1 /* D10V-specific support for 32-bit ELF 2 Copyright 1996, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 3 2007 Free Software Foundation, Inc. 4 Contributed by Martin Hunt (hunt@cygnus.com). 5 6 This file is part of BFD, the Binary File Descriptor library. 7 8 This program is free software; you can redistribute it and/or modify 9 it under the terms of the GNU General Public License as published by 10 the Free Software Foundation; either version 3 of the License, or 11 (at your option) any later version. 12 13 This program is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 GNU General Public License for more details. 17 18 You should have received a copy of the GNU General Public License 19 along with this program; if not, write to the Free Software 20 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, 21 MA 02110-1301, USA. */ 22 23 #include "sysdep.h" 24 #include "bfd.h" 25 #include "libbfd.h" 26 #include "elf-bfd.h" 27 #include "elf/d10v.h" 28 29 /* Use REL instead of RELA to save space. */ 30 #define USE_REL 1 31 32 static reloc_howto_type elf_d10v_howto_table[] = 33 { 34 /* This reloc does nothing. */ 35 HOWTO (R_D10V_NONE, /* Type. */ 36 0, /* Rightshift. */ 37 2, /* Size (0 = byte, 1 = short, 2 = long). */ 38 32, /* Bitsize. */ 39 FALSE, /* PC_relative. */ 40 0, /* Bitpos. */ 41 complain_overflow_dont,/* Complain_on_overflow. */ 42 bfd_elf_generic_reloc, /* Special_function. */ 43 "R_D10V_NONE", /* Name. */ 44 FALSE, /* Partial_inplace. */ 45 0, /* Src_mask. */ 46 0, /* Dst_mask. */ 47 FALSE), /* PCrel_offset. */ 48 49 /* An PC Relative 10-bit relocation, shifted by 2, right container. */ 50 HOWTO (R_D10V_10_PCREL_R, /* Type. */ 51 2, /* Rightshift. */ 52 2, /* Size (0 = byte, 1 = short, 2 = long). */ 53 8, /* Bitsize. */ 54 TRUE, /* PC_relative. */ 55 0, /* Bitpos. */ 56 complain_overflow_signed, /* Complain_on_overflow. */ 57 bfd_elf_generic_reloc, /* Special_function. */ 58 "R_D10V_10_PCREL_R", /* Name. */ 59 FALSE, /* Partial_inplace. */ 60 0xff, /* Src_mask. */ 61 0xff, /* Dst_mask. */ 62 TRUE), /* PCrel_offset. */ 63 64 /* An PC Relative 10-bit relocation, shifted by 2, left container. */ 65 HOWTO (R_D10V_10_PCREL_L, /* Type. */ 66 2, /* Rightshift. */ 67 2, /* Size (0 = byte, 1 = short, 2 = long). */ 68 8, /* Bitsize. */ 69 TRUE, /* PC_relative. */ 70 15, /* Bitpos. */ 71 complain_overflow_signed, /* Complain_on_overflow. */ 72 bfd_elf_generic_reloc, /* Special_function. */ 73 "R_D10V_10_PCREL_L", /* Name. */ 74 FALSE, /* Partial_inplace. */ 75 0x07f8000, /* Src_mask. */ 76 0x07f8000, /* Dst_mask. */ 77 TRUE), /* PCrel_offset. */ 78 79 /* A 16 bit absolute relocation. */ 80 HOWTO (R_D10V_16, /* Type. */ 81 0, /* Rightshift. */ 82 1, /* Size (0 = byte, 1 = short, 2 = long). */ 83 16, /* Bitsize. */ 84 FALSE, /* PC_relative. */ 85 0, /* Bitpos. */ 86 complain_overflow_dont,/* Complain_on_overflow. */ 87 bfd_elf_generic_reloc, /* Special_function. */ 88 "R_D10V_16", /* Name. */ 89 FALSE, /* Partial_inplace. */ 90 0xffff, /* Src_mask. */ 91 0xffff, /* Dst_mask. */ 92 FALSE), /* PCrel_offset. */ 93 94 /* An 18 bit absolute relocation, right shifted 2. */ 95 HOWTO (R_D10V_18, /* Type. */ 96 2, /* Rightshift. */ 97 