bfd/elf32-d10v.c

   1 /* D10V-specific support for 32-bit ELF
   2    Copyright 1996, 1998, 1999, 2000, 2001, 2002, 2003, 2004
   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, MA 02110-1301, USA.  */
  21
  22 #include "bfd.h"
  23 #include "sysdep.h"
  24 #include "libbfd.h"
  25 #include "elf-bfd.h"
  26 #include "elf/d10v.h"
  27
  28 static reloc_howto_type *bfd_elf32_bfd_reloc_type_lookup
  29   PARAMS ((bfd *abfd, bfd_reloc_code_real_type code));
  30 static void d10v_info_to_howto_rel
  31   PARAMS ((bfd *, arelent *, Elf_Internal_Rela *));
  32 static asection * elf32_d10v_gc_mark_hook
  33   PARAMS ((asection *, struct bfd_link_info *, Elf_Internal_Rela *,
  34            struct elf_link_hash_entry *, Elf_Internal_Sym *));
  35 static bfd_boolean elf32_d10v_gc_sweep_hook
  36   PARAMS ((bfd *, struct bfd_link_info *, asection *,
  37            const Elf_Internal_Rela *));
  38 static bfd_boolean elf32_d10v_check_relocs
  39   PARAMS ((bfd *, struct bfd_link_info *, asection *,
  40            const Elf_Internal_Rela *));
  41 static bfd_vma extract_rel_addend
  42   PARAMS ((bfd *, bfd_byte *, reloc_howto_type *));
  43 static void insert_rel_addend
  44   PARAMS ((bfd *, bfd_byte *, reloc_howto_type *, bfd_vma));
  45 static bfd_boolean elf32_d10v_relocate_section
  46   PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *,
  47            bfd_byte *, Elf_Internal_Rela *, Elf_Internal_Sym *,
  48            asection **));
  49
  50 /* Use REL instead of RELA to save space.  */
  51 #define USE_REL 1
  52
  53 static reloc_howto_type elf_d10v_howto_table[] =
  54   {
  55     /* This reloc does nothing.  */
  56     HOWTO (R_D10V_NONE,         /* type */
  57            0,                   /* rightshift */
  58            2,                   /* size (0 = byte, 1 = short, 2 = long) */
  59            32,                  /* bitsize */
  60            FALSE,               /* pc_relative */
  61            0,                   /* bitpos */
  62            complain_overflow_dont, /* complain_on_overflow */
  63            bfd_elf_generic_reloc, /* special_function */
  64            "R_D10V_NONE",       /* name */
  65            FALSE,               /* partial_inplace */
  66            0,                   /* src_mask */
  67            0,                   /* dst_mask */
  68            FALSE),              /* pcrel_offset */
  69
  70     /* An PC Relative 10-bit relocation, shifted by 2  */
  71     /* right container */
  72     HOWTO (R_D10V_10_PCREL_R,   /* type */
  73            2,                   /* rightshift */
  74            2,                   /* size (0 = byte, 1 = short, 2 = long) */
  75            7,                   /* bitsize */
  76            TRUE,                /* pc_relative */
  77            0,                   /* bitpos */
  78            complain_overflow_bitfield, /* complain_on_overflow */
  79            bfd_elf_generic_reloc, /* special_function */
  80            "R_D10V_10_PCREL_R", /* name */
  81            FALSE,               /* partial_inplace */
  82            0xff,                /* src_mask */
  83            0xff,                /* dst_mask */
  84            TRUE),               /* pcrel_offset */
  85
  86     /* An PC Relative 10-bit relocation, shifted by 2  */
  87     /* left container */
  88     HOWTO (R_D10V_10_PCREL_L,   /* type */
  89            2,                   /* rightshift */
  90            2,                   /* size (0 = byte, 1 = short, 2 = long) */
  91            7,                   /* bitsize */
  92            TRUE,                /* pc_relative */
  93            15,                  /* bitpos */
  94            complain_overflow_bitfield, /* complain_on_overflow */
  95            bfd_elf_generic_reloc, /* special_function */
  96            "R_D10V_10_PCREL_L", /* name */
  97            FALSE,               /* partial_inplace */
  98            0x07f8000,           /* src_mask */
  99            0x07f8000,           /* dst_mask */
