bfd/elf32-d10v.c

   1 /* D10V-specific support for 32-bit ELF
   2    Copyright (C) 1996-2020 Free Software Foundation, Inc.
   3    Contributed by Martin Hunt (hunt@cygnus.com).
   4
   5    This file is part of BFD, the Binary File Descriptor library.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  20    MA 02110-1301, USA.  */
  21
  22 #include "sysdep.h"
  23 #include "bfd.h"
  24 #include "libbfd.h"
  25 #include "elf-bfd.h"
  26 #include "elf/d10v.h"
  27
  28 /* Use REL instead of RELA to save space.  */
  29 #define USE_REL 1
  30
  31 static reloc_howto_type elf_d10v_howto_table[] =
  32 {
  33   /* This reloc does nothing.  */
  34   HOWTO (R_D10V_NONE,           /* Type.  */
  35          0,                     /* Rightshift.  */
  36          3,                     /* Size (0 = byte, 1 = short, 2 = long).  */
  37          0,                     /* Bitsize.  */
  38          FALSE,                 /* PC_relative.  */
  39          0,                     /* Bitpos.  */
  40          complain_overflow_dont,/* Complain_on_overflow.  */
  41          bfd_elf_generic_reloc, /* Special_function.  */
  42          "R_D10V_NONE",         /* Name.  */
  43          FALSE,                 /* Partial_inplace.  */
  44          0,                     /* Src_mask.  */
  45          0,                     /* Dst_mask.  */
  46          FALSE),                /* PCrel_offset.  */
  47
  48   /* An PC Relative 10-bit relocation, shifted by 2, right container.  */
  49   HOWTO (R_D10V_10_PCREL_R,     /* Type.  */
  50          2,                     /* Rightshift.  */
  51          2,                     /* Size (0 = byte, 1 = short, 2 = long).  */
  52          8,                     /* Bitsize.  */
  53          TRUE,                  /* PC_relative.  */
  54          0,                     /* Bitpos.  */
  55          complain_overflow_signed, /* Complain_on_overflow.  */
  56          bfd_elf_generic_reloc, /* Special_function.  */
  57          "R_D10V_10_PCREL_R",   /* Name.  */
  58          FALSE,                 /* Partial_inplace.  */
  59          0xff,                  /* Src_mask.  */
  60          0xff,                  /* Dst_mask.  */
  61          TRUE),                 /* PCrel_offset.  */
  62
  63   /* An PC Relative 10-bit relocation, shifted by 2, left container.  */
  64   HOWTO (R_D10V_10_PCREL_L,     /* Type.  */
  65          2,                     /* Rightshift.  */
  66          2,                     /* Size (0 = byte, 1 = short, 2 = long).  */
  67          8,                     /* Bitsize.  */
  68          TRUE,                  /* PC_relative.  */
  69          15,                    /* Bitpos.  */
  70          complain_overflow_signed, /* Complain_on_overflow.  */
  71          bfd_elf_generic_reloc, /* Special_function.  */
  72          "R_D10V_10_PCREL_L",   /* Name.  */
  73          FALSE,                 /* Partial_inplace.  */
  74          0x07f8000,             /* Src_mask.  */
  75          0x07f8000,             /* Dst_mask.  */
  76          TRUE),                 /* PCrel_offset.  */
  77
  78   /* A 16 bit absolute relocation.  */
  79   HOWTO (R_D10V_16,             /* Type.  */
  80          0,                     /* Rightshift.  */
  81          1,                     /* Size (0 = byte, 1 = short, 2 = long).  */
  82          16,                    /* Bitsize.  */
  83          FALSE,                 /* PC_relative.  */
  84          0,                     /* Bitpos.  */
  85          complain_overflow_dont,/* Complain_on_overflow.  */
  86          bfd_elf_generic_reloc, /* Special_function.  */
  87          "R_D10V_16",           /* Name.  */
  88          FALSE,                 /* Partial_inplace.  */
  89          0xffff,                /* Src_mask.  */
  90          0xffff,                /* Dst_mask.  */
  91          FALSE),                /* PCrel_offset.  */
  92
  93   /* An 18 bit absolute relocation, right shifted 2.  */
  94   HOWTO (R_D10V_18,             /* Type.  */
  95          2,                     /* Rightshift.  */
  96          1,                     /* Size (0 = byte, 1 = short, 2 = long).  */
