bfd/elf32-moxie.c

   1 /* moxie-specific support for 32-bit ELF.
   2    Copyright (C) 2009-2016 Free Software Foundation, Inc.
   3
   4    Copied from elf32-fr30.c which is..
   5    Copyright (C) 1998-2016 Free Software Foundation, Inc.
   6
   7    This file is part of BFD, the Binary File Descriptor library.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program; if not, write to the Free Software
  21    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  22    MA 02110-1301, USA.  */
  23
  24 #include "sysdep.h"
  25 #include "bfd.h"
  26 #include "libbfd.h"
  27 #include "elf-bfd.h"
  28 #include "elf/moxie.h"
  29
  30 /* Forward declarations.  */
  31
  32 static reloc_howto_type moxie_elf_howto_table [] =
  33 {
  34   /* This reloc does nothing.  */
  35   HOWTO (R_MOXIE_NONE,          /* type */
  36          0,                     /* rightshift */
  37          3,                     /* size (0 = byte, 1 = short, 2 = long) */
  38          0,                     /* bitsize */
  39          FALSE,                 /* pc_relative */
  40          0,                     /* bitpos */
  41          complain_overflow_dont, /* complain_on_overflow */
  42          bfd_elf_generic_reloc, /* special_function */
  43          "R_MOXIE_NONE",                /* name */
  44          FALSE,                 /* partial_inplace */
  45          0,                     /* src_mask */
  46          0,                     /* dst_mask */
  47          FALSE),                /* pcrel_offset */
  48
  49   /* A 32 bit absolute relocation.  */
  50   HOWTO (R_MOXIE_32,            /* type */
  51          0,                     /* rightshift */
  52          2,                     /* size (0 = byte, 1 = short, 2 = long) */
  53          32,                    /* bitsize */
  54          FALSE,                 /* pc_relative */
  55          0,                     /* bitpos */
  56          complain_overflow_bitfield, /* complain_on_overflow */
  57          bfd_elf_generic_reloc, /* special_function */
  58          "R_MOXIE_32",          /* name */
  59          FALSE,                 /* partial_inplace */
  60          0x00000000,            /* src_mask */
  61          0xffffffff,            /* dst_mask */
  62          FALSE),                /* pcrel_offset */
  63
  64   /* A 10 bit PC-relative relocation.  */
  65   HOWTO (R_MOXIE_PCREL10,       /* type.  */
  66          1,                     /* rightshift.  */
  67          1,                     /* size (0 = byte, 1 = short, 2 = long).  */
  68          10,                    /* bitsize.  */
  69          TRUE,                  /* pc_relative.  */
  70          0,                     /* bitpos.  */
  71          complain_overflow_signed, /* complain_on_overflow.  */
  72          bfd_elf_generic_reloc, /* special_function.  */
  73          "R_MOXIE_PCREL10",             /* name.  */
  74          FALSE,                 /* partial_inplace.  */
  75          0,                     /* src_mask.  */
  76          0x000003FF,            /* dst_mask.  */
  77          TRUE),                 /* pcrel_offset.  */
  78 };
  79 \f
  80 /* Map BFD reloc types to MOXIE ELF reloc types.  */
  81
  82 struct moxie_reloc_map
  83 {
  84   bfd_reloc_code_real_type bfd_reloc_val;
  85   unsigned int moxie_reloc_val;
  86 };
  87
  88 static const struct moxie_reloc_map moxie_reloc_map [] =
  89 {
  90   { BFD_RELOC_NONE,            R_MOXIE_NONE },
  91   { BFD_RELOC_32,              R_MOXIE_32 },
  92   { BFD_RELOC_MOXIE_10_PCREL,  R_MOXIE_PCREL10 },
  93 };
  94
  95 static reloc_howto_type *
  96 moxie_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
  97                          bfd_reloc_code_real_type code)
  98 {
  99   unsigned int i;
 100
 101   for (i = sizeof (moxie_reloc_map) / sizeof (moxie_reloc_map[0]);
 102        i--;)
 103     if (moxie_reloc_map [i].bfd_reloc_val == code)
 104       return & moxie_elf_howto_table [moxie_reloc_map[i].moxie_reloc_val];
 105
 106   return NULL;
 107 }
 108
 109 static reloc_howto_type *
 110 moxie_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED, const char *r_name)
 111 {
 112   unsigned int i;
 113
 114   for (i = 0;
 115        i < sizeof (moxie_elf_howto_table) / sizeof (moxie_elf_howto_table[0]);
 116        i++)
 117     if (moxie_elf_howto_table[i].name != NULL
 118         && strcasecmp (moxie_elf_howto_table[i].name, r_name) == 0)
 119       return &moxie_elf_howto_table[i];
 120
 121   return NULL;
 122 }
 123
 124 /* Set the howto pointer for an MOXIE ELF reloc.  */
 125
 126 static void
 127 moxie_info_to_howto_rela (bfd *abfd ATTRIBUTE_UNUSED,
 128                           arelent *cache_ptr,
 129                           Elf_Internal_Rela *dst)
 130 {
 131   unsigned int r_type;
 132
 133   r_type = ELF32_R_TYPE (dst->r_info);
 134   if (r_type >= (unsigned int) R_MOXIE_max)
 135     {
 136       _bfd_error_handler (_("%B: invalid Moxie reloc number: %d"), abfd, r_type);
 137       r_type = 0;
 138     }
 139   cache_ptr->howto = & moxie_elf_howto_table [r_type];
 140 }
 141 \f
 142 /* Perform a single relocation.  By default we use the standard BFD
 143    routines, but a few relocs, we have to do them ourselves.  */
 144
 145 static bfd_reloc_status_type
 146 moxie_final_link_relocate (reloc_howto_type *howto,
 147                            bfd *input_bfd,
 148                            asection *input_section,
 149                            bfd_byte *contents,
 150                            Elf_Internal_Rela *rel,
 151                            bfd_vma relocation)
 152 {
 153   bfd_reloc_status_type r = bfd_reloc_ok;
 154
 155   switch (howto->type)
 156     {
 157     default:
 158       r = _bfd_final_link_relocate (howto, input_bfd, input_section,
 159                                     contents, rel->r_offset,
 160                                     relocation, rel->r_addend);
 161     }
 162
 163   return r;
 164 }
 165 \f
 166 /* Relocate an MOXIE ELF section.
