1 /* DLX specific support for 32-bit ELF 2 Copyright 2002, 2003, 2004, 2005 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 2 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 "bfd.h" 22 #include "sysdep.h" 23 #include "libbfd.h" 24 #include "elf-bfd.h" 25 #include "elf/dlx.h" 26 27 #define USE_REL 1 28 29 #define bfd_elf32_bfd_reloc_type_lookup elf32_dlx_reloc_type_lookup 30 #define elf_info_to_howto elf32_dlx_info_to_howto 31 #define elf_info_to_howto_rel elf32_dlx_info_to_howto_rel 32 #define elf_backend_check_relocs elf32_dlx_check_relocs 33 34 /* The gas default behavior is not to preform the %hi modifier so that the 35 GNU assembler can have the lower 16 bits offset placed in the insn, BUT 36 we do like the gas to indicate it is %hi reloc type so when we in the link 37 loader phase we can have the corrected hi16 vale replace the buggous lo16 38 value that was placed there by gas. */ 39 40 static int skip_dlx_elf_hi16_reloc = 0; 41 42 extern int set_dlx_skip_hi16_flag (int); 43 44 int 45 set_dlx_skip_hi16_flag (int flag) 46 { 47 skip_dlx_elf_hi16_reloc = flag; 48 return flag; 49 } 50 51 static bfd_reloc_status_type 52 _bfd_dlx_elf_hi16_reloc (bfd *abfd, 53 arelent *reloc_entry, 54 asymbol *symbol, 55 void * data, 56 asection *input_section, 57 bfd *output_bfd, 58 char **error_message) 59 { 60 bfd_reloc_status_type ret; 61 bfd_vma relocation; 62 63 /* If the skip flag is set then we simply do the generic relocating, this 64 is more of a hack for dlx gas/gld, so we do not need to do the %hi/%lo 65 fixup like mips gld did. */ 66 if (skip_dlx_elf_hi16_reloc) 67 return bfd_elf_generic_reloc (abfd, reloc_entry, symbol, data, 68 input_section, output_bfd, error_message); 69 70 /* If we're relocating, and this an external symbol, we don't want 71 to change anything. */ 72 if (output_bfd != (bfd *) NULL 73 && (symbol->flags & BSF_SECTION_SYM) == 0 74 && reloc_entry->addend == 0) 75 { 76 reloc_entry->address += input_section->output_offset; 77 return bfd_reloc_ok; 78 } 79 80 ret = bfd_reloc_ok; 81 82 if (bfd_is_und_section (symbol->section) 83 && output_bfd == (bfd *) NULL) 84 ret = bfd_reloc_undefined; 85 86 relocation = (bfd_is_com_section (symbol->section)) ? 0 : symbol->value; 87 relocation += symbol->section->output_section->vma; 88 relocation += symbol->section->output_offset; 89 relocation += reloc_entry->addend; 90 relocation += bfd_get_16 (abfd, (bfd_byte *)data + reloc_entry->address); 91 92 if (reloc_entry->address > bfd_get_section_limit (abfd, input_section)) 93 return bfd_reloc_outofrange; 94 95 bfd_put_16 (abfd, (short)((relocation >> 16) & 0xFFFF), 96 (bfd_byte *)data + reloc_entry->address); 97 98 return ret; 99 } 100 101 /* ELF relocs are against symbols. If we are producing relocatable 102 output, and the reloc is against an external symbol, and nothing 103 has given us any additional addend, the resulting reloc will also 104 be against the same symbol. In