/* ELF linker support.
- Copyright 1995, 1996, 1997 Free Software Foundation, Inc.
+ Copyright 1995, 1996, 1997, 1998 Free Software Foundation, Inc.
This file is part of BFD, the Binary File Descriptor library.
PARAMS ((struct elf_link_hash_entry *, PTR));
static boolean elf_link_renumber_dynsyms
PARAMS ((struct elf_link_hash_entry *, PTR));
+static boolean elf_collect_hash_codes
+ PARAMS ((struct elf_link_hash_entry *, PTR));
/* Given an ELF BFD, add symbols to the global hash table as
appropriate. */
boolean newdyn, olddyn, olddef, newdef, newdyncommon, olddyncommon;
*override = false;
- *type_change_ok = false;
- *size_change_ok = false;
sec = *psec;
bind = ELF_ST_BIND (sym->st_info);
}
sz = bfd_section_size (abfd, s);
- msg = (char *) bfd_alloc (abfd, sz);
+ msg = (char *) bfd_alloc (abfd, sz + 1);
if (msg == NULL)
goto error_return;
if (! bfd_get_section_contents (abfd, s, msg, (file_ptr) 0, sz))
goto error_return;
+ msg[sz] = '\0';
+
if (! (_bfd_generic_link_add_one_symbol
(info, abfd, name, BSF_WARNING, s, (bfd_vma) 0, msg,
false, collect, (struct bfd_link_hash_entry **) NULL)))
if (info->hash->creator->flavour == bfd_target_elf_flavour)
{
Elf_Internal_Versym iver;
- int vernum;
+ unsigned int vernum = 0;
boolean override;
if (ever != NULL)
if (vernum > elf_tdata (abfd)->dynverdef_hdr.sh_info)
{
(*_bfd_error_handler)
- ("%s: %s: invalid version %d (max %d)",
+ (_("%s: %s: invalid version %u (max %d)"),
abfd->filename, name, vernum,
elf_tdata (abfd)->dynverdef_hdr.sh_info);
bfd_set_error (bfd_error_bad_value);
if (verstr == NULL)
{
(*_bfd_error_handler)
- ("%s: %s: invalid needed version %d",
+ (_("%s: %s: invalid needed version %d"),
abfd->filename, name, vernum);
bfd_set_error (bfd_error_bad_value);
goto error_return;
{
if (h->size != 0 && h->size != sym.st_size && ! size_change_ok)
(*_bfd_error_handler)
- ("Warning: size of symbol `%s' changed from %lu to %lu in %s",
+ (_("Warning: size of symbol `%s' changed from %lu to %lu in %s"),
name, (unsigned long) h->size, (unsigned long) sym.st_size,
bfd_get_filename (abfd));
&& h->type != ELF_ST_TYPE (sym.st_info)
&& ! type_change_ok)
(*_bfd_error_handler)
- ("Warning: type of symbol `%s' changed from %d to %d in %s",
+ (_("Warning: type of symbol `%s' changed from %d to %d in %s"),
name, h->type, ELF_ST_TYPE (sym.st_info),
bfd_get_filename (abfd));
purposes of the merge, act as though we were
defining the symbol we just defined, although we
actually going to define an indirect symbol. */
+ type_change_ok = false;
+ size_change_ok = false;
if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
&value, &hi, &override,
&type_change_ok, &size_change_ok))
{
h->elf_link_hash_flags &=~ ELF_LINK_HASH_DEF_DYNAMIC;
hi->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
- if (! _bfd_elf_link_record_dynamic_symbol (info, hi))
- goto error_return;
+ if (hi->elf_link_hash_flags
+ & (ELF_LINK_HASH_REF_REGULAR
+ | ELF_LINK_HASH_DEF_REGULAR))
+ {
+ if (! _bfd_elf_link_record_dynamic_symbol (info,
+ hi))
+ goto error_return;
+ }
}
/* Now set HI to H, so that the following code
& (ELF_LINK_HASH_REF_DYNAMIC
| ELF_LINK_HASH_REF_REGULAR));
- /* Copy over the global table offset entry.
- This may have been already set up by a
- check_relocs routine. */
- if (ht->got_offset == (bfd_vma) -1)
+ /* Copy over the global and procedure linkage table
+ offset entries. These may have been already set
+ up by a check_relocs routine. */
+ if (ht->got.offset == (bfd_vma) -1)
{
- ht->got_offset = hi->got_offset;
- hi->got_offset = (bfd_vma) -1;
+ ht->got.offset = hi->got.offset;
+ hi->got.offset = (bfd_vma) -1;
}
- BFD_ASSERT (hi->got_offset == (bfd_vma) -1);
+ BFD_ASSERT (hi->got.offset == (bfd_vma) -1);
+
+ if (ht->plt.offset == (bfd_vma) -1)
+ {
+ ht->plt.offset = hi->plt.offset;
+ hi->plt.offset = (bfd_vma) -1;
+ }
+ BFD_ASSERT (hi->plt.offset == (bfd_vma) -1);
if (ht->dynindx == -1)
{
strcpy (shortname + (p - name), p + 1);
/* Once again, merge with any existing symbol. */
+ type_change_ok = false;
+ size_change_ok = false;
if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
&value, &hi, &override,
&type_change_ok, &size_change_ok))
don't expect to see the type of override we
do in the case above. */
(*_bfd_error_handler)
- ("%s: warning: unexpected redefinition of `%s'",
+ (_("%s: warning: unexpected redefinition of `%s'"),
bfd_get_filename (abfd), shortname);
}
else
& (ELF_LINK_HASH_REF_DYNAMIC
| ELF_LINK_HASH_REF_REGULAR));
- /* Copy over the global table offset entry.
