bfd/elf32-moxie.c

   1 /* moxie-specific support for 32-bit ELF.
   2    Copyright (C) 2009-2014 Free Software Foundation, Inc.
   3
   4    Copied from elf32-fr30.c which is..
   5    Copyright (C) 1998-2014 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          2,                     /* size (0 = byte, 1 = short, 2 = long) */
  38          32,                    /* bitsize */
  39          FALSE,                 /* pc_relative */
  40          0,                     /* bitpos */
  41          complain_overflow_bitfield, /* 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   BFD_ASSERT (r_type < (unsigned int) R_MOXIE_max);
 135   cache_ptr->howto = & moxie_elf_howto_table [r_type];
 136 }
 137 \f
 138 /* Perform a single relocation.  By default we use the standard BFD
 139    routines, but a few relocs, we have to do them ourselves.  */
 140
 141 static bfd_reloc_status_type
 142 moxie_final_link_relocate (reloc_howto_type *howto,
 143                            bfd *input_bfd,
 144                            asection *input_section,
 145                            bfd_byte *contents,
 146                            Elf_Internal_Rela *rel,
 147                            bfd_vma relocation)
 148 {
 149   bfd_reloc_status_type r = bfd_reloc_ok;
 150
 151   switch (howto->type)
 152     {
 153     default:
 154       r = _bfd_final_link_relocate (howto, input_bfd, input_section,
 155                                     contents, rel->r_offset,
 156                                     relocation, rel->r_addend);
 157     }
 158
 159   return r;
 160 }
 161 \f
 162 /* Relocate an MOXIE ELF section.
 163
 164    The RELOCATE_SECTION function is called by the new ELF backend linker
 165    to handle the relocations for a section.
 166
 167    The relocs are always passed as Rela structures; if the section
 168    actually uses Rel structures, the r_addend field will always be
 169    zero.
 170
 171    This function is responsible for adjusting the section contents as
 172    necessary, and (if using Rela relocs and generating a relocatable
 173    output file) adjusting the reloc addend as necessary.
 174
 175    This function does not have to worry about setting the reloc
 176    address or the reloc symbol index.
 177
 178    LOCAL_SYMS is a pointer to the swapped in local symbols.
 179
 180    LOCAL_SECTIONS is an array giving the section in the input file
 181    corresponding to the st_shndx field of each local symbol.
 182
 183    The global hash table entry for the global symbols can be found
 184    via elf_sym_hashes (input_bfd).
 185
 186    When generating relocatable output, this function must handle
 187    STB_LOCAL/STT_SECTION symbols specially.  The output symbol is
 188    going to be the section symbol corresponding to the output
 189    section, which means that the addend must be adjusted
 190    accordingly.  */
 191
 192 static bfd_boolean
 193 moxie_elf_relocate_section (bfd *output_bfd,
 194                             struct bfd_link_info *info,
 195                             bfd *input_bfd,
 196                             asection *input_section,
 197                             bfd_byte *contents,
 198                             Elf_Internal_Rela *relocs,
 199                             Elf_Internal_Sym *local_syms,
 200                             asection **local_sections)
 201 {
 202   Elf_Internal_Shdr *symtab_hdr;
 203   struct elf_link_hash_entry **sym_hashes;
 204   Elf_Internal_Rela *rel;
 205   Elf_Internal_Rela *relend;
 206
 207   symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
 208   sym_hashes = elf_sym_hashes (input_bfd);
 209   relend     = relocs + input_section->reloc_count;
 210
 211   for (rel = relocs; rel < relend; rel ++)
 212     {
 213       reloc_howto_type *howto;
 214       unsigned long r_symndx;
 215       Elf_Internal_Sym *sym;
 216       asection *sec;
 217       struct elf_link_hash_entry *h;
 218       bfd_vma relocation;
 219       bfd_reloc_status_type r;
 220       const char *name;
 221       int r_type;
 222
