unsigned int is_func:1;
unsigned int is_func_descriptor:1;
- /* Whether global opd sym has been adjusted or not.
- After ppc64_elf_edit_opd has run, this flag should be set for all
- globals defined in any opd section. */
+ /* Whether global opd/toc sym has been adjusted or not.
+ After ppc64_elf_edit_opd/ppc64_elf_edit_toc has run, this flag
+ should be set for all globals defined in any opd/toc section. */
unsigned int adjust_done:1;
/* Set if we twiddled this symbol to weak at some stage. */
return TRUE;
}
+/* Called via elf_link_hash_traverse from ppc64_elf_edit_toc to adjust
+ the values of any global symbols in a toc section that has been
+ edited. Globals in toc sections should be a rarity, so this function
+ sets a flag if any are found in toc sections other than the one just
+ edited, so that futher hash table traversals can be avoided. */
+
+struct adjust_toc_info
+{
+ asection *toc;
+ unsigned long *skip;
+ bfd_boolean global_toc_syms;
+};
+
+static bfd_boolean
+adjust_toc_syms (struct elf_link_hash_entry *h, void *inf)
+{
+ struct ppc_link_hash_entry *eh;
+ struct adjust_toc_info *toc_inf = (struct adjust_toc_info *) inf;
+
+ if (h->root.type == bfd_link_hash_indirect)
+ return TRUE;
+
+ if (h->root.type == bfd_link_hash_warning)
+ h = (struct elf_link_hash_entry *) h->root.u.i.link;
+
+ if (h->root.type != bfd_link_hash_defined
+ && h->root.type != bfd_link_hash_defweak)
+ return TRUE;
+
+ eh = (struct ppc_link_hash_entry *) h;
+ if (eh->adjust_done)
+ return TRUE;
+
+ if (eh->elf.root.u.def.section == toc_inf->toc)
+ {
+ unsigned long skip = toc_inf->skip[eh->elf.root.u.def.value >> 3];
+ if (skip != (unsigned long) -1)
+ eh->elf.root.u.def.value -= skip;
+ else
+ {
+ (*_bfd_error_handler)
+ (_("%s defined in removed toc entry"), eh->elf.root.root.string);
+ eh->elf.root.u.def.section = &bfd_abs_section;
+ eh->elf.root.u.def.value = 0;
+ }
+ eh->adjust_done = 1;
+ }
+ else if (strcmp (eh->elf.root.u.def.section->name, ".toc") == 0)
+ toc_inf->global_toc_syms = TRUE;
+
+ return TRUE;
+}
+
+/* Examine all relocs referencing .toc sections in order to remove
+ unused .toc entries. */
+
+bfd_boolean
+ppc64_elf_edit_toc (bfd *obfd ATTRIBUTE_UNUSED, struct bfd_link_info *info)
+{
+ bfd *ibfd;
+ struct adjust_toc_info toc_inf;
+
+ toc_inf.global_toc_syms = TRUE;
+ for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next)
+ {
+ asection *toc, *sec;
+ Elf_Internal_Shdr *symtab_hdr;
+ Elf_Internal_Sym *local_syms;
+ struct elf_link_hash_entry **sym_hashes;
+ Elf_Internal_Rela *relstart, *rel, *wrel;
+ unsigned long *skip, *drop;
+ unsigned char *used;
+ unsigned char *keep, last, some_unused;
+
+ toc = bfd_get_section_by_name (ibfd, ".toc");
+ if (toc == NULL
+ || toc->sec_info_type == ELF_INFO_TYPE_JUST_SYMS
+ || elf_discarded_section (toc))
+ continue;
+
+ local_syms = NULL;
+ symtab_hdr = &elf_tdata (ibfd)->symtab_hdr;
+ sym_hashes = elf_sym_hashes (ibfd);
+
+ /* Look at sections dropped from the final link. */
+ skip = NULL;
+ relstart = NULL;
+ for (sec = ibfd->sections; sec != NULL; sec = sec->next)
+ {
+ if (sec->reloc_count == 0
+ || !elf_discarded_section (sec)
+ || get_opd_info (sec)
+ || (sec->flags & SEC_ALLOC) == 0
+ || (sec->flags & SEC_DEBUGGING) != 0)
+ continue;
+
+ relstart = _bfd_elf_link_read_relocs (ibfd, sec, NULL, NULL, FALSE);
+ if (relstart == NULL)
+ goto error_ret;
+
+ /* Run through the relocs to see which toc entries might be
+ unused. */
+ for (rel = relstart; rel < relstart + sec->reloc_count; ++rel)
+ {
+ enum elf_ppc64_reloc_type r_type;
+ unsigned long r_symndx;
+ asection *sym_sec;
+ struct elf_link_hash_entry *h;
+ Elf_Internal_Sym *sym;
+ bfd_vma val;
+
+ r_type = ELF64_R_TYPE (rel->r_info);
+ switch (r_type)
+ {
+ default:
+ continue;
+
+ case R_PPC64_TOC16:
+ case R_PPC64_TOC16_LO:
+ case R_PPC64_TOC16_HI:
+ case R_PPC64_TOC16_HA:
+ case R_PPC64_TOC16_DS:
+ case R_PPC64_TOC16_LO_DS:
+ break;
+ }
+
+ r_symndx = ELF64_R_SYM (rel->r_info);
+ if (!get_sym_h (&h, &sym, &sym_sec, NULL, &local_syms,
+ r_symndx, ibfd))
+ goto error_ret;
+
+ if (sym_sec != toc)
+ continue;
+
+ if (h != NULL)
+ val = h->root.u.def.value;
+ else
+ val = sym->st_value;
+ val += rel->r_addend;
+
+ if (val >= toc->size)
+ continue;
+
+ /* Anything in the toc ought to be aligned to 8 bytes.
