Re: ld on irix revisited

[Richard Sandiford <rsandifo at redhat dot com>]

While trying out these patches on trunk, I noticed that there are more
problems with .msym.  For one thing, it's bigger than it ought to be,
although the extra zero bytes are probably harmless.

More importantly, the ABI says that the hash table size must be a power
of 2 when .msym is present.  ld doesn't honour that.

Thiemo asked me to send an updated patch to either fix the problems
or drop the section.  All in all, I think dropping it would be best.
It is optional after all.

So, the patch below gets rid of the most of the .msym code.
I've kept bits in a few functions:

  - _bfd_mips_elf_section_from_shdr (interpret SHT_MIPS_MSYM sections)
  - _bfd_mips_elf_fake_sections (set type and alignment of .msym)
  - _bfd_mips_elf_finish_dynamic_sections (set value of DT_MIPS_MSYM)
  - _bfd_mips_elf_final_write_processing (set .msym's sh_link)

I don't know whether all these are still needed are not, but there
is similar code for other sections (like .liblist and .conflict)
that bfd doesn't create itself.  Could someone more familiar with
bfd double-check?

The patch replaces parts 4 and 5 from:

    http://sources.redhat.com/ml/binutils/2003-06/msg00724.html

The rest still stand.  Tested on mips-sgi-irix6.5 in combination
with the others, on HEAD rather than 2.14 this time.

If this is too invasive, or just plain wrong, an alternative
would be to use the second patch posted here:

    http://sources.redhat.com/ml/binutils/2003-06/msg00525.html

Richard


	* elfxx-mips.c (mips_elf_link_hash_entry): Remove min_dyn_reloc_index.
	(bfd_mips_elf_swap_msym_in, bfd_mips_elf_swap_msym_out): Delete.
	(mips_elf_create_msym_section): Delete.
	(mips_elf_create_dynamic_relocation): Don't set min_dyn_reloc_index.
	(_bfd_mips_elf_copy_indirect_symbol): Likewise.
	(_bfd_mips_elf_create_dynamic_sections): Don't create .msym.
	(_bfd_mips_elf_size_dynamic_sections): Don't calculate its size.
	(_bfd_mips_elf_size_dynamic_sections): Don't add DT_MIPS_MSYM.
	(_bfd_mips_elf_finish_dynamic_symbol): Don't add symbols to .msym.
	(_bfd_mips_elf_finish_dynamic_sections): Likewise.

Index: bfd/elfxx-mips.c
===================================================================
RCS file: /cvs/src/src/bfd/elfxx-mips.c,v
retrieving revision 1.63
diff -u -d -p -F^\([(a-zA-Z0-9_]\|#define\) -r1.63 elfxx-mips.c
--- bfd/elfxx-mips.c	28 Jun 2003 22:13:37 -0000	1.63
+++ bfd/elfxx-mips.c	29 Jun 2003 09:42:53 -0000
@@ -188,10 +188,6 @@ struct mips_elf_link_hash_entry
      a readonly section.  */
   bfd_boolean readonly_reloc;
 