- This may have been already set up by a
- check_relocs routine. */
- if (h->got_offset == (bfd_vma) -1)
+ /* Copy over the global and procedure linkage
+ table offset entries. These may have been
+ already set up by a check_relocs routine. */
+ if (h->got.offset == (bfd_vma) -1)
{
- h->got_offset = hi->got_offset;
- hi->got_offset = (bfd_vma) -1;
+ h->got.offset = hi->got.offset;
+ hi->got.offset = (bfd_vma) -1;
}
- BFD_ASSERT (hi->got_offset == (bfd_vma) -1);
+ BFD_ASSERT (hi->got.offset == (bfd_vma) -1);
+
+ if (h->plt.offset == (bfd_vma) -1)
+ {
+ h->plt.offset = hi->plt.offset;
+ hi->plt.offset = (bfd_vma) -1;
+ }
+ BFD_ASSERT (hi->got.offset == (bfd_vma) -1);
if (h->dynindx == -1)
{
16411, 32771, 0
};
+/* Compute bucket count for hashing table. We do not use a static set
+ of possible tables sizes anymore. Instead we determine for all
+ possible reasonable sizes of the table the outcome (i.e., the
+ number of collisions etc) and choose the best solution. The
+ weighting functions are not too simple to allow the table to grow
+ without bounds. Instead one of the weighting factors is the size.
+ Therefore the result is always a good payoff between few collisions
+ (= short chain lengths) and table size. */
+static size_t
+compute_bucket_count (info)
+ struct bfd_link_info *info;
+{
+ size_t dynsymcount = elf_hash_table (info)->dynsymcount;
+ size_t best_size;
+ unsigned long int *hashcodes;
+ unsigned long int *hashcodesp;
+ unsigned long int i;
+
+ /* Compute the hash values for all exported symbols. At the same
+ time store the values in an array so that we could use them for
+ optimizations. */
+ hashcodes = (unsigned long int *) bfd_malloc (dynsymcount
+ * sizeof (unsigned long int));
+ if (hashcodes == NULL)
+ return 0;
+ hashcodesp = hashcodes;
+
+ /* Put all hash values in HASHCODES. */
+ elf_link_hash_traverse (elf_hash_table (info),
+ elf_collect_hash_codes, &hashcodesp);
+
+/* We have a problem here. The following code to optimize the table
+ size requires an integer type with more the 32 bits. If
+ BFD_HOST_U_64_BIT is set we know about such a type. */
+#ifdef BFD_HOST_U_64_BIT
+ if (info->optimize == true)
+ {
+ unsigned long int nsyms = hashcodesp - hashcodes;
+ size_t minsize;
+ size_t maxsize;
+ BFD_HOST_U_64_BIT best_chlen = ~((BFD_HOST_U_64_BIT) 0);
+ unsigned long int *counts ;
+
+ /* Possible optimization parameters: if we have NSYMS symbols we say
+ that the hashing table must at least have NSYMS/4 and at most
+ 2*NSYMS buckets. */
+ minsize = nsyms / 4;
+ if (minsize == 0)
+ minsize = 1;
+ best_size = maxsize = nsyms * 2;
+
+ /* Create array where we count the collisions in. We must use bfd_malloc
+ since the size could be large. */
+ counts = (unsigned long int *) bfd_malloc (maxsize
+ * sizeof (unsigned long int));
+ if (counts == NULL)
+ {
+ free (hashcodes);
+ return 0;
+ }
+
+ /* Compute the "optimal" size for the hash table. The criteria is a
+ minimal chain length. The minor criteria is (of course) the size
+ of the table. */
+ for (i = minsize; i < maxsize; ++i)
+ {
+ /* Walk through the array of hashcodes and count the collisions. */
+ BFD_HOST_U_64_BIT max;
+ unsigned long int j;
+ unsigned long int fact;
+
+ memset (counts, '\0', i * sizeof (unsigned long int));
+
+ /* Determine how often each hash bucket is used. */
+ for (j = 0; j < nsyms; ++j)
+ ++counts[hashcodes[j] % i];
+
+ /* For the weight function we need some information about the
+ pagesize on the target. This is information need not be 100%
+ accurate. Since this information is not available (so far) we
+ define it here to a reasonable default value. If it is crucial
+ to have a better value some day simply define this value. */
+# ifndef BFD_TARGET_PAGESIZE
+# define BFD_TARGET_PAGESIZE (4096)
+# endif
+
+ /* We in any case need 2 + NSYMS entries for the size values and
+ the chains. */
+ max = (2 + nsyms) * (ARCH_SIZE / 8);
+
+# if 1
+ /* Variant 1: optimize for short chains. We add the squares
+ of all the chain lengths (which favous many small chain
+ over a few long chains). */
+ for (j = 0; j < i; ++j)
+ max += counts[j] * counts[j];
+
+ /* This adds penalties for the overall size of the table. */
+ fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1;