1, /* Size (0 = byte, 1 = short, 2 = long). */ 98 16, /* Bitsize. */ 99 FALSE, /* PC_relative. */ 100 0, /* Bitpos. */ 101 complain_overflow_dont, /* Complain_on_overflow. */ 102 bfd_elf_generic_reloc, /* Special_function. */ 103 "R_D10V_18", /* Name. */ 104 FALSE, /* Partial_inplace. */ 105 0xffff, /* Src_mask. */ 106 0xffff, /* Dst_mask. */ 107 FALSE), /* PCrel_offset. */ 108 109 /* A relative 18 bit relocation, right shifted by 2. */ 110 HOWTO (R_D10V_18_PCREL, /* Type. */ 111 2, /* Rightshift. */ 112 2, /* Size (0 = byte, 1 = short, 2 = long). */ 113 16, /* Bitsize. */ 114 TRUE, /* PC_relative. */ 115 0, /* Bitpos. */ 116 complain_overflow_signed, /* Complain_on_overflow. */ 117 bfd_elf_generic_reloc, /* Special_function. */ 118 "R_D10V_18_PCREL", /* Name. */ 119 FALSE, /* Partial_inplace. */ 120 0xffff, /* Src_mask. */ 121 0xffff, /* Dst_mask. */ 122 TRUE), /* PCrel_offset. */ 123 124 /* A 32 bit absolute relocation. */ 125 HOWTO (R_D10V_32, /* Type. */ 126 0, /* Rightshift. */ 127 2, /* Size (0 = byte, 1 = short, 2 = long). */ 128 32, /* Bitsize. */ 129 FALSE, /* PC_relative. */ 130 0, /* Bitpos. */ 131 complain_overflow_dont,/* Complain_on_overflow. */ 132 bfd_elf_generic_reloc, /* Special_function. */ 133 "R_D10V_32", /* Name. */ 134 FALSE, /* Partial_inplace. */ 135 0xffffffff, /* Src_mask. */ 136 0xffffffff, /* Dst_mask. */ 137 FALSE), /* PCrel_offset. */ 138 139 /* GNU extension to record C++ vtable hierarchy. */ 140 HOWTO (R_D10V_GNU_VTINHERIT, /* Type. */ 141 0, /* Rightshift. */ 142 2, /* Size (0 = byte, 1 = short, 2 = long). */ 143 0, /* Bitsize. */ 144 FALSE, /* PC_relative. */ 145 0, /* Bitpos. */ 146 complain_overflow_dont,/* Complain_on_overflow. */ 147 NULL, /* Special_function. */ 148 "R_D10V_GNU_VTINHERIT",/* Name. */ 149 FALSE, /* Partial_inplace. */ 150 0, /* Src_mask. */ 151 0, /* Dst_mask. */ 152 FALSE), /* PCrel_offset. */ 153 154 /* GNU extension to record C++ vtable member usage. */ 155 HOWTO (R_D10V_GNU_VTENTRY, /* Type. */ 156 0, /* Rightshift. */ 157 2, /* Size (0 = byte, 1 = short, 2 = long). */ 158 0, /* Bitsize. */ 159 FALSE, /* PC_relative. */ 160 0, /* Bitpos. */ 161 complain_overflow_dont,/* Complain_on_overflow. */ 162 _bfd_elf_rel_vtable_reloc_fn, /* Special_function. */ 163 "R_D10V_GNU_VTENTRY", /* Name. */ 164 FALSE, /* Partial_inplace. */ 165 0, /* Src_mask. */ 166 0, /* Dst_mask. */ 167 FALSE), /* PCrel_offset. */ 168 }; 169 170 /* Map BFD reloc types to D10V ELF reloc types. */ 171 172 struct d10v_reloc_map 173 { 174 bfd_reloc_code_real_type bfd_reloc_val; 175 unsigned char elf_reloc_val; 176 }; 177 178 static const struct d10v_reloc_map d10v_reloc_map[] = 179 { 180 { BFD_RELOC_NONE, R_D10V_NONE, }, 181 { BFD_RELOC_D10V_10_PCREL_R, R_D10V_10_PCREL_R }, 182 { BFD_RELOC_D10V_10_PCREL_L, R_D10V_10_PCREL_L }, 183 { BFD_RELOC_16, R_D10V_16 }, 184 { BFD_RELOC_D10V_18, R_D10V_18 }, 185 { BFD_RELOC_D10V_18_PCREL, R_D10V_18_PCREL }, 186 { BFD_RELOC_32, R_D10V_32 }, 187 { BFD_RELOC_VTABLE_INHERIT, R_D10V_GNU_VTINHERIT }, 188 { BFD_RELOC_VTABLE_ENTRY, R_D10V_GNU_VTENTRY }, 189 }; 190 191 static reloc_howto_type * 192 bfd_elf32_bfd_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED, 193 bfd_reloc_code_real_type