  97          16,                    /* Bitsize.  */
  98          FALSE,                 /* PC_relative.  */
  99          0,                     /* Bitpos.  */
 100          complain_overflow_dont, /* Complain_on_overflow.  */
 101          bfd_elf_generic_reloc, /* Special_function.  */
 102          "R_D10V_18",           /* Name.  */
 103          FALSE,                 /* Partial_inplace.  */
 104          0xffff,                /* Src_mask.  */
 105          0xffff,                /* Dst_mask.  */
 106          FALSE),                /* PCrel_offset.  */
 107
 108   /* A relative 18 bit relocation, right shifted by 2.  */
 109   HOWTO (R_D10V_18_PCREL,       /* Type.  */
 110          2,                     /* Rightshift.  */
 111          2,                     /* Size (0 = byte, 1 = short, 2 = long).  */
 112          16,                    /* Bitsize.  */
 113          TRUE,                  /* PC_relative.  */
 114          0,                     /* Bitpos.  */
 115          complain_overflow_signed, /* Complain_on_overflow.  */
 116          bfd_elf_generic_reloc, /* Special_function.  */
 117          "R_D10V_18_PCREL",     /* Name.  */
 118          FALSE,                 /* Partial_inplace.  */
 119          0xffff,                /* Src_mask.  */
 120          0xffff,                /* Dst_mask.  */
 121          TRUE),                 /* PCrel_offset.  */
 122
 123   /* A 32 bit absolute relocation.  */
 124   HOWTO (R_D10V_32,             /* Type.  */
 125          0,                     /* Rightshift.  */
 126          2,                     /* Size (0 = byte, 1 = short, 2 = long).  */
 127          32,                    /* Bitsize.  */
 128          FALSE,                 /* PC_relative.  */
 129          0,                     /* Bitpos.  */
 130          complain_overflow_dont,/* Complain_on_overflow.  */
 131          bfd_elf_generic_reloc, /* Special_function.  */
 132          "R_D10V_32",           /* Name.  */
 133          FALSE,                 /* Partial_inplace.  */
 134          0xffffffff,            /* Src_mask.  */
 135          0xffffffff,            /* Dst_mask.  */
 136          FALSE),                /* PCrel_offset.  */
 137
 138   /* GNU extension to record C++ vtable hierarchy.  */
 139   HOWTO (R_D10V_GNU_VTINHERIT,  /* Type.  */
 140          0,                     /* Rightshift.  */
 141          2,                     /* Size (0 = byte, 1 = short, 2 = long).  */
 142          0,                     /* Bitsize.  */
 143          FALSE,                 /* PC_relative.  */
 144          0,                     /* Bitpos.  */
 145          complain_overflow_dont,/* Complain_on_overflow.  */
 146          NULL,                  /* Special_function.  */
 147          "R_D10V_GNU_VTINHERIT",/* Name.  */
 148          FALSE,                 /* Partial_inplace.  */
 149          0,                     /* Src_mask.  */
 150          0,                     /* Dst_mask.  */
 151          FALSE),                /* PCrel_offset.  */
 152
 153   /* GNU extension to record C++ vtable member usage.  */
 154   HOWTO (R_D10V_GNU_VTENTRY,    /* Type.  */
 155          0,                     /* Rightshift.  */
 156          2,                     /* Size (0 = byte, 1 = short, 2 = long).  */
 157          0,                     /* Bitsize.  */
 158          FALSE,                 /* PC_relative.  */
 159          0,                     /* Bitpos.  */
 160          complain_overflow_dont,/* Complain_on_overflow.  */
 161          _bfd_elf_rel_vtable_reloc_fn,  /* Special_function.  */
 162          "R_D10V_GNU_VTENTRY",  /* Name.  */
 163          FALSE,                 /* Partial_inplace.  */
 164          0,                     /* Src_mask.  */
 165          0,                     /* Dst_mask.  */
 166          FALSE),                /* PCrel_offset.  */
 167 };
 168
 169 /* Map BFD reloc types to D10V ELF reloc types.  */
 170
 171 struct d10v_reloc_map
 172 {
 173   bfd_reloc_code_real_type bfd_reloc_val;
 174   unsigned char elf_reloc_val;
 175 };
 176
 177 static const struct d10v_reloc_map d10v_reloc_map[] =
 178 {
 179   { BFD_RELOC_NONE, R_D10V_NONE, },
 180   { BFD_RELOC_D10V_10_PCREL_R, R_D10V_10_PCREL_R },
