1# This shell script emits a C file. -*- C -*- 2# Copyright (C) 2009-2016 Free Software Foundation, Inc. 3# Contributed by ARM Ltd. 4# 5# This file is part of the GNU Binutils. 6# 7# This program is free software; you can redistribute it and/or modify 8# it under the terms of the GNU General Public License as published by 9# the Free Software Foundation; either version 3 of the license, or 10# (at your option) any later version. 11# 12# This program is distributed in the hope that it will be useful, 13# but WITHOUT ANY WARRANTY; without even the implied warranty of 14# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15# GNU General Public License for more details. 16# 17# You should have received a copy of the GNU General Public License 18# along with this program; see the file COPYING3. If not, 19# see <http://www.gnu.org/licenses/>. 20# 21 22# This file is sourced from elf32.em, and defines extra aarch64-elf 23# specific routines. 24# 25fragment <<EOF 26 27#include "ldctor.h" 28#include "elf/aarch64.h" 29 30static int no_enum_size_warning = 0; 31static int no_wchar_size_warning = 0; 32static int pic_veneer = 0; 33static int fix_erratum_835769 = 0; 34static int fix_erratum_843419 = 0; 35static int no_apply_dynamic_relocs = 0; 36 37static void 38gld${EMULATION_NAME}_before_parse (void) 39{ 40#ifndef TARGET_ /* I.e., if not generic. */ 41 ldfile_set_output_arch ("`echo ${ARCH}`", bfd_arch_unknown); 42#endif /* not TARGET_ */ 43 input_flags.dynamic = ${DYNAMIC_LINK-TRUE}; 44 input_flags.add_DT_NEEDED_for_dynamic = TRUE; 45 config.has_shared = `if test -n "$GENERATE_SHLIB_SCRIPT" ; then echo TRUE ; else echo FALSE ; fi`; 46 config.separate_code = `if test "x${SEPARATE_CODE}" = xyes ; then echo TRUE ; else echo FALSE ; fi`; 47} 48 49static void 50aarch64_elf_before_allocation (void) 51{ 52 /* We should be able to set the size of the interworking stub section. We 53 can't do it until later if we have dynamic sections, though. */ 54 if (! elf_hash_table (&link_info)->dynamic_sections_created) 55 { 56 /* Here we rummage through the found bfds to collect information. */ 57 LANG_FOR_EACH_INPUT_STATEMENT (is) 58 { 59 /* Initialise mapping tables for code/data. */ 60 bfd_elf${ELFSIZE}_aarch64_init_maps (is->the_bfd); 61 } 62 } 63 64 /* Call the standard elf routine. */ 65 gld${EMULATION_NAME}_before_allocation (); 66} 67 68/* Fake input file for stubs. */ 69static lang_input_statement_type *stub_file; 70 71/* Whether we need to call gldarm_layout_sections_again. */ 72static int need_laying_out = 0; 73 74/* Maximum size of a group of input sections that can be handled by 75 one stub section. A value of +/-1 indicates the bfd back-end 76 should use a suitable default size. */ 77static bfd_signed_vma group_size = 1; 78 79struct hook_stub_info 80{ 81 lang_statement_list_type add; 82 asection *input_section; 83}; 84 85/* Traverse the linker tree to find the spot where the stub goes. */ 86 87static bfd_boolean 88hook_in_stub (struct hook_stub_info *info, lang_statement_union_type **lp) 89{ 90 lang_statement_union_type *l; 91 bfd_boolean ret; 92 93 for (; (l = *lp) != NULL; lp = &l->header.next) 94 { 95 switch (l->header.type) 96 { 97 case lang_constructors_statement_enum: 98 ret = hook_in_stub (info, &constructor_list.head); 99 if (ret) 100 return ret; 101 break; 102 103 case lang_output_section_statement_enum: 104 ret = hook_in_stub (info, 105 &l->output_section_statement.children.head); 106 if (ret) 107 return ret; 108 break; 109 110 case