ld/emultempl/armelf.em

   1 # This shell script emits a C file. -*- C -*-
   2 #   Copyright 1991, 1993, 1996, 1997, 1998, 1999, 2000, 2002, 2003, 2004
   3 #   Free Software Foundation, Inc.
   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
  22 # This file is sourced from elf32.em, and defines extra arm-elf
  23 # specific routines.
  24 #
  25 cat >>e${EMULATION_NAME}.c <<EOF
  26
  27 static int no_pipeline_knowledge = 0;
  28 static char *thumb_entry_symbol = NULL;
  29 static bfd *bfd_for_interwork;
  30
  31 static void
  32 gld${EMULATION_NAME}_before_parse (void)
  33 {
  34 #ifndef TARGET_                 /* I.e., if not generic.  */
  35   ldfile_set_output_arch ("`echo ${ARCH}`", bfd_arch_unknown);
  36 #endif /* not TARGET_ */
  37   config.dynamic_link = ${DYNAMIC_LINK-TRUE};
  38   config.has_shared = `if test -n "$GENERATE_SHLIB_SCRIPT" ; then echo TRUE ; else echo FALSE ; fi`;
  39 }
  40
  41 static void
  42 arm_elf_after_open (void)
  43 {
  44   if (strstr (bfd_get_target (output_bfd), "arm") == NULL)
  45     {
  46       /* The arm backend needs special fields in the output hash structure.
  47          These will only be created if the output format is an arm format,
  48          hence we do not support linking and changing output formats at the
  49          same time.  Use a link followed by objcopy to change output formats.  */
  50       einfo ("%F%X%P: error: cannot change output format whilst linking ARM binaries\n");
  51       return;
  52     }
  53
  54   {
  55     LANG_FOR_EACH_INPUT_STATEMENT (is)
  56       {
  57         bfd_elf32_arm_add_glue_sections_to_bfd (is->the_bfd, & link_info);
  58       }
  59   }
  60
  61   /* Call the standard elf routine.  */
  62   gld${EMULATION_NAME}_after_open ();
  63 }
  64
  65 static void
  66 arm_elf_set_bfd_for_interworking (lang_statement_union_type *statement)
  67 {
  68   if (statement->header.type == lang_input_section_enum
  69       && !statement->input_section.ifile->just_syms_flag)
  70     {
  71       asection *i = statement->input_section.section;
  72       asection *output_section = i->output_section;
  73
  74       ASSERT (output_section->owner == output_bfd);
  75
  76       if ((output_section->flags & SEC_HAS_CONTENTS) != 0
  77           && (i->flags & SEC_NEVER_LOAD) == 0
  78           && ! i->owner->output_has_begun)
  79         {
  80           bfd_for_interwork = i->owner;
  81           bfd_for_interwork->output_has_begun = TRUE;
  82         }
  83     }
  84 }
  85
  86 static void
  87 arm_elf_before_allocation (void)
  88 {
  89   bfd *tem;
  90
  91   /* Call the standard elf routine.  */
  92   gld${EMULATION_NAME}_before_allocation ();
  93
  94   if (link_info.input_bfds != NULL)
  95     {
  96       /* The interworking bfd must be the last one in the link.  */
  97       bfd_for_interwork = NULL;
  98       for (tem = link_info.input_bfds; tem != NULL; tem = tem->link_next)
  99         tem->output_has_begun = FALSE;
 100
 101       lang_for_each_statement (arm_elf_set_bfd_for_interworking);
 102       for (tem = link_info.input_bfds; tem != NULL; tem = tem->link_next)
 103         tem->output_has_begun = FALSE;
 104
 105       /* If bfd_for_interwork is NULL, then there are no loadable sections
 106          with real contents to be linked, so we are not going to have to
 107          create any interworking stubs, so it is OK not to call
 108          bfd_elf32_arm_get_bfd_for_interworking.  */
 109       if (bfd_for_interwork != NULL)
 110         bfd_elf32_arm_get_bfd_for_interworking (bfd_for_interwork, &link_info);
 111     }
 112   /* We should be able to set the size of the interworking stub section.  */
 113