code) 194 { 195 unsigned int i; 196 197 for (i = 0; 198 i < sizeof (d10v_reloc_map) / sizeof (struct d10v_reloc_map); 199 i++) 200 if (d10v_reloc_map[i].bfd_reloc_val == code) 201 return &elf_d10v_howto_table[d10v_reloc_map[i].elf_reloc_val]; 202 203 return NULL; 204 } 205 206 static reloc_howto_type * 207 bfd_elf32_bfd_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED, 208 const char *r_name) 209 { 210 unsigned int i; 211 212 for (i = 0; 213 i < sizeof (elf_d10v_howto_table) / sizeof (elf_d10v_howto_table[0]); 214 i++) 215 if (elf_d10v_howto_table[i].name != NULL 216 && strcasecmp (elf_d10v_howto_table[i].name, r_name) == 0) 217 return &elf_d10v_howto_table[i]; 218 219 return NULL; 220 } 221 222 /* Set the howto pointer for an D10V ELF reloc. */ 223 224 static void 225 d10v_info_to_howto_rel (bfd *abfd ATTRIBUTE_UNUSED, 226 arelent *cache_ptr, 227 Elf_Internal_Rela *dst) 228 { 229 unsigned int r_type; 230 231 r_type = ELF32_R_TYPE (dst->r_info); 232 BFD_ASSERT (r_type < (unsigned int) R_D10V_max); 233 cache_ptr->howto = &elf_d10v_howto_table[r_type]; 234 } 235 236 static asection * 237 elf32_d10v_gc_mark_hook (asection *sec, 238 struct bfd_link_info *info, 239 Elf_Internal_Rela *rel, 240 struct elf_link_hash_entry *h, 241 Elf_Internal_Sym *sym) 242 { 243 if (h != NULL) 244 switch (ELF32_R_TYPE (rel->r_info)) 245 { 246 case R_D10V_GNU_VTINHERIT: 247 case R_D10V_GNU_VTENTRY: 248 return NULL; 249 } 250 251 return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym); 252 } 253 254 /* Look through the relocs for a section during the first phase. 255 Since we don't do .gots or .plts, we just need to consider the 256 virtual table relocs for gc. */ 257 258 static bfd_boolean 259 elf32_d10v_check_relocs (bfd *abfd, 260 struct bfd_link_info *info, 261 asection *sec, 262 const Elf_Internal_Rela *relocs) 263 { 264 Elf_Internal_Shdr *symtab_hdr; 265 struct elf_link_hash_entry **sym_hashes; 266 const Elf_Internal_Rela *rel; 267 const Elf_Internal_Rela *rel_end; 268 269 if (info->relocatable) 270 return TRUE; 271 272 symtab_hdr = &elf_tdata (abfd)->symtab_hdr; 273 sym_hashes = elf_sym_hashes (abfd); 274 275 rel_end = relocs + sec->reloc_count; 276 for (rel = relocs; rel < rel_end; rel++) 277 { 278 struct elf_link_hash_entry *h; 279 unsigned long r_symndx; 280 281 r_symndx = ELF32_R_SYM (rel->r_info); 282 if (r_symndx < symtab_hdr->sh_info) 283 h = NULL; 284 else 285 { 286 h = sym_hashes[r_symndx - symtab_hdr->sh_info]; 287 while (h->root.type == bfd_link_hash_indirect 288 || h->root.type == bfd_link_hash_warning) 289 h = (struct elf_link_hash_entry *) h->root.u.i.link; 290 } 291 292 switch (ELF32_R_TYPE (rel->r_info)) 293 { 294 /* This relocation describes the C++ object vtable hierarchy. 