 181   { BFD_RELOC_D10V_10_PCREL_L, R_D10V_10_PCREL_L },
 182   { BFD_RELOC_16, R_D10V_16 },
 183   { BFD_RELOC_D10V_18, R_D10V_18 },
 184   { BFD_RELOC_D10V_18_PCREL, R_D10V_18_PCREL },
 185   { BFD_RELOC_32, R_D10V_32 },
 186   { BFD_RELOC_VTABLE_INHERIT, R_D10V_GNU_VTINHERIT },
 187   { BFD_RELOC_VTABLE_ENTRY, R_D10V_GNU_VTENTRY },
 188 };
 189
 190 static reloc_howto_type *
 191 bfd_elf32_bfd_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
 192                                  bfd_reloc_code_real_type code)
 193 {
 194   unsigned int i;
 195
 196   for (i = 0;
 197        i < sizeof (d10v_reloc_map) / sizeof (struct d10v_reloc_map);
 198        i++)
 199     if (d10v_reloc_map[i].bfd_reloc_val == code)
 200       return &elf_d10v_howto_table[d10v_reloc_map[i].elf_reloc_val];
 201
 202   return NULL;
 203 }
 204
 205 static reloc_howto_type *
 206 bfd_elf32_bfd_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
 207                                  const char *r_name)
 208 {
 209   unsigned int i;
 210
 211   for (i = 0;
 212        i < sizeof (elf_d10v_howto_table) / sizeof (elf_d10v_howto_table[0]);
 213        i++)
 214     if (elf_d10v_howto_table[i].name != NULL
 215         && strcasecmp (elf_d10v_howto_table[i].name, r_name) == 0)
 216       return &elf_d10v_howto_table[i];
 217
 218   return NULL;
 219 }
 220
 221 /* Set the howto pointer for an D10V ELF reloc.  */
 222
 223 static bfd_boolean
 224 d10v_info_to_howto_rel (bfd *abfd,
 225                         arelent *cache_ptr,
 226                         Elf_Internal_Rela *dst)
 227 {
 228   unsigned int r_type;
 229
 230   r_type = ELF32_R_TYPE (dst->r_info);
 231   if (r_type >= (unsigned int) R_D10V_max)
 232     {
 233       /* xgettext:c-format */
 234       _bfd_error_handler (_("%pB: unsupported relocation type %#x"),
 235                           abfd, r_type);
 236       bfd_set_error (bfd_error_bad_value);
 237       return FALSE;
 238     }
 239   cache_ptr->howto = &elf_d10v_howto_table[r_type];
 240   return TRUE;
 241 }
 242
 243 static asection *
 244 elf32_d10v_gc_mark_hook (asection *sec,
 245                          struct bfd_link_info *info,
 246                          Elf_Internal_Rela *rel,
 247                          struct elf_link_hash_entry *h,
 248                          Elf_Internal_Sym *sym)
 249 {
 250   if (h != NULL)
 251     switch (ELF32_R_TYPE (rel->r_info))
 252       {
 253       case R_D10V_GNU_VTINHERIT:
 254       case R_D10V_GNU_VTENTRY:
 255         return NULL;
 256       }
 257
 258   return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym);
 259 }
 260
 261 /* Look through the relocs for a section during the first phase.
 262    Since we don't do .gots or .plts, we just need to consider the
 263    virtual table relocs for gc.  */
 264
 265 static bfd_boolean
 266 elf32_d10v_check_relocs (bfd *abfd,
 267                          struct bfd_link_info *info,
 268                          asection *sec,
 269                          const Elf_Internal_Rela *relocs)
 270 {
 271   Elf_Internal_Shdr *symtab_hdr;
 272   struct elf_link_hash_entry **sym_hashes;
 273   const Elf_Internal_Rela *rel;
 274   const Elf_Internal_Rela *rel_end;
 275
 276   if (bfd_link_relocatable (info))
 277     return TRUE;
 278
 279   symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
 280   sym_hashes = elf_sym_hashes (abfd);
 281
 282   rel_end = relocs + sec->reloc_count;
 283   for (rel = relocs; rel < rel_end; rel++)
 284     {
 285       struct elf_link_hash_entry *h;
 286       unsigned long r_symndx;
 287
 288       r_symndx = ELF32_R_SYM (rel->r_info);
 289       if (r_symndx < symtab_hdr->sh_info)
 290         h = NULL;
 291       else
 292         {
 293           h = sym_hashes[r_symndx - symtab_hdr->sh_info];
 294           while (h->root.type == bfd_link_hash_indirect
 295                  || h->root.type == bfd_link_hash_warning)
 296             h = (struct elf_link_hash_entry *) h->root.u.i.link;
 297         }
 298
 299       switch (ELF32_R_TYPE (rel->r_info))
 300         {
 301         /* This relocation describes the C++ object vtable hierarchy.