 100            TRUE),               /* pcrel_offset */
 101
 102     /* A 16 bit absolute relocation */
 103     HOWTO (R_D10V_16,           /* type */
 104            0,                   /* rightshift */
 105            1,                   /* size (0 = byte, 1 = short, 2 = long) */
 106            16,                  /* bitsize */
 107            FALSE,               /* pc_relative */
 108            0,                   /* bitpos */
 109            complain_overflow_dont, /* complain_on_overflow */
 110            bfd_elf_generic_reloc, /* special_function */
 111            "R_D10V_16",         /* name */
 112            FALSE,               /* partial_inplace */
 113            0xffff,              /* src_mask */
 114            0xffff,              /* dst_mask */
 115            FALSE),              /* pcrel_offset */
 116
 117     /* An 18 bit absolute relocation, right shifted 2 */
 118     HOWTO (R_D10V_18,           /* type */
 119            2,                   /* rightshift */
 120            1,                   /* size (0 = byte, 1 = short, 2 = long) */
 121            16,                  /* bitsize */
 122            FALSE,               /* pc_relative */
 123            0,                   /* bitpos */
 124            complain_overflow_dont, /* complain_on_overflow */
 125            bfd_elf_generic_reloc, /* special_function */
 126            "R_D10V_18",         /* name */
 127            FALSE,               /* partial_inplace */
 128            0xffff,              /* src_mask */
 129            0xffff,              /* dst_mask */
 130            FALSE),              /* pcrel_offset */
 131
 132     /* A relative 18 bit relocation, right shifted by 2  */
 133     HOWTO (R_D10V_18_PCREL,     /* type */
 134            2,                   /* rightshift */
 135            2,                   /* size (0 = byte, 1 = short, 2 = long) */
 136            15,                  /* bitsize */
 137            TRUE,                /* pc_relative */
 138            0,                   /* bitpos */
 139            complain_overflow_bitfield, /* complain_on_overflow */
 140            bfd_elf_generic_reloc, /* special_function */
 141            "R_D10V_18_PCREL",   /* name */
 142            FALSE,               /* partial_inplace */
 143            0xffff,              /* src_mask */
 144            0xffff,              /* dst_mask */
 145            TRUE),                       /* pcrel_offset */
 146
 147     /* A 32 bit absolute relocation */
 148     HOWTO (R_D10V_32,           /* type */
 149            0,                   /* rightshift */
 150            2,                   /* size (0 = byte, 1 = short, 2 = long) */
 151            32,                  /* bitsize */
 152            FALSE,               /* pc_relative */
 153            0,                   /* bitpos */
 154            complain_overflow_dont, /* complain_on_overflow */
 155            bfd_elf_generic_reloc, /* special_function */
 156            "R_D10V_32",         /* name */
 157            FALSE,               /* partial_inplace */
 158            0xffffffff,          /* src_mask */
 159            0xffffffff,          /* dst_mask */
 160            FALSE),              /* pcrel_offset */
 161
 162     /* GNU extension to record C++ vtable hierarchy */
 163     HOWTO (R_D10V_GNU_VTINHERIT, /* type */
 164            0,                     /* rightshift */
 165            2,                     /* size (0 = byte, 1 = short, 2 = long) */
 166            0,                     /* bitsize */
 167            FALSE,                 /* pc_relative */
 168            0,                     /* bitpos */
 169            complain_overflow_dont, /* complain_on_overflow */
 170            NULL,                  /* special_function */
 171            "R_D10V_GNU_VTINHERIT", /* name */
 172            FALSE,                 /* partial_inplace */
 173            0,                     /* src_mask */
 174            0,                     /* dst_mask */
