ld/emultempl/mipself.em

   1 # This shell script emits a C file. -*- C -*-
   2 #   Copyright 2004, 2006, 2007, 2008 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 void
  37 mips_after_parse (void)
  38 {
  39   /* .gnu.hash and the MIPS ABI require .dynsym to be sorted in different
  40      ways.  .gnu.hash needs symbols to be grouped by hash code whereas the
  41      MIPS ABI requires a mapping between the GOT and the symbol table.  */
  42   if (link_info.emit_gnu_hash)
  43     {
  44       einfo ("%X%P: .gnu.hash is incompatible with the MIPS ABI\n");
  45       link_info.emit_hash = TRUE;
  46       link_info.emit_gnu_hash = FALSE;
  47     }
  48   after_parse_default ();
  49 }
  50
  51 struct hook_stub_info
  52 {
  53   lang_statement_list_type add;
  54   asection *input_section;
  55 };
  56
  57 /* Traverse the linker tree to find the spot where the stub goes.  */
  58
  59 static bfd_boolean
  60 hook_in_stub (struct hook_stub_info *info, lang_statement_union_type **lp)
  61 {
  62   lang_statement_union_type *l;
  63   bfd_boolean ret;
  64
  65   for (; (l = *lp) != NULL; lp = &l->header.next)
  66     {
  67       switch (l->header.type)
  68         {
  69         case lang_constructors_statement_enum:
  70           ret = hook_in_stub (info, &constructor_list.head);
  71           if (ret)
  72             return ret;
  73           break;
  74
  75         case lang_output_section_statement_enum:
  76           ret = hook_in_stub (info,
  77                               &l->output_section_statement.children.head);
  78           if (ret)
  79             return ret;
  80           break;
  81
  82         case lang_wild_statement_enum:
  83           ret = hook_in_stub (info, &l->wild_statement.children.head);
  84           if (ret)
  85             return ret;
  86           break;
  87
  88         case lang_group_statement_enum:
  89           ret = hook_in_stub (info, &l->group_statement.children.head);
  90           if (ret)
  91             return ret;
  92           break;
  93
  94         case lang_input_section_enum:
  95           if (info->input_section == NULL
  96               || l->input_section.section == info->input_section)
  97             {
  98               /* We've found our section.  Insert the stub immediately
  99                  before its associated input section.  */
 100               *lp = info->add.head;
 101               *(info->add.tail) = l;
 102               return TRUE;
 103             }
 104           break;
 105
 106         case lang_data_statement_enum:
 107         case lang_reloc_statement_enum:
 108         case lang_object_symbols_statement_enum:
 109         case lang_output_statement_enum:
 110         case lang_target_statement_enum:
 111         case lang_input_statement_enum:
 112         case lang_assignment_statement_enum:
 113         case lang_padding_statement_enum:
 114         case lang_address_statement_enum:
 115         case lang_fill_statement_enum:
 116           break;
 117
 118         default:
 119           FAIL ();
 120           break;
 121         }
 122     }
 123   return FALSE;
 124 }
 125
 126 /* Create a new stub section called STUB_SEC_NAME and arrange for it to
 127    be linked in OUTPUT_SECTION.  The section should go at the beginning of
 128    OUTPUT_SECTION if INPUT_SECTION is null, otherwise it must go immediately
 129    before INPUT_SECTION.  */
 130
 131 static asection *
 132 mips_add_stub_section (const char *stub_sec_name, asection *input_section,
 133                        asection *output_section)
 134 {
 135   asection *stub_sec;
 136   flagword flags;
 137   const char *secname;
 138   lang_output_section_statement_type *os;
 139   struct hook_stub_info info;
 140
 141   /* PR 12845: If the input section has been garbage collected it will
 142      not have its output section set to *ABS*.  */
 143   if (bfd_is_abs_section (output_section))
 144     return NULL;
 145
 146   /* Create the stub file, if we haven't already.  */
 147   if (stub_file == NULL)
 148     {
 149       stub_file = lang_add_input_file ("linker stubs",
 150                                        lang_input_file_is_fake_enum,
 151                                        NULL);
 152       stub_bfd = bfd_create ("linker stubs", link_info.output_bfd);
 153       if (stub_bfd == NULL
 154           || !bfd_set_arch_mach (stub_bfd,
 155                                  bfd_get_arch (link_info.output_bfd),
 156                                  bfd_get_mach (link_info.output_bfd)))
 157         {
 158           einfo ("%F%P: can not create BFD %E\n");
 159           return NULL;
 160         }
 161       stub_bfd->flags |= BFD_LINKER_CREATED;
 162       stub_file->the_bfd = stub_bfd;
 163       ldlang_add_file (stub_file);
 164     }
 165
 166   /* Create the section.  */
 167   stub_sec = bfd_make_section_anyway (stub_bfd, stub_sec_name);
 168   if (stub_sec == NULL)
 169     goto err_ret;
 170
 171   /* Set the flags.  */
 172   flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE
 173            | SEC_HAS_CONTENTS | SEC_IN_MEMORY | SEC_KEEP);
 174   if (!bfd_set_section_flags (stub_bfd, stub_sec, flags))
 175     goto err_ret;
 176
 177   /* Create an output section statement.  */
 178   secname = bfd_get_section_name (output_section->owner, output_section);
 179   os = lang_output_section_find (secname);
 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   if (is_mips_elf (link_info.output_bfd))
 203     _bfd_mips_elf_init_stubs (&link_info, mips_add_stub_section);
 204 }
 205
 206 /* This is called after we have merged the private data of the input bfds.  */
 207
 208 static void
 209 mips_before_allocation (void)
 210 {
 211   flagword flags;
 212
 213   flags = elf_elfheader (link_info.output_bfd)->e_flags;
 214   if (!link_info.shared
 215       && !link_info.nocopyreloc
 216       && (flags & (EF_MIPS_PIC | EF_MIPS_CPIC)) == EF_MIPS_CPIC)
 217     _bfd_mips_elf_use_plts_and_copy_relocs (&link_info);
 218
 219   gld${EMULATION_NAME}_before_allocation ();
 220 }
 221
 222 /* Avoid processing the fake stub_file in vercheck, stat_needed and
 223    check_needed routines.  */
 224
 225 static void (*real_func) (lang_input_statement_type *);
 226
 227 static void mips_for_each_input_file_wrapper (lang_input_statement_type *l)
 228 {
 229   if (l != stub_file)
 230     (*real_func) (l);
 231 }
 232
 233 static void
 234 mips_lang_for_each_input_file (void (*func) (lang_input_statement_type *))
 235 {
 236   real_func = func;
 237   lang_for_each_input_file (&mips_for_each_input_file_wrapper);
 238 }
 239
 240 #define lang_for_each_input_file mips_lang_for_each_input_file
 241
 242 EOF
 243
 244 LDEMUL_AFTER_PARSE=mips_after_parse
 245 LDEMUL_BEFORE_ALLOCATION=mips_before_allocation
 246 LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=mips_create_output_section_statements