ld/emultempl/armelf.em

   1 # This shell script emits a C file. -*- C -*-
   2 #   Copyright 1991, 1993, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003,
   3 #   2004, 2005
   4 #   Free Software Foundation, Inc.
   5 #
   6 # This file is part of GLD, the Gnu Linker.
   7 #
   8 # This program is free software; you can redistribute it and/or modify
   9 # it under the terms of the GNU General Public License as published by
  10 # the Free Software Foundation; either version 2 of the License, or
  11 # (at your option) any later version.
  12 #
  13 # This program is distributed in the hope that it will be useful,
  14 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 # GNU General Public License for more details.
  17 #
  18 # You should have received a copy of the GNU General Public License
  19 # along with this program; if not, write to the Free Software
  20 # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  21 #
  22
  23 # This file is sourced from elf32.em, and defines extra arm-elf
  24 # specific routines.
  25 #
  26 test -z $TARGET2_TYPE && TARGET2_TYPE="rel"
  27 cat >>e${EMULATION_NAME}.c <<EOF
  28
  29 static char *thumb_entry_symbol = NULL;
  30 static bfd *bfd_for_interwork;
  31 static int byteswap_code = 0;
  32 static int target1_is_rel = 0${TARGET1_IS_REL};
  33 static char *target2_type = "${TARGET2_TYPE}";
  34 static int fix_v4bx = 0;
  35
  36 static void
  37 gld${EMULATION_NAME}_before_parse (void)
  38 {
  39 #ifndef TARGET_                 /* I.e., if not generic.  */
  40   ldfile_set_output_arch ("`echo ${ARCH}`", bfd_arch_unknown);
  41 #endif /* not TARGET_ */
  42   config.dynamic_link = ${DYNAMIC_LINK-TRUE};
  43   config.has_shared = `if test -n "$GENERATE_SHLIB_SCRIPT" ; then echo TRUE ; else echo FALSE ; fi`;
  44 }
  45
  46 static void
  47 arm_elf_after_open (void)
  48 {
  49   if (strstr (bfd_get_target (output_bfd), "arm") == NULL)
  50     {
  51       /* The arm backend needs special fields in the output hash structure.
  52          These will only be created if the output format is an arm format,
  53          hence we do not support linking and changing output formats at the
  54          same time.  Use a link followed by objcopy to change output formats.  */
  55       einfo ("%F%X%P: error: cannot change output format whilst linking ARM binaries\n");
  56       return;
  57     }
  58
  59   {
  60     LANG_FOR_EACH_INPUT_STATEMENT (is)
  61       {
  62         bfd_elf32_arm_add_glue_sections_to_bfd (is->the_bfd, & link_info);
  63       }
  64   }
  65
  66   /* Call the standard elf routine.  */
  67   gld${EMULATION_NAME}_after_open ();
  68 }
  69
  70 static void
  71 arm_elf_set_bfd_for_interworking (lang_statement_union_type *statement)
  72 {
  73   if (statement->header.type == lang_input_section_enum
  74       && !statement->input_section.ifile->just_syms_flag
  75       && (statement->input_section.section->flags & SEC_EXCLUDE) == 0)
  76     {
  77       asection *i = statement->input_section.section;
  78       asection *output_section = i->output_section;
  79
  80       ASSERT (output_section->owner == output_bfd);
  81
  82       /* Don't attach the interworking stubs to a dynamic object, to
  83          an empty section, etc.  */
  84       if ((output_section->flags & SEC_HAS_CONTENTS) != 0
  85           && (i->flags & SEC_NEVER_LOAD) == 0
  86           && ! (i->owner->flags & DYNAMIC)
  87           && ! i->owner->output_has_begun)
  88         {
  89           bfd_for_interwork = i->owner;
  90           bfd_for_interwork->output_has_begun = TRUE;
  91         }
  92     }
  93 }
  94
  95 static void
  96 arm_elf_before_allocation (void)
  97 {
  98   bfd *tem;
  99
 100   /* Call the standard elf routine.  */
 101   gld${EMULATION_NAME}_before_allocation ();
 102
 103   if (link_info.input_bfds != NULL)
 104     {
 105       /* The interworking bfd must be the last one in the link.  */
 106       bfd_for_interwork = NULL;
 107       for (tem = link_info.input_bfds; tem != NULL; tem = tem->link_next)
 108         tem->output_has_begun = FALSE;
 109
 110       lang_for_each_statement (arm_elf_set_bfd_for_interworking);
 111       for (tem = link_info.input_bfds; tem != NULL; tem = tem->link_next)
 112         tem->output_has_begun = FALSE;
 113
 114       /* If bfd_for_interwork is NULL, then there are no loadable sections
 115          with real contents to be linked, so we are not going to have to
 116          create any interworking stubs, so it is OK not to call
 117          bfd_elf32_arm_get_bfd_for_interworking.  */
 118       if (bfd_for_interwork != NULL)
 119         bfd_elf32_arm_get_bfd_for_interworking (bfd_for_interwork, &link_info);
 120     }
 121   /* We should be able to set the size of the interworking stub section.  */
 122
 123   /* Here we rummage through the found bfds to collect glue information.  */
 124   /* FIXME: should this be based on a command line option? krk@cygnus.com  */
 125   {
 126     LANG_FOR_EACH_INPUT_STATEMENT (is)
 127       {
 128         if (!bfd_elf32_arm_process_before_allocation (is->the_bfd, & link_info,
 129                                                       byteswap_code))
