ld/emultempl/armelf.em

   1 # This shell script emits a C file. -*- C -*-
   2 #   Copyright 1991, 1993, 1996, 1997, 1998, 1999, 2000, 2002
   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${EMULATION_NAME}.c <<EOF
  26
  27 #include "elf-bfd.h"
  28 #include "elf/arm.h"
  29
  30 static int    no_pipeline_knowledge = 0;
  31 static char * thumb_entry_symbol = NULL;
  32 static bfd *  bfd_for_interwork;
  33
  34 static void  arm_elf_after_open                PARAMS ((void));
  35 static void  arm_elf_set_bfd_for_interworking  PARAMS ((lang_statement_union_type *));
  36 static void  arm_elf_before_allocation         PARAMS ((void));
  37 static void  arm_elf_stringify_thumb_address   PARAMS ((struct bfd_link_hash_entry *, char *));
  38 static void  arm_elf_finish                    PARAMS ((void));
  39
  40
  41 static void
  42 gld${EMULATION_NAME}_before_parse ()
  43 {
  44 #ifndef TARGET_                 /* I.e., if not generic.  */
  45   ldfile_set_output_arch ("`echo ${ARCH}`");
  46 #endif /* not TARGET_ */
  47   config.dynamic_link = ${DYNAMIC_LINK-true};
  48   config.has_shared = `if test -n "$GENERATE_SHLIB_SCRIPT" ; then echo true ; else echo false ; fi`;
  49 }
  50
  51 static void
  52 arm_elf_after_open ()
  53 {
  54   if (strstr (bfd_get_target (output_bfd), "arm") == NULL)
  55     {
  56       /* The arm backend needs special fields in the output hash structure.
  57          These will only be created if the output format is an arm format,
  58          hence we do not support linking and changing output formats at the
  59          same time.  Use a link followed by objcopy to change output formats.  */
  60       einfo ("%F%X%P: error: cannot change output format whilst linking ARM binaries\n");
  61       return;
  62     }
  63
  64   {
  65     LANG_FOR_EACH_INPUT_STATEMENT (is)
  66       {
  67         bfd_elf32_arm_add_glue_sections_to_bfd (is->the_bfd, & link_info);
  68       }
  69   }
  70
  71   /* Call the standard elf routine.  */
  72   gld${EMULATION_NAME}_after_open ();
  73 }
  74
  75 static void
  76 arm_elf_set_bfd_for_interworking (statement)
  77      lang_statement_union_type * statement;
  78 {
  79   if (statement->header.type == lang_input_section_enum
  80       && statement->input_section.ifile->just_syms_flag == false)
  81     {
  82       asection * i = statement->input_section.section;
  83       asection * output_section = i->output_section;
  84
  85       ASSERT (output_section->owner == output_bfd);
  86
  87       if ((output_section->flags & SEC_HAS_CONTENTS) != 0
  88           && (i->flags & SEC_NEVER_LOAD) == 0
  89           && ! i->owner->output_has_begun)
  90         {
  91           bfd_for_interwork = i->owner;
  92           bfd_for_interwork->output_has_begun = true;
  93         }
  94     }
  95 }
  96
  97 static void
  98 arm_elf_before_allocation ()
  99 {
 100   bfd * tem;
 101
 102   /* Call the standard elf routine.  */
 103   gld${EMULATION_NAME}_before_allocation ();
 104
 105   if (link_info.input_bfds != NULL)
 106     {
 107       /* The interworking bfd must be the last one in the link.  */
 108       bfd_for_interwork = NULL;
 109       for (tem = link_info.input_bfds; tem != NULL; tem = tem->link_next)
 110         tem->output_has_begun = false;
 111
 112       lang_for_each_statement (arm_elf_set_bfd_for_interworking);
 113       ASSERT (bfd_for_interwork != NULL);
 114       for (tem = link_info.input_bfds; tem != NULL; tem = tem->link_next)
 115         tem->output_has_begun = false;
 116
 117       bfd_elf32_arm_get_bfd_for_interworking (bfd_for_interwork, &link_info);
 118     }
 119   /* We should be able to set the size of the interworking stub section.  */
 120
 121   /* Here we rummage through the found bfds to collect glue information.  */
 122   /* FIXME: should this be based on a command line option? krk@cygnus.com  */
 123   {
 124     LANG_FOR_EACH_INPUT_STATEMENT (is)
 125       {
 126         if (!bfd_elf32_arm_process_before_allocation (is->the_bfd, & link_info,
 127                                                       no_pipeline_knowledge))
 128           {
 129             /* xgettext:c-format */
 130             einfo (_("Errors encountered processing file %s"), is->filename);
 131           }
 132       }
 133   }
 134
 135   /* We have seen it all. Allocate it, and carry on.  */
 136   bfd_elf32_arm_allocate_interworking_sections (& link_info);
 137 }
 138
 139 void
 140 arm_elf_stringify_thumb_address (h, buffer)