+ max *= fact * fact;
+# else
+ /* Variant 2: Optimize a lot more for small table. Here we
+ also add squares of the size but we also add penalties for
+ empty slots (the +1 term). */
+ for (j = 0; j < i; ++j)
+ max += (1 + counts[j]) * (1 + counts[j]);
+
+ /* The overall size of the table is considered, but not as
+ strong as in variant 1, where it is squared. */
+ fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1;
+ max *= fact;
+# endif
+
+ /* Compare with current best results. */
+ if (max < best_chlen)
+ {
+ best_chlen = max;
+ best_size = i;
+ }
+ }
+
+ free (counts);
+ }
+ else
+#endif /* defined (BFD_HOST_U_64_BIT) */
+ {
+ /* This is the fallback solution if no 64bit type is available or if we
+ are not supposed to spend much time on optimizations. We select the
+ bucket count using a fixed set of numbers. */
+ for (i = 0; elf_buckets[i] != 0; i++)
+ {
+ best_size = elf_buckets[i];
+ if (dynsymcount < elf_buckets[i + 1])
+ break;
+ }
+ }
+
+ /* Free the arrays we needed. */
+ free (hashcodes);
+
+ return best_size;
+}
+
/* Set up the sizes and contents of the ELF dynamic sections. This is
called by the ELF linker emulation before_allocation routine. We
must set the sizes of the sections before the linker sets the
*sinterpptr = NULL;
- soname_indx = -1;
+ soname_indx = (bfd_size_type) -1;
if (info->hash->creator->flavour != bfd_target_elf_flavour)
return true;
/* The backend must work out the sizes of all the other dynamic
sections. */
old_dynsymcount = elf_hash_table (info)->dynsymcount;
- if (! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
+ if (bed->elf_backend_size_dynamic_sections
+ && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
return false;
if (elf_hash_table (info)->dynamic_sections_created)
def.vd_next = (sizeof (Elf_External_Verdef)
+ sizeof (Elf_External_Verdaux));
- if (soname_indx != -1)
+ if (soname_indx != (bfd_size_type) -1)
{
def.vd_hash = bfd_elf_hash ((const unsigned char *) soname);
defaux.vda_name = soname_indx;
elf_swap_symbol_out (output_bfd, &isym,
(PTR) (Elf_External_Sym *) s->contents);
- for (i = 0; elf_buckets[i] != 0; i++)
- {
- bucketcount = elf_buckets[i];
- if (dynsymcount < elf_buckets[i + 1])
- break;
- }
+ /* Compute the size of the hashing table. As a side effect this
+ computes the hash values for all the names we export. */
+ bucketcount = compute_bucket_count (info);
s = bfd_get_section_by_name (dynobj, ".hash");
BFD_ASSERT (s != NULL);
}
}
}
+ else
+ {
+ /* Unfortunately, ELF_LINK_NON_ELF is only correct if the symbol
+ was first seen in a non-ELF file. Fortunately, if the symbol
+ was first seen in an ELF file, we're probably OK unless the
+ symbol was defined in a non-ELF file. Catch that case here.
+ FIXME: We're still in trouble if the symbol was first seen in
+ a dynamic object, and then later in a non-ELF regular object. */
+ if ((h->root.type == bfd_link_hash_defined
+ || h->root.type == bfd_link_hash_defweak)
+ && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
+ && (h->root.u.def.section->owner != NULL
+ ? (bfd_get_flavour (h->root.u.def.section->owner)
+ != bfd_target_elf_flavour)
+ : (bfd_is_abs_section (h->root.u.def.section)
+ && (h->elf_link_hash_flags
+ & ELF_LINK_HASH_DEF_DYNAMIC) == 0)))
+ h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
+ }
/* If this is a final link, and the symbol was defined as a common
symbol in a regular object file, and there was no definition in
&& eif->info->shared
&& eif->info->symbolic
&& (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
- h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
+ {
+ h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
+ h->plt.offset = (bfd_vma) -1;
+ }
return true;
}
|| (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
|| ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0
&& (h->weakdef == NULL || h->weakdef->dynindx == -1))))
- return true;
+ {
+ h->plt.offset = (bfd_vma) -1;
+ return true;
+ }
/* If we've already adjusted this symbol, don't do it again. This
can happen via a recursive call. */
}
}
+ /* If a symbol has no type and no size and does not require a PLT
+ entry, then we are probably about to do the wrong thing here: we
+ are probably going to create a COPY reloc for an empty object.
