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 test -z $TARGET2_TYPE && TARGET2_TYPE="rel"
  26 cat >>e${EMULATION_NAME}.c <<EOF
  27
  28 static char *thumb_entry_symbol = NULL;
  29 static bfd *bfd_for_interwork;
  30 static int byteswap_code = 0;
  31 static int target1_is_rel = 0${TARGET1_IS_REL};
  32 static char *target2_type = "${TARGET2_TYPE}";
  33 static int fix_v4bx = 0;
  34
  35 static void
  36 gld${EMULATION_NAME}_before_parse (void)
  37 {
  38 #ifndef TARGET_                 /* I.e., if not generic.  */
  39   ldfile_set_output_arch ("`echo ${ARCH}`", bfd_arch_unknown);
  40 #endif /* not TARGET_ */
  41   config.dynamic_link = ${DYNAMIC_LINK-TRUE};
  42   config.has_shared = `if test -n "$GENERATE_SHLIB_SCRIPT" ; then echo TRUE ; else echo FALSE ; fi`;
  43 }
  44
  45 static void
  46 arm_elf_after_open (void)
  47 {
  48   if (strstr (bfd_get_target (output_bfd), "arm") == NULL)
  49     {
  50       /* The arm backend needs special fields in the output hash structure.
  51          These will only be created if the output format is an arm format,
  52          hence we do not support linking and changing output formats at the
  53          same time.  Use a link followed by objcopy to change output formats.  */
  54       einfo ("%F%X%P: error: cannot change output format whilst linking ARM binaries\n");
  55       return;
  56     }
  57
  58   {
  59     LANG_FOR_EACH_INPUT_STATEMENT (is)
  60       {
  61         bfd_elf32_arm_add_glue_sections_to_bfd (is->the_bfd, & link_info);
  62       }
  63   }
  64
  65   /* Call the standard elf routine.  */
  66   gld${EMULATION_NAME}_after_open ();
  67 }
  68
  69 static void
  70 arm_elf_set_bfd_for_interworking (lang_statement_union_type *statement)
  71 {
  72   if (statement->header.type == lang_input_section_enum
  73       && !statement->input_section.ifile->just_syms_flag
  74       && (statement->input_section.section->flags & SEC_EXCLUDE) == 0)
  75     {
  76       asection *i = statement->input_section.section;
  77       asection *output_section = i->output_section;
  78
  79       ASSERT (output_section->owner == output_bfd);
  80
  81       /* Don't attach the interworking stubs to a dynamic object, to
  82          an empty section, etc.  */
  83       if ((output_section->flags & SEC_HAS_CONTENTS) != 0
  84           && (i->flags & SEC_NEVER_LOAD) == 0
  85           && ! (i->owner->flags & DYNAMIC)
  86           && ! i->owner->output_has_begun)
  87         {
  88           bfd_for_interwork = i->owner;
  89           bfd_for_interwork->output_has_begun = TRUE;
  90         }
  91     }
  92 }
  93
  94 static void
  95 arm_elf_before_allocation (void)
  96 {
  97   bfd *tem;
  98
  99   /* Call the standard elf routine.  */
 100   gld${EMULATION_NAME}_before_allocation ();
 101
 102   if (link_info.input_bfds != NULL)
 103     {
 104       /* The interworking bfd must be the last one in the link.  */
 105       bfd_for_interwork = NULL;
 106       for (tem = link_info.input_bfds; tem != NULL; tem = tem->link_next)
 107         tem->output_has_begun = FALSE;
 108
 109       lang_for_each_statement (arm_elf_set_bfd_for_interworking);
 110       for (tem = link_info.input_bfds; tem != NULL; tem = tem->link_next)
 111         tem->output_has_begun = FALSE;
 112
 113       /* If bfd_for_interwork is NULL, then there are no loadable sections
 114          with real contents to be linked, so we are not going to have to
 115          create any interworking stubs, so it is OK not to call
 116          bfd_elf32_arm_get_bfd_for_interworking.  */
 117       if (bfd_for_interwork != NULL)
 118         bfd_elf32_arm_get_bfd_for_interworking (bfd_for_interwork, &link_info);
 119     }
 120   /* We should be able to set the size of the interworking stub section.  */
 121
 122   /* Here we rummage through the found bfds to collect glue information.  */
 123   /* FIXME: should this be based on a command line option? krk@cygnus.com  */
 124   {
 125     LANG_FOR_EACH_INPUT_STATEMENT (is)
 126       {
 127         if (!bfd_elf32_arm_process_before_allocation (is->the_bfd, & link_info,
 128                                                       byteswap_code))
 129           {
 130             /* xgettext:c-format */
 131             einfo (_("Errors encountered processing file %s"), is->filename);
 132           }
 133       }
 134   }
 135
 136   /* We have seen it all. Allocate it, and carry on.  */
 137   bfd_elf32_arm_allocate_interworking_sections (& link_info);
 138 }
 139
 140 static void
 141 arm_elf_finish (void)
 142 {
 143   struct bfd_link_hash_entry * h;
 144
 145   /* Call the elf32.em routine.  */
 146   gld${EMULATION_NAME}_finish ();
 147
 148   if (thumb_entry_symbol == NULL)
 149     return;
 150
 151   h = bfd_link_hash_lookup (link_info.hash, thumb_entry_symbol,
 152                             FALSE, FALSE, TRUE);
 153
 154   if (h != (struct bfd_link_hash_entry *) NULL
 155       && (h->type == bfd_link_hash_defined
 156           || h->type == bfd_link_hash_defweak)
 157       && h->u.def.section->output_section != NULL)
 158     {
 159       static char buffer[32];
 160       bfd_vma val;
 161
 162       /* Special procesing is required for a Thumb entry symbol.  The
 163          bottom bit of its address must be set.  */
 164       val = (h->u.def.value
 165              + bfd_get_section_vma (output_bfd,
 166                                     h->u.def.section->output_section)
 167              + h->u.def.section->output_offset);
 168
 169       val |= 1;
 170
 171       /* Now convert this value into a string and store it in entry_symbol
 172          where the lang_finish() function will pick it up.  */
 173       buffer[0] = '0';
 174       buffer[1] = 'x';
 175
 176       sprintf_vma (buffer + 2, val);
 177
 178       if (entry_symbol.name != NULL && entry_from_cmdline)
 179         einfo (_("%P: warning: '--thumb-entry %s' is overriding '-e %s'\n"),
 180                thumb_entry_symbol, entry_symbol.name);
 181       entry_symbol.name = buffer;
 182     }
 183   else
 184     einfo (_("%P: warning: connot find thumb start symbol %s\n"),
 185            thumb_entry_symbol);
 186 }
 187
 188 /* This is a convenitent point to tell BFD about target specific flags.