 141      struct bfd_link_hash_entry * h;
 142      char * buffer;
 143 {
 144   bfd_vma val;
 145
 146   /* Get the address of the symbol.  */
 147   val = (h->u.def.value
 148          + bfd_get_section_vma (output_bfd,
 149                                 h->u.def.section->output_section)
 150          + h->u.def.section->output_offset);
 151   /* This is a thumb address, so the bottom bit of its address must be set.  */
 152   val |= 1;
 153
 154   /* Now convert this value into a string.  */
 155   buffer[0] = '0';
 156   buffer[1] = 'x';
 157
 158   sprintf_vma (buffer + 2, val);
 159 }
 160
 161 static void
 162 arm_elf_finish ()
 163 {
 164   struct bfd_link_hash_entry * h;
 165
 166   /* Call the elf32.em routine.  */
 167   gld${EMULATION_NAME}_finish ();
 168
 169   if (thumb_entry_symbol != NULL)
 170     {
 171       static char buffer[32];
 172
 173       h = bfd_link_hash_lookup (link_info.hash, thumb_entry_symbol,
 174                                 false, false, true);
 175
 176       if (h != (struct bfd_link_hash_entry *) NULL
 177           && (h->type == bfd_link_hash_defined
 178               || h->type == bfd_link_hash_defweak)
 179           && h->u.def.section->output_section != NULL)
 180         {
 181           if (entry_symbol.name != NULL && entry_from_cmdline)
 182             einfo (_("%P: warning: '--thumb-entry %s' is overriding '-e %s'\n"),
 183                    thumb_entry_symbol, entry_symbol.name);
 184
 185           arm_elf_stringify_thumb_address (h, buffer);
 186           entry_symbol.name = buffer;
 187         }
 188       else
 189         einfo (_("%P: warning: cannot find thumb start symbol %s\n"),
 190                thumb_entry_symbol);
 191     }
 192
 193   /* If init is a Thumb function set the LSB.  */
 194   h = bfd_link_hash_lookup (link_info.hash, link_info.init_function, false,
 195                             false, true);
 196
 197   if (h != (struct bfd_link_hash_entry *) NULL
 198       && (h->type == bfd_link_hash_defined
 199           || h->type == bfd_link_hash_defweak)
 200       && ELF_ST_TYPE (((struct elf_link_hash_entry *)h)->type) == STT_ARM_TFUNC
 201       && h->u.def.section->output_section != NULL)
 202     {
 203       static char buffer[32];
 204
 205       arm_elf_stringify_thumb_address (h, buffer);
 206       link_info.init_function = buffer;
 207     }
 208
 209   /* If fini is a Thumb function set the LSB.  */
 210   h = bfd_link_hash_lookup (link_info.hash, link_info.fini_function, false,
 211                             false, true);
 212
 213   if (h != (struct bfd_link_hash_entry *) NULL
 214       && (h->type == bfd_link_hash_defined
 215           || h->type == bfd_link_hash_defweak)
 216       && ELF_ST_TYPE (((struct elf_link_hash_entry *)h)->type) == STT_ARM_TFUNC
 217       && h->u.def.section->output_section != NULL)
 218     {
 219       static char buffer[32];
 220
 221       arm_elf_stringify_thumb_address (h, buffer);
 222       link_info.fini_function = buffer;
 223     }
 224 }
 225
 226 EOF
 227
 228 # Define some shell vars to insert bits of code into the standard elf
 229 # parse_args and list_options functions.
 230 #
 231 PARSE_AND_LIST_PROLOGUE='
 232 #define OPTION_THUMB_ENTRY              301
 233 '
 234
 235 # Note we add 'n' to the short option list in order to prevent
 236 # getopt_long_only from thinking that -n is a unique abbreviation
 237 # for --no-pipeline-knowledge.  There is no case to handle 'n' here
 238 # however, so instead it will be passed back to parse_args() in
 239 # lexsup.c where it will be handled.
 240 PARSE_AND_LIST_SHORTOPTS=pn
 241
 242 PARSE_AND_LIST_LONGOPTS='
 243   { "no-pipeline-knowledge", no_argument, NULL, '\'p\''},
 244   { "thumb-entry", required_argument, NULL, OPTION_THUMB_ENTRY},
 245 '
 246
 247 PARSE_AND_LIST_OPTIONS='
 248   fprintf (file, _("  -p --no-pipeline-knowledge  Stop the linker knowing about the pipeline length\n"));
 249   fprintf (file, _("     --thumb-entry=<sym>      Set the entry point to be Thumb symbol <sym>\n"));
 250 '
 251
 252 PARSE_AND_LIST_ARGS_CASES='
 253     case '\'p\'':
 254       no_pipeline_knowledge = 1;
 255       break;
 256
 257     case OPTION_THUMB_ENTRY:
 258       thumb_entry_symbol = optarg;
 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
 267 # Replace the elf before_parse function with our own.
 268 LDEMUL_BEFORE_PARSE=gld"${EMULATION_NAME}"_before_parse
 269
 270 # Call the extra arm-elf function
 271 LDEMUL_FINISH=arm_elf_finish