bfd/elf32-d10v.c

   1 /* D10V-specific support for 32-bit ELF
   2    Copyright (C) 1996-2017 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 void
 224 d10v_info_to_howto_rel (bfd *abfd ATTRIBUTE_UNUSED,
 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 (_("%B: invalid D10V reloc number: %d"), abfd, r_type);
 235       r_type = 0;
 236     }
 237   cache_ptr->howto = &elf_d10v_howto_table[r_type];
 238 }
 239
 240 static asection *
 241 elf32_d10v_gc_mark_hook (asection *sec,
 242                          struct bfd_link_info *info,
 243                          Elf_Internal_Rela *rel,
 244                          struct elf_link_hash_entry *h,
 245                          Elf_Internal_Sym *sym)
 246 {
 247   if (h != NULL)
 248     switch (ELF32_R_TYPE (rel->r_info))
 249       {
 250       case R_D10V_GNU_VTINHERIT:
 251       case R_D10V_GNU_VTENTRY:
 252         return NULL;
 253       }
 254
 255   return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym);
 256 }
 257
 258 /* Look through the relocs for a section during the first phase.
 259    Since we don't do .gots or .plts, we just need to consider the
 260    virtual table relocs for gc.  */
 261
 262 static bfd_boolean
 263 elf32_d10v_check_relocs (bfd *abfd,
 264                          struct bfd_link_info *info,
 265                          asection *sec,
 266                          const Elf_Internal_Rela *relocs)
 267 {
 268   Elf_Internal_Shdr *symtab_hdr;
 269   struct elf_link_hash_entry **sym_hashes;
 270   const Elf_Internal_Rela *rel;
 271   const Elf_Internal_Rela *rel_end;
 272
 273   if (bfd_link_relocatable (info))
 274     return TRUE;
 275
 276   symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
 277   sym_hashes = elf_sym_hashes (abfd);
 278
 279   rel_end = relocs + sec->reloc_count;
 280   for (rel = relocs; rel < rel_end; rel++)
 281     {
 282       struct elf_link_hash_entry *h;
 283       unsigned long r_symndx;
 284
 285       r_symndx = ELF32_R_SYM (rel->r_info);
 286       if (r_symndx < symtab_hdr->sh_info)
 287         h = NULL;
 288       else
 289         {
 290           h = sym_hashes[r_symndx - symtab_hdr->sh_info];
 291           while (h->root.type == bfd_link_hash_indirect
 292                  || h->root.type == bfd_link_hash_warning)
 293             h = (struct elf_link_hash_entry *) h->root.u.i.link;
 294
 295           /* PR15323, ref flags aren't set for references in the same
 296              object.  */
 297           h->root.non_ir_ref_regular = 1;
 298         }
 299
 300       switch (ELF32_R_TYPE (rel->r_info))
 301         {
 302         /* This relocation describes the C++ object vtable hierarchy.
