bfd/elf32-d10v.c

   1 /* D10V-specific support for 32-bit ELF
   2    Copyright 1996, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005
   3    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 2 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 "bfd.h"
  24 #include "sysdep.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          7,                     /* Bitsize.  */
  54          TRUE,                  /* PC_relative.  */
  55          0,                     /* Bitpos.  */
  56          complain_overflow_bitfield, /* 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          7,                     /* Bitsize.  */
  69          TRUE,                  /* PC_relative.  */
  70          15,                    /* Bitpos.  */
  71          complain_overflow_bitfield, /* 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          15,                    /* Bitsize.  */
 114          TRUE,                  /* PC_relative.  */
 115          0,                     /* Bitpos.  */
 116          complain_overflow_bitfield, /* 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 /* Set the howto pointer for an D10V ELF reloc.  */
 207
 208 static void
 209 d10v_info_to_howto_rel (bfd *abfd ATTRIBUTE_UNUSED,
 210                         arelent *cache_ptr,
 211                         Elf_Internal_Rela *dst)
 212 {
 213   unsigned int r_type;
 214
 215   r_type = ELF32_R_TYPE (dst->r_info);
 216   BFD_ASSERT (r_type < (unsigned int) R_D10V_max);
 217   cache_ptr->howto = &elf_d10v_howto_table[r_type];
 218 }
 219
 220 static asection *
 221 elf32_d10v_gc_mark_hook (asection *sec,
 222                          struct bfd_link_info *info ATTRIBUTE_UNUSED,
 223                          Elf_Internal_Rela *rel,
 224                          struct elf_link_hash_entry *h,
 225                          Elf_Internal_Sym *sym)
 226 {
 227   if (h != NULL)
 228     {
 229       switch (ELF32_R_TYPE (rel->r_info))
 230       {
 231       case R_D10V_GNU_VTINHERIT:
 232       case R_D10V_GNU_VTENTRY:
 233         break;
 234
 235       default:
 236         switch (h->root.type)
 237           {
 238           case bfd_link_hash_defined:
 239           case bfd_link_hash_defweak:
 240             return h->root.u.def.section;
 241
 242           case bfd_link_hash_common:
 243             return h->root.u.c.p->section;
 244
 245           default:
 246             break;
 247           }
 248        }
 249      }
 250    else
 251      return bfd_section_from_elf_index (sec->owner, sym->st_shndx);
 252
 253   return NULL;
 254 }
 255
 256 static bfd_boolean
 257 elf32_d10v_gc_sweep_hook (bfd *abfd ATTRIBUTE_UNUSED,
 258                           struct bfd_link_info *info ATTRIBUTE_UNUSED,
 259                           asection *sec ATTRIBUTE_UNUSED,
 260                           const Elf_Internal_Rela *relocs ATTRIBUTE_UNUSED)
 261 {
 262   /* We don't use got and plt entries for d10v.  */
 263   return TRUE;
 264 }
 265
 266 /* Look through the relocs for a section during the first phase.
 267    Since we don't do .gots or .plts, we just need to consider the
 268    virtual table relocs for gc.  */
 269
 270 static bfd_boolean
 271 elf32_d10v_check_relocs (bfd *abfd,
 272                          struct bfd_link_info *info,
 273                          asection *sec,
 274                          const Elf_Internal_Rela *relocs)
 275 {
 276   Elf_Internal_Shdr *symtab_hdr;
 277   struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
 278   const Elf_Internal_Rela *rel;
 279   const Elf_Internal_Rela *rel_end;
 280
 281   if (info->relocatable)
 282     return TRUE;
 283
 284   symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
 285   sym_hashes = elf_sym_hashes (abfd);
 286   sym_hashes_end = sym_hashes + symtab_hdr->sh_size/sizeof (Elf32_External_Sym);
 287   if (!elf_bad_symtab (abfd))
 288     sym_hashes_end -= symtab_hdr->sh_info;
 289
 290   rel_end = relocs + sec->reloc_count;
 291   for (rel = relocs; rel < rel_end; rel++)
 292     {
 293       struct elf_link_hash_entry *h;
 294       unsigned long r_symndx;
 295
 296       r_symndx = ELF32_R_SYM (rel->r_info);
 297       if (r_symndx < symtab_hdr->sh_info)
 298         h = NULL;
 299       else
 300         {
 301           h = sym_hashes[r_symndx - symtab_hdr->sh_info];
 302           while (h->root.type == bfd_link_hash_indirect
 303                  || h->root.type == bfd_link_hash_warning)
 304             h = (struct elf_link_hash_entry *) h->root.u.i.link;
 305         }
 306
 307       switch (ELF32_R_TYPE (rel->r_info))
 308         {
 309         /* This relocation describes the C++ object vtable hierarchy.