+ If not, don't mark as unused. */
+ if (val & 7)
+ continue;
+
+ if (skip == NULL)
+ {
+ skip = bfd_zmalloc (sizeof (*skip) * (toc->size + 7) / 8);
+ if (skip == NULL)
+ goto error_ret;
+ }
+
+ skip[val >> 3] = 1;
+ }
+
+ if (elf_section_data (sec)->relocs != relstart)
+ free (relstart);
+ }
+
+ if (skip == NULL)
+ continue;
+
+ used = bfd_zmalloc (sizeof (*used) * (toc->size + 7) / 8);
+ if (used == NULL)
+ {
+ error_ret:
+ if (local_syms != NULL
+ && symtab_hdr->contents != (unsigned char *) local_syms)
+ free (local_syms);
+ if (sec != NULL
+ && relstart != NULL
+ && elf_section_data (sec)->relocs != relstart)
+ free (relstart);
+ if (skip != NULL)
+ free (skip);
+ return FALSE;
+ }
+
+ /* Now check all kept sections that might reference the toc. */
+ for (sec = ibfd->sections;
+ sec != NULL;
+ /* Check the toc itself last. */
+ sec = (sec == toc ? NULL
+ : sec->next == toc && sec->next->next ? sec->next->next
+ : sec->next == NULL ? toc
+ : sec->next))
+ {
+ int repeat;
+
+ if (sec->reloc_count == 0
+ || elf_discarded_section (sec)
+ || get_opd_info (sec)
+ || (sec->flags & SEC_ALLOC) == 0
+ || (sec->flags & SEC_DEBUGGING) != 0)
+ continue;
+
+ relstart = _bfd_elf_link_read_relocs (ibfd, sec, NULL, NULL, TRUE);
+ if (relstart == NULL)
+ goto error_ret;
+
+ /* Mark toc entries referenced as used. */
+ repeat = 0;
+ do
+ for (rel = relstart; rel < relstart + sec->reloc_count; ++rel)
+ {
+ enum elf_ppc64_reloc_type r_type;
+ unsigned long r_symndx;
+ asection *sym_sec;
+ struct elf_link_hash_entry *h;
+ Elf_Internal_Sym *sym;
+ bfd_vma val;
+
+ r_type = ELF64_R_TYPE (rel->r_info);
+ switch (r_type)
+ {
+ case R_PPC64_TOC16:
+ case R_PPC64_TOC16_LO:
+ case R_PPC64_TOC16_HI:
+ case R_PPC64_TOC16_HA:
+ case R_PPC64_TOC16_DS:
+ case R_PPC64_TOC16_LO_DS:
+ /* In case we're taking addresses of toc entries. */
+ case R_PPC64_ADDR64:
+ break;
+
+ default:
+ continue;
+ }
+
+ r_symndx = ELF64_R_SYM (rel->r_info);
+ if (!get_sym_h (&h, &sym, &sym_sec, NULL, &local_syms,
+ r_symndx, ibfd))
+ {
+ free (used);
+ goto error_ret;
+ }
+
+ if (sym_sec != toc)
+ continue;
+
+ if (h != NULL)
+ val = h->root.u.def.value;
+ else
+ val = sym->st_value;
+ val += rel->r_addend;
+
+ if (val >= toc->size)
+ continue;
+
+ /* For the toc section, we only mark as used if
+ this entry itself isn't unused. */
+ if (sec == toc
+ && !used[val >> 3]
+ && (used[rel->r_offset >> 3]
+ || !skip[rel->r_offset >> 3]))
+ /* Do all the relocs again, to catch reference
+ chains. */
+ repeat = 1;
+
+ used[val >> 3] = 1;
+ }
+ while (repeat);
+ }
+
+ /* Merge the used and skip arrays. Assume that TOC
+ doublewords not appearing as either used or unused belong
+ to to an entry more than one doubleword in size. */
+ for (drop = skip, keep = used, last = 0, some_unused = 0;
+ drop < skip + (toc->size + 7) / 8;
+ ++drop, ++keep)
+ {
+ if (*keep)
+ {
+ *drop = 0;
+ last = 0;
+ }
+ else if (*drop)
+ {
+ some_unused = 1;
+ last = 1;
+ }
+ else
+ *drop = last;
+ }
+
+ free (used);
+
+ if (some_unused)
+ {
+ bfd_byte *contents, *src;