-  /* The index of the first dynamic relocation (in the .rel.dyn
-     section) against this symbol.  */
-  unsigned int min_dyn_reloc_index;
-
   /* We must not create a stub for a symbol that has relocations
      related to taking the function's address, i.e. any but
      R_MIPS_CALL*16 ones -- see "MIPS ABI Supplement, 3rd Edition",
@@ -390,12 +386,6 @@ static void bfd_elf32_swap_compact_rel_o
   PARAMS ((bfd *, const Elf32_compact_rel *, Elf32_External_compact_rel *));
 static void bfd_elf32_swap_crinfo_out
   PARAMS ((bfd *, const Elf32_crinfo *, Elf32_External_crinfo *));
-#if 0
-static void bfd_mips_elf_swap_msym_in
-  PARAMS ((bfd *, const Elf32_External_Msym *, Elf32_Internal_Msym *));
-#endif
-static void bfd_mips_elf_swap_msym_out
-  PARAMS ((bfd *, const Elf32_Internal_Msym *, Elf32_External_Msym *));
 static int sort_dynamic_relocs
   PARAMS ((const void *, const void *));
 static int sort_dynamic_relocs_64
@@ -442,8 +432,6 @@ static bfd_boolean mips_elf_create_compa
   PARAMS ((bfd *, struct bfd_link_info *));
 static bfd_boolean mips_elf_create_got_section
   PARAMS ((bfd *, struct bfd_link_info *, bfd_boolean));
-static asection *mips_elf_create_msym_section
-  PARAMS ((bfd *));
 static bfd_reloc_status_type mips_elf_calculate_relocation
   PARAMS ((bfd *, bfd *, asection *, struct bfd_link_info *,
 	   const Elf_Internal_Rela *, bfd_vma, reloc_howto_type *,
@@ -730,7 +718,6 @@ mips_elf_link_hash_newfunc (entry, table
       ret->esym.ifd = -2;
       ret->possibly_dynamic_relocs = 0;
       ret->readonly_reloc = FALSE;
-      ret->min_dyn_reloc_index = 0;
       ret->no_fn_stub = FALSE;
       ret->fn_stub = NULL;
       ret->need_fn_stub = FALSE;
@@ -1192,31 +1179,6 @@ bfd_elf32_swap_crinfo_out (abfd, in, ex)
   H_PUT_32 (abfd, in->konst, ex->konst);
   H_PUT_32 (abfd, in->vaddr, ex->vaddr);
 }
-
-#if 0
-/* Swap in an MSYM entry.  */
-
-static void
-bfd_mips_elf_swap_msym_in (abfd, ex, in)
-     bfd *abfd;
-     const Elf32_External_Msym *ex;
-     Elf32_Internal_Msym *in;
-{
-  in->ms_hash_value = H_GET_32 (abfd, ex->ms_hash_value);
-  in->ms_info = H_GET_32 (abfd, ex->ms_info);
-}
-#endif
-/* Swap out an MSYM entry.  */
-
-static void
-bfd_mips_elf_swap_msym_out (abfd, in, ex)
-     bfd *abfd;
-     const Elf32_Internal_Msym *in;
-     Elf32_External_Msym *ex;
-{
-  H_PUT_32 (abfd, in->ms_hash_value, ex->ms_hash_value);
-  H_PUT_32 (abfd, in->ms_info, ex->ms_info);
-}
 
 /* A .reginfo section holds a single Elf32_RegInfo structure.  These
    routines swap this structure in and out.  They are used outside of
@@ -2917,34 +2879,6 @@ mips_elf_create_got_section (abfd, info,
 
   return TRUE;
 }
-
-/* Returns the .msym section for ABFD, creating it if it does not
-   already exist.  Returns NULL to indicate error.  */
-
-static asection *
-mips_elf_create_msym_section (abfd)
-     bfd *abfd;
-{
-  asection *s;
-
-  s = bfd_get_section_by_name (abfd, ".msym");
-  if (!s)
-    {
-      s = bfd_make_section (abfd, ".msym");
-      if (!s
-	  || !bfd_set_section_flags (abfd, s,
-				     SEC_ALLOC
-				     | SEC_LOAD
-				     | SEC_HAS_CONTENTS
-				     | SEC_LINKER_CREATED
-				     | SEC_READONLY)
-	  || !bfd_set_section_alignment (abfd, s,
-					 MIPS_ELF_LOG_FILE_ALIGN (abfd)))
-	return NULL;
-    }
-
-  return s;
-}
 
 /* Calculate the value produced by the RELOCATION (which comes from
    the INPUT_BFD).  The ADDEND is the addend to use for this
@@ -3985,13 +3919,6 @@ mips_elf_create_dynamic_relocation (outp
       (output_bfd, &outrel[0],
        (sreloc->contents + sreloc->reloc_count * sizeof (Elf32_External_Rel)));
 
-  /* Record the index of the first relocation referencing H.  This
-     information is later emitted in the .msym section.  */
-  if (h != NULL
-      && (h->min_dyn_reloc_index == 0
-	  || sreloc->reloc_count < h->min_dyn_reloc_index))
-    h->min_dyn_reloc_index = sreloc->reloc_count;
-
   /* We've now added another relocation.  */
   ++sreloc->reloc_count;
 
@@ -4892,13 +4819,6 @@ _bfd_mips_elf_create_dynamic_sections (a
   if (! mips_elf_rel_dyn_section (elf_hash_table (info)->dynobj, TRUE))
     return FALSE;
 