+ This case can arise when a shared object is built with assembly
+ code, and the assembly code fails to set the symbol type. */
+ if (h->size == 0
+ && h->type == STT_NOTYPE
+ && (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0)
+ (*_bfd_error_handler)
+ (_("warning: type and size of dynamic symbol `%s' are not defined"),
+ h->root.root.string);
+
dynobj = elf_hash_table (eif->info)->dynobj;
bed = get_elf_backend_data (dynobj);
if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
h->elf_link_hash_flags &=~
ELF_LINK_HASH_NEEDS_PLT;
h->dynindx = -1;
+ h->plt.offset = (bfd_vma) -1;
/* FIXME: The name of the symbol has
already been recorded in the dynamic
string table section. */
/* We could not find the version for a symbol when
generating a shared archive. Return an error. */
(*_bfd_error_handler)
- ("%s: undefined version name %s",
+ (_("%s: undefined versioned symbol name %s"),
bfd_get_filename (sinfo->output_bfd), h->root.root.string);
bfd_set_error (bfd_error_bad_value);
sinfo->failed = true;
h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
h->dynindx = -1;
+ h->plt.offset = (bfd_vma) -1;
/* FIXME: The name of the symbol has already
been recorded in the dynamic string table
section. */
h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
h->dynindx = -1;
+ h->plt.offset = (bfd_vma) -1;
/* FIXME: The name of the symbol has already been
recorded in the dynamic string table section. */
}
we could write the relocs out and then read them again; I don't
know how bad the memory loss will be. */
- for (sub = info->input_bfds; sub != NULL; sub = sub->next)
+ for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
sub->output_has_begun = false;
for (o = abfd->sections; o != NULL; o = o->next)
{
if (name == (const char *) NULL || *name == '\0')
elfsym->st_name = 0;
+ else if (input_sec->flags & SEC_EXCLUDE)
+ elfsym->st_name = 0;
else
{
elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
input_sec->output_section);
if (sym.st_shndx == (unsigned short) -1)
{
+ (*_bfd_error_handler)
+ (_("%s: could not find output section %s for input section %s"),
+ bfd_get_filename (finfo->output_bfd),
+ input_sec->output_section->name,
+ input_sec->name);
eoinfo->failed = true;
return false;
}
if (h->dynindx != -1
&& elf_hash_table (finfo->info)->dynamic_sections_created)
{
- char *p, *copy;
- const char *name;
size_t bucketcount;
size_t bucket;
bfd_byte *bucketpos;
finfo->dynsym_sec->contents)
+ h->dynindx));
- /* We didn't include the version string in the dynamic string
- table, so we must not consider it in the hash table. */
- name = h->root.root.string;
- p = strchr (name, ELF_VER_CHR);
- if (p == NULL)
- copy = NULL;
- else
- {
- copy = bfd_alloc (finfo->output_bfd, p - name + 1);
- strncpy (copy, name, p - name);
- copy[p - name] = '\0';
- name = copy;
- }
-
bucketcount = elf_hash_table (finfo->info)->bucketcount;
- bucket = bfd_elf_hash ((const unsigned char *) name) % bucketcount;
+ bucket = h->elf_hash_value % bucketcount;
bucketpos = ((bfd_byte *) finfo->hash_sec->contents
+ (bucket + 2) * (ARCH_SIZE / 8));
chain = get_word (finfo->output_bfd, bucketpos);
((bfd_byte *) finfo->hash_sec->contents
+ (bucketcount + 2 + h->dynindx) * (ARCH_SIZE / 8)));
- if (copy != NULL)
- bfd_release (finfo->output_bfd, copy);
-
if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL)
{
Elf_Internal_Versym iversym;
/* Write out the modified section contents. */
if (elf_section_data (o)->stab_info == NULL)
{
- if (! bfd_set_section_contents (output_bfd, o->output_section,
+ if (! (o->flags & SEC_EXCLUDE) &&
+ ! bfd_set_section_contents (output_bfd, o->output_section,
contents, o->output_offset,
(o->_cooked_size != 0
? o->_cooked_size
/* Allocate a table to hold the local symbols if first time */
if (!ptr)
{
- int num_symbols = elf_tdata (abfd)->symtab_hdr.sh_info;
+ unsigned int num_symbols = elf_tdata (abfd)->symtab_hdr.sh_info;
register unsigned int i;
ptr = (elf_linker_section_pointers_t **)
processing. */
return relocation - linker_section_ptr->addend;
