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[PATCH] Optimize .eh_frame sections in ld, create PT_GNU_EH_FRAME ELF segment (take 2)
Hi!
On Thu, Dec 13, 2001 at 12:50:36AM +1030, Alan Modra wrote:
> Needs parentheses around elf_section_data .. _TYPE_MERGE so that emacs
> automatic formatting won't destroy your nice indentation. You do the
> same in many other places too.
...
> Protect with "do .. while (0)" would be nicer.
...
> Typo
The following patch has been updated to incorporate Alan's comments plus one
bug fix (eh_frame_ptr (DW_EH_PE_pcrel encoding) was using start of
.eh_frame_hdr as base, not the address of the eh_frame_ptr field, so it was
4 bytes off.
Ok to commit?
2001-12-12 Jakub Jelinek <jakub@redhat.com>
* elf-bfd.h (enum elf_link_info_type): New.
(struct bfd_elf_section_data): Remove stab_info and merge_info
fields, add sec_info and sec_info_type.
(struct elf_obj_tdata): Add eh_frame_hdr field.
(_bfd_elf_discard_section_eh_frame): New prototype.
(_bfd_elf_discard_section_eh_frame_hdr): Likewise.
(_bfd_elf_eh_frame_section_offset): Likewise.
(_bfd_elf_write_section_eh_frame): Likewise.
(_bfd_elf_write_section_eh_frame_hdr): Likewise.
* Makefile.am (BFD32_BACKENDS): Add elf-eh-frame.lo.
(BFD32_BACKENDS_CFILES): Add elf-eh-frame.c.
(elf-eh-frame.lo): New.
* Makefile.in: Rebuilt.
* configure.in (elf): Add elf-eh-frame.lo.
* configure: Rebuilt.
* elf.c (_bfd_elf_print_private_bfd_data): Support PT_GNU_EH_FRAME.
(map_sections_to_segments): Create PT_GNU_EH_FRAME if requested.
(get_program_header_size): Take into account PT_GNU_EH_FRAME
segment.
(_bfd_elf_rela_local_sym): Use sec_info_type and sec_info.
(_bfd_elf_rel_local_sym): Likewise.
(_bfd_elf_section_offset): Likewise. Call
_bfd_elf_eh_frame_section_offset too.
* elfxx-ia64.c (elfNN_ia64_relocate_section): Use sec_info_type and
sec_info.
* elf64-alpha.c (elf64_alpha_relocate_section): Likewise.
* elf-eh-frame.c: New file.
* elflink.h (elf_link_add_object_symbols): Don't optimize SHF_MERGE
.stab sections. Set sec_info_type, use sec_info instead
of merge_info and stab_info.
(elf_link_create_dynamic_sections): Create .eh_frame_hdr section
if --eh-frame-hdr.
(elf_bfd_final_link): Write .eh_frame_hdr section.
(elf_link_sec_merge_syms): Use sec_info_type and sec_info.
(elf_link_input_bfd): Likewise.
Call _bfd_elf_write_section_eh_frame to write .eh_frame sections.
(elf_bfd_discard_info): Add output_bfd argument.
Call _bfd_elf_discard_section_eh_frame and
_bfd_elf_discard_section_eh_frame_hdr.
(elf_section_ignore_discarded_relocs): Use sec_info_type, not section
names.
* bfd-in.h (bfd_elf32_discard_info, bfd_elf64_discard_info): Adjust
prototypes.
* bfd-in2.h (bfd_elf32_discard_info, bfd_elf64_discard_info): Likewise.
* elf/common.h (PT_GNU_EH_FRAME): Define.
* bfdlink.h (struct bfd_link_info): Add eh_frame_hdr field.
* emultempl/elf32.em (finish): Supply output_bfd
to bfd_elf*_discard_info.
(OPTION_EH_FRAME_HDR): Define.
(longopts): Add --eh-frame-hdr.
(parse_args): Handle it.
(list_options): Add --eh-frame-hdr to help.
* emultempl/hppaelf.em (finish): Supply output_bfd
to bfd_elf*_discard_info.
* scripttempl/elf.sc (.eh_frame_hdr): Add.
* readelf.c (get_segment_type): Support PT_GNU_EH_FRAME.
--- binutils/readelf.c.jj Fri Dec 7 12:59:51 2001
+++ binutils/readelf.c Mon Dec 10 14:38:19 2001
@@ -1820,6 +1820,9 @@ get_segment_type (p_type)
case PT_SHLIB: return "SHLIB";
case PT_PHDR: return "PHDR";
+ case PT_GNU_EH_FRAME:
+ return "GNU_EH_FRAME";
+
default:
if ((p_type >= PT_LOPROC) && (p_type <= PT_HIPROC))
{
--- bfd/elf.c.jj Fri Dec 7 13:22:19 2001
+++ bfd/elf.c Mon Dec 10 15:18:40 2001
@@ -812,6 +812,7 @@ _bfd_elf_print_private_bfd_data (abfd, f
case PT_NOTE: pt = "NOTE"; break;
case PT_SHLIB: pt = "SHLIB"; break;
case PT_PHDR: pt = "PHDR"; break;
+ case PT_GNU_EH_FRAME: pt = "EH_FRAME"; break;
default: sprintf (buf, "0x%lx", p->p_type); pt = buf; break;
}
fprintf (f, "%8s off 0x", pt);
@@ -2794,7 +2795,7 @@ map_sections_to_segments (abfd)
asection **hdrpp;
boolean phdr_in_segment = true;
boolean writable;
- asection *dynsec;
+ asection *dynsec, *eh_frame_hdr;
bfd_size_type amt;
if (elf_tdata (abfd)->segment_map != NULL)
@@ -3034,6 +3035,24 @@ map_sections_to_segments (abfd)
}
}
+ /* If there is a .eh_frame_hdr section, throw in a PT_GNU_EH_FRAME
+ segment. */
+ eh_frame_hdr = bfd_get_section_by_name (abfd, ".eh_frame_hdr");
+ if (eh_frame_hdr != NULL && (eh_frame_hdr->flags & SEC_LOAD))
+ {
+ amt = sizeof (struct elf_segment_map);
+ m = (struct elf_segment_map *) bfd_zalloc (abfd, amt);
+ if (m == NULL)
+ goto error_return;
+ m->next = NULL;
+ m->p_type = PT_GNU_EH_FRAME;
+ m->count = 1;
+ m->sections[0] = eh_frame_hdr;
+
+ *pm = m;
+ pm = &m->next;
+ }
+
free (sections);
sections = NULL;
@@ -3550,6 +3569,13 @@ get_program_header_size (abfd)
++segs;
}
+ if (elf_tdata (abfd)->eh_frame_hdr
+ && bfd_get_section_by_name (abfd, ".eh_frame_hdr") != NULL)
+ {
+ /* We need a PT_GNU_EH_FRAME segment. */
+ ++segs;
+ }
+
for (s = abfd->sections; s != NULL; s = s->next)
{
if ((s->flags & SEC_LOAD) != 0
@@ -6394,14 +6420,14 @@ _bfd_elf_rela_local_sym (abfd, sym, sec,
+ sym->st_value);
if ((sec->flags & SEC_MERGE)
&& ELF_ST_TYPE (sym->st_info) == STT_SECTION
- && elf_section_data (sec)->merge_info)
+ && elf_section_data (sec)->sec_info_type == ELF_INFO_TYPE_MERGE)
{
asection *msec;
msec = sec;
rel->r_addend =
_bfd_merged_section_offset (abfd, &msec,
- elf_section_data (sec)->merge_info,
+ elf_section_data (sec)->sec_info,
sym->st_value + rel->r_addend,
(bfd_vma) 0)
- relocation;
@@ -6419,11 +6445,11 @@ _bfd_elf_rel_local_sym (abfd, sym, psec,
{
asection *sec = *psec;
- if (elf_section_data (sec)->merge_info == NULL)
+ if (elf_section_data (sec)->sec_info_type != ELF_INFO_TYPE_MERGE)
return sym->st_value + addend;
return _bfd_merged_section_offset (abfd, psec,
- elf_section_data (sec)->merge_info,
+ elf_section_data (sec)->sec_info,
sym->st_value + addend, (bfd_vma) 0);
}
@@ -6437,9 +6463,15 @@ _bfd_elf_section_offset (abfd, info, sec
struct bfd_elf_section_data *sec_data;
sec_data = elf_section_data (sec);
- if (sec_data->stab_info != NULL)
- return _bfd_stab_section_offset
- (abfd, &elf_hash_table (info)->stab_info,
- sec, &sec_data->stab_info, offset);
- return offset;
+ switch (sec_data->sec_info_type)
+ {
+ case ELF_INFO_TYPE_STABS:
+ return _bfd_stab_section_offset
+ (abfd, &elf_hash_table (info)->merge_info, sec, &sec_data->sec_info,
+ offset);
+ case ELF_INFO_TYPE_EH_FRAME:
+ return _bfd_elf_eh_frame_section_offset (abfd, sec, offset);
+ default:
+ return offset;
+ }
}
--- bfd/elfxx-ia64.c.jj Fri Dec 7 13:22:19 2001
+++ bfd/elfxx-ia64.c Wed Dec 12 20:04:22 2001
@@ -3489,7 +3489,8 @@ elfNN_ia64_relocate_section (output_bfd,
value = _bfd_elf_rela_local_sym (output_bfd, sym, sym_sec, rel);
if ((sym_sec->flags & SEC_MERGE)
&& ELF_ST_TYPE (sym->st_info) == STT_SECTION
- && elf_section_data (sym_sec)->merge_info)
+ && (elf_section_data (sym_sec)->sec_info_type
+ == ELF_INFO_TYPE_MERGE))
{
struct elfNN_ia64_local_hash_entry *loc_h;
@@ -3505,7 +3506,7 @@ elfNN_ia64_relocate_section (output_bfd,
dynent->addend =
_bfd_merged_section_offset (output_bfd, &msec,
elf_section_data (msec)->
- merge_info,
+ sec_info,
sym->st_value
+ dynent->addend,
(bfd_vma) 0);
--- bfd/elf64-alpha.c.jj Fri Dec 7 13:22:19 2001
+++ bfd/elf64-alpha.c Wed Dec 12 20:04:51 2001
@@ -3406,7 +3406,8 @@ elf64_alpha_relocate_section (output_bfd
unless it has been done already. */
if ((sec->flags & SEC_MERGE)
&& ELF_ST_TYPE (sym->st_info) == STT_SECTION
- && elf_section_data (sec)->merge_info
+ && (elf_section_data (sec)->sec_info_type
+ == ELF_INFO_TYPE_MERGE)
&& (gotent->flags & ALPHA_ELF_GOT_ENTRY_RELOCS_XLATED) == 0)
{
struct alpha_elf_got_entry *ent;
@@ -3421,7 +3422,7 @@ elf64_alpha_relocate_section (output_bfd
ent->addend =
_bfd_merged_section_offset (output_bfd, &msec,
elf_section_data (sec)->
- merge_info,
+ sec_info,
sym->st_value
+ ent->addend,
(bfd_vma) 0);
--- bfd/elf-eh-frame.c.jj Wed Dec 5 16:37:34 2001
+++ bfd/elf-eh-frame.c Wed Dec 12 20:12:34 2001
@@ -0,0 +1,1038 @@
+/* .eh_frame section optimization.
