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Diffstat (limited to 'binutils-2.24/bfd/elf-ifunc.c')
-rw-r--r--binutils-2.24/bfd/elf-ifunc.c276
1 files changed, 0 insertions, 276 deletions
diff --git a/binutils-2.24/bfd/elf-ifunc.c b/binutils-2.24/bfd/elf-ifunc.c
deleted file mode 100644
index 8d48e66e..00000000
--- a/binutils-2.24/bfd/elf-ifunc.c
+++ /dev/null
@@ -1,276 +0,0 @@
-/* ELF STT_GNU_IFUNC support.
- Copyright 2009-2013
- Free Software Foundation, Inc.
-
- This file is part of BFD, the Binary File Descriptor library.
-
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 3 of the License, or
- (at your option) any later version.
-
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
- MA 02110-1301, USA. */
-
-#include "sysdep.h"
-#include "bfd.h"
-#include "bfdlink.h"
-#include "libbfd.h"
-#define ARCH_SIZE 0
-#include "elf-bfd.h"
-#include "safe-ctype.h"
-#include "libiberty.h"
-#include "objalloc.h"
-
-/* Create sections needed by STT_GNU_IFUNC symbol. */
-
-bfd_boolean
-_bfd_elf_create_ifunc_sections (bfd *abfd, struct bfd_link_info *info)
-{
- flagword flags, pltflags;
- asection *s;
- const struct elf_backend_data *bed = get_elf_backend_data (abfd);
- struct elf_link_hash_table *htab = elf_hash_table (info);
-
- if (htab->irelifunc != NULL || htab->iplt != NULL)
- return TRUE;
-
- flags = bed->dynamic_sec_flags;
- pltflags = flags;
- if (bed->plt_not_loaded)
- /* We do not clear SEC_ALLOC here because we still want the OS to
- allocate space for the section; it's just that there's nothing
- to read in from the object file. */
- pltflags &= ~ (SEC_CODE | SEC_LOAD | SEC_HAS_CONTENTS);
- else
- pltflags |= SEC_ALLOC | SEC_CODE | SEC_LOAD;
- if (bed->plt_readonly)
- pltflags |= SEC_READONLY;
-
- if (info->shared)
- {
- /* We need to create .rel[a].ifunc for shared objects. */
- const char *rel_sec = (bed->rela_plts_and_copies_p
- ? ".rela.ifunc" : ".rel.ifunc");
-
- s = bfd_make_section_with_flags (abfd, rel_sec,
- flags | SEC_READONLY);
- if (s == NULL
- || ! bfd_set_section_alignment (abfd, s,
- bed->s->log_file_align))
- return FALSE;
- htab->irelifunc = s;
- }
- else
- {
- /* We need to create .iplt, .rel[a].iplt, .igot and .igot.plt
- for static executables. */
- s = bfd_make_section_with_flags (abfd, ".iplt", pltflags);
- if (s == NULL
- || ! bfd_set_section_alignment (abfd, s, bed->plt_alignment))
- return FALSE;
- htab->iplt = s;
-
- s = bfd_make_section_with_flags (abfd,
- (bed->rela_plts_and_copies_p
- ? ".rela.iplt" : ".rel.iplt"),
- flags | SEC_READONLY);
- if (s == NULL
- || ! bfd_set_section_alignment (abfd, s,
- bed->s->log_file_align))
- return FALSE;
- htab->irelplt = s;
-
- /* We don't need the .igot section if we have the .igot.plt
- section. */
- if (bed->want_got_plt)
- s = bfd_make_section_with_flags (abfd, ".igot.plt", flags);
- else
- s = bfd_make_section_with_flags (abfd, ".igot", flags);
- if (s == NULL
- || !bfd_set_section_alignment (abfd, s,
- bed->s->log_file_align))
- return FALSE;
- htab->igotplt = s;
- }
-
- return TRUE;
-}
-
-/* Allocate space in .plt, .got and associated reloc sections for
- dynamic relocs against a STT_GNU_IFUNC symbol definition. */
-
-bfd_boolean
-_bfd_elf_allocate_ifunc_dyn_relocs (struct bfd_link_info *info,
- struct elf_link_hash_entry *h,
- struct elf_dyn_relocs **head,
- unsigned int plt_entry_size,
- unsigned int plt_header_size,
- unsigned int got_entry_size)
-{
- asection *plt, *gotplt, *relplt;
- struct elf_dyn_relocs *p;
- unsigned int sizeof_reloc;
- const struct elf_backend_data *bed;
- struct elf_link_hash_table *htab;
-
- /* When a shared library references a STT_GNU_IFUNC symbol defined
- in executable, the address of the resolved function may be used.