such a case, we don't want to 105 change anything about the way the reloc is handled, since it will 106 all be done at final link time. Rather than put special case code 107 into bfd_perform_relocation, all the reloc types use this howto 108 function. It just short circuits the reloc if producing 109 relocatable output against an external symbol. */ 110 111 static bfd_reloc_status_type 112 elf32_dlx_relocate16 (bfd *abfd, 113 arelent *reloc_entry, 114 asymbol *symbol, 115 void * data, 116 asection *input_section, 117 bfd *output_bfd, 118 char **error_message ATTRIBUTE_UNUSED) 119 { 120 unsigned long insn, vallo, allignment; 121 int val; 122 123 /* HACK: I think this first condition is necessary when producing 124 relocatable output. After the end of HACK, the code is identical 125 to bfd_elf_generic_reloc(). I would _guess_ the first change 126 belongs there rather than here. martindo 1998-10-23. */ 127 128 if (skip_dlx_elf_hi16_reloc) 129 return bfd_elf_generic_reloc (abfd, reloc_entry, symbol, data, 130 input_section, output_bfd, error_message); 131 132 /* Check undefined section and undefined symbols. */ 133 if (bfd_is_und_section (symbol->section) 134 && output_bfd == (bfd *) NULL) 135 return bfd_reloc_undefined; 136 137 /* Can not support a long jump to sections other then .text. */ 138 if (strcmp (input_section->name, symbol->section->output_section->name) != 0) 139 { 140 fprintf (stderr, 141 "BFD Link Error: branch (PC rel16) to section (%s) not supported\n", 142 symbol->section->output_section->name); 143 return bfd_reloc_undefined; 144 } 145 146 insn = bfd_get_32 (abfd, (bfd_byte *)data + reloc_entry->address); 147 allignment = 1 << (input_section->output_section->alignment_power - 1); 148 vallo = insn & 0x0000FFFF; 149 150 if (vallo & 0x8000) 151 vallo = ~(vallo | 0xFFFF0000) + 1; 152 153 /* vallo points to the vma of next instruction. */ 154 vallo += (((unsigned long)(input_section->output_section->vma + 155 input_section->output_offset) + 156 allignment) & ~allignment); 157 158 /* val is the displacement (PC relative to next instruction). */ 159 val = (symbol->section->output_offset + 160 symbol->section->output_section->vma + 161 symbol->value) - vallo; 162 163 if (abs ((int) val) > 0x00007FFF) 164 return bfd_reloc_outofrange; 165 166 insn = (insn & 0xFFFF0000) | (val & 0x0000FFFF); 167 168 bfd_put_32 (abfd, insn, 169 (bfd_byte *) data + reloc_entry->address); 170 171 return bfd_reloc_ok; 172 } 173 174 static bfd_reloc_status_type 175 elf32_dlx_relocate26 (bfd *abfd, 176 arelent *reloc_entry, 177 asymbol *symbol, 178 void * data, 179 asection *input_section, 180 bfd *output_bfd, 181 char **error_message ATTRIBUTE_UNUSED) 182 { 183 unsigned long insn, vallo, allignment; 184 int val; 185 186 /* HACK: I think this first condition is necessary when producing 187 relocatable output. After the end of HACK, the code is identical 188 to bfd_elf_generic_reloc(). I would _guess_ the