+ Copyright 2001 Free Software Foundation, Inc.
+ Written by Jakub Jelinek <jakub@redhat.com>.
+
+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 2 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
+
+#include "bfd.h"
+#include "sysdep.h"
+#include "libbfd.h"
+#include "elf-bfd.h"
+#include "elf/dwarf2.h"
+
+#define EH_FRAME_HDR_SIZE 8
+
+struct cie_header
+{
+ unsigned int length;
+ unsigned int id;
+};
+
+struct cie
+{
+ struct cie_header hdr;
+ unsigned char version;
+ unsigned char augmentation[20];
+ unsigned int code_align;
+ int data_align;
+ unsigned int ra_column;
+ unsigned int augmentation_size;
+ struct elf_link_hash_entry *personality;
+ unsigned char per_encoding;
+ unsigned char lsda_encoding;
+ unsigned char fde_encoding;
+ unsigned char initial_insn_length;
+ unsigned char make_relative;
+ unsigned char initial_instructions[50];
+};
+
+struct eh_cie_fde
+{
+ unsigned int offset;
+ unsigned int size;
+ asection *sec;
+ unsigned int new_offset;
+ unsigned char fde_encoding;
+ unsigned char cie : 1;
+ unsigned char removed : 1;
+ unsigned char make_relative : 1;
+};
+
+struct eh_frame_sec_info
+{
+ unsigned int count;
+ unsigned int alloced;
+ struct eh_cie_fde entry[1];
+};
+
+struct eh_frame_array_ent
+{
+ bfd_vma initial_loc;
+ bfd_vma fde;
+};
+
+struct eh_frame_hdr_info
+{
+ struct cie last_cie;
+ asection *last_cie_sec;
+ unsigned int last_cie_offset;
+ unsigned int fde_count, array_count;
+ struct eh_frame_array_ent *array;
+ /* TRUE if .eh_frame_hdr should contain the sorted search table.
+ We build it if we successfully read all .eh_frame input sections
+ and recognize them. */
+ boolean table;
+};
+
+static bfd_vma read_unsigned_leb128
+ PARAMS ((bfd *, char *, unsigned int *));
+static bfd_signed_vma read_signed_leb128
+ PARAMS ((bfd *, char *, unsigned int *));
+static int get_DW_EH_PE_width
+ PARAMS ((int, int));
+static int cie_compare
+ PARAMS ((struct cie *, struct cie *));
+static int vma_compare
+ PARAMS ((const PTR a, const PTR b));
+
+/* Helper function for reading uleb128 encoded data. */
+
+static bfd_vma
+read_unsigned_leb128 (abfd, buf, bytes_read_ptr)
+ bfd *abfd ATTRIBUTE_UNUSED;
+ char *buf;
+ unsigned int *bytes_read_ptr;
+{
+ bfd_vma result;
+ unsigned int num_read;
+ int shift;
+ unsigned char byte;
+
+ result = 0;
+ shift = 0;
+ num_read = 0;
+ do
+ {
+ byte = bfd_get_8 (abfd, (bfd_byte *) buf);
+ buf ++;
+ num_read ++;
+ result |= (((bfd_vma) byte & 0x7f) << shift);
+ shift += 7;
+ }
+ while (byte & 0x80);
+ * bytes_read_ptr = num_read;
+ return result;
+}
+
+/* Helper function for reading sleb128 encoded data. */
+
+static bfd_signed_vma
+read_signed_leb128 (abfd, buf, bytes_read_ptr)
+ bfd *abfd ATTRIBUTE_UNUSED;
+ char *buf;
+ unsigned int * bytes_read_ptr;
+{
+ bfd_vma result;
+ int shift;
+ int num_read;
+ unsigned char byte;
+
+ result = 0;
+ shift = 0;
+ num_read = 0;
+ do
+ {
+ byte = bfd_get_8 (abfd, (bfd_byte *) buf);
+ buf ++;
+ num_read ++;
+ result |= (((bfd_vma) byte & 0x7f) << shift);
+ shift += 7;
+ }
+ while (byte & 0x80);
+ if (byte & 0x40)
+ result |= (((bfd_vma) -1) << (shift - 7)) << 7;
+ * bytes_read_ptr = num_read;
+ return result;
+}
+
+#define read_uleb128(VAR, BUF) \
+do \
+ { \
+ (VAR) = read_unsigned_leb128 (abfd, buf, &leb128_tmp); \
+ (BUF) += leb128_tmp; \
+ } \
+while (0)
+
+#define read_sleb128(VAR, BUF) \
+do \
+ { \
+ (VAR) = read_signed_leb128 (abfd, buf, &leb128_tmp); \
+ (BUF) += leb128_tmp; \
+ } \
+while (0)
+
+/* Return 0 if either encoding is variable width, or not yet known to bfd. */
+
+static
+int get_DW_EH_PE_width (encoding, ptr_size)
+ int encoding, ptr_size;
+{
+ /* DW_EH_PE_ values of 0x60 and 0x70 weren't defined at the time .eh_frame
+ was added to bfd. */
+ if ((encoding & 0x60) == 0x60)
+ return 0;
+
+ switch (encoding & 7)
+ {
+ case DW_EH_PE_udata2: return 2;
+ case DW_EH_PE_udata4: return 4;
+ case DW_EH_PE_udata8: return 8;
+ case DW_EH_PE_absptr: return ptr_size;
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+/* Return zero if C1 and C2 CIEs can be merged. */
+
+static
+int cie_compare (c1, c2)
+ struct cie *c1, *c2;
+{
+ if (c1->hdr.length == c2->hdr.length
+ && c1->version == c2->version
+ && strcmp (c1->augmentation, c2->augmentation) == 0
+ && strcmp (c1->augmentation, "eh") != 0
+ && c1->code_align == c2->code_align
+ && c1->data_align == c2->data_align
+ && c1->ra_column == c2->ra_column
+ && c1->augmentation_size == c2->augmentation_size
+ && c1->personality == c2->personality
+ && c1->per_encoding == c2->per_encoding
+ && c1->lsda_encoding == c2->lsda_encoding
+ && c1->fde_encoding == c2->fde_encoding
+ && c1->initial_insn_length
+ == c2->initial_insn_length
+ && memcmp (c1->initial_instructions,
+ c2->initial_instructions,
+ c1->initial_insn_length) == 0)
+ return 0;
+
+ return 1;
+}
+
+/* This function is called for each input file before the .eh_frame
+ section is relocated. It discards duplicate CIEs and FDEs for discarded
+ functions. The function returns true iff any entries have been
+ deleted. */
+
+boolean
+_bfd_elf_discard_section_eh_frame (abfd, info, sec, ehdrsec,
+ reloc_symbol_deleted_p, cookie)
+ bfd *abfd;
+ struct bfd_link_info *info;
+ asection *sec, *ehdrsec;
+ boolean (*reloc_symbol_deleted_p) (bfd_vma, PTR);
+ struct elf_reloc_cookie *cookie;
+{
+ bfd_byte *ehbuf = NULL, *buf;
+ bfd_byte *last_cie, *last_fde;
+ struct cie_header hdr;
+ struct cie cie;
+ struct eh_frame_hdr_info *hdr_info;
+ struct eh_frame_sec_info *sec_info;
+ unsigned int leb128_tmp;
+ unsigned int cie_usage_count, last_cie_ndx, i, offset, make_relative;
+ Elf_Internal_Rela *rel;
+ bfd_size_type new_size;
+ unsigned int ptr_size;
+