}
+\f
+/* Garbage collect unused sections. */
+
+static boolean elf_gc_mark
+ PARAMS ((struct bfd_link_info *info, asection *sec,
+ asection * (*gc_mark_hook)
+ PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
+ struct elf_link_hash_entry *, Elf_Internal_Sym *))));
+
+static boolean elf_gc_sweep
+ PARAMS ((struct bfd_link_info *info,
+ boolean (*gc_sweep_hook)
+ PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
+ const Elf_Internal_Rela *relocs))));
+
+static boolean elf_gc_sweep_symbol
+ PARAMS ((struct elf_link_hash_entry *h, PTR idxptr));
+
+static boolean elf_gc_allocate_got_offsets
+ PARAMS ((struct elf_link_hash_entry *h, PTR offarg));
+
+static boolean elf_gc_propagate_vtable_entries_used
+ PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
+
+static boolean elf_gc_smash_unused_vtentry_relocs
+ PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
+
+/* The mark phase of garbage collection. For a given section, mark
+ it, and all the sections which define symbols to which it refers. */
+
+static boolean
+elf_gc_mark (info, sec, gc_mark_hook)
+ struct bfd_link_info *info;
+ asection *sec;
+ asection * (*gc_mark_hook)
+ PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
+ struct elf_link_hash_entry *, Elf_Internal_Sym *));
+{
+ boolean ret = true;
+
+ sec->gc_mark = 1;
+
+ /* Look through the section relocs. */
+
+ if ((sec->flags & SEC_RELOC) != 0 && sec->reloc_count > 0)
+ {
+ Elf_Internal_Rela *relstart, *rel, *relend;
+ Elf_Internal_Shdr *symtab_hdr;
+ struct elf_link_hash_entry **sym_hashes;
+ size_t nlocsyms;
+ size_t extsymoff;
+ Elf_External_Sym *locsyms, *freesyms = NULL;
+ bfd *input_bfd = sec->owner;
+
+ /* GCFIXME: how to arrange so that relocs and symbols are not
+ reread continually? */
+
+ symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
+ sym_hashes = elf_sym_hashes (input_bfd);
+
+ /* Read the local symbols. */
+ if (elf_bad_symtab (input_bfd))
+ {
+ nlocsyms = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
+ extsymoff = 0;
+ }
+ else
+ extsymoff = nlocsyms = symtab_hdr->sh_info;
+ if (symtab_hdr->contents)
+ locsyms = (Elf_External_Sym *) symtab_hdr->contents;
+ else if (nlocsyms == 0)
+ locsyms = NULL;
+ else
+ {
+ locsyms = freesyms =
+ bfd_malloc (nlocsyms * sizeof (Elf_External_Sym));
+ if (freesyms == NULL
+ || bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
+ || (bfd_read (locsyms, sizeof (Elf_External_Sym),
+ nlocsyms, input_bfd)
+ != nlocsyms * sizeof (Elf_External_Sym)))
+ {
+ ret = false;
+ goto out1;
+ }
+ }
+
+ /* Read the relocations. */
+ relstart = (NAME(_bfd_elf,link_read_relocs)
+ (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL,
+ info->keep_memory));
+ if (relstart == NULL)
+ {
+ ret = false;
+ goto out1;
+ }
+ relend = relstart + sec->reloc_count;
+
+ for (rel = relstart; rel < relend; rel++)
+ {
+ unsigned long r_symndx;
+ asection *rsec;
+ struct elf_link_hash_entry *h;
+ Elf_Internal_Sym s;
+
+ r_symndx = ELF_R_SYM (rel->r_info);
+ if (r_symndx == 0)
+ continue;
+
+ if (elf_bad_symtab (sec->owner))
+ {
+ elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
+ if (ELF_ST_BIND (s.st_info) == STB_LOCAL)
+ rsec = (*gc_mark_hook)(sec->owner, info, rel, NULL, &s);
+ else
+ {
+ h = sym_hashes[r_symndx - extsymoff];
+ rsec = (*gc_mark_hook)(sec->owner, info, rel, h, NULL);
+ }
+ }
+ else if (r_symndx >= nlocsyms)
+ {
+ h = sym_hashes[r_symndx - extsymoff];
+ rsec = (*gc_mark_hook)(sec->owner, info, rel, h, NULL);
+ }
+ else
+ {
+ elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
+ rsec = (*gc_mark_hook)(sec->owner, info, rel, NULL, &s);
+ }
+
+ if (rsec && !rsec->gc_mark)
+ if (!elf_gc_mark (info, rsec, gc_mark_hook))
+ {
+ ret = false;
+ goto out2;
+ }
+ }
+
+ out2:
+ if (!info->keep_memory)
+ free (relstart);
+ out1:
+ if (freesyms)
+ free (freesyms);
+ }
+
+ return ret;
+}
+
+/* The sweep phase of garbage collection. Remove all garbage sections. */
+
+static boolean
+elf_gc_sweep (info, gc_sweep_hook)
+ struct bfd_link_info *info;