- But in non-shared executable, the address of its .plt slot may
- be used. Pointer equality may not work correctly. PIE should
- be used if pointer equality is required here. */
- if (!info->shared
- && (h->dynindx != -1
- || info->export_dynamic)
- && h->pointer_equality_needed)
- {
- info->callbacks->einfo
- (_("%F%P: dynamic STT_GNU_IFUNC symbol `%s' with pointer "
- "equality in `%B' can not be used when making an "
- "executable; recompile with -fPIE and relink with -pie\n"),
- h->root.root.string,
- h->root.u.def.section->owner);
- bfd_set_error (bfd_error_bad_value);
- return FALSE;
- }
-
- htab = elf_hash_table (info);
-
- /* When building shared library, we need to handle the case where it is
- marked with regular reference, but not non-GOT reference since the
- non-GOT reference bit may not be set here. */
- if (info->shared && !h->non_got_ref && h->ref_regular)
- for (p = *head; p != NULL; p = p->next)
- if (p->count)
- {
- h->non_got_ref = 1;
- goto keep;
- }
-
- /* Support garbage collection against STT_GNU_IFUNC symbols. */
- if (h->plt.refcount <= 0 && h->got.refcount <= 0)
- {
- h->got = htab->init_got_offset;
- h->plt = htab->init_plt_offset;
- *head = NULL;
- return TRUE;
- }
-
- /* Return and discard space for dynamic relocations against it if
- it is never referenced in a non-shared object. */
- if (!h->ref_regular)
- {
- if (h->plt.refcount > 0
- || h->got.refcount > 0)
- abort ();
- h->got = htab->init_got_offset;
- h->plt = htab->init_plt_offset;
- *head = NULL;
- return TRUE;
- }
-
-keep:
- bed = get_elf_backend_data (info->output_bfd);
- if (bed->rela_plts_and_copies_p)
- sizeof_reloc = bed->s->sizeof_rela;
- else
- sizeof_reloc = bed->s->sizeof_rel;
-
- /* When building a static executable, use .iplt, .igot.plt and
- .rel[a].iplt sections for STT_GNU_IFUNC symbols. */
- if (htab->splt != NULL)
- {
- plt = htab->splt;
- gotplt = htab->sgotplt;
- relplt = htab->srelplt;
-
- /* If this is the first .plt entry, make room for the special
- first entry. */
- if (plt->size == 0)
- plt->size += plt_header_size;
- }
- else
- {
- plt = htab->iplt;
- gotplt = htab->igotplt;
- relplt = htab->irelplt;
- }
-
- /* Don't update value of STT_GNU_IFUNC symbol to PLT. We need
- the original value for R_*_IRELATIVE. */
- h->plt.offset = plt->size;
-
- /* Make room for this entry in the .plt/.iplt section. */
- plt->size += plt_entry_size;
-
- /* We also need to make an entry in the .got.plt/.got.iplt section,
- which will be placed in the .got section by the linker script. */
- gotplt->size += got_entry_size;
-
- /* We also need to make an entry in the .rel[a].plt/.rel[a].iplt
- section. */
- relplt->size += sizeof_reloc;
- relplt->reloc_count++;
-
- /* We need dynamic relocation for STT_GNU_IFUNC symbol only when
- there is a non-GOT reference in a shared object. */
- if (!info->shared
- || !h->non_got_ref)
- *head = NULL;
-
- /* Finally, allocate space. */
- p = *head;
- if (p != NULL)
- {
- bfd_size_type count = 0;
- do
- {
- count += p->count;
- p = p->next;
- }
- while (p != NULL);
- htab->irelifunc->size += count * sizeof_reloc;
- }
-
- /* For STT_GNU_IFUNC symbol, .got.plt has the real function address
- and .got has the PLT entry adddress. We will load the GOT entry
- with the PLT entry in finish_dynamic_symbol if it is used. For
- branch, it uses .got.plt. For symbol value,
- 1. Use .got.plt in a shared object if it is forced local or not
- dynamic.
- 2. Use .got.plt in a non-shared object if pointer equality isn't
- needed.
- 3. Use .got.plt in PIE.
- 4. Use .got.plt if .got isn't used.
- 5. Otherwise use .got so that it can be shared among different
- objects at run-time.
- We only need to relocate .got entry in shared object. */
- if (h->got.refcount <= 0
- || (info->shared
- && (h->dynindx == -1
- || h->forced_local))
- || (!info->shared
- && !h->pointer_equality_needed)
- || (info->executable && info->shared)
- || htab->sgot == NULL)
- {
- /* Use .got.plt. */
- h->got.offset = (bfd_vma) -1;
- }
- else
- {
- h->got.offset = htab->sgot->size;
- htab->sgot->size += got_entry_size;
- if (info->shared)
- htab->srelgot->size += sizeof_reloc;
- }
-
- return TRUE;
-}
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