xref: /src/external/gpl3/binutils/dist/bfd/elf32-d10v.c

/* D10V-specific support for 32-bit ELF
   Copyright 1996, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
   2007, 2010, 2012 Free Software Foundation, Inc.
   Contributed by Martin Hunt (hunt (at) 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/d10v.h"

/* Use REL instead of RELA to save space.  */
#define USE_REL	1

static reloc_howto_type elf_d10v_howto_table[] =
{
  /* This reloc does nothing.  */
  HOWTO (R_D10V_NONE,		/* 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_D10V_NONE",		/* Name.  */
	 FALSE,			/* Partial_inplace.  */
	 0,			/* Src_mask.  */
	 0,			/* Dst_mask.  */
	 FALSE),		/* PCrel_offset.  */

  /* An PC Relative 10-bit relocation, shifted by 2, right container.  */
  HOWTO (R_D10V_10_PCREL_R,	/* Type.  */
	 2,	                /* Rightshift.  */
	 2,	                /* 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_D10V_10_PCREL_R",	/* Name.  */
	 FALSE,	        	/* Partial_inplace.  */
	 0xff,			/* Src_mask.  */
	 0xff,   		/* Dst_mask.  */
	 TRUE),			/* PCrel_offset.  */

  /* An PC Relative 10-bit relocation, shifted by 2, left container.  */
  HOWTO (R_D10V_10_PCREL_L,	/* Type.  */
	 2,	                /* Rightshift.  */
	 2,	                /* Size (0 = byte, 1 = short, 2 = long).  */
	 8,	                /* Bitsize.  */
	 TRUE,	        	/* PC_relative.  */
	 15,	                /* Bitpos.  */
	 complain_overflow_signed, /* Complain_on_overflow.  */
	 bfd_elf_generic_reloc, /* Special_function.  */
	 "R_D10V_10_PCREL_L",	/* Name.  */
	 FALSE,	        	/* Partial_inplace.  */
	 0x07f8000,		/* Src_mask.  */
	 0x07f8000,   		/* Dst_mask.  */
	 TRUE),			/* PCrel_offset.  */

  /* A 16 bit absolute relocation.  */
  HOWTO (R_D10V_16,		/* 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_D10V_16",		/* Name.  */
	 FALSE,			/* Partial_inplace.  */
	 0xffff,		/* Src_mask.  */
	 0xffff,		/* Dst_mask.  */
	 FALSE),		/* PCrel_offset.  */

  /* An 18 bit absolute relocation, right shifted 2.  */
  HOWTO (R_D10V_18,		/* Type.  */
	 2,			/* 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_D10V_18",		/* Name.  */
	 FALSE,			/* Partial_inplace.  */
	 0xffff,		/* Src_mask.  */
	 0xffff,		/* Dst_mask.  */
	 FALSE),		/* PCrel_offset.  */

  /* A relative 18 bit relocation, right shifted by 2.  */
  HOWTO (R_D10V_18_PCREL,	/* Type.  */
	 2,			/* Rightshift.  */
	 2,			/* 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_D10V_18_PCREL",	/* Name.  */
	 FALSE,			/* Partial_inplace.  */
	 0xffff,		/* Src_mask.  */
	 0xffff,		/* Dst_mask.  */
	 TRUE),			/* PCrel_offset.  */

  /* A 32 bit absolute relocation.  */
  HOWTO (R_D10V_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_D10V_32",		/* Name.  */
	 FALSE,			/* Partial_inplace.  */
	 0xffffffff,		/* Src_mask.  */
	 0xffffffff,		/* Dst_mask.  */
	 FALSE),		/* PCrel_offset.  */

  /* GNU extension to record C++ vtable hierarchy.  */
  HOWTO (R_D10V_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_D10V_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_D10V_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_D10V_GNU_VTENTRY",  /* Name.  */
	 FALSE,                 /* Partial_inplace.  */
	 0,                     /* Src_mask.  */
	 0,                     /* Dst_mask.  */
	 FALSE),                /* PCrel_offset.  */
};

