ld/emultempl/mipself.em

   1 # This shell script emits a C file. -*- C -*-
   2 #   Copyright (C) 2004-2017 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 fragment <<EOF
  22
  23 #include "ldctor.h"
  24 #include "elf/mips.h"
  25 #include "elfxx-mips.h"
  26
  27 #define is_mips_elf(bfd)                                \
  28   (bfd_get_flavour (bfd) == bfd_target_elf_flavour      \
  29    && elf_tdata (bfd) != NULL                           \
  30    && elf_object_id (bfd) == MIPS_ELF_DATA)
  31
  32 /* Fake input file for stubs.  */
  33 static lang_input_statement_type *stub_file;
  34 static bfd *stub_bfd;
  35
  36 static bfd_boolean insn32;
  37 static bfd_boolean ignore_branch_isa;
  38
  39 static void
  40 mips_after_parse (void)
  41 {
  42   /* .gnu.hash and the MIPS ABI require .dynsym to be sorted in different
  43      ways.  .gnu.hash needs symbols to be grouped by hash code whereas the
  44      MIPS ABI requires a mapping between the GOT and the symbol table.  */
  45   if (link_info.emit_gnu_hash)
  46     {
  47       einfo ("%X%P: .gnu.hash is incompatible with the MIPS ABI\n");
  48       link_info.emit_hash = TRUE;
  49       link_info.emit_gnu_hash = FALSE;
  50     }
  51   gld${EMULATION_NAME}_after_parse ();
  52 }
  53
  54 struct hook_stub_info
  55 {
  56   lang_statement_list_type add;
  57   asection *input_section;
  58 };
  59
  60 /* Traverse the linker tree to find the spot where the stub goes.  */
  61
  62 static bfd_boolean
  63 hook_in_stub (struct hook_stub_info *info, lang_statement_union_type **lp)
  64 {
  65   lang_statement_union_type *l;
  66   bfd_boolean ret;
  67
  68   for (; (l = *lp) != NULL; lp = &l->header.next)
  69     {
  70       switch (l->header.type)
  71         {
  72         case lang_constructors_statement_enum:
  73           ret = hook_in_stub (info, &constructor_list.head);
  74           if (ret)
  75             return ret;
  76           break;
  77
  78         case lang_output_section_statement_enum:
  79           ret = hook_in_stub (info,
  80                               &l->output_section_statement.children.head);
  81           if (ret)
  82             return ret;
  83           break;
  84
  85         case lang_wild_statement_enum:
  86           ret = hook_in_stub (info, &l->wild_statement.children.head);
  87           if (ret)
  88             return ret;
  89           break;
  90
  91         case lang_group_statement_enum:
  92           ret = hook_in_stub (info, &l->group_statement.children.head);
  93           if (ret)
  94             return ret;
  95           break;
  96
  97         case lang_input_section_enum:
  98           if (info->input_section == NULL
  99               || l->input_section.section == info->input_section)
 100             {
 101               /* We've found our section.  Insert the stub immediately
 102                  before its associated input section.  */
 103               *lp = info->add.head;
 104               *(info->add.tail) = l;
 105               return TRUE;
 106             }
 107           break;
 108
 109         case lang_data_statement_enum:
 110         case lang_reloc_statement_enum:
 111         case lang_object_symbols_statement_enum:
 112         case lang_output_statement_enum:
 113         case lang_target_statement_enum:
 114         case lang_input_statement_enum:
 115         case lang_assignment_statement_enum:
 116         case lang_padding_statement_enum:
 117         case lang_address_statement_enum:
 118         case lang_fill_statement_enum:
 119           break;
 120
 121         default:
 122           FAIL ();
 123           break;
 124         }
 125     }
 126   return FALSE;
 127 }
 128
 129 /* Create a new stub section called STUB_SEC_NAME and arrange for it to
 130    be linked in OUTPUT_SECTION.  The section should go at the beginning of
 131    OUTPUT_SECTION if INPUT_SECTION is null, otherwise it must go immediately
 132    before INPUT_SECTION.  */
 133
 134 static asection *
 135 mips_add_stub_section (const char *stub_sec_name, asection *input_section,
 136                        asection *output_section)
 137 {
 138   asection *stub_sec;
 139   flagword flags;
 140   lang_output_section_statement_type *os;
 141   struct hook_stub_info info;
 142
 143   /* PR 12845: If the input section has been garbage collected it will
 144      not have its output section set to *ABS*.  */
 145   if (bfd_is_abs_section (output_section))
 146     return NULL;
 147
 148   /* Create the stub file, if we haven't already.  */
 149   if (stub_file == NULL)
 150     {
 151       stub_file = lang_add_input_file ("linker stubs",
 152                                        lang_input_file_is_fake_enum,
 153                                        NULL);
 154       stub_bfd = bfd_create ("linker stubs", link_info.output_bfd);
 155       if (stub_bfd == NULL
 156           || !bfd_set_arch_mach (stub_bfd,
 157                                  bfd_get_arch (link_info.output_bfd),
