| 1 | # This shell script emits a C file. -*- C -*- |
| 2 | # Copyright (C) 2013-2014 Free Software Foundation, Inc. |
| 3 | # |
| 4 | # This file is part of 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 Nios II ELF |
| 23 | # specific routines. Taken from metagelf.em. |
| 24 | # |
| 25 | fragment <<EOF |
| 26 | |
| 27 | #include "ldctor.h" |
| 28 | #include "elf32-nios2.h" |
| 29 | |
| 30 | |
| 31 | /* Fake input file for stubs. */ |
| 32 | static lang_input_statement_type *stub_file; |
| 33 | |
| 34 | /* Whether we need to call nios2_layout_sections_again. */ |
| 35 | static int need_laying_out = 0; |
| 36 | |
| 37 | |
| 38 | /* This is called before the input files are opened. We create a new |
| 39 | fake input file to hold the stub sections. */ |
| 40 | |
| 41 | static void |
| 42 | nios2elf_create_output_section_statements (void) |
| 43 | { |
| 44 | extern const bfd_target bfd_elf32_littlenios2_vec, bfd_elf32_bignios2_vec; |
| 45 | |
| 46 | if (link_info.output_bfd->xvec != &bfd_elf32_littlenios2_vec |
| 47 | && link_info.output_bfd->xvec != &bfd_elf32_bignios2_vec) |
| 48 | return; |
| 49 | |
| 50 | /* If --no-relax was not explicitly specified by the user, enable |
| 51 | relaxation. If it's not enabled (either explicitly or by default), |
| 52 | we're done, as we won't need to create any stubs. */ |
| 53 | if (!link_info.relocatable && RELAXATION_DISABLED_BY_DEFAULT) |
| 54 | ENABLE_RELAXATION; |
| 55 | if (!RELAXATION_ENABLED) |
| 56 | return; |
| 57 | |
| 58 | stub_file = lang_add_input_file ("linker stubs", |
| 59 | lang_input_file_is_fake_enum, |
| 60 | NULL); |
| 61 | stub_file->the_bfd = bfd_create ("linker stubs", link_info.output_bfd); |
| 62 | if (stub_file->the_bfd == NULL |
| 63 | || ! bfd_set_arch_mach (stub_file->the_bfd, |
| 64 | bfd_get_arch (link_info.output_bfd), |
| 65 | bfd_get_mach (link_info.output_bfd))) |
| 66 | { |
| 67 | einfo ("%X%P: can not create BFD %E\n"); |
| 68 | return; |
| 69 | } |
| 70 | |
| 71 | stub_file->the_bfd->flags |= BFD_LINKER_CREATED; |
| 72 | ldlang_add_file (stub_file); |
| 73 | } |
| 74 | |
| 75 | |
| 76 | struct hook_stub_info |
| 77 | { |
| 78 | lang_statement_list_type add; |
| 79 | asection *input_section; |
| 80 | }; |
| 81 | |
| 82 | /* Traverse the linker tree to find the spot where the stub goes. */ |
| 83 | |
| 84 | static bfd_boolean |
| 85 | hook_in_stub (struct hook_stub_info *info, lang_statement_union_type **lp, |
| 86 | bfd_boolean afterp) |
| 87 | { |
| 88 | lang_statement_union_type *l; |
| 89 | bfd_boolean ret; |
| 90 | |
| 91 | for (; (l = *lp) != NULL; lp = &l->header.next) |
| 92 | { |
| 93 | switch (l->header.type) |
| 94 | { |
| 95 | case lang_constructors_statement_enum: |
| 96 | ret = hook_in_stub (info, &constructor_list.head, afterp); |
| 97 | if (ret) |
| 98 | return ret; |
| 99 | break; |
| 100 | |
| 101 | case lang_output_section_statement_enum: |
| 102 | ret = hook_in_stub (info, |
| 103 | &l->output_section_statement.children.head, |
| 104 | afterp); |
| 105 | if (ret) |
| 106 | return ret; |
| 107 | break; |
| 108 | |
| 109 | case lang_wild_statement_enum: |
| 110 | ret = hook_in_stub (info, &l->wild_statement.children.head, afterp); |
| 111 | if (ret) |
| 112 | return ret; |
| 113 | break; |
| 114 | |
| 115 | case lang_group_statement_enum: |
| 116 | ret = hook_in_stub (info, &l->group_statement.children.head, afterp); |
