/* X86-64 specific support for 64-bit ELF
- Copyright 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007
+ Copyright 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
Free Software Foundation, Inc.
Contributed by Jan Hubicka <jh@suse.cz>.
FALSE)
};
+#define IS_X86_64_PCREL_TYPE(TYPE) \
+ ( ((TYPE) == R_X86_64_PC8) \
+ || ((TYPE) == R_X86_64_PC16) \
+ || ((TYPE) == R_X86_64_PC32) \
+ || ((TYPE) == R_X86_64_PC64))
+
/* Map BFD relocs to the x86_64 elf relocs. */
struct elf_reloc_map
{
#define elf64_x86_64_local_tlsdesc_gotent(abfd) \
(elf64_x86_64_tdata (abfd)->local_tlsdesc_gotent)
+#define is_x86_64_elf(bfd) \
+ (bfd_get_flavour (bfd) == bfd_target_elf_flavour \
+ && elf_tdata (bfd) != NULL \
+ && elf_object_id (bfd) == X86_64_ELF_TDATA)
+
+static bfd_boolean
+elf64_x86_64_mkobject (bfd *abfd)
+{
+ return bfd_elf_allocate_object (abfd, sizeof (struct elf64_x86_64_obj_tdata),
+ X86_64_ELF_TDATA);
+}
+
/* x86-64 ELF linker hash table. */
struct elf64_x86_64_link_hash_table
/* Small local sym to section mapping cache. */
struct sym_sec_cache sym_sec;
+
+ /* _TLS_MODULE_BASE_ symbol. */
+ struct bfd_link_hash_entry *tls_module_base;
};
/* Get the x86-64 ELF linker hash table from a link_info structure. */
ret->tlsdesc_got = 0;
ret->tls_ld_got.refcount = 0;
ret->sgotplt_jump_table_size = 0;
+ ret->tls_module_base = NULL;
return &ret->elf.root;
}
}
static bfd_boolean
-elf64_x86_64_mkobject (bfd *abfd)
-{
- if (abfd->tdata.any == NULL)
- {
- bfd_size_type amt = sizeof (struct elf64_x86_64_obj_tdata);
- abfd->tdata.any = bfd_zalloc (abfd, amt);
- if (abfd->tdata.any == NULL)
- return FALSE;
- }
- return bfd_elf_mkobject (abfd);
-}
-
-static bfd_boolean
elf64_x86_64_elf_object_p (bfd *abfd)
{
/* Set the right machine number for an x86-64 elf64 file. */
return FALSE;
h = sym_hashes[r_symndx - symtab_hdr->sh_info];
+ /* Use strncmp to check __tls_get_addr since __tls_get_addr
+ may be versioned. */
return (h != NULL
&& h->root.root.string != NULL
&& (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PC32
|| ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32)
- && (strcmp (h->root.root.string, "__tls_get_addr") == 0));
+ && (strncmp (h->root.root.string,
+ "__tls_get_addr", 14) == 0));
case R_X86_64_GOTTPOFF:
/* Check transition from IE access model:
return TRUE;
}
+/* Returns true if the hash entry refers to a symbol
+ marked for indirect handling during reloc processing. */
+
+static bfd_boolean
+is_indirect_symbol (bfd * abfd, struct elf_link_hash_entry * h)
+{
+ const struct elf_backend_data * bed;
+
+ if (abfd == NULL || h == NULL)
+ return FALSE;
+
+ bed = get_elf_backend_data (abfd);
+
+ return h->type == STT_GNU_IFUNC
+ && (bed->elf_osabi == ELFOSABI_LINUX
+ /* GNU/Linux is still using the default value 0. */
+ || bed->elf_osabi == ELFOSABI_NONE);
+}
+
/* Look through the relocs for a section during the first phase, and
calculate needed space in the global offset table, procedure
linkage table, and dynamic reloc sections. */
if (info->relocatable)
return TRUE;
+ BFD_ASSERT (is_x86_64_elf (abfd));
+
htab = elf64_x86_64_hash_table (info);
- symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
+ symtab_hdr = &elf_symtab_hdr (abfd);
sym_hashes = elf_sym_hashes (abfd);
sreloc = NULL;
-
+
rel_end = relocs + sec->reloc_count;
for (rel = relocs; rel < rel_end; rel++)
{
symbol. */
if ((info->shared
&& (sec->flags & SEC_ALLOC) != 0