 189    After the output has been created, but before inputs are read.  */
 190 static void
 191 arm_elf_create_output_section_statements (void)
 192 {
 193   bfd_elf32_arm_set_target_relocs (&link_info, target1_is_rel, target2_type,
 194                                    fix_v4bx);
 195 }
 196
 197 EOF
 198
 199 # Define some shell vars to insert bits of code into the standard elf
 200 # parse_args and list_options functions.
 201 #
 202 PARSE_AND_LIST_PROLOGUE='
 203 #define OPTION_THUMB_ENTRY              301
 204 #define OPTION_BE8                      302
 205 #define OPTION_TARGET1_REL              303
 206 #define OPTION_TARGET1_ABS              304
 207 #define OPTION_TARGET2                  305
 208 #define OPTION_FIX_V4BX                 306
 209 '
 210
 211 PARSE_AND_LIST_SHORTOPTS=p
 212
 213 PARSE_AND_LIST_LONGOPTS='
 214   { "no-pipeline-knowledge", no_argument, NULL, '\'p\''},
 215   { "thumb-entry", required_argument, NULL, OPTION_THUMB_ENTRY},
 216   { "be8", no_argument, NULL, OPTION_BE8},
 217   { "target1-rel", no_argument, NULL, OPTION_TARGET1_REL},
 218   { "target1-abs", no_argument, NULL, OPTION_TARGET1_ABS},
 219   { "target2", required_argument, NULL, OPTION_TARGET2},
 220   { "fix-v4bx", no_argument, NULL, OPTION_FIX_V4BX},
 221 '
 222
 223 PARSE_AND_LIST_OPTIONS='
 224   fprintf (file, _("     --thumb-entry=<sym>      Set the entry point to be Thumb symbol <sym>\n"));
 225   fprintf (file, _("     --be8                    Oputput BE8 format image\n"));
 226   fprintf (file, _("     --target1=rel            Interpret R_ARM_TARGET1 as R_ARM_REL32\n"));
 227   fprintf (file, _("     --target1=abs            Interpret R_ARM_TARGET1 as R_ARM_ABS32\n"));
 228   fprintf (file, _("     --target2=<type>         Specify definition of R_ARM_TARGET2\n"));
 229   fprintf (file, _("     --fix-v4bx               Rewrite BX rn as MOV pc, rn for ARMv4\n"));
 230 '
 231
 232 PARSE_AND_LIST_ARGS_CASES='
 233     case '\'p\'':
 234       /* Only here for backwards compatibility.  */
 235       break;
 236
 237     case OPTION_THUMB_ENTRY:
 238       thumb_entry_symbol = optarg;
 239       break;
 240
 241     case OPTION_BE8:
 242       byteswap_code = 1;
 243       break;
 244
 245     case OPTION_TARGET1_REL:
 246       target1_is_rel = 1;
 247       break;
 248
 249     case OPTION_TARGET1_ABS:
 250       target1_is_rel = 0;
 251       break;
 252
 253     case OPTION_TARGET2:
 254       target2_type = optarg;
 255       break;
 256
 257     case OPTION_FIX_V4BX:
 258       fix_v4bx = 1;
 259       break;
 260 '
 261
 262 # We have our own after_open and before_allocation functions, but they call
 263 # the standard routines, so give them a different name.
 264 LDEMUL_AFTER_OPEN=arm_elf_after_open
 265 LDEMUL_BEFORE_ALLOCATION=arm_elf_before_allocation
 266 LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=arm_elf_create_output_section_statements
 267
 268 # Replace the elf before_parse function with our own.
 269 LDEMUL_BEFORE_PARSE=gld"${EMULATION_NAME}"_before_parse
 270
 271 # Call the extra arm-elf function
 272 LDEMUL_FINISH=arm_elf_finish