| 117 | if (ret) |
| 118 | return ret; |
| 119 | break; |
| 120 | |
| 121 | case lang_input_section_enum: |
| 122 | if (l->input_section.section == info->input_section) |
| 123 | { |
| 124 | /* We've found our section. Insert the stub immediately |
| 125 | before or after its associated input section. */ |
| 126 | if (afterp) |
| 127 | { |
| 128 | *(info->add.tail) = l->header.next; |
| 129 | l->header.next = info->add.head; |
| 130 | } |
| 131 | else |
| 132 | { |
| 133 | *lp = info->add.head; |
| 134 | *(info->add.tail) = l; |
| 135 | } |
| 136 | return TRUE; |
| 137 | } |
| 138 | break; |
| 139 | |
| 140 | case lang_data_statement_enum: |
| 141 | case lang_reloc_statement_enum: |
| 142 | case lang_object_symbols_statement_enum: |
| 143 | case lang_output_statement_enum: |
| 144 | case lang_target_statement_enum: |
| 145 | case lang_input_statement_enum: |
| 146 | case lang_assignment_statement_enum: |
| 147 | case lang_padding_statement_enum: |
| 148 | case lang_address_statement_enum: |
| 149 | case lang_fill_statement_enum: |
| 150 | break; |
| 151 | |
| 152 | default: |
| 153 | FAIL (); |
| 154 | break; |
| 155 | } |
| 156 | } |
| 157 | return FALSE; |
| 158 | } |
| 159 | |
| 160 | /* Call-back for elf32_nios2_size_stubs. */ |
| 161 | |
| 162 | /* Create a new stub section, and arrange for it to be linked |
| 163 | immediately before or after INPUT_SECTION, according to AFTERP. */ |
| 164 | |
| 165 | static asection * |
| 166 | nios2elf_add_stub_section (const char *stub_sec_name, asection *input_section, |
| 167 | bfd_boolean afterp) |
| 168 | { |
| 169 | asection *stub_sec; |
| 170 | flagword flags; |
| 171 | asection *output_section; |
| 172 | const char *secname; |
| 173 | lang_output_section_statement_type *os; |
| 174 | struct hook_stub_info info; |
| 175 | |
| 176 | flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE |
| 177 | | SEC_HAS_CONTENTS | SEC_RELOC | SEC_IN_MEMORY | SEC_KEEP); |
| 178 | stub_sec = bfd_make_section_anyway_with_flags (stub_file->the_bfd, |
| 179 | stub_sec_name, flags); |
| 180 | if (stub_sec == NULL) |
| 181 | goto err_ret; |
| 182 | |
| 183 | output_section = input_section->output_section; |
| 184 | secname = bfd_get_section_name (output_section->owner, output_section); |
| 185 | os = lang_output_section_find (secname); |
| 186 | |
| 187 | info.input_section = input_section; |
| 188 | lang_list_init (&info.add); |
| 189 | lang_add_section (&info.add, stub_sec, NULL, os); |
| 190 | |
| 191 | if (info.add.head == NULL) |
| 192 | goto err_ret; |
| 193 | |
| 194 | if (hook_in_stub (&info, &os->children.head, afterp)) |
| 195 | return stub_sec; |
| 196 | |
| 197 | err_ret: |
| 198 | einfo ("%X%P: can not make stub section: %E\n"); |
| 199 | return NULL; |
| 200 | } |
| 201 | |
| 202 | |
| 203 | /* Another call-back for elf32_nios2_size_stubs. */ |
| 204 | |
| 205 | static void |
| 206 | nios2elf_layout_sections_again (void) |
| 207 | { |
| 208 | /* If we have changed sizes of the stub sections, then we need |
| 209 | to recalculate all the section offsets. This may mean we need to |
| 210 | add even more stubs. */ |
| 211 | gld${EMULATION_NAME}_map_segments (TRUE); |
| 212 | need_laying_out = -1; |
| 213 | } |
| 214 | |
| 215 | |
| 216 | static void |
| 217 | build_section_lists (lang_statement_union_type *statement) |
| 218 | { |
| 219 | if (statement->header.type == lang_input_section_enum) |