 310            Reconstruct it for later use during GC.  */
 311         case R_D10V_GNU_VTINHERIT:
 312           if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
 313             return FALSE;
 314           break;
 315
 316         /* This relocation describes which C++ vtable entries are actually
 317            used.  Record for later use during GC.  */
 318         case R_D10V_GNU_VTENTRY:
 319           if (!bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_offset))
 320             return FALSE;
 321           break;
 322         }
 323     }
 324
 325   return TRUE;
 326 }
 327
 328 static bfd_vma
 329 extract_rel_addend (bfd *abfd,
 330                     bfd_byte *where,
 331                     reloc_howto_type *howto)
 332 {
 333   bfd_vma insn, val;
 334
 335   switch (howto->size)
 336     {
 337     case 0:
 338       insn = bfd_get_8 (abfd, where);
 339       break;
 340     case 1:
 341       insn = bfd_get_16 (abfd, where);
 342       break;
 343     case 2:
 344       insn = bfd_get_32 (abfd, where);
 345       break;
 346     default:
 347       abort ();
 348     }
 349
 350   val = (insn & howto->dst_mask) >> howto->bitpos << howto->rightshift;
 351   /* We should really be testing for signed addends here, but we don't
 352      have that info directly in the howto.  */
 353   if (howto->pc_relative)
 354     {
 355       bfd_vma sign;
 356       sign = howto->dst_mask & (~howto->dst_mask >> 1 | ~(-(bfd_vma) 1 >> 1));
 357       sign = sign >> howto->bitpos << howto->rightshift;
 358       val = (val ^ sign) - sign;
 359     }
 360   return val;
 361 }
 362
 363 static void
 364 insert_rel_addend (bfd *abfd,
 365                    bfd_byte *where,
 366                    reloc_howto_type *howto,
 367                    bfd_vma addend)
 368 {
 369   bfd_vma insn;
 370
 371   addend = (addend >> howto->rightshift << howto->bitpos) & howto->dst_mask;
 372   insn = ~howto->dst_mask;
 373   switch (howto->size)
 374     {
 375     case 0:
 376       insn &= bfd_get_8 (abfd, where);
 377       insn |= addend;
 378       bfd_put_8 (abfd, insn, where);
 379       break;
 380     case 1:
 381       insn &= bfd_get_16 (abfd, where);
 382       insn |= addend;
 383       bfd_put_16 (abfd, insn, where);
 384       break;
 385     case 2:
 386       insn &= bfd_get_32 (abfd, where);
 387       insn |= addend;
 388       bfd_put_32 (abfd, insn, where);
 389       break;
 390     default:
 391       abort ();
 392     }
 393 }
 394
 395 /* Relocate a D10V ELF section.  */
 396
 397 static bfd_boolean
 398 elf32_d10v_relocate_section (bfd *output_bfd,
 399                              struct bfd_link_info *info,
 400                              bfd *input_bfd,
 401                              asection *input_section,
 402                              bfd_byte *contents,
 403                              Elf_Internal_Rela *relocs,
 404                              Elf_Internal_Sym *local_syms,
 405                              asection **local_sections)
 406 {
 407   Elf_Internal_Shdr *symtab_hdr;
 408   struct elf_link_hash_entry **sym_hashes;
 409   Elf_Internal_Rela *rel, *relend;
 410   const char *name;
 411
 412   symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
 413   sym_hashes = elf_sym_hashes (input_bfd);
 414
 415   rel = relocs;
 416   relend = relocs + input_section->reloc_count;
 417   for (; rel < relend; rel++)
 418     {
 419       int r_type;
 420       reloc_howto_type *howto;
 421       unsigned long r_symndx;
 422       Elf_Internal_Sym *sym;
 423       asection *sec;
 424       struct elf_link_hash_entry *h;
 425       bfd_vma relocation;
 426       bfd_reloc_status_type r;
 427
 428       r_symndx = ELF32_R_SYM (rel->r_info);
 429       r_type = ELF32_R_TYPE (rel->r_info);
 430
 431       if (r_type == R_D10V_GNU_VTENTRY
 432           || r_type == R_D10V_GNU_VTINHERIT)
 433         continue;
 434
 435       howto = elf_d10v_howto_table + r_type;
 436
 437       if (info->relocatable)
 438         {
 439           bfd_vma val;
 440           bfd_byte *where;
 441
 442           /* This is a relocatable link.  We don't have to change
 443              anything, unless the reloc is against a section symbol,
 444              in which case we have to adjust according to where the
 445              section symbol winds up in the output section.  */
 446           if (r_symndx >= symtab_hdr->sh_info)
 447             continue;
 448
 449           sym = local_syms + r_symndx;
 450           if (ELF_ST_TYPE (sym->st_info) != STT_SECTION)
 451             continue;
 452
 453           sec = local_sections[r_symndx];
 454           val = sec->output_offset;
 455           if (val == 0)
 456             continue;
 457
 458           where = contents + rel->r_offset;
