Subversion Repositories openrisc_2011-10-31

/* ARC-specific support for 32-bit ELF

   Copyright 1994, 1995, 1997, 1999, 2001, 2002, 2005, 2007

   Free Software Foundation, Inc.

   Contributed by Doug Evans (dje@cygnus.com).

   This file is part of BFD, the Binary File Descriptor library.

   This program is free software; you can redistribute it and/or modify

   it under the terms of the GNU General Public License as published by

   the Free Software Foundation; either version 3 of the License, or

   (at your option) any later version.

   This program is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License

   along with this program; if not, write to the Free Software

   Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,

   MA 02110-1301, USA.  */

#include "sysdep.h"

#include "bfd.h"

#include "libbfd.h"

#include "elf-bfd.h"

#include "elf/arc.h"

#include "libiberty.h"

/* Try to minimize the amount of space occupied by relocation tables

   on the ROM (not that the ROM won't be swamped by other ELF overhead).  */

#define USE_REL 1

static bfd_reloc_status_type

arc_elf_b22_pcrel (bfd * abfd,

                   arelent * reloc_entry,

                   asymbol * symbol,

                   void * data,

                   asection * input_section,

                   bfd * output_bfd,

                   char ** error_message)

{

  /* If linking, back up the final symbol address by the address of the

     reloc.  This cannot be accomplished by setting the pcrel_offset

     field to TRUE, as bfd_install_relocation will detect this and refuse

     to install the offset in the first place, but bfd_perform_relocation

     will still insist on removing it.  */

  if (output_bfd == NULL)

    reloc_entry->addend -= reloc_entry->address;

  /* Fall through to the default elf reloc handler.  */

  return bfd_elf_generic_reloc (abfd, reloc_entry, symbol, data,

                                input_section, output_bfd, error_message);

}

static reloc_howto_type elf_arc_howto_table[] =

{

  /* This reloc does nothing.  */

  HOWTO (R_ARC_NONE,            /* Type.  */

         0,                      /* Rightshift.  */

         2,                     /* Size (0 = byte, 1 = short, 2 = long).  */

         32,                    /* Bitsize.  */

         FALSE,                 /* PC_relative.  */

         0,                      /* Bitpos.  */

         complain_overflow_bitfield, /* Complain_on_overflow.  */

         bfd_elf_generic_reloc, /* Special_function.  */

         "R_ARC_NONE",          /* Name.  */

         TRUE,                  /* Partial_inplace.  */

         0,                      /* Src_mask.  */

         0,                      /* Dst_mask.  */

         FALSE),                /* PCrel_offset.  */

  /* A standard 32 bit relocation.  */

  HOWTO (R_ARC_32,              /* Type.  */

         0,                      /* Rightshift.  */

         2,                     /* Size (0 = byte, 1 = short, 2 = long).  */

         32,                    /* Bitsize.  */

         FALSE,                 /* PC_relative.  */

         0,                      /* Bitpos.  */

         complain_overflow_bitfield, /* Complain_on_overflow.  */

         bfd_elf_generic_reloc, /* Special_function.  */

         "R_ARC_32",            /* Name.  */

         TRUE,                  /* Partial_inplace.  */

         0xffffffff,            /* Src_mask.  */

         0xffffffff,            /* Dst_mask.  */

         FALSE),                /* PCrel_offset.  */

  /* A 26 bit absolute branch, right shifted by 2.  */

  HOWTO (R_ARC_B26,             /* Type.  */

         2,                     /* Rightshift.  */

         2,                     /* Size (0 = byte, 1 = short, 2 = long).  */

         26,                    /* Bitsize.  */

         FALSE,                 /* PC_relative.  */

         0,                      /* Bitpos.  */

         complain_overflow_bitfield, /* Complain_on_overflow.  */

         bfd_elf_generic_reloc, /* Special_function.  */

         "R_ARC_B26",           /* Name.  */

         TRUE,                  /* Partial_inplace.  */

         0x00ffffff,            /* Src_mask.  */

         0x00ffffff,            /* Dst_mask.  */

         FALSE),                /* PCrel_offset.  */

  /* A relative 22 bit branch; bits 21-2 are stored in bits 26-7.  */

  HOWTO (R_ARC_B22_PCREL,       /* Type.  */

         2,                     /* Rightshift.  */

         2,                     /* Size (0 = byte, 1 = short, 2 = long).  */

         22,                    /* Bitsize.  */

         TRUE,                  /* PC_relative.  */

         7,                     /* Bitpos.  */

         complain_overflow_signed, /* Complain_on_overflow.  */

         arc_elf_b22_pcrel,     /* Special_function.  */

         "R_ARC_B22_PCREL",     /* Name.  */

         TRUE,                  /* Partial_inplace.  */

         0x07ffff80,            /* Src_mask.  */

         0x07ffff80,            /* Dst_mask.  */

         FALSE),                /* PCrel_offset.  */

};

