1# This shell script emits a C file. -*- C -*- 2# Copyright (C) 2003-2020 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 22# This file is sourced from elf.em, and defines extra powerpc32-elf 23# specific routines. 24# 25fragment <<EOF 26 27#include "elf32-ppc.h" 28#include "ldlex.h" 29#include "ldlang.h" 30 31#define is_ppc_elf(bfd) \ 32 (bfd_get_flavour (bfd) == bfd_target_elf_flavour \ 33 && elf_object_id (bfd) == PPC32_ELF_DATA) 34 35/* Whether to run tls optimization. */ 36static int notlsopt = 0; 37 38/* Whether to convert inline PLT calls to direct. */ 39static int no_inline_opt = 0; 40 41/* Choose the correct place for .got. */ 42static int old_got = 0; 43 44static struct ppc_elf_params params = { PLT_UNSET, 0, -1, 45 0, 0, 0, 0, 0, 0, 0 }; 46 47static void 48ppc_after_open_output (void) 49{ 50 if (params.emit_stub_syms < 0) 51 params.emit_stub_syms = (link_info.emitrelocations 52 || bfd_link_pic (&link_info)); 53 if (params.pagesize == 0) 54 params.pagesize = config.commonpagesize; 55 ppc_elf_link_params (&link_info, ¶ms); 56} 57 58EOF 59 60# No --secure-plt, --bss-plt, or --sdata-got for vxworks. 61if test -z "$VXWORKS_BASE_EM_FILE" ; then 62 fragment <<EOF 63static void 64ppc_after_check_relocs (void) 65{ 66 if (is_ppc_elf (link_info.output_bfd)) 67 { 68 int new_plt; 69 int keep_new; 70 unsigned int num_plt; 71 unsigned int num_got; 72 lang_output_section_statement_type *os; 73 lang_output_section_statement_type *plt_os[2]; 74 lang_output_section_statement_type *got_os[2]; 75 76 new_plt = ppc_elf_select_plt_layout (link_info.output_bfd, &link_info); 77 if (new_plt < 0) 78 einfo (_("%X%P: select_plt_layout problem %E\n")); 79 80 num_got = 0; 81 num_plt = 0; 82 for (os = (void *) lang_os_list.head; 83 os != NULL; 84 os = os->next) 85 { 86 if (os->constraint == SPECIAL && strcmp (os->name, ".plt") == 0) 87 { 88 if (num_plt < 2) 89 plt_os[num_plt] = os; 90 ++num_plt; 91 } 92 if (os->constraint == SPECIAL && strcmp (os->name, ".got") == 0) 93 { 94 if (num_got < 2) 95 got_os[num_got] = os; 96 ++num_got; 97 } 98 } 99 100 keep_new = new_plt == 1 ? 0 : -1; 101 if (num_plt == 2) 102 { 103 plt_os[0]->constraint = keep_new; 104 plt_os[1]->constraint = ~keep_new; 105 } 106 if (num_got == 2) 107 { 108 if (old_got) 109 keep_new = -1; 110 got_os[0]->constraint = keep_new; 111 got_os[1]->constraint = ~keep_new; 112 } 113 } 114 115 after_check_relocs_default (); 116} 117 118EOF 119fi 120fragment <<EOF 121static void 122prelim_size_sections (void) 123{ 124 if (expld.phase != lang_mark_phase_enum) 125 { 126 expld.phase = lang_mark_phase_enum; 127 expld.dataseg.phase = exp_seg_none; 128 one_lang_size_sections_pass (NULL, FALSE); 129 /* We must not cache anything from the preliminary sizing. */ 130 lang_reset_memory_regions (); 131 } 132} 133 134static void 135ppc_before_allocation (void) 136{ 137 if (is_ppc_elf (link_info.output_bfd)) 138 { 139 if (!no_inline_opt 140 && !bfd_link_relocatable (&link_info)) 141 { 142 