ld/emultempl/m68hc1xelf.em

   1 # This shell script emits a C file. -*- C -*-
   2 #   Copyright 1991, 1993, 1994, 1997, 1999, 2000, 2001, 2002, 2003
   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 m68hc12-elf
  23 # and m68hc11-elf specific routines.  It is used to generate the
  24 # HC11/HC12 trampolines to call a far function by using a normal 'jsr/bsr'.
  25 #
  26 # - The HC11/HC12 relocations are checked to see if there is a
  27 #   R_M68HC11_16 relocation to a symbol marked with STO_M68HC12_FAR.
  28 #   This relocation cannot be made on the symbol but must be made on
  29 #   its trampoline
  30 #   The trampolines to generate are collected during this pass
  31 #   (See elf32_m68hc11_size_stubs)
  32 #
  33 # - The trampolines are generated in a ".tramp" section.  The generation
  34 #   takes care of HC11 and HC12 specificities.
  35 #   (See elf32_m68hc11_build_stubs)
  36 #
  37 # - During relocation the R_M68HC11_16 relocation to the far symbols
  38 #   are redirected to the trampoline that was generated.
  39 #
  40 # Copied from hppaelf and adapted for M68HC11/M68HC12 specific needs.
  41 #
  42 cat >>e${EMULATION_NAME}.c <<EOF
  43
  44 #include "ldctor.h"
  45 #include "elf32-m68hc1x.h"
  46
  47 static void m68hc11elf_create_output_section_statements PARAMS ((void));
  48 static asection *m68hc11elf_add_stub_section
  49   PARAMS ((const char *, asection *));
  50 static void gld${EMULATION_NAME}_finish PARAMS ((void));
  51 static void m68hc11_elf_${EMULATION_NAME}_before_allocation PARAMS ((void));
  52
  53
  54 /* Fake input file for stubs.  */
  55 static lang_input_statement_type *stub_file;
  56
  57 /* By default the HC11/HC12 trampolines to call a far function using
  58    a normal 'bsr' and 'jsr' convention are generated during the link.
  59    The --no-trampoline option prevents that.  */
  60 static int no_trampoline = 0;
  61
  62 /* Name of memory bank window in the MEMORY description.
  63    This is set by --bank-window option.  */
  64 static const char* bank_window_name = 0;
  65
  66 static void
  67 m68hc11_elf_${EMULATION_NAME}_before_allocation ()
  68 {
  69   lang_memory_region_type* region;
  70   int ret;
  71
  72   gld${EMULATION_NAME}_before_allocation ();
  73
  74   /* If generating a relocatable output file, then we don't
  75      have to generate the trampolines.  */
  76   if (link_info.relocatable)
  77     return;
  78
  79   ret = elf32_m68hc11_setup_section_lists (output_bfd, &link_info);
  80   if (ret != 0 && no_trampoline == 0)
  81     {
  82       if (ret < 0)
  83         {
  84           einfo ("%X%P: can not size stub section: %E\n");
  85           return;
  86         }
  87
  88       /* Call into the BFD backend to do the real work.  */
  89       if (!elf32_m68hc11_size_stubs (output_bfd,
  90                                      stub_file->the_bfd,
  91                                      &link_info,
  92                                      &m68hc11elf_add_stub_section))
  93         {
  94           einfo ("%X%P: can not size stub section: %E\n");
  95           return;
  96         }
  97     }
  98
  99   if (bank_window_name == 0)
 100     return;
 101
 102   /* The 'bank_window_name' memory region is a special region that describes
 103      the memory bank window to access to paged memory.  For 68HC12
 104      this is fixed and should be:
 105
 106      window (rx) : ORIGIN = 0x8000, LENGTH = 16K
 107
 108      But for 68HC11 this is board specific.  The definition of such
 109      memory region allows to control how this paged memory is accessed.  */
 110   region = lang_memory_region_lookup (bank_window_name);
 111
 112   /* Check the length to see if it was defined in the script.  */
 113   if (region->length != 0)
 114     {
 115       struct m68hc11_page_info *pinfo;
 116       unsigned i;
 117
 118       /* Get default values  */
 119       m68hc11_elf_get_bank_parameters (&link_info);
 120       pinfo = &m68hc11_elf_hash_table (&link_info)->pinfo;
 121
 122       /* And override them with the region definition.  */
 123       pinfo->bank_size = region->length;
 124       pinfo->bank_shift = 0;
 125       for (i = pinfo->bank_size; i != 0; i >>= 1)
 126         pinfo->bank_shift++;
 127       pinfo->bank_shift--;
 128       pinfo->bank_size = 1L << pinfo->bank_shift;
 129       pinfo->bank_mask = (1 << pinfo->bank_shift) - 1;
 130       pinfo->bank_physical = region->origin;
 131       pinfo->bank_physical_end = region->origin + pinfo->bank_size;
 132
 133       if (pinfo->bank_size != region->length)
