1 /* Xstormy16-specific support for 32-bit ELF. 2 Copyright (C) 2000-2018 Free Software Foundation, Inc. 3 4 This file is part of BFD, the Binary File Descriptor library. 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 #include "sysdep.h" 22 #include "bfd.h" 23 #include "libbfd.h" 24 #include "elf-bfd.h" 25 #include "elf/xstormy16.h" 26 #include "libiberty.h" 27 28 /* Handle the R_XSTORMY16_24 reloc, which has an odd bit arrangement. */ 29 30 static bfd_reloc_status_type 31 xstormy16_elf_24_reloc (bfd *abfd, 32 arelent *reloc_entry, 33 asymbol *symbol, 34 void * data, 35 asection *input_section, 36 bfd *output_bfd, 37 char **error_message ATTRIBUTE_UNUSED) 38 { 39 bfd_vma relocation, x; 40 41 if (output_bfd != NULL) 42 { 43 reloc_entry->address += input_section->output_offset; 44 return bfd_reloc_ok; 45 } 46 47 if (reloc_entry->address > bfd_get_section_limit (abfd, input_section)) 48 return bfd_reloc_outofrange; 49 50 if (bfd_is_com_section (symbol->section)) 51 relocation = 0; 52 else 53 relocation = symbol->value; 54 55 relocation += symbol->section->output_section->vma; 56 relocation += symbol->section->output_offset; 57 relocation += reloc_entry->addend; 58 59 x = bfd_get_32 (abfd, (bfd_byte *) data + reloc_entry->address); 60 x &= 0x0000ff00; 61 x |= relocation & 0xff; 62 x |= (relocation << 8) & 0xffff0000; 63 bfd_put_32 (abfd, x, (bfd_byte *) data + reloc_entry->address); 64 65 if (relocation & ~ (bfd_vma) 0xffffff) 66 return bfd_reloc_overflow; 67 68 return bfd_reloc_ok; 69 } 70 71 static reloc_howto_type xstormy16_elf_howto_table [] = 72 { 73 /* This reloc does nothing. */ 74 HOWTO (R_XSTORMY16_NONE, /* type */ 75 0, /* rightshift */ 76 3, /* size (0 = byte, 1 = short, 2 = long) */ 77 0, /* bitsize */ 78 FALSE, /* pc_relative */ 79 0, /* bitpos */ 80 complain_overflow_dont, /* complain_on_overflow */ 81 bfd_elf_generic_reloc, /* special_function */ 82 "R_XSTORMY16_NONE", /* name */ 83 FALSE, /* partial_inplace */ 84 0, /* src_mask */ 85 0, /* dst_mask */ 86 FALSE), /* pcrel_offset */ 87 88 /* A 32 bit absolute relocation. */ 89 HOWTO (R_XSTORMY16_32, /* type */ 90 0, /* rightshift */ 91 2, /* size (0 = byte, 1 = short, 2 = long) */ 92 32, /* bitsize */ 93 FALSE, /* pc_relative */ 94 0, /* bitpos */ 95 complain_overflow_dont, /* complain_on_overflow */ 96 bfd_elf_generic_reloc, /* special_function */ 97 "R_XSTORMY16_32", /* name */ 98 FALSE, /* partial_inplace */ 99 0, /* src_mask */ 100 0xffffffff, /* dst_mask */ 101 FALSE), /* pcrel_offset */ 102 103 /* A 16 bit absolute relocation. */ 104 HOWTO (R_XSTORMY16_16, /* type */ 105 0, /* rightshift */ 106 1, /* size (0 = byte, 1 = short, 2 = long) */ 107 16, /* bitsize */ 108 FALSE, /* pc_relative */ 109 0, /* bitpos */ 110 complain_overflow_bitfield, /* complain_on_overflow */ 111 bfd_elf_generic_reloc, /* special_function */ 112 "R_XSTORMY16_16", /* name */ 113 FALSE, /* partial_inplace */ 114 0, /* src_mask */ 115 0xffff, /* dst_mask */ 116 FALSE), /* pcrel_offset */ 117 118 /* An 8 bit absolute relocation. */ 119 HOWTO (R_XSTORMY16_8, /* type */ 120 0, /* rightshift */ 121 0, /* size (0 = byte, 1 = short, 2 = long) */ 122 8, /* bitsize */ 123 FALSE, /* pc_relative */ 124 0, /* bitpos */ 125 complain_overflow_unsigned, /* complain_on_overflow */ 126 bfd_elf_generic_reloc, /* special_function */ 127 "R_XSTORMY16_8", /* name */ 128 FALSE, /* partial_inplace */ 129 0, /* src_mask */ 130 0xff, /* dst_mask */ 131 FALSE), /* pcrel_offset */ 132 133 /* A 32 bit pc-relative relocation. */ 134 HOWTO (R_XSTORMY16_PC32, /* type */ 135 0, /* rightshift */ 136 2, /* size (0 = byte, 1 = short, 2 = long) */ 137 32, /* bitsize */ 138 TRUE, /* pc_relative */ 139 0, /* bitpos */ 140 