1# This shell script emits a C file. -*- C -*- 2# Copyright (C) 2009-2014 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; 35 36static void 37gld${EMULATION_NAME}_before_parse (void) 38{ 39#ifndef TARGET_ /* I.e., if not generic. */ 40 ldfile_set_output_arch ("`echo ${ARCH}`", bfd_arch_unknown); 41#endif /* not TARGET_ */ 42 input_flags.dynamic = ${DYNAMIC_LINK-TRUE}; 43 config.has_shared = `if test -n "$GENERATE_SHLIB_SCRIPT" ; then echo TRUE ; else echo FALSE ; fi`; 44 config.separate_code = `if test "x${SEPARATE_CODE}" = xyes ; then echo TRUE ; else echo FALSE ; fi`; 45} 46 47static void 48aarch64_elf_before_allocation (void) 49{ 50 /* We should be able to set the size of the interworking stub section. We 51 can't do it until later if we have dynamic sections, though. */ 52 if (! elf_hash_table (&link_info)->dynamic_sections_created) 53 { 54 /* Here we rummage through the found bfds to collect information. */ 55 LANG_FOR_EACH_INPUT_STATEMENT (is) 56 { 57 /* Initialise mapping tables for code/data. */ 58 bfd_elf${ELFSIZE}_aarch64_init_maps (is->the_bfd); 59 } 60 } 61 62 /* Call the standard elf routine. */ 63 gld${EMULATION_NAME}_before_allocation (); 64} 65 66/* Fake input file for stubs. */ 67static lang_input_statement_type *stub_file; 68 69/* Whether we need to call gldarm_layout_sections_again. */ 70static int need_laying_out = 0; 71 72/* Maximum size of a group of input sections that can be handled by 73 one stub section. A value of +/-1 indicates the bfd back-end 74 should use a suitable default size. */ 75static bfd_signed_vma group_size = 1; 76 77struct hook_stub_info 78{ 79 lang_statement_list_type add; 80 asection *input_section; 81}; 82 83/* Traverse the linker tree to find the spot where the stub goes. */ 84 85static bfd_boolean 86hook_in_stub (struct hook_stub_info *info, lang_statement_union_type **lp) 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); 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 if (ret) 105 return ret; 106 break; 107 108 case lang_wild_statement_enum: 109 ret = hook_in_stub (info, &l->wild_statement.children.head); 110 if (ret) 111 return ret; 112 break; 113 114 case lang_group_statement_enum: 115 ret = hook_in_stub (info, &l->group_statement.children.head); 116 if (ret) 117 return ret; 118 break; 119 120 case lang_input_section_enum: 121 if (l->input_section.section == info->input_section) 122 { 123 /* We've found our section. Insert the stub immediately 124 after its associated input section. */ 125 *(info->add.tail) = l->header.next; 126 l->header.next = info->add.head; 127 return TRUE; 128 } 129 break; 130 131 case lang_data_statement_enum: 132 case lang_reloc_statement_enum: 133 case lang_object_symbols_statement_enum: 134 case lang_output_statement_enum: 135 case lang_target_statement_enum: 136 case lang_input_statement_enum: 137 case lang_assignment_statement_enum: 138 case lang_padding_statement_enum: 139 case lang_address_statement_enum: 140 case lang_fill_statement_enum: 141 break; 142 143 default: 144 FAIL (); 145 break; 146 } 147 } 148 return FALSE; 149} 150 151 152/* Call-back for elf${ELFSIZE}_aarch64_size_stubs. */ 153 154/* Create a new stub section, and arrange for it to be linked 155 immediately after INPUT_SECTION. */ 156 157static asection * 158elf${ELFSIZE}_aarch64_add_stub_section (const char *stub_sec_name, 159 asection *input_section) 160{ 161 asection *stub_sec; 162 flagword flags; 163 asection *output_section; 164 lang_output_section_statement_type *os; 165 struct hook_stub_info info; 166 167 flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE 168 | SEC_HAS_CONTENTS | SEC_RELOC | SEC_IN_MEMORY | SEC_KEEP); 169 stub_sec = bfd_make_section_anyway_with_flags (stub_file->the_bfd, 170 stub_sec_name, flags); 171 if (stub_sec == NULL) 172 goto err_ret; 173 174 bfd_set_section_alignment (stub_file->the_bfd, stub_sec, 2); 175 176 output_section = input_section->output_section; 177 os = lang_output_section_get (output_section); 178 179 info.input_section = input_section; 180 lang_list_init (&info.add); 