first change 189 belongs there rather than here. martindo 1998-10-23. */ 190 191 if (skip_dlx_elf_hi16_reloc) 192 return bfd_elf_generic_reloc (abfd, reloc_entry, symbol, data, 193 input_section, output_bfd, error_message); 194 195 /* Check undefined section and undefined symbols. */ 196 if (bfd_is_und_section (symbol->section) 197 && output_bfd == (bfd *) NULL) 198 return bfd_reloc_undefined; 199 200 /* Can not support a long jump to sections other then .text */ 201 if (strcmp (input_section->name, symbol->section->output_section->name) != 0) 202 { 203 fprintf (stderr, 204 "BFD Link Error: jump (PC rel26) to section (%s) not supported\n", 205 symbol->section->output_section->name); 206 return bfd_reloc_undefined; 207 } 208 209 insn = bfd_get_32 (abfd, (bfd_byte *)data + reloc_entry->address); 210 allignment = 1 << (input_section->output_section->alignment_power - 1); 211 vallo = insn & 0x03FFFFFF; 212 213 if (vallo & 0x03000000) 214 vallo = ~(vallo | 0xFC000000) + 1; 215 216 /* vallo is the vma for the next instruction. */ 217 vallo += (((unsigned long) (input_section->output_section->vma + 218 input_section->output_offset) + 219 allignment) & ~allignment); 220 221 /* val is the displacement (PC relative to next instruction). */ 222 val = (symbol->section->output_offset + 223 symbol->section->output_section->vma + symbol->value) 224 - vallo; 225 226 if (abs ((int) val) > 0x01FFFFFF) 227 return bfd_reloc_outofrange; 228 229 insn = (insn & 0xFC000000) | (val & 0x03FFFFFF); 230 bfd_put_32 (abfd, insn, 231 (bfd_byte *) data + reloc_entry->address); 232 233 return bfd_reloc_ok; 234 } 235 236 static reloc_howto_type dlx_elf_howto_table[]= 237 { 238 /* No relocation. */ 239 HOWTO (R_DLX_NONE, /* Type. */ 240 0, /* Rightshift. */ 241 0, /* size (0 = byte, 1 = short, 2 = long). */ 242 0, /* Bitsize. */ 243 FALSE, /* PC_relative. */ 244 0, /* Bitpos. */ 245 complain_overflow_dont,/* Complain_on_overflow. */ 246 bfd_elf_generic_reloc, /* Special_function. */ 247 "R_DLX_NONE", /* Name. */ 248 FALSE, /* Partial_inplace. */ 249 0, /* Src_mask. */ 250 0, /* Dst_mask. */ 251 FALSE), /* PCrel_offset. */ 252 253 /* 8 bit relocation. */ 254 HOWTO (R_DLX_RELOC_8, /* Type. */ 255 0, /* Rightshift. */ 256 0, /* Size (0 = byte, 1 = short, 2 = long). */ 257 8, /* Bitsize. */ 258 FALSE, /* PC_relative. */ 259 0, /* Bitpos. */ 260 complain_overflow_dont,/* Complain_on_overflow. */ 261 bfd_elf_generic_reloc, /* Special_function. */ 262 "R_DLX_RELOC_8", /* Name. */ 263 TRUE, /* Partial_inplace. */ 264 0xff, /* Src_mask. */ 265 0xff, /* Dst_mask. */ 266 FALSE), /* PCrel_offset. */ 267 268 /* 16 bit relocation. */ 269 HOWTO (R_DLX_RELOC_16, /* Type. */ 270 0, /* Rightshift. */ 271 1, /* Size (0 = byte, 1 = short, 2 = long). */ 272 16, /* Bitsize. */ 273 FALSE, /* PC_relative. */ 274 0, /* Bitpos. */ 275 complain_overflow_dont,/* Complain_on_overflow. */ 276 bfd_elf_generic_reloc, /* Special_function. */ 277 "R_DLX_RELOC_16", /* Name. */ 278 TRUE, /* Partial_inplace. */ 279 0xffff, /* Src_mask. */ 280 0xffff, /* Dst_mask. */ 281 FALSE), /* PCrel_offset. */ 282 283 /* 32 bit relocation. */ 284 HOWTO (R_DLX_RELOC_32, /* Type. */ 285 0, /* Rightshift. */ 286 2, /* Size (0 = byte, 1 = short, 2 = long). */ 287 32, /* Bitsize. */ 288 FALSE, /* PC_relative. */ 289 0, /* Bitpos. */ 290 complain_overflow_dont,/* Complain_on_overflow. */ 291 bfd_elf_generic_reloc, /* Special_function. */ 292 "R_DLX_RELOC_32", /* Name. */ 293 TRUE, /* Partial_inplace. */ 294 0xffffffff, /* Src_mask. */ 295 0xffffffff, /* Dst_mask. */ 296 FALSE), /* PCrel_offset. */ 297 298 /* GNU extension to record C++ vtable hierarchy. */ 299 HOWTO (R_DLX_GNU_VTINHERIT, /* Type. */ 300 0, /* Rightshift. */ 301 2, /* Size (0 = byte, 1 = short, 2 = long). */ 302 0, /* Bitsize. */ 303 FALSE, /* PC_relative. */ 304 0, /* Bitpos. */ 305 complain_overflow_dont,/* Complain_on_overflow. */ 306 NULL, /* Special_function. */ 307 "R_DLX_GNU_VTINHERIT", /* Name. */ 308 FALSE, /* Partial_inplace. */ 309 0, /* Src_mask. */ 310 0, /* Dst_mask. */ 311 FALSE), /* PCrel_offset. */ 312 313 /* GNU extension to record C++ vtable member usage. */ 314 HOWTO (R_DLX_GNU_VTENTRY, /* Type. */ 315 0, /* Rightshift. */ 316 2, /* Size (0 = byte, 1 = short, 2 = long). */ 317 0, /* Bitsize. */ 318 FALSE, /* PC_relative. */ 319 0, /* Bitpos. */ 320 complain_overflow_dont,/* Complain_on_overflow. */ 321 _bfd_elf_rel_vtable_reloc_fn,/* Special_function. */ 322 "R_DLX_GNU_VTENTRY", /* Name. */ 323 FALSE, /* Partial_inplace. */ 324 0, /* Src_mask. */ 325 0, /* Dst_mask. */ 326 FALSE) /* PCrel_offset. */ 327 }; 328 329 /* 16 bit offset for pc-relative branches. */ 330 static reloc_howto_type elf_dlx_gnu_rel16_s2 = 331 HOWTO (R_DLX_RELOC_16_PCREL, /* Type. */ 332 0, /* Rightshift. */ 333 1, /* Size (0 = byte, 1 = short, 2 = long). */ 334 16, /* Bitsize. */ 335 TRUE, /* PC_relative. */ 336 0, /* Bitpos. */ 337 complain_overflow_signed, /* Complain_on_overflow. */ 338 elf32_dlx_relocate16, /* Special_function. */ 339 "R_DLX_RELOC_16_PCREL",/* Name. */ 340 TRUE, /* Partial_inplace. */ 341 0xffff, /* Src_mask. */ 342 0xffff, /* Dst_mask. */ 343 TRUE); /* PCrel_offset. */ 344 345 /* 26 bit offset for pc-relative branches. */ 346 static reloc_howto_type elf_dlx_gnu_rel26_s2 = 347 HOWTO (R_DLX_RELOC_26_PCREL, /* Type. */ 348 0, /* Rightshift. */ 349 2, /* Size (0 = byte, 1 = short, 2 = long). */ 350 26, /* Bitsize. */ 351 TRUE, /* PC_relative. */ 352 0, /* Bitpos. */ 353 complain_overflow_dont,/* Complain_on_overflow. */ 354 elf32_dlx_relocate26, /* Special_function. */ 355 "R_DLX_RELOC_26_PCREL",/* Name. */ 356 TRUE, /* Partial_inplace. */ 357 0xffff, /* Src_mask. */ 358 0xffff, /* Dst_mask. */ 359 TRUE); /* PCrel_offset. */ 360 361 /* High 16 bits of symbol value. */ 362 static reloc_howto_type elf_dlx_reloc_16_hi = 363 HOWTO (R_DLX_RELOC_16_HI, /* Type. */ 364 16, /* Rightshift. */ 