binutils-gdb/bfd/elf32-xstormy16.c

/* Xstormy16-specific support for 32-bit ELF.
   Copyright 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2010, 2011, 2012
   Free Software Foundation, Inc.

   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/xstormy16.h"
#include "libiberty.h"

/* Handle the R_XSTORMY16_24 reloc, which has an odd bit arrangement.  */

static bfd_reloc_status_type
xstormy16_elf_24_reloc (bfd *abfd,
			arelent *reloc_entry,
			asymbol *symbol,
			void * data,
			asection *input_section,
			bfd *output_bfd,
			char **error_message ATTRIBUTE_UNUSED)
{
  bfd_vma relocation, x;

  if (output_bfd != NULL)
    {
      reloc_entry->address += input_section->output_offset;
      return bfd_reloc_ok;
    }

  if (reloc_entry->address > bfd_get_section_limit (abfd, input_section))
    return bfd_reloc_outofrange;

  if (bfd_is_com_section (symbol->section))
    relocation = 0;
  else
    relocation = symbol->value;

  relocation += symbol->section->output_section->vma;
  relocation += symbol->section->output_offset;
  relocation += reloc_entry->addend;

  x = bfd_get_32 (abfd, (bfd_byte *) data + reloc_entry->address);
  x &= 0x0000ff00;
  x |= relocation & 0xff;
  x |= (relocation << 8) & 0xffff0000;
  bfd_put_32 (abfd, x, (bfd_byte *) data + reloc_entry->address);

  if (relocation & ~ (bfd_vma) 0xffffff)
    return bfd_reloc_overflow;

  return bfd_reloc_ok;
}

static reloc_howto_type xstormy16_elf_howto_table [] =
{
  /* This reloc does nothing.  */
  HOWTO (R_XSTORMY16_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_XSTORMY16_NONE",	/* name */
	 FALSE,			/* partial_inplace */
	 0,			/* src_mask */
	 0,			/* dst_mask */
	 FALSE),		/* pcrel_offset */

  /* A 32 bit absolute relocation.  */
  HOWTO (R_XSTORMY16_32,	/* type */
	 0,			/* rightshift */
	 2,			/* size (0 = byte, 1 = short, 2 = long) */
	 32,			/* bitsize */
	 FALSE,			/* pc_relative */
	 0,			/* bitpos */
	 complain_overflow_dont, /* complain_on_overflow */
	 bfd_elf_generic_reloc,	/* special_function */
	 "R_XSTORMY16_32",	/* name */
	 FALSE,			/* partial_inplace */
	 0,			/* src_mask */
	 0xffffffff,		/* dst_mask */
	 FALSE),		/* pcrel_offset */

  /* A 16 bit absolute relocation.  */
  HOWTO (R_XSTORMY16_16,	/* type */
	 0,			/* rightshift */
	 1,			/* size (0 = byte, 1 = short, 2 = long) */
	 16,			/* bitsize */
	 FALSE,			/* pc_relative */
	 0,			/* bitpos */
	 complain_overflow_bitfield, /* complain_on_overflow */
	 bfd_elf_generic_reloc,	/* special_function */
	 "R_XSTORMY16_16",	/* name */
	 FALSE,			/* partial_inplace */
	 0,			/* src_mask */
	 0xffff,		/* dst_mask */
	 FALSE),		/* pcrel_offset */

  /* An 8 bit absolute relocation.  */
  HOWTO (R_XSTORMY16_8,		/* type */
	 0,			/* rightshift */
	 0,			/* size (0 = byte, 1 = short, 2 = long) */
	 8,			/* bitsize */
	 FALSE,			/* pc_relative */
	 0,			/* bitpos */
	 complain_overflow_unsigned, /* complain_on_overflow */
	 bfd_elf_generic_reloc,	/* special_function */
	 "R_XSTORMY16_8",	/* name */
	 FALSE,			/* partial_inplace */
	 0,			/* src_mask */
	 0xff,			/* dst_mask */
	 FALSE),		/* pcrel_offset */

  /* A 32 bit pc-relative relocation.  */
  HOWTO (R_XSTORMY16_PC32,	/* type */
	 0,			/* rightshift */
	 2,			/* size (0 = byte, 1 = short, 2 = long) */
	 32,			/* bitsize */
	 TRUE,			/* pc_relative */
	 0,			/* bitpos */
	 complain_overflow_dont, /* complain_on_overflow */
	 bfd_elf_generic_reloc,	/* special_function */
	 "R_XSTORMY16_PC32",	/* name */
	 FALSE,			/* partial_inplace */
	 0,			/* src_mask */
	 0xffffffff,		/* dst_mask */
	 TRUE),			/* pcrel_offset */