- && (((r_type != R_X86_64_PC8)
- && (r_type != R_X86_64_PC16)
- && (r_type != R_X86_64_PC32)
- && (r_type != R_X86_64_PC64))
+ && (! IS_X86_64_PCREL_TYPE (r_type)
|| (h != NULL
&& (! SYMBOLIC_BIND (info, h)
|| h->root.type == bfd_link_hash_defweak
this reloc. */
if (sreloc == NULL)
{
- const char *name;
- bfd *dynobj;
-
- name = (bfd_elf_string_from_elf_section
- (abfd,
- elf_elfheader (abfd)->e_shstrndx,
- elf_section_data (sec)->rel_hdr.sh_name));
- if (name == NULL)
- return FALSE;
-
- if (! CONST_STRNEQ (name, ".rela")
- || strcmp (bfd_get_section_name (abfd, sec),
- name + 5) != 0)
- {
- (*_bfd_error_handler)
- (_("%B: bad relocation section name `%s\'"),
- abfd, name);
- }
-
if (htab->elf.dynobj == NULL)
htab->elf.dynobj = abfd;
- dynobj = htab->elf.dynobj;
+ sreloc = _bfd_elf_make_dynamic_reloc_section
+ (sec, htab->elf.dynobj, 3, abfd, /*rela?*/ TRUE);
- sreloc = bfd_get_section_by_name (dynobj, name);
if (sreloc == NULL)
- {
- flagword flags;
-
- flags = (SEC_HAS_CONTENTS | SEC_READONLY
- | SEC_IN_MEMORY | SEC_LINKER_CREATED);
- if ((sec->flags & SEC_ALLOC) != 0)
- flags |= SEC_ALLOC | SEC_LOAD;
- sreloc = bfd_make_section_with_flags (dynobj,
- name,
- flags);
- if (sreloc == NULL
- || ! bfd_set_section_alignment (dynobj, sreloc, 3))
- return FALSE;
- }
- elf_section_data (sec)->sreloc = sreloc;
+ return FALSE;
+
+ /* Create the ifunc section, even if we will not encounter an
+ indirect function symbol. We may not even see one in the input
+ object file, but we can still encounter them in libraries. */
+ (void) _bfd_elf_make_ifunc_reloc_section
+ (abfd, sec, htab->elf.dynobj, 2);
}
/* If this is a global symbol, we count the number of
if (p == NULL || p->sec != sec)
{
bfd_size_type amt = sizeof *p;
+
p = ((struct elf64_x86_64_dyn_relocs *)
bfd_alloc (htab->elf.dynobj, amt));
if (p == NULL)
}
p->count += 1;
- if (r_type == R_X86_64_PC8
- || r_type == R_X86_64_PC16
- || r_type == R_X86_64_PC32
- || r_type == R_X86_64_PC64)
+ if (IS_X86_64_PCREL_TYPE (r_type))
p->pc_count += 1;
}
break;
elf_section_data (sec)->local_dynrel = NULL;
- symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
+ symtab_hdr = &elf_symtab_hdr (abfd);
sym_hashes = elf_sym_hashes (abfd);
local_got_refcounts = elf_local_got_refcounts (abfd);
struct elf64_x86_64_link_hash_table *htab;
struct elf64_x86_64_link_hash_entry *eh;
struct elf64_x86_64_dyn_relocs *p;
+ bfd_boolean use_indirect_section = FALSE;
if (h->root.type == bfd_link_hash_indirect)
return TRUE;
&& !info->shared
&& h->dynindx == -1
&& elf64_x86_64_hash_entry (h)->tls_type == GOT_TLS_IE)
- h->got.offset = (bfd_vma) -1;
+ {
+ h->got.offset = (bfd_vma) -1;
+ }
else if (h->got.refcount > 0)
{
asection *s;
/* Make sure undefined weak symbols are output as a dynamic
symbol in PIEs. */
else if (h->dynindx == -1
- && !h->forced_local)
- {
- if (! bfd_elf_link_record_dynamic_symbol (info, h))
- return FALSE;
- }
+ && ! h->forced_local
+ && ! bfd_elf_link_record_dynamic_symbol (info, h))
+ return FALSE;
}
}
+ else if (is_indirect_symbol (info->output_bfd, h)
+ && h->dynindx == -1
+ && ! h->forced_local)
+ {
+ if (bfd_elf_link_record_dynamic_symbol (info, h)
+ && h->dynindx != -1)
+ use_indirect_section = TRUE;
+ else
+ return FALSE;
+ }
else if (ELIMINATE_COPY_RELOCS)
{
/* For the non-shared case, discard space for relocs against
/* Make sure this symbol is output as a dynamic symbol.
