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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, 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${EMULATION_NAME}.c <<EOF
  33
  34 static void m68k_elf_after_open PARAMS ((void));
  35 #ifdef SUPPORT_EMBEDDED_RELOCS
  36 static void check_sections PARAMS ((bfd *, asection *, PTR));
  37 #endif
  38 static void m68k_elf_after_allocation PARAMS ((void));
  39
  40 /* This function is run after all the input files have been opened.  */
  41
  42 static void
  43 m68k_elf_after_open ()
  44 {
  45   /* Call the standard elf routine.  */
  46   gld${EMULATION_NAME}_after_open ();
  47
  48 #ifdef SUPPORT_EMBEDDED_RELOCS
  49   if (command_line.embedded_relocs
  50       && (! link_info.relocatable))
  51     {
  52       bfd *abfd;
  53
  54       /* In the embedded relocs mode we create a .emreloc section for each
  55          input file with a nonzero .data section.  The BFD backend will fill in
  56          these sections with magic numbers which can be used to relocate the
  57          data section at run time.  */
  58       for (abfd = link_info.input_bfds; abfd != NULL; abfd = abfd->link_next)
  59         {
  60           asection *datasec;
  61
  62           /* As first-order business, make sure that each input BFD is either
  63              COFF or ELF.  We need to call a special BFD backend function to
  64              generate the embedded relocs, and we have such functions only for
  65              COFF and ELF.  */
  66           if (bfd_get_flavour (abfd) != bfd_target_coff_flavour
  67               && bfd_get_flavour (abfd) != bfd_target_elf_flavour)
  68             einfo ("%F%B: all input objects must be COFF or ELF for --embedded-relocs\n");
  69
  70           datasec = bfd_get_section_by_name (abfd, ".data");
  71
  72           /* Note that we assume that the reloc_count field has already
  73              been set up.  We could call bfd_get_reloc_upper_bound, but
  74              that returns the size of a memory buffer rather than a reloc
  75              count.  We do not want to call bfd_canonicalize_reloc,
  76              because although it would always work it would force us to
  77              read in the relocs into BFD canonical form, which would waste
  78              a significant amount of time and memory.  */
  79           if (datasec != NULL && datasec->reloc_count > 0)
  80             {
  81               asection *relsec;
  82
  83               relsec = bfd_make_section (abfd, ".emreloc");
  84               if (relsec == NULL
  85                   || ! bfd_set_section_flags (abfd, relsec,
  86                                               (SEC_ALLOC
  87                                                | SEC_LOAD
  88                                                | SEC_HAS_CONTENTS
  89                                                | SEC_IN_MEMORY))
  90                   || ! bfd_set_section_alignment (abfd, relsec, 2)
  91                   || ! bfd_set_section_size (abfd, relsec,
  92                                              datasec->reloc_count * 12))
  93                 einfo ("%F%B: can not create .emreloc section: %E\n");
  94             }
  95
  96           /* Double check that all other data sections are empty, as is
  97              required for embedded PIC code.  */
  98           bfd_map_over_sections (abfd, check_sections, (PTR) datasec);
  99         }
 100     }
 101 #endif /* SUPPORT_EMBEDDED_RELOCS */
 102 }
 103
 104 #ifdef SUPPORT_EMBEDDED_RELOCS
 105 /* Check that of the data sections, only the .data section has
 106    relocs.  This is called via bfd_map_over_sections.  */
 107
 108 static void
 109 check_sections (abfd, sec, datasec)
 110      bfd *abfd;
 111      asection *sec;
 112      PTR datasec;
 113 {
 114   if ((bfd_get_section_flags (abfd, sec) & SEC_DATA)
 115       && sec != (asection *) datasec
 116       && sec->reloc_count != 0)
 117     einfo ("%B%X: section %s has relocs; can not use --embedded-relocs\n",
 118            abfd, bfd_get_section_name (abfd, sec));
 119 }
 120
 121 #endif /* SUPPORT_EMBEDDED_RELOCS */
 122
 123 /* This function is called after the section sizes and offsets have
 124    been set.  */
 125
 126 static void
 127 m68k_elf_after_allocation ()
 128 {
 129   /* Call the standard elf routine.  */
 130   after_allocation_default ();
 131
 132 #ifdef SUPPORT_EMBEDDED_RELOCS
 133   if (command_line.embedded_relocs
 134       && (! link_info.relocatable))
 135     {
 136       bfd *abfd;
 137
 138       /* If we are generating embedded relocs, call a special BFD backend
 139          routine to do the work.  */
 140       for (abfd = link_info.input_bfds; abfd != NULL; abfd = abfd->link_next)
 141         {
 142           asection *datasec, *relsec;
 143           char *errmsg;
 144
 145           datasec = bfd_get_section_by_name (abfd, ".data");
 146
 147           if (datasec == NULL || datasec->reloc_count == 0)
 148             continue;
 149
 150           relsec = bfd_get_section_by_name (abfd, ".emreloc");
 151           ASSERT (relsec != NULL);
 152
 153           if (bfd_get_flavour (abfd) == bfd_target_coff_flavour)
 154             {
 155               if (! bfd_m68k_coff_create_embedded_relocs (abfd, &link_info,
 156                                                           datasec, relsec,
 157                                                           &errmsg))
 158                 {
 159                   if (errmsg == NULL)
 160                     einfo ("%B%X: can not create runtime reloc information: %E\n",
 161                            abfd);
 162                   else
 163                     einfo ("%X%B: can not create runtime reloc information: %s\n",
 164                            abfd, errmsg);
 165                 }
 166             }
 167           else if (bfd_get_flavour (abfd) == bfd_target_elf_flavour)
 168             {
 169               if (! bfd_m68k_elf32_create_embedded_relocs (abfd, &link_info,
 170                                                            datasec, relsec,
 171                                                            &errmsg))
 172                 {
 173                   if (errmsg == NULL)
 174                     einfo ("%B%X: can not create runtime reloc information: %E\n",
 175                            abfd);
 176                   else
 177                     einfo ("%X%B: can not create runtime reloc information: %s\n",
 178                            abfd, errmsg);
 179                 }
 180             }
 181           else
 182             abort ();
 183         }
 184     }
 185 #endif /* SUPPORT_EMBEDDED_RELOCS */
 186 }
 187
 188 EOF
 189
 190 # We have our own after_open and after_allocation functions, but they call
 191 # the standard routines, so give them a different name.
 192 LDEMUL_AFTER_OPEN=m68k_elf_after_open
 193 LDEMUL_AFTER_ALLOCATION=m68k_elf_after_allocation