 303            Reconstruct it for later use during GC.  */
 304         case R_D10V_GNU_VTINHERIT:
 305           if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
 306             return FALSE;
 307           break;
 308
 309         /* This relocation describes which C++ vtable entries are actually
 310            used.  Record for later use during GC.  */
 311         case R_D10V_GNU_VTENTRY:
 312           BFD_ASSERT (h != NULL);
 313           if (h != NULL
 314               && !bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_offset))
 315             return FALSE;
 316           break;
 317         }
 318     }
 319
 320   return TRUE;
 321 }
 322
 323 static bfd_vma
 324 extract_rel_addend (bfd *abfd,
 325                     bfd_byte *where,
 326                     reloc_howto_type *howto)
 327 {
 328   bfd_vma insn, val;
 329
 330   switch (howto->size)
 331     {
 332     case 0:
 333       insn = bfd_get_8 (abfd, where);
 334       break;
 335     case 1:
 336       insn = bfd_get_16 (abfd, where);
 337       break;
 338     case 2:
 339       insn = bfd_get_32 (abfd, where);
 340       break;
 341     default:
 342       abort ();
 343     }
 344
 345   val = (insn & howto->dst_mask) >> howto->bitpos << howto->rightshift;
 346   /* We should really be testing for signed addends here, but we don't
 347      have that info directly in the howto.  */
 348   if (howto->pc_relative)
 349     {
 350       bfd_vma sign;
 351       sign = howto->dst_mask & (~howto->dst_mask >> 1 | ~(-(bfd_vma) 1 >> 1));
 352       sign = sign >> howto->bitpos << howto->rightshift;
 353       val = (val ^ sign) - sign;
 354     }
 355   return val;
 356 }
 357
 358 static void
 359 insert_rel_addend (bfd *abfd,
 360                    bfd_byte *where,
 361                    reloc_howto_type *howto,
 362                    bfd_vma addend)
 363 {
 364   bfd_vma insn;
 365
 366   addend = (addend >> howto->rightshift << howto->bitpos) & howto->dst_mask;
 367   insn = ~howto->dst_mask;
 368   switch (howto->size)
 369     {
 370     case 0:
 371       insn &= bfd_get_8 (abfd, where);
 372       insn |= addend;
 373       bfd_put_8 (abfd, insn, where);
 374       break;
 375     case 1:
 376       insn &= bfd_get_16 (abfd, where);
 377       insn |= addend;
 378       bfd_put_16 (abfd, insn, where);
 379       break;
 380     case 2:
 381       insn &= bfd_get_32 (abfd, where);
 382       insn |= addend;
 383       bfd_put_32 (abfd, insn, where);
 384       break;
 385     default:
 386       abort ();
 387     }
 388 }
 389
 390 /* Relocate a D10V ELF section.  */
 391
 392 static bfd_boolean
 393 elf32_d10v_relocate_section (bfd *output_bfd,
 394                              struct bfd_link_info *info,
 395                              bfd *input_bfd,
 396                              asection *input_section,
 397                              bfd_byte *contents,
 398                              Elf_Internal_Rela *relocs,
 399                              Elf_Internal_Sym *local_syms,
 400                              asection **local_sections)
 401 {
 402   Elf_Internal_Shdr *symtab_hdr;
 403   struct elf_link_hash_entry **sym_hashes;
 404   Elf_Internal_Rela *rel, *relend;
 405   const char *name;
 406
 407   symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
 408   sym_hashes = elf_sym_hashes (input_bfd);
 409
 410   rel = relocs;
 411   relend = relocs + input_section->reloc_count;
 412   for (; rel < relend; rel++)
 413     {
 414       int r_type;
 415       reloc_howto_type *howto;
 416       unsigned long r_symndx;
 417       Elf_Internal_Sym *sym;
 418       asection *sec;
 419       struct elf_link_hash_entry *h;
 420       bfd_vma relocation;
 421       bfd_reloc_status_type r;
 422
 423       r_symndx = ELF32_R_SYM (rel->r_info);
 424       r_type = ELF32_R_TYPE (rel->r_info);
 425
 426       if (r_type == R_D10V_GNU_VTENTRY
 427           || r_type == R_D10V_GNU_VTINHERIT)
 428         continue;
 429
 430       howto = elf_d10v_howto_table + r_type;
 431       h = NULL;
 432       sym = NULL;
 433       sec = NULL;
 434       if (r_symndx < symtab_hdr->sh_info)
 435         {
 436           sym = local_syms + r_symndx;
 437           sec = local_sections[r_symndx];
 438           relocation = (sec->output_section->vma
 439                         + sec->output_offset
 440                         + sym->st_value);
 441           if (ELF_ST_TYPE (sym->st_info) == STT_SECTION
 442               && ((sec->flags & SEC_MERGE) != 0