complain_overflow_dont, /* complain_on_overflow */ 141 bfd_elf_generic_reloc, /* special_function */ 142 "R_XSTORMY16_PC32", /* name */ 143 FALSE, /* partial_inplace */ 144 0, /* src_mask */ 145 0xffffffff, /* dst_mask */ 146 TRUE), /* pcrel_offset */ 147 148 /* A 16 bit pc-relative relocation. */ 149 HOWTO (R_XSTORMY16_PC16, /* type */ 150 0, /* rightshift */ 151 1, /* size (0 = byte, 1 = short, 2 = long) */ 152 16, /* bitsize */ 153 TRUE, /* pc_relative */ 154 0, /* bitpos */ 155 complain_overflow_signed, /* complain_on_overflow */ 156 bfd_elf_generic_reloc, /* special_function */ 157 "R_XSTORMY16_PC16", /* name */ 158 FALSE, /* partial_inplace */ 159 0, /* src_mask */ 160 0xffffffff, /* dst_mask */ 161 TRUE), /* pcrel_offset */ 162 163 /* An 8 bit pc-relative relocation. */ 164 HOWTO (R_XSTORMY16_PC8, /* type */ 165 0, /* rightshift */ 166 0, /* size (0 = byte, 1 = short, 2 = long) */ 167 8, /* bitsize */ 168 TRUE, /* pc_relative */ 169 0, /* bitpos */ 170 complain_overflow_signed, /* complain_on_overflow */ 171 bfd_elf_generic_reloc, /* special_function */ 172 "R_XSTORMY16_PC8", /* name */ 173 FALSE, /* partial_inplace */ 174 0, /* src_mask */ 175 0xffffffff, /* dst_mask */ 176 TRUE), /* pcrel_offset */ 177 178 /* A 12-bit pc-relative relocation suitable for the branch instructions. */ 179 HOWTO (R_XSTORMY16_REL_12, /* type */ 180 1, /* rightshift */ 181 1, /* size (0 = byte, 1 = short, 2 = long) */ 182 11, /* bitsize */ 183 TRUE, /* pc_relative */ 184 1, /* bitpos */ 185 complain_overflow_signed, /* complain_on_overflow */ 186 bfd_elf_generic_reloc, /* special_function */ 187 "R_XSTORMY16_REL_12", /* name */ 188 FALSE, /* partial_inplace */ 189 0, /* src_mask */ 190 0x0ffe, /* dst_mask */ 191 TRUE), /* pcrel_offset */ 192 193 /* A 24-bit absolute relocation suitable for the jump instructions. */ 194 HOWTO (R_XSTORMY16_24, /* type */ 195 0, /* rightshift */ 196 2, /* size (0 = byte, 1 = short, 2 = long) */ 197 24, /* bitsize */ 198 FALSE, /* pc_relative */ 199 0, /* bitpos */ 200 complain_overflow_unsigned, /* complain_on_overflow */ 201 xstormy16_elf_24_reloc, /* special_function */ 202 "R_XSTORMY16_24", /* name */ 203 TRUE, /* partial_inplace */ 204 0, /* src_mask */ 205 0xffff00ff, /* dst_mask */ 206 TRUE), /* pcrel_offset */ 207 208 /* A 16 bit absolute relocation to a function pointer. */ 209 HOWTO (R_XSTORMY16_FPTR16, /* type */ 210 0, /* rightshift */ 211 1, /* size (0 = byte, 1 = short, 2 = long) */ 212 16, /* bitsize */ 213 FALSE, /* pc_relative */ 214 0, /* bitpos */ 215 complain_overflow_bitfield, /* complain_on_overflow */ 216 bfd_elf_generic_reloc, /* special_function */ 217 "R_XSTORMY16_FPTR16", /* name */ 218 FALSE, /* partial_inplace */ 219 0, /* src_mask */ 220 0xffffffff, /* dst_mask */ 221 FALSE), /* pcrel_offset */ 222 223 /* Low order 16 bit value of a high memory address. */ 224 HOWTO (R_XSTORMY16_LO16, /* type */ 225 0, /* rightshift */ 226 1, /* size (0 = byte, 1 = short, 2 = long) */ 227 16, /* bitsize */ 228 FALSE, /* pc_relative */ 229 0, /* bitpos */ 230 complain_overflow_dont, /* complain_on_overflow */ 231 bfd_elf_generic_reloc, /* special_function */ 232 "R_XSTORMY16_LO16", /* name */ 233 FALSE, /* partial_inplace */ 234 0, /* src_mask */ 235 0xffff, /* dst_mask */ 236 FALSE), /* pcrel_offset */ 237 238 /* High order 16 bit value of a high memory address. */ 239 HOWTO (R_XSTORMY16_HI16, /* type */ 240 16, /* rightshift */ 241 1, /* size (0 = byte, 1 = short, 2 = long) */ 242 16, /* bitsize */ 243 FALSE, /* pc_relative */ 244 0, /* bitpos */ 245 complain_overflow_dont, /* complain_on_overflow */ 246 bfd_elf_generic_reloc, /* special_function */ 247 "R_XSTORMY16_HI16", /* name */ 248 FALSE, /* partial_inplace */ 249 0, /* src_mask */ 250 0xffff, /* dst_mask */ 251 FALSE), /* pcrel_offset */ 252 253 /* A 12 bit absolute relocation. */ 254 HOWTO (R_XSTORMY16_12, /* type */ 255 0, /* rightshift */ 256 1, /* size (0 = byte, 1 = short, 2 = long) */ 257 12, /* bitsize */ 258 FALSE, /* pc_relative */ 259 0, /* bitpos */ 260 complain_overflow_signed, /* complain_on_overflow */ 261 bfd_elf_generic_reloc, /* special_function */ 262 "R_XSTORMY16_12", /* name */ 263 FALSE, /* partial_inplace */ 264 0x0000, /* src_mask */ 265 0x0fff, /* dst_mask */ 266 FALSE), /* pcrel_offset */ 267 }; 268 269 static reloc_howto_type xstormy16_elf_howto_table2 [] = 270 { 271 /* GNU extension to record C++ vtable hierarchy */ 272 HOWTO (R_XSTORMY16_GNU_VTINHERIT, /* type */ 273 0, /* rightshift */ 274 2, /* size (0 = byte, 1 = short, 2 = long) */ 275 0, /* bitsize */ 276 FALSE, /* pc_relative */ 277 0, /* bitpos */ 278 complain_overflow_dont, /* complain_on_overflow */ 279 NULL, /* special_function */ 280 "R_XSTORMY16_GNU_VTINHERIT", /* name */ 281 FALSE, /* partial_inplace */ 282 0, /* src_mask */ 283 0, /* dst_mask */ 284 FALSE), /* pcrel_offset */ 285 286 /* GNU extension to record C++ vtable member usage */ 287 HOWTO (R_XSTORMY16_GNU_VTENTRY, /* type */ 288 0, /* rightshift */ 289 2, /* size (0 = byte, 1 = short, 2 = long) */ 290 0, /* bitsize */ 291 FALSE, /* pc_relative */ 292 0, /* bitpos */ 293 complain_overflow_dont, /* complain_on_overflow */ 294 _bfd_elf_rel_vtable_reloc_fn, /* special_function */ 295 "R_XSTORMY16_GNU_VTENTRY", /* name */ 296 FALSE, /* partial_inplace */ 297 0, /* src_mask */ 298 0, /* dst_mask */ 299 FALSE), /* pcrel_offset */ 300 301 }; 302 303 /* Map BFD reloc types to XSTORMY16 ELF reloc types. */ 304 305 typedef struct xstormy16_reloc_map 306 { 307 bfd_reloc_code_real_type bfd_reloc_val; 308 unsigned int xstormy16_reloc_val; 309 reloc_howto_type * table; 310 } reloc_map; 311 312 static const reloc_map xstormy16_reloc_map [] = 313 { 314 { BFD_RELOC_NONE, R_XSTORMY16_NONE, xstormy16_elf_howto_table }, 315 { BFD_RELOC_32, R_XSTORMY16_32, xstormy16_elf_howto_table }, 316 { BFD_RELOC_16, R_XSTORMY16_16, xstormy16_elf_howto_table }, 317 { BFD_RELOC_8, R_XSTORMY16_8, xstormy16_elf_howto_table }, 318 { BFD_RELOC_32_PCREL, R_XSTORMY16_PC32, xstormy16_elf_howto_table }, 319 { BFD_RELOC_16_PCREL, R_XSTORMY16_PC16, xstormy16_elf_howto_table }, 320 { BFD_RELOC_8_PCREL, R_XSTORMY16_PC8, xstormy16_elf_howto_table }, 321 { BFD_RELOC_XSTORMY16_REL_12, R_XSTORMY16_REL_12, xstormy16_elf_howto_table }, 322 { BFD_RELOC_XSTORMY16_24, R_XSTORMY16_24, xstormy16_elf_howto_table }, 323 { BFD_RELOC_XSTORMY16_FPTR16, R_XSTORMY16_FPTR16, xstormy16_elf_howto_table }, 324 { BFD_RELOC_LO16, R_XSTORMY16_LO16, xstormy16_elf_howto_table }, 325 { BFD_RELOC_HI16, R_XSTORMY16_HI16, xstormy16_elf_howto_table }, 326 { BFD_RELOC_XSTORMY16_12, R_XSTORMY16_12, xstormy16_elf_howto_table }, 327 { BFD_RELOC_VTABLE_INHERIT, R_XSTORMY16_GNU_VTINHERIT, xstormy16_elf_howto_table2 }, 328 { BFD_RELOC_VTABLE_ENTRY, R_XSTORMY16_GNU_VTENTRY, xstormy16_elf_howto_table2 }, 329 }; 330 331 static reloc_howto_type * 332 xstormy16_reloc_type_lookup (bfd * abfd ATTRIBUTE_UNUSED, 333 bfd_reloc_code_real_type code) 334 { 335 unsigned int i; 336 337 for (i = ARRAY_SIZE (xstormy16_reloc_map); i--;) 338 { 339 const reloc_map * entry; 340 341 entry = xstormy16_reloc_map + i; 342 343 if (entry->bfd_reloc_val == code) 344 return entry->table + (entry->xstormy16_reloc_val 345 - entry->table[0].type); 346 } 347 348 return NULL; 349 } 350 351 static reloc_howto_type * 352 xstormy16_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED, 353 const char *r_name) 354 { 355 unsigned int i; 356 357 for (i = 0; 358 i < (sizeof (xstormy16_elf_howto_table) 