+ if (sec->_raw_size == 0)
+ {
+ /* This file does not contain .eh_frame information. */
+ return false;
+ }
+
+ if ((sec->output_section != NULL
+ && bfd_is_abs_section (sec->output_section)))
+ {
+ /* At least one of the sections is being discarded from the
+ link, so we should just ignore them. */
+ return false;
+ }
+
+ /* Read the frame unwind information from abfd. */
+
+ ehbuf = (bfd_byte *) bfd_malloc (sec->_raw_size);
+ if (ehbuf == NULL
+ || ! bfd_get_section_contents (abfd, sec, ehbuf, (bfd_vma) 0,
+ sec->_raw_size))
+ {
+ if (elf_section_data (ehdrsec)->sec_info_type
+ != ELF_INFO_TYPE_EH_FRAME_HDR)
+ {
+ elf_section_data (ehdrsec)->sec_info
+ = bfd_zmalloc (sizeof (struct eh_frame_hdr_info));
+ elf_section_data (ehdrsec)->sec_info_type
+ = ELF_INFO_TYPE_EH_FRAME_HDR;
+ }
+ return false;
+ }
+
+ if (sec->_raw_size >= 4
+ && bfd_get_32 (abfd, ehbuf) == 0
+ && cookie->rel == cookie->relend)
+ {
+ /* Empty .eh_frame section. */
+ free (ehbuf);
+ return false;
+ }
+
+ if (elf_section_data (ehdrsec)->sec_info_type
+ != ELF_INFO_TYPE_EH_FRAME_HDR)
+ {
+ hdr_info = (struct eh_frame_hdr_info *)
+ bfd_zmalloc (sizeof (struct eh_frame_hdr_info));
+ hdr_info->table = true;
+ elf_section_data (ehdrsec)->sec_info = hdr_info;
+ elf_section_data (ehdrsec)->sec_info_type
+ = ELF_INFO_TYPE_EH_FRAME_HDR;
+ }
+ else
+ hdr_info = (struct eh_frame_hdr_info *)
+ elf_section_data (ehdrsec)->sec_info;
+
+ /* If .eh_frame section size doesn't fit into int, we cannot handle
+ it (it would need to use 64-bit .eh_frame format anyway). */
+ if (sec->_raw_size != (unsigned int) sec->_raw_size)
+ return false;
+
+ ptr_size = (elf_elfheader (abfd)->e_ident[EI_CLASS]
+ == ELFCLASS64) ? 8 : 4;
+ buf = ehbuf;
+ last_cie = NULL;
+ last_cie_ndx = 0;
+ memset (&cie, 0, sizeof (cie));
+ cie_usage_count = 0;
+ new_size = sec->_raw_size;
+ make_relative = hdr_info->last_cie.make_relative;
+ sec_info = bfd_zmalloc (sizeof (struct eh_frame_sec_info)
+ + 99 * sizeof (struct eh_cie_fde));
+ if (sec_info == NULL)
+ goto free_no_table;
+ sec_info->alloced = 100;
+
+#define ENSURE_NO_RELOCS(buf) \
+ if (cookie->rel < cookie->relend \
+ && cookie->rel->r_offset \
+ < (bfd_size_type) ((buf) - ehbuf)) \
+ goto free_no_table
+
+#define SKIP_RELOCS(buf) \
+ while (cookie->rel < cookie->relend \
+ && cookie->rel->r_offset \
+ < (bfd_size_type) ((buf) - ehbuf)) \
+ cookie->rel++
+
+#define GET_RELOC(buf) \
+ ((cookie->rel < cookie->relend \
+ && cookie->rel->r_offset \
+ == (bfd_size_type) ((buf) - ehbuf)) \
+ ? cookie->rel : NULL)
+
+ for (;;)
+ {
+ unsigned char *aug;
+
+ if (sec_info->count == sec_info->alloced)
+ {
+ sec_info = bfd_realloc (sec_info,
+ sizeof (struct eh_frame_sec_info)
+ + (sec_info->alloced + 99)
+ * sizeof (struct eh_cie_fde));
+ if (sec_info == NULL)
+ goto free_no_table;
+
+ memset (&sec_info->entry[sec_info->alloced], 0,
+ 100 * sizeof (struct eh_cie_fde));
+ sec_info->alloced += 100;
+ }
+
+ last_fde = buf;
+ /* If we are at the end of the section, we still need to decide
+ on whether to output or discard last encountered CIE (if any). */
+ if ((bfd_size_type) (buf - ehbuf) == sec->_raw_size)
+ hdr.id = (unsigned int) -1;
+ else
+ {
+ if ((bfd_size_type) (buf + 4 - ehbuf) > sec->_raw_size)
+ /* No space for CIE/FDE header length. */
+ goto free_no_table;
+
+ hdr.length = bfd_get_32 (abfd, buf);
+ if (hdr.length == 0xffffffff)
+ /* 64-bit .eh_frame is not supported. */
+ goto free_no_table;
+ buf += 4;
+ if ((buf - ehbuf) + hdr.length > sec->_raw_size)
+ /* CIE/FDE not contained fully in this .eh_frame input section. */
+ goto free_no_table;
+
+ sec_info->entry[sec_info->count].offset = last_fde - ehbuf;
+ sec_info->entry[sec_info->count].size = 4 + hdr.length;
+
+ if (hdr.length == 0)
+ {
+ /* CIE with length 0 must be only the last in the section. */
+ if ((bfd_size_type) (buf - ehbuf) < sec->_raw_size)
+ goto free_no_table;
+ ENSURE_NO_RELOCS (buf);
+ sec_info->count++;
+ /* Now just finish last encountered CIE processing and break
+ the loop. */
+ hdr.id = (unsigned int) -1;
+ }
+ else
+ {
+ hdr.id = bfd_get_32 (abfd, buf);
+ buf += 4;
+ if (hdr.id == (unsigned int) -1)
+ goto free_no_table;
+ }
+ }
+
+ if (hdr.id == 0 || hdr.id == (unsigned int) -1)
+ {
+ unsigned int initial_insn_length;
+
+ /* CIE */
+ if (last_cie != NULL)
+ {
+ /* Now check if this CIE is identical to last CIE, in which case
+ we can remove it, provided we adjust all FDEs.
+ Also, it can be removed if we have removed all FDEs using
+ that. */
+ if (cie_compare (&cie, &hdr_info->last_cie) == 0
+ || cie_usage_count == 0)
+ {
+ new_size -= cie.hdr.length + 4;
+ sec_info->entry[last_cie_ndx].removed = 1;
+ sec_info->entry[last_cie_ndx].sec = hdr_info->last_cie_sec;
+ sec_info->entry[last_cie_ndx].new_offset
+ = hdr_info->last_cie_offset;
+ }
+ else
+ {
+ hdr_info->last_cie = cie;
+ hdr_info->last_cie_sec = sec;
+ hdr_info->last_cie_offset = last_cie - ehbuf;
+ sec_info->entry[last_cie_ndx].make_relative
+ = cie.make_relative;
+ }
+ }
+
+ if (hdr.id == (unsigned int) -1)
+ break;
+
+ last_cie_ndx = sec_info->count;
+ sec_info->entry[sec_info->count].cie = 1;
+
+ cie_usage_count = 0;
+ memset (&cie, 0, sizeof (cie));
+ cie.hdr = hdr;
+ cie.version = *buf++;
+
+ /* Cannot handle unknown versions. */
+ if (cie.version != 1)
+ goto free_no_table;
+ if (strlen (buf) > sizeof (cie.augmentation) - 1)
+ goto free_no_table;
+
+ strcpy (cie.augmentation, buf);
+ buf = strchr (buf, '\0') + 1;
+ ENSURE_NO_RELOCS (buf);
+ if (buf[0] == 'e' && buf[1] == 'h')
+ {
+ /* GCC < 3.0 .eh_frame CIE */
+ /* We cannot merge "eh" CIEs because __EXCEPTION_TABLE__
+ is private to each CIE, so we don't need it for anything.