  /* A 16 bit pc-relative relocation.  */
  HOWTO (R_XSTORMY16_PC16,	/* type */
	 0,			/* rightshift */
	 1,			/* size (0 = byte, 1 = short, 2 = long) */
	 16,			/* bitsize */
	 TRUE,			/* pc_relative */
	 0,			/* bitpos */
	 complain_overflow_signed, /* complain_on_overflow */
	 bfd_elf_generic_reloc,	/* special_function */
	 "R_XSTORMY16_PC16",	/* name */
	 FALSE,			/* partial_inplace */
	 0,			/* src_mask */
	 0xffffffff,		/* dst_mask */
	 TRUE),			/* pcrel_offset */

  /* An 8 bit pc-relative relocation.  */
  HOWTO (R_XSTORMY16_PC8,	/* type */
	 0,			/* rightshift */
	 0,			/* size (0 = byte, 1 = short, 2 = long) */
	 8,			/* bitsize */
	 TRUE,			/* pc_relative */
	 0,			/* bitpos */
	 complain_overflow_signed, /* complain_on_overflow */
	 bfd_elf_generic_reloc,	/* special_function */
	 "R_XSTORMY16_PC8",	/* name */
	 FALSE,			/* partial_inplace */
	 0,			/* src_mask */
	 0xffffffff,		/* dst_mask */
	 TRUE),			/* pcrel_offset */

  /* A 12-bit pc-relative relocation suitable for the branch instructions.  */
  HOWTO (R_XSTORMY16_REL_12,	/* type */
	 1,			/* rightshift */
	 1,			/* size (0 = byte, 1 = short, 2 = long) */
	 11,			/* bitsize */
	 TRUE,			/* pc_relative */
	 1,			/* bitpos */
	 complain_overflow_signed, /* complain_on_overflow */
	 bfd_elf_generic_reloc,	/* special_function */
	 "R_XSTORMY16_REL_12",	/* name */
	 FALSE,			/* partial_inplace */
	 0,			/* src_mask */
	 0x0ffe,		/* dst_mask */
	 TRUE),			/* pcrel_offset */

  /* A 24-bit absolute relocation suitable for the jump instructions.  */
  HOWTO (R_XSTORMY16_24,	/* type */
	 0,			/* rightshift */
	 2,			/* size (0 = byte, 1 = short, 2 = long) */
	 24,			/* bitsize */
	 FALSE,			/* pc_relative */
	 0,			/* bitpos */
	 complain_overflow_unsigned, /* complain_on_overflow */
	 xstormy16_elf_24_reloc,	/* special_function */
	 "R_XSTORMY16_24",	/* name */
	 TRUE,			/* partial_inplace */
	 0,			/* src_mask */
	 0xffff00ff,		/* dst_mask */
	 TRUE),			/* pcrel_offset */

  /* A 16 bit absolute relocation to a function pointer.  */
  HOWTO (R_XSTORMY16_FPTR16,	/* type */
	 0,			/* rightshift */
	 1,			/* size (0 = byte, 1 = short, 2 = long) */
	 16,			/* bitsize */
	 FALSE,			/* pc_relative */
	 0,			/* bitpos */
	 complain_overflow_bitfield, /* complain_on_overflow */
	 bfd_elf_generic_reloc,	/* special_function */
	 "R_XSTORMY16_FPTR16",	/* name */
	 FALSE,			/* partial_inplace */
	 0,			/* src_mask */
	 0xffffffff,		/* dst_mask */
	 FALSE),		/* pcrel_offset */

  /* Low order 16 bit value of a high memory address.  */
  HOWTO (R_XSTORMY16_LO16,	/* type */
	 0,			/* rightshift */
	 1,			/* size (0 = byte, 1 = short, 2 = long) */
	 16,			/* bitsize */
	 FALSE,			/* pc_relative */
	 0,			/* bitpos */
	 complain_overflow_dont, /* complain_on_overflow */
	 bfd_elf_generic_reloc,	/* special_function */
	 "R_XSTORMY16_LO16",	/* name */
	 FALSE,			/* partial_inplace */
	 0,			/* src_mask */
	 0xffff,		/* dst_mask */
	 FALSE),		/* pcrel_offset */