 134         {
 135           einfo (_("warning: the size of the 'window' memory region "
 136                    "is not a power of 2\n"));
 137           einfo (_("warning: its size %d is truncated to %d\n"),
 138                  region->length, pinfo->bank_size);
 139         }
 140     }
 141 }
 142
 143 /* This is called before the input files are opened.  We create a new
 144    fake input file to hold the stub sections.  */
 145
 146 static void
 147 m68hc11elf_create_output_section_statements ()
 148 {
 149   stub_file = lang_add_input_file ("linker stubs",
 150                                    lang_input_file_is_fake_enum,
 151                                    NULL);
 152   stub_file->the_bfd = bfd_create ("linker stubs", output_bfd);
 153   if (stub_file->the_bfd == NULL
 154       || !bfd_set_arch_mach (stub_file->the_bfd,
 155                              bfd_get_arch (output_bfd),
 156                              bfd_get_mach (output_bfd)))
 157     {
 158       einfo ("%X%P: can not create BFD %E\n");
 159       return;
 160     }
 161
 162   ldlang_add_file (stub_file);
 163 }
 164
 165
 166 struct hook_stub_info
 167 {
 168   lang_statement_list_type add;
 169   asection *input_section;
 170 };
 171
 172 /* Traverse the linker tree to find the spot where the stub goes.  */
 173
 174 static bfd_boolean hook_in_stub
 175   PARAMS ((struct hook_stub_info *, lang_statement_union_type **));
 176
 177 static bfd_boolean
 178 hook_in_stub (info, lp)
 179      struct hook_stub_info *info;
 180      lang_statement_union_type **lp;
 181 {
 182   lang_statement_union_type *l;
 183   bfd_boolean ret;
 184
 185   for (; (l = *lp) != NULL; lp = &l->header.next)
 186     {
 187       switch (l->header.type)
 188         {
 189         case lang_constructors_statement_enum:
 190           ret = hook_in_stub (info, &constructor_list.head);
 191           if (ret)
 192             return ret;
 193           break;
 194
 195         case lang_output_section_statement_enum:
 196           ret = hook_in_stub (info,
 197                               &l->output_section_statement.children.head);
 198           if (ret)
 199             return ret;
 200           break;
 201
 202         case lang_wild_statement_enum:
 203           ret = hook_in_stub (info, &l->wild_statement.children.head);
 204           if (ret)
 205             return ret;
 206           break;
 207
 208         case lang_group_statement_enum:
 209           ret = hook_in_stub (info, &l->group_statement.children.head);
 210           if (ret)
 211             return ret;
 212           break;
 213
 214         case lang_input_section_enum:
 215           if (l->input_section.section == info->input_section
 216               || strcmp (bfd_get_section_name (output_section,
 217                                                l->input_section.section),
 218                          bfd_get_section_name (output_section,
 219                                                info->input_section)) == 0)
 220             {
 221               /* We've found our section.  Insert the stub immediately
 222                  before its associated input section.  */
 223               *lp = info->add.head;
 224               *(info->add.tail) = l;
 225               return TRUE;
 226             }
 227           break;
 228
 229         case lang_data_statement_enum:
 230         case lang_reloc_statement_enum:
 231         case lang_object_symbols_statement_enum:
 232         case lang_output_statement_enum:
 233         case lang_target_statement_enum:
 234         case lang_input_statement_enum:
 235         case lang_assignment_statement_enum:
 236         case lang_padding_statement_enum:
 237         case lang_address_statement_enum:
 238         case lang_fill_statement_enum:
 239           break;
 240
 241         default:
 242           FAIL ();
 243           break;
 244         }
 245     }
 246   return FALSE;
 247 }
 248
 249
 250 /* Call-back for elf32_m68hc11_size_stubs.  */
 251
 252 /* Create a new stub section, and arrange for it to be linked
 253    immediately before INPUT_SECTION.  */
 254
 255 static asection *
 256 m68hc11elf_add_stub_section (stub_sec_name, tramp_section)
 257      const char *stub_sec_name;
 258      asection *tramp_section;
 259 {
 260   asection *stub_sec;
 261   flagword flags;
 262   asection *output_section;
 263   const char *secname;
 264   lang_output_section_statement_type *os;
 265   struct hook_stub_info info;
 266
 267   stub_sec = bfd_make_section_anyway (stub_file->the_bfd, stub_sec_name);