 175            FALSE),                /* pcrel_offset */
 176
 177     /* GNU extension to record C++ vtable member usage */
 178     HOWTO (R_D10V_GNU_VTENTRY,     /* type */
 179            0,                     /* rightshift */
 180            2,                     /* size (0 = byte, 1 = short, 2 = long) */
 181            0,                     /* bitsize */
 182            FALSE,                 /* pc_relative */
 183            0,                     /* bitpos */
 184            complain_overflow_dont, /* complain_on_overflow */
 185            _bfd_elf_rel_vtable_reloc_fn,  /* special_function */
 186            "R_D10V_GNU_VTENTRY",   /* name */
 187            FALSE,                 /* partial_inplace */
 188            0,                     /* src_mask */
 189            0,                     /* dst_mask */
 190            FALSE),                /* pcrel_offset */
 191   };
 192
 193 /* Map BFD reloc types to D10V ELF reloc types.  */
 194
 195 struct d10v_reloc_map
 196   {
 197     bfd_reloc_code_real_type bfd_reloc_val;
 198     unsigned char elf_reloc_val;
 199   };
 200
 201 static const struct d10v_reloc_map d10v_reloc_map[] =
 202   {
 203     { BFD_RELOC_NONE, R_D10V_NONE, },
 204     { BFD_RELOC_D10V_10_PCREL_R, R_D10V_10_PCREL_R },
 205     { BFD_RELOC_D10V_10_PCREL_L, R_D10V_10_PCREL_L },
 206     { BFD_RELOC_16, R_D10V_16 },
 207     { BFD_RELOC_D10V_18, R_D10V_18 },
 208     { BFD_RELOC_D10V_18_PCREL, R_D10V_18_PCREL },
 209     { BFD_RELOC_32, R_D10V_32 },
 210     { BFD_RELOC_VTABLE_INHERIT, R_D10V_GNU_VTINHERIT },
 211     { BFD_RELOC_VTABLE_ENTRY, R_D10V_GNU_VTENTRY },
 212   };
 213
 214 static reloc_howto_type *
 215 bfd_elf32_bfd_reloc_type_lookup (abfd, code)
 216      bfd *abfd ATTRIBUTE_UNUSED;
 217      bfd_reloc_code_real_type code;
 218 {
 219   unsigned int i;
 220
 221   for (i = 0;
 222        i < sizeof (d10v_reloc_map) / sizeof (struct d10v_reloc_map);
 223        i++)
 224     {
 225       if (d10v_reloc_map[i].bfd_reloc_val == code)
 226         return &elf_d10v_howto_table[d10v_reloc_map[i].elf_reloc_val];
 227     }
 228
 229   return NULL;
 230 }
 231
 232 /* Set the howto pointer for an D10V ELF reloc.  */
 233
 234 static void
 235 d10v_info_to_howto_rel (abfd, cache_ptr, dst)
 236      bfd *abfd ATTRIBUTE_UNUSED;
 237      arelent *cache_ptr;
 238      Elf_Internal_Rela *dst;
 239 {
 240   unsigned int r_type;
 241
 242   r_type = ELF32_R_TYPE (dst->r_info);
 243   BFD_ASSERT (r_type < (unsigned int) R_D10V_max);
 244   cache_ptr->howto = &elf_d10v_howto_table[r_type];
 245 }
 246
 247 static asection *
 248 elf32_d10v_gc_mark_hook (sec, info, rel, h, sym)
 249      asection *sec;
 250      struct bfd_link_info *info ATTRIBUTE_UNUSED;
 251      Elf_Internal_Rela *rel;
 252      struct elf_link_hash_entry *h;
 253      Elf_Internal_Sym *sym;
 254 {
 255   if (h != NULL)
 256     {
 257       switch (ELF32_R_TYPE (rel->r_info))
 258       {
 259       case R_D10V_GNU_VTINHERIT:
 260       case R_D10V_GNU_VTENTRY:
 261         break;
 262
 263       default:
 264         switch (h->root.type)
 265           {
 266           case bfd_link_hash_defined:
 267           case bfd_link_hash_defweak:
 268             return h->root.u.def.section;
 269
 270           case bfd_link_hash_common:
 271             return h->root.u.c.p->section;
 272
 273           default:
 274             break;
 275           }
 276        }
 277      }
 278    else
 279      return bfd_section_from_elf_index (sec->owner, sym->st_shndx);
 280
 281   return NULL;
 282 }
 283
 284 static bfd_boolean
 285 elf32_d10v_gc_sweep_hook (abfd, info, sec, relocs)
 286      bfd *abfd ATTRIBUTE_UNUSED;
 287      struct bfd_link_info *info ATTRIBUTE_UNUSED;
 288      asection *sec ATTRIBUTE_UNUSED;
 289      const Elf_Internal_Rela *relocs ATTRIBUTE_UNUSED;
 290 {
 291   /* we don't use got and plt entries for d10v */
 292   return TRUE;
 293 }
 294
 295 /* Look through the relocs for a section during the first phase.