  /* High order 16 bit value of a high memory address.  */
  HOWTO (R_XSTORMY16_HI16,	/* type */
	 16,			/* rightshift */
	 1,			/* size (0 = byte, 1 = short, 2 = long) */
	 16,			/* bitsize */
	 FALSE,			/* pc_relative */
	 0,			/* bitpos */
	 complain_overflow_dont, /* complain_on_overflow */
	 bfd_elf_generic_reloc,	/* special_function */
	 "R_XSTORMY16_HI16",	/* name */
	 FALSE,			/* partial_inplace */
	 0,			/* src_mask */
	 0xffff,		/* dst_mask */
	 FALSE),		/* pcrel_offset */

  /* A 12 bit absolute relocation.  */
  HOWTO (R_XSTORMY16_12,	/* type */
	 0,			/* rightshift */
	 1,			/* size (0 = byte, 1 = short, 2 = long) */
	 12,			/* bitsize */
	 FALSE,			/* pc_relative */
	 0,			/* bitpos */
	 complain_overflow_signed, /* complain_on_overflow */
	 bfd_elf_generic_reloc,	/* special_function */
	 "R_XSTORMY16_12",	/* name */
	 FALSE,			/* partial_inplace */
	 0x0000,		/* src_mask */
	 0x0fff,		/* dst_mask */
	 FALSE),		/* pcrel_offset */
};

static reloc_howto_type xstormy16_elf_howto_table2 [] =
{
  /* GNU extension to record C++ vtable hierarchy */
  HOWTO (R_XSTORMY16_GNU_VTINHERIT, /* type */
         0,                     /* rightshift */
         2,                     /* size (0 = byte, 1 = short, 2 = long) */
         0,                     /* bitsize */
         FALSE,                 /* pc_relative */
         0,                     /* bitpos */
         complain_overflow_dont, /* complain_on_overflow */
         NULL,                  /* special_function */
         "R_XSTORMY16_GNU_VTINHERIT", /* name */
         FALSE,                 /* partial_inplace */
         0,                     /* src_mask */
         0,                     /* dst_mask */
         FALSE),                /* pcrel_offset */

  /* GNU extension to record C++ vtable member usage */
  HOWTO (R_XSTORMY16_GNU_VTENTRY,     /* type */
         0,                     /* rightshift */
         2,                     /* size (0 = byte, 1 = short, 2 = long) */
         0,                     /* bitsize */
         FALSE,                 /* pc_relative */
         0,                     /* bitpos */
         complain_overflow_dont, /* complain_on_overflow */
         _bfd_elf_rel_vtable_reloc_fn,  /* special_function */
         "R_XSTORMY16_GNU_VTENTRY",   /* name */
         FALSE,                 /* partial_inplace */
         0,                     /* src_mask */
         0,                     /* dst_mask */
         FALSE),                /* pcrel_offset */

};

/* Map BFD reloc types to XSTORMY16 ELF reloc types.  */

typedef struct xstormy16_reloc_map
{
  bfd_reloc_code_real_type  bfd_reloc_val;
  unsigned int              xstormy16_reloc_val;
  reloc_howto_type *        table;
} reloc_map;

static const reloc_map xstormy16_reloc_map [] =
{
  { BFD_RELOC_NONE,                 R_XSTORMY16_NONE,          xstormy16_elf_howto_table },
  { BFD_RELOC_32,                   R_XSTORMY16_32,            xstormy16_elf_howto_table },
  { BFD_RELOC_16,                   R_XSTORMY16_16,            xstormy16_elf_howto_table },
  { BFD_RELOC_8,                    R_XSTORMY16_8,             xstormy16_elf_howto_table },
  { BFD_RELOC_32_PCREL,             R_XSTORMY16_PC32,          xstormy16_elf_howto_table },
  { BFD_RELOC_16_PCREL,             R_XSTORMY16_PC16,          xstormy16_elf_howto_table },
  { BFD_RELOC_8_PCREL,              R_XSTORMY16_PC8,           xstormy16_elf_howto_table },
  { BFD_RELOC_XSTORMY16_REL_12,     R_XSTORMY16_REL_12,        xstormy16_elf_howto_table },
  { BFD_RELOC_XSTORMY16_24,	    R_XSTORMY16_24,            xstormy16_elf_howto_table },
  { BFD_RELOC_XSTORMY16_FPTR16,	    R_XSTORMY16_FPTR16,        xstormy16_elf_howto_table },
  { BFD_RELOC_LO16,                 R_XSTORMY16_LO16,          xstormy16_elf_howto_table },
  { BFD_RELOC_HI16,                 R_XSTORMY16_HI16,          xstormy16_elf_howto_table },
  { BFD_RELOC_XSTORMY16_12,         R_XSTORMY16_12,            xstormy16_elf_howto_table },
  { BFD_RELOC_VTABLE_INHERIT,       R_XSTORMY16_GNU_VTINHERIT, xstormy16_elf_howto_table2 },
  { BFD_RELOC_VTABLE_ENTRY,         R_XSTORMY16_GNU_VTENTRY,   xstormy16_elf_howto_table2 },
};

