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