 296    Since we don't do .gots or .plts, we just need to consider the
 297    virtual table relocs for gc.  */
 298
 299 static bfd_boolean
 300 elf32_d10v_check_relocs (abfd, info, sec, relocs)
 301      bfd *abfd;
 302      struct bfd_link_info *info;
 303      asection *sec;
 304      const Elf_Internal_Rela *relocs;
 305 {
 306   Elf_Internal_Shdr *symtab_hdr;
 307   struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
 308   const Elf_Internal_Rela *rel;
 309   const Elf_Internal_Rela *rel_end;
 310
 311   if (info->relocatable)
 312     return TRUE;
 313
 314   symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
 315   sym_hashes = elf_sym_hashes (abfd);
 316   sym_hashes_end = sym_hashes + symtab_hdr->sh_size/sizeof (Elf32_External_Sym);
 317   if (!elf_bad_symtab (abfd))
 318     sym_hashes_end -= symtab_hdr->sh_info;
 319
 320   rel_end = relocs + sec->reloc_count;
 321   for (rel = relocs; rel < rel_end; rel++)
 322     {
 323       struct elf_link_hash_entry *h;
 324       unsigned long r_symndx;
 325
 326       r_symndx = ELF32_R_SYM (rel->r_info);
 327       if (r_symndx < symtab_hdr->sh_info)
 328         h = NULL;
 329       else
 330         h = sym_hashes[r_symndx - symtab_hdr->sh_info];
 331
 332       switch (ELF32_R_TYPE (rel->r_info))
 333         {
 334         /* This relocation describes the C++ object vtable hierarchy.
 335            Reconstruct it for later use during GC.  */
 336         case R_D10V_GNU_VTINHERIT:
 337           if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
 338             return FALSE;
 339           break;
 340
 341         /* This relocation describes which C++ vtable entries are actually
 342            used.  Record for later use during GC.  */
 343         case R_D10V_GNU_VTENTRY:
 344           if (!bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_offset))
 345             return FALSE;
 346           break;
 347         }
 348     }
 349
 350   return TRUE;
 351 }
 352
 353 static bfd_vma
 354 extract_rel_addend (abfd, where, howto)
 355      bfd *abfd;
 356      bfd_byte *where;
 357      reloc_howto_type *howto;
 358 {
 359   bfd_vma insn, val;
 360
 361   switch (howto->size)
 362     {
 363     case 0:
 364       insn = bfd_get_8 (abfd, where);
 365       break;
 366     case 1:
 367       insn = bfd_get_16 (abfd, where);
 368       break;
 369     case 2:
 370       insn = bfd_get_32 (abfd, where);
 371       break;
 372     default:
 373       abort ();
 374     }
 375
 376   val = (insn & howto->dst_mask) >> howto->bitpos << howto->rightshift;
 377   /* We should really be testing for signed addends here, but we don't
 378      have that info directly in the howto.  */
 379   if (howto->pc_relative)
 380     {
 381       bfd_vma sign;
 382       sign = howto->dst_mask & (~howto->dst_mask >> 1 | ~(-(bfd_vma) 1 >> 1));
 383       sign = sign >> howto->bitpos << howto->rightshift;
 384       val = (val ^ sign) - sign;
 385     }
 386   return val;
 387 }
 388
 389 static void
 390 insert_rel_addend (abfd, where, howto, addend)
 391      bfd *abfd;
 392      bfd_byte *where;
 393      reloc_howto_type *howto;
 394      bfd_vma addend;
 395 {
 396   bfd_vma insn;
 397
 398   addend = (addend >> howto->rightshift << howto->bitpos) & howto->dst_mask;
 399   insn = ~howto->dst_mask;
 400   switch (howto->size)
 401     {
 402     case 0:
 403       insn &= bfd_get_8 (abfd, where);
 404       insn |= addend;
 405       bfd_put_8 (abfd, insn, where);
 406       break;
 407     case 1:
 408       insn &= bfd_get_16 (abfd, where);
 409       insn |= addend;
 410       bfd_put_16 (abfd, insn, where);
 411       break;