+ unsigned long off;
+
+ /* Shuffle the toc contents, and at the same time convert the
+ skip array from booleans into offsets. */
+ if (!bfd_malloc_and_get_section (ibfd, toc, &contents))
+ goto error_ret;
+
+ elf_section_data (toc)->this_hdr.contents = contents;
+
+ for (src = contents, off = 0, drop = skip;
+ src < contents + toc->size;
+ src += 8, ++drop)
+ {
+ if (*drop)
+ {
+ *drop = (unsigned long) -1;
+ off += 8;
+ }
+ else if (off != 0)
+ {
+ *drop = off;
+ memcpy (src - off, src, 8);
+ }
+ }
+ toc->rawsize = toc->size;
+ toc->size = src - contents - off;
+
+ /* Read toc relocs. */
+ relstart = _bfd_elf_link_read_relocs (ibfd, toc, NULL, NULL, TRUE);
+ if (relstart == NULL)
+ goto error_ret;
+
+ /* Remove unused toc relocs, and adjust those we keep. */
+ wrel = relstart;
+ for (rel = relstart; rel < relstart + toc->reloc_count; ++rel)
+ if (skip[rel->r_offset >> 3] != (unsigned long) -1)
+ {
+ wrel->r_offset = rel->r_offset - skip[rel->r_offset >> 3];
+ wrel->r_info = rel->r_info;
+ wrel->r_addend = rel->r_addend;
+ ++wrel;
+ }
+ toc->reloc_count = wrel - relstart;
+
+ /* Adjust addends for relocs against the toc section sym. */
+ for (sec = ibfd->sections; sec != NULL; sec = sec->next)
+ {
+ if (sec->reloc_count == 0
+ || elf_discarded_section (sec))
+ continue;
+
+ relstart = _bfd_elf_link_read_relocs (ibfd, sec, NULL, NULL,
+ TRUE);
+ if (relstart == NULL)
+ goto error_ret;
+
+ for (rel = relstart; rel < relstart + sec->reloc_count; ++rel)
+ {
+ enum elf_ppc64_reloc_type r_type;
+ unsigned long r_symndx;
+ asection *sym_sec;
+ struct elf_link_hash_entry *h;
+ Elf_Internal_Sym *sym;
+
+ r_type = ELF64_R_TYPE (rel->r_info);
+ switch (r_type)
+ {
+ default:
+ continue;
+
+ case R_PPC64_TOC16:
+ case R_PPC64_TOC16_LO:
+ case R_PPC64_TOC16_HI:
+ case R_PPC64_TOC16_HA:
+ case R_PPC64_TOC16_DS:
+ case R_PPC64_TOC16_LO_DS:
+ case R_PPC64_ADDR64:
+ break;
+ }
+
+ r_symndx = ELF64_R_SYM (rel->r_info);
+ if (!get_sym_h (&h, &sym, &sym_sec, NULL, &local_syms,
+ r_symndx, ibfd))
+ goto error_ret;
+
+ if (sym_sec != toc || h != NULL || sym->st_value != 0)
+ continue;
+
+ rel->r_addend -= skip[rel->r_addend >> 3];
+ }
+ }
+
+ /* We shouldn't have local or global symbols defined in the TOC,
+ but handle them anyway. */
+ if (local_syms != NULL)
+ {
+ Elf_Internal_Sym *sym;
+
+ for (sym = local_syms;
+ sym < local_syms + symtab_hdr->sh_info;
+ ++sym)
+ if (sym->st_shndx != SHN_UNDEF
+ && (sym->st_shndx < SHN_LORESERVE
+ || sym->st_shndx > SHN_HIRESERVE)
+ && sym->st_value != 0
+ && bfd_section_from_elf_index (ibfd, sym->st_shndx) == toc)
+ {
+ if (skip[sym->st_value >> 3] != (unsigned long) -1)
+ sym->st_value -= skip[sym->st_value >> 3];
+ else
+ {
+ (*_bfd_error_handler)
+ (_("%s defined in removed toc entry"),
+ bfd_elf_local_sym_name (ibfd, sym));
+ sym->st_value = 0;
+ sym->st_shndx = SHN_ABS;
+ }
+ symtab_hdr->contents = (unsigned char *) local_syms;
+ }
+ }
+
+ /* Finally, adjust any global syms defined in the toc. */
+ if (toc_inf.global_toc_syms)
+ {
+ toc_inf.toc = toc;
