X: section %s has relocs; can not use --embedded-relocs\n",
 113            abfd, bfd_get_section_name (abfd, sec));
 114 }
 115
 116 #endif /* SUPPORT_EMBEDDED_RELOCS */
 117
 118 /* This function is called after the section sizes and offsets have
 119    been set.  */
 120
 121 static void
 122 m68k_elf_after_allocation (void)
 123 {
 124   /* Call the standard elf routine.  */
 125   after_allocation_default ();
 126
 127 #ifdef SUPPORT_EMBEDDED_RELOCS
 128   if (command_line.embedded_relocs
 129       && (! link_info.relocatable))
 130     {
 131       bfd *abfd;
 132
 133       /* If we are generating embedded relocs, call a special BFD backend
 134          routine to do the work.  */
 135       for (abfd = link_info.input_bfds; abfd != NULL; abfd = abfd->link_next)
 136         {
 137           asection *datasec, *relsec;
 138           char *errmsg;
 139
 140           datasec = bfd_get_section_by_name (abfd, ".data");
 141
 142           if (datasec == NULL || datasec->reloc_count == 0)
 143             continue;
 144
 145           relsec = bfd_get_section_by_name (abfd, ".emreloc");
 146           ASSERT (relsec != NULL);
 147
 148           if (bfd_get_flavour (abfd) == bfd_target_coff_flavour)
 149             {
 150               if (! bfd_m68k_coff_create_embedded_relocs (abfd, &link_info,
 151                                                           datasec, relsec,
 152                                                           &errmsg))
 153                 {
 154                   if (errmsg == NULL)
 155                     einfo ("%B%X: can not create runtime reloc information: %E\n",
 156                            abfd);
 157                   else
 158                     einfo ("%X%B: can not create runtime reloc information: %s\n",
 159                            abfd, errmsg);
 160                 }
 161             }
 162           else if (bfd_get_flavour (abfd) == bfd_target_elf_flavour)
 163             {
 164               if (! bfd_m68k_elf32_create_embedded_relocs (abfd, &link_info,
 165                                                            datasec, relsec,
 166                                                            &errmsg))
 167                 {
 168                   if (errmsg == NULL)
 169                     einfo ("%B%X: can not create runtime reloc information: %E\n",
 170                            abfd);
 171                   else
 172                     einfo ("%X%B: can not create runtime reloc information: %s\n",
 173                            abfd, errmsg);
 174                 }
 175             }
 176           else
 177             abort ();
 178         }
 179     }
 180 #endif /* SUPPORT_EMBEDDED_RELOCS */
 181 }
 182
 183 EOF
 184
 185 # We have our own after_open and after_allocation functions, but they call
 186 # the standard routines, so give them a different name.
 187 LDEMUL_AFTER_OPEN=m68k_elf_after_open
 188 LDEMUL_AFTER_ALLOCATION=m68k_elf_after_allocation