--- /dev/null
+/* .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)
+ || ! info->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);
+}
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");
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;
}
}
}
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;
return false;
}
+ if (! info->traditional_format
+ && info->hash->creator->flavour == bfd_target_elf_flavour)
+ {
+ 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");
goto error_return;
}
+ if (info->eh_frame_hdr)
+ {
+ 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)
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);
}
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)
&& ! 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)
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
{
/* 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)))
- return false;
- }
- else
- {
- 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))
+ (output_bfd, o, elf_section_data (o)->sec_info)))
return false;
+ break;
+ case ELF_INFO_TYPE_EH_FRAME:
+ {
+ asection *ehdrsec;
+
+ 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;
}
}
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 = 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)
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;
}
}
- 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;
}
}
+ 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))
if (freesyms)
free (freesyms);
}
+
+ if (ehdr
+ && _bfd_elf_discard_section_eh_frame_hdr (output_bfd,
+ info, ehdr))
+ ret = true;
return ret;
}
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;
}
projects / external / binutils.git / commitdiff