 158                                  bfd_get_mach (link_info.output_bfd)))
 159         {
 160           einfo ("%F%P: can not create BFD %E\n");
 161           return NULL;
 162         }
 163       stub_bfd->flags |= BFD_LINKER_CREATED;
 164       stub_file->the_bfd = stub_bfd;
 165       ldlang_add_file (stub_file);
 166     }
 167
 168   /* Create the section.  */
 169   stub_sec = bfd_make_section_anyway (stub_bfd, stub_sec_name);
 170   if (stub_sec == NULL)
 171     goto err_ret;
 172
 173   /* Set the flags.  */
 174   flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE
 175            | SEC_HAS_CONTENTS | SEC_IN_MEMORY | SEC_KEEP);
 176   if (!bfd_set_section_flags (stub_bfd, stub_sec, flags))
 177     goto err_ret;
 178
 179   os = lang_output_section_get (output_section);
 180
 181   /* Initialize a statement list that contains only the new statement.  */
 182   lang_list_init (&info.add);
 183   lang_add_section (&info.add, stub_sec, NULL, os);
 184   if (info.add.head == NULL)
 185     goto err_ret;
 186
 187   /* Insert the new statement in the appropriate place.  */
 188   info.input_section = input_section;
 189   if (hook_in_stub (&info, &os->children.head))
 190     return stub_sec;
 191
 192  err_ret:
 193   einfo ("%X%P: can not make stub section: %E\n");
 194   return NULL;
 195 }
 196
 197 /* This is called before the input files are opened.  */
 198
 199 static void
 200 mips_create_output_section_statements (void)
 201 {
 202   struct elf_link_hash_table *htab;
 203
 204   htab = elf_hash_table (&link_info);
 205   if (is_elf_hash_table (htab) && is_mips_elf (link_info.output_bfd))
 206     _bfd_mips_elf_linker_flags (&link_info, insn32, ignore_branch_isa);
 207
 208   if (is_mips_elf (link_info.output_bfd))
 209     _bfd_mips_elf_init_stubs (&link_info, mips_add_stub_section);
 210 }
 211
 212 /* This is called after we have merged the private data of the input bfds.  */
 213
 214 static void
 215 mips_before_allocation (void)
 216 {
 217   if (is_mips_elf (link_info.output_bfd))
 218     {
 219       flagword flags;
 220
 221       flags = elf_elfheader (link_info.output_bfd)->e_flags;
 222       if (!bfd_link_pic (&link_info)
 223           && !link_info.nocopyreloc
 224           && (flags & (EF_MIPS_PIC | EF_MIPS_CPIC)) == EF_MIPS_CPIC)
 225         _bfd_mips_elf_use_plts_and_copy_relocs (&link_info);
 226     }
 227
 228   gld${EMULATION_NAME}_before_allocation ();
 229 }
 230
 231 /* Avoid processing the fake stub_file in vercheck, stat_needed and
 232    check_needed routines.  */
 233
 234 static void (*real_func) (lang_input_statement_type *);
 235
 236 static void mips_for_each_input_file_wrapper (lang_input_statement_type *l)
 237 {
 238   if (l != stub_file)
 239     (*real_func) (l);
 240 }
 241
 242 static void
 243 mips_lang_for_each_input_file (void (*func) (lang_input_statement_type *))
 244 {
 245   real_func = func;
 246   lang_for_each_input_file (&mips_for_each_input_file_wrapper);
 247 }
 248
 249 #define lang_for_each_input_file mips_lang_for_each_input_file
 250
 251 EOF
 252
 253 # Define some shell vars to insert bits of code into the standard elf
 254 # parse_args and list_options functions.
 255 #
 256 PARSE_AND_LIST_PROLOGUE='
 257 enum
 258   {
 259     OPTION_INSN32 = 301,
 260     OPTION_NO_INSN32,
 261     OPTION_IGNORE_BRANCH_ISA,
 262     OPTION_NO_IGNORE_BRANCH_ISA
 263   };
 264 '
 265
 266 PARSE_AND_LIST_LONGOPTS='
 267   { "insn32", no_argument, NULL, OPTION_INSN32 },
 268   { "no-insn32", no_argument, NULL, OPTION_NO_INSN32 },
 269   { "ignore-branch-isa", no_argument, NULL, OPTION_IGNORE_BRANCH_ISA },
 270   { "no-ignore-branch-isa", no_argument, NULL, OPTION_NO_IGNORE_BRANCH_ISA },
 271 '
 272
 273 PARSE_AND_LIST_OPTIONS='
 274   fprintf (file, _("\
 275   --insn32                    Only generate 32-bit microMIPS instructions\n"
 276                    ));
 277   fprintf (file, _("\
 278   --no-insn32                 Generate all microMIPS instructions\n"
 279                    ));
 280   fprintf (file, _("\
 281   --ignore-branch-isa         Accept invalid branch relocations requiring\n\
 282                               an ISA mode switch\n"
 283                    ));
 284   fprintf (file, _("\
 285   --no-ignore-branch-isa      Reject invalid branch relocations requiring\n\
 286                               an ISA mode switch\n"
 287                    ));
 288 '
 289
 290 PARSE_AND_LIST_ARGS_CASES='
 291     case OPTION_INSN32:
 292       insn32 = TRUE;
 293       break;
 294
 295     case OPTION_NO_INSN32:
 296       insn32 = FALSE;
 297       break;
 298
 299     case OPTION_IGNORE_BRANCH_ISA:
 300       ignore_branch_isa = TRUE;
 301       break;
 302
 303     case OPTION_NO_IGNORE_BRANCH_ISA:
 304       ignore_branch_isa = FALSE;
 305       break;
 306 '
 307
 308 LDEMUL_AFTER_PARSE=mips_after_parse
 309 LDEMUL_BEFORE_ALLOCATION=mips_before_allocation
 310 LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=mips_create_output_section_statements