+ Just skip it. */
+ buf += ptr_size;
+ SKIP_RELOCS (buf);
+ }
+ read_uleb128 (cie.code_align, buf);
+ read_sleb128 (cie.data_align, buf);
+ read_uleb128 (cie.ra_column, buf);
+ ENSURE_NO_RELOCS (buf);
+ cie.lsda_encoding = DW_EH_PE_omit;
+ cie.fde_encoding = DW_EH_PE_omit;
+ cie.per_encoding = DW_EH_PE_omit;
+ aug = cie.augmentation;
+ if (aug[0] != 'e' || aug[1] != 'h')
+ {
+ if (*aug == 'z')
+ {
+ aug++;
+ read_uleb128 (cie.augmentation_size, buf);
+ ENSURE_NO_RELOCS (buf);
+ }
+
+ while (*aug != '\0')
+ switch (*aug++)
+ {
+ case 'L':
+ cie.lsda_encoding = *buf++;
+ ENSURE_NO_RELOCS (buf);
+ if (get_DW_EH_PE_width (cie.lsda_encoding, ptr_size) == 0)
+ goto free_no_table;
+ break;
+ case 'R':
+ cie.fde_encoding = *buf++;
+ ENSURE_NO_RELOCS (buf);
+ if (get_DW_EH_PE_width (cie.fde_encoding, ptr_size) == 0)
+ goto free_no_table;
+ break;
+ case 'P':
+ {
+ int per_width;
+
+ cie.per_encoding = *buf++;
+ per_width = get_DW_EH_PE_width (cie.per_encoding,
+ ptr_size);
+ if (per_width == 0)
+ goto free_no_table;
+ if ((cie.per_encoding & 0xf0) == DW_EH_PE_aligned)
+ buf = ehbuf
+ + ((buf - ehbuf + per_width - 1)
+ & ~((bfd_size_type) per_width - 1));
+ ENSURE_NO_RELOCS (buf);
+ rel = GET_RELOC (buf);
+ /* Ensure we have a reloc here, against
+ a global symbol. */
+ if (rel != NULL)
+ {
+ unsigned long r_symndx;
+
+#ifdef BFD64
+ if (ptr_size == 8)
+ r_symndx = ELF64_R_SYM (cookie->rel->r_info);
+ else
+#endif
+ r_symndx = ELF32_R_SYM (cookie->rel->r_info);
+ if (r_symndx >= cookie->locsymcount)
+ {
+ struct elf_link_hash_entry *h;
+
+ r_symndx -= cookie->extsymoff;
+ h = cookie->sym_hashes[r_symndx];
+
+ while (h->root.type == bfd_link_hash_indirect
+ || h->root.type == bfd_link_hash_warning)
+ h = (struct elf_link_hash_entry *)
+ h->root.u.i.link;
+
+ cie.personality = h;
+ }
+ cookie->rel++;
+ }
+ buf += per_width;
+ }
+ break;
+ default:
+ /* Unrecognized augmentation. Better bail out. */
+ goto free_no_table;
+ }
+ }
+
+ /* For shared libraries, try to get rid of as many RELATIVE relocs
+ as possible.
+ FIXME: For this to work, ELF backends need to perform the
+ relocation if omitting dynamic relocs, not skip it. */
+ if (0
+ && info->shared
+ && (cie.fde_encoding & 0xf0) == DW_EH_PE_absptr)
+ cie.make_relative = 1;
+
+ /* If FDE encoding was not specified, it defaults to
+ DW_EH_absptr. */
+ if (cie.fde_encoding == DW_EH_PE_omit)
+ cie.fde_encoding = DW_EH_PE_absptr;
+
+ initial_insn_length = cie.hdr.length - (buf - last_fde - 4);
+ if (initial_insn_length <= 50)
+ {
+ cie.initial_insn_length = initial_insn_length;
+ memcpy (cie.initial_instructions, buf, initial_insn_length);
+ }
+ buf += initial_insn_length;
+ ENSURE_NO_RELOCS (buf);
+ last_cie = last_fde;
+ }
+ else
+ {
+ /* Ensure this FDE uses the last CIE encountered. */
+ if (last_cie == NULL
+ || hdr.id != (unsigned int) (buf - 4 - last_cie))
+ goto free_no_table;
+
+ ENSURE_NO_RELOCS (buf);
+ rel = GET_RELOC (buf);
+ if (rel == NULL)
+ /* This should not happen. */
+ goto free_no_table;
+ if ((*reloc_symbol_deleted_p) (buf - ehbuf, cookie))
+ {
+ cookie->rel = rel;
+ /* This is a FDE against discarded section, it should
+ be deleted. */
+ new_size -= hdr.length + 4;
+ sec_info->entry[sec_info->count].removed = 1;
+ }
+ else
+ {
+ cie_usage_count++;
+ hdr_info->fde_count++;
+ }
+ cookie->rel = rel;
+ buf = last_fde + 4 + hdr.length;
+ SKIP_RELOCS (buf);
+ }
+
+ sec_info->entry[sec_info->count].fde_encoding = cie.fde_encoding;
+ sec_info->count++;
+ }
+
+ elf_section_data (sec)->sec_info = sec_info;
+ elf_section_data (sec)->sec_info_type = ELF_INFO_TYPE_EH_FRAME;
+
+ /* Ok, now we can assign new offsets. */
+ offset = 0;
+ last_cie_ndx = 0;
+ for (i = 0; i < sec_info->count; i++)
+ {
+ if (! sec_info->entry[i].removed)
+ {
+ sec_info->entry[i].new_offset = offset;
+ offset += sec_info->entry[i].size;
+ if (sec_info->entry[i].cie)
+ {
+ last_cie_ndx = i;
+ make_relative = sec_info->entry[i].make_relative;
+ }
+ else
+ sec_info->entry[i].make_relative = make_relative;
+ }
+ else if (sec_info->entry[i].cie && sec_info->entry[i].sec == sec)
+ {
+ /* Need to adjust new_offset too. */
+ BFD_ASSERT (sec_info->entry[last_cie_ndx].offset
+ == sec_info->entry[i].new_offset);
+ sec_info->entry[i].new_offset
+ = sec_info->entry[last_cie_ndx].new_offset;
+ }
+ }
+ if (hdr_info->last_cie_sec == sec)
+ {
+ BFD_ASSERT (sec_info->entry[last_cie_ndx].offset
+ == hdr_info->last_cie_offset);
+ hdr_info->last_cie_offset = sec_info->entry[last_cie_ndx].new_offset;
+ }
+
+ /* Shrink the sec as needed. */
+
+ sec->_cooked_size = new_size;
+ if (sec->_cooked_size == 0)
+ sec->flags |= SEC_EXCLUDE;
+
+ return new_size != sec->_raw_size;
+
+free_no_table:
+ if (sec_info)
+ free (sec_info);
+ hdr_info->table = false;
+ hdr_info->last_cie.hdr.length = 0;
+ return false;
+}
+
+/* This function is called for .eh_frame_hdr section after
+ _bfd_elf_discard_section_eh_frame has been called on all .eh_frame
+ input sections. It finalizes the size of .eh_frame_hdr section. */
+
+boolean
+_bfd_elf_discard_section_eh_frame_hdr (abfd, info, sec)
+ bfd *abfd;
+ struct bfd_link_info *info;
+ asection *sec;
+{
+ struct eh_frame_hdr_info *hdr_info;
+ unsigned int ptr_size;
+
+ ptr_size = (elf_elfheader (abfd)->e_ident[EI_CLASS]
+ == ELFCLASS64) ? 8 : 4;
+
+ if (elf_section_data (sec)->sec_info_type
+ != ELF_INFO_TYPE_EH_FRAME_HDR)
+ {
+ _bfd_strip_section_from_output (info, sec);
+ return false;
+ }
+
+ hdr_info = (struct eh_frame_hdr_info *)
+ elf_section_data (sec)->sec_info;
+ sec->_cooked_size = EH_FRAME_HDR_SIZE;
+ if (hdr_info->table)
+ sec->_cooked_size += 4 + hdr_info->fde_count * 8;
+
+ /* Request program headers to be recalculated. */
+ elf_tdata (abfd)->program_header_size = 0;
+ elf_tdata (abfd)->eh_frame_hdr = true;
+ return true;
+}
+
+/* Adjust an address in the .eh_frame section. Given OFFSET within
+ SEC, this returns the new offset in the adjusted .eh_frame section,
+ or -1 if the address refers to a CIE/FDE which has been removed
+ or to offset with dynamic relocation which is no longer needed. */
+
+bfd_vma
+_bfd_elf_eh_frame_section_offset (output_bfd, sec, offset)
+ bfd *output_bfd ATTRIBUTE_UNUSED;
+ asection *sec;
+ bfd_vma offset;
+{
+ struct eh_frame_sec_info *sec_info;
+ unsigned int lo, hi, mid;
+
+ if (elf_section_data (sec)->sec_info_type != ELF_INFO_TYPE_EH_FRAME)
+ return offset;
+ sec_info = (struct eh_frame_sec_info *)