 459           val += extract_rel_addend (input_bfd, where, howto);
 460           insert_rel_addend (input_bfd, where, howto, val);
 461           continue;
 462         }
 463
 464       /* This is a final link.  */
 465       h = NULL;
 466       sym = NULL;
 467       sec = NULL;
 468       if (r_symndx < symtab_hdr->sh_info)
 469         {
 470           sym = local_syms + r_symndx;
 471           sec = local_sections[r_symndx];
 472           relocation = (sec->output_section->vma
 473                         + sec->output_offset
 474                         + sym->st_value);
 475           if ((sec->flags & SEC_MERGE)
 476               && ELF_ST_TYPE (sym->st_info) == STT_SECTION)
 477             {
 478               asection *msec;
 479               bfd_vma addend;
 480               bfd_byte *where = contents + rel->r_offset;
 481
 482               addend = extract_rel_addend (input_bfd, where, howto);
 483               msec = sec;
 484               addend = _bfd_elf_rel_local_sym (output_bfd, sym, &msec, addend);
 485               addend -= relocation;
 486               addend += msec->output_section->vma + msec->output_offset;
 487               insert_rel_addend (input_bfd, where, howto, addend);
 488             }
 489         }
 490       else
 491         {
 492           bfd_boolean unresolved_reloc, warned;
 493
 494           RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
 495                                    r_symndx, symtab_hdr, sym_hashes,
 496                                    h, sec, relocation,
 497                                    unresolved_reloc, warned);
 498         }
 499
 500       if (h != NULL)
 501         name = h->root.root.string;
 502       else
 503         {
 504           name = (bfd_elf_string_from_elf_section
 505                   (input_bfd, symtab_hdr->sh_link, sym->st_name));
 506           if (name == NULL || *name == '\0')
 507             name = bfd_section_name (input_bfd, sec);
 508         }
 509
 510       r = _bfd_final_link_relocate (howto, input_bfd, input_section,
 511                                     contents, rel->r_offset,
 512                                     relocation, (bfd_vma) 0);
 513
 514       if (r != bfd_reloc_ok)
 515         {
 516           const char * msg = (const char *) 0;
 517
 518           switch (r)
 519             {
 520             case bfd_reloc_overflow:
 521               if (!((*info->callbacks->reloc_overflow)
 522                     (info, (h ? &h->root : NULL), name, howto->name,
 523                      (bfd_vma) 0, input_bfd, input_section,
 524                      rel->r_offset)))
 525                 return FALSE;
 526               break;
 527
 528             case bfd_reloc_undefined:
 529               if (!((*info->callbacks->undefined_symbol)
 530                     (info, name, input_bfd, input_section,
 531                      rel->r_offset, TRUE)))
 532                 return FALSE;
 533               break;
 534
 535             case bfd_reloc_outofrange:
 536               msg = _("internal error: out of range error");
 537               goto common_error;
 538
 539             case bfd_reloc_notsupported:
 540               msg = _("internal error: unsupported relocation error");
 541               goto common_error;
 542
 543             case bfd_reloc_dangerous:
 544               msg = _("internal error: dangerous error");
 545               goto common_error;
 546
 547             default:
 548               msg = _("internal error: unknown error");
 549               /* fall through */
 550
 551             common_error:
 552               if (!((*info->callbacks->warning)
 553                     (info, msg, name, input_bfd, input_section,
 554                      rel->r_offset)))
 555                 return FALSE;
 556               break;
 557             }
 558         }
 559     }
 560
 561   return TRUE;
 562 }
 563 #define ELF_ARCH                bfd_arch_d10v
 564 #define ELF_MACHINE_CODE        EM_D10V
 565 #define ELF_MACHINE_ALT1        EM_CYGNUS_D10V
 566 #define ELF_MAXPAGESIZE         0x1000
 567
 568 #define TARGET_BIG_SYM          bfd_elf32_d10v_vec
 569 #define TARGET_BIG_NAME         "elf32-d10v"
 570
 571 #define elf_info_to_howto                    0
 572 #define elf_info_to_howto_rel                d10v_info_to_howto_rel
 573 #define elf_backend_object_p                 0
 574 #define elf_backend_final_write_processing   0
 575 #define elf_backend_gc_mark_hook             elf32_d10v_gc_mark_hook
 576 #define elf_backend_gc_sweep_hook            elf32_d10v_gc_sweep_hook
 577 #define elf_backend_check_relocs             elf32_d10v_check_relocs
 578 #define elf_backend_relocate_section         elf32_d10v_relocate_section
 579 #define elf_backend_can_gc_sections          1
 580
 581 #include "elf32-target.h"