ld/emultempl/hppaelf.em

   1 # This shell script emits a C file. -*- C -*-
   2 #   Copyright (C) 1991-2021 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 elf.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   ldelf_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 (_("%F%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   elf32_hppa_init_stub_bfd (stub_file->the_bfd, &link_info);
  92 }
  93
  94
  95 struct hook_stub_info
  96 {
  97   lang_statement_list_type add;
  98   asection *input_section;
  99 };
 100
 101 /* Traverse the linker tree to find the spot where the stub goes.  */
 102
 103 static bfd_boolean
 104 hook_in_stub (struct hook_stub_info *info, lang_statement_union_type **lp)
 105 {
 106   lang_statement_union_type *l;
 107   bfd_boolean ret;
 108
 109   for (; (l = *lp) != NULL; lp = &l->header.next)
 110     {
 111       switch (l->header.type)
 112         {
 113         case lang_constructors_statement_enum:
 114           ret = hook_in_stub (info, &constructor_list.head);
 115           if (ret)
 116             return ret;
 117           break;
 118
 119         case lang_output_section_statement_enum:
 120           ret = hook_in_stub (info,
 121                               &l->output_section_statement.children.head);
 122           if (ret)
 123             return ret;
 124           break;
 125
 126         case lang_wild_statement_enum:
 127           ret = hook_in_stub (info, &l->wild_statement.children.head);
 128           if (ret)
 129             return ret;
 130           break;
 131
 132         case lang_group_statement_enum:
 133           ret = hook_in_stub (info, &l->group_statement.children.head);
 134           if (ret)
 135             return ret;
 136           break;
 137
 138         case lang_input_section_enum:
 139           if (l->input_section.section == info->input_section)
 140             {
 141               /* We've found our section.  Insert the stub immediately
 142                  before its associated input section.  */
 143               *lp = info->add.head;
 144               *(info->add.tail) = l;
 145               return TRUE;
 146             }
 147           break;
 148
 149         case lang_data_statement_enum:
 150         case lang_reloc_statement_enum:
 151         case lang_object_symbols_statement_enum:
 152         case lang_output_statement_enum:
 153         case lang_target_statement_enum:
 154         case lang_input_statement_enum:
 155         case lang_assignment_statement_enum:
 156         case lang_padding_statement_enum:
 157         case lang_address_statement_enum:
 158         case lang_fill_statement_enum:
 159           break;
 160
 161         default:
 162           FAIL ();
 163           break;
 164         }
 165     }
 166   return FALSE;
 167 }
 168
 169
 170 /* Call-back for elf32_hppa_size_stubs.  */
 171
 172 /* Create a new stub section, and arrange for it to be linked
 173    immediately before INPUT_SECTION.  */
 174
 175 static asection *
 176 hppaelf_add_stub_section (const char *stub_sec_name, asection *input_section)
 177 {
 178   asection *stub_sec;
 179   flagword flags;
 180   asection *output_section;
 181   lang_output_section_statement_type *os;
 182   struct hook_stub_info info;
 183
 184   flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE
 185            | SEC_HAS_CONTENTS | SEC_RELOC | SEC_IN_MEMORY | SEC_KEEP);
 186   stub_sec = bfd_make_section_anyway_with_flags (stub_file->the_bfd,
 187                                                  stub_sec_name, flags);
 188   if (stub_sec == NULL)
 189     goto err_ret;
 190
 191   output_section = input_section->output_section;
 192   os = lang_output_section_get (output_section);
 193
 194   info.input_section = input_section;
 195   lang_list_init (&info.add);
 196   lang_add_section (&info.add, stub_sec, NULL, os);
 197
 198   if (info.add.head == NULL)
 199     goto err_ret;
 200
 201   if (hook_in_stub (&info, &os->children.head))
 202     return stub_sec;
 203
 204  err_ret:
 205   einfo (_("%X%P: can not make stub section: %E\n"));
 206   return NULL;
 207 }
 208
 209
 210 /* Another call-back for elf32_hppa_size_stubs.  */
 211
 212 static void
 213 hppaelf_layout_sections_again (void)
 214 {
 215   /* If we have changed sizes of the stub sections, then we need
 216      to recalculate all the section offsets.  This may mean we need to
 217      add even more stubs.  */
 218   ldelf_map_segments (TRUE);
 219   need_laying_out = -1;
 220 }
 221
 222
 223 static void
 224 build_section_lists (lang_statement_union_type *statement)
 225 {
 226   if (statement->header.type == lang_input_section_enum)
 227     {
 228       asection *i = statement->input_section.section;
 229
 230       if (i->sec_info_type != SEC_INFO_TYPE_JUST_SYMS
 231           && (i->flags & SEC_EXCLUDE) == 0
 232           && i->output_section != NULL