lang_wild_statement_enum: 111 ret = hook_in_stub (info, &l->wild_statement.children.head); 112 if (ret) 113 return ret; 114 break; 115 116 case lang_group_statement_enum: 117 ret = hook_in_stub (info, &l->group_statement.children.head); 118 if (ret) 119 return ret; 120 break; 121 122 case lang_input_section_enum: 123 if (l->input_section.section == info->input_section) 124 { 125 /* We've found our section. Insert the stub immediately 126 after its associated input section. */ 127 *(info->add.tail) = l->header.next; 128 l->header.next = info->add.head; 129 return TRUE; 130 } 131 break; 132 133 case lang_data_statement_enum: 134 case lang_reloc_statement_enum: 135 case lang_object_symbols_statement_enum: 136 case lang_output_statement_enum: 137 case lang_target_statement_enum: 138 case lang_input_statement_enum: 139 case lang_assignment_statement_enum: 140 case lang_padding_statement_enum: 141 case lang_address_statement_enum: 142 case lang_fill_statement_enum: 143 break; 144 145 default: 146 FAIL (); 147 break; 148 } 149 } 150 return FALSE; 151} 152 153 154/* Call-back for elf${ELFSIZE}_aarch64_size_stubs. */ 155 156/* Create a new stub section, and arrange for it to be linked 157 immediately after INPUT_SECTION. */ 158 159static asection * 160elf${ELFSIZE}_aarch64_add_stub_section (const char *stub_sec_name, 161 asection *input_section) 162{ 163 asection *stub_sec; 164 flagword flags; 165 asection *output_section; 166 lang_output_section_statement_type *os; 167 struct hook_stub_info info; 168 169 flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE 170 | SEC_HAS_CONTENTS | SEC_RELOC | SEC_IN_MEMORY | SEC_KEEP); 171 stub_sec = bfd_make_section_anyway_with_flags (stub_file->the_bfd, 172 stub_sec_name, flags); 173 if (stub_sec == NULL) 174 goto err_ret; 175 176 bfd_set_section_alignment (stub_file->the_bfd, stub_sec, 2); 177 178 output_section = input_section->output_section; 179 os = lang_output_section_get (output_section); 180 181 info.input_section = input_section; 182 lang_list_init (&info.add); 183 lang_add_section (&info.add, stub_sec, NULL, os); 184 185 if (info.add.head == NULL) 186 goto err_ret; 187 188 if (hook_in_stub (&info, &os->children.head)) 189 return stub_sec; 190 191 err_ret: 192 einfo ("%X%P: can not make stub section: %E\n"); 193 return NULL; 194} 195 196/* Another call-back for elf${ELFSIZE}_aarch64_size_stubs. */ 197 198static void 199gldaarch64_layout_sections_again (void) 200{ 201 /* If we have changed sizes of the stub sections, then we need 202 to recalculate all the section offsets. This may mean we need to 203 add even more stubs. */ 204 gld${EMULATION_NAME}_map_segments (TRUE); 205 need_laying_out = -1; 206} 207 208static void 209build_section_lists (lang_statement_union_type *statement) 210{ 211 if (statement->header.type == lang_input_section_enum) 212 { 213 asection *i = statement->input_section.section; 214 215 if (!((lang_input_statement_type *) i->owner->usrdata)->flags.just_syms 216 && (i->flags & SEC_EXCLUDE) == 0 217 && i->output_section != NULL 218 && i->output_section->owner == link_info.output_bfd) 219 elf${ELFSIZE}_aarch64_next_input_section (& link_info, i); 220 } 221} 222 223static void 224gld${EMULATION_NAME}_after_allocation (void) 225{ 226 int ret; 227 228 /* bfd_elf32_discard_info just plays with debugging sections, 229 ie. doesn't affect any code, so we can delay resizing the 230 sections. It's likely we'll resize everything in the process of 231 adding stubs. */ 232 ret = bfd_elf_discard_info (link_info.output_bfd, & link_info); 233 if (ret < 0) 234 { 235 einfo ("%X%P: .eh_frame/.stab edit: %E\n"); 236 return; 237 } 238 else if (ret > 0) 239 need_laying_out = 1; 240 241 /* If generating a relocatable output file, then we don't 242 have to examine the relocs. */ 243 if (stub_file != NULL && !bfd_link_relocatable (&link_info)) 244 { 245 ret = elf${ELFSIZE}_aarch64_setup_section_lists (link_info.output_bfd, 246 &link_info); 247 if (ret != 0) 248 { 249 if (ret < 0) 250 { 251 einfo ("%X%P: could not compute sections lists for stub generation: %E\n"); 252 return; 253 } 254 255 lang_for_each_statement (build_section_lists); 256 257 /* Call into the BFD backend to do the real work. */ 258 if (! elf${ELFSIZE}_aarch64_size_stubs (link_info.output_bfd, 259 stub_file->the_bfd, 260 & link_info, 261 group_size, 262 & elf${ELFSIZE}_aarch64_add_stub_section, 263 & gldaarch64_layout_sections_again)) 264 { 265 einfo ("%X%P: cannot size stub section: %E\n"); 266 return; 267 } 268 } 269 } 270 271 if (need_laying_out != -1) 272 gld${EMULATION_NAME}_map_segments (need_laying_out); 273} 274 275static void 276gld${EMULATION_NAME}_finish (void) 277{ 278 if (!bfd_link_relocatable (&link_info)) 279 { 280 /* Now build the linker stubs. */ 281 if (stub_file->the_bfd->sections != NULL) 282 { 283 if (! elf${ELFSIZE}_aarch64_build_stubs (& link_info)) 284 einfo ("%X%P: can not build stubs: %E\n"); 285 } 286 } 287 288 finish_default (); 289} 290 291/* This is a convenient point to tell BFD about target specific flags. 292 After the output has been created, but before inputs are read. */ 293static void 294aarch64_elf_create_output_section_statements (void) 295{ 296 if (strstr (bfd_get_target (link_info.output_bfd), "aarch64") == NULL) 297 { 298 /* The arm backend needs special fields in the output hash structure. 299 These will only be created if the output format is an arm format, 300 hence we do not support linking and changing output formats at the 301 same time. Use a link followed by objcopy to change output formats. */ 302 einfo ("%F%X%P: error: Cannot change output format whilst linking AArch64 binaries.\n"); 303 return; 304 } 305 306 bfd_elf${ELFSIZE}_aarch64_set_options (link_info.output_bfd, &link_info, 307 no_enum_size_warning, 308 no_wchar_size_warning, 309 pic_veneer, 310 fix_erratum_835769, fix_erratum_843419, 311 no_apply_dynamic_relocs); 312 313 stub_file = lang_add_input_file ("linker stubs", 314 lang_input_file_is_fake_enum, 315 NULL); 316 stub_file->the_bfd = bfd_create ("linker stubs", link_info.output_bfd); 317 if (stub_file->the_bfd == NULL 318 || ! bfd_set_arch_mach (stub_file->the_bfd, 319 bfd_get_arch (link_info.output_bfd), 320 bfd_get_mach (link_info.output_bfd))) 321 { 322 einfo ("%X%P: can not create BFD %E\n"); 323 return; 324 } 325 326 stub_file->the_bfd->flags |= BFD_LINKER_CREATED; 327 ldlang_add_file (stub_file); 328} 329 330/* Avoid processing the fake stub_file in vercheck, stat_needed and 331 check_needed routines. */ 332 333static void (*real_func) (lang_input_statement_type *); 334 335static void aarch64_for_each_input_file_wrapper (lang_input_statement_type *l) 336{ 337 if (l != stub_file) 338 (*real_func) (l); 339} 340 341static void 342aarch64_lang_for_each_input_file (void (*func) (lang_input_statement_type *)) 343{ 344 real_func = func; 345 lang_for_each_input_file (&aarch64_for_each_input_file_wrapper); 346} 347 348#define lang_for_each_input_file aarch64_lang_for_each_input_file 349 350EOF 351 352# Define some shell vars to insert bits of code into the standard elf 353# parse_args and list_options functions. 