359 / sizeof (xstormy16_elf_howto_table[0])); 360 i++) 361 if (xstormy16_elf_howto_table[i].name != NULL 362 && strcasecmp (xstormy16_elf_howto_table[i].name, r_name) == 0) 363 return &xstormy16_elf_howto_table[i]; 364 365 for (i = 0; 366 i < (sizeof (xstormy16_elf_howto_table2) 367 / sizeof (xstormy16_elf_howto_table2[0])); 368 i++) 369 if (xstormy16_elf_howto_table2[i].name != NULL 370 && strcasecmp (xstormy16_elf_howto_table2[i].name, r_name) == 0) 371 return &xstormy16_elf_howto_table2[i]; 372 373 return NULL; 374 } 375 376 /* Set the howto pointer for an XSTORMY16 ELF reloc. */ 377 378 static bfd_boolean 379 xstormy16_info_to_howto_rela (bfd * abfd, 380 arelent * cache_ptr, 381 Elf_Internal_Rela * dst) 382 { 383 unsigned int r_type = ELF32_R_TYPE (dst->r_info); 384 385 if (r_type <= (unsigned int) R_XSTORMY16_12) 386 cache_ptr->howto = &xstormy16_elf_howto_table [r_type]; 387 else if (r_type - R_XSTORMY16_GNU_VTINHERIT 388 <= ((unsigned int) R_XSTORMY16_GNU_VTENTRY 389 - (unsigned int) R_XSTORMY16_GNU_VTINHERIT)) 390 cache_ptr->howto 391 = &xstormy16_elf_howto_table2 [r_type - R_XSTORMY16_GNU_VTINHERIT]; 392 else 393 { 394 /* xgettext:c-format */ 395 _bfd_error_handler (_("%pB: unsupported relocation type %#x"), 396 abfd, r_type); 397 bfd_set_error (bfd_error_bad_value); 398 return FALSE; 399 } 400 return TRUE; 401 } 402 403 /* We support 16-bit pointers to code above 64k by generating a thunk 404 below 64k containing a JMPF instruction to the final address. We 405 cannot, unfortunately, minimize the number of thunks unless the 406 -relax switch is given, as otherwise we have no idea where the 407 sections will fall in the address space. */ 408 409 static bfd_boolean 410 xstormy16_elf_check_relocs (bfd *abfd, 411 struct bfd_link_info *info, 412 asection *sec, 413 const Elf_Internal_Rela *relocs) 414 { 415 const Elf_Internal_Rela *rel, *relend; 416 struct elf_link_hash_entry **sym_hashes; 417 Elf_Internal_Shdr *symtab_hdr; 418 bfd_vma *local_plt_offsets; 419 asection *splt; 420 bfd *dynobj; 421 422 if (bfd_link_relocatable (info)) 423 return TRUE; 424 425 symtab_hdr = &elf_tdata(abfd)->symtab_hdr; 426 sym_hashes = elf_sym_hashes (abfd); 427 local_plt_offsets = elf_local_got_offsets (abfd); 428 dynobj = elf_hash_table(info)->dynobj; 429 430 relend = relocs + sec->reloc_count; 431 for (rel = relocs; rel < relend; ++rel) 432 { 433 unsigned long r_symndx; 434 struct elf_link_hash_entry *h; 435 bfd_vma *offset; 436 437 r_symndx = ELF32_R_SYM (rel->r_info); 438 if (r_symndx < symtab_hdr->sh_info) 439 h = NULL; 440 else 441 { 442 h = sym_hashes[r_symndx - symtab_hdr->sh_info]; 443 while (h->root.type == bfd_link_hash_indirect 444 || h->root.type == bfd_link_hash_warning) 445 h = (struct elf_link_hash_entry *) h->root.u.i.link; 446 } 447 448 switch (ELF32_R_TYPE (rel->r_info)) 449 { 450 /* This relocation describes a 16-bit pointer to a function. 451 We may need to allocate a thunk in low memory; reserve memory 452 for it now. */ 453 case R_XSTORMY16_FPTR16: 454 if (rel->r_addend != 0) 455 { 456 (*info->callbacks->warning) 457 (info, _("non-zero addend in @fptr reloc"), 0, 458 abfd, 0, 0); 459 } 460 461 if (dynobj == NULL) 462 elf_hash_table (info)->dynobj = dynobj = abfd; 463 splt = elf_hash_table (info)->splt; 464 if (splt == NULL) 465 { 466 flagword flags = (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS 467 | SEC_IN_MEMORY | SEC_LINKER_CREATED 468 | SEC_READONLY | SEC_CODE); 469 470 splt = bfd_make_section_anyway_with_flags (dynobj, ".plt", 471 flags); 472 elf_hash_table (info)->splt = splt; 473 if (splt == NULL 474 || ! bfd_set_section_alignment (dynobj, splt, 1)) 475 return FALSE; 476 } 477 478 if (h != NULL) 479 offset = &h->plt.offset; 