+ boolean (*gc_sweep_hook)
+ PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
+ const Elf_Internal_Rela *relocs));
+{
+ bfd *sub;
+
+ for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
+ {
+ asection *o;
+
+ for (o = sub->sections; o != NULL; o = o->next)
+ {
+ /* Keep special sections. Keep .debug sections. */
+ if ((o->flags & SEC_LINKER_CREATED)
+ || (o->flags & SEC_DEBUGGING))
+ o->gc_mark = 1;
+
+ if (o->gc_mark)
+ continue;
+
+ /* Skip sweeping sections already excluded. */
+ if (o->flags & SEC_EXCLUDE)
+ continue;
+
+ /* Since this is early in the link process, it is simple
+ to remove a section from the output. */
+ o->flags |= SEC_EXCLUDE;
+
+ /* But we also have to update some of the relocation
+ info we collected before. */
+ if (gc_sweep_hook
+ && (o->flags & SEC_RELOC) && o->reloc_count > 0)
+ {
+ Elf_Internal_Rela *internal_relocs;
+ boolean r;
+
+ internal_relocs = (NAME(_bfd_elf,link_read_relocs)
+ (o->owner, o, NULL, NULL, info->keep_memory));
+ if (internal_relocs == NULL)
+ return false;
+
+ r = (*gc_sweep_hook)(o->owner, info, o, internal_relocs);
+
+ if (!info->keep_memory)
+ free (internal_relocs);
+
+ if (!r)
+ return false;
+ }
+ }
+ }
+
+ /* Remove the symbols that were in the swept sections from the dynamic
+ symbol table. GCFIXME: Anyone know how to get them out of the
+ static symbol table as well? */
+ {
+ int i = 0;
+
+ elf_link_hash_traverse (elf_hash_table (info),
+ elf_gc_sweep_symbol,
+ (PTR) &i);
+
+ elf_hash_table (info)->dynsymcount = i;
+ }
+
+ return true;
+}
+
+/* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */
+
+static boolean
+elf_gc_sweep_symbol (h, idxptr)
+ struct elf_link_hash_entry *h;
+ PTR idxptr;
+{
+ int *idx = (int *) idxptr;
+
+ if (h->dynindx != -1
+ && ((h->root.type != bfd_link_hash_defined
+ && h->root.type != bfd_link_hash_defweak)
+ || h->root.u.def.section->gc_mark))
+ h->dynindx = (*idx)++;
+
+ return true;
+}
+
+/* Propogate collected vtable information. This is called through
+ elf_link_hash_traverse. */
+
+static boolean
+elf_gc_propagate_vtable_entries_used (h, okp)
+ struct elf_link_hash_entry *h;
+ PTR okp;
+{
+ /* Those that are not vtables. */
+ if (h->vtable_parent == NULL)
+ return true;
+
+ /* Those vtables that do not have parents, we cannot merge. */
+ if (h->vtable_parent == (struct elf_link_hash_entry *) -1)
+ return true;
+
+ /* If we've already been done, exit. */
+ if (h->vtable_entries_used && h->vtable_entries_used[-1])
+ return true;
+
+ /* Make sure the parent's table is up to date. */
+ elf_gc_propagate_vtable_entries_used (h->vtable_parent, okp);
+
+ if (h->vtable_entries_used == NULL)
+ {
+ /* None of this table's entries were referenced. Re-use the
+ parent's table. */
+ h->vtable_entries_used = h->vtable_parent->vtable_entries_used;
+ h->vtable_entries_size = h->vtable_parent->vtable_entries_size;
+ }
+ else
+ {
+ size_t n;
+ boolean *cu, *pu;
+
+ /* Or the parent's entries into ours. */
+ cu = h->vtable_entries_used;
+ cu[-1] = true;
+ pu = h->vtable_parent->vtable_entries_used;
+ if (pu != NULL)
+ {
+ n = h->vtable_parent->vtable_entries_size / FILE_ALIGN;
+ while (--n != 0)
+ {
+ if (*pu) *cu = true;
+ pu++, cu++;
+ }
+ }
+ }
+
+ return true;
+}
+
+static boolean
+elf_gc_smash_unused_vtentry_relocs (h, okp)
+ struct elf_link_hash_entry *h;
+ PTR okp;
+{
+ asection *sec;
+ bfd_vma hstart, hend;
+ Elf_Internal_Rela *relstart, *relend, *rel;
+
+ /* Take care of both those symbols that do not describe vtables as
+ well as those that are not loaded. */
+ if (h->vtable_parent == NULL)
+ return true;
+
+ BFD_ASSERT (h->root.type == bfd_link_hash_defined
+ || h->root.type == bfd_link_hash_defweak);
+
+ sec = h->root.u.def.section;
+ hstart = h->root.u.def.value;
+ hend = hstart + h->size;
+
+ relstart = (NAME(_bfd_elf,link_read_relocs)
+ (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL, true));
+ if (!relstart)
+ return *(boolean *)okp = false;
+ relend = relstart + sec->reloc_count;
+
+ for (rel = relstart; rel < relend; ++rel)