 302            Reconstruct it for later use during GC.  */
 303         case R_D10V_GNU_VTINHERIT:
 304           if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
 305             return FALSE;
 306           break;
 307
 308         /* This relocation describes which C++ vtable entries are actually
 309            used.  Record for later use during GC.  */
 310         case R_D10V_GNU_VTENTRY:
 311           if (!bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_offset))
 312             return FALSE;
 313           break;
 314         }
 315     }
 316
 317   return TRUE;
 318 }
 319
 320 static bfd_vma
 321 extract_rel_addend (bfd *abfd,
 322                     bfd_byte *where,
 323                     reloc_howto_type *howto)
 324 {
 325   bfd_vma insn, val;
 326
 327   switch (howto->size)
 328     {
 329     case 0:
 330       insn = bfd_get_8 (abfd, where);
 331       break;
 332     case 1:
 333       insn = bfd_get_16 (abfd, where);
 334       break;
 335     case 2:
 336       insn = bfd_get_32 (abfd, where);
 337       break;
 338     default:
 339       abort ();
 340     }
 341
 342   val = (insn & howto->dst_mask) >> howto->bitpos << howto->rightshift;
 343   /* We should really be testing for signed addends here, but we don't
 344      have that info directly in the howto.  */
 345   if (howto->pc_relative)
 346     {
 347       bfd_vma sign;
 348       sign = howto->dst_mask & (~howto->dst_mask >> 1 | ~(-(bfd_vma) 1 >> 1));
 349       sign = sign >> howto->bitpos << howto->rightshift;
 350       val = (val ^ sign) - sign;
 351     }
 352   return val;
 353 }
 354
 355 static void
 356 insert_rel_addend (bfd *abfd,
 357                    bfd_byte *where,
 358                    reloc_howto_type *howto,
 359                    bfd_vma addend)
 360 {
 361   bfd_vma insn;
 362
 363   addend = (addend >> howto->rightshift << howto->bitpos) & howto->dst_mask;
 364   insn = ~howto->dst_mask;
 365   switch (howto->size)
 366     {
 367     case 0:
 368       insn &= bfd_get_8 (abfd, where);
 369       insn |= addend;
 370       bfd_put_8 (abfd, insn, where);
 371       break;
 372     case 1:
 373       insn &= bfd_get_16 (abfd, where);
 374       insn |= addend;
 375       bfd_put_16 (abfd, insn, where);
 376       break;
 377     case 2:
 378       insn &= bfd_get_32 (abfd, where);
 379       insn |= addend;
 380       bfd_put_32 (abfd, insn, where);
 381       break;
 382     default:
 383       abort ();
 384     }
 385 }
 386
 387 /* Relocate a D10V ELF section.  */
 388
 389 static bfd_boolean
 390 elf32_d10v_relocate_section (bfd *output_bfd,
 391                              struct bfd_link_info *info,
 392                              bfd *input_bfd,
 393                              asection *input_section,
 394                              bfd_byte *contents,
 395                              Elf_Internal_Rela *relocs,
 396                              Elf_Internal_Sym *local_syms,
 397                              asection **local_sections)
 398 {
 399   Elf_Internal_Shdr *symtab_hdr;
 400   struct elf_link_hash_entry **sym_hashes;
 401   Elf_Internal_Rela *rel, *relend;
 402   const char *name;
 403
 404   symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
 405   sym_hashes = elf_sym_hashes (input_bfd);
 406
 407   rel = relocs;
 408   relend = relocs + input_section->reloc_count;
 409   for (; rel < relend; rel++)
 410     {
 411       int r_type;
 412       reloc_howto_type *howto;
 413       unsigned long r_symndx;
 414       Elf_Internal_Sym *sym;
 415       asection *sec;
 416       struct elf_link_hash_entry *h;
 417       bfd_vma relocation;
 418       bfd_reloc_status_type r;
 419
 420       r_symndx = ELF32_R_SYM (rel->r_info);
 421       r_type = ELF32_R_TYPE (rel->r_info);
 422
 423       if (r_type == R_D10V_GNU_VTENTRY
 424           || r_type == R_D10V_GNU_VTINHERIT)
 425         continue;
 426
 427       howto = elf_d10v_howto_table + r_type;
 428       h = NULL;
 429       sym = NULL;
 430       sec = NULL;
 431       if (r_symndx < symtab_hdr->sh_info)
 432         {
 433           sym = local_syms + r_symndx;
 434           sec = local_sections[r_symndx];
 435           relocation = (sec->output_section->vma
 436                         + sec->output_offset
 437                         + sym->st_value);
 438           if (ELF_ST_TYPE (sym->st_info) == STT_SECTION
 439               && ((sec->flags & SEC_MERGE) != 0