 114   /* Here we rummage through the found bfds to collect glue information.  */
 115   /* FIXME: should this be based on a command line option? krk@cygnus.com  */
 116   {
 117     LANG_FOR_EACH_INPUT_STATEMENT (is)
 118       {
 119         if (!bfd_elf32_arm_process_before_allocation (is->the_bfd, & link_info,
 120                                                       no_pipeline_knowledge))
 121           {
 122             /* xgettext:c-format */
 123             einfo (_("Errors encountered processing file %s"), is->filename);
 124           }
 125       }
 126   }
 127
 128   /* We have seen it all. Allocate it, and carry on.  */
 129   bfd_elf32_arm_allocate_interworking_sections (& link_info);
 130 }
 131
 132 static void
 133 arm_elf_finish (void)
 134 {
 135   struct bfd_link_hash_entry * h;
 136
 137   /* Call the elf32.em routine.  */
 138   gld${EMULATION_NAME}_finish ();
 139
 140   if (thumb_entry_symbol == NULL)
 141     return;
 142
 143   h = bfd_link_hash_lookup (link_info.hash, thumb_entry_symbol,
 144                             FALSE, FALSE, TRUE);
 145
 146   if (h != (struct bfd_link_hash_entry *) NULL
 147       && (h->type == bfd_link_hash_defined
 148           || h->type == bfd_link_hash_defweak)
 149       && h->u.def.section->output_section != NULL)
 150     {
 151       static char buffer[32];
 152       bfd_vma val;
 153
 154       /* Special procesing is required for a Thumb entry symbol.  The
 155          bottom bit of its address must be set.  */
 156       val = (h->u.def.value
 157              + bfd_get_section_vma (output_bfd,
 158                                     h->u.def.section->output_section)
 159              + h->u.def.section->output_offset);
 160
 161       val |= 1;
 162
 163       /* Now convert this value into a string and store it in entry_symbol
 164          where the lang_finish() function will pick it up.  */
 165       buffer[0] = '0';
 166       buffer[1] = 'x';
 167
 168       sprintf_vma (buffer + 2, val);
 169
 170       if (entry_symbol.name != NULL && entry_from_cmdline)
 171         einfo (_("%P: warning: '--thumb-entry %s' is overriding '-e %s'\n"),
 172                thumb_entry_symbol, entry_symbol.name);
 173       entry_symbol.name = buffer;
 174     }
 175   else
 176     einfo (_("%P: warning: connot find thumb start symbol %s\n"),
 177            thumb_entry_symbol);
 178 }
 179
 180 EOF
 181
 182 # Define some shell vars to insert bits of code into the standard elf
 183 # parse_args and list_options functions.
 184 #
 185 PARSE_AND_LIST_PROLOGUE='
 186 #define OPTION_THUMB_ENTRY              301
 187 '
 188
 189 PARSE_AND_LIST_SHORTOPTS=p
 190
 191 PARSE_AND_LIST_LONGOPTS='
 192   { "no-pipeline-knowledge", no_argument, NULL, '\'p\''},
 193   { "thumb-entry", required_argument, NULL, OPTION_THUMB_ENTRY},
 194 '
 195
 196 PARSE_AND_LIST_OPTIONS='
 197   fprintf (file, _("  -p --no-pipeline-knowledge  Stop the linker knowing about the pipeline length\n"));
 198   fprintf (file, _("     --thumb-entry=<sym>      Set the entry point to be Thumb symbol <sym>\n"));
 199 '
 200
 201 PARSE_AND_LIST_ARGS_CASES='
 202     case '\'p\'':
 203       no_pipeline_knowledge = 1;
 204       break;
 205
 206     case OPTION_THUMB_ENTRY:
 207       thumb_entry_symbol = optarg;
 208       break;
 209 '
 210
 211 # We have our own after_open and before_allocation functions, but they call
 212 # the standard routines, so give them a different name.
 213 LDEMUL_AFTER_OPEN=arm_elf_after_open
 214 LDEMUL_BEFORE_ALLOCATION=arm_elf_before_allocation
 215
 216 # Replace the elf before_parse function with our own.
 217 LDEMUL_BEFORE_PARSE=gld"${EMULATION_NAME}"_before_parse
 218
 219 # Call the extra arm-elf function
 220 LDEMUL_FINISH=arm_elf_finish