+ if (rel->r_offset >= hstart && rel->r_offset < hend)
+ {
+ /* If the entry is in use, do nothing. */
+ if (h->vtable_entries_used
+ && (rel->r_offset - hstart) < h->vtable_entries_size)
+ {
+ bfd_vma entry = (rel->r_offset - hstart) / FILE_ALIGN;
+ if (h->vtable_entries_used[entry])
+ continue;
+ }
+ /* Otherwise, kill it. */
+ rel->r_offset = rel->r_info = rel->r_addend = 0;
+ }
+
+ return true;
+}
+
+/* Do mark and sweep of unused sections. */
+
+boolean
+elf_gc_sections (abfd, info)
+ bfd *abfd;
+ struct bfd_link_info *info;
+{
+ boolean ok = true;
+ bfd *sub;
+ asection * (*gc_mark_hook)
+ PARAMS ((bfd *abfd, struct bfd_link_info *, Elf_Internal_Rela *,
+ struct elf_link_hash_entry *h, Elf_Internal_Sym *));
+
+ if (!get_elf_backend_data (abfd)->can_gc_sections
+ || info->relocateable
+ || elf_hash_table (info)->dynamic_sections_created)
+ return true;
+
+ /* Apply transitive closure to the vtable entry usage info. */
+ elf_link_hash_traverse (elf_hash_table (info),
+ elf_gc_propagate_vtable_entries_used,
+ (PTR) &ok);
+ if (!ok)
+ return false;
+
+ /* Kill the vtable relocations that were not used. */
+ elf_link_hash_traverse (elf_hash_table (info),
+ elf_gc_smash_unused_vtentry_relocs,
+ (PTR) &ok);
+ if (!ok)
+ return false;
+
+ /* Grovel through relocs to find out who stays ... */
+
+ gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook;
+ for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
+ {
+ asection *o;
+ for (o = sub->sections; o != NULL; o = o->next)
+ {
+ if (o->flags & SEC_KEEP)
+ if (!elf_gc_mark (info, o, gc_mark_hook))
+ return false;
+ }
+ }
+
+ /* ... and mark SEC_EXCLUDE for those that go. */
+ if (!elf_gc_sweep(info, get_elf_backend_data (abfd)->gc_sweep_hook))
+ return false;
+
+ return true;
+}
+\f
+/* Called from check_relocs to record the existance of a VTINHERIT reloc. */
+
+boolean
+elf_gc_record_vtinherit (abfd, sec, h, offset)
+ bfd *abfd;
+ asection *sec;
+ struct elf_link_hash_entry *h;
+ bfd_vma offset;
+{
+ struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
+ struct elf_link_hash_entry **search, *child;
+ bfd_size_type extsymcount;
+
+ /* The sh_info field of the symtab header tells us where the
+ external symbols start. We don't care about the local symbols at
+ this point. */
+ extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size/sizeof (Elf_External_Sym);
+ if (!elf_bad_symtab (abfd))
+ extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
+
+ sym_hashes = elf_sym_hashes (abfd);
+ sym_hashes_end = sym_hashes + extsymcount;
+
+ /* Hunt down the child symbol, which is in this section at the same
+ offset as the relocation. */
+ for (search = sym_hashes; search != sym_hashes_end; ++search)
+ {
+ if ((child = *search) != NULL
+ && (child->root.type == bfd_link_hash_defined
+ || child->root.type == bfd_link_hash_defweak)
+ && child->root.u.def.section == sec
+ && child->root.u.def.value == offset)
+ goto win;
+ }
+
+ (*_bfd_error_handler) ("%s: %s+%lu: No symbol found for INHERIT",
+ bfd_get_filename (abfd), sec->name,
+ (unsigned long)offset);
+ bfd_set_error (bfd_error_invalid_operation);
+ return false;
+
+win:
+ if (!h)
+ {
+ /* This *should* only be the absolute section. It could potentially
+ be that someone has defined a non-global vtable though, which
+ would be bad. It isn't worth paging in the local symbols to be
+ sure though; that case should simply be handled by the assembler. */
+
+ child->vtable_parent = (struct elf_link_hash_entry *) -1;
+ }
+ else
+ child->vtable_parent = h;
+
+ return true;
+}
+
+/* Called from check_relocs to record the existance of a VTENTRY reloc. */
+
+boolean
+elf_gc_record_vtentry (abfd, sec, h, addend)
+ bfd *abfd;
+ asection *sec;
+ struct elf_link_hash_entry *h;
+ bfd_vma addend;
+{
+ if (addend >= h->vtable_entries_size)
+ {
+ size_t size, bytes;
+ boolean *ptr = h->vtable_entries_used;
+
+ /* While the symbol is undefined, we have to be prepared to handle
+ a zero size. */
+ if (h->root.type == bfd_link_hash_undefined)