/* Map BFD reloc types to ARC ELF reloc types.  */

struct arc_reloc_map

{

  bfd_reloc_code_real_type bfd_reloc_val;

  unsigned char elf_reloc_val;

};

static const struct arc_reloc_map arc_reloc_map[] =

{

  { BFD_RELOC_NONE, R_ARC_NONE, },

  { BFD_RELOC_32, R_ARC_32 },

  { BFD_RELOC_CTOR, R_ARC_32 },

  { BFD_RELOC_ARC_B26, R_ARC_B26 },

  { BFD_RELOC_ARC_B22_PCREL, R_ARC_B22_PCREL },

};

static reloc_howto_type *

bfd_elf32_bfd_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,

                                 bfd_reloc_code_real_type code)

{

  unsigned int i;

  for (i = ARRAY_SIZE (arc_reloc_map); i--;)

    if (arc_reloc_map[i].bfd_reloc_val == code)

      return elf_arc_howto_table + arc_reloc_map[i].elf_reloc_val;

  return NULL;

}

static reloc_howto_type *

bfd_elf32_bfd_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,

                                 const char *r_name)

{

  unsigned int i;

  for (i = 0;

       i < sizeof (elf_arc_howto_table) / sizeof (elf_arc_howto_table[0]);

       i++)

    if (elf_arc_howto_table[i].name != NULL

        && strcasecmp (elf_arc_howto_table[i].name, r_name) == 0)

      return &elf_arc_howto_table[i];

  return NULL;

}

/* Set the howto pointer for an ARC ELF reloc.  */

static void

arc_info_to_howto_rel (bfd *abfd ATTRIBUTE_UNUSED,

                       arelent *cache_ptr,

                       Elf_Internal_Rela *dst)

{

  unsigned int r_type;

  r_type = ELF32_R_TYPE (dst->r_info);

  BFD_ASSERT (r_type < (unsigned int) R_ARC_max);

  cache_ptr->howto = &elf_arc_howto_table[r_type];

}

/* Set the right machine number for an ARC ELF file.  */

static bfd_boolean

arc_elf_object_p (bfd *abfd)

{

  unsigned int mach = bfd_mach_arc_6;

  if (elf_elfheader(abfd)->e_machine == EM_ARC)

    {

      unsigned long arch = elf_elfheader (abfd)->e_flags & EF_ARC_MACH;

      switch (arch)

        {

        case E_ARC_MACH_ARC5:

          mach = bfd_mach_arc_5;

          break;

        default:

        case E_ARC_MACH_ARC6:

          mach = bfd_mach_arc_6;

          break;

        case E_ARC_MACH_ARC7:

          mach = bfd_mach_arc_7;

          break;

        case E_ARC_MACH_ARC8:

          mach = bfd_mach_arc_8;

          break;

        }

    }

  return bfd_default_set_arch_mach (abfd, bfd_arch_arc, mach);

}

/* The final processing done just before writing out an ARC ELF object file.

   This gets the ARC architecture right based on the machine number.  */

static void

arc_elf_final_write_processing (bfd *abfd,

                                bfd_boolean linker ATTRIBUTE_UNUSED)

{

  unsigned long val;

  switch (bfd_get_mach (abfd))

    {

    case bfd_mach_arc_5:

      val = E_ARC_MACH_ARC5;

      break;

    default:

    case bfd_mach_arc_6:

      val = E_ARC_MACH_ARC6;

      break;

    case bfd_mach_arc_7:

      val = E_ARC_MACH_ARC7;

      break;

    case bfd_mach_arc_8:

      val = E_ARC_MACH_ARC8;

      break;

    }

  elf_elfheader (abfd)->e_flags &=~ EF_ARC_MACH;

  elf_elfheader (abfd)->e_flags |= val;

}

#define TARGET_LITTLE_SYM   bfd_elf32_littlearc_vec

#define TARGET_LITTLE_NAME  "elf32-littlearc"

#define TARGET_BIG_SYM      bfd_elf32_bigarc_vec

#define TARGET_BIG_NAME     "elf32-bigarc"

#define ELF_ARCH            bfd_arch_arc

#define ELF_MACHINE_CODE    EM_ARC

#define ELF_MAXPAGESIZE     0x1000

#define elf_info_to_howto                   0

#define elf_info_to_howto_rel               arc_info_to_howto_rel

#define elf_backend_object_p                arc_elf_object_p

#define elf_backend_final_write_processing  arc_elf_final_write_processing

#include "elf32-target.h"