295 Reconstruct it for later use during GC. */ 296 case R_D10V_GNU_VTINHERIT: 297 if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset)) 298 return FALSE; 299 break; 300 301 /* This relocation describes which C++ vtable entries are actually 302 used. Record for later use during GC. */ 303 case R_D10V_GNU_VTENTRY: 304 BFD_ASSERT (h != NULL); 305 if (h != NULL 306 && !bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_offset)) 307 return FALSE; 308 break; 309 } 310 } 311 312 return TRUE; 313 } 314 315 static bfd_vma 316 extract_rel_addend (bfd *abfd, 317 bfd_byte *where, 318 reloc_howto_type *howto) 319 { 320 bfd_vma insn, val; 321 322 switch (howto->size) 323 { 324 case 0: 325 insn = bfd_get_8 (abfd, where); 326 break; 327 case 1: 328 insn = bfd_get_16 (abfd, where); 329 break; 330 case 2: 331 insn = bfd_get_32 (abfd, where); 332 break; 333 default: 334 abort (); 335 } 336 337 val = (insn & howto->dst_mask) >> howto->bitpos << howto->rightshift; 338 /* We should really be testing for signed addends here, but we don't 339 have that info directly in the howto. */ 340 if (howto->pc_relative) 341 { 342 bfd_vma sign; 343 sign = howto->dst_mask & (~howto->dst_mask >> 1 | ~(-(bfd_vma) 1 >> 1)); 344 sign = sign >> howto->bitpos << howto->rightshift; 345 val = (val ^ sign) - sign; 346 } 347 return val; 348 } 349 350 static void 351 insert_rel_addend (bfd *abfd, 352 bfd_byte *where, 353 reloc_howto_type *howto, 354 bfd_vma addend) 355 { 356 bfd_vma insn; 357 358 addend = (addend >> howto->rightshift << howto->bitpos) & howto->dst_mask; 359 insn = ~howto->dst_mask; 360 switch (howto->size) 361 { 362 case 0: 363 insn &= bfd_get_8 (abfd, where); 364 insn |= addend; 365 bfd_put_8 (abfd, insn, where); 366 break; 367 case 1: 368 insn &= bfd_get_16 (abfd, where); 369 insn |= addend; 370 bfd_put_16 (abfd, insn, where); 371 break; 372 case 2: 373 insn &= bfd_get_32 (abfd, where); 374 insn |= addend; 375 bfd_put_32 (abfd, insn, where); 376 break; 377 default: 378 abort (); 379 } 380 } 381 382 /* Relocate a D10V ELF section. */ 383 384 static bfd_boolean 385 elf32_d10v_relocate_section (bfd *output_bfd, 386 struct bfd_link_info *info, 387 bfd *input_bfd, 388 asection *input_section, 389 bfd_byte *contents, 390 Elf_Internal_Rela *relocs, 391 Elf_Internal_Sym *local_syms, 392 asection **local_sections) 393 { 394 Elf_Internal_Shdr *symtab_hdr; 395 struct elf_link_hash_entry **sym_hashes; 396 Elf_Internal_Rela *rel, *relend; 397 const char *name; 398 399 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr; 400 sym_hashes = elf_sym_hashes (input_bfd); 401 402 rel = relocs; 403 relend = relocs + input_section->reloc_count; 404 for (; rel < relend; rel++) 405 { 406 int r_type; 407 reloc_howto_type *howto; 408 unsigned long r_symndx; 409 Elf_Internal_Sym *sym; 410 asection *sec; 411 struct elf_link_hash_entry *h; 412 bfd_vma relocation; 413 bfd_reloc_status_type r; 414 415 r_symndx = ELF32_R_SYM (rel->r_info); 416 r_type = ELF32_R_TYPE (rel->r_info); 417 418 if (r_type == R_D10V_GNU_VTENTRY 419 || r_type == R_D10V_GNU_VTINHERIT) 420 continue; 421 422 howto = elf_d10v_howto_table + r_type; 423 h = NULL; 424 sym = NULL; 425 sec = NULL; 426 if (r_symndx < symtab_hdr->sh_info) 427 { 428 sym = local_syms + r_symndx; 429 sec = local_sections[r_symndx]; 430 relocation = (sec->output_section->vma 431 + sec->output_offset 432 + sym->st_value); 433 if (ELF_ST_TYPE (sym->st_info) == STT_SECTION 434 && ((sec->flags & SEC_MERGE) != 0 435 || (info->relocatable 436 && sec->output_offset != 0))) 437 { 438 bfd_vma addend; 439 bfd_byte *where = contents + rel->r_offset; 440 441 addend = extract_rel_addend (input_bfd, where, howto); 