 268   if (stub_sec == NULL)
 269     goto err_ret;
 270
 271   flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE
 272            | SEC_HAS_CONTENTS | SEC_RELOC | SEC_IN_MEMORY | SEC_KEEP);
 273   if (!bfd_set_section_flags (stub_file->the_bfd, stub_sec, flags))
 274     goto err_ret;
 275
 276   output_section = tramp_section->output_section;
 277   secname = bfd_get_section_name (output_section->owner, output_section);
 278   os = lang_output_section_find (secname);
 279
 280   /* Try to put the new section at the same place as an existing
 281      .tramp section.  Such .tramp section exists in most cases and
 282      contains the trampoline code.  This way we put the generated trampoline
 283      at the correct place.  */
 284   info.input_section = tramp_section;
 285   lang_list_init (&info.add);
 286   lang_add_section (&info.add, stub_sec, os, stub_file);
 287
 288   if (info.add.head == NULL)
 289     goto err_ret;
 290
 291   if (hook_in_stub (&info, &os->children.head))
 292     return stub_sec;
 293
 294  err_ret:
 295   einfo ("%X%P: can not make stub section: %E\n");
 296   return NULL;
 297 }
 298
 299 /* Final emulation specific call.  For the 68HC12 we use this opportunity
 300    to build linker stubs.  */
 301
 302 static void
 303 gld${EMULATION_NAME}_finish ()
 304 {
 305   /* Now build the linker stubs.  */
 306   if (stub_file->the_bfd->sections != NULL)
 307     {
 308       /* Call again the trampoline analyzer to initialize the trampoline
 309          stubs with the correct symbol addresses.  Since there could have
 310          been relaxation, the symbol addresses that were found during
 311          first call may no longer be correct.  */
 312       if (!elf32_m68hc11_size_stubs (output_bfd,
 313                                      stub_file->the_bfd,
 314                                      &link_info, 0))
 315         {
 316           einfo ("%X%P: can not size stub section: %E\n");
 317           return;
 318         }
 319       if (!elf32_m68hc11_build_stubs (output_bfd, &link_info))
 320         einfo ("%X%P: can not build stubs: %E\n");
 321     }
 322 }
 323
 324
 325 /* Avoid processing the fake stub_file in vercheck, stat_needed and
 326    check_needed routines.  */
 327
 328 static void m68hc11_for_each_input_file_wrapper
 329   PARAMS ((lang_input_statement_type *));
 330 static void m68hc11_lang_for_each_input_file
 331   PARAMS ((void (*) (lang_input_statement_type *)));
 332
 333 static void (*real_func) PARAMS ((lang_input_statement_type *));
 334
 335 static void m68hc11_for_each_input_file_wrapper (l)
 336      lang_input_statement_type *l;
 337 {
 338   if (l != stub_file)
 339     (*real_func) (l);
 340 }
 341
 342 static void
 343 m68hc11_lang_for_each_input_file (func)
 344      void (*func) PARAMS ((lang_input_statement_type *));
 345 {
 346   real_func = func;
 347   lang_for_each_input_file (&m68hc11_for_each_input_file_wrapper);
 348 }
 349
 350 #define lang_for_each_input_file m68hc11_lang_for_each_input_file
 351
 352 EOF
 353
 354 # Define some shell vars to insert bits of code into the standard elf
 355 # parse_args and list_options functions.
 356 #
 357 PARSE_AND_LIST_PROLOGUE='
 358 #define OPTION_NO_TRAMPOLINE            300
 359 #define OPTION_BANK_WINDOW              301
 360 '
 361
 362 # The options are repeated below so that no abbreviations are allowed.
 363 # Otherwise -s matches stub-group-size
 364 PARSE_AND_LIST_LONGOPTS='
 365   { "no-trampoline", no_argument, NULL, OPTION_NO_TRAMPOLINE },
 366   { "bank-window",   required_argument, NULL, OPTION_BANK_WINDOW },
 367 '
 368
 369 PARSE_AND_LIST_OPTIONS='
 370   fprintf (file, _(""
 371 "  --no-trampoline         Do not generate the far trampolines used to call\n"
 372 "                          a far function using 'jsr' or 'bsr'.\n"
 373 "  --bank-window NAME      Specify the name of the memory region describing\n"
 374 "                          the layout of the memory bank window.\n"
 375                    ));
 376 '
 377
 378 PARSE_AND_LIST_ARGS_CASES='
 379     case OPTION_NO_TRAMPOLINE:
 380       no_trampoline = 1;
 381       break;
 382     case OPTION_BANK_WINDOW:
 383       bank_window_name = optarg;
 384       break;
 385 '
 386
 387 # Put these extra m68hc11elf routines in ld_${EMULATION_NAME}_emulation
 388 #
 389 LDEMUL_BEFORE_ALLOCATION=m68hc11_elf_${EMULATION_NAME}_before_allocation
 390 LDEMUL_FINISH=gld${EMULATION_NAME}_finish
 391 LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=m68hc11elf_create_output_section_statements