+ elf_section_data (sec)->sec_info;
+
+ if (offset >= sec->_raw_size)
+ return offset - (sec->_cooked_size - sec->_raw_size);
+
+ lo = 0;
+ hi = sec_info->count;
+ mid = 0;
+ while (lo < hi)
+ {
+ mid = (lo + hi) / 2;
+ if (offset < sec_info->entry[mid].offset)
+ hi = mid;
+ else if (offset
+ >= sec_info->entry[mid].offset + sec_info->entry[mid].size)
+ lo = mid + 1;
+ else
+ break;
+ }
+
+ BFD_ASSERT (lo < hi);
+
+ /* FDE or CIE was removed. */
+ if (sec_info->entry[mid].removed)
+ return (bfd_vma) -1;
+
+ /* If converting to DW_EH_PE_pcrel, there will be no need for run-time
+ relocation against FDE's initial_location field. */
+ if (sec_info->entry[mid].make_relative
+ && ! sec_info->entry[mid].cie
+ && offset == sec_info->entry[mid].offset + 8)
+ return (bfd_vma) -1;
+
+ return offset
+ + (sec_info->entry[mid].new_offset - sec_info->entry[mid].offset);
+}
+
+/* Write out .eh_frame section. This is called with the relocated
+ contents. */
+
+boolean
+_bfd_elf_write_section_eh_frame (abfd, sec, ehdrsec, contents)
+ bfd *abfd;
+ asection *sec, *ehdrsec;
+ bfd_byte *contents;
+{
+ struct eh_frame_sec_info *sec_info;
+ struct eh_frame_hdr_info *hdr_info;
+ unsigned int i;
+ bfd_byte *p, *buf;
+ unsigned int leb128_tmp;
+ unsigned int cie_offset = 0;
+ unsigned int ptr_size;
+
+ ptr_size = (elf_elfheader (sec->owner)->e_ident[EI_CLASS]
+ == ELFCLASS64) ? 8 : 4;
+
+ if (elf_section_data (sec)->sec_info_type != ELF_INFO_TYPE_EH_FRAME)
+ return bfd_set_section_contents (abfd, sec->output_section,
+ contents,
+ (file_ptr) sec->output_offset,
+ sec->_raw_size);
+ sec_info = (struct eh_frame_sec_info *)
+ elf_section_data (sec)->sec_info;
+ hdr_info = NULL;
+ if (ehdrsec
+ && (elf_section_data (ehdrsec)->sec_info_type
+ == ELF_INFO_TYPE_EH_FRAME_HDR))
+ {
+ hdr_info = (struct eh_frame_hdr_info *)
+ elf_section_data (ehdrsec)->sec_info;
+ if (hdr_info->table && hdr_info->array == NULL)
+ hdr_info->array
+ = bfd_malloc (hdr_info->fde_count * sizeof(*hdr_info->array));
+ if (hdr_info->array == NULL)
+ hdr_info = NULL;
+ }
+
+ p = contents;
+ for (i = 0; i < sec_info->count; ++i)
+ {
+ if (sec_info->entry[i].removed)
+ {
+ if (sec_info->entry[i].cie)
+ {
+ cie_offset = sec_info->entry[i].new_offset;
+ cie_offset += sec_info->entry[i].sec->output_section->vma
+ + sec_info->entry[i].sec->output_offset
+ - sec->output_section->vma
+ - sec->output_offset;
+ }
+ continue;
+ }
+ if (sec_info->entry[i].cie)
+ {
+ /* CIE */
+ cie_offset = sec_info->entry[i].new_offset;
+ if (sec_info->entry[i].make_relative)
+ {
+ unsigned char *aug;
+ unsigned int dummy, per_width, per_encoding;
+
+ /* Need to find 'R' augmentation's argument and modify
+ DW_EH_PE_* value. */
+ buf = contents + sec_info->entry[i].offset;
+ /* Skip length, id and version. */
+ buf += 9;
+ aug = buf;
+ buf = strchr (buf, '\0') + 1;
+ read_uleb128 (dummy, buf);
+ read_sleb128 (dummy, buf);
+ read_uleb128 (dummy, buf);
+ if (*aug == 'z')
+ {
+ read_uleb128 (dummy, buf);
+ aug++;
+ }
+
+ while (*aug != 'R')
+ switch (*aug++)
+ {
+ case 'L':
+ buf++;
+ break;
+ case 'P':
+ per_encoding = *buf++;
+ per_width = get_DW_EH_PE_width (per_encoding,
+ ptr_size);
+ BFD_ASSERT (per_width != 0);
+ if ((per_encoding & 0xf0) == DW_EH_PE_aligned)
+ buf = contents
+ + ((buf - contents + per_width - 1)
+ & ~((bfd_size_type) per_width - 1));
+ buf += per_width;
+ break;
+ default:
+ BFD_FAIL ();
+ }
+
+ BFD_ASSERT (*buf == sec_info->entry[i].fde_encoding);
+ *buf |= DW_EH_PE_pcrel;
+ }
+ }
+ else
+ {
+ /* FDE */
+ bfd_vma value = 0, address;
+ unsigned int fde_width;
+
+ buf = contents + sec_info->entry[i].offset;
+ /* Skip length. */
+ buf += 4;
+ bfd_put_32 (abfd,
+ sec_info->entry[i].new_offset + 4 - cie_offset, buf);
+ buf += 4;
+ fde_width = get_DW_EH_PE_width (sec_info->entry[i].fde_encoding,
+ ptr_size);
+ switch (fde_width)
+ {
+ case 2: value = bfd_get_16 (abfd, buf); break;
+ case 4: value = bfd_get_32 (abfd, buf); break;
+ case 8: value = bfd_get_64 (abfd, buf); break;
+ default: BFD_FAIL ();
+ }
+ address = value;
+ switch (sec_info->entry[i].fde_encoding & 0xf0)
+ {
+ case DW_EH_PE_indirect:
+ case DW_EH_PE_textrel:
+ BFD_ASSERT (hdr_info == NULL);
+ break;
+ case DW_EH_PE_datarel:
+ {
+ asection *got = bfd_get_section_by_name (abfd, ".got");
+
+ BFD_ASSERT (got != NULL);
+ address += got->vma;
+ }
+ break;
+ case DW_EH_PE_pcrel:
+ value += sec_info->entry[i].offset
+ - sec_info->entry[i].new_offset;
+ address += sec->output_section->vma + sec->output_offset
+ + sec_info->entry[i].new_offset + 8;
+ break;
+ }
+ if (sec_info->entry[i].make_relative)
+ value -= sec->output_section->vma + sec->output_offset
+ + sec_info->entry[i].new_offset + 8;
+ switch (fde_width)
+ {
+ case 2: bfd_put_16 (abfd, value, buf); break;
+ case 4: bfd_put_32 (abfd, value, buf); break;
+ case 8: bfd_put_64 (abfd, value, buf); break;
+ }
+
+ if (hdr_info)
+ {
+ hdr_info->array[hdr_info->array_count].initial_loc = address;
+ hdr_info->array[hdr_info->array_count++].fde
+ = sec->output_section->vma + sec->output_offset
+ + sec_info->entry[i].new_offset;
+ }
+ }
+
+ BFD_ASSERT (p == contents + sec_info->entry[i].new_offset);
+ memmove (p, contents + sec_info->entry[i].offset,
+ sec_info->entry[i].size);
+ p += sec_info->entry[i].size;
+ }
+
+ BFD_ASSERT ((bfd_size_type) (p - contents) == sec->_cooked_size);
+
+ return bfd_set_section_contents (abfd, sec->output_section,
+ contents, (file_ptr) sec->output_offset,
+ sec->_cooked_size);
+}
+
+/* Helper function used to sort .eh_frame_hdr search table by increasing
+ VMA of FDE initial location. */
+
+static int
+vma_compare (a, b)
+ const PTR a;
+ const PTR b;
+{
+ struct eh_frame_array_ent *p = (struct eh_frame_array_ent *) a;
+ struct eh_frame_array_ent *q = (struct eh_frame_array_ent *) b;
+ if (p->initial_loc > q->initial_loc)
+ return 1;
+ if (p->initial_loc < q->initial_loc)
+ return -1;
+ return 0;
+}
+
+/* Write out .eh_frame_hdr section. This must be called after
+ _bfd_elf_write_section_eh_frame has been called on all input
+ .eh_frame sections.
+ .eh_frame_hdr format:
+ ubyte version (currently 1)
+ ubyte eh_frame_ptr_enc (DW_EH_PE_* encoding of pointer to start of
+ .eh_frame section)
+ ubyte fde_count_enc (DW_EH_PE_* encoding of total FDE count
+ number (or DW_EH_PE_omit if there is no
+ binary search table computed))
+ ubyte table_enc (DW_EH_PE_* encoding of binary search table,
+ or DW_EH_PE_omit if not present.