 412     case 2:
 413       insn &= bfd_get_32 (abfd, where);
 414       insn |= addend;
 415       bfd_put_32 (abfd, insn, where);
 416       break;
 417     default:
 418       abort ();
 419     }
 420 }
 421
 422 /* Relocate a D10V ELF section.  */
 423 static bfd_boolean
 424 elf32_d10v_relocate_section (output_bfd, info, input_bfd, input_section,
 425                             contents, relocs, local_syms, local_sections)
 426      bfd *output_bfd;
 427      struct bfd_link_info *info;
 428      bfd *input_bfd;
 429      asection *input_section;
 430      bfd_byte *contents;
 431      Elf_Internal_Rela *relocs;
 432      Elf_Internal_Sym *local_syms;
 433      asection **local_sections;
 434 {
 435   Elf_Internal_Shdr *symtab_hdr;
 436   struct elf_link_hash_entry **sym_hashes;
 437   Elf_Internal_Rela *rel, *relend;
 438   const char *name;
 439
 440   symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
 441   sym_hashes = elf_sym_hashes (input_bfd);
 442
 443   rel = relocs;
 444   relend = relocs + input_section->reloc_count;
 445   for (; rel < relend; rel++)
 446     {
 447       int r_type;
 448       reloc_howto_type *howto;
 449       unsigned long r_symndx;
 450       Elf_Internal_Sym *sym;
 451       asection *sec;
 452       struct elf_link_hash_entry *h;
 453       bfd_vma relocation;
 454       bfd_reloc_status_type r;
 455
 456       r_symndx = ELF32_R_SYM (rel->r_info);
 457       r_type = ELF32_R_TYPE (rel->r_info);
 458
 459       if (r_type == R_D10V_GNU_VTENTRY
 460           || r_type == R_D10V_GNU_VTINHERIT )
 461         continue;
 462
 463       howto = elf_d10v_howto_table + r_type;
 464
 465       if (info->relocatable)
 466         {
 467           bfd_vma val;
 468           bfd_byte *where;
 469
 470           /* This is a relocatable link.  We don't have to change
 471              anything, unless the reloc is against a section symbol,
 472              in which case we have to adjust according to where the
 473              section symbol winds up in the output section.  */
 474           if (r_symndx >= symtab_hdr->sh_info)
 475             continue;
 476
 477           sym = local_syms + r_symndx;
 478           if (ELF_ST_TYPE (sym->st_info) != STT_SECTION)
 479             continue;
 480
 481           sec = local_sections[r_symndx];
 482           val = sec->output_offset;
 483           if (val == 0)
 484             continue;
 485
 486           where = contents + rel->r_offset;
 487           val += extract_rel_addend (input_bfd, where, howto);
 488           insert_rel_addend (input_bfd, where, howto, val);
 489           continue;
 490         }
 491
 492       /* This is a final link.  */
 493       h = NULL;
 494       sym = NULL;
 495       sec = NULL;
 496       if (r_symndx < symtab_hdr->sh_info)
 497         {
 498           sym = local_syms + r_symndx;
 499           sec = local_sections[r_symndx];
 500           relocation = (sec->output_section->vma
 501                         + sec->output_offset
 502                         + sym->st_value);
 503           if ((sec->flags & SEC_MERGE)
 504               && ELF_ST_TYPE (sym->st_info) == STT_SECTION)
 505             {
 506               asection *msec;
 507               bfd_vma addend;
 508               bfd_byte *where = contents + rel->r_offset;
 509
 510               addend = extract_rel_addend (input_bfd, where, howto);
 511               msec = sec;
 512               addend = _bfd_elf_rel_local_sym (output_bfd, sym, &msec, addend);
 513               addend -= relocation;
 514               addend += msec->output_section->vma + msec->output_offset;
