bfd/elf32-d10v.c

   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"