static reloc_howto_type *
xstormy16_reloc_type_lookup (bfd * abfd ATTRIBUTE_UNUSED,
			     bfd_reloc_code_real_type code)
{
  unsigned int i;

  for (i = ARRAY_SIZE (xstormy16_reloc_map); --i;)
    {
      const reloc_map * entry;

      entry = xstormy16_reloc_map + i;

      if (entry->bfd_reloc_val == code)
	return entry->table + (entry->xstormy16_reloc_val
			       - entry->table[0].type);
    }

  return NULL;
}

static reloc_howto_type *
xstormy16_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
			     const char *r_name)
{
  unsigned int i;

  for (i = 0;
       i < (sizeof (xstormy16_elf_howto_table)
	    / sizeof (xstormy16_elf_howto_table[0]));
       i++)
    if (xstormy16_elf_howto_table[i].name != NULL
	&& strcasecmp (xstormy16_elf_howto_table[i].name, r_name) == 0)
      return &xstormy16_elf_howto_table[i];

  for (i = 0;
       i < (sizeof (xstormy16_elf_howto_table2)
	    / sizeof (xstormy16_elf_howto_table2[0]));
       i++)
    if (xstormy16_elf_howto_table2[i].name != NULL
	&& strcasecmp (xstormy16_elf_howto_table2[i].name, r_name) == 0)
      return &xstormy16_elf_howto_table2[i];

  return NULL;
}

/* Set the howto pointer for an XSTORMY16 ELF reloc.  */

static void
xstormy16_info_to_howto_rela (bfd * abfd ATTRIBUTE_UNUSED,
			      arelent * cache_ptr,
			      Elf_Internal_Rela * dst)
{
  unsigned int r_type = ELF32_R_TYPE (dst->r_info);

  if (r_type <= (unsigned int) R_XSTORMY16_12)
    cache_ptr->howto = &xstormy16_elf_howto_table [r_type];
  else if (r_type - R_XSTORMY16_GNU_VTINHERIT
	   <= (unsigned int) R_XSTORMY16_GNU_VTENTRY)
    cache_ptr->howto
      = &xstormy16_elf_howto_table2 [r_type - R_XSTORMY16_GNU_VTINHERIT];
  else
    abort ();
}

/* We support 16-bit pointers to code above 64k by generating a thunk
   below 64k containing a JMPF instruction to the final address.  We
   cannot, unfortunately, minimize the number of thunks unless the
   -relax switch is given, as otherwise we have no idea where the
   sections will fall in the address space.  */

static bfd_boolean
xstormy16_elf_check_relocs (bfd *abfd,
			    struct bfd_link_info *info,
			    asection *sec,
			    const Elf_Internal_Rela *relocs)
{
  const Elf_Internal_Rela *rel, *relend;
  struct elf_link_hash_entry **sym_hashes;
  Elf_Internal_Shdr *symtab_hdr;
  bfd_vma *local_plt_offsets;
  asection *splt;
  bfd *dynobj;

  if (info->relocatable)
    return TRUE;

  symtab_hdr = &elf_tdata(abfd)->symtab_hdr;
  sym_hashes = elf_sym_hashes (abfd);
  local_plt_offsets = elf_local_got_offsets (abfd);
  splt = NULL;
  dynobj = elf_hash_table(info)->dynobj;

  relend = relocs + sec->reloc_count;
  for (rel = relocs; rel < relend; ++rel)
    {
      unsigned long r_symndx;
      struct elf_link_hash_entry *h;
      bfd_vma *offset;

      r_symndx = ELF32_R_SYM (rel->r_info);
      if (r_symndx < symtab_hdr->sh_info)
	h = NULL;
      else
	{
	  h = sym_hashes[r_symndx - symtab_hdr->sh_info];
	  while (h->root.type == bfd_link_hash_indirect
		 || h->root.type == bfd_link_hash_warning)
	    h = (struct elf_link_hash_entry *) h->root.u.i.link;
	}

      switch (ELF32_R_TYPE (rel->r_info))
        {
	  /* This relocation describes a 16-bit pointer to a function.
	     We may need to allocate a thunk in low memory; reserve memory
	     for it now.  */
	case R_XSTORMY16_FPTR16:
	  if (rel->r_addend != 0)
	    {
	      (*info->callbacks->warning)
		(info, _("non-zero addend in @fptr reloc"), 0,
		 abfd, 0, 0);
	    }