 515               insert_rel_addend (input_bfd, where, howto, addend);
 516             }
 517         }
 518       else
 519         {
 520           bfd_boolean unresolved_reloc, warned;
 521
 522           RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
 523                                    r_symndx, symtab_hdr, sym_hashes,
 524                                    h, sec, relocation,
 525                                    unresolved_reloc, warned);
 526         }
 527
 528       if (h != NULL)
 529         name = h->root.root.string;
 530       else
 531         {
 532           name = (bfd_elf_string_from_elf_section
 533                   (input_bfd, symtab_hdr->sh_link, sym->st_name));
 534           if (name == NULL || *name == '\0')
 535             name = bfd_section_name (input_bfd, sec);
 536         }
 537
 538       r = _bfd_final_link_relocate (howto, input_bfd, input_section,
 539                                     contents, rel->r_offset,
 540                                     relocation, (bfd_vma) 0);
 541
 542       if (r != bfd_reloc_ok)
 543         {
 544           const char * msg = (const char *) 0;
 545
 546           switch (r)
 547             {
 548             case bfd_reloc_overflow:
 549               if (!((*info->callbacks->reloc_overflow)
 550                     (info, (h ? &h->root : NULL), name, howto->name,
 551                      (bfd_vma) 0, input_bfd, input_section,
 552                      rel->r_offset)))
 553                 return FALSE;
 554               break;
 555
 556             case bfd_reloc_undefined:
 557               if (!((*info->callbacks->undefined_symbol)
 558                     (info, name, input_bfd, input_section,
 559                      rel->r_offset, TRUE)))
 560                 return FALSE;
 561               break;
 562
 563             case bfd_reloc_outofrange:
 564               msg = _("internal error: out of range error");
 565               goto common_error;
 566
 567             case bfd_reloc_notsupported:
 568               msg = _("internal error: unsupported relocation error");
 569               goto common_error;
 570
 571             case bfd_reloc_dangerous:
 572               msg = _("internal error: dangerous error");
 573               goto common_error;
 574
 575             default:
 576               msg = _("internal error: unknown error");
 577               /* fall through */
 578
 579             common_error:
 580               if (!((*info->callbacks->warning)
 581                     (info, msg, name, input_bfd, input_section,
 582                      rel->r_offset)))
 583                 return FALSE;
 584               break;
 585             }
 586         }
 587     }
 588
 589   return TRUE;
 590 }
 591 #define ELF_ARCH                bfd_arch_d10v
 592 #define ELF_MACHINE_CODE        EM_D10V
 593 #define ELF_MACHINE_ALT1        EM_CYGNUS_D10V
 594 #define ELF_MAXPAGESIZE         0x1000
 595
 596 #define TARGET_BIG_SYM          bfd_elf32_d10v_vec
 597 #define TARGET_BIG_NAME         "elf32-d10v"
 598
 599 #define elf_info_to_howto                    0
 600 #define elf_info_to_howto_rel                d10v_info_to_howto_rel
 601 #define elf_backend_object_p                 0
 602 #define elf_backend_final_write_processing   0
 603 #define elf_backend_gc_mark_hook             elf32_d10v_gc_mark_hook
 604 #define elf_backend_gc_sweep_hook            elf32_d10v_gc_sweep_hook
 605 #define elf_backend_check_relocs             elf32_d10v_check_relocs
 606 #define elf_backend_relocate_section         elf32_d10v_relocate_section
 607 #define elf_backend_can_gc_sections          1
 608
 609 #include "elf32-target.h"