442 443 if (info->relocatable) 444 addend += sec->output_offset; 445 else 446 { 447 asection *msec = sec; 448 addend = _bfd_elf_rel_local_sym (output_bfd, sym, &msec, 449 addend); 450 addend -= relocation; 451 addend += msec->output_section->vma + msec->output_offset; 452 } 453 insert_rel_addend (input_bfd, where, howto, addend); 454 } 455 } 456 else 457 { 458 bfd_boolean unresolved_reloc, warned; 459 460 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel, 461 r_symndx, symtab_hdr, sym_hashes, 462 h, sec, relocation, 463 unresolved_reloc, warned); 464 } 465 466 if (sec != NULL && elf_discarded_section (sec)) 467 { 468 /* For relocs against symbols from removed linkonce sections, 469 or sections discarded by a linker script, we just want the 470 section contents zeroed. Avoid any special processing. */ 471 _bfd_clear_contents (howto, input_bfd, contents + rel->r_offset); 472 rel->r_info = 0; 473 rel->r_addend = 0; 474 continue; 475 } 476 477 if (info->relocatable) 478 continue; 479 480 if (h != NULL) 481 name = h->root.root.string; 482 else 483 { 484 name = (bfd_elf_string_from_elf_section 485 (input_bfd, symtab_hdr->sh_link, sym->st_name)); 486 if (name == NULL || *name == '\0') 487 name = bfd_section_name (input_bfd, sec); 488 } 489 490 r = _bfd_final_link_relocate (howto, input_bfd, input_section, 491 contents, rel->r_offset, 492 relocation, (bfd_vma) 0); 493 494 if (r != bfd_reloc_ok) 495 { 496 const char * msg = (const char *) 0; 497 498 switch (r) 499 { 500 case bfd_reloc_overflow: 501 if (!((*info->callbacks->reloc_overflow) 502 (info, (h ? &h->root : NULL), name, howto->name, 503 (bfd_vma) 0, input_bfd, input_section, 504 rel->r_offset))) 505 return FALSE; 506 break; 507 508 case bfd_reloc_undefined: 509 if (!((*info->callbacks->undefined_symbol) 510 (info, name, input_bfd, input_section, 511 rel->r_offset, TRUE))) 512 return FALSE; 513 break; 514 515 case bfd_reloc_outofrange: 516 msg = _("internal error: out of range error"); 517 goto common_error; 518 519 case bfd_reloc_notsupported: 520 msg = _("internal error: unsupported relocation error"); 521 goto common_error; 522 523 case bfd_reloc_dangerous: 524 msg = _("internal error: dangerous error"); 525 goto common_error; 526 527 default: 528 msg = _("internal error: unknown error"); 529 /* fall through */ 530 531 common_error: 532 if (!((*info->callbacks->warning) 533 (info, msg, name, input_bfd, input_section, 534 rel->r_offset))) 535 return FALSE; 536 break; 537 } 538 } 539 } 540 541 return TRUE; 542 } 543 #define ELF_ARCH bfd_arch_d10v 544 #define ELF_MACHINE_CODE EM_D10V 545 #define ELF_MACHINE_ALT1 EM_CYGNUS_D10V 546 #define ELF_MAXPAGESIZE 0x1000 547 548 #define TARGET_BIG_SYM bfd_elf32_d10v_vec 549 #define TARGET_BIG_NAME "elf32-d10v" 550 551 #define elf_info_to_howto 0 552 #define elf_info_to_howto_rel d10v_info_to_howto_rel 553 #define elf_backend_object_p 0 554 #define elf_backend_final_write_processing 0 555 #define elf_backend_gc_mark_hook elf32_d10v_gc_mark_hook 556 #define elf_backend_check_relocs elf32_d10v_check_relocs 557 #define elf_backend_relocate_section elf32_d10v_relocate_section 558 #define elf_backend_can_gc_sections 1 559 560 #include "elf32-target.h" 561