prelim_size_sections (); 143 144 if (!ppc_elf_inline_plt (&link_info)) 145 einfo (_("%X%P: inline PLT: %E\n")); 146 } 147 148 if (ppc_elf_tls_setup (link_info.output_bfd, &link_info) 149 && !notlsopt) 150 { 151 if (!ppc_elf_tls_optimize (link_info.output_bfd, &link_info)) 152 { 153 einfo (_("%X%P: TLS problem %E\n")); 154 return; 155 } 156 } 157 } 158 159 gld${EMULATION_NAME}_before_allocation (); 160 161 ppc_elf_maybe_strip_sdata_syms (&link_info); 162 163 if (RELAXATION_ENABLED) 164 params.branch_trampolines = 1; 165 166 /* Turn on relaxation if executable sections have addresses that 167 might make branches overflow. */ 168 else if (!RELAXATION_DISABLED_BY_USER) 169 { 170 bfd_vma low = (bfd_vma) -1; 171 bfd_vma high = 0; 172 asection *o; 173 174 /* Run lang_size_sections even if already done, so as to pick 175 up gld${EMULATION_NAME}_before_allocation sizing. This 176 matters when we have an executable bss plt which will 177 typically be laid out near the end of the image, ie. worst 178 case for branches at the start of .text. */ 179 expld.phase = lang_first_phase_enum; 180 prelim_size_sections (); 181 182 for (o = link_info.output_bfd->sections; o != NULL; o = o->next) 183 { 184 if ((o->flags & (SEC_ALLOC | SEC_CODE)) != (SEC_ALLOC | SEC_CODE)) 185 continue; 186 if (o->rawsize == 0) 187 continue; 188 if (low > o->vma) 189 low = o->vma; 190 if (high < o->vma + o->rawsize - 1) 191 high = o->vma + o->rawsize - 1; 192 } 193 if (high > low && high - low > (1 << 25) - 1) 194 params.branch_trampolines = 1; 195 } 196 197 if (params.branch_trampolines 198 || params.ppc476_workaround 199 || params.pic_fixup > 0) 200 ENABLE_RELAXATION; 201} 202 203/* Replaces default zero fill padding in executable sections with 204 "ba 0" instructions. This works around the ppc476 icache bug if we 205 have a function pointer tail call near the end of a page, some 206 small amount of padding, then the function called at the beginning 207 of the next page. If the "ba 0" is ever executed we should hit a 208 segv, so it's almost as good as an illegal instruction (zero). */ 209 210static void 211no_zero_padding (lang_statement_union_type *l) 212{ 213 if (l->header.type == lang_padding_statement_enum 214 && l->padding_statement.size != 0 215 && l->padding_statement.output_section != NULL 216 && (l->padding_statement.output_section->flags & SEC_CODE) != 0 217 && l->padding_statement.fill->size == 0) 218 { 219 struct _ppc_fill_type 220 { 221 size_t size; 222 unsigned char data[4]; 223 }; 224 static struct _ppc_fill_type fill_be = { 4, {0x48, 0, 0, 2} }; 225 static struct _ppc_fill_type fill_le = { 4, {2, 0, 0, 0x48} }; 226 227 if (bfd_big_endian (link_info.output_bfd)) 228 l->padding_statement.fill = (struct _fill_type *) &fill_be; 229 else 230 l->padding_statement.fill = (struct _fill_type *) &fill_le; 231 } 232} 233 234static void 235ppc_finish (void) 236{ 237 if (params.ppc476_workaround) 238 lang_for_each_statement (no_zero_padding); 239 if (!ppc_finish_symbols (&link_info)) 240 einfo (_("%X%P: ppc_finish_symbols problem %E\n")); 241 finish_default (); 242} 243 244EOF 245 246if grep -q 'ld_elf32_spu_emulation' ldemul-list.h; then 247 fragment <<EOF 248/* Special handling for embedded SPU executables. */ 249extern bfd_boolean embedded_spu_file (lang_input_statement_type *, const char *); 250 251static bfd_boolean 252ppc_recognized_file (lang_input_statement_type *entry) 253{ 254 if (embedded_spu_file (entry, "-m32")) 255 return TRUE; 256 257 return ldelf_load_symbols (entry); 258} 259 260EOF 261LDEMUL_RECOGNIZED_FILE=ppc_recognized_file 262fi 263 264# Define some shell vars to insert bits of code into the standard elf 265# parse_args and list_options functions. 266# 267PARSE_AND_LIST_PROLOGUE=${PARSE_AND_LIST_PROLOGUE}' 268enum ppc32_opt 269{ 270 OPTION_NO_TLS_OPT = 321, 271 OPTION_NO_TLS_GET_ADDR_OPT, 272 OPTION_NEW_PLT, 273 OPTION_OLD_PLT, 274 OPTION_PLT_ALIGN, 275 OPTION_NO_PLT_ALIGN, 276 OPTION_NO_INLINE_OPT, 277 OPTION_OLD_GOT, 278 OPTION_STUBSYMS, 279 OPTION_NO_STUBSYMS, 280 OPTION_PPC476_WORKAROUND, 281 OPTION_NO_PPC476_WORKAROUND, 282 OPTION_NO_PICFIXUP, 283 OPTION_VLE_RELOC_FIXUP 284}; 285' 286 287PARSE_AND_LIST_LONGOPTS=${PARSE_AND_LIST_LONGOPTS}' 288 { "emit-stub-syms", no_argument, NULL, OPTION_STUBSYMS }, 289 { "no-emit-stub-syms", no_argument, NULL, OPTION_NO_STUBSYMS }, 290 { "no-tls-optimize", no_argument, NULL, OPTION_NO_TLS_OPT }, 291 { "no-tls-get-addr-optimize", no_argument, NULL, OPTION_NO_TLS_GET_ADDR_OPT },' 292if test -z "$VXWORKS_BASE_EM_FILE" ; then 293 PARSE_AND_LIST_LONGOPTS=${PARSE_AND_LIST_LONGOPTS}' 294 { "secure-plt", no_argument, NULL, OPTION_NEW_PLT }, 295 { "bss-plt", no_argument, NULL, OPTION_OLD_PLT }, 296 { "plt-align", optional_argument, NULL, OPTION_PLT_ALIGN }, 297 { "no-plt-align", no_argument, NULL, OPTION_NO_PLT_ALIGN }, 298 { "no-inline-optimize", no_argument, NULL, OPTION_NO_INLINE_OPT }, 299 { "sdata-got", no_argument, NULL, OPTION_OLD_GOT },' 300fi 301PARSE_AND_LIST_LONGOPTS=${PARSE_AND_LIST_LONGOPTS}' 302 { "ppc476-workaround", optional_argument, NULL, OPTION_PPC476_WORKAROUND }, 303 { "no-ppc476-workaround", no_argument, NULL, OPTION_NO_PPC476_WORKAROUND }, 304 { "no-pic-fixup", no_argument, NULL, OPTION_NO_PICFIXUP }, 305 { "vle-reloc-fixup", no_argument, NULL, OPTION_VLE_RELOC_FIXUP }, 306' 307 308PARSE_AND_LIST_OPTIONS=${PARSE_AND_LIST_OPTIONS}' 309 fprintf (file, _("\ 310 --emit-stub-syms Label linker stubs with a symbol\n" 311 )); 312 fprintf (file, _("\ 313 --no-emit-stub-syms Don'\''t label linker stubs with a symbol\n" 314 )); 315 fprintf (file, _("\ 316 --no-tls-optimize Don'\''t try to optimize TLS accesses\n" 317 )); 318 fprintf (file, _("\ 319 --no-tls-get-addr-optimize Don'\''t use a special __tls_get_addr call\n" 320 ));' 321if test -z "$VXWORKS_BASE_EM_FILE" ; then 322 PARSE_AND_LIST_OPTIONS=${PARSE_AND_LIST_OPTIONS}'\ 323 fprintf (file, _("\ 324 --secure-plt Use new-style PLT if possible\n" 325 )); 