	  if (dynobj == NULL)
	    elf_hash_table (info)->dynobj = dynobj = abfd;
	  if (splt == NULL)
	    {
	      splt = bfd_get_linker_section (dynobj, ".plt");
	      if (splt == NULL)
		{
		  flagword flags = (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS
				    | SEC_IN_MEMORY | SEC_LINKER_CREATED
				    | SEC_READONLY | SEC_CODE);

		  splt = bfd_make_section_anyway_with_flags (dynobj, ".plt",
							     flags);
		  if (splt == NULL
		      || ! bfd_set_section_alignment (dynobj, splt, 1))
		    return FALSE;
		}
	    }

	  if (h != NULL)
	    offset = &h->plt.offset;
	  else
	    {
	      if (local_plt_offsets == NULL)
		{
		  size_t size;
		  unsigned int i;

		  size = symtab_hdr->sh_info * sizeof (bfd_vma);
		  local_plt_offsets = bfd_alloc (abfd, size);
		  if (local_plt_offsets == NULL)
		    return FALSE;
		  elf_local_got_offsets (abfd) = local_plt_offsets;

		  for (i = 0; i < symtab_hdr->sh_info; i++)
		    local_plt_offsets[i] = (bfd_vma) -1;
		}
	      offset = &local_plt_offsets[r_symndx];
	    }

	  if (*offset == (bfd_vma) -1)
	    {
	      *offset = splt->size;
	      splt->size += 4;
	    }
	  break;

	  /* This relocation describes the C++ object vtable hierarchy.
	     Reconstruct it for later use during GC.  */
        case R_XSTORMY16_GNU_VTINHERIT:
          if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
            return FALSE;
          break;

	  /* This relocation describes which C++ vtable entries are actually
	     used.  Record for later use during GC.  */
        case R_XSTORMY16_GNU_VTENTRY:
          BFD_ASSERT (h != NULL);
          if (h != NULL
              && !bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_addend))
            return FALSE;
          break;
	}
    }

  return TRUE;
}

/* A subroutine of xstormy16_elf_relax_section.  If the global symbol H
   is within the low 64k, remove any entry for it in the plt.  */

struct relax_plt_data
{
  asection *splt;
  bfd_boolean *again;
};

static bfd_boolean
xstormy16_relax_plt_check (struct elf_link_hash_entry *h, void * xdata)
{
  struct relax_plt_data *data = (struct relax_plt_data *) xdata;

  if (h->plt.offset != (bfd_vma) -1)
    {
      bfd_vma address;

      if (h->root.type == bfd_link_hash_undefined
	  || h->root.type == bfd_link_hash_undefweak)
	address = 0;
      else
	address = (h->root.u.def.section->output_section->vma
		   + h->root.u.def.section->output_offset
		   + h->root.u.def.value);

      if (address <= 0xffff)
	{
	  h->plt.offset = -1;
	  data->splt->size -= 4;
	  *data->again = TRUE;
	}
    }

  return TRUE;
}

/* A subroutine of xstormy16_elf_relax_section.  If the global symbol H
   previously had a plt entry, give it a new entry offset.  */

static bfd_boolean
xstormy16_relax_plt_realloc (struct elf_link_hash_entry *h, void * xdata)
{
  bfd_vma *entry = (bfd_vma *) xdata;

  if (h->plt.offset != (bfd_vma) -1)
    {
      h->plt.offset = *entry;
      *entry += 4;
    }

  return TRUE;
}

static bfd_boolean
xstormy16_elf_relax_section (bfd *dynobj,
			     asection *splt,
			     struct bfd_link_info *info,
			     bfd_boolean *again)
{
  struct relax_plt_data relax_plt_data;
  bfd *ibfd;

  /* Assume nothing changes.  */
  *again = FALSE;

  if (info->relocatable)
    return TRUE;

  /* We only relax the .plt section at the moment.  */
  if (dynobj != elf_hash_table (info)->dynobj
      || strcmp (splt->name, ".plt") != 0)
    return TRUE;

  /* Quick check for an empty plt.  */
  if (splt->size == 0)
    return TRUE;

  /* Map across all global symbols; see which ones happen to
     fall in the low 64k.  */
  relax_plt_data.splt = splt;
  relax_plt_data.again = again;
  elf_link_hash_traverse (elf_hash_table (info), xstormy16_relax_plt_check,
			  &relax_plt_data);

