bfd/elf32-arc.c

   1 /* ARC-specific support for 32-bit ELF
   2    Copyright (C) 1994, 1995 Free Software Foundation, Inc.
   3    Contributed by Doug Evans (dje@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 2 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., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  20
  21 #include "bfd.h"
  22 #include "sysdep.h"
  23 #include "libbfd.h"
  24 #include "libelf.h"
  25 #include "elf/arc.h"
  26
  27 static bfd_reloc_status_type arc_elf_unsupported_reloc
  28   PARAMS ((bfd *, arelent *, asymbol *, PTR, asection *, bfd *, char **));
  29 static reloc_howto_type *bfd_elf32_bfd_reloc_type_lookup
  30   PARAMS ((bfd *abfd, bfd_reloc_code_real_type code));
  31 static void arc_info_to_howto_rel
  32   PARAMS ((bfd *, arelent *, Elf32_Internal_Rel *));
  33 static boolean arc_elf_object_p PARAMS ((bfd *));
  34 static void arc_elf_final_write_processing PARAMS ((bfd *, boolean));
  35
  36 /* Try to minimize the amount of space occupied by relocation tables
  37    on the ROM.  */
  38 #define USE_REL
  39
  40 enum reloc_type
  41 {
  42   R_ARC_NONE = 0,
  43   R_ARC_ADDR32,
  44   R_ARC_B22_PCREL,
  45   R_ARC_max
  46 };
  47
  48 static reloc_howto_type elf_arc_howto_table[] =
  49 {
  50   /* This reloc does nothing.  */
  51   HOWTO (R_ARC_NONE,            /* type */
  52          0,                     /* rightshift */
  53          2,                     /* size (0 = byte, 1 = short, 2 = long) */
  54          32,                    /* bitsize */
  55          false,                 /* pc_relative */
  56          0,                     /* bitpos */
  57          complain_overflow_bitfield, /* complain_on_overflow */
  58          bfd_elf_generic_reloc, /* special_function */
  59          "R_ARC_NONE",          /* name */
  60          false,                 /* partial_inplace */
  61          0,                     /* src_mask */
  62          0,                     /* dst_mask */
  63          false),                /* pcrel_offset */
  64
  65   /* A standard 32 bit relocation.  */
  66   HOWTO (R_ARC_ADDR32,          /* type */
  67          0,                     /* rightshift */
  68          2,                     /* size (0 = byte, 1 = short, 2 = long) */
  69          32,                    /* bitsize */
  70          false,                 /* pc_relative */
  71          0,                     /* bitpos */
  72          complain_overflow_bitfield, /* complain_on_overflow */
  73          bfd_elf_generic_reloc, /* special_function */
  74          "R_ARC_ADDR32",        /* name */
  75          false,                 /* partial_inplace */
  76          0,                     /* src_mask */
  77          0xffffffff,            /* dst_mask */
  78          false),                /* pcrel_offset */
  79
  80   /* A relative 22 bit branch; the lower two bits must be zero.  */
  81   HOWTO (R_ARC_B22_PCREL,       /* type */
  82          2,                     /* rightshift */
  83          2,                     /* size (0 = byte, 1 = short, 2 = long) */
  84          22,                    /* bitsize */
  85          true,                  /* pc_relative */
  86          7,                     /* bitpos */
  87          complain_overflow_signed, /* complain_on_overflow */
  88          bfd_elf_generic_reloc, /* special_function */
  89          "R_ARC_B22_PCREL",     /* name */
  90          false,                 /* partial_inplace */
  91          0,                     /* src_mask */
  92          0x07ffff80,            /* dst_mask */
  93          true),                 /* pcrel_offset */
  94
  95 };
  96
  97 /* Don't pretend we can deal with unsupported relocs.  */
  98
  99 static bfd_reloc_status_type
 100 arc_elf_unsupported_reloc (abfd, reloc_entry, symbol, data, input_section,
 101                            output_bfd, error_message)