 167
 168    The RELOCATE_SECTION function is called by the new ELF backend linker
 169    to handle the relocations for a section.
 170
 171    The relocs are always passed as Rela structures; if the section
 172    actually uses Rel structures, the r_addend field will always be
 173    zero.
 174
 175    This function is responsible for adjusting the section contents as
 176    necessary, and (if using Rela relocs and generating a relocatable
 177    output file) adjusting the reloc addend as necessary.
 178
 179    This function does not have to worry about setting the reloc
 180    address or the reloc symbol index.
 181
 182    LOCAL_SYMS is a pointer to the swapped in local symbols.
 183
 184    LOCAL_SECTIONS is an array giving the section in the input file
 185    corresponding to the st_shndx field of each local symbol.
 186
 187    The global hash table entry for the global symbols can be found
 188    via elf_sym_hashes (input_bfd).
 189
 190    When generating relocatable output, this function must handle
 191    STB_LOCAL/STT_SECTION symbols specially.  The output symbol is
 192    going to be the section symbol corresponding to the output
 193    section, which means that the addend must be adjusted
 194    accordingly.  */
 195
 196 static bfd_boolean
 197 moxie_elf_relocate_section (bfd *output_bfd,
 198                             struct bfd_link_info *info,
 199                             bfd *input_bfd,
 200                             asection *input_section,
 201                             bfd_byte *contents,
 202                             Elf_Internal_Rela *relocs,
 203                             Elf_Internal_Sym *local_syms,
 204                             asection **local_sections)
 205 {
 206   Elf_Internal_Shdr *symtab_hdr;
 207   struct elf_link_hash_entry **sym_hashes;
 208   Elf_Internal_Rela *rel;
 209   Elf_Internal_Rela *relend;
 210
 211   symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
 212   sym_hashes = elf_sym_hashes (input_bfd);
 213   relend     = relocs + input_section->reloc_count;
 214
 215   for (rel = relocs; rel < relend; rel ++)
 216     {
 217       reloc_howto_type *howto;
 218       unsigned long r_symndx;
 219       Elf_Internal_Sym *sym;
 220       asection *sec;
 221       struct elf_link_hash_entry *h;
 222       bfd_vma relocation;
 223       bfd_reloc_status_type r;
 224       const char *name;
 225       int r_type;
 226
 227       r_type = ELF32_R_TYPE (rel->r_info);
 228       r_symndx = ELF32_R_SYM (rel->r_info);
 229       howto  = moxie_elf_howto_table + r_type;
 230       h      = NULL;
 231       sym    = NULL;
 232       sec    = NULL;
 233
 234       if (r_symndx < symtab_hdr->sh_info)
 235         {
 236           sym = local_syms + r_symndx;
 237           sec = local_sections [r_symndx];
 238           relocation = _bfd_elf_rela_local_sym (output_bfd, sym, &sec, rel);
 239
 240           name = bfd_elf_string_from_elf_section
 241             (input_bfd, symtab_hdr->sh_link, sym->st_name);
 242           name = (name == NULL) ? bfd_section_name (input_bfd, sec) : name;
 243         }
 244       else
 245         {
 246           bfd_boolean unresolved_reloc, warned, ignored;
 247
 248           RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
 249                                    r_symndx, symtab_hdr, sym_hashes,
 250                                    h, sec, relocation,
 251                                    unresolved_reloc, warned, ignored);
 252
 253           name = h->root.root.string;
 254         }
 255
 256       if (sec != NULL && discarded_section (sec))
 257         RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section,
 258                                          rel, 1, relend, howto, 0, contents);
 259
 260       if (bfd_link_relocatable (info))
 261         continue;
 262
 263       r = moxie_final_link_relocate (howto, input_bfd, input_section,
 264                                      contents, rel, relocation);
 265
 266       if (r != bfd_reloc_ok)
 267         {
 268           const char * msg = NULL;
 269
 270           switch (r)
 271             {
 272             case bfd_reloc_overflow:
 273               (*info->callbacks->reloc_overflow)
 274                 (info, (h ? &h->root : NULL), name, howto->name,