Undefined weak syms won't yet be marked as dynamic. */
if (h->dynindx == -1
- && !h->forced_local)
- {
- if (! bfd_elf_link_record_dynamic_symbol (info, h))
- return FALSE;
- }
+ && ! h->forced_local
+ && ! bfd_elf_link_record_dynamic_symbol (info, h))
+ return FALSE;
/* If that succeeded, we know we'll be keeping all the
relocs. */
/* Finally, allocate space. */
for (p = eh->dyn_relocs; p != NULL; p = p->next)
{
- asection *sreloc = elf_section_data (p->sec)->sreloc;
+ asection * sreloc;
+
+ if (use_indirect_section)
+ sreloc = elf_section_data (p->sec)->indirect_relocs;
+ else
+ sreloc = elf_section_data (p->sec)->sreloc;
+
+ BFD_ASSERT (sreloc != NULL);
+
sreloc->size += p->count * sizeof (Elf64_External_Rela);
}
Elf_Internal_Shdr *symtab_hdr;
asection *srel;
- if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour)
+ if (! is_x86_64_elf (ibfd))
continue;
for (s = ibfd->sections; s != NULL; s = s->next)
srel->size += p->count * sizeof (Elf64_External_Rela);
if ((p->sec->output_section->flags & SEC_READONLY) != 0)
info->flags |= DF_TEXTREL;
-
}
}
}
if (!local_got)
continue;
- symtab_hdr = &elf_tdata (ibfd)->symtab_hdr;
+ symtab_hdr = &elf_symtab_hdr (ibfd);
locsymcount = symtab_hdr->sh_info;
end_local_got = local_got + locsymcount;
local_tls_type = elf64_x86_64_local_got_tls_type (ibfd);
/* Allocate global sym .plt and .got entries, and space for global
sym dynamic relocs. */
- elf_link_hash_traverse (&htab->elf, allocate_dynrelocs, (PTR) info);
+ elf_link_hash_traverse (&htab->elf, allocate_dynrelocs, info);
/* For every jump slot reserved in the sgotplt, reloc_count is
incremented. However, when we reserve space for TLS descriptors,
/* If any dynamic relocs apply to a read-only section,
then we need a DT_TEXTREL entry. */
if ((info->flags & DF_TEXTREL) == 0)
- elf_link_hash_traverse (&htab->elf, readonly_dynrelocs,
- (PTR) info);
+ elf_link_hash_traverse (&htab->elf, readonly_dynrelocs, info);
if ((info->flags & DF_TEXTREL) != 0)
{
tls_sec, 0, NULL, FALSE,
bed->collect, &bh)))
return FALSE;
+
+ elf64_x86_64_hash_table (info)->tls_module_base = bh;
+
tlsbase = (struct elf_link_hash_entry *)bh;
tlsbase->def_regular = 1;
tlsbase->other = STV_HIDDEN;
return TRUE;
}
+/* _TLS_MODULE_BASE_ needs to be treated especially when linking
+ executables. Rather than setting it to the beginning of the TLS
+ section, we have to set it to the end. This function may be called
+ multiple times, it is idempotent. */
+
+static void
+set_tls_module_base (struct bfd_link_info *info)
+{
+ struct bfd_link_hash_entry *base;
+
+ if (!info->executable)
+ return;
+
+ base = elf64_x86_64_hash_table (info)->tls_module_base;
+
+ if (!base)
+ return;
+
+ base->u.def.value = elf_hash_table (info)->tls_size;
+}
+
/* Return the base VMA address which should be subtracted from real addresses
when resolving @dtpoff relocation.
