elf32-i370.c

来自「基于4个mips核的noc设计」· C语言 代码 · 共 1,723 行 · 第 1/4 页

    i370_elf_howto_init ();

  local_got_offsets = elf_local_got_offsets (input_bfd);

  for (; rel < relend; rel++)
    {
      enum i370_reloc_type r_type	= (enum i370_reloc_type)ELF32_R_TYPE (rel->r_info);
      bfd_vma offset			= rel->r_offset;
      bfd_vma addend			= rel->r_addend;
      bfd_reloc_status_type r		= bfd_reloc_other;
      Elf_Internal_Sym *sym		= (Elf_Internal_Sym *)0;
      asection *sec			= (asection *)0;
      struct elf_link_hash_entry *h	= (struct elf_link_hash_entry *)0;
      const char *sym_name		= (const char *)0;
      reloc_howto_type *howto;
      unsigned long r_symndx;
      bfd_vma relocation;

      /* Unknown relocation handling */
      if ((unsigned)r_type >= (unsigned)R_I370_max
	  || !i370_elf_howto_table[(int)r_type])
	{
	  (*_bfd_error_handler) ("%s: unknown relocation type %d",
				 bfd_get_filename (input_bfd),
				 (int)r_type);

	  bfd_set_error (bfd_error_bad_value);
	  ret = false;
	  continue;
	}

      howto = i370_elf_howto_table[(int)r_type];
      r_symndx = ELF32_R_SYM (rel->r_info);

      if (info->relocateable)
	{
	  /* This is a relocateable link.  We don't have to change
	     anything, unless the reloc is against a section symbol,
	     in which case we have to adjust according to where the
	     section symbol winds up in the output section.  */
	  if (r_symndx < symtab_hdr->sh_info)
	    {
	      sym = local_syms + r_symndx;
	      if ((unsigned)ELF_ST_TYPE (sym->st_info) == STT_SECTION)
		{
		  sec = local_sections[r_symndx];
		  addend = rel->r_addend += sec->output_offset + sym->st_value;
		}
	    }

#ifdef DEBUG
	  fprintf (stderr, "\ttype = %s (%d), symbol index = %ld, offset = %ld, addend = %ld\n",
		   howto->name,
		   (int)r_type,
		   r_symndx,
		   (long)offset,
		   (long)addend);
#endif
	  continue;
	}

      /* This is a final link.  */
      if (r_symndx < symtab_hdr->sh_info)
	{
	  sym = local_syms + r_symndx;
	  sec = local_sections[r_symndx];
	  sym_name = "<local symbol>";

	  relocation = (sec->output_section->vma
			+ sec->output_offset
			+ sym->st_value);
	}
      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;
	  sym_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;
	      if (info->shared
		  && ((! info->symbolic && h->dynindx != -1)
		      || (h->elf_link_hash_flags
			  & ELF_LINK_HASH_DEF_REGULAR) == 0)
		  && (input_section->flags & SEC_ALLOC) != 0
		  && (r_type == R_I370_ADDR31
		      || r_type == R_I370_COPY
		      || r_type == R_I370_ADDR16
		      || r_type == R_I370_RELATIVE))
		{
		  /* In these cases, we don't need the relocation
                     value.  We check specially because in some
                     obscure cases sec->output_section will be NULL.  */
		  relocation = 0;
		}
	      else
		relocation = (h->root.u.def.value
			      + sec->output_section->vma
			      + sec->output_offset);
	    }
	  else if (h->root.type == bfd_link_hash_undefweak)
	    relocation = 0;
	  else if (info->shared
		   && ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
	    relocation = 0;
	  else
	    {
	      (*info->callbacks->undefined_symbol) (info,
						    h->root.root.string,
						    input_bfd,
						    input_section,
						    rel->r_offset,
						    true);
	      ret = false;
	      continue;
	    }
	}

      switch ((int)r_type)
	{
	default:
	  (*_bfd_error_handler) ("%s: unknown relocation type %d for symbol %s",
				 bfd_get_filename (input_bfd),
				 (int)r_type, sym_name);

	  bfd_set_error (bfd_error_bad_value);
	  ret = false;
	  continue;

	/* Relocations that may need to be propagated if this is a shared
           object.  */
	case (int)R_I370_REL31:
	  /* If these relocations are not to a named symbol, they can be
	     handled right here, no need to bother the dynamic linker.  */
	  if (h == NULL
	      || strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0)
	    break;
	/* fall through */