 443                   || (bfd_link_relocatable (info)
 444                       && sec->output_offset != 0)))
 445             {
 446               bfd_vma addend;
 447               bfd_byte *where = contents + rel->r_offset;
 448
 449               addend = extract_rel_addend (input_bfd, where, howto);
 450
 451               if (bfd_link_relocatable (info))
 452                 addend += sec->output_offset;
 453               else
 454                 {
 455                   asection *msec = sec;
 456                   addend = _bfd_elf_rel_local_sym (output_bfd, sym, &msec,
 457                                                    addend);
 458                   addend -= relocation;
 459                   addend += msec->output_section->vma + msec->output_offset;
 460                 }
 461               insert_rel_addend (input_bfd, where, howto, addend);
 462             }
 463         }
 464       else
 465         {
 466           bfd_boolean unresolved_reloc, warned, ignored;
 467
 468           RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
 469                                    r_symndx, symtab_hdr, sym_hashes,
 470                                    h, sec, relocation,
 471                                    unresolved_reloc, warned, ignored);
 472         }
 473
 474       if (sec != NULL && discarded_section (sec))
 475         RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section,
 476                                          rel, 1, relend, howto, 0, contents);
 477
 478       if (bfd_link_relocatable (info))
 479         continue;
 480
 481       if (h != NULL)
 482         name = h->root.root.string;
 483       else
 484         {
 485           name = (bfd_elf_string_from_elf_section
 486                   (input_bfd, symtab_hdr->sh_link, sym->st_name));
 487           if (name == NULL || *name == '\0')
 488             name = bfd_section_name (input_bfd, sec);
 489         }
 490
 491       r = _bfd_final_link_relocate (howto, input_bfd, input_section,
 492                                     contents, rel->r_offset,
 493                                     relocation, (bfd_vma) 0);
 494
 495       if (r != bfd_reloc_ok)
 496         {
 497           const char * msg = (const char *) 0;
 498
 499           switch (r)
 500             {
 501             case bfd_reloc_overflow:
 502               (*info->callbacks->reloc_overflow)
 503                 (info, (h ? &h->root : NULL), name, howto->name,
 504                  (bfd_vma) 0, input_bfd, input_section, rel->r_offset);
 505               break;
 506
 507             case bfd_reloc_undefined:
 508               (*info->callbacks->undefined_symbol)
 509                 (info, name, input_bfd, input_section, rel->r_offset, TRUE);
 510               break;
 511
 512             case bfd_reloc_outofrange:
 513               msg = _("internal error: out of range error");
 514               goto common_error;
 515
 516             case bfd_reloc_notsupported:
 517               msg = _("internal error: unsupported relocation error");
 518               goto common_error;
 519
 520             case bfd_reloc_dangerous:
 521               msg = _("internal error: dangerous error");
 522               goto common_error;
 523
 524             default:
 525               msg = _("internal error: unknown error");
 526               /* fall through */
 527
 528             common_error:
 529               (*info->callbacks->warning) (info, msg, name, input_bfd,
 530                                            input_section, rel->r_offset);
 531               break;
 532             }
 533         }
 534     }
 535
 536   return TRUE;
 537 }
 538 #define ELF_ARCH                bfd_arch_d10v
 539 #define ELF_MACHINE_CODE        EM_D10V
 540 #define ELF_MACHINE_ALT1        EM_CYGNUS_D10V
 541 #define ELF_MAXPAGESIZE         0x1000
 542
 543 #define TARGET_BIG_SYM          d10v_elf32_vec
 544 #define TARGET_BIG_NAME         "elf32-d10v"
 545
 546 #define elf_info_to_howto                    0
 547 #define elf_info_to_howto_rel                d10v_info_to_howto_rel
 548 #define elf_backend_object_p                 0
 549 #define elf_backend_final_write_processing   0
 550 #define elf_backend_gc_mark_hook             elf32_d10v_gc_mark_hook
 551 #define elf_backend_check_relocs             elf32_d10v_check_relocs
 552 #define elf_backend_relocate_section         elf32_d10v_relocate_section
 553 #define elf_backend_can_gc_sections          1
 554
 555 #include "elf32-target.h"