480 else 481 { 482 if (local_plt_offsets == NULL) 483 { 484 size_t size; 485 unsigned int i; 486 487 size = symtab_hdr->sh_info * sizeof (bfd_vma); 488 local_plt_offsets = bfd_alloc (abfd, size); 489 if (local_plt_offsets == NULL) 490 return FALSE; 491 elf_local_got_offsets (abfd) = local_plt_offsets; 492 493 for (i = 0; i < symtab_hdr->sh_info; i++) 494 local_plt_offsets[i] = (bfd_vma) -1; 495 } 496 offset = &local_plt_offsets[r_symndx]; 497 } 498 499 if (*offset == (bfd_vma) -1) 500 { 501 *offset = splt->size; 502 splt->size += 4; 503 } 504 break; 505 506 /* This relocation describes the C++ object vtable hierarchy. 507 Reconstruct it for later use during GC. */ 508 case R_XSTORMY16_GNU_VTINHERIT: 509 if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset)) 510 return FALSE; 511 break; 512 513 /* This relocation describes which C++ vtable entries are actually 514 used. Record for later use during GC. */ 515 case R_XSTORMY16_GNU_VTENTRY: 516 BFD_ASSERT (h != NULL); 517 if (h != NULL 518 && !bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_addend)) 519 return FALSE; 520 break; 521 } 522 } 523 524 return TRUE; 525 } 526 527 /* A subroutine of xstormy16_elf_relax_section. If the global symbol H 528 is within the low 64k, remove any entry for it in the plt. */ 529 530 struct relax_plt_data 531 { 532 asection *splt; 533 bfd_boolean *again; 534 }; 535 536 static bfd_boolean 537 xstormy16_relax_plt_check (struct elf_link_hash_entry *h, void * xdata) 538 { 539 struct relax_plt_data *data = (struct relax_plt_data *) xdata; 540 541 if (h->plt.offset != (bfd_vma) -1) 542 { 543 bfd_vma address; 544 545 if (h->root.type == bfd_link_hash_undefined 546 || h->root.type == bfd_link_hash_undefweak) 547 address = 0; 548 else 549 address = (h->root.u.def.section->output_section->vma 550 + h->root.u.def.section->output_offset 551 + h->root.u.def.value); 552 553 if (address <= 0xffff) 554 { 555 h->plt.offset = -1; 556 data->splt->size -= 4; 557 *data->again = TRUE; 558 } 559 } 560 561 return TRUE; 562 } 563 564 /* A subroutine of xstormy16_elf_relax_section. If the global symbol H 565 previously had a plt entry, give it a new entry offset. */ 566 567 static bfd_boolean 568 xstormy16_relax_plt_realloc (struct elf_link_hash_entry *h, void * xdata) 569 { 570 bfd_vma *entry = (bfd_vma *) xdata; 571 572 if (h->plt.offset != (bfd_vma) -1) 573 { 574 h->plt.offset = *entry; 575 *entry += 4; 576 } 577 578 return TRUE; 579 } 580 581 static bfd_boolean 582 xstormy16_elf_relax_section (bfd *dynobj, 583 asection *splt, 584 struct bfd_link_info *info, 585 bfd_boolean *again) 586 { 587 struct relax_plt_data relax_plt_data; 588 bfd *ibfd; 589 590 /* Assume nothing changes. */ 591 *again = FALSE; 592 593 if (bfd_link_relocatable (info)) 594 return TRUE; 595 596 /* We only relax the .plt section at the moment. */ 597 if (dynobj != elf_hash_table (info)->dynobj 598 || strcmp (splt->name, ".plt") != 0) 599 return TRUE; 600 601 /* Quick check for an empty plt. */ 602 if (splt->size == 0) 603 return TRUE; 604 605 /* Map across all global symbols; see which ones happen to 606 fall in the low 64k. */ 607 relax_plt_data.splt = splt; 608 relax_plt_data.again = again; 609 elf_link_hash_traverse (elf_hash_table (info), xstormy16_relax_plt_check, 610 &relax_plt_data); 611 612 /* Likewise for local symbols, though that's somewhat less convenient 613 as we have to walk the list of input bfds and swap in symbol data. */ 614 for (ibfd = info->input_bfds; ibfd ; ibfd = ibfd->link.next) 615 { 616 bfd_vma *local_plt_offsets = elf_local_got_offsets (ibfd); 617 Elf_Internal_Shdr *symtab_hdr; 618 Elf_Internal_Sym *isymbuf = NULL; 619 unsigned int idx; 620 621 if (! local_plt_offsets) 622 