+ size = addend;
+ else
+ {
+ size = h->size;
+ if (size < addend)
+ {
+ /* Oops! We've got a reference past the defined end of
+ the table. This is probably a bug -- shall we warn? */
+ size = addend;
+ }
+ }
+
+ /* Allocate one extra entry for use as a "done" flag for the
+ consolidation pass. */
+ bytes = (size / FILE_ALIGN + 1) * sizeof(boolean);
+
+ if (ptr)
+ {
+ size_t oldbytes;
+
+ ptr = realloc (ptr-1, bytes);
+ if (ptr == NULL)
+ return false;
+
+ oldbytes = (h->vtable_entries_size/FILE_ALIGN + 1) * sizeof(boolean);
+ memset (ptr + oldbytes, 0, bytes - oldbytes);
+ }
+ else
+ {
+ ptr = calloc (1, bytes);
+ if (ptr == NULL)
+ return false;
+ }
+
+ /* And arrange for that done flag to be at index -1. */
+ h->vtable_entries_used = ptr+1;
+ h->vtable_entries_size = size;
+ }
+ h->vtable_entries_used[addend / FILE_ALIGN] = true;
+
+ return true;
+}
+
+/* And an accompanying bit to work out final got entry offsets once
+ we're done. Should be called from final_link. */
+
+boolean
+elf_gc_common_finalize_got_offsets (abfd, info)
+ bfd *abfd;
+ struct bfd_link_info *info;
+{
+ bfd *i;
+ struct elf_backend_data *bed = get_elf_backend_data (abfd);
+ bfd_vma gotoff;
+
+ /* The GOT offset is relative to the .got section, but the GOT header is
+ put into the .got.plt section, if the backend uses it. */
+ if (bed->want_got_plt)
+ gotoff = 0;
+ else
+ gotoff = bed->got_header_size;
+
+ /* Do the local .got entries first. */
+ for (i = info->input_bfds; i; i = i->link_next)
+ {
+ bfd_signed_vma *local_got = elf_local_got_refcounts (i);
+ bfd_size_type j, locsymcount;
+ Elf_Internal_Shdr *symtab_hdr;
+
+ if (!local_got)
+ continue;
+
+ symtab_hdr = &elf_tdata (i)->symtab_hdr;
+ if (elf_bad_symtab (i))
+ locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
+ else
+ locsymcount = symtab_hdr->sh_info;
+
+ for (j = 0; j < locsymcount; ++j)
+ {
+ if (local_got[j] > 0)
+ {
+ local_got[j] = gotoff;
+ gotoff += ARCH_SIZE / 8;
+ }
+ else
+ local_got[j] = (bfd_vma) -1;
+ }
+ }
+
+ /* Then the global .got and .plt entries. */
+ elf_link_hash_traverse (elf_hash_table (info),
+ elf_gc_allocate_got_offsets,
+ (PTR) &gotoff);
+ return true;
+}
+
+/* We need a special top-level link routine to convert got reference counts
+ to real got offsets. */
+
+static boolean
+elf_gc_allocate_got_offsets (h, offarg)
+ struct elf_link_hash_entry *h;
+ PTR offarg;
+{
+ bfd_vma *off = (bfd_vma *) offarg;
+
+ if (h->got.refcount > 0)
+ {
+ h->got.offset = off[0];
+ off[0] += ARCH_SIZE / 8;
+ }
+ else
+ h->got.offset = (bfd_vma) -1;
+
+ return true;
+}
+
+/* Many folk need no more in the way of final link than this, once
+ got entry reference counting is enabled. */
+
+boolean
+elf_gc_common_final_link (abfd, info)
+ bfd *abfd;
+ struct bfd_link_info *info;
+{
+ if (!elf_gc_common_finalize_got_offsets (abfd, info))
+ return false;
+
+ /* Invoke the regular ELF backend linker to do all the work. */
+ return elf_bfd_final_link (abfd, info);
+}
+
+/* This function will be called though elf_link_hash_traverse to store
+ all hash value of the exported symbols in an array. */
+
+static boolean
+elf_collect_hash_codes (h, data)
+ struct elf_link_hash_entry *h;
+ PTR data;
+{
+ unsigned long **valuep = (unsigned long **) data;
+ const char *name;
+ char *p;
+ unsigned long ha;
+ char *alc = NULL;
+
+ /* Ignore indirect symbols. These are added by the versioning code. */
+ if (h->dynindx == -1)
+ return true;
+
+ name = h->root.root.string;
+ p = strchr (name, ELF_VER_CHR);
+ if (p != NULL)
+ {
+ alc = bfd_malloc (p - name + 1);
+ memcpy (alc, name, p - name);
+ alc[p - name] = '\0';
+ name = alc;
+ }
+
+ /* Compute the hash value. */
+ ha = bfd_elf_hash (name);
+
+ /* Store the found hash value in the array given as the argument. */
+ *(*valuep)++ = ha;
+
+ /* And store it in the struct so that we can put it in the hash table
+ later. */
+ h->elf_hash_value = ha;
+
+ if (alc != NULL)
+ free (alc);
+
+ return true;
+}
projects / thirdparty / binutils-gdb.git / blobdiff