+ DW_EH_PE_datarel is using address of
+ .eh_frame_hdr section start as base)
+ [encoded] eh_frame_ptr (pointer to start of .eh_frame section)
+ optionally followed by:
+ [encoded] fde_count (total number of FDEs in .eh_frame section)
+ fde_count x [encoded] initial_loc, fde
+ (array of encoded pairs containing
+ FDE initial_location field and FDE address,
+ sorted by increasing initial_loc) */
+
+boolean
+_bfd_elf_write_section_eh_frame_hdr (abfd, sec)
+ bfd *abfd;
+ asection *sec;
+{
+ struct eh_frame_hdr_info *hdr_info;
+ unsigned int ptr_size;
+ bfd_byte *contents;
+ asection *eh_frame_sec;
+ bfd_size_type size;
+
+ ptr_size = (elf_elfheader (sec->owner)->e_ident[EI_CLASS]
+ == ELFCLASS64) ? 8 : 4;
+
+ BFD_ASSERT (elf_section_data (sec)->sec_info_type
+ == ELF_INFO_TYPE_EH_FRAME_HDR);
+ hdr_info = (struct eh_frame_hdr_info *)
+ elf_section_data (sec)->sec_info;
+ size = EH_FRAME_HDR_SIZE;
+ if (hdr_info->array && hdr_info->array_count == hdr_info->fde_count)
+ size += 4 + hdr_info->fde_count * 8;
+ contents = bfd_malloc (size);
+ if (contents == NULL)
+ return false;
+
+ eh_frame_sec = bfd_get_section_by_name (abfd, ".eh_frame");
+ if (eh_frame_sec == NULL)
+ return false;
+
+ memset (contents, 0, EH_FRAME_HDR_SIZE);
+ contents[0] = 1; /* Version */
+ contents[1] = DW_EH_PE_pcrel | DW_EH_PE_sdata4; /* .eh_frame offset */
+ if (hdr_info->array && hdr_info->array_count == hdr_info->fde_count)
+ {
+ contents[2] = DW_EH_PE_udata4; /* FDE count encoding */
+ contents[3] = DW_EH_PE_datarel | DW_EH_PE_sdata4; /* search table enc */
+ }
+ else
+ {
+ contents[2] = DW_EH_PE_omit;
+ contents[3] = DW_EH_PE_omit;
+ }
+ bfd_put_32 (abfd, eh_frame_sec->vma - sec->output_section->vma - 4,
+ contents + 4);
+ if (contents[2] != DW_EH_PE_omit)
+ {
+ unsigned int i;
+
+ bfd_put_32 (abfd, hdr_info->fde_count, contents + EH_FRAME_HDR_SIZE);
+ qsort (hdr_info->array, hdr_info->fde_count, sizeof (*hdr_info->array),
+ vma_compare);
+ for (i = 0; i < hdr_info->fde_count; i++)
+ {
+ bfd_put_32 (abfd,
+ hdr_info->array[i].initial_loc
+ - sec->output_section->vma,
+ contents + EH_FRAME_HDR_SIZE + i * 8 + 4);
+ bfd_put_32 (abfd,
+ hdr_info->array[i].fde - sec->output_section->vma,
+ contents + EH_FRAME_HDR_SIZE + i * 8 + 8);
+ }
+ }
+
+ return bfd_set_section_contents (abfd, sec->output_section,
+ contents, (file_ptr) sec->output_offset,
+ sec->_cooked_size);
+}
--- bfd/elflink.h.jj Wed Dec 5 14:42:28 2001
+++ bfd/elflink.h Wed Dec 12 20:10:29 2001
@@ -2214,7 +2214,7 @@ elf_link_add_object_symbols (abfd, info)
asection *stab, *stabstr;
stab = bfd_get_section_by_name (abfd, ".stab");
- if (stab != NULL)
+ if (stab != NULL && !(stab->flags & SEC_MERGE))
{
stabstr = bfd_get_section_by_name (abfd, ".stabstr");
@@ -2226,8 +2226,10 @@ elf_link_add_object_symbols (abfd, info)
if (! _bfd_link_section_stabs (abfd,
& hash_table->stab_info,
stab, stabstr,
- &secdata->stab_info))
+ &secdata->sec_info))
goto error_return;
+ if (secdata->sec_info)
+ secdata->sec_info_type = ELF_INFO_TYPE_STABS;
}
}
}
@@ -2238,10 +2240,18 @@ elf_link_add_object_symbols (abfd, info)
asection *s;
for (s = abfd->sections; s != NULL; s = s->next)
- if ((s->flags & SEC_MERGE)
- && ! _bfd_merge_section (abfd, & hash_table->merge_info, s,
- & elf_section_data (s)->merge_info))
- goto error_return;
+ if (s->flags & SEC_MERGE)
+ {
+ struct bfd_elf_section_data *secdata;
+
+ secdata = elf_section_data (s);
+ if (! _bfd_merge_section (abfd,
+ & hash_table->merge_info,
+ s, &secdata->sec_info))
+ goto error_return;
+ else if (secdata->sec_info)
+ secdata->sec_info_type = ELF_INFO_TYPE_MERGE;
+ }
}
return true;
@@ -2300,6 +2310,15 @@ elf_link_create_dynamic_sections (abfd,
return false;
}
+ if (info->eh_frame_hdr)
+ {
+ s = bfd_make_section (abfd, ".eh_frame_hdr");
+ if (s == NULL
+ || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
+ || ! bfd_set_section_alignment (abfd, s, 2))
+ return false;
+ }
+
/* Create sections to hold version informations. These are removed
if they are not needed. */
s = bfd_make_section (abfd, ".gnu.version_d");
@@ -5522,6 +5541,13 @@ elf_bfd_final_link (abfd, info)
goto error_return;
}
+ o = bfd_get_section_by_name (elf_hash_table (info)->dynobj, ".eh_frame_hdr");
+ if (o && elf_section_data (o)->sec_info_type == ELF_INFO_TYPE_EH_FRAME_HDR)
+ {
+ if (! _bfd_elf_write_section_eh_frame_hdr (abfd, o))
+ goto error_return;
+ }
+
if (finfo.symstrtab != NULL)
_bfd_stringtab_free (finfo.symstrtab);
if (finfo.contents != NULL)
@@ -5671,14 +5697,14 @@ elf_link_sec_merge_syms (h, data)
if ((h->root.type == bfd_link_hash_defined
|| h->root.type == bfd_link_hash_defweak)
&& ((sec = h->root.u.def.section)->flags & SEC_MERGE)
- && elf_section_data (sec)->merge_info)
+ && elf_section_data (sec)->sec_info_type == ELF_INFO_TYPE_MERGE)
{
bfd *output_bfd = (bfd *) data;
h->root.u.def.value =
_bfd_merged_section_offset (output_bfd,
&h->root.u.def.section,
- elf_section_data (sec)->merge_info,
+ elf_section_data (sec)->sec_info,
h->root.u.def.value, (bfd_vma) 0);
}
@@ -6170,11 +6196,12 @@ elf_link_input_bfd (finfo, input_bfd)
else if (isym->st_shndx > 0 && isym->st_shndx < SHN_LORESERVE)
{
isec = section_from_elf_index (input_bfd, isym->st_shndx);
- if (isec && elf_section_data (isec)->merge_info
+ if (isec
+ && elf_section_data (isec)->sec_info_type == ELF_INFO_TYPE_MERGE
&& ELF_ST_TYPE (isym->st_info) != STT_SECTION)
isym->st_value =
_bfd_merged_section_offset (output_bfd, &isec,
- elf_section_data (isec)->merge_info,
+ elf_section_data (isec)->sec_info,
isym->st_value, (bfd_vma) 0);
}
else if (isym->st_shndx == SHN_ABS)
@@ -6358,8 +6385,8 @@ elf_link_input_bfd (finfo, input_bfd)
&& ! bfd_is_abs_section (h->root.u.def.section)
&& bfd_is_abs_section (h->root.u.def.section
->output_section)
- && elf_section_data (h->root.u.def.section)->merge_info
- == NULL)
+ && (elf_section_data (h->root.u.def.section)
+ ->sec_info_type != ELF_INFO_TYPE_MERGE))
{
#if BFD_VERSION_DATE < 20031005
if ((o->flags & SEC_DEBUGGING) != 0)
@@ -6391,7 +6418,8 @@ elf_link_input_bfd (finfo, input_bfd)
if (sec != NULL
&& ! bfd_is_abs_section (sec)
&& bfd_is_abs_section (sec->output_section)
- && elf_section_data (sec)->merge_info == NULL)
+ && (elf_section_data (sec)->sec_info_type
+ != ELF_INFO_TYPE_MERGE))
{
#if BFD_VERSION_DATE < 20031005
if ((o->flags & SEC_DEBUGGING) != 0
@@ -6640,30 +6668,45 @@ elf_link_input_bfd (finfo, input_bfd)
{
/* Section written out. */
}
- else if (elf_section_data (o)->stab_info)
+ else switch (elf_section_data (o)->sec_info_type)
{
+ case ELF_INFO_TYPE_STABS:
if (! (_bfd_write_section_stabs
- (output_bfd, &elf_hash_table (finfo->info)->stab_info,
- o, &elf_section_data (o)->stab_info, contents)))
+ (output_bfd,
+ &elf_hash_table (finfo->info)->stab_info,
+ o, &elf_section_data (o)->sec_info, contents)))
return false;
- }
- else if (elf_section_data (o)->merge_info)
- {
+ break;
+ case ELF_INFO_TYPE_MERGE:
if (! (_bfd_write_merged_section
- (output_bfd, o, elf_section_data (o)->merge_info)))