 440                   || (bfd_link_relocatable (info)
 441                       && sec->output_offset != 0)))
 442             {
 443               bfd_vma addend;
 444               bfd_byte *where = contents + rel->r_offset;
 445
 446               addend = extract_rel_addend (input_bfd, where, howto);
 447
 448               if (bfd_link_relocatable (info))
 449                 addend += sec->output_offset;
 450               else
 451                 {
 452                   asection *msec = sec;
 453                   addend = _bfd_elf_rel_local_sym (output_bfd, sym, &msec,
 454                                                    addend);
 455                   addend -= relocation;
 456                   addend += msec->output_section->vma + msec->output_offset;
 457                 }
 458               insert_rel_addend (input_bfd, where, howto, addend);
 459             }
 460         }
 461       else
 462         {
 463           bfd_boolean unresolved_reloc, warned, ignored;
 464
 465           RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
 466                                    r_symndx, symtab_hdr, sym_hashes,
 467                                    h, sec, relocation,
 468                                    unresolved_reloc, warned, ignored);
 469         }
 470
 471       if (sec != NULL && discarded_section (sec))
 472         RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section,
 473                                          rel, 1, relend, howto, 0, contents);
 474
 475       if (bfd_link_relocatable (info))
 476         continue;
 477
 478       if (h != NULL)
 479         name = h->root.root.string;
 480       else
 481         {
 482           name = (bfd_elf_string_from_elf_section
 483                   (input_bfd, symtab_hdr->sh_link, sym->st_name));
 484           if (name == NULL || *name == '\0')
 485             name = bfd_section_name (sec);
 486         }
 487
 488       r = _bfd_final_link_relocate (howto, input_bfd, input_section,
 489                                     contents, rel->r_offset,
 490                                     relocation, (bfd_vma) 0);
 491
 492       if (r != bfd_reloc_ok)
 493         {
 494           const char * msg = (const char *) 0;
 495
 496           switch (r)
 497             {
 498             case bfd_reloc_overflow:
 499               (*info->callbacks->reloc_overflow)
 500                 (info, (h ? &h->root : NULL), name, howto->name,
 501                  (bfd_vma) 0, input_bfd, input_section, rel->r_offset);
 502               break;
 503
 504             case bfd_reloc_undefined:
 505               (*info->callbacks->undefined_symbol)
 506                 (info, name, input_bfd, input_section, rel->r_offset, TRUE);
 507               break;
 508
 509             case bfd_reloc_outofrange:
 510               msg = _("internal error: out of range error");
 511               goto common_error;
 512
 513             case bfd_reloc_notsupported:
 514               msg = _("internal error: unsupported relocation error");
 515               goto common_error;
 516
 517             case bfd_reloc_dangerous:
 518               msg = _("internal error: dangerous error");
 519               goto common_error;
 520
 521             default:
 522               msg = _("internal error: unknown error");
 523               /* fall through */
 524
 525             common_error:
 526               (*info->callbacks->warning) (info, msg, name, input_bfd,
 527                                            input_section, rel->r_offset);
 528               break;
 529             }
 530         }
 531     }
 532
 533   return TRUE;
 534 }
 535 #define ELF_ARCH                bfd_arch_d10v
 536 #define ELF_MACHINE_CODE        EM_D10V
 537 #define ELF_MACHINE_ALT1        EM_CYGNUS_D10V
 538 #define ELF_MAXPAGESIZE         0x1000
 539
 540 #define TARGET_BIG_SYM          d10v_elf32_vec
 541 #define TARGET_BIG_NAME         "elf32-d10v"
 542
 543 #define elf_info_to_howto                    NULL
 544 #define elf_info_to_howto_rel                d10v_info_to_howto_rel
 545 #define elf_backend_object_p                 0
 546 #define elf_backend_gc_mark_hook             elf32_d10v_gc_mark_hook
 547 #define elf_backend_check_relocs             elf32_d10v_check_relocs
 548 #define elf_backend_relocate_section         elf32_d10v_relocate_section
 549 #define elf_backend_can_gc_sections          1
 550
 551 #include "elf32-target.h"