bfd/elf32-arc.c

   1 /* ARC-specific support for 32-bit ELF
   2    Copyright 1994, 1995, 1997, 1999, 2001 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  20
  21 #include "bfd.h"
  22 #include "sysdep.h"
  23 #include "libbfd.h"
  24 #include "elf-bfd.h"
  25 #include "elf/arc.h"
  26
  27 static reloc_howto_type *bfd_elf32_bfd_reloc_type_lookup
  28   PARAMS ((bfd *abfd, bfd_reloc_code_real_type code));
  29 static void arc_info_to_howto_rel
  30   PARAMS ((bfd *, arelent *, Elf32_Internal_Rel *));
  31 static boolean arc_elf_object_p
  32   PARAMS ((bfd *));
  33 static void arc_elf_final_write_processing
  34   PARAMS ((bfd *, boolean));
  35
  36 /* Try to minimize the amount of space occupied by relocation tables
  37    on the ROM (not that the ROM won't be swamped by other ELF overhead).  */
  38
  39 #define USE_REL
  40
  41 static reloc_howto_type elf_arc_howto_table[] =
  42 {
  43   /* This reloc does nothing.  */
  44   HOWTO (R_ARC_NONE,            /* type  */
  45          0,                     /* rightshift  */
  46          2,                     /* size (0 = byte, 1 = short, 2 = long)  */
  47          32,                    /* bitsize  */
  48          false,                 /* pc_relative  */
  49          0,                     /* bitpos  */
  50          complain_overflow_bitfield, /* complain_on_overflow  */
  51          bfd_elf_generic_reloc, /* special_function  */
  52          "R_ARC_NONE",          /* name  */
  53          false,                 /* partial_inplace  */
  54          0,                     /* src_mask  */
  55          0,                     /* dst_mask  */
  56          false),                /* pcrel_offset  */
  57
  58   /* A standard 32 bit relocation.  */
  59   HOWTO (R_ARC_32,              /* type  */
  60          0,                     /* rightshift  */
  61          2,                     /* size (0 = byte, 1 = short, 2 = long)  */
  62          32,                    /* bitsize  */
  63          false,                 /* pc_relative  */
  64          0,                     /* bitpos  */
  65          complain_overflow_bitfield, /* complain_on_overflow  */
  66          bfd_elf_generic_reloc, /* special_function  */
  67          "R_ARC_32",            /* name  */
  68          false,                 /* partial_inplace  */
  69          0xffffffff,            /* src_mask  */
  70          0xffffffff,            /* dst_mask  */
  71          false),                /* pcrel_offset  */
  72
  73   /* A 26 bit absolute branch, right shifted by 2.  */
  74   HOWTO (R_ARC_B26,             /* type  */
  75          2,                     /* rightshift  */
  76          2,                     /* size (0 = byte, 1 = short, 2 = long)  */
  77          26,                    /* bitsize  */
  78          false,                 /* pc_relative  */
  79          0,                     /* bitpos  */
  80          complain_overflow_bitfield, /* complain_on_overflow  */
  81          bfd_elf_generic_reloc, /* special_function  */
  82          "R_ARC_B26",           /* name  */
  83          false,                 /* partial_inplace  */
  84          0x00ffffff,            /* src_mask  */
  85          0x00ffffff,            /* dst_mask  */
  86          false),                /* pcrel_offset  */
  87
  88   /* A relative 22 bit branch; bits 21-2 are stored in bits 26-7.  */
  89   HOWTO (R_ARC_B22_PCREL,       /* type  */
  90          2,                     /* rightshift  */
  91          2,                     /* size (0 = byte, 1 = short, 2 = long)  */
  92          22,                    /* bitsize  */
  93          true,                  /* pc_relative  */
  94          7,                     /* bitpos  */
  95          complain_overflow_signed, /* complain_on_overflow  */
  96          bfd_elf_generic_reloc, /* special_function  */
  97          "R_ARC_B22_PCREL",     /* name  */