  /* Likewise for local symbols, though that's somewhat less convenient
     as we have to walk the list of input bfds and swap in symbol data.  */
  for (ibfd = info->input_bfds; ibfd ; ibfd = ibfd->link_next)
    {
      bfd_vma *local_plt_offsets = elf_local_got_offsets (ibfd);
      Elf_Internal_Shdr *symtab_hdr;
      Elf_Internal_Sym *isymbuf = NULL;
      unsigned int idx;

      if (! local_plt_offsets)
	continue;

      symtab_hdr = &elf_tdata (ibfd)->symtab_hdr;
      if (symtab_hdr->sh_info != 0)
	{
	  isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
	  if (isymbuf == NULL)
	    isymbuf = bfd_elf_get_elf_syms (ibfd, symtab_hdr,
					    symtab_hdr->sh_info, 0,
					    NULL, NULL, NULL);
	  if (isymbuf == NULL)
	    return FALSE;
	}

      for (idx = 0; idx < symtab_hdr->sh_info; ++idx)
	{
	  Elf_Internal_Sym *isym;
	  asection *tsec;
	  bfd_vma address;

	  if (local_plt_offsets[idx] == (bfd_vma) -1)
	    continue;

	  isym = &isymbuf[idx];
	  if (isym->st_shndx == SHN_UNDEF)
	    continue;
	  else if (isym->st_shndx == SHN_ABS)
	    tsec = bfd_abs_section_ptr;
	  else if (isym->st_shndx == SHN_COMMON)
	    tsec = bfd_com_section_ptr;
	  else
	    tsec = bfd_section_from_elf_index (ibfd, isym->st_shndx);

	  address = (tsec->output_section->vma
		     + tsec->output_offset
		     + isym->st_value);
	  if (address <= 0xffff)
	    {
	      local_plt_offsets[idx] = -1;
	      splt->size -= 4;
	      *again = TRUE;
	    }
	}

      if (isymbuf != NULL
	  && symtab_hdr->contents != (unsigned char *) isymbuf)
	{
	  if (! info->keep_memory)
	    free (isymbuf);
	  else
	    {
	      /* Cache the symbols for elf_link_input_bfd.  */
	      symtab_hdr->contents = (unsigned char *) isymbuf;
	    }
	}
    }

  /* If we changed anything, walk the symbols again to reallocate
     .plt entry addresses.  */
  if (*again && splt->size > 0)
    {
      bfd_vma entry = 0;

      elf_link_hash_traverse (elf_hash_table (info),
			      xstormy16_relax_plt_realloc, &entry);

      for (ibfd = info->input_bfds; ibfd ; ibfd = ibfd->link_next)
	{
	  bfd_vma *local_plt_offsets = elf_local_got_offsets (ibfd);
	  unsigned int nlocals = elf_tdata (ibfd)->symtab_hdr.sh_info;
	  unsigned int idx;

	  if (! local_plt_offsets)
	    continue;

	  for (idx = 0; idx < nlocals; ++idx)
	    if (local_plt_offsets[idx] != (bfd_vma) -1)
	      {
	        local_plt_offsets[idx] = entry;
		entry += 4;
	      }
	}
    }

  return TRUE;
}

static bfd_boolean
xstormy16_elf_always_size_sections (bfd *output_bfd ATTRIBUTE_UNUSED,
				    struct bfd_link_info *info)
{
  bfd *dynobj;
  asection *splt;

  if (info->relocatable)
    return TRUE;

  dynobj = elf_hash_table (info)->dynobj;
  if (dynobj == NULL)
    return TRUE;

  splt = bfd_get_linker_section (dynobj, ".plt");
  BFD_ASSERT (splt != NULL);

  splt->contents = bfd_zalloc (dynobj, splt->size);
  if (splt->contents == NULL)
    return FALSE;

  return TRUE;
}

/* Relocate an XSTORMY16 ELF section.

   The RELOCATE_SECTION function is called by the new ELF backend linker
   to handle the relocations for a section.

   The relocs are always passed as Rela structures; if the section
   actually uses Rel structures, the r_addend field will always be
   zero.

   This function is responsible for adjusting the section contents as
   necessary, and (if using Rela relocs and generating a relocatable
   output file) adjusting the reloc addend as necessary.

   This function does not have to worry about setting the reloc
   address or the reloc symbol index.

   LOCAL_SYMS is a pointer to the swapped in local symbols.

   LOCAL_SECTIONS is an array giving the section in the input file
   corresponding to the st_shndx field of each local symbol.

   The global hash table entry for the global symbols can be found
   via elf_sym_hashes (input_bfd).