354# 355PARSE_AND_LIST_PROLOGUE=' 356#define OPTION_NO_ENUM_SIZE_WARNING 309 357#define OPTION_PIC_VENEER 310 358#define OPTION_STUBGROUP_SIZE 311 359#define OPTION_NO_WCHAR_SIZE_WARNING 312 360#define OPTION_FIX_ERRATUM_835769 313 361#define OPTION_FIX_ERRATUM_843419 314 362#define OPTION_NO_APPLY_DYNAMIC_RELOCS 315 363' 364 365PARSE_AND_LIST_SHORTOPTS=p 366 367PARSE_AND_LIST_LONGOPTS=' 368 { "no-pipeline-knowledge", no_argument, NULL, '\'p\''}, 369 { "no-enum-size-warning", no_argument, NULL, OPTION_NO_ENUM_SIZE_WARNING}, 370 { "pic-veneer", no_argument, NULL, OPTION_PIC_VENEER}, 371 { "stub-group-size", required_argument, NULL, OPTION_STUBGROUP_SIZE }, 372 { "no-wchar-size-warning", no_argument, NULL, OPTION_NO_WCHAR_SIZE_WARNING}, 373 { "fix-cortex-a53-835769", no_argument, NULL, OPTION_FIX_ERRATUM_835769}, 374 { "fix-cortex-a53-843419", no_argument, NULL, OPTION_FIX_ERRATUM_843419}, 375 { "no-apply-dynamic-relocs", no_argument, NULL, OPTION_NO_APPLY_DYNAMIC_RELOCS}, 376' 377 378PARSE_AND_LIST_OPTIONS=' 379 fprintf (file, _(" --no-enum-size-warning Don'\''t warn about objects with incompatible\n" 380 " enum sizes\n")); 381 fprintf (file, _(" --no-wchar-size-warning Don'\''t warn about objects with incompatible" 382 " wchar_t sizes\n")); 383 fprintf (file, _(" --pic-veneer Always generate PIC interworking veneers\n")); 384 fprintf (file, _("\ 385 --stub-group-size=N Maximum size of a group of input sections that can be\n\ 386 handled by one stub section. A negative value\n\ 387 locates all stubs after their branches (with a\n\ 388 group size of -N), while a positive value allows\n\ 389 two groups of input sections, one before, and one\n\ 390 after each stub section. Values of +/-1 indicate\n\ 391 the linker should choose suitable defaults.\n" 392 )); 393 fprintf (file, _(" --fix-cortex-a53-835769 Fix erratum 835769\n")); 394 fprintf (file, _(" --fix-cortex-a53-843419 Fix erratum 843419\n")); 395 fprintf (file, _(" --no-apply-dynamic-relocs Do not apply link-time values for dynamic relocations\n")); 396' 397 398PARSE_AND_LIST_ARGS_CASES=' 399 case '\'p\'': 400 /* Only here for backwards compatibility. */ 401 break; 402 403 case OPTION_NO_ENUM_SIZE_WARNING: 404 no_enum_size_warning = 1; 405 break; 406 407 case OPTION_NO_WCHAR_SIZE_WARNING: 408 no_wchar_size_warning = 1; 409 break; 410 411 case OPTION_PIC_VENEER: 412 pic_veneer = 1; 413 break; 414 415 case OPTION_FIX_ERRATUM_835769: 416 fix_erratum_835769 = 1; 417 break; 418 419 case OPTION_FIX_ERRATUM_843419: 420 fix_erratum_843419 = 1; 421 break; 422 423 case OPTION_NO_APPLY_DYNAMIC_RELOCS: 424 no_apply_dynamic_relocs = 1; 425 break; 426 427 case OPTION_STUBGROUP_SIZE: 428 { 429 const char *end; 430 431 group_size = bfd_scan_vma (optarg, &end, 0); 432 if (*end) 433 einfo (_("%P%F: invalid number `%s'\''\n"), optarg); 434 } 435 break; 436' 437 438# We have our own before_allocation etc. functions, but they call 439# the standard routines, so give them a different name. 440LDEMUL_BEFORE_ALLOCATION=aarch64_elf_before_allocation 441LDEMUL_AFTER_ALLOCATION=gld${EMULATION_NAME}_after_allocation 442LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=aarch64_elf_create_output_section_statements 443 444# Replace the elf before_parse function with our own. 445LDEMUL_BEFORE_PARSE=gld"${EMULATION_NAME}"_before_parse 446 447# Call the extra arm-elf function 448LDEMUL_FINISH=gld${EMULATION_NAME}_finish 449