X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=bfd%2Felf-eh-frame.c;h=7a129b00f8d78fecd8c450ef8aca564eea4a9485;hb=refs%2Fheads%2Fconcurrent-displaced-stepping-2020-04-01;hp=37c92553ce352e90ab452a22a084a177c85f6959;hpb=91d6fa6a035cc7d0b7be5c99c194a64cb80924b0;p=deliverable%2Fbinutils-gdb.git diff --git a/bfd/elf-eh-frame.c b/bfd/elf-eh-frame.c index 37c92553ce..7a129b00f8 100644 --- a/bfd/elf-eh-frame.c +++ b/bfd/elf-eh-frame.c @@ -1,6 +1,5 @@ /* .eh_frame section optimization. - Copyright 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 - Free Software Foundation, Inc. + Copyright (C) 2001-2020 Free Software Foundation, Inc. Written by Jakub Jelinek . This file is part of BFD, the Binary File Descriptor library. @@ -41,10 +40,12 @@ struct cie bfd_vma augmentation_size; union { struct elf_link_hash_entry *h; - bfd_vma val; + struct { + unsigned int bfd_id; + unsigned int index; + } sym; unsigned int reloc_index; } personality; - asection *output_sec; struct eh_cie_fde *cie_inf; unsigned char per_encoding; unsigned char lsda_encoding; @@ -230,11 +231,13 @@ cie_eq (const void *e1, const void *e2) && c1->augmentation_size == c2->augmentation_size && memcmp (&c1->personality, &c2->personality, sizeof (c1->personality)) == 0 - && c1->output_sec == c2->output_sec + && (c1->cie_inf->u.cie.u.sec->output_section + == c2->cie_inf->u.cie.u.sec->output_section) && 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 + && c1->initial_insn_length <= sizeof (c1->initial_instructions) && memcmp (c1->initial_instructions, c2->initial_instructions, c1->initial_insn_length) == 0) @@ -254,6 +257,7 @@ static hashval_t cie_compute_hash (struct cie *c) { hashval_t h = 0; + size_t len; h = iterative_hash_object (c->length, h); h = iterative_hash_object (c->version, h); h = iterative_hash (c->augmentation, strlen (c->augmentation) + 1, h); @@ -262,12 +266,15 @@ cie_compute_hash (struct cie *c) h = iterative_hash_object (c->ra_column, h); h = iterative_hash_object (c->augmentation_size, h); h = iterative_hash_object (c->personality, h); - h = iterative_hash_object (c->output_sec, h); + h = iterative_hash_object (c->cie_inf->u.cie.u.sec->output_section, h); h = iterative_hash_object (c->per_encoding, h); h = iterative_hash_object (c->lsda_encoding, h); h = iterative_hash_object (c->fde_encoding, h); h = iterative_hash_object (c->initial_insn_length, h); - h = iterative_hash (c->initial_instructions, c->initial_insn_length, h); + len = c->initial_insn_length; + if (len > sizeof (c->initial_instructions)) + len = sizeof (c->initial_instructions); + h = iterative_hash (c->initial_instructions, len, h); c->hash = h; return h; } @@ -302,11 +309,10 @@ extra_augmentation_data_bytes (struct eh_cie_fde *entry) return size; } -/* Return the size that ENTRY will have in the output. ALIGNMENT is the - required alignment of ENTRY in bytes. */ +/* Return the size that ENTRY will have in the output. */ static unsigned int -size_of_output_cie_fde (struct eh_cie_fde *entry, unsigned int alignment) +size_of_output_cie_fde (struct eh_cie_fde *entry) { if (entry->removed) return 0; @@ -314,8 +320,22 @@ size_of_output_cie_fde (struct eh_cie_fde *entry, unsigned int alignment) return 4; return (entry->size + extra_augmentation_string_bytes (entry) - + extra_augmentation_data_bytes (entry) - + alignment - 1) & -alignment; + + extra_augmentation_data_bytes (entry)); +} + +/* Return the offset of the FDE or CIE after ENT. */ + +static unsigned int +next_cie_fde_offset (const struct eh_cie_fde *ent, + const struct eh_cie_fde *last, + const asection *sec) +{ + while (++ent < last) + { + if (!ent->removed) + return ent->new_offset; + } + return sec->size; } /* Assume that the bytes between *ITER and END are CFA instructions. @@ -445,16 +465,109 @@ make_pc_relative (unsigned char encoding, unsigned int ptr_size) return encoding | DW_EH_PE_pcrel; } -/* Called before calling _bfd_elf_parse_eh_frame on every input bfd's - .eh_frame section. */ +/* Examine each .eh_frame_entry section and discard those + those that are marked SEC_EXCLUDE. */ -void -_bfd_elf_begin_eh_frame_parsing (struct bfd_link_info *info) +static void +bfd_elf_discard_eh_frame_entry (struct eh_frame_hdr_info *hdr_info) { + unsigned int i; + for (i = 0; i < hdr_info->array_count; i++) + { + if (hdr_info->u.compact.entries[i]->flags & SEC_EXCLUDE) + { + unsigned int j; + for (j = i + 1; j < hdr_info->array_count; j++) + hdr_info->u.compact.entries[j-1] = hdr_info->u.compact.entries[j]; + + hdr_info->array_count--; + hdr_info->u.compact.entries[hdr_info->array_count] = NULL; + i--; + } + } +} + +/* Add a .eh_frame_entry section. */ + +static void +bfd_elf_record_eh_frame_entry (struct eh_frame_hdr_info *hdr_info, + asection *sec) +{ + if (hdr_info->array_count == hdr_info->u.compact.allocated_entries) + { + if (hdr_info->u.compact.allocated_entries == 0) + { + hdr_info->frame_hdr_is_compact = TRUE; + hdr_info->u.compact.allocated_entries = 2; + hdr_info->u.compact.entries = + bfd_malloc (hdr_info->u.compact.allocated_entries + * sizeof (hdr_info->u.compact.entries[0])); + } + else + { + hdr_info->u.compact.allocated_entries *= 2; + hdr_info->u.compact.entries = + bfd_realloc (hdr_info->u.compact.entries, + hdr_info->u.compact.allocated_entries + * sizeof (hdr_info->u.compact.entries[0])); + } + + BFD_ASSERT (hdr_info->u.compact.entries); + } + + hdr_info->u.compact.entries[hdr_info->array_count++] = sec; +} + +/* Parse a .eh_frame_entry section. Figure out which text section it + references. */ + +bfd_boolean +_bfd_elf_parse_eh_frame_entry (struct bfd_link_info *info, + asection *sec, struct elf_reloc_cookie *cookie) +{ + struct elf_link_hash_table *htab; struct eh_frame_hdr_info *hdr_info; + unsigned long r_symndx; + asection *text_sec; - hdr_info = &elf_hash_table (info)->eh_info; - hdr_info->merge_cies = !info->relocatable; + htab = elf_hash_table (info); + hdr_info = &htab->eh_info; + + if (sec->size == 0 + || sec->sec_info_type != SEC_INFO_TYPE_NONE) + { + return TRUE; + } + + if (sec->output_section && 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 TRUE; + } + + if (cookie->rel == cookie->relend) + return FALSE; + + /* The first relocation is the function start. */ + r_symndx = cookie->rel->r_info >> cookie->r_sym_shift; + if (r_symndx == STN_UNDEF) + return FALSE; + + text_sec = _bfd_elf_section_for_symbol (cookie, r_symndx, FALSE); + + if (text_sec == NULL) + return FALSE; + + elf_section_eh_frame_entry (text_sec) = sec; + if (text_sec->output_section + && bfd_is_abs_section (text_sec->output_section)) + sec->flags |= SEC_EXCLUDE; + + sec->sec_info_type = SEC_INFO_TYPE_EH_FRAME_ENTRY; + elf_section_data (sec)->sec_info = text_sec; + bfd_elf_record_eh_frame_entry (hdr_info, sec); + return TRUE; } /* Try to parse .eh_frame section SEC, which belongs to ABFD. Store the @@ -487,10 +600,9 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, htab = elf_hash_table (info); hdr_info = &htab->eh_info; - if (hdr_info->parsed_eh_frames) - return; - if (sec->size == 0) + if (sec->size == 0 + || sec->sec_info_type != SEC_INFO_TYPE_NONE) { /* This file does not contain .eh_frame information. */ return; @@ -507,15 +619,6 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, REQUIRE (bfd_malloc_and_get_section (abfd, sec, &ehbuf)); - if (sec->size >= 4 - && bfd_get_32 (abfd, ehbuf) == 0 - && cookie->rel == cookie->relend) - { - /* Empty .eh_frame section. */ - free (ehbuf); - return; - } - /* 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). */ REQUIRE (sec->size == (unsigned int) sec->size); @@ -553,19 +656,25 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, sec_info = (struct eh_frame_sec_info *) bfd_zmalloc (sizeof (struct eh_frame_sec_info) - + (num_entries - 1) * sizeof (struct eh_cie_fde)); + + (num_entries - 1) * sizeof (struct eh_cie_fde)); REQUIRE (sec_info); /* We need to have a "struct cie" for each CIE in this section. */ - local_cies = (struct cie *) bfd_zmalloc (num_cies * sizeof (*local_cies)); - REQUIRE (local_cies); + if (num_cies) + { + local_cies = (struct cie *) bfd_zmalloc (num_cies * sizeof (*local_cies)); + REQUIRE (local_cies); + } /* FIXME: octets_per_byte. */ #define ENSURE_NO_RELOCS(buf) \ - REQUIRE (!