	/* Relocations that always need to be propagated if this is a shared
           object.  */
	case (int)R_I370_NONE:
	case (int)R_I370_ADDR31:
	case (int)R_I370_ADDR16:
	  if (info->shared)
	    {
	      Elf_Internal_Rela outrel;
	      boolean skip;

#ifdef DEBUG
	      fprintf (stderr,
		       "i370_elf_relocate_section needs to create relocation for %s\n",
		       (h && h->root.root.string) ? h->root.root.string : "<unknown>");
#endif

	      /* When generating a shared object, these relocations
                 are copied into the output file to be resolved at run
                 time.  */

	      if (sreloc == NULL)
		{
		  const char *name;

		  name = (bfd_elf_string_from_elf_section
			  (input_bfd,
			   elf_elfheader (input_bfd)->e_shstrndx,
			   elf_section_data (input_section)->rel_hdr.sh_name));
		  if (name == NULL)
		    return false;

		  BFD_ASSERT (strncmp (name, ".rela", 5) == 0
			      && strcmp (bfd_get_section_name (input_bfd,
							       input_section),
					 name + 5) == 0);

		  sreloc = bfd_get_section_by_name (dynobj, name);
		  BFD_ASSERT (sreloc != NULL);
		}

	      skip = false;

	      if (elf_section_data (input_section)->stab_info == NULL)
		outrel.r_offset = rel->r_offset;
	      else
		{
		  bfd_vma off;

		  off = (_bfd_stab_section_offset
			 (output_bfd, &elf_hash_table (info)->stab_info,
			  input_section,
			  &elf_section_data (input_section)->stab_info,
			  rel->r_offset));
		  if (off == (bfd_vma) -1)
		    skip = true;
		  outrel.r_offset = off;
		}

	      outrel.r_offset += (input_section->output_section->vma
				  + input_section->output_offset);

	      if (skip)
		memset (&outrel, 0, sizeof outrel);
	      /* h->dynindx may be -1 if this symbol was marked to
                 become local.  */
	      else if (h != NULL
		       && ((! info->symbolic && h->dynindx != -1)
			   || (h->elf_link_hash_flags
			       & ELF_LINK_HASH_DEF_REGULAR) == 0))
		{
		  BFD_ASSERT (h->dynindx != -1);
		  outrel.r_info = ELF32_R_INFO (h->dynindx, r_type);
		  outrel.r_addend = rel->r_addend;
		}
	      else
		{
		  if (r_type == R_I370_ADDR31)
		    {
		      outrel.r_info = ELF32_R_INFO (0, R_I370_RELATIVE);
		      outrel.r_addend = relocation + rel->r_addend;
		    }
		  else
		    {
		      long indx;

		      if (h == NULL)
			sec = local_sections[r_symndx];
		      else
			{
			  BFD_ASSERT (h->root.type == bfd_link_hash_defined
				      || (h->root.type
					  == bfd_link_hash_defweak));
			  sec = h->root.u.def.section;
			}
		      if (sec != NULL && bfd_is_abs_section (sec))
			indx = 0;
		      else if (sec == NULL || sec->owner == NULL)
			{
			  bfd_set_error (bfd_error_bad_value);
			  return false;
			}
		      else
			{
			  asection *osec;

			  osec = sec->output_section;
			  indx = elf_section_data (osec)->dynindx;
			  BFD_ASSERT(indx > 0);
#ifdef DEBUG
			  if (indx <= 0)
			    {
			      printf ("indx=%d section=%s flags=%08x name=%s\n",
				      indx, osec->name, osec->flags,
				      h->root.root.string);
			    }
#endif
			}

		      outrel.r_info = ELF32_R_INFO (indx, r_type);
		      outrel.r_addend = relocation + rel->r_addend;
		    }
		}

	      bfd_elf32_swap_reloca_out (output_bfd, &outrel,
					 (((Elf32_External_Rela *)
					   sreloc->contents)
					  + sreloc->reloc_count));
	      ++sreloc->reloc_count;

	      /* This reloc will be computed at runtime, so there's no
                 need to do anything now, unless this is a RELATIVE
                 reloc in an unallocated section.  */
	      if (skip
		  || (input_section->flags & SEC_ALLOC) != 0
		  || ELF32_R_TYPE (outrel.r_info) != R_I370_RELATIVE)
		continue;
	    }
	  break;

	case (int)R_I370_COPY:
	case (int)R_I370_RELATIVE:
	  (*_bfd_error_handler) ("%s: Relocation %s is not yet supported for symbol %s.",
				 bfd_get_filename (input_bfd),
				 i370_elf_howto_table[ (int)r_type ]->name,
				 sym_name);

