bfd/elf32-arc.c

   1 /* ARC-specific support for 32-bit ELF
   2    Copyright (C) 1994, 1995, 1997, 1999 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 PARAMS ((bfd *));
  32 static void arc_elf_final_write_processing PARAMS ((bfd *, boolean));
  33
  34 /* Try to minimize the amount of space occupied by relocation tables
  35    on the ROM (not that the ROM won't be swamped by other ELF overhead).  */
  36 #define USE_REL
  37
  38 static reloc_howto_type elf_arc_howto_table[] =
  39 {
  40   /* This reloc does nothing.  */
  41   HOWTO (R_ARC_NONE,            /* type */
  42          0,                     /* rightshift */
  43          2,                     /* size (0 = byte, 1 = short, 2 = long) */
  44          32,                    /* bitsize */
  45          false,                 /* pc_relative */
  46          0,                     /* bitpos */
  47          complain_overflow_bitfield, /* complain_on_overflow */
  48          bfd_elf_generic_reloc, /* special_function */
  49          "R_ARC_NONE",          /* name */
  50          false,                 /* partial_inplace */
  51          0,                     /* src_mask */
  52          0,                     /* dst_mask */
  53          false),                /* pcrel_offset */
  54
  55   /* A standard 32 bit relocation.  */
  56   HOWTO (R_ARC_32,              /* type */
  57          0,                     /* rightshift */
  58          2,                     /* size (0 = byte, 1 = short, 2 = long) */
  59          32,                    /* bitsize */
  60          false,                 /* pc_relative */
  61          0,                     /* bitpos */
  62          complain_overflow_bitfield, /* complain_on_overflow */
  63          bfd_elf_generic_reloc, /* special_function */
  64          "R_ARC_32",            /* name */
  65          false,                 /* partial_inplace */
  66          0xffffffff,            /* src_mask */
  67          0xffffffff,            /* dst_mask */
  68          false),                /* pcrel_offset */
  69
  70   /* A 26 bit absolute branch, right shifted by 2.  */
  71   HOWTO (R_ARC_B26,             /* type */
  72          2,                     /* rightshift */
  73          2,                     /* size (0 = byte, 1 = short, 2 = long) */
  74          26,                    /* bitsize */
  75          false,                 /* pc_relative */
  76          0,                     /* bitpos */
  77          complain_overflow_bitfield, /* complain_on_overflow */
  78          bfd_elf_generic_reloc, /* special_function */
  79          "R_ARC_B26",           /* name */
  80          false,                 /* partial_inplace */
  81          0x00ffffff,            /* src_mask */
  82          0x00ffffff,            /* dst_mask */
  83          false),                /* pcrel_offset */
  84
  85   /* A relative 22 bit branch; bits 21-2 are stored in bits 26-7.  */
  86   HOWTO (R_ARC_B22_PCREL,       /* type */
  87          2,                     /* rightshift */
  88          2,                     /* size (0 = byte, 1 = short, 2 = long) */
  89          22,                    /* bitsize */
  90          true,                  /* pc_relative */
  91          7,                     /* bitpos */
  92          complain_overflow_signed, /* complain_on_overflow */
  93          bfd_elf_generic_reloc, /* special_function */
  94          "R_ARC_B22_PCREL",     /* name */
  95          false,                 /* partial_inplace */
  96          0x07ffff80,            /* src_mask */
  97          0x07ffff80,            /* dst_mask */
  98          true),                 /* pcrel_offset */
  99
 100 };
 101
 102 /* Map BFD reloc types to ARC ELF reloc types.  */
 103
 104 struct arc_reloc_map
 105 {
 106   bfd_reloc_code_real_type bfd_reloc_val;
 107   unsigned char elf_reloc_val;
 108 };
 109
 110 static const struct arc_reloc_map arc_reloc_map[] =
 111 {
 112   { BFD_RELOC_NONE, R_ARC_NONE, },
 113   { BFD_RELOC_32, R_ARC_32 },
 114   { BFD_RELOC_CTOR, R_ARC_32 },
 115   { BFD_RELOC_ARC_B26, R_ARC_B26 },
 116   { BFD_RELOC_ARC_B22_PCREL, R_ARC_B22_PCREL },
 117 };
 118
 119 static reloc_howto_type *
 120 bfd_elf32_bfd_reloc_type_lookup (abfd, code)
 121      bfd *abfd ATTRIBUTE_UNUSED;
 122      bfd_reloc_code_real_type code;
 123 {
 124   unsigned int i;
 125
 126   for (i = 0;
 127        i < sizeof (arc_reloc_map) / sizeof (struct arc_reloc_map);
 128        i++)
 129     {
 130       if (arc_reloc_map[i].bfd_reloc_val == code)
 131         return &elf_arc_howto_table[arc_reloc_map[i].elf_reloc_val];
 132     }
 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   int mach;
 159   unsigned long arch = elf_elfheader (abfd)->e_flags & EF_ARC_MACH;
 160
 161   switch (arch)
 162     {
 163     case E_ARC_MACH_BASE:
 164       mach = bfd_mach_arc_base;
 165       break;
 166     default:
 167       /* Unknown cpu type.  ??? What to do?  */
 168       return false;
 169     }
 170
 171   (void) bfd_default_set_arch_mach (abfd, bfd_arch_arc, mach);
 172   return true;
 173 }
 174
 175 /* The final processing done just before writing out an ARC ELF object file.
 176    This gets the ARC architecture right based on the machine number.  */
 177
 178 static void
 179 arc_elf_final_write_processing (abfd, linker)
 180      bfd *abfd;
 181      boolean linker ATTRIBUTE_UNUSED;
 182 {
 183   int mach;
 184   unsigned long val;
 185
 186   switch (mach = bfd_get_mach (abfd))
 187     {
 188     case bfd_mach_arc_base:
 189       val = E_ARC_MACH_BASE;
 190       break;
 191     default:
 192       return;
 193     }
 194
 195   elf_elfheader (abfd)->e_flags &=~ EF_ARC_MACH;
 196   elf_elfheader (abfd)->e_flags |= val;
 197 }
 198
 199 #define TARGET_LITTLE_SYM       bfd_elf32_littlearc_vec
 200 #define TARGET_LITTLE_NAME      "elf32-littlearc"
 201 #define TARGET_BIG_SYM          bfd_elf32_bigarc_vec
 202 #define TARGET_BIG_NAME         "elf32-bigarc"
 203 #define ELF_ARCH                bfd_arch_arc
 204 #define ELF_MACHINE_CODE        EM_CYGNUS_ARC
 205 #define ELF_MAXPAGESIZE         0x1000
 206
 207 #define elf_info_to_howto       0
 208 #define elf_info_to_howto_rel   arc_info_to_howto_rel
 209 #define elf_backend_object_p    arc_elf_object_p
 210 #define elf_backend_final_write_processing \
 211                                 arc_elf_final_write_processing
 212
 213 #include "elf32-target.h"