elf32-cris.c

来自「基于4个mips核的noc设计」· C语言 代码 · 共 713 行 · 第 1/2 页

		   sym->st_value, rel->r_addend);
#endif
	}
      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;

	  name = h->root.root.string;

	  if (h->root.type == bfd_link_hash_defined
	      || h->root.type == bfd_link_hash_defweak)
	    {
	      sec = h->root.u.def.section;
	      relocation = (h->root.u.def.value
			    + sec->output_section->vma
			    + sec->output_offset);
#if 0
	      fprintf (stderr,
		       "defined: sec: %s, name: %s, value: %x + %x + %x gives: %x\n",
		       sec->name, name, h->root.u.def.value,
		       sec->output_section->vma, sec->output_offset, relocation);
#endif
	    }
	  else if (h->root.type == bfd_link_hash_undefweak)
	    {
#if 0
	      fprintf (stderr, "undefined: sec: %s, name: %s\n",
		       sec->name, name);
#endif
	      relocation = 0;
	    }
	  else if (info->shared
		   && ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
	    relocation = 0;
	  else
	    {
	      if (! ((*info->callbacks->undefined_symbol)
		     (info, h->root.root.string, input_bfd,
		      input_section, rel->r_offset, true)))
		return false;
#if 0
	      fprintf (stderr, "unknown: name: %s\n", name);
#endif
	      relocation = 0;
	    }
	}

      r = cris_final_link_relocate (howto, input_bfd, input_section,
				     contents, rel, relocation);

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

	  switch (r)
	    {
	    case bfd_reloc_overflow:
	      r = info->callbacks->reloc_overflow
		(info, 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;
}

/* Return the section that should be marked against GC for a given
   relocation.  */

static asection *
cris_elf_gc_mark_hook (abfd, info, rel, h, sym)
     bfd *                        abfd;
     struct bfd_link_info *       info ATTRIBUTE_UNUSED;
     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_CRIS_GNU_VTINHERIT:
	case R_CRIS_GNU_VTENTRY:
	  break;

	default:
	  switch (h->root.type)
	    {
	    case bfd_link_hash_defined:
	    case bfd_link_hash_defweak:
	      return h->root.u.def.section;

	    case bfd_link_hash_common:
	      return h->root.u.c.p->section;

	    default:
	      break;
	    }
	}
    }
  else
    {
      if (!(elf_bad_symtab (abfd)
	    && ELF_ST_BIND (sym->st_info) != STB_LOCAL)
	  && ! ((sym->st_shndx <= 0 || sym->st_shndx >= SHN_LORESERVE)
		&& sym->st_shndx != SHN_COMMON))
	{
	  return bfd_section_from_elf_index (abfd, sym->st_shndx);
	}
    }

  return NULL;
}

/* Update the got entry reference counts for the section being removed.  */

static boolean
cris_elf_gc_sweep_hook (abfd, info, sec, relocs)
     bfd *                     abfd ATTRIBUTE_UNUSED;
     struct bfd_link_info *    info ATTRIBUTE_UNUSED;
     asection *                sec ATTRIBUTE_UNUSED;
     const Elf_Internal_Rela * relocs ATTRIBUTE_UNUSED;
{
  return true;
}

/* 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 boolean
cris_elf_check_relocs (abfd, info, sec, 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, **sym_hashes_end;
  const Elf_Internal_Rela *rel;
  const Elf_Internal_Rela *rel_end;

  if (info->relocateable)
    return true;

  symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
  sym_hashes = elf_sym_hashes (abfd);
  sym_hashes_end = sym_hashes + symtab_hdr->sh_size/sizeof (Elf32_External_Sym);
  if (!elf_bad_symtab (abfd))
    sym_hashes_end -= symtab_hdr->sh_info;

  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];

      switch (ELF32_R_TYPE (rel->r_info))
        {
        /* This relocation describes the C++ object vtable hierarchy.
           Reconstruct it for later use during GC.  */
        case R_CRIS_GNU_VTINHERIT:
          if (!_bfd_elf32_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_CRIS_GNU_VTENTRY:
          if (!_bfd_elf32_gc_record_vtentry (abfd, sec, h, rel->r_addend))
            return false;
          break;
        }
    }

  return true;
}

/* Reject a file depending on underscores on symbols.  */

static boolean
cris_elf_object_p (abfd)
     bfd *abfd;
{
  if ((elf_elfheader (abfd)->e_flags & EF_CRIS_UNDERSCORE))
    return (bfd_get_symbol_leading_char (abfd) == '_');
  else
    return (bfd_get_symbol_leading_char (abfd) == 0);
}

