ld/emultempl/hppaelf.em

   1 # This shell script emits a C file. -*- C -*-
   2 #   Copyright (C) 1991-2015 Free Software Foundation, Inc.
   3 #
   4 # This file is part of the GNU Binutils.
   5 #
   6 # This program is free software; you can redistribute it and/or modify
   7 # it under the terms of the GNU General Public License as published by
   8 # the Free Software Foundation; either version 3 of the License, or
   9 # (at your option) any later version.
  10 #
  11 # This program is distributed in the hope that it will be useful,
  12 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 # GNU General Public License for more details.
  15 #
  16 # You should have received a copy of the GNU General Public License
  17 # along with this program; if not, write to the Free Software
  18 # Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  19 # MA 02110-1301, USA.
  20 #
  21
  22 # This file is sourced from elf32.em, and defines extra hppa-elf
  23 # specific routines.
  24 #
  25 fragment <<EOF
  26
  27 #include "ldctor.h"
  28 #include "elf32-hppa.h"
  29
  30
  31 /* Fake input file for stubs.  */
  32 static lang_input_statement_type *stub_file;
  33
  34 /* Type of import/export stubs to build.  For a single sub-space model,
  35    we can build smaller import stubs and there is no need for export
  36    stubs.  */
  37 static int multi_subspace = 0;
  38
  39 /* Whether we need to call hppa_layout_sections_again.  */
  40 static int need_laying_out = 0;
  41
  42 /* Maximum size of a group of input sections that can be handled by
  43    one stub section.  A value of +/-1 indicates the bfd back-end
  44    should use a suitable default size.  */
  45 static bfd_signed_vma group_size = 1;
  46
  47 /* Stops the linker merging .text sections on a relocatable link,
  48    and adds millicode library to the list of input files.  */
  49
  50 static void
  51 hppaelf_after_parse (void)
  52 {
  53   if (bfd_link_relocatable (&link_info))
  54     lang_add_unique (".text");
  55
  56   /* Enable this once we split millicode stuff from libgcc:
  57      lang_add_input_file ("milli",
  58                           lang_input_file_is_l_enum,
  59                           NULL);
  60   */
  61
  62   gld${EMULATION_NAME}_after_parse ();
  63 }
  64
  65 /* This is called before the input files are opened.  We create a new
  66    fake input file to hold the stub sections.  */
  67
  68 static void
  69 hppaelf_create_output_section_statements (void)
  70 {
  71   if (!(bfd_get_flavour (link_info.output_bfd) == bfd_target_elf_flavour
  72         && (elf_object_id (link_info.output_bfd) == HPPA32_ELF_DATA
  73             || elf_object_id (link_info.output_bfd) == HPPA64_ELF_DATA)))
  74     return;
  75
  76   stub_file = lang_add_input_file ("linker stubs",
  77                                    lang_input_file_is_fake_enum,
  78                                    NULL);
  79   stub_file->the_bfd = bfd_create ("linker stubs", link_info.output_bfd);
  80   if (stub_file->the_bfd == NULL
  81       || ! bfd_set_arch_mach (stub_file->the_bfd,
  82                               bfd_get_arch (link_info.output_bfd),
  83                               bfd_get_mach (link_info.output_bfd)))
  84     {
  85       einfo ("%X%P: can not create BFD %E\n");
  86       return;
  87     }
  88
  89   stub_file->the_bfd->flags |= BFD_LINKER_CREATED;
  90   ldlang_add_file (stub_file);
  91 }
  92
  93
  94 struct hook_stub_info
  95 {
  96   lang_statement_list_type add;
  97   asection *input_section;
  98 };
  99
 100 /* Traverse the linker tree to find the spot where the stub goes.  */
 101
 102 static bfd_boolean
 103 hook_in_stub (struct hook_stub_info *info, lang_statement_union_type **lp)
 104 {
 105   lang_statement_union_type *l;
 106   bfd_boolean ret;
 107
 108   for (; (l = *lp) != NULL; lp = &l->header.next)
 109     {
 110       switch (l->header.type)
 111         {
 112         case lang_constructors_statement_enum:
 113           ret = hook_in_stub (info, &constructor_list.head);
 114           if (ret)
 115             return ret;
 116           break;
 117
 118         case lang_output_section_statement_enum:
 119           ret = hook_in_stub (info,
 120                               &l->output_section_statement.children.head);
 121           if (ret)
 122             return ret;
 123           break;
 124
 125         case lang_wild_statement_enum:
 126           ret = hook_in_stub (info, &l->wild_statement.children.head);