+ (output_bfd, o, elf_section_data (o)->sec_info)))
return false;
- }
- else
- {
- bfd_size_type sec_size;
+ break;
+ case ELF_INFO_TYPE_EH_FRAME:
+ {
+ asection *ehdrsec;
- sec_size = (o->_cooked_size != 0 ? o->_cooked_size : o->_raw_size);
- if (! (o->flags & SEC_EXCLUDE)
- && ! bfd_set_section_contents (output_bfd, o->output_section,
- contents,
- (file_ptr) o->output_offset,
- sec_size))
- return false;
+ ehdrsec
+ = bfd_get_section_by_name (elf_hash_table (finfo->info)->dynobj,
+ ".eh_frame_hdr");
+ if (! (_bfd_elf_write_section_eh_frame (output_bfd, o, ehdrsec,
+ contents)))
+ return false;
+ }
+ break;
+ default:
+ {
+ bfd_size_type sec_size;
+
+ sec_size = (o->_cooked_size != 0 ? o->_cooked_size : o->_raw_size);
+ if (! (o->flags & SEC_EXCLUDE)
+ && ! bfd_set_section_contents (output_bfd, o->output_section,
+ contents,
+ (file_ptr) o->output_offset,
+ sec_size))
+ return false;
+ }
+ break;
}
}
@@ -7881,24 +7924,30 @@ elf_reloc_symbol_deleted_p (offset, cook
which is true for all known assemblers. */
boolean
-elf_bfd_discard_info (info)
+elf_bfd_discard_info (output_bfd, info)
+ bfd *output_bfd;
struct bfd_link_info *info;
{
struct elf_reloc_cookie cookie;
- asection *o;
+ asection *stab, *eh, *ehdr;
Elf_Internal_Shdr *symtab_hdr;
Elf_External_Sym *freesyms;
struct elf_backend_data *bed;
bfd *abfd;
boolean ret = false;
+ boolean strip = info->strip == strip_all || info->strip == strip_debugger;
if (info->relocateable
|| info->traditional_format
|| info->hash->creator->flavour != bfd_target_elf_flavour
- || ! is_elf_hash_table (info)
- || info->strip == strip_all
- || info->strip == strip_debugger)
+ || ! is_elf_hash_table (info))
return false;
+
+ ehdr = NULL;
+ if (info->eh_frame_hdr)
+ ehdr = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
+ ".eh_frame_hdr");
+
for (abfd = info->input_bfds; abfd != NULL; abfd = abfd->link_next)
{
if (bfd_get_flavour (abfd) != bfd_target_elf_flavour)
@@ -7909,8 +7958,18 @@ elf_bfd_discard_info (info)
if ((abfd->flags & DYNAMIC) != 0)
continue;
- o = bfd_get_section_by_name (abfd, ".stab");
- if (! o && ! bed->elf_backend_discard_info)
+ eh = NULL;
+ if (ehdr)
+ {
+ eh = bfd_get_section_by_name (abfd, ".eh_frame");
+ if (eh && eh->_raw_size == 0)
+ eh = NULL;
+ }
+
+ stab = strip ? NULL : bfd_get_section_by_name (abfd, ".stab");
+ if ((! stab || elf_section_data(stab)->sec_info_type != ELF_INFO_TYPE_STABS)
+ && ! eh
+ && (strip || ! bed->elf_backend_discard_info))
continue;
symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
@@ -7955,19 +8014,19 @@ elf_bfd_discard_info (info)
}
}
- if (o)
+ if (stab)
{
cookie.rels = (NAME(_bfd_elf,link_read_relocs)
- (abfd, o, (PTR) NULL,
+ (abfd, stab, (PTR) NULL,
(Elf_Internal_Rela *) NULL,
info->keep_memory));
if (cookie.rels)
{
cookie.rel = cookie.rels;
cookie.relend =
- cookie.rels + o->reloc_count * bed->s->int_rels_per_ext_rel;
- if (_bfd_discard_section_stabs (abfd, o,
- elf_section_data (o)->stab_info,
+ cookie.rels + stab->reloc_count * bed->s->int_rels_per_ext_rel;
+ if (_bfd_discard_section_stabs (abfd, stab,
+ elf_section_data (stab)->sec_info,
elf_reloc_symbol_deleted_p,
&cookie))
ret = true;
@@ -7976,6 +8035,30 @@ elf_bfd_discard_info (info)
}
}
+ if (eh)
+ {
+ cookie.rels = NULL;
+ cookie.rel = NULL;
+ cookie.relend = NULL;
+ if (eh->reloc_count)
+ cookie.rels = (NAME(_bfd_elf,link_read_relocs)
+ (abfd, eh, (PTR) NULL,
+ (Elf_Internal_Rela *) NULL,
+ info->keep_memory));
+ if (cookie.rels)
+ {
+ cookie.rel = cookie.rels;
+ cookie.relend =
+ cookie.rels + eh->reloc_count * bed->s->int_rels_per_ext_rel;
+ }
+ if (_bfd_elf_discard_section_eh_frame (abfd, info, eh, ehdr,
+ elf_reloc_symbol_deleted_p,
+ &cookie))
+ ret = true;
+ if (! info->keep_memory)
+ free (cookie.rels);
+ }
+
if (bed->elf_backend_discard_info)
{
if (bed->elf_backend_discard_info (abfd, &cookie, info))
@@ -7985,6 +8068,11 @@ elf_bfd_discard_info (info)
if (freesyms)
free (freesyms);
}
+
+ if (ehdr
+ && _bfd_elf_discard_section_eh_frame_hdr (output_bfd,
+ info, ehdr))
+ ret = true;
return ret;
}
@@ -7992,13 +8080,19 @@ static boolean
elf_section_ignore_discarded_relocs (sec)
asection *sec;
{
- if (strcmp (sec->name, ".stab") == 0)
- return true;
- else if ((get_elf_backend_data (sec->owner)
- ->elf_backend_ignore_discarded_relocs != NULL)
- && (*get_elf_backend_data (sec->owner)
- ->elf_backend_ignore_discarded_relocs) (sec))
+ switch (elf_section_data (sec)->sec_info_type)
+ {
+ case ELF_INFO_TYPE_STABS:
+ case ELF_INFO_TYPE_EH_FRAME:
+ return true;
+ default:
+ break;
+ }
+ if ((get_elf_backend_data (sec->owner)->elf_backend_ignore_discarded_relocs
+ != NULL)
+ && (*get_elf_backend_data (sec->owner)
+ ->elf_backend_ignore_discarded_relocs) (sec))
return true;
- else
- return false;
+
+ return false;
}
--- bfd/bfd-in.h.jj Fri Nov 16 21:49:42 2001
+++ bfd/bfd-in.h Fri Dec 7 13:32:51 2001
@@ -636,9 +636,9 @@ extern const char *bfd_elf_get_dt_soname
extern struct bfd_link_needed_list *bfd_elf_get_runpath_list
PARAMS ((bfd *, struct bfd_link_info *));
extern boolean bfd_elf32_discard_info
- PARAMS ((struct bfd_link_info *));
+ PARAMS ((bfd *, struct bfd_link_info *));
extern boolean bfd_elf64_discard_info
- PARAMS ((struct bfd_link_info *));
+ PARAMS ((bfd *, struct bfd_link_info *));
/* Return an upper bound on the number of bytes required to store a
copy of ABFD's program header table entries. Return -1 if an error
--- bfd/bfd-in2.h.jj Wed Dec 5 14:42:24 2001
+++ bfd/bfd-in2.h Fri Dec 7 13:32:51 2001
@@ -642,9 +642,9 @@ extern const char *bfd_elf_get_dt_soname
extern struct bfd_link_needed_list *bfd_elf_get_runpath_list
PARAMS ((bfd *, struct bfd_link_info *));
extern boolean bfd_elf32_discard_info
- PARAMS ((struct bfd_link_info *));
+ PARAMS ((bfd *, struct bfd_link_info *));
extern boolean bfd_elf64_discard_info
- PARAMS ((struct bfd_link_info *));
+ PARAMS ((bfd *, struct bfd_link_info *));
/* Return an upper bound on the number of bytes required to store a
copy of ABFD's program header table entries. Return -1 if an error
--- bfd/elf-bfd.h.jj Fri Dec 7 13:22:19 2001
+++ bfd/elf-bfd.h Mon Dec 10 14:17:42 2001
@@ -223,6 +223,16 @@ struct elf_link_local_dynamic_entry
Elf_Internal_Sym isym;
};
+enum elf_link_info_type
+{
+ ELF_INFO_TYPE_NONE,
+ ELF_INFO_TYPE_STABS,
+ ELF_INFO_TYPE_MERGE,
+ ELF_INFO_TYPE_EH_FRAME,
+ ELF_INFO_TYPE_EH_FRAME_HDR,
+ ELF_INFO_TYPE_LAST
+};
+
/* ELF linker hash table. */
struct elf_link_hash_table
@@ -848,11 +858,11 @@ struct bfd_elf_section_data
no dynamic symbol for this section. */
long dynindx;
- /* A pointer used for .stab linking optimizations. */
- PTR stab_info;
+ /* A pointer used for various section optimizations. */
+ PTR sec_info;
- /* A pointer used for SEC_MERGE optimizations. */
- PTR merge_info;
+ /* Type of that information. */
+ enum elf_link_info_type sec_info_type;
/* Group name, if this section is part of a group. */
const char *group_name;
@@ -1043,6 +1053,10 @@ struct elf_obj_tdata
/* Used to determine if the e_flags field has been initialized */