365 2, /* Size (0 = byte, 1 = short, 2 = long). */ 366 32, /* Bitsize. */ 367 FALSE, /* PC_relative. */ 368 0, /* Bitpos. */ 369 complain_overflow_dont,/* Complain_on_overflow. */ 370 _bfd_dlx_elf_hi16_reloc,/* Special_function. */ 371 "R_DLX_RELOC_16_HI", /* Name. */ 372 TRUE, /* Partial_inplace. */ 373 0xFFFF, /* Src_mask. */ 374 0xffff, /* Dst_mask. */ 375 FALSE); /* PCrel_offset. */ 376 377 /* Low 16 bits of symbol value. */ 378 static reloc_howto_type elf_dlx_reloc_16_lo = 379 HOWTO (R_DLX_RELOC_16_LO, /* Type. */ 380 0, /* Rightshift. */ 381 1, /* Size (0 = byte, 1 = short, 2 = long). */ 382 16, /* Bitsize. */ 383 FALSE, /* PC_relative. */ 384 0, /* Bitpos. */ 385 complain_overflow_dont,/* Complain_on_overflow. */ 386 bfd_elf_generic_reloc, /* Special_function. */ 387 "R_DLX_RELOC_16_LO", /* Name. */ 388 TRUE, /* Partial_inplace. */ 389 0xffff, /* Src_mask. */ 390 0xffff, /* Dst_mask. */ 391 FALSE); /* PCrel_offset. */ 392 393 /* A mapping from BFD reloc types to DLX ELF reloc types. 394 Stolen from elf32-mips.c. 395 396 More about this table - for dlx elf relocation we do not really 397 need this table, if we have a rtype defined in this table will 398 caused tc_gen_relocate confused and die on us, but if we remove 399 this table it will caused more problem, so for now simple solution 400 is to remove those entries which may cause problem. */ 401 struct elf_reloc_map 402 { 403 bfd_reloc_code_real_type bfd_reloc_val; 404 enum elf_dlx_reloc_type elf_reloc_val; 405 }; 406 407 static const struct elf_reloc_map dlx_reloc_map[] = 408 { 409 { BFD_RELOC_NONE, R_DLX_NONE }, 410 { BFD_RELOC_16, R_DLX_RELOC_16 }, 411 { BFD_RELOC_32, R_DLX_RELOC_32 }, 412 { BFD_RELOC_DLX_HI16_S, R_DLX_RELOC_16_HI }, 413 { BFD_RELOC_DLX_LO16, R_DLX_RELOC_16_LO }, 414 { BFD_RELOC_VTABLE_INHERIT, R_DLX_GNU_VTINHERIT }, 415 { BFD_RELOC_VTABLE_ENTRY, R_DLX_GNU_VTENTRY } 416 }; 417 418 /* Look through the relocs for a section during the first phase. 419 Since we don't do .gots or .plts, we just need to consider the 420 virtual table relocs for gc. */ 421 422 static bfd_boolean 423 elf32_dlx_check_relocs (bfd *abfd, 424 struct bfd_link_info *info, 425 asection *sec, 426 const Elf_Internal_Rela *relocs) 427 { 428 Elf_Internal_Shdr *symtab_hdr; 429 struct elf_link_hash_entry **sym_hashes, **sym_hashes_end; 430 const Elf_Internal_Rela *rel; 431 const Elf_Internal_Rela *rel_end; 432 433 if (info->relocatable) 434 return TRUE; 435 436 symtab_hdr = &elf_tdata (abfd)->symtab_hdr; 437 sym_hashes = elf_sym_hashes (abfd); 438 sym_hashes_end = sym_hashes + symtab_hdr->sh_size / sizeof (Elf32_External_Sym); 439 if (!elf_bad_symtab (abfd)) 440 sym_hashes_end -= symtab_hdr->sh_info; 441 442 rel_end = relocs + sec->reloc_count; 443 for (rel = relocs; rel < rel_end; rel++) 444 { 445 struct elf_link_hash_entry *h; 446 unsigned long r_symndx; 447 448 r_symndx = ELF32_R_SYM (rel->r_info); 449 if (r_symndx < symtab_hdr->sh_info) 450 h = NULL; 451 else 452 { 453 h = sym_hashes[r_symndx - symtab_hdr->sh_info]; 454 while (h->root.type == bfd_link_hash_indirect 455 || h->root.type == bfd_link_hash_warning) 456 h = (struct elf_link_hash_entry *) h->root.u.i.link; 457 } 458 459 switch (ELF32_R_TYPE (rel->r_info)) 460 { 461 /* This relocation describes the C++ object vtable hierarchy. 