  98          true,                  /* partial_inplace  */
  99          0x07ffff80,            /* src_mask  */
 100          0x07ffff80,            /* dst_mask  */
 101          false),                /* pcrel_offset  */
 102
 103 };
 104
 105 /* Map BFD reloc types to ARC ELF reloc types.  */
 106
 107 struct arc_reloc_map
 108 {
 109   bfd_reloc_code_real_type bfd_reloc_val;
 110   unsigned char elf_reloc_val;
 111 };
 112
 113 static const struct arc_reloc_map arc_reloc_map[] =
 114 {
 115   { BFD_RELOC_NONE, R_ARC_NONE, },
 116   { BFD_RELOC_32, R_ARC_32 },
 117   { BFD_RELOC_CTOR, R_ARC_32 },
 118   { BFD_RELOC_ARC_B26, R_ARC_B26 },
 119   { BFD_RELOC_ARC_B22_PCREL, R_ARC_B22_PCREL },
 120 };
 121
 122 static reloc_howto_type *
 123 bfd_elf32_bfd_reloc_type_lookup (abfd, code)
 124      bfd *abfd ATTRIBUTE_UNUSED;
 125      bfd_reloc_code_real_type code;
 126 {
 127   unsigned int i;
 128
 129   for (i = 0; i < sizeof (arc_reloc_map) / sizeof (struct arc_reloc_map); i++)
 130     {
 131       if (arc_reloc_map[i].bfd_reloc_val == code)
 132         return &elf_arc_howto_table[arc_reloc_map[i].elf_reloc_val];
 133     }
 134   return NULL;
 135 }
 136
 137 /* Set the howto pointer for an ARC ELF reloc.  */
 138
 139 static void
 140 arc_info_to_howto_rel (abfd, cache_ptr, dst)
 141      bfd *abfd ATTRIBUTE_UNUSED;
 142      arelent *cache_ptr;
 143      Elf32_Internal_Rel *dst;
 144 {
 145   unsigned int r_type;
 146
 147   r_type = ELF32_R_TYPE (dst->r_info);
 148   BFD_ASSERT (r_type < (unsigned int) R_ARC_max);
 149   cache_ptr->howto = &elf_arc_howto_table[r_type];
 150 }
 151
 152 /* Set the right machine number for an ARC ELF file.  */
 153
 154 static boolean
 155 arc_elf_object_p (abfd)
 156      bfd *abfd;
 157 {
 158   unsigned int mach = bfd_mach_arc_6;
 159
 160   if (elf_elfheader(abfd)->e_machine == EM_ARC)
 161     {
 162       unsigned long arch = elf_elfheader (abfd)->e_flags & EF_ARC_MACH;
 163
 164       switch (arch)
 165         {
 166         case E_ARC_MACH_ARC5:
 167           mach = bfd_mach_arc_5;
 168           break;
 169         default:
 170         case E_ARC_MACH_ARC6:
 171           mach = bfd_mach_arc_6;
 172           break;
 173         case E_ARC_MACH_ARC7:
 174           mach = bfd_mach_arc_7;
 175           break;
 176         case E_ARC_MACH_ARC8:
 177           mach = bfd_mach_arc_8;
 178           break;
 179         }
 180     }
 181   return bfd_default_set_arch_mach (abfd, bfd_arch_arc, mach);
 182 }
 183
 184 /* The final processing done just before writing out an ARC ELF object file.
 185    This gets the ARC architecture right based on the machine number.  */
 186
 187 static void
 188 arc_elf_final_write_processing (abfd, linker)
 189      bfd *abfd;
 190      boolean linker ATTRIBUTE_UNUSED;
 191 {
 192   unsigned long val;
 193
 194   switch (bfd_get_mach (abfd))
 195     {
 196     case bfd_mach_arc_5:
 197       val = E_ARC_MACH_ARC5;
 198       break;
 199     default:
 200     case bfd_mach_arc_6:
 201       val = E_ARC_MACH_ARC6;
 202       break;
 203     case bfd_mach_arc_7:
 204       val = E_ARC_MACH_ARC7;
 205       break;
 206     case bfd_mach_arc_8:
 207       val = E_ARC_MACH_ARC8;
 208       break;
 209     }
 210   elf_elfheader (abfd)->e_flags &=~ EF_ARC_MACH;
 211   elf_elfheader (abfd)->e_flags |= val;
 212 }
 213
 214 #define TARGET_LITTLE_SYM bfd_elf32_littlearc_vec
 215 #define TARGET_LITTLE_NAME "elf32-littlearc"
 216 #define TARGET_BIG_SYM bfd_elf32_bigarc_vec
 217 #define TARGET_BIG_NAME "elf32-bigarc"
 218 #define ELF_ARCH bfd_arch_arc
 219 #define ELF_MACHINE_CODE EM_ARC
 220 #define ELF_MAXPAGESIZE 0x1000
 221
 222 #define elf_info_to_howto 0
 223 #define elf_info_to_howto_rel arc_info_to_howto_rel
 224 #define elf_backend_object_p arc_elf_object_p
 225 #define elf_backend_final_write_processing arc_elf_final_write_processing
 226
 227 #include "elf32-target.h"