 233           && i->output_section->owner == link_info.output_bfd)
 234         {
 235           elf32_hppa_next_input_section (&link_info, i);
 236         }
 237     }
 238 }
 239
 240
 241 /* For the PA we use this opportunity to size and build linker stubs.  */
 242
 243 static void
 244 gld${EMULATION_NAME}_after_allocation (void)
 245 {
 246   int ret;
 247
 248   /* bfd_elf_discard_info just plays with data and debugging sections,
 249      ie. doesn't affect code size, so we can delay resizing the
 250      sections.  It's likely we'll resize everything in the process of
 251      adding stubs.  */
 252   ret = bfd_elf_discard_info (link_info.output_bfd, &link_info);
 253   if (ret < 0)
 254     {
 255       einfo (_("%X%P: .eh_frame/.stab edit: %E\n"));
 256       return;
 257     }
 258   else if (ret > 0)
 259     need_laying_out = 1;
 260
 261   /* If generating a relocatable output file, then we don't
 262      have to examine the relocs.  */
 263   if (stub_file != NULL && !bfd_link_relocatable (&link_info))
 264     {
 265       ret = elf32_hppa_setup_section_lists (link_info.output_bfd, &link_info);
 266       if (ret != 0)
 267         {
 268           if (ret < 0)
 269             {
 270               einfo (_("%X%P: can not size stub section: %E\n"));
 271               return;
 272             }
 273
 274           lang_for_each_statement (build_section_lists);
 275
 276           /* Call into the BFD backend to do the real work.  */
 277           if (! elf32_hppa_size_stubs (link_info.output_bfd,
 278                                        stub_file->the_bfd,
 279                                        &link_info,
 280                                        multi_subspace,
 281                                        group_size,
 282                                        &hppaelf_add_stub_section,
 283                                        &hppaelf_layout_sections_again))
 284             {
 285               einfo (_("%X%P: can not size stub section: %E\n"));
 286               return;
 287             }
 288         }
 289     }
 290
 291   if (need_laying_out != -1)
 292     ldelf_map_segments (need_laying_out);
 293
 294   if (!bfd_link_relocatable (&link_info))
 295     {
 296       /* Set the global data pointer.  */
 297       if (! elf32_hppa_set_gp (link_info.output_bfd, &link_info))
 298         {
 299           einfo (_("%X%P: can not set gp\n"));
 300           return;
 301         }
 302
 303       /* Now build the linker stubs.  */
 304       if (stub_file != NULL && stub_file->the_bfd->sections != NULL)
 305         {
 306           if (! elf32_hppa_build_stubs (&link_info))
 307             einfo (_("%X%P: can not build stubs: %E\n"));
 308         }
 309     }
 310 }
 311
 312 EOF
 313
 314 # Define some shell vars to insert bits of code into the standard elf
 315 # parse_args and list_options functions.
 316 #
 317 PARSE_AND_LIST_PROLOGUE='
 318 #define OPTION_MULTI_SUBSPACE           301
 319 #define OPTION_STUBGROUP_SIZE           (OPTION_MULTI_SUBSPACE + 1)
 320 '
 321
 322 PARSE_AND_LIST_LONGOPTS='
 323   { "multi-subspace", no_argument, NULL, OPTION_MULTI_SUBSPACE },
 324   { "stub-group-size", required_argument, NULL, OPTION_STUBGROUP_SIZE },
 325 '
 326
 327 PARSE_AND_LIST_OPTIONS='
 328   fprintf (file, _("\
 329   --multi-subspace            Generate import and export stubs to support\n\
 330                                 multiple sub-space shared libraries\n"
 331                    ));
 332   fprintf (file, _("\
 333   --stub-group-size=N         Maximum size of a group of input sections that\n\
 334                                 can be handled by one stub section.  A negative\n\
 335                                 value locates all stubs before their branches\n\
 336                                 (with a group size of -N), while a positive\n\
 337                                 value allows two groups of input sections, one\n\
 338                                 before, and one after each stub section.\n\
 339                                 Values of +/-1 indicate the linker should\n\
 340                                 choose suitable defaults.\n"
 341                    ));
 342 '
 343
 344 PARSE_AND_LIST_ARGS_CASES='
 345     case OPTION_MULTI_SUBSPACE:
 346       multi_subspace = 1;
 347       break;
 348
 349     case OPTION_STUBGROUP_SIZE:
 350       {
 351         const char *end;
 352         group_size = bfd_scan_vma (optarg, &end, 0);
 353         if (*end)
 354           einfo (_("%F%P: invalid number `%s'\''\n"), optarg);
 355       }
 356       break;
 357 '
 358
 359 # Put these extra hppaelf routines in ld_${EMULATION_NAME}_emulation
 360 #
 361 LDEMUL_AFTER_PARSE=hppaelf_after_parse
 362 LDEMUL_AFTER_ALLOCATION=gld${EMULATION_NAME}_after_allocation
 363 LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=hppaelf_create_output_section_statements