 127           if (ret)
 128             return ret;
 129           break;
 130
 131         case lang_group_statement_enum:
 132           ret = hook_in_stub (info, &l->group_statement.children.head);
 133           if (ret)
 134             return ret;
 135           break;
 136
 137         case lang_input_section_enum:
 138           if (l->input_section.section == info->input_section)
 139             {
 140               /* We've found our section.  Insert the stub immediately
 141                  before its associated input section.  */
 142               *lp = info->add.head;
 143               *(info->add.tail) = l;
 144               return TRUE;
 145             }
 146           break;
 147
 148         case lang_data_statement_enum:
 149         case lang_reloc_statement_enum:
 150         case lang_object_symbols_statement_enum:
 151         case lang_output_statement_enum:
 152         case lang_target_statement_enum:
 153         case lang_input_statement_enum:
 154         case lang_assignment_statement_enum:
 155         case lang_padding_statement_enum:
 156         case lang_address_statement_enum:
 157         case lang_fill_statement_enum:
 158           break;
 159
 160         default:
 161           FAIL ();
 162           break;
 163         }
 164     }
 165   return FALSE;
 166 }
 167
 168
 169 /* Call-back for elf32_hppa_size_stubs.  */
 170
 171 /* Create a new stub section, and arrange for it to be linked
 172    immediately before INPUT_SECTION.  */
 173
 174 static asection *
 175 hppaelf_add_stub_section (const char *stub_sec_name, asection *input_section)
 176 {
 177   asection *stub_sec;
 178   flagword flags;
 179   asection *output_section;
 180   lang_output_section_statement_type *os;
 181   struct hook_stub_info info;
 182
 183   flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE
 184            | SEC_HAS_CONTENTS | SEC_RELOC | SEC_IN_MEMORY | SEC_KEEP);
 185   stub_sec = bfd_make_section_anyway_with_flags (stub_file->the_bfd,
 186                                                  stub_sec_name, flags);
 187   if (stub_sec == NULL)
 188     goto err_ret;
 189
 190   output_section = input_section->output_section;
 191   os = lang_output_section_get (output_section);
 192
 193   info.input_section = input_section;
 194   lang_list_init (&info.add);
 195   lang_add_section (&info.add, stub_sec, NULL, os);
 196
 197   if (info.add.head == NULL)
 198     goto err_ret;
 199
 200   if (hook_in_stub (&info, &os->children.head))
 201     return stub_sec;
 202
 203  err_ret:
 204   einfo ("%X%P: can not make stub section: %E\n");
 205   return NULL;
 206 }
 207
 208
 209 /* Another call-back for elf32_hppa_size_stubs.  */
 210
 211 static void
 212 hppaelf_layout_sections_again (void)
 213 {
 214   /* If we have changed sizes of the stub sections, then we need
 215      to recalculate all the section offsets.  This may mean we need to
 216      add even more stubs.  */
 217   gld${EMULATION_NAME}_map_segments (TRUE);
 218   need_laying_out = -1;
 219 }
 220
 221
 222 static void
 223 build_section_lists (lang_statement_union_type *statement)
 224 {
 225   if (statement->header.type == lang_input_section_enum)
 226     {
 227       asection *i = statement->input_section.section;
 228
 229       if (i->sec_info_type != SEC_INFO_TYPE_JUST_SYMS
 230           && (i->flags & SEC_EXCLUDE) == 0
 231           && i->output_section != NULL
 232           && i->output_section->owner == link_info.output_bfd)
 233         {
 234           elf32_hppa_next_input_section (&link_info, i);
 235         }
 236     }
 237 }
 238
 239
 240 /* For the PA we use this opportunity to size and build linker stubs.  */
 241
 242 static void
 243 gld${EMULATION_NAME}_after_allocation (void)
 244 {
 245   int ret;
 246
 247   /* bfd_elf_discard_info just plays with data and debugging sections,
 248      ie. doesn't affect code size, so we can delay resizing the
 249      sections.  It's likely we'll resize everything in the process of
 250      adding stubs.  */
 251   ret = bfd_elf_discard_info (link_info.output_bfd, &link_info);
 252   if (ret < 0)
 253     {
 254       einfo ("%X%P: .eh_frame/.stab edit: %E\n");
 255       return;
 256     }
 257   else if (ret > 0)
 258     need_laying_out = 1;
 259
 260   /* If generating a relocatable output file, then we don't
 261      have to examine the relocs.  */
 262   if (stub_file != NULL && !bfd_link_relocatable (&link_info))
 263     {