/* Map BFD reloc types to D10V ELF reloc types.  */

struct d10v_reloc_map
{
  bfd_reloc_code_real_type bfd_reloc_val;
  unsigned char elf_reloc_val;
};

static const struct d10v_reloc_map d10v_reloc_map[] =
{
  { BFD_RELOC_NONE, R_D10V_NONE, },
  { BFD_RELOC_D10V_10_PCREL_R, R_D10V_10_PCREL_R },
  { BFD_RELOC_D10V_10_PCREL_L, R_D10V_10_PCREL_L },
  { BFD_RELOC_16, R_D10V_16 },
  { BFD_RELOC_D10V_18, R_D10V_18 },
  { BFD_RELOC_D10V_18_PCREL, R_D10V_18_PCREL },
  { BFD_RELOC_32, R_D10V_32 },
  { BFD_RELOC_VTABLE_INHERIT, R_D10V_GNU_VTINHERIT },
  { BFD_RELOC_VTABLE_ENTRY, R_D10V_GNU_VTENTRY },
};

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 = 0;
       i < sizeof (d10v_reloc_map) / sizeof (struct d10v_reloc_map);
       i++)
    if (d10v_reloc_map[i].bfd_reloc_val == code)
      return &elf_d10v_howto_table[d10v_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_d10v_howto_table) / sizeof (elf_d10v_howto_table[0]);
       i++)
    if (elf_d10v_howto_table[i].name != NULL
	&& strcasecmp (elf_d10v_howto_table[i].name, r_name) == 0)
      return &elf_d10v_howto_table[i];

  return NULL;
}

/* Set the howto pointer for an D10V ELF reloc.  */

static void
d10v_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_D10V_max);
  cache_ptr->howto = &elf_d10v_howto_table[r_type];
}

static asection *
elf32_d10v_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_D10V_GNU_VTINHERIT:
      case R_D10V_GNU_VTENTRY:
	return NULL;
      }

  return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym);
}

/* Look through the relocs for a section during the first phase.
   Since we don't do .gots or .plts, we just need to consider the
   virtual table relocs for gc.  */

static bfd_boolean
elf32_d10v_check_relocs (bfd *abfd,
			 struct bfd_link_info *info,
			 asection *sec,
			 const Elf_Internal_Rela *relocs)
{
  Elf_Internal_Shdr *symtab_hdr;
  struct elf_link_hash_entry **sym_hashes;
  const Elf_Internal_Rela *rel;
  const Elf_Internal_Rela *rel_end;

  if (info->relocatable)
    return TRUE;

  symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
  sym_hashes = elf_sym_hashes (abfd);

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

      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 the C++ object vtable hierarchy.
           Reconstruct it for later use during GC.  */
        case R_D10V_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_D10V_GNU_VTENTRY:
          BFD_ASSERT (h != NULL);
          if (h != NULL
              && !bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_offset))
            return FALSE;
          break;
        }
    }

  return TRUE;
}

static bfd_vma
extract_rel_addend (bfd *abfd,
		    bfd_byte *where,
		    reloc_howto_type *howto)
{
  bfd_vma insn, val;

  switch (howto->size)
    {
    case 0:
      insn = bfd_get_8 (abfd, where);
      break;
    case 1:
      insn = bfd_get_16 (abfd, where);
      break;
    case 2:
      insn = bfd_get_32 (abfd, where);
      break;
    default:
      abort ();
    }

  val = (insn & howto->dst_mask) >> howto->bitpos << howto->rightshift;
  /* We should really be testing for signed addends here, but we don't
     have that info directly in the howto.  */
  if (howto->pc_relative)
    {
      bfd_vma sign;
      sign = howto->dst_mask & (~howto->dst_mask >> 1 | ~(-(bfd_vma) 1 >> 1));
      sign = sign >> howto->bitpos << howto->rightshift;
      val = (val ^ sign) - sign;
    }
  return val;
}

static void
insert_rel_addend (bfd *abfd,
		   bfd_byte *where,
		   reloc_howto_type *howto,
		   bfd_vma addend)
{
  bfd_vma insn;

  addend = (addend >> howto->rightshift << howto->bitpos) & howto->dst_mask;
  insn = ~howto->dst_mask;
  switch (howto->size)
    {
    case 0:
      insn &= bfd_get_8 (abfd, where);
      insn |= addend;
      bfd_put_8 (abfd, insn, where);
      break;
    case 1:
      insn &= bfd_get_16 (abfd, where);
      insn |= addend;
      bfd_put_16 (abfd, insn, where);
      break;
    case 2:
      insn &= bfd_get_32 (abfd, where);
      insn |= addend;
      bfd_put_32 (abfd, insn, where);
      break;
    default:
      abort ();
    }
}

