ld/emultempl/mipself.em

   1 # This shell script emits a C file. -*- C -*-
   2 #   Copyright (C) 2004-2021 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 case ${target} in
  22   *-*-*gnu*)
  23     gnu_target=TRUE
  24     ;;
  25   *)
  26     gnu_target=FALSE
  27     ;;
  28 esac
  29
  30 fragment <<EOF
  31
  32 #include "ldctor.h"
  33 #include "elf/mips.h"
  34 #include "elfxx-mips.h"
  35
  36 #define is_mips_elf(bfd)                                \
  37   (bfd_get_flavour (bfd) == bfd_target_elf_flavour      \
  38    && elf_tdata (bfd) != NULL                           \
  39    && elf_object_id (bfd) == MIPS_ELF_DATA)
  40
  41 /* Fake input file for stubs.  */
  42 static lang_input_statement_type *stub_file;
  43 static bfd *stub_bfd;
  44
  45 static bfd_boolean insn32;
  46 static bfd_boolean ignore_branch_isa;
  47 static bfd_boolean compact_branches;
  48
  49 struct hook_stub_info
  50 {
  51   lang_statement_list_type add;
  52   asection *input_section;
  53 };
  54
  55 /* Traverse the linker tree to find the spot where the stub goes.  */
  56
  57 static bfd_boolean
  58 hook_in_stub (struct hook_stub_info *info, lang_statement_union_type **lp)
  59 {
  60   lang_statement_union_type *l;
  61   bfd_boolean ret;
  62
  63   for (; (l = *lp) != NULL; lp = &l->header.next)
  64     {
  65       switch (l->header.type)
  66         {
  67         case lang_constructors_statement_enum:
  68           ret = hook_in_stub (info, &constructor_list.head);
  69           if (ret)
  70             return ret;
  71           break;
  72
  73         case lang_output_section_statement_enum:
  74           ret = hook_in_stub (info,
  75                               &l->output_section_statement.children.head);
  76           if (ret)
  77             return ret;
  78           break;
  79
  80         case lang_wild_statement_enum:
  81           ret = hook_in_stub (info, &l->wild_statement.children.head);
  82           if (ret)
  83             return ret;
  84           break;
  85
  86         case lang_group_statement_enum:
  87           ret = hook_in_stub (info, &l->group_statement.children.head);
  88           if (ret)
  89             return ret;
  90           break;
  91
  92         case lang_input_section_enum:
  93           if (info->input_section == NULL
  94               || l->input_section.section == info->input_section)
  95             {
  96               /* We've found our section.  Insert the stub immediately
  97                  before its associated input section.  */
  98               *lp = info->add.head;
  99               *(info->add.tail) = l;
 100               return TRUE;
 101             }
 102           break;
 103
 104         case lang_data_statement_enum:
 105         case lang_reloc_statement_enum:
 106         case lang_object_symbols_statement_enum:
 107         case lang_output_statement_enum:
 108         case lang_target_statement_enum:
 109         case lang_input_statement_enum:
 110         case lang_assignment_statement_enum:
 111         case lang_padding_statement_enum:
 112         case lang_address_statement_enum:
 113         case lang_fill_statement_enum:
 114           break;
 115
 116         default:
 117           FAIL ();
 118           break;
 119         }
 120     }
 121   return FALSE;
 122 }
 123
 124 /* Create a new stub section called STUB_SEC_NAME and arrange for it to
 125    be linked in OUTPUT_SECTION.  The section should go at the beginning of
 126    OUTPUT_SECTION if INPUT_SECTION is null, otherwise it must go immediately
 127    before INPUT_SECTION.  */
 128
 129 static asection *
 130 mips_add_stub_section (const char *stub_sec_name, asection *input_section,
 131                        asection *output_section)
 132 {
 133   asection *stub_sec;
 134   flagword flags;
 135   lang_output_section_statement_type *os;
 136   struct hook_stub_info info;
 137
 138   /* PR 12845: If the input section has been garbage collected it will
 139      not have its output section set to *ABS*.  */
 140   if (bfd_is_abs_section (output_section))
 141     return NULL;
 142
 143   /* Create the stub file, if we haven't already.  */
 144   if (stub_file == NULL)
 145     {
 146       stub_file = lang_add_input_file ("linker stubs",
 147                                        lang_input_file_is_fake_enum,
 148                                        NULL);
 149       stub_bfd = bfd_create ("linker stubs", link_info.output_bfd);
 150       if (stub_bfd == NULL
 151           || !bfd_set_arch_mach (stub_bfd,
 152                                  bfd_get_arch (link_info.output_bfd),
 153                                  bfd_get_mach (link_info.output_bfd)))
 154         {
 155           einfo (_("%F%P: can not create BFD: %E\n"));
 156           return NULL;
 157         }
 158       stub_bfd->flags |= BFD_LINKER_CREATED;
 159       stub_file->the_bfd = stub_bfd;