| 220 | { |
| 221 | asection *i = statement->input_section.section; |
| 222 | |
| 223 | if (i->sec_info_type != SEC_INFO_TYPE_JUST_SYMS |
| 224 | && (i->flags & SEC_EXCLUDE) == 0 |
| 225 | && i->output_section != NULL |
| 226 | && i->output_section->owner == link_info.output_bfd) |
| 227 | { |
| 228 | nios2_elf32_next_input_section (&link_info, i); |
| 229 | } |
| 230 | } |
| 231 | } |
| 232 | |
| 233 | |
| 234 | /* For Nios II we use this opportunity to build linker stubs. */ |
| 235 | |
| 236 | static void |
| 237 | gld${EMULATION_NAME}_after_allocation (void) |
| 238 | { |
| 239 | /* bfd_elf_discard_info just plays with data and debugging sections, |
| 240 | ie. doesn't affect code size, so we can delay resizing the |
| 241 | sections. It's likely we'll resize everything in the process of |
| 242 | adding stubs. */ |
| 243 | if (bfd_elf_discard_info (link_info.output_bfd, &link_info)) |
| 244 | need_laying_out = 1; |
| 245 | |
| 246 | /* If generating a relocatable output file, then we don't |
| 247 | have to examine the relocs. */ |
| 248 | if (stub_file != NULL && !link_info.relocatable && RELAXATION_ENABLED) |
| 249 | { |
| 250 | int ret = nios2_elf32_setup_section_lists (link_info.output_bfd, |
| 251 | &link_info); |
| 252 | |
| 253 | if (ret != 0) |
| 254 | { |
| 255 | if (ret < 0) |
| 256 | { |
| 257 | einfo ("%X%P: can not size stub section: %E\n"); |
| 258 | return; |
| 259 | } |
| 260 | |
| 261 | lang_for_each_statement (build_section_lists); |
| 262 | |
| 263 | /* Call into the BFD backend to do the real work. */ |
| 264 | if (! nios2_elf32_size_stubs (link_info.output_bfd, |
| 265 | stub_file->the_bfd, |
| 266 | &link_info, |
| 267 | &nios2elf_add_stub_section, |
| 268 | &nios2elf_layout_sections_again)) |
| 269 | { |
| 270 | einfo ("%X%P: can not size stub section: %E\n"); |
| 271 | return; |
| 272 | } |
| 273 | } |
| 274 | } |
| 275 | |
| 276 | if (need_laying_out != -1) |
| 277 | gld${EMULATION_NAME}_map_segments (need_laying_out); |
| 278 | |
| 279 | if (!link_info.relocatable && RELAXATION_ENABLED) |
| 280 | { |
| 281 | /* Now build the linker stubs. */ |
| 282 | if (stub_file != NULL && stub_file->the_bfd->sections != NULL) |
| 283 | { |
| 284 | if (! nios2_elf32_build_stubs (&link_info)) |
| 285 | einfo ("%X%P: can not build stubs: %E\n"); |
| 286 | } |
| 287 | } |
| 288 | } |
| 289 | |
| 290 | |
| 291 | /* Avoid processing the fake stub_file in vercheck, stat_needed and |
| 292 | check_needed routines. */ |
| 293 | |
| 294 | static void (*real_func) (lang_input_statement_type *); |
| 295 | |
| 296 | static void nios2_for_each_input_file_wrapper (lang_input_statement_type *l) |
| 297 | { |
| 298 | if (l != stub_file) |
| 299 | (*real_func) (l); |
| 300 | } |
| 301 | |
| 302 | static void |
| 303 | nios2_lang_for_each_input_file (void (*func) (lang_input_statement_type *)) |
| 304 | { |
| 305 | real_func = func; |
| 306 | lang_for_each_input_file (&nios2_for_each_input_file_wrapper); |
| 307 | } |
| 308 | |
| 309 | #define lang_for_each_input_file nios2_lang_for_each_input_file |
| 310 | |
| 311 | EOF |
| 312 | |
| 313 | |
| 314 | # Put these extra nios2elf routines in ld_${EMULATION_NAME}_emulation |
| 315 | # |
| 316 | LDEMUL_AFTER_ALLOCATION=gld${EMULATION_NAME}_after_allocation |
| 317 | LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=nios2elf_create_output_section_statements |