/* Mark presence or absence of leading underscore.  */

static void
cris_elf_final_write_processing (abfd, linker)
     bfd *abfd;
     boolean linker ATTRIBUTE_UNUSED;
{
  if (bfd_get_symbol_leading_char (abfd) == '_')
    elf_elfheader (abfd)->e_flags |= EF_CRIS_UNDERSCORE;
  else
    elf_elfheader (abfd)->e_flags &= ~EF_CRIS_UNDERSCORE;
}

/* Display the flags field.  */

static boolean
cris_elf_print_private_bfd_data (abfd, ptr)
     bfd *abfd;
     PTR ptr;
{
  FILE *file = (FILE *) ptr;

  BFD_ASSERT (abfd != NULL && ptr != NULL)

  _bfd_elf_print_private_bfd_data (abfd, ptr);

  fprintf (file, _("private flags = %lx:"), elf_elfheader (abfd)->e_flags);

  if (elf_elfheader (abfd)->e_flags & EF_CRIS_UNDERSCORE)
    fprintf (file, _(" [symbols have a _ prefix]"));

  fputc ('\n', file);
  return true;
}

/* Don't mix files with and without a leading underscore.  */

static boolean
cris_elf_merge_private_bfd_data (ibfd, obfd)
     bfd *ibfd;
     bfd *obfd;
{
  flagword old_flags, new_flags;

  if (_bfd_generic_verify_endian_match (ibfd, obfd) == false)
    return false;

  if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour
      || bfd_get_flavour (obfd) != bfd_target_elf_flavour)
    return true;

  if (! elf_flags_init (obfd))
    {
      /* This happens when ld starts out with a 'blank' output file.  */
      elf_flags_init (obfd) = true;

      /* Set flags according to current bfd_target.  */
      cris_elf_final_write_processing (obfd, false);
    }

  old_flags = elf_elfheader (obfd)->e_flags;
  new_flags = elf_elfheader (ibfd)->e_flags;

  /* Is this good or bad?  We'll follow with other excluding flags.  */
  if ((old_flags & EF_CRIS_UNDERSCORE) != (new_flags & EF_CRIS_UNDERSCORE))
    {
      (*_bfd_error_handler)
	((new_flags & EF_CRIS_UNDERSCORE)
	 ? _("%s: uses _-prefixed symbols, but writing file with non-prefixed symbols")
	 : _("%s: uses non-prefixed symbols, but writing file with _-prefixed symbols"),
	 bfd_get_filename (ibfd));
      bfd_set_error (bfd_error_bad_value);
      return false;
    }

  return true;
}

#define ELF_ARCH		bfd_arch_cris
#define ELF_MACHINE_CODE	EM_CRIS
#define ELF_MAXPAGESIZE		0x2000

#define TARGET_LITTLE_SYM	bfd_elf32_cris_vec
#define TARGET_LITTLE_NAME	"elf32-cris"
#define elf_symbol_leading_char 0

#define elf_info_to_howto_rel			NULL
#define elf_info_to_howto			cris_info_to_howto_rela
#define elf_backend_relocate_section		cris_elf_relocate_section
#define elf_backend_gc_mark_hook		cris_elf_gc_mark_hook
#define elf_backend_gc_sweep_hook		cris_elf_gc_sweep_hook
#define elf_backend_check_relocs                cris_elf_check_relocs

#define elf_backend_can_gc_sections		1

#define elf_backend_object_p			cris_elf_object_p
#define elf_backend_final_write_processing \
	cris_elf_final_write_processing
#define bfd_elf32_bfd_print_private_bfd_data \
	cris_elf_print_private_bfd_data
#define bfd_elf32_bfd_merge_private_bfd_data \
	cris_elf_merge_private_bfd_data

#define bfd_elf32_bfd_reloc_type_lookup		cris_reloc_type_lookup

/* Later, we my want to optimize RELA entries into REL entries for dynamic
   linking and libraries (if it's a win of any significance).  Until then,
   take the easy route.  */
#define elf_backend_may_use_rel_p 0
#define elf_backend_may_use_rela_p 1

#include "elf32-target.h"

#define INCLUDED_TARGET_FILE

#undef TARGET_LITTLE_SYM
#undef TARGET_LITTLE_NAME
#undef elf_symbol_leading_char

#define TARGET_LITTLE_SYM bfd_elf32_us_cris_vec
#define TARGET_LITTLE_NAME "elf32-us-cris"
#define elf_symbol_leading_char '_'

#include "elf32-target.h"