continue; 623 624 symtab_hdr = &elf_tdata (ibfd)->symtab_hdr; 625 if (symtab_hdr->sh_info != 0) 626 { 627 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents; 628 if (isymbuf == NULL) 629 isymbuf = bfd_elf_get_elf_syms (ibfd, symtab_hdr, 630 symtab_hdr->sh_info, 0, 631 NULL, NULL, NULL); 632 if (isymbuf == NULL) 633 return FALSE; 634 } 635 636 for (idx = 0; idx < symtab_hdr->sh_info; ++idx) 637 { 638 Elf_Internal_Sym *isym; 639 asection *tsec; 640 bfd_vma address; 641 642 if (local_plt_offsets[idx] == (bfd_vma) -1) 643 continue; 644 645 isym = &isymbuf[idx]; 646 if (isym->st_shndx == SHN_UNDEF) 647 continue; 648 else if (isym->st_shndx == SHN_ABS) 649 tsec = bfd_abs_section_ptr; 650 else if (isym->st_shndx == SHN_COMMON) 651 tsec = bfd_com_section_ptr; 652 else 653 tsec = bfd_section_from_elf_index (ibfd, isym->st_shndx); 654 655 address = (tsec->output_section->vma 656 + tsec->output_offset 657 + isym->st_value); 658 if (address <= 0xffff) 659 { 660 local_plt_offsets[idx] = -1; 661 splt->size -= 4; 662 *again = TRUE; 663 } 664 } 665 666 if (isymbuf != NULL 667 && symtab_hdr->contents != (unsigned char *) isymbuf) 668 { 669 if (! info->keep_memory) 670 free (isymbuf); 671 else 672 { 673 /* Cache the symbols for elf_link_input_bfd. */ 674 symtab_hdr->contents = (unsigned char *) isymbuf; 675 } 676 } 677 } 678 679 /* If we changed anything, walk the symbols again to reallocate 680 .plt entry addresses. */ 681 if (*again && splt->size > 0) 682 { 683 bfd_vma entry = 0; 684 685 elf_link_hash_traverse (elf_hash_table (info), 686 xstormy16_relax_plt_realloc, &entry); 687 688 for (ibfd = info->input_bfds; ibfd ; ibfd = ibfd->link.next) 689 { 690 bfd_vma *local_plt_offsets = elf_local_got_offsets (ibfd); 691 unsigned int nlocals = elf_tdata (ibfd)->symtab_hdr.sh_info; 692 unsigned int idx; 693 694 if (! local_plt_offsets) 695 continue; 696 697 for (idx = 0; idx < nlocals; ++idx) 698 if (local_plt_offsets[idx] != (bfd_vma) -1) 699 { 700 local_plt_offsets[idx] = entry; 701 entry += 4; 702 } 703 } 704 } 705 706 return TRUE; 707 } 708 709 static bfd_boolean 710 xstormy16_elf_always_size_sections (bfd *output_bfd ATTRIBUTE_UNUSED, 711 struct bfd_link_info *info) 712 { 713 bfd *dynobj; 714 asection *splt; 715 716 if (bfd_link_relocatable (info)) 717 return TRUE; 718 719 dynobj = elf_hash_table (info)->dynobj; 720 if (dynobj == NULL) 721 return TRUE; 722 723 splt = elf_hash_table (info)->splt; 724 BFD_ASSERT (splt != NULL); 725 726 splt->contents = bfd_zalloc (dynobj, splt->size); 727 if (splt->contents == NULL) 728 return FALSE; 729 730 return TRUE; 731 } 732 733 /* Relocate an XSTORMY16 ELF section. 734 735 The RELOCATE_SECTION function is called by the new ELF backend linker 736 to handle the relocations for a section. 737 738 The relocs are always passed as Rela structures; if the section 739 actually uses Rel structures, the r_addend field will always be 740 zero. 741 742 This function is responsible for adjusting the section contents as 743 necessary, and (if using Rela relocs and generating a relocatable 744 output file) adjusting the reloc addend as necessary. 745 746 This function does not have to worry about setting the reloc 747 address or the reloc symbol index. 748 749 LOCAL_SYMS is a pointer to the swapped in local symbols. 750 751 LOCAL_SECTIONS is an array giving the section in the input file 752 corresponding to the st_shndx field of each local symbol. 753 754 The global hash table entry for the global symbols can be found 755 via elf_sym_hashes (input_bfd). 