(cookie->rel < cookie->relend \ - && (cookie->rel->r_offset \ - < (bfd_size_type) ((buf) - ehbuf)) \ - && cookie->rel->r_info != 0)) + while (cookie->rel < cookie->relend \ + && (cookie->rel->r_offset \ + < (bfd_size_type) ((buf) - ehbuf))) \ + { \ + REQUIRE (cookie->rel->r_info == 0); \ + cookie->rel++; \ + } /* FIXME: octets_per_byte. */ #define SKIP_RELOCS(buf) \ @@ -609,7 +718,9 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, if (hdr_length == 0) { /* A zero-length CIE should only be found at the end of - the section. */ + the section, but allow multiple terminators. */ + while (skip_bytes (&buf, ehbuf + sec->size, 4)) + REQUIRE (bfd_get_32 (abfd, buf - 4) == 0); REQUIRE ((bfd_size_type) (buf - ehbuf) == sec->size); ENSURE_NO_RELOCS (buf); sec_info->count++; @@ -631,16 +742,18 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, cie->cie_inf = this_inf; cie->length = hdr_length; - cie->output_sec = sec->output_section; start = buf; REQUIRE (read_byte (&buf, end, &cie->version)); /* Cannot handle unknown versions. */ - REQUIRE (cie->version == 1 || cie->version == 3); + REQUIRE (cie->version == 1 + || cie->version == 3 + || cie->version == 4); REQUIRE (strlen ((char *) buf) < sizeof (cie->augmentation)); strcpy (cie->augmentation, (char *) buf); buf = (bfd_byte *) strchr ((char *) buf, '\0') + 1; + this_inf->u.cie.aug_str_len = buf - start - 1; ENSURE_NO_RELOCS (buf); if (buf[0] == 'e' && buf[1] == 'h') { @@ -651,6 +764,13 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, REQUIRE (skip_bytes (&buf, end, ptr_size)); SKIP_RELOCS (buf); } + if (cie->version >= 4) + { + REQUIRE (buf + 1 < end); + REQUIRE (buf[0] == ptr_size); + REQUIRE (buf[1] == 0); + buf += 2; + } REQUIRE (read_uleb128 (&buf, end, &cie->code_align)); REQUIRE (read_sleb128 (&buf, end, &cie->data_align)); if (cie->version == 1) @@ -671,12 +791,14 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, { aug++; REQUIRE (read_uleb128 (&buf, end, &cie->augmentation_size)); - ENSURE_NO_RELOCS (buf); + ENSURE_NO_RELOCS (buf); } while (*aug != '\0') switch (*aug++) { + case 'B': + break; case 'L': REQUIRE (read_byte (&buf, end, &cie->lsda_encoding)); ENSURE_NO_RELOCS (buf); @@ -701,6 +823,8 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, { length = -(buf - ehbuf) & (per_width - 1); REQUIRE (skip_bytes (&buf, end, length)); + if (per_width == 8) + this_inf->u.cie.per_encoding_aligned8 = 1; } this_inf->u.cie.personality_offset = buf - start; ENSURE_NO_RELOCS (buf); @@ -720,10 +844,12 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, goto free_no_table; } } + this_inf->u.cie.aug_data_len + = buf - start - 1 - this_inf->u.cie.aug_str_len; /* For shared libraries, try to get rid of as many RELATIVE relocs as possible. */ - if (info->shared + if (bfd_link_pic (info) && (get_elf_backend_data (abfd) ->elf_backend_can_make_relative_eh_frame (abfd, info, sec))) @@ -752,24 +878,24 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, cie->fde_encoding = DW_EH_PE_absptr; initial_insn_length = end - buf; - if (initial_insn_length <= sizeof (cie->initial_instructions)) - { - cie->initial_insn_length = initial_insn_length; - memcpy (cie->initial_instructions, buf, initial_insn_length); - } + cie->initial_insn_length = initial_insn_length; + memcpy (cie->initial_instructions, buf, + initial_insn_length <= sizeof (cie->initial_instructions) + ? initial_insn_length : sizeof (cie->initial_instructions)); insns = buf; buf += initial_insn_length; ENSURE_NO_RELOCS (buf); - if (hdr_info->merge_cies) - this_inf->u.cie.u.full_cie = cie; - this_inf->u.cie.per_encoding_relative - = (cie->per_encoding & 0x70) == DW_EH_PE_pcrel; + if (!bfd_link_relocatable (info)) + { + /* Keep info for merging cies. */ + this_inf->u.cie.u.full_cie = cie; + this_inf->u.cie.per_encoding_relative + = (cie->per_encoding & 0x70) == DW_EH_PE_pcrel; + } } else { - asection *rsec; - /* Find the corresponding CIE. */ unsigned int cie_offset = this_inf->offset + 4 - hdr_id; for (cie = local_cies; cie < local_cies + cie_count; cie++) @@ -785,17 +911,23 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, = cie->cie_inf->add_augmentation_size; ENSURE_NO_RELOCS (buf); - REQUIRE (GET_RELOC (buf)); - - /* Chain together the FDEs for each section. */ - rsec = _bfd_elf_gc_mark_rsec (info, sec, gc_mark_hook, cookie); - /* RSEC will be NULL if FDE was cleared out as it was belonging to - a discarded SHT_GROUP. */ - if (rsec) + if ((sec->flags & SEC_LINKER_CREATED) == 0 || cookie->rels != NULL) { - REQUIRE (rsec->owner == abfd); - this_inf->u.fde.next_for_section = elf_fde_list (rsec); - elf_fde_list (rsec) = this_inf; + asection *rsec; + + REQUIRE (GET_RELOC (buf)); + + /* Chain together the FDEs for each section. */ + rsec = _bfd_elf_gc_mark_rsec (info, sec, gc_mark_hook, + cookie, NULL); + /* RSEC will be NULL if FDE was cleared out as it was belonging to + a discarded SHT_GROUP. */ + if (rsec) + { + REQUIRE (rsec->owner == abfd); + this_inf->u.fde.next_for_section = elf_fde_list (rsec); + elf_fde_list (rsec) = this_inf; + } } /* Skip the initial location and address range. */ @@ -803,6 +935,17 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, length = get_DW_EH_PE_width (cie->fde_encoding, ptr_size); REQUIRE (skip_bytes (&buf, end, 2 * length)); + SKIP_RELOCS (buf - length); + if (!GET_RELOC (buf - length) + && read_value (abfd, buf - length, length, FALSE) == 0) + { + (*info->callbacks->minfo) + /* xgettext:c-format */ + (_("discarding zero address range FDE in %pB(%pA).\n"), + abfd, sec); + this_inf->u.fde.cie_inf = NULL; + } + /* Skip the augmentation size, if present. */ if (cie->augmentation[0] == 'z') REQUIRE (read_uleb128 (&buf, end, &length)); @@ -869,7 +1012,7 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, bfd_byte *p; this_inf->set_loc = (unsigned int *) - bfd_malloc ((set_loc_count + 1) * sizeof (unsigned int)); + bfd_malloc ((set_loc_count + 1) * sizeof (unsigned int)); REQUIRE (this_inf->set_loc); this_inf->set_loc[0] = set_loc_count; p = insns; @@ -891,38 +1034,109 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, BFD_ASSERT (cie_count == num_cies); elf_section_data (sec)->sec_info = sec_info; - sec->sec_info_type = ELF_INFO_TYPE_EH_FRAME; - if (hdr_info->merge_cies) + sec->sec_info_type = SEC_INFO_TYPE_EH_FRAME; + if (!bfd_link_relocatable (info)) { + /* Keep info for merging cies. */ sec_info->cies = local_cies; local_cies = NULL; } goto success; free_no_table: - (*info->callbacks->einfo) - (_("%P: error in %B(%A); no .eh_frame_hdr table will be created.\n"), + _bfd_error_handler + /* xgettext:c-format */ + (_("error in %pB(%pA); no .eh_frame_hdr table will be created"), abfd, sec); - hdr_info->table = FALSE; - if (sec_info) - free (sec_info); + hdr_info->u.dwarf.table = FALSE; + free (sec_info); success: - if (ehbuf) - free (ehbuf); - if (local_cies) - free (local_cies); + free (ehbuf); + free (local_cies); #undef REQUIRE } -/* Finish a pass over all .eh_frame sections. */ +/* Order eh_frame_hdr entries by the VMA of their text section. */ -void +static int +cmp_eh_frame_hdr (const void *a, const void *b) +{ + bfd_vma text_a; + bfd_vma text_b; + asection *sec; + + sec = *(asection *const *)a; + sec = (asection *) elf_section_data (sec)->sec_info; + text_a = sec->output_section->vma + sec->output_offset; + sec = *(asection *const *)b; + sec = (asection *) elf_section_data (sec)->sec_info; + text_b = sec->output_section->vma + sec->output_offset; + + if (text_a < text_b) + return -1; + return text_a > text_b; + +} + +/* Add space for a CANTUNWIND terminator to SEC if the text sections + referenced by it and NEXT are not contiguous, or NEXT is NULL. */ + +static void +add_eh_frame_hdr_terminator (asection *sec, + asection *next) +{ + bfd_vma end; + bfd_vma next_start; + asection *text_sec; + + if (next) + { + /* See if there is a gap (presumably a text section without unwind info) + between these two entries. */ + text_sec = (asection *) elf_section_data (sec)->sec_info; + end = text_sec->output_section->vma + text_sec->output_offset + + text_sec->size; + text_sec = (asection *) elf_section_