462 Reconstruct it for later use during GC. */ 463 case R_DLX_GNU_VTINHERIT: 464 if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset)) 465 return FALSE; 466 break; 467 468 /* This relocation describes which C++ vtable entries are actually 469 used. Record for later use during GC. */ 470 case R_DLX_GNU_VTENTRY: 471 if (!bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_addend)) 472 return FALSE; 473 break; 474 } 475 } 476 477 return TRUE; 478 } 479 480 /* Given a BFD reloc type, return a howto structure. */ 481 482 static reloc_howto_type * 483 elf32_dlx_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED, 484 bfd_reloc_code_real_type code) 485 { 486 unsigned int i; 487 488 for (i = 0; i < sizeof (dlx_reloc_map) / sizeof (struct elf_reloc_map); i++) 489 if (dlx_reloc_map[i].bfd_reloc_val == code) 490 return &dlx_elf_howto_table[(int) dlx_reloc_map[i].elf_reloc_val]; 491 492 switch (code) 493 { 494 default: 495 bfd_set_error (bfd_error_bad_value); 496 return NULL; 497 case BFD_RELOC_16_PCREL_S2: 498 return &elf_dlx_gnu_rel16_s2; 499 case BFD_RELOC_DLX_JMP26: 500 return &elf_dlx_gnu_rel26_s2; 501 case BFD_RELOC_HI16_S: 502 return &elf_dlx_reloc_16_hi; 503 case BFD_RELOC_LO16: 504 return &elf_dlx_reloc_16_lo; 505 } 506 } 507 508 static reloc_howto_type * 509 dlx_rtype_to_howto (unsigned int r_type) 510 { 511 switch (r_type) 512 { 513 case R_DLX_RELOC_16_PCREL: 514 return & elf_dlx_gnu_rel16_s2; 515 break; 516 case R_DLX_RELOC_26_PCREL: 517 return & elf_dlx_gnu_rel26_s2; 518 break; 519 case R_DLX_RELOC_16_HI: 520 return & elf_dlx_reloc_16_hi; 521 break; 522 case R_DLX_RELOC_16_LO: 523 return & elf_dlx_reloc_16_lo; 524 break; 525 526 default: 527 BFD_ASSERT (r_type < (unsigned int) R_DLX_max); 528 return & dlx_elf_howto_table[r_type]; 529 break; 530 } 531 } 532 533 static void 534 elf32_dlx_info_to_howto (bfd * abfd ATTRIBUTE_UNUSED, 535 arelent * cache_ptr ATTRIBUTE_UNUSED, 536 Elf_Internal_Rela * dst ATTRIBUTE_UNUSED) 537 { 538 abort (); 539 } 540 541 static void 542 elf32_dlx_info_to_howto_rel (bfd *abfd ATTRIBUTE_UNUSED, 543 arelent *cache_ptr, 544 Elf_Internal_Rela *dst) 545 { 546 unsigned int r_type; 547 548 r_type = ELF32_R_TYPE (dst->r_info); 549 cache_ptr->howto = dlx_rtype_to_howto (r_type); 550 return; 551 } 552 553 #define TARGET_BIG_SYM bfd_elf32_dlx_big_vec 554 #define TARGET_BIG_NAME "elf32-dlx" 555 #define ELF_ARCH bfd_arch_dlx 556 #define ELF_MACHINE_CODE EM_DLX 557 #define ELF_MAXPAGESIZE 1 /* FIXME: This number is wrong, It should be the page size in bytes. */ 558 559 #include "elf32-target.h" 560