756 757 When generating relocatable output, this function must handle 758 STB_LOCAL/STT_SECTION symbols specially. The output symbol is 759 going to be the section symbol corresponding to the output 760 section, which means that the addend must be adjusted 761 accordingly. */ 762 763 static bfd_boolean 764 xstormy16_elf_relocate_section (bfd * output_bfd ATTRIBUTE_UNUSED, 765 struct bfd_link_info * info, 766 bfd * input_bfd, 767 asection * input_section, 768 bfd_byte * contents, 769 Elf_Internal_Rela * relocs, 770 Elf_Internal_Sym * local_syms, 771 asection ** local_sections) 772 { 773 Elf_Internal_Shdr * symtab_hdr; 774 struct elf_link_hash_entry ** sym_hashes; 775 Elf_Internal_Rela * rel; 776 Elf_Internal_Rela * relend; 777 asection *splt; 778 779 symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr; 780 sym_hashes = elf_sym_hashes (input_bfd); 781 relend = relocs + input_section->reloc_count; 782 783 splt = elf_hash_table (info)->splt; 784 785 for (rel = relocs; rel < relend; rel ++) 786 { 787 reloc_howto_type * howto; 788 unsigned long r_symndx; 789 Elf_Internal_Sym * sym; 790 asection * sec; 791 struct elf_link_hash_entry * h; 792 bfd_vma relocation; 793 bfd_reloc_status_type r; 794 const char * name = NULL; 795 int r_type; 796 797 r_type = ELF32_R_TYPE (rel->r_info); 798 799 if ( r_type == R_XSTORMY16_GNU_VTINHERIT 800 || r_type == R_XSTORMY16_GNU_VTENTRY) 801 continue; 802 803 r_symndx = ELF32_R_SYM (rel->r_info); 804 howto = xstormy16_elf_howto_table + ELF32_R_TYPE (rel->r_info); 805 h = NULL; 806 sym = NULL; 807 sec = NULL; 808 809 if (r_symndx < symtab_hdr->sh_info) 810 { 811 sym = local_syms + r_symndx; 812 sec = local_sections [r_symndx]; 813 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, &sec, rel); 814 } 815 else 816 { 817 bfd_boolean unresolved_reloc, warned, ignored; 818 819 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel, 820 r_symndx, symtab_hdr, sym_hashes, 821 h, sec, relocation, 822 unresolved_reloc, warned, ignored); 823 } 824 825 if (sec != NULL && discarded_section (sec)) 826 RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section, 827 rel, 1, relend, howto, 0, contents); 828 829 if (bfd_link_relocatable (info)) 830 continue; 831 832 if (h != NULL) 833 name = h->root.root.string; 834 else 835 { 836 name = (bfd_elf_string_from_elf_section 837 (input_bfd, symtab_hdr->sh_link, sym->st_name)); 838 if (name == NULL || *name == '\0') 839 name = bfd_section_name (input_bfd, sec); 840 } 841 842 switch (ELF32_R_TYPE (rel->r_info)) 843 { 844 case R_XSTORMY16_24: 845 { 846 bfd_vma reloc = relocation + rel->r_addend; 847 unsigned int x; 848 849 x = bfd_get_32 (input_bfd, contents + rel->r_offset); 850 x &= 0x0000ff00; 851 x |= reloc & 0xff; 852 x |= (reloc << 8) & 0xffff0000; 853 bfd_put_32 (input_bfd, x, contents + rel->r_offset); 854 855 if (reloc & ~0xffffff) 856 r = bfd_reloc_overflow; 857 else 858 r = bfd_reloc_ok; 859 break; 860 } 861 862 case R_XSTORMY16_FPTR16: 863 { 864 bfd_vma *plt_offset; 865 866 if (h != NULL) 867 plt_offset = &h->plt.offset; 868 else 869 plt_offset = elf_local_got_offsets (input_bfd) + r_symndx; 870 871 if (relocation <= 0xffff) 872 { 873 /* If the symbol is in range for a 16-bit address, we should 874 have deallocated the plt entry in relax_section. */ 875 BFD_ASSERT (*plt_offset == (bfd_vma) -1); 876 } 877 else 878 { 879 /* If the symbol is out of range for a 16-bit address, 880 we must have allocated a plt entry. */ 881 BFD_ASSERT (*plt_offset != (bfd_vma) -1); 882 883 /* If this is the first time we've processed this symbol, 884 fill in the plt entry with the correct symbol address. */ 885 if ((*plt_offset & 1) == 0) 886 { 887 unsigned int x; 888 889 x = 0x00000200; /* jmpf */ 890 x |= relocation & 0xff; 891 x |= (relocation << 8) & 0xffff0000; 892 bfd_put_32 (input_bfd, x, splt->contents + *plt_offset); 893 *plt_offset |= 1; 894 } 895 896 relocation = (splt->output_section->vma 897 + splt->output_offset 898 + (*plt_offset & -2)); 899 } 900 r = _bfd_final_link_relocate (howto, input_bfd, input_section, 901 contents, rel->r_offset, 902 relocation, 0); 903 break; 904 } 905 906 default: 907 r = _bfd_final_link_relocate (howto, input_bfd, input_section, 908 contents, rel->r_offset, 909 relocation, rel->r_addend); 910 break; 911 } 912 913 if (r != bfd_reloc_ok) 914 { 915 const char * msg = NULL; 916 917 switch (r) 918 { 919 case bfd_reloc_overflow: 920 (*info->callbacks->reloc_overflow) 921 (info, (h ? &h->root : NULL), name, howto->name, 922 (bfd_vma) 0, input_bfd, input_section, rel->r_offset); 923 break; 924 925 case bfd_reloc_undefined: 926 (*info->callbacks->undefined_symbol) 927 (info, name, input_bfd, input_section, rel->r_offset, TRUE); 928 break; 929 930 case bfd_reloc_outofrange: 931 msg = _("internal error: out of range error"); 932 break; 933 934 case bfd_reloc_notsupported: 935 msg = _("internal error: unsupported relocation error"); 936 break; 937 938 case bfd_reloc_dangerous: 939 msg = _("internal error: dangerous relocation"); 940 break; 941 942 default: 943 msg = _("internal error: unknown error"); 944 break; 945 } 946 947 if (msg) 948 (*info->callbacks->warning) (info, msg, name, input_bfd, 949 input_section, rel->r_offset); 950 } 951 } 952 953 return TRUE; 954 } 955 956 /* This must exist if dynobj is ever set. */ 957 958 static bfd_boolean 959 xstormy16_elf_finish_dynamic_sections (bfd *abfd ATTRIBUTE_UNUSED, 960 struct bfd_link_info *info) 961 { 962 bfd *dynobj = elf_hash_table (info)->dynobj; 963 asection *splt = elf_hash_table (info)->splt; 964 965 /* As an extra sanity check, verify that all plt entries have 966 been filled in. */ 967 968 if (dynobj != NULL && splt != NULL) 969 { 970 bfd_byte *contents = splt->contents; 971 unsigned int i, size = splt->size; 972 973 for (i = 0; i < size; i += 4) 974 { 975 unsigned int x = bfd_get_32 (dynobj, contents + i); 976 977 BFD_ASSERT (x != 0); 978 } 979 } 980 981 return TRUE; 982 } 983 984 /* Return the section that should be marked against GC for a given 985 relocation. */ 986 987 static asection * 988 xstormy16_elf_gc_mark_hook (asection *sec, 989 struct bfd_link_info *info, 990 Elf_Internal_Rela *rel, 991 struct elf_link_hash_entry *h, 992 Elf_Internal_Sym *sym) 993 { 994 if (h != NULL) 995 switch (ELF32_R_TYPE (rel->r_info)) 996 { 997 case R_XSTORMY16_GNU_VTINHERIT: 998 case R_XSTORMY16_GNU_VTENTRY: 999 return NULL; 1000 } 1001 1002 return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym); 1003 } 1004 1005 #define ELF_ARCH bfd_arch_xstormy16 1006 #define ELF_MACHINE_CODE EM_XSTORMY16 1007 #define ELF_MAXPAGESIZE 0x100 1008 1009 #define TARGET_LITTLE_SYM xstormy16_elf32_vec 1010 #define TARGET_LITTLE_NAME "elf32-xstormy16" 1011 1012 #define elf_info_to_howto_rel NULL 1013 #define elf_info_to_howto xstormy16_info_to_howto_rela 1014 #define elf_backend_relocate_section xstormy16_elf_relocate_section 1015 #define elf_backend_gc_mark_hook xstormy16_elf_gc_mark_hook 1016 #define elf_backend_check_relocs xstormy16_elf_check_relocs 1017 #define elf_backend_always_size_sections \ 1018 xstormy16_elf_always_size_sections 1019 #define elf_backend_omit_section_dynsym \ 1020 _bfd_elf_omit_section_dynsym_all 1021 #define elf_backend_finish_dynamic_sections \ 1022 xstormy16_elf_finish_dynamic_sections 1023 1024 #define elf_backend_can_gc_sections 1 1025 #define elf_backend_rela_normal 1 1026 1027 #define bfd_elf32_bfd_reloc_type_lookup xstormy16_reloc_type_lookup 1028 #define bfd_elf32_bfd_reloc_name_lookup \ 1029 xstormy16_reloc_name_lookup 1030 #define bfd_elf32_bfd_relax_section xstormy16_elf_relax_section 1031 1032 #include "elf32-target.h" 1033