   When generating relocatable output, this function must handle
   STB_LOCAL/STT_SECTION symbols specially.  The output symbol is
   going to be the section symbol corresponding to the output
   section, which means that the addend must be adjusted
   accordingly.  */

static bfd_boolean
xstormy16_elf_relocate_section (bfd *                   output_bfd ATTRIBUTE_UNUSED,
				struct bfd_link_info *  info,
				bfd *                   input_bfd,
				asection *              input_section,
				bfd_byte *              contents,
				Elf_Internal_Rela *     relocs,
				Elf_Internal_Sym *      local_syms,
				asection **             local_sections)
{
  Elf_Internal_Shdr *           symtab_hdr;
  struct elf_link_hash_entry ** sym_hashes;
  Elf_Internal_Rela *           rel;
  Elf_Internal_Rela *           relend;
  bfd *dynobj;
  asection *splt;

  symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
  sym_hashes = elf_sym_hashes (input_bfd);
  relend     = relocs + input_section->reloc_count;

  dynobj = elf_hash_table (info)->dynobj;
  splt = NULL;
  if (dynobj != NULL)
    splt = bfd_get_linker_section (dynobj, ".plt");

  for (rel = relocs; rel < relend; rel ++)
    {
      reloc_howto_type *           howto;
      unsigned long                r_symndx;
      Elf_Internal_Sym *           sym;
      asection *                   sec;
      struct elf_link_hash_entry * h;
      bfd_vma                      relocation;
      bfd_reloc_status_type        r;
      const char *                 name = NULL;
      int                          r_type;

      r_type = ELF32_R_TYPE (rel->r_info);

      if (   r_type == R_XSTORMY16_GNU_VTINHERIT
	  || r_type == R_XSTORMY16_GNU_VTENTRY)
	continue;

      r_symndx = ELF32_R_SYM (rel->r_info);
      howto  = xstormy16_elf_howto_table + ELF32_R_TYPE (rel->r_info);
      h      = NULL;
      sym    = NULL;
      sec    = NULL;

      if (r_symndx < symtab_hdr->sh_info)
	{
	  sym = local_syms + r_symndx;
	  sec = local_sections [r_symndx];
	  relocation = _bfd_elf_rela_local_sym (output_bfd, sym, &sec, rel);
	}
      else
	{
	  bfd_boolean unresolved_reloc, warned;

	  RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
				   r_symndx, symtab_hdr, sym_hashes,
				   h, sec, relocation,
				   unresolved_reloc, warned);
	}

      if (sec != NULL && discarded_section (sec))
	RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section,
					 rel, 1, relend, howto, 0, contents);

      if (info->relocatable)
	continue;

      if (h != NULL)
	name = h->root.root.string;
      else
	{
	  name = (bfd_elf_string_from_elf_section
		  (input_bfd, symtab_hdr->sh_link, sym->st_name));
	  if (name == NULL || *name == '\0')
	    name = bfd_section_name (input_bfd, sec);
	}

      switch (ELF32_R_TYPE (rel->r_info))
	{
	case R_XSTORMY16_24:
	  {
	    bfd_vma reloc = relocation + rel->r_addend;
	    unsigned int x;

	    x = bfd_get_32 (input_bfd, contents + rel->r_offset);
	    x &= 0x0000ff00;
	    x |= reloc & 0xff;
	    x |= (reloc << 8) & 0xffff0000;
	    bfd_put_32 (input_bfd, x, contents + rel->r_offset);

	    if (reloc & ~0xffffff)
	      r = bfd_reloc_overflow;
	    else
	      r = bfd_reloc_ok;
	    break;
	  }

	case R_XSTORMY16_FPTR16:
	  {
	    bfd_vma *plt_offset;

	    if (h != NULL)
	      plt_offset = &h->plt.offset;
	    else
	      plt_offset = elf_local_got_offsets (input_bfd) + r_symndx;

	    if (relocation <= 0xffff)
	      {
	        /* If the symbol is in range for a 16-bit address, we should
		   have deallocated the plt entry in relax_section.  */
	        BFD_ASSERT (*plt_offset == (bfd_vma) -1);
	      }
	    else
	      {
		/* If the symbol is out of range for a 16-bit address,
		   we must have allocated a plt entry.  */
		BFD_ASSERT (*plt_offset != (bfd_vma) -1);