326 fprintf (file, _("\ 327 --bss-plt Force old-style BSS PLT\n" 328 )); 329 fprintf (file, _("\ 330 --plt-align Align PLT call stubs to fit cache lines\n" 331 )); 332 fprintf (file, _("\ 333 --no-plt-align Dont'\''t align individual PLT call stubs\n" 334 )); 335 fprintf (file, _("\ 336 --no-inline-optimize Don'\''t convert inline PLT to direct calls\n" 337 )); 338 fprintf (file, _("\ 339 --sdata-got Force GOT location just before .sdata\n" 340 ));' 341fi 342PARSE_AND_LIST_OPTIONS=${PARSE_AND_LIST_OPTIONS}'\ 343 fprintf (file, _("\ 344 --ppc476-workaround [=pagesize]\n\ 345 Avoid a cache bug on ppc476\n" 346 )); 347 fprintf (file, _("\ 348 --no-ppc476-workaround Disable workaround\n" 349 )); 350 fprintf (file, _("\ 351 --no-pic-fixup Don'\''t edit non-pic to pic\n" 352 )); 353 fprintf (file, _("\ 354 --vle-reloc-fixup Correct old object file 16A/16D relocation\n" 355 )); 356' 357 358PARSE_AND_LIST_ARGS_CASES=${PARSE_AND_LIST_ARGS_CASES}' 359 case OPTION_STUBSYMS: 360 params.emit_stub_syms = 1; 361 break; 362 363 case OPTION_NO_STUBSYMS: 364 params.emit_stub_syms = 0; 365 break; 366 367 case OPTION_NO_TLS_OPT: 368 notlsopt = 1; 369 break; 370 371 case OPTION_NO_TLS_GET_ADDR_OPT: 372 params.no_tls_get_addr_opt = 1; 373 break; 374 375 case OPTION_NEW_PLT: 376 params.plt_style = PLT_NEW; 377 break; 378 379 case OPTION_OLD_PLT: 380 params.plt_style = PLT_OLD; 381 break; 382 383 case OPTION_PLT_ALIGN: 384 if (optarg != NULL) 385 { 386 char *end; 387 unsigned long val = strtoul (optarg, &end, 0); 388 if (*end || val > 5) 389 einfo (_("%F%P: invalid --plt-align `%s'\''\n"), optarg); 390 params.plt_stub_align = val; 391 } 392 else 393 params.plt_stub_align = 5; 394 break; 395 396 case OPTION_NO_PLT_ALIGN: 397 params.plt_stub_align = 0; 398 break; 399 400 case OPTION_NO_INLINE_OPT: 401 no_inline_opt = 1; 402 break; 403 404 case OPTION_OLD_GOT: 405 old_got = 1; 406 break; 407 408 case OPTION_TRADITIONAL_FORMAT: 409 notlsopt = 1; 410 params.no_tls_get_addr_opt = 1; 411 return FALSE; 412 413 case OPTION_PPC476_WORKAROUND: 414 params.ppc476_workaround = 1; 415 if (optarg != NULL) 416 { 417 char *end; 418 params.pagesize = strtoul (optarg, &end, 0); 419 if (*end 420 || (params.pagesize < 4096 && params.pagesize != 0) 421 || params.pagesize != (params.pagesize & -params.pagesize)) 422 einfo (_("%F%P: invalid pagesize `%s'\''\n"), optarg); 423 } 424 break; 425 426 case OPTION_NO_PPC476_WORKAROUND: 427 params.ppc476_workaround = 0; 428 break; 429 430 case OPTION_NO_PICFIXUP: 431 params.pic_fixup = -1; 432 break; 433 434 case OPTION_VLE_RELOC_FIXUP: 435 params.vle_reloc_fixup = 1; 436 break; 437' 438 439# Put these extra ppc32elf routines in ld_${EMULATION_NAME}_emulation 440# 441LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=ppc_after_open_output 442if test -z "$VXWORKS_BASE_EM_FILE" ; then 443 LDEMUL_AFTER_CHECK_RELOCS=ppc_after_check_relocs 444fi 445LDEMUL_BEFORE_ALLOCATION=ppc_before_allocation 446LDEMUL_FINISH=ppc_finish 447