/* Relocate a D10V ELF section.  */

static bfd_boolean
elf32_d10v_relocate_section (bfd *output_bfd,
			     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, *relend;
  const char *name;

  symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
  sym_hashes = elf_sym_hashes (input_bfd);

  rel = relocs;
  relend = relocs + input_section->reloc_count;
  for (; rel < relend; rel++)
    {
      int r_type;
      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;

      r_symndx = ELF32_R_SYM (rel->r_info);
      r_type = ELF32_R_TYPE (rel->r_info);

      if (r_type == R_D10V_GNU_VTENTRY
          || r_type == R_D10V_GNU_VTINHERIT)
        continue;

      howto = elf_d10v_howto_table + r_type;
      h = NULL;
      sym = NULL;
      sec = NULL;
      if (r_symndx < symtab_hdr->sh_info)
	{
	  sym = local_syms + r_symndx;
	  sec = local_sections[r_symndx];
	  relocation = (sec->output_section->vma
			+ sec->output_offset
			+ sym->st_value);
	  if (ELF_ST_TYPE (sym->st_info) == STT_SECTION
	      && ((sec->flags & SEC_MERGE) != 0
		  || (info->relocatable
		      && sec->output_offset != 0)))
	    {
	      bfd_vma addend;
	      bfd_byte *where = contents + rel->r_offset;

	      addend = extract_rel_addend (input_bfd, where, howto);

	      if (info->relocatable)
		addend += sec->output_offset;
	      else
		{
		  asection *msec = sec;
		  addend = _bfd_elf_rel_local_sym (output_bfd, sym, &msec,
						   addend);
		  addend -= relocation;
		  addend += msec->output_section->vma + msec->output_offset;
		}
	      insert_rel_addend (input_bfd, where, howto, addend);
	    }
	}
      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);
	}

      r = _bfd_final_link_relocate (howto, input_bfd, input_section,
                                    contents, rel->r_offset,
                                    relocation, (bfd_vma) 0);

      if (r != bfd_reloc_ok)
	{
	  const char * msg = (const char *) 0;

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

	    case bfd_reloc_undefined:
	      if (!((*info->callbacks->undefined_symbol)
		    (info, name, input_bfd, input_section,
		     rel->r_offset, TRUE)))
		return FALSE;
	      break;

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

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

	    case bfd_reloc_dangerous:
	      msg = _("internal error: dangerous error");
	      goto common_error;

	    default:
	      msg = _("internal error: unknown error");
	      /* fall through */

	    common_error:
	      if (!((*info->callbacks->warning)
		    (info, msg, name, input_bfd, input_section,
		     rel->r_offset)))
		return FALSE;
	      break;
	    }
	}
    }

  return TRUE;
}
#define ELF_ARCH		bfd_arch_d10v
#define ELF_MACHINE_CODE	EM_D10V
#define ELF_MACHINE_ALT1	EM_CYGNUS_D10V
#define ELF_MAXPAGESIZE		0x1000

#define TARGET_BIG_SYM          bfd_elf32_d10v_vec
#define TARGET_BIG_NAME		"elf32-d10v"

#define elf_info_to_howto	             0
#define elf_info_to_howto_rel	             d10v_info_to_howto_rel
#define elf_backend_object_p	             0
#define elf_backend_final_write_processing   0
#define elf_backend_gc_mark_hook             elf32_d10v_gc_mark_hook
#define elf_backend_check_relocs             elf32_d10v_check_relocs
#define elf_backend_relocate_section         elf32_d10v_relocate_section
#define elf_backend_can_gc_sections          1

#include "elf32-target.h"