181 lang_add_section (&info.add, stub_sec, NULL, os); 182 183 if (info.add.head == NULL) 184 goto err_ret; 185 186 if (hook_in_stub (&info, &os->children.head)) 187 return stub_sec; 188 189 err_ret: 190 einfo ("%X%P: can not make stub section: %E\n"); 191 return NULL; 192} 193 194/* Another call-back for elf${ELFSIZE}_aarch64_size_stubs. */ 195 196static void 197gldaarch64_layout_sections_again (void) 198{ 199 /* If we have changed sizes of the stub sections, then we need 200 to recalculate all the section offsets. This may mean we need to 201 add even more stubs. */ 202 gld${EMULATION_NAME}_map_segments (TRUE); 203 need_laying_out = -1; 204} 205 206static void 207build_section_lists (lang_statement_union_type *statement) 208{ 209 if (statement->header.type == lang_input_section_enum) 210 { 211 asection *i = statement->input_section.section; 212 213 if (!((lang_input_statement_type *) i->owner->usrdata)->flags.just_syms 214 && (i->flags & SEC_EXCLUDE) == 0 215 && i->output_section != NULL 216 && i->output_section->owner == link_info.output_bfd) 217 elf${ELFSIZE}_aarch64_next_input_section (& link_info, i); 218 } 219} 220 221static void 222gld${EMULATION_NAME}_after_allocation (void) 223{ 224 int ret; 225 226 /* bfd_elf32_discard_info just plays with debugging sections, 227 ie. doesn't affect any code, so we can delay resizing the 228 sections. It's likely we'll resize everything in the process of 229 adding stubs. */ 230 ret = bfd_elf_discard_info (link_info.output_bfd, & link_info); 231 if (ret < 0) 232 { 233 einfo ("%X%P: .eh_frame/.stab edit: %E\n"); 234 return; 235 } 236 else if (ret > 0) 237 need_laying_out = 1; 238 239 /* If generating a relocatable output file, then we don't 240 have to examine the relocs. */ 241 if (stub_file != NULL && !link_info.relocatable) 242 { 243 ret = elf${ELFSIZE}_aarch64_setup_section_lists (link_info.output_bfd, 244 &link_info); 245 if (ret != 0) 246 { 247 if (ret < 0) 248 { 249 einfo ("%X%P: could not compute sections lists for stub generation: %E\n"); 250 return; 251 } 252 253 lang_for_each_statement (build_section_lists); 254 255 /* Call into the BFD backend to do the real work. */ 256 if (! elf${ELFSIZE}_aarch64_size_stubs (link_info.output_bfd, 257 stub_file->the_bfd, 258 & link_info, 259 group_size, 260 & elf${ELFSIZE}_aarch64_add_stub_section, 261 & gldaarch64_layout_sections_again)) 262 { 263 einfo ("%X%P: cannot size stub section: %E\n"); 264 return; 265 } 266 } 267 } 268 269 if (need_laying_out != -1) 270 gld${EMULATION_NAME}_map_segments (need_laying_out); 271} 272 273static void 274gld${EMULATION_NAME}_finish (void) 275{ 276 if (! link_info.relocatable) 277 { 278 /* Now build the linker stubs. */ 279 if (stub_file->the_bfd->sections != NULL) 280 { 281 if (! elf${ELFSIZE}_aarch64_build_stubs (& link_info)) 282 einfo ("%X%P: can not build stubs: %E\n"); 283 } 284 } 285 286 finish_default (); 287} 288 289/* This is a convenient point to tell BFD about target specific flags. 290 After the output has been created, but before inputs are read. */ 291static void 292aarch64_elf_create_output_section_statements (void) 293{ 294 if (strstr (bfd_get_target (link_info.output_bfd), "aarch64") == NULL) 295 { 296 /* The arm backend needs special fields in the output hash structure. 297 These will only be created if the output format is an arm format, 298 hence we do not support linking and changing output formats at the 299 same time. Use a link followed by objcopy to change output formats. */ 300 einfo ("%F%X%P: error: Cannot change output format whilst linking AArch64 binaries.