+ toc_inf.skip = skip;
+ toc_inf.global_toc_syms = FALSE;
+ elf_link_hash_traverse (elf_hash_table (info), adjust_toc_syms,
+ &toc_inf);
+ }
+ }
+
+ if (local_syms != NULL
+ && symtab_hdr->contents != (unsigned char *) local_syms)
+ {
+ if (!info->keep_memory)
+ free (local_syms);
+ else
+ symtab_hdr->contents = (unsigned char *) local_syms;
+ }
+ free (skip);
+ }
+
+ return TRUE;
+}
+
/* Allocate space in .plt, .got and associated reloc sections for
dynamic relocs. */
static int dotsyms = 1;
/* Whether to run tls optimization. */
-static int notlsopt = 0;
+static int no_tls_opt = 0;
+
+/* Whether to run opd optimization. */
+static int no_opd_opt = 0;
+
+/* Whether to run toc optimization. */
+static int no_toc_opt = 0;
/* Whether to emit symbols for stubs. */
static int emit_stub_syms = 0;
{
if (stub_file != NULL)
{
- if (!ppc64_elf_edit_opd (output_bfd, &link_info, non_overlapping_opd))
+ if (!no_opd_opt
+ && !ppc64_elf_edit_opd (output_bfd, &link_info, non_overlapping_opd))
{
- einfo ("%X%P: can not edit opd %E\n");
+ einfo ("%X%P: can not edit %s %E\n", "opd");
return;
}
- if (ppc64_elf_tls_setup (output_bfd, &link_info) && !notlsopt)
+ if (ppc64_elf_tls_setup (output_bfd, &link_info) && !no_tls_opt)
{
/* Size the sections. This is premature, but we want to know the
TLS segment layout so that certain optimizations can be done. */
elf_tdata (output_bfd)->program_header_size = 0;
lang_reset_memory_regions ();
}
+
+ if (!no_toc_opt
+ && !link_info.relocatable
+ && !ppc64_elf_edit_toc (output_bfd, &link_info))
+ {
+ einfo ("%X%P: can not edit %s %E\n", "toc");
+ return;
+ }
}
gld${EMULATION_NAME}_before_allocation ();
#define OPTION_DOTSYMS (OPTION_STUBSYMS + 1)
#define OPTION_NO_DOTSYMS (OPTION_DOTSYMS + 1)
#define OPTION_NO_TLS_OPT (OPTION_NO_DOTSYMS + 1)
-#define OPTION_NON_OVERLAPPING_OPD (OPTION_NO_TLS_OPT + 1)
+#define OPTION_NO_OPD_OPT (OPTION_NO_TLS_OPT + 1)
+#define OPTION_NO_TOC_OPT (OPTION_NO_OPD_OPT + 1)
+#define OPTION_NON_OVERLAPPING_OPD (OPTION_NO_TOC_OPT + 1)
'
PARSE_AND_LIST_LONGOPTS='
{ "dotsyms", no_argument, NULL, OPTION_DOTSYMS },
{ "no-dotsyms", no_argument, NULL, OPTION_NO_DOTSYMS },
{ "no-tls-optimize", no_argument, NULL, OPTION_NO_TLS_OPT },
+ { "no-opd-optimize", no_argument, NULL, OPTION_NO_OPD_OPT },
+ { "no-toc-optimize", no_argument, NULL, OPTION_NO_TOC_OPT },
{ "non-overlapping-opd", no_argument, NULL, OPTION_NON_OVERLAPPING_OPD },
'
--no-tls-optimize Don'\''t try to optimize TLS accesses.\n"
));
fprintf (file, _("\
+ --no-opd-optimize Don'\''t optimize the OPD section.\n"
+ ));
+ fprintf (file, _("\
+ --no-toc-optimize Don'\''t optimize the TOC section.\n"
+ ));
+ fprintf (file, _("\
--non-overlapping-opd Canonicalize .opd, so that there are no overlapping\n\
.opd entries.\n"
));
break;
case OPTION_NO_TLS_OPT:
- notlsopt = 1;
+ no_tls_opt = 1;
+ break;
+
+ case OPTION_NO_OPD_OPT:
+ no_opd_opt = 1;
+ break;
+
+ case OPTION_NO_TOC_OPT:
+ no_toc_opt = 1;
break;
case OPTION_NON_OVERLAPPING_OPD:
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