This is PT_TLS segment p_vaddr. */
Elf_Internal_Rela *rel;
Elf_Internal_Rela *relend;
+ BFD_ASSERT (is_x86_64_elf (input_bfd));
+
htab = elf64_x86_64_hash_table (info);
- symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
+ symtab_hdr = &elf_symtab_hdr (input_bfd);
sym_hashes = elf_sym_hashes (input_bfd);
local_got_offsets = elf_local_got_offsets (input_bfd);
local_tlsdesc_gotents = elf64_x86_64_local_tlsdesc_gotent (input_bfd);
+ set_tls_module_base (info);
+
rel = relocs;
relend = relocs + input_section->reloc_count;
for (; rel < relend; rel++)
case R_X86_64_PC16:
case R_X86_64_PC32:
if (info->shared
- && !SYMBOL_REFERENCES_LOCAL (info, h)
&& (input_section->flags & SEC_ALLOC) != 0
&& (input_section->flags & SEC_READONLY) != 0
- && (!h->def_regular
- || r_type != R_X86_64_PC32
- || h->type != STT_FUNC
- || ELF_ST_VISIBILITY (h->other) != STV_PROTECTED
- || !is_32bit_relative_branch (contents,
- rel->r_offset)))
+ && h != NULL)
{
- if (h->def_regular
- && r_type == R_X86_64_PC32
- && h->type == STT_FUNC
- && ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
- (*_bfd_error_handler)
- (_("%B: relocation R_X86_64_PC32 against protected function `%s' can not be used when making a shared object"),
- input_bfd, h->root.root.string);
+ bfd_boolean fail = FALSE;
+ bfd_boolean branch
+ = (r_type == R_X86_64_PC32
+ && is_32bit_relative_branch (contents, rel->r_offset));
+
+ if (SYMBOL_REFERENCES_LOCAL (info, h))
+ {
+ /* Symbol is referenced locally. Make sure it is
+ defined locally or for a branch. */
+ fail = !h->def_regular && !branch;
+ }
else
- (*_bfd_error_handler)
- (_("%B: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"),
- input_bfd, x86_64_elf_howto_table[r_type].name,
- h->root.root.string);
- bfd_set_error (bfd_error_bad_value);
- return FALSE;
+ {
+ /* Symbol isn't referenced locally. We only allow
+ branch to symbol with non-default visibility. */
+ fail = (!branch
+ || ELF_ST_VISIBILITY (h->other) == STV_DEFAULT);
+ }
+
+ if (fail)
+ {
+ const char *fmt;
+ const char *v;
+ const char *pic = "";
+
+ switch (ELF_ST_VISIBILITY (h->other))
+ {
+ case STV_HIDDEN:
+ v = _("hidden symbol");
+ break;
+ case STV_INTERNAL:
+ v = _("internal symbol");
+ break;
+ case STV_PROTECTED:
+ v = _("protected symbol");
+ break;
+ default:
+ v = _("symbol");
+ pic = _("; recompile with -fPIC");
+ break;
+ }
+
+ if (h->def_regular)
+ fmt = _("%B: relocation %s against %s `%s' can not be used when making a shared object%s");
+ else
+ fmt = _("%B: relocation %s against undefined %s `%s' can not be used when making a shared object%s");
+
+ (*_bfd_error_handler) (fmt, input_bfd,
+ x86_64_elf_howto_table[r_type].name,
+ v, h->root.root.string, pic);
+ bfd_set_error (bfd_error_bad_value);
+ return FALSE;
+ }
}
/* Fall through. */