 160       ldlang_add_file (stub_file);
 161     }
 162
 163   /* Create the section.  */
 164   stub_sec = bfd_make_section_anyway (stub_bfd, stub_sec_name);
 165   if (stub_sec == NULL)
 166     goto err_ret;
 167
 168   /* Set the flags.  */
 169   flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE
 170            | SEC_HAS_CONTENTS | SEC_IN_MEMORY | SEC_KEEP);
 171   if (!bfd_set_section_flags (stub_sec, flags))
 172     goto err_ret;
 173
 174   os = lang_output_section_get (output_section);
 175
 176   /* Initialize a statement list that contains only the new statement.  */
 177   lang_list_init (&info.add);
 178   lang_add_section (&info.add, stub_sec, NULL, os);
 179   if (info.add.head == NULL)
 180     goto err_ret;
 181
 182   /* Insert the new statement in the appropriate place.  */
 183   info.input_section = input_section;
 184   if (hook_in_stub (&info, &os->children.head))
 185     return stub_sec;
 186
 187  err_ret:
 188   einfo (_("%X%P: can not make stub section: %E\n"));
 189   return NULL;
 190 }
 191
 192 /* This is called before the input files are opened.  */
 193
 194 static void
 195 mips_create_output_section_statements (void)
 196 {
 197   struct elf_link_hash_table *htab;
 198
 199   htab = elf_hash_table (&link_info);
 200   if (is_elf_hash_table (htab) && is_mips_elf (link_info.output_bfd))
 201     _bfd_mips_elf_linker_flags (&link_info, insn32, ignore_branch_isa,
 202                                 ${gnu_target});
 203
 204   if (is_mips_elf (link_info.output_bfd))
 205     {
 206       _bfd_mips_elf_compact_branches (&link_info, compact_branches);
 207       _bfd_mips_elf_init_stubs (&link_info, mips_add_stub_section);
 208     }
 209 }
 210
 211 /* This is called after we have merged the private data of the input bfds.  */
 212
 213 static void
 214 mips_before_allocation (void)
 215 {
 216   if (is_mips_elf (link_info.output_bfd))
 217     {
 218       flagword flags;
 219
 220       flags = elf_elfheader (link_info.output_bfd)->e_flags;
 221       if (!bfd_link_pic (&link_info)
 222           && !link_info.nocopyreloc
 223           && (flags & (EF_MIPS_PIC | EF_MIPS_CPIC)) == EF_MIPS_CPIC)
 224         _bfd_mips_elf_use_plts_and_copy_relocs (&link_info);
 225     }
 226
 227   gld${EMULATION_NAME}_before_allocation ();
 228 }
 229
 230 EOF
 231
 232 # Define some shell vars to insert bits of code into the standard elf
 233 # parse_args and list_options functions.
 234 #
 235 PARSE_AND_LIST_PROLOGUE='
 236 enum
 237   {
 238     OPTION_INSN32 = 301,
 239     OPTION_NO_INSN32,
 240     OPTION_IGNORE_BRANCH_ISA,
 241     OPTION_NO_IGNORE_BRANCH_ISA,
 242     OPTION_COMPACT_BRANCHES,
 243     OPTION_NO_COMPACT_BRANCHES
 244   };
 245 '
 246
 247 PARSE_AND_LIST_LONGOPTS='
 248   { "insn32", no_argument, NULL, OPTION_INSN32 },
 249   { "no-insn32", no_argument, NULL, OPTION_NO_INSN32 },
 250   { "ignore-branch-isa", no_argument, NULL, OPTION_IGNORE_BRANCH_ISA },
 251   { "no-ignore-branch-isa", no_argument, NULL, OPTION_NO_IGNORE_BRANCH_ISA },
 252   { "compact-branches", no_argument, NULL, OPTION_COMPACT_BRANCHES },
 253   { "no-compact-branches", no_argument, NULL, OPTION_NO_COMPACT_BRANCHES },
 254 '
 255
 256 PARSE_AND_LIST_OPTIONS='
 257   fprintf (file, _("\
 258   --insn32                    Only generate 32-bit microMIPS instructions\n"
 259                    ));
 260   fprintf (file, _("\
 261   --no-insn32                 Generate all microMIPS instructions\n"
 262                    ));
 263   fprintf (file, _("\
 264   --ignore-branch-isa         Accept invalid branch relocations requiring\n\
 265                               an ISA mode switch\n"
 266                    ));
 267   fprintf (file, _("\
 268   --no-ignore-branch-isa      Reject invalid branch relocations requiring\n\
 269                               an ISA mode switch\n"
 270                    ));
 271   fprintf (file, _("\
 272   --compact-branches          Generate compact branches/jumps for MIPS R6\n"
 273                    ));
 274   fprintf (file, _("\
 275   --no-compact-branches       Generate delay slot branches/jumps for MIPS R6\n"
 276                    ));
 277 '
 278
 279 PARSE_AND_LIST_ARGS_CASES='
 280     case OPTION_INSN32:
 281       insn32 = TRUE;
 282       break;
 283
 284     case OPTION_NO_INSN32:
 285       insn32 = FALSE;
 286       break;
 287
 288     case OPTION_IGNORE_BRANCH_ISA:
 289       ignore_branch_isa = TRUE;
 290       break;
 291
 292     case OPTION_NO_IGNORE_BRANCH_ISA:
 293       ignore_branch_isa = FALSE;
 294       break;
 295
 296     case OPTION_COMPACT_BRANCHES:
 297       compact_branches = TRUE;
 298       break;
 299
 300     case OPTION_NO_COMPACT_BRANCHES:
 301       compact_branches = FALSE;
 302       break;
 303 '
 304
 305 LDEMUL_BEFORE_ALLOCATION=mips_before_allocation
 306 LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=mips_create_output_section_statements