 264       ret = elf32_hppa_setup_section_lists (link_info.output_bfd, &link_info);
 265       if (ret != 0)
 266         {
 267           if (ret < 0)
 268             {
 269               einfo ("%X%P: can not size stub section: %E\n");
 270               return;
 271             }
 272
 273           lang_for_each_statement (build_section_lists);
 274
 275           /* Call into the BFD backend to do the real work.  */
 276           if (! elf32_hppa_size_stubs (link_info.output_bfd,
 277                                        stub_file->the_bfd,
 278                                        &link_info,
 279                                        multi_subspace,
 280                                        group_size,
 281                                        &hppaelf_add_stub_section,
 282                                        &hppaelf_layout_sections_again))
 283             {
 284               einfo ("%X%P: can not size stub section: %E\n");
 285               return;
 286             }
 287         }
 288     }
 289
 290   if (need_laying_out != -1)
 291     gld${EMULATION_NAME}_map_segments (need_laying_out);
 292
 293   if (!bfd_link_relocatable (&link_info))
 294     {
 295       /* Set the global data pointer.  */
 296       if (! elf32_hppa_set_gp (link_info.output_bfd, &link_info))
 297         {
 298           einfo ("%X%P: can not set gp\n");
 299           return;
 300         }
 301
 302       /* Now build the linker stubs.  */
 303       if (stub_file != NULL && stub_file->the_bfd->sections != NULL)
 304         {
 305           if (! elf32_hppa_build_stubs (&link_info))
 306             einfo ("%X%P: can not build stubs: %E\n");
 307         }
 308     }
 309 }
 310
 311
 312 /* Avoid processing the fake stub_file in vercheck, stat_needed and
 313    check_needed routines.  */
 314
 315 static void (*real_func) (lang_input_statement_type *);
 316
 317 static void hppa_for_each_input_file_wrapper (lang_input_statement_type *l)
 318 {
 319   if (l != stub_file)
 320     (*real_func) (l);
 321 }
 322
 323 static void
 324 hppa_lang_for_each_input_file (void (*func) (lang_input_statement_type *))
 325 {
 326   real_func = func;
 327   lang_for_each_input_file (&hppa_for_each_input_file_wrapper);
 328 }
 329
 330 #define lang_for_each_input_file hppa_lang_for_each_input_file
 331
 332 EOF
 333
 334 # Define some shell vars to insert bits of code into the standard elf
 335 # parse_args and list_options functions.
 336 #
 337 PARSE_AND_LIST_PROLOGUE='
 338 #define OPTION_MULTI_SUBSPACE           301
 339 #define OPTION_STUBGROUP_SIZE           (OPTION_MULTI_SUBSPACE + 1)
 340 '
 341
 342 PARSE_AND_LIST_LONGOPTS='
 343   { "multi-subspace", no_argument, NULL, OPTION_MULTI_SUBSPACE },
 344   { "stub-group-size", required_argument, NULL, OPTION_STUBGROUP_SIZE },
 345 '
 346
 347 PARSE_AND_LIST_OPTIONS='
 348   fprintf (file, _("\
 349   --multi-subspace            Generate import and export stubs to support\n\
 350                                 multiple sub-space shared libraries\n"
 351                    ));
 352   fprintf (file, _("\
 353   --stub-group-size=N         Maximum size of a group of input sections that\n\
 354                                 can be handled by one stub section.  A negative\n\
 355                                 value locates all stubs before their branches\n\
 356                                 (with a group size of -N), while a positive\n\
 357                                 value allows two groups of input sections, one\n\
 358                                 before, and one after each stub section.\n\
 359                                 Values of +/-1 indicate the linker should\n\
 360                                 choose suitable defaults.\n"
 361                    ));
 362 '
 363
 364 PARSE_AND_LIST_ARGS_CASES='
 365     case OPTION_MULTI_SUBSPACE:
 366       multi_subspace = 1;
 367       break;
 368
 369     case OPTION_STUBGROUP_SIZE:
 370       {
 371         const char *end;
 372         group_size = bfd_scan_vma (optarg, &end, 0);
 373         if (*end)
 374           einfo (_("%P%F: invalid number `%s'\''\n"), optarg);
 375       }
 376       break;
 377 '
 378
 379 # Put these extra hppaelf routines in ld_${EMULATION_NAME}_emulation
 380 #
 381 LDEMUL_AFTER_PARSE=hppaelf_after_parse
 382 LDEMUL_AFTER_ALLOCATION=gld${EMULATION_NAME}_after_allocation
 383 LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=hppaelf_create_output_section_statements