-  /* Create the .msym section on IRIX6.  It is used by the dynamic
-     linker to speed up dynamic relocations, and to avoid computing
-     the ELF hash for symbols.  */
-  if (IRIX_COMPAT (abfd) == ict_irix6
-      && !mips_elf_create_msym_section (abfd))
-    return FALSE;
-
   /* Create .stub section.  */
   if (bfd_get_section_by_name (abfd,
 			       MIPS_ELF_STUB_SECTION_NAME (abfd)) == NULL)
@@ -6061,10 +5981,6 @@ _bfd_mips_elf_size_dynamic_sections (out
       else if (SGI_COMPAT (output_bfd)
 	       && strncmp (name, ".compact_rel", 12) == 0)
 	s->_raw_size += mips_elf_hash_table (info)->compact_rel_size;
-      else if (strcmp (name, ".msym") == 0)
-	s->_raw_size = (sizeof (Elf32_External_Msym)
-			* (elf_hash_table (info)->dynsymcount
-			   + bfd_count_sections (output_bfd)));
       else if (strncmp (name, ".init", 5) != 0)
 	{
 	  /* It's not one of our sections, so don't allocate space.  */
@@ -6209,10 +6125,6 @@ _bfd_mips_elf_size_dynamic_sections (out
 	      (dynobj, MIPS_ELF_OPTIONS_SECTION_NAME (dynobj)))
 	  && !MIPS_ELF_ADD_DYNAMIC_ENTRY (info, DT_MIPS_OPTIONS, 0))
 	return FALSE;
-
-      if (bfd_get_section_by_name (dynobj, ".msym")
-	  && !MIPS_ELF_ADD_DYNAMIC_ENTRY (info, DT_MIPS_MSYM, 0))
-	return FALSE;
     }
 
   return TRUE;
@@ -6669,14 +6581,11 @@ _bfd_mips_elf_finish_dynamic_symbol (out
   bfd *dynobj;
   bfd_vma gval;
   asection *sgot;
-  asection *smsym;
   struct mips_got_info *g, *gg;
   const char *name;
-  struct mips_elf_link_hash_entry *mh;
 
   dynobj = elf_hash_table (info)->dynobj;
   gval = sym->st_value;
-  mh = (struct mips_elf_link_hash_entry *) h;
 
   if (h->plt.offset != (bfd_vma) -1)
     {
@@ -6805,21 +6714,6 @@ _bfd_mips_elf_finish_dynamic_symbol (out
 	}
     }
 
-  /* Create a .msym entry, if appropriate.  */
-  smsym = bfd_get_section_by_name (dynobj, ".msym");
-  if (smsym)
-    {
-      Elf32_Internal_Msym msym;
-
-      msym.ms_hash_value = bfd_elf_hash (h->root.root.string);
-      /* It is undocumented what the `1' indicates, but IRIX6 uses
-	 this value.  */
-      msym.ms_info = ELF32_MS_INFO (mh->min_dyn_reloc_index, 1);
-      bfd_mips_elf_swap_msym_out
-	(dynobj, &msym,
-	 ((Elf32_External_Msym *) smsym->contents) + h->dynindx);
-    }
-
   /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute.  */
   name = h->root.root.string;
   if (strcmp (name, "_DYNAMIC") == 0
@@ -7142,33 +7036,9 @@ _bfd_mips_elf_finish_dynamic_sections (o
     }
 
   {
-    asection *smsym;
     asection *s;
     Elf32_compact_rel cpt;
 
-    /* ??? The section symbols for the output sections were set up in
-       _bfd_elf_final_link.  SGI sets the STT_NOTYPE attribute for these
-       symbols.  Should we do so?  */
-
-    smsym = bfd_get_section_by_name (dynobj, ".msym");
-    if (smsym != NULL)
-      {
-	Elf32_Internal_Msym msym;
-
-	msym.ms_hash_value = 0;
-	msym.ms_info = ELF32_MS_INFO (0, 1);
-
-	for (s = output_bfd->sections; s != NULL; s = s->next)
-	  {
-	    long dynindx = elf_section_data (s)->dynindx;
-
-	    bfd_mips_elf_swap_msym_out
-	      (output_bfd, &msym,
-	       (((Elf32_External_Msym *) smsym->contents)
-		+ dynindx));
-	  }
-      }
-
     if (SGI_COMPAT (output_bfd))
       {
 	/* Write .compact_rel section out.  */
@@ -7761,10 +7631,6 @@ _bfd_mips_elf_copy_indirect_symbol (bed,
   dirmips->possibly_dynamic_relocs += indmips->possibly_dynamic_relocs;
   if (indmips->readonly_reloc)
     dirmips->readonly_reloc = TRUE;
-  if (dirmips->min_dyn_reloc_index == 0
-      || (indmips->min_dyn_reloc_index != 0
-	  && indmips->min_dyn_reloc_index < dirmips->min_dyn_reloc_index))
-    dirmips->min_dyn_reloc_index = indmips->min_dyn_reloc_index;
   if (indmips->no_fn_stub)
     dirmips->no_fn_stub = TRUE;
 }