		/* If this is the first time we've processed this symbol,
		   fill in the plt entry with the correct symbol address.  */
		if ((*plt_offset & 1) == 0)
		  {
		    unsigned int x;

		    x = 0x00000200;  /* jmpf */
		    x |= relocation & 0xff;
		    x |= (relocation << 8) & 0xffff0000;
		    bfd_put_32 (input_bfd, x, splt->contents + *plt_offset);
		    *plt_offset |= 1;
		  }

		relocation = (splt->output_section->vma
			      + splt->output_offset
			      + (*plt_offset & -2));
	      }
	    r = _bfd_final_link_relocate (howto, input_bfd, input_section,
					  contents, rel->r_offset,
					  relocation, 0);
	    break;
	  }

	default:
	  r = _bfd_final_link_relocate (howto, input_bfd, input_section,
					contents, rel->r_offset,
					relocation, rel->r_addend);
	  break;
	}

      if (r != bfd_reloc_ok)
	{
	  const char * msg = NULL;

	  switch (r)
	    {
	    case bfd_reloc_overflow:
	      r = info->callbacks->reloc_overflow
		(info, (h ? &h->root : NULL), name, howto->name,
		 (bfd_vma) 0, input_bfd, input_section, rel->r_offset);
	      break;

	    case bfd_reloc_undefined:
	      r = info->callbacks->undefined_symbol
		(info, name, input_bfd, input_section, rel->r_offset,
		 TRUE);
	      break;

	    case bfd_reloc_outofrange:
	      msg = _("internal error: out of range error");
	      break;

	    case bfd_reloc_notsupported:
	      msg = _("internal error: unsupported relocation error");
	      break;

	    case bfd_reloc_dangerous:
	      msg = _("internal error: dangerous relocation");
	      break;

	    default:
	      msg = _("internal error: unknown error");
	      break;
	    }

	  if (msg)
	    r = info->callbacks->warning
	      (info, msg, name, input_bfd, input_section, rel->r_offset);

	  if (! r)
	    return FALSE;
	}
    }

  return TRUE;
}

/* This must exist if dynobj is ever set.  */

static bfd_boolean
xstormy16_elf_finish_dynamic_sections (bfd *abfd ATTRIBUTE_UNUSED,
				       struct bfd_link_info *info)
{
  bfd *dynobj;
  asection *splt;

  /* As an extra sanity check, verify that all plt entries have
     been filled in.  */

  if ((dynobj = elf_hash_table (info)->dynobj) != NULL
      && (splt = bfd_get_linker_section (dynobj, ".plt")) != NULL)
    {
      bfd_byte *contents = splt->contents;
      unsigned int i, size = splt->size;

      for (i = 0; i < size; i += 4)
	{
	  unsigned int x = bfd_get_32 (dynobj, contents + i);

	  BFD_ASSERT (x != 0);
	}
    }

  return TRUE;
}

/* Return the section that should be marked against GC for a given
   relocation.  */

static asection *
xstormy16_elf_gc_mark_hook (asection *sec,
			    struct bfd_link_info *info,
			    Elf_Internal_Rela *rel,
			    struct elf_link_hash_entry *h,
			    Elf_Internal_Sym *sym)
{
  if (h != NULL)
    switch (ELF32_R_TYPE (rel->r_info))
      {
      case R_XSTORMY16_GNU_VTINHERIT:
      case R_XSTORMY16_GNU_VTENTRY:
	return NULL;
      }

  return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym);
}

#define ELF_ARCH		bfd_arch_xstormy16
#define ELF_MACHINE_CODE	EM_XSTORMY16
#define ELF_MAXPAGESIZE		0x100

#define TARGET_LITTLE_SYM       bfd_elf32_xstormy16_vec
#define TARGET_LITTLE_NAME	"elf32-xstormy16"

#define elf_info_to_howto_rel			NULL
#define elf_info_to_howto			xstormy16_info_to_howto_rela
#define elf_backend_relocate_section		xstormy16_elf_relocate_section
#define elf_backend_gc_mark_hook		xstormy16_elf_gc_mark_hook
#define elf_backend_check_relocs                xstormy16_elf_check_relocs
#define elf_backend_always_size_sections \
  xstormy16_elf_always_size_sections
#define elf_backend_omit_section_dynsym \
  ((bfd_boolean (*) (bfd *, struct bfd_link_info *, asection *)) bfd_true)
#define elf_backend_finish_dynamic_sections \
  xstormy16_elf_finish_dynamic_sections

#define elf_backend_can_gc_sections		1
#define elf_backend_rela_normal			1

#define bfd_elf32_bfd_reloc_type_lookup		xstormy16_reloc_type_lookup
#define bfd_elf32_bfd_reloc_name_lookup \
  xstormy16_reloc_name_lookup
#define bfd_elf32_bfd_relax_section		xstormy16_elf_relax_section

#include "elf32-target.h"