&& (h == NULL
|| ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
|| h->root.type != bfd_link_hash_undefweak)
- && ((r_type != R_X86_64_PC8
- && r_type != R_X86_64_PC16
- && r_type != R_X86_64_PC32
- && r_type != R_X86_64_PC64)
- || !SYMBOL_CALLS_LOCAL (info, h)))
+ && (! IS_X86_64_PCREL_TYPE (r_type)
+ || ! SYMBOL_CALLS_LOCAL (info, h)))
+ || (! info->shared
+ && h != NULL
+ && h->dynindx != -1
+ && ! h->forced_local
+ && ((struct elf64_x86_64_link_hash_entry *) h)->dyn_relocs != NULL
+ && is_indirect_symbol (output_bfd, h))
|| (ELIMINATE_COPY_RELOCS
&& !info->shared
&& h != NULL
become local. */
else if (h != NULL
&& h->dynindx != -1
- && (r_type == R_X86_64_PC8
- || r_type == R_X86_64_PC16
- || r_type == R_X86_64_PC32
- || r_type == R_X86_64_PC64
- || !info->shared
- || !SYMBOLIC_BIND (info, h)
- || !h->def_regular))
+ && (IS_X86_64_PCREL_TYPE (r_type)
+ || ! info->shared
+ || ! SYMBOLIC_BIND (info, h)
+ || ! h->def_regular))
{
outrel.r_info = ELF64_R_INFO (h->dynindx, r_type);
outrel.r_addend = rel->r_addend;
}
}
- sreloc = elf_section_data (input_section)->sreloc;
- if (sreloc == NULL)
- abort ();
+ if (! info->shared
+ && h != NULL
+ && h->dynindx != -1
+ && ! h->forced_local
+ && is_indirect_symbol (output_bfd, h)
+ && elf_section_data (input_section)->indirect_relocs != NULL
+ && elf_section_data (input_section)->indirect_relocs->contents != NULL)
+ sreloc = elf_section_data (input_section)->indirect_relocs;
+ else
+ sreloc = elf_section_data (input_section)->sreloc;
+
+ BFD_ASSERT (sreloc != NULL && sreloc->contents != NULL);
loc = sreloc->contents;
loc += sreloc->reloc_count++ * sizeof (Elf64_External_Rela);
if (info->shared
&& SYMBOL_REFERENCES_LOCAL (info, h))
{
+ if (!h->def_regular)
+ return FALSE;
BFD_ASSERT((h->got.offset & 1) != 0);
rela.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE);
rela.r_addend = (h->root.u.def.value
static bfd_boolean
elf64_x86_64_add_symbol_hook (bfd *abfd,
- struct bfd_link_info *info ATTRIBUTE_UNUSED,
+ struct bfd_link_info *info,
Elf_Internal_Sym *sym,
const char **namep ATTRIBUTE_UNUSED,
flagword *flagsp ATTRIBUTE_UNUSED,
- asection **secp, bfd_vma *valp)
+ asection **secp,
+ bfd_vma *valp)
{
asection *lcomm;
*valp = sym->st_size;
break;
}
+
+ if (ELF_ST_TYPE (sym->st_info) == STT_GNU_IFUNC)
+ elf_tdata (info->output_bfd)->has_ifunc_symbols = TRUE;
+
return TRUE;
}
#define elf_backend_hash_symbol \
elf64_x86_64_hash_symbol
+#undef elf_backend_post_process_headers
+#define elf_backend_post_process_headers _bfd_elf_set_osabi
+
#include "elf64-target.h"
/* FreeBSD support. */
#undef ELF_OSABI
#define ELF_OSABI ELFOSABI_FREEBSD
-#undef elf_backend_post_process_headers
-#define elf_backend_post_process_headers _bfd_elf_set_osabi
-
#undef elf64_bed
#define elf64_bed elf64_x86_64_fbsd_bed