 130           {
 131             /* xgettext:c-format */
 132             einfo (_("Errors encountered processing file %s"), is->filename);
 133           }
 134       }
 135   }
 136
 137   /* We have seen it all. Allocate it, and carry on.  */
 138   bfd_elf32_arm_allocate_interworking_sections (& link_info);
 139 }
 140
 141 static void
 142 arm_elf_finish (void)
 143 {
 144   struct bfd_link_hash_entry * h;
 145
 146   /* Call the elf32.em routine.  */
 147   gld${EMULATION_NAME}_finish ();
 148
 149   if (thumb_entry_symbol == NULL)
 150     return;
 151
 152   h = bfd_link_hash_lookup (link_info.hash, thumb_entry_symbol,
 153                             FALSE, FALSE, TRUE);
 154
 155   if (h != (struct bfd_link_hash_entry *) NULL
 156       && (h->type == bfd_link_hash_defined
 157           || h->type == bfd_link_hash_defweak)
 158       && h->u.def.section->output_section != NULL)
 159     {
 160       static char buffer[32];
 161       bfd_vma val;
 162
 163       /* Special procesing is required for a Thumb entry symbol.  The
 164          bottom bit of its address must be set.  */
 165       val = (h->u.def.value
 166              + bfd_get_section_vma (output_bfd,
 167                                     h->u.def.section->output_section)
 168              + h->u.def.section->output_offset);
 169
 170       val |= 1;
 171
 172       /* Now convert this value into a string and store it in entry_symbol
 173          where the lang_finish() function will pick it up.  */
 174       buffer[0] = '0';
 175       buffer[1] = 'x';
 176
 177       sprintf_vma (buffer + 2, val);
 178
 179       if (entry_symbol.name != NULL && entry_from_cmdline)
 180         einfo (_("%P: warning: '--thumb-entry %s' is overriding '-e %s'\n"),
 181                thumb_entry_symbol, entry_symbol.name);
 182       entry_symbol.name = buffer;
 183     }
 184   else
 185     einfo (_("%P: warning: connot find thumb start symbol %s\n"),
 186            thumb_entry_symbol);
 187 }
 188
 189 /* This is a convenitent point to tell BFD about target specific flags.
 190    After the output has been created, but before inputs are read.  */
 191 static void
 192 arm_elf_create_output_section_statements (void)
 193 {
 194   bfd_elf32_arm_set_target_relocs (&link_info, target1_is_rel, target2_type,
 195                                    fix_v4bx);
 196 }
 197
 198 EOF
 199
 200 # Define some shell vars to insert bits of code into the standard elf
 201 # parse_args and list_options functions.
 202 #
 203 PARSE_AND_LIST_PROLOGUE='
 204 #define OPTION_THUMB_ENTRY              301
 205 #define OPTION_BE8                      302
 206 #define OPTION_TARGET1_REL              303
 207 #define OPTION_TARGET1_ABS              304
 208 #define OPTION_TARGET2                  305
 209 #define OPTION_FIX_V4BX                 306
 210 '
 211
 212 PARSE_AND_LIST_SHORTOPTS=p
 213
 214 PARSE_AND_LIST_LONGOPTS='
 215   { "no-pipeline-knowledge", no_argument, NULL, '\'p\''},
 216   { "thumb-entry", required_argument, NULL, OPTION_THUMB_ENTRY},
 217   { "be8", no_argument, NULL, OPTION_BE8},
 218   { "target1-rel", no_argument, NULL, OPTION_TARGET1_REL},
 219   { "target1-abs", no_argument, NULL, OPTION_TARGET1_ABS},
 220   { "target2", required_argument, NULL, OPTION_TARGET2},
 221   { "fix-v4bx", no_argument, NULL, OPTION_FIX_V4BX},
 222 '
 223
 224 PARSE_AND_LIST_OPTIONS='
 225   fprintf (file, _("     --thumb-entry=<sym>      Set the entry point to be Thumb symbol <sym>\n"));
 226   fprintf (file, _("     --be8                    Oputput BE8 format image\n"));
 227   fprintf (file, _("     --target1=rel            Interpret R_ARM_TARGET1 as R_ARM_REL32\n"));
 228   fprintf (file, _("     --target1=abs            Interpret R_ARM_TARGET1 as R_ARM_ABS32\n"));
 229   fprintf (file, _("     --target2=<type>         Specify definition of R_ARM_TARGET2\n"));
 230   fprintf (file, _("     --fix-v4bx               Rewrite BX rn as MOV pc, rn for ARMv4\n"));
 231 '
 232
 233 PARSE_AND_LIST_ARGS_CASES='
 234     case '\'p\'':
 235       /* Only here for backwards compatibility.  */
 236       break;
 237
 238     case OPTION_THUMB_ENTRY:
 239       thumb_entry_symbol = optarg;
 240       break;
 241
 242     case OPTION_BE8:
 243       byteswap_code = 1;
 244       break;
 245
 246     case OPTION_TARGET1_REL:
 247       target1_is_rel = 1;
 248       break;
 249
 250     case OPTION_TARGET1_ABS:
 251       target1_is_rel = 0;
 252       break;
 253
 254     case OPTION_TARGET2:
 255       target2_type = optarg;
 256       break;
 257
 258     case OPTION_FIX_V4BX:
 259       fix_v4bx = 1;
 260       break;
 261 '
 262
 263 # We have our own after_open and before_allocation functions, but they call
 264 # the standard routines, so give them a different name.
 265 LDEMUL_AFTER_OPEN=arm_elf_after_open
 266 LDEMUL_BEFORE_ALLOCATION=arm_elf_before_allocation
 267 LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=arm_elf_create_output_section_statements
 268
 269 # Replace the elf before_parse function with our own.
 270 LDEMUL_BEFORE_PARSE=gld"${EMULATION_NAME}"_before_parse
 271
 272 # Call the extra arm-elf function
 273 LDEMUL_FINISH=arm_elf_finish