 102      bfd *abfd;
 103      arelent *reloc_entry;
 104      asymbol *symbol;
 105      PTR data;
 106      asection *input_section;
 107      bfd *output_bfd;
 108      char **error_message;
 109 {
 110   abort ();
 111 }
 112
 113 /* Map BFD reloc types to ARC ELF reloc types.  */
 114
 115 struct arc_reloc_map
 116 {
 117   unsigned char bfd_reloc_val;
 118   unsigned char elf_reloc_val;
 119 };
 120
 121 static const struct arc_reloc_map arc_reloc_map[] =
 122 {
 123   { BFD_RELOC_NONE, R_ARC_NONE, },
 124   { BFD_RELOC_32, R_ARC_ADDR32 },
 125   { BFD_RELOC_CTOR, R_ARC_ADDR32 },
 126   { BFD_RELOC_ARC_B22_PCREL, R_ARC_B22_PCREL },
 127 };
 128
 129 static reloc_howto_type *
 130 bfd_elf32_bfd_reloc_type_lookup (abfd, code)
 131      bfd *abfd;
 132      bfd_reloc_code_real_type code;
 133 {
 134   int i;
 135
 136   for (i = 0;
 137        i < sizeof (arc_reloc_map) / sizeof (struct arc_reloc_map);
 138        i++)
 139     {
 140       if (arc_reloc_map[i].bfd_reloc_val == code)
 141         return &elf_arc_howto_table[arc_reloc_map[i].elf_reloc_val];
 142     }
 143
 144   return NULL;
 145 }
 146
 147 /* Set the howto pointer for an ARC ELF reloc.  */
 148
 149 static void
 150 arc_info_to_howto_rel (abfd, cache_ptr, dst)
 151      bfd *abfd;
 152      arelent *cache_ptr;
 153      Elf32_Internal_Rel *dst;
 154 {
 155   unsigned int r_type;
 156
 157   r_type = ELF32_R_TYPE (dst->r_info);
 158   BFD_ASSERT (r_type < (unsigned int) R_ARC_max);
 159   cache_ptr->howto = &elf_arc_howto_table[r_type];
 160 }
 161
 162 /* Set the right machine number for an ARC ELF file.  */
 163
 164 static boolean
 165 arc_elf_object_p (abfd)
 166      bfd *abfd;
 167 {
 168   int mach;
 169   unsigned long arch = elf_elfheader (abfd)->e_flags & EF_ARC_CPU;
 170
 171   switch (arch)
 172     {
 173     case E_ARC_CPU_BASE:
 174       mach = bfd_mach_arc_base;
 175       break;
 176     case E_ARC_CPU_HOST:
 177       mach = bfd_mach_arc_host;
 178       break;
 179     case E_ARC_CPU_GRAPHICS:
 180       mach = bfd_mach_arc_graphics;
 181       break;
 182     case E_ARC_CPU_AUDIO:
 183       mach = bfd_mach_arc_audio;
 184       break;
 185     default:
 186       /* Unknown cpu type.  ??? What to do?  */
 187       return false;
 188     }
 189
 190   (void) bfd_default_set_arch_mach (abfd, bfd_arch_arc, mach);
 191   return true;
 192 }
 193
 194 /* The final processing done just before writing out an ARC ELF object file.
 195    This gets the ARC architecture right based on the machine number.  */
 196
 197 static void
 198 arc_elf_final_write_processing (abfd, linker)
 199      bfd *abfd;
 200      boolean linker;
 201 {
 202   int mach;
 203   unsigned long val;
 204
 205   switch (mach = bfd_get_mach (abfd))
 206     {
 207     case bfd_mach_arc_base:
 208       val = E_ARC_CPU_BASE;
 209       break;
 210     case bfd_mach_arc_host:
 211       val = E_ARC_CPU_HOST;
 212       break;
 213     case bfd_mach_arc_graphics:
 214       val = E_ARC_CPU_GRAPHICS;
 215       break;
 216     case bfd_mach_arc_audio:
 217       val = E_ARC_CPU_AUDIO;
 218       break;
 219     default:
 220       return;
 221     }
 222
 223   elf_elfheader (abfd)->e_flags &=~ EF_ARC_CPU;
 224   elf_elfheader (abfd)->e_flags |= val;
 225 }
 226
 227 #define TARGET_LITTLE_SYM       bfd_elf32_arc_vec
 228 #define TARGET_LITTLE_NAME      "elf32-arc"
 229 #define ELF_ARCH                bfd_arch_arc
 230 #define ELF_MACHINE_CODE        EM_CYGNUS_ARC
 231 #define ELF_MAXPAGESIZE         0x1000
 232
 233 #define elf_info_to_howto       0
 234 #define elf_info_to_howto_rel   arc_info_to_howto_rel
 235 #define elf_backend_object_p    arc_elf_object_p
 236 #define elf_backend_final_write_processing \
 237                                 arc_elf_final_write_processing
 238
 239 #include "elf32-target.h"