boolean flags_init;
+ /* Used to determine if PT_GNU_EH_FRAME segment header should be
+ created. */
+ boolean eh_frame_hdr;
+
/* Number of symbol version definitions we are about to emit. */
unsigned int cverdefs;
@@ -1271,6 +1285,18 @@ extern boolean _bfd_elf_strtab_emit
extern void _bfd_elf_strtab_finalize
PARAMS ((struct elf_strtab_hash *));
+extern boolean _bfd_elf_discard_section_eh_frame
+ PARAMS ((bfd *, struct bfd_link_info *, asection *, asection *,
+ boolean (*) (bfd_vma, PTR), struct elf_reloc_cookie *));
+extern boolean _bfd_elf_discard_section_eh_frame_hdr
+ PARAMS ((bfd *, struct bfd_link_info *, asection *));
+extern bfd_vma _bfd_elf_eh_frame_section_offset
+ PARAMS ((bfd *, asection *, bfd_vma));
+extern boolean _bfd_elf_write_section_eh_frame
+ PARAMS ((bfd *, asection *, asection *, bfd_byte *));
+extern boolean _bfd_elf_write_section_eh_frame_hdr
+ PARAMS ((bfd *, asection *));
+
extern boolean _bfd_elf_link_record_dynamic_symbol
PARAMS ((struct bfd_link_info *, struct elf_link_hash_entry *));
extern long _bfd_elf_link_lookup_local_dynindx
--- bfd/Makefile.am.jj Fri Dec 7 12:59:23 2001
+++ bfd/Makefile.am Fri Dec 7 16:37:25 2001
@@ -220,6 +220,7 @@ BFD32_BACKENDS = \
elf32.lo \
elflink.lo \
elf-strtab.lo \
+ elf-eh-frame.lo \
epoc-pe-arm.lo \
epoc-pei-arm.lo \
hp300bsd.lo \
@@ -361,6 +362,7 @@ BFD32_BACKENDS_CFILES = \
elf32.c \
elflink.c \
elf-strtab.c \
+ elf-eh-frame.c \
epoc-pe-arm.c \
epoc-pei-arm.c \
hp300bsd.c \
@@ -1140,6 +1142,7 @@ elflink.lo: elflink.c $(INCDIR)/filename
elf-bfd.h $(INCDIR)/elf/common.h $(INCDIR)/elf/internal.h \
$(INCDIR)/elf/external.h
elf-strtab.lo: elf-strtab.c $(INCDIR)/filenames.h $(INCDIR)/hashtab.h
+elf-eh-frame.lo: elf-eh-frame.c
epoc-pe-arm.lo: epoc-pe-arm.c pe-arm.c $(INCDIR)/filenames.h \
coff-arm.c $(INCDIR)/coff/arm.h $(INCDIR)/coff/external.h \
$(INCDIR)/coff/internal.h $(INCDIR)/coff/pe.h libcoff.h \
--- bfd/Makefile.in.jj Fri Dec 7 12:59:23 2001
+++ bfd/Makefile.in Fri Dec 7 16:37:55 2001
@@ -348,6 +348,7 @@ BFD32_BACKENDS = \
elf32.lo \
elflink.lo \
elf-strtab.lo \
+ elf-eh-frame.lo \
epoc-pe-arm.lo \
epoc-pei-arm.lo \
hp300bsd.lo \
@@ -490,6 +491,7 @@ BFD32_BACKENDS_CFILES = \
elf32.c \
elflink.c \
elf-strtab.c \
+ elf-eh-frame.c \
epoc-pe-arm.c \
epoc-pei-arm.c \
hp300bsd.c \
@@ -1684,6 +1686,7 @@ elflink.lo: elflink.c $(INCDIR)/filename
elf-bfd.h $(INCDIR)/elf/common.h $(INCDIR)/elf/internal.h \
$(INCDIR)/elf/external.h
elf-strtab.lo: elf-strtab.c $(INCDIR)/filenames.h $(INCDIR)/hashtab.h
+elf-eh-frame.lo: elf-eh-frame.c
epoc-pe-arm.lo: epoc-pe-arm.c pe-arm.c $(INCDIR)/filenames.h \
coff-arm.c $(INCDIR)/coff/arm.h $(INCDIR)/coff/external.h \
$(INCDIR)/coff/internal.h $(INCDIR)/coff/pe.h libcoff.h \
--- bfd/configure.in.jj Fri Dec 7 12:59:50 2001
+++ bfd/configure.in Fri Dec 7 16:38:21 2001
@@ -503,7 +503,7 @@ selarchs="$f"
# Target backend .o files.
tb=
-elf="elf.lo elflink.lo elf-strtab.lo dwarf1.lo"
+elf="elf.lo elflink.lo elf-strtab.lo elf-eh-frame.lo dwarf1.lo"
for vec in $selvecs
do
--- bfd/configure.jj Fri Dec 7 12:59:50 2001
+++ bfd/configure Fri Dec 7 16:38:33 2001
@@ -5910,7 +5910,7 @@ selarchs="$f"
# Target backend .o files.
tb=
-elf="elf.lo elflink.lo elf-strtab.lo dwarf1.lo"
+elf="elf.lo elflink.lo elf-strtab.lo elf-eh-frame.lo dwarf1.lo"
for vec in $selvecs
do
--- include/elf/common.h.jj Fri Nov 16 21:50:36 2001
+++ include/elf/common.h Mon Dec 10 13:22:21 2001
@@ -254,6 +254,8 @@ Foundation, Inc., 59 Temple Place - Suit
#define PT_LOPROC 0x70000000 /* Processor-specific */
#define PT_HIPROC 0x7FFFFFFF /* Processor-specific */
+#define PT_GNU_EH_FRAME (PT_LOOS + 0x474e550)
+
/* Program segment permissions, in program header p_flags field. */
#define PF_X (1 << 0) /* Segment is executable */
--- include/bfdlink.h.jj Fri Oct 5 13:04:02 2001
+++ include/bfdlink.h Wed Dec 12 20:11:32 2001
@@ -298,6 +298,10 @@ struct bfd_link_info
Setting this true may result in a non-sharable text segment. */
boolean nocopyreloc;
+ /* True if .eh_frame_hdr section and PT_GNU_EH_FRAME ELF segment
+ should be created. */
+ boolean eh_frame_hdr;
+
/* How many spare .dynamic DT_NULL entries should be added? */
unsigned int spare_dynamic_tags;
};
--- ld/emultempl/elf32.em.jj Thu Nov 22 11:05:04 2001
+++ ld/emultempl/elf32.em Fri Dec 7 13:32:51 2001
@@ -1329,7 +1329,7 @@ cat >>e${EMULATION_NAME}.c <<EOF
static void
gld${EMULATION_NAME}_finish ()
{
- if (bfd_elf${ELFSIZE}_discard_info (&link_info))
+ if (bfd_elf${ELFSIZE}_discard_info (output_bfd, &link_info))
{
/* Resize the sections. */
lang_size_sections (stat_ptr->head, abs_output_section,
@@ -1431,6 +1431,7 @@ cat >>e${EMULATION_NAME}.c <<EOF
#define OPTION_DISABLE_NEW_DTAGS (400)
#define OPTION_ENABLE_NEW_DTAGS (OPTION_DISABLE_NEW_DTAGS + 1)
#define OPTION_GROUP (OPTION_ENABLE_NEW_DTAGS + 1)
+#define OPTION_EH_FRAME_HDR (OPTION_GROUP + 1)
static struct option longopts[] =
{
@@ -1444,6 +1445,7 @@ cat >>e${EMULATION_NAME}.c <<EOF
{"disable-new-dtags", no_argument, NULL, OPTION_DISABLE_NEW_DTAGS},
{"enable-new-dtags", no_argument, NULL, OPTION_ENABLE_NEW_DTAGS},
{"enable-new-dtags", no_argument, NULL, OPTION_ENABLE_NEW_DTAGS},
+ {"eh-frame-hdr", no_argument, NULL, OPTION_EH_FRAME_HDR},
{"Bgroup", no_argument, NULL, OPTION_GROUP},
{"Bgroup", no_argument, NULL, OPTION_GROUP},
EOF
@@ -1504,6 +1506,10 @@ cat >>e${EMULATION_NAME}.c <<EOF
link_info.new_dtags = true;
break;
+ case OPTION_EH_FRAME_HDR:
+ link_info.eh_frame_hdr = true;
+ break;
+
case OPTION_GROUP:
link_info.flags_1 |= (bfd_vma) DF_1_GROUP;
/* Groups must be self-contained. */
@@ -1579,6 +1585,7 @@ cat >>e${EMULATION_NAME}.c <<EOF
fprintf (file, _(" -Bgroup\t\tSelects group name lookup rules for DSO\n"));
fprintf (file, _(" --disable-new-dtags\tDisable new dynamic tags\n"));
fprintf (file, _(" --enable-new-dtags\tEnable new dynamic tags\n"));
+ fprintf (file, _(" --eh-frame-hdr\tCreate .eh_frame_hdr section\n"));
fprintf (file, _(" -z combreloc\t\tMerge dynamic relocs into one section and sort\n"));
fprintf (file, _(" -z defs\t\tDisallows undefined symbols\n"));
fprintf (file, _(" -z initfirst\t\tMark DSO to be initialized first at runtime\n"));
--- ld/emultempl/hppaelf.em.jj Thu Nov 22 11:05:04 2001
+++ ld/emultempl/hppaelf.em Fri Dec 7 13:32:51 2001
@@ -254,7 +254,7 @@ gld${EMULATION_NAME}_finish ()
ie. doesn't affect any code, so we can delay resizing the
sections. It's likely we'll resize everything in the process of
adding stubs. */
- if (bfd_elf${ELFSIZE}_discard_info (&link_info))
+ if (bfd_elf${ELFSIZE}_discard_info (output_bfd, &link_info))
need_laying_out = 1;
/* Call into the BFD backend to do the real work. */
--- ld/scripttempl/elf.sc.jj Wed Nov 28 21:05:08 2001
+++ ld/scripttempl/elf.sc Fri Dec 7 13:32:51 2001
@@ -265,6 +265,7 @@ cat <<EOF
${CREATE_SHLIB-${SDATA2}}
${CREATE_SHLIB-${SBSS2}}
${OTHER_READONLY_SECTIONS}
+ .eh_frame_hdr : { *(.eh_frame_hdr) }
/* Adjust the address for the data segment. We want to adjust up to
the same address within the page on the next page up. */
Jakub