 223       r_type = ELF32_R_TYPE (rel->r_info);
 224       r_symndx = ELF32_R_SYM (rel->r_info);
 225       howto  = moxie_elf_howto_table + r_type;
 226       h      = NULL;
 227       sym    = NULL;
 228       sec    = NULL;
 229
 230       if (r_symndx < symtab_hdr->sh_info)
 231         {
 232           sym = local_syms + r_symndx;
 233           sec = local_sections [r_symndx];
 234           relocation = _bfd_elf_rela_local_sym (output_bfd, sym, &sec, rel);
 235
 236           name = bfd_elf_string_from_elf_section
 237             (input_bfd, symtab_hdr->sh_link, sym->st_name);
 238           name = (name == NULL) ? bfd_section_name (input_bfd, sec) : name;
 239         }
 240       else
 241         {
 242           bfd_boolean unresolved_reloc, warned, ignored;
 243
 244           RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
 245                                    r_symndx, symtab_hdr, sym_hashes,
 246                                    h, sec, relocation,
 247                                    unresolved_reloc, warned, ignored);
 248
 249           name = h->root.root.string;
 250         }
 251
 252       if (sec != NULL && discarded_section (sec))
 253         RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section,
 254                                          rel, 1, relend, howto, 0, contents);
 255
 256       if (info->relocatable)
 257         continue;
 258
 259       r = moxie_final_link_relocate (howto, input_bfd, input_section,
 260                                      contents, rel, relocation);
 261
 262       if (r != bfd_reloc_ok)
 263         {
 264           const char * msg = NULL;
 265
 266           switch (r)
 267             {
 268             case bfd_reloc_overflow:
 269               r = info->callbacks->reloc_overflow
 270                 (info, (h ? &h->root : NULL), name, howto->name,
 271                  (bfd_vma) 0, input_bfd, input_section, rel->r_offset);
 272               break;
 273
 274             case bfd_reloc_undefined:
 275               r = info->callbacks->undefined_symbol
 276                 (info, name, input_bfd, input_section, rel->r_offset,
 277                  TRUE);
 278               break;
 279
 280             case bfd_reloc_outofrange:
 281               msg = _("internal error: out of range error");
 282               break;
 283
 284             case bfd_reloc_notsupported:
 285               msg = _("internal error: unsupported relocation error");
 286               break;
 287
 288             case bfd_reloc_dangerous:
 289               msg = _("internal error: dangerous relocation");
 290               break;
 291
 292             default:
 293               msg = _("internal error: unknown error");
 294               break;
 295             }
 296
 297           if (msg)
 298             r = info->callbacks->warning
 299               (info, msg, name, input_bfd, input_section, rel->r_offset);
 300
 301           if (! r)
 302             return FALSE;
 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 (info->relocatable)
 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_MAXPAGESIZE         0x1
 371
 372 #define TARGET_BIG_SYM          bfd_elf32_bigmoxie_vec
 373 #define TARGET_BIG_NAME         "elf32-bigmoxie"
 374 #define TARGET_LITTLE_SYM       bfd_elf32_littlemoxie_vec
 375 #define TARGET_LITTLE_NAME      "elf32-littlemoxie"
 376
 377 #define elf_info_to_howto_rel                   NULL
 378 #define elf_info_to_howto                       moxie_info_to_howto_rela
 379 #define elf_backend_relocate_section            moxie_elf_relocate_section
 380 #define elf_backend_gc_mark_hook                moxie_elf_gc_mark_hook
 381 #define elf_backend_check_relocs                moxie_elf_check_relocs
 382
 383 #define elf_backend_can_gc_sections             1
 384 #define elf_backend_rela_normal                 1
 385
 386 #define bfd_elf32_bfd_reloc_type_lookup         moxie_reloc_type_lookup
 387 #define bfd_elf32_bfd_reloc_name_lookup         moxie_reloc_name_lookup
 388
 389 #include "elf32-target.h"