 275                  (bfd_vma) 0, input_bfd, input_section, rel->r_offset);
 276               break;
 277
 278             case bfd_reloc_undefined:
 279               (*info->callbacks->undefined_symbol)
 280                 (info, name, input_bfd, input_section, rel->r_offset, TRUE);
 281               break;
 282
 283             case bfd_reloc_outofrange:
 284               msg = _("internal error: out of range error");
 285               break;
 286
 287             case bfd_reloc_notsupported:
 288               msg = _("internal error: unsupported relocation error");
 289               break;
 290
 291             case bfd_reloc_dangerous:
 292               msg = _("internal error: dangerous relocation");
 293               break;
 294
 295             default:
 296               msg = _("internal error: unknown error");
 297               break;
 298             }
 299
 300           if (msg)
 301             (*info->callbacks->warning) (info, msg, name, input_bfd,
 302                                          input_section, rel->r_offset);
 303         }
 304     }
 305
 306   return TRUE;
 307 }
 308 \f
 309 /* Return the section that should be marked against GC for a given
 310    relocation.  */
 311
 312 static asection *
 313 moxie_elf_gc_mark_hook (asection *sec,
 314                         struct bfd_link_info *info,
 315                         Elf_Internal_Rela *rel,
 316                         struct elf_link_hash_entry *h,
 317                         Elf_Internal_Sym *sym)
 318 {
 319   return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym);
 320 }
 321
 322 /* Look through the relocs for a section during the first phase.
 323    Since we don't do .gots or .plts, we just need to consider the
 324    virtual table relocs for gc.  */
 325
 326 static bfd_boolean
 327 moxie_elf_check_relocs (bfd *abfd,
 328                         struct bfd_link_info *info,
 329                         asection *sec,
 330                         const Elf_Internal_Rela *relocs)
 331 {
 332   Elf_Internal_Shdr *symtab_hdr;
 333   struct elf_link_hash_entry **sym_hashes;
 334   const Elf_Internal_Rela *rel;
 335   const Elf_Internal_Rela *rel_end;
 336
 337   if (bfd_link_relocatable (info))
 338     return TRUE;
 339
 340   symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
 341   sym_hashes = elf_sym_hashes (abfd);
 342
 343   rel_end = relocs + sec->reloc_count;
 344   for (rel = relocs; rel < rel_end; rel++)
 345     {
 346       struct elf_link_hash_entry *h;
 347       unsigned long r_symndx;
 348
 349       r_symndx = ELF32_R_SYM (rel->r_info);
 350       if (r_symndx < symtab_hdr->sh_info)
 351         h = NULL;
 352       else
 353         {
 354           h = sym_hashes[r_symndx - symtab_hdr->sh_info];
 355           while (h->root.type == bfd_link_hash_indirect
 356                  || h->root.type == bfd_link_hash_warning)
 357             h = (struct elf_link_hash_entry *) h->root.u.i.link;
 358
 359           /* PR15323, ref flags aren't set for references in the same
 360              object.  */
 361           h->root.non_ir_ref = 1;
 362         }
 363     }
 364
 365   return TRUE;
 366 }
 367 \f
 368 #define ELF_ARCH                bfd_arch_moxie
 369 #define ELF_MACHINE_CODE        EM_MOXIE
 370 #define ELF_MACHINE_ALT1        EM_MOXIE_OLD
 371 #define ELF_MAXPAGESIZE         0x1
 372
 373 #define TARGET_BIG_SYM          moxie_elf32_be_vec
 374 #define TARGET_BIG_NAME         "elf32-bigmoxie"
 375 #define TARGET_LITTLE_SYM       moxie_elf32_le_vec
 376 #define TARGET_LITTLE_NAME      "elf32-littlemoxie"
 377
 378 #define elf_info_to_howto_rel                   NULL
 379 #define elf_info_to_howto                       moxie_info_to_howto_rela
 380 #define elf_backend_relocate_section            moxie_elf_relocate_section
 381 #define elf_backend_gc_mark_hook                moxie_elf_gc_mark_hook
 382 #define elf_backend_check_relocs                moxie_elf_check_relocs
 383
 384 #define elf_backend_can_gc_sections             1
 385 #define elf_backend_rela_normal                 1
 386
 387 #define bfd_elf32_bfd_reloc_type_lookup         moxie_reloc_type_lookup
 388 #define bfd_elf32_bfd_reloc_name_lookup         moxie_reloc_name_lookup
 389
 390 #include "elf32-target.h"