\n"); 301 return; 302 } 303 304 bfd_elf${ELFSIZE}_aarch64_set_options (link_info.output_bfd, &link_info, 305 no_enum_size_warning, 306 no_wchar_size_warning, 307 pic_veneer, 308 fix_erratum_835769, fix_erratum_843419); 309 310 stub_file = lang_add_input_file ("linker stubs", 311 lang_input_file_is_fake_enum, 312 NULL); 313 stub_file->the_bfd = bfd_create ("linker stubs", link_info.output_bfd); 314 if (stub_file->the_bfd == NULL 315 || ! bfd_set_arch_mach (stub_file->the_bfd, 316 bfd_get_arch (link_info.output_bfd), 317 bfd_get_mach (link_info.output_bfd))) 318 { 319 einfo ("%X%P: can not create BFD %E\n"); 320 return; 321 } 322 323 stub_file->the_bfd->flags |= BFD_LINKER_CREATED; 324 ldlang_add_file (stub_file); 325} 326 327/* Avoid processing the fake stub_file in vercheck, stat_needed and 328 check_needed routines. */ 329 330static void (*real_func) (lang_input_statement_type *); 331 332static void aarch64_for_each_input_file_wrapper (lang_input_statement_type *l) 333{ 334 if (l != stub_file) 335 (*real_func) (l); 336} 337 338static void 339aarch64_lang_for_each_input_file (void (*func) (lang_input_statement_type *)) 340{ 341 real_func = func; 342 lang_for_each_input_file (&aarch64_for_each_input_file_wrapper); 343} 344 345#define lang_for_each_input_file aarch64_lang_for_each_input_file 346 347EOF 348 349# Define some shell vars to insert bits of code into the standard elf 350# parse_args and list_options functions. 351# 352PARSE_AND_LIST_PROLOGUE=' 353#define OPTION_NO_ENUM_SIZE_WARNING 309 354#define OPTION_PIC_VENEER 310 355#define OPTION_STUBGROUP_SIZE 311 356#define OPTION_NO_WCHAR_SIZE_WARNING 312 357#define OPTION_FIX_ERRATUM_835769 313 358#define OPTION_FIX_ERRATUM_843419 314 359' 360 361PARSE_AND_LIST_SHORTOPTS=p 362 363PARSE_AND_LIST_LONGOPTS=' 364 { "no-pipeline-knowledge", no_argument, NULL, '\'p\''}, 365 { "no-enum-size-warning", no_argument, NULL, OPTION_NO_ENUM_SIZE_WARNING}, 366 { "pic-veneer", no_argument, NULL, OPTION_PIC_VENEER}, 367 { "stub-group-size", required_argument, NULL, OPTION_STUBGROUP_SIZE }, 368 { "no-wchar-size-warning", no_argument, NULL, OPTION_NO_WCHAR_SIZE_WARNING}, 369 { "fix-cortex-a53-835769", no_argument, NULL, OPTION_FIX_ERRATUM_835769}, 370 { "fix-cortex-a53-843419", no_argument, NULL, OPTION_FIX_ERRATUM_843419}, 371' 372 373PARSE_AND_LIST_OPTIONS=' 374 fprintf (file, _(" --no-enum-size-warning Don'\''t warn about objects with incompatible\n" 375 " enum sizes\n")); 376 fprintf (file, _(" --no-wchar-size-warning Don'\''t warn about objects with incompatible" 377 " wchar_t sizes\n")); 378 fprintf (file, _(" --pic-veneer Always generate PIC interworking veneers\n")); 379 fprintf (file, _("\ 380 --stub-group-size=N Maximum size of a group of input sections that can be\n\ 381 handled by one stub section. A negative value\n\ 382 locates all stubs after their branches (with a\n\ 383 group size of -N), while a positive value allows\n\ 384 two groups of input sections, one before, and one\n\ 385 after each stub section. Values of +/-1 indicate\n\ 386 the linker should choose suitable defaults.\n" 387 )); 388 fprintf (file, _(" --fix-cortex-a53-835769 Fix erratum 835769\n")); 389 fprintf (file, _(" --fix-cortex-a53-843419 Fix erratum 843419\n")); 390' 391 392PARSE_AND_LIST_ARGS_CASES=' 393 case '\'p\'': 394 /* Only here for backwards compatibility. */ 395 break; 396 397 case OPTION_NO_ENUM_SIZE_WARNING: 398 no_enum_size_warning = 1; 399 break; 400 401 case OPTION_NO_WCHAR_SIZE_WARNING: 402 no_wchar_size_warning = 1; 403 break; 404 405 case OPTION_PIC_VENEER: 406 pic_veneer = 1; 407 break; 408 409 case OPTION_FIX_ERRATUM_835769: 410 fix_erratum_835769 = 1; 411 break; 412 413 case OPTION_FIX_ERRATUM_843419: 414 fix_erratum_843419 = 1; 415 break; 416 417 case OPTION_STUBGROUP_SIZE: 418 { 419 const char *end; 420 421 group_size = bfd_scan_vma (optarg, &end, 0); 422 if (*end) 423 einfo (_("%P%F: invalid number `%s'\''\n"), optarg); 424 } 425 break; 426' 427 428# We have our own before_allocation etc. functions, but they call 429# the standard routines, so give them a different name. 430LDEMUL_BEFORE_ALLOCATION=aarch64_elf_before_allocation 431LDEMUL_AFTER_ALLOCATION=gld${EMULATION_NAME}_after_allocation 432LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=aarch64_elf_create_output_section_statements 433 434# Replace the elf before_parse function with our own. 435LDEMUL_BEFORE_PARSE=gld"${EMULATION_NAME}"_before_parse 436 437# Call the extra arm-elf function 438LDEMUL_FINISH=gld${EMULATION_NAME}_finish 439