	  bfd_set_error (bfd_error_invalid_operation);
	  ret = false;
	  continue;
	}

#ifdef DEBUG
      fprintf (stderr, "\ttype = %s (%d), name = %s, symbol index = %ld, offset = %ld, addend = %ld\n",
	       howto->name,
	       (int)r_type,
	       sym_name,
	       r_symndx,
	       (long)offset,
	       (long)addend);
#endif

      r = _bfd_final_link_relocate (howto,
				    input_bfd,
				    input_section,
				    contents,
				    offset,
				    relocation,
				    addend);

      if (r != bfd_reloc_ok)
	{
	  ret = false;
	  switch (r)
	    {
	    default:
	      break;

	    case bfd_reloc_overflow:
	      {
		const char *name;

		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)
		      break;

		    if (*name == '\0')
		      name = bfd_section_name (input_bfd, sec);
		  }

		(*info->callbacks->reloc_overflow) (info,
						    name,
						    howto->name,
						    (bfd_vma) 0,
						    input_bfd,
						    input_section,
						    offset);
	      }
	      break;

	    }
	}
    }

#ifdef DEBUG
  fprintf (stderr, "\n");
#endif

  return ret;
}

static void
i370_elf_post_process_headers (abfd, link_info)
    bfd * abfd;
    struct bfd_link_info * link_info ATTRIBUTE_UNUSED;
{
  Elf_Internal_Ehdr * i_ehdrp;  /* Elf file header, internal form */

  i_ehdrp = elf_elfheader (abfd);
  i_ehdrp->e_ident[EI_OSABI] = ELFOSABI_LINUX;
}

#define TARGET_BIG_SYM		bfd_elf32_i370_vec
#define TARGET_BIG_NAME		"elf32-i370"
#define ELF_ARCH		bfd_arch_i370
#define ELF_MACHINE_CODE	EM_S370
#ifdef EM_I370_OLD
#define ELF_MACHINE_ALT1	EM_I370_OLD
#endif
#define ELF_MAXPAGESIZE		0x1000
#define elf_info_to_howto	i370_elf_info_to_howto

#define elf_backend_plt_not_loaded 1
#define elf_backend_got_symbol_offset 4

#define bfd_elf32_bfd_reloc_type_lookup		i370_elf_reloc_type_lookup
#define bfd_elf32_bfd_set_private_flags		i370_elf_set_private_flags
#define bfd_elf32_bfd_copy_private_bfd_data	i370_elf_copy_private_bfd_data
#define bfd_elf32_bfd_merge_private_bfd_data	i370_elf_merge_private_bfd_data
#define elf_backend_relocate_section		i370_elf_relocate_section

/* dynamic loader support is mostly broken; just enough here to be able to
 * link glibc's ld.so without errors.
 */
#define elf_backend_create_dynamic_sections	i370_elf_create_dynamic_sections
#define elf_backend_size_dynamic_sections	i370_elf_size_dynamic_sections
#define elf_backend_finish_dynamic_sections	i370_elf_finish_dynamic_sections
#define elf_backend_fake_sections		i370_elf_fake_sections
#define elf_backend_section_from_shdr		i370_elf_section_from_shdr
#define elf_backend_adjust_dynamic_symbol	i370_elf_adjust_dynamic_symbol
#define elf_backend_check_relocs		i370_elf_check_relocs

/*
#define elf_backend_add_symbol_hook		i370_elf_add_symbol_hook
#define elf_backend_finish_dynamic_symbol	i370_elf_finish_dynamic_symbol
#define elf_backend_additional_program_headers	i370_elf_additional_program_headers
#define elf_backend_modify_segment_map		i370_elf_modify_segment_map
*/

#define elf_backend_post_process_headers	i370_elf_post_process_headers

int i370_noop()
{
  return 1;
}

/* we need to define these at least as no-ops to link glibc ld.so */

#define elf_backend_add_symbol_hook \
  (boolean (*) PARAMS ((bfd *, struct bfd_link_info *, \
			const Elf_Internal_Sym *, const char **, flagword *, \
			asection **, bfd_vma *))) 		i370_noop
#define elf_backend_finish_dynamic_symbol \
  (boolean (*) PARAMS ((bfd *, struct bfd_link_info *, \
			struct elf_link_hash_entry *, \
			Elf_Internal_Sym *)))			i370_noop
#define elf_backend_additional_program_headers \
  (int (*) PARAMS ((bfd *)))					i370_noop
#define elf_backend_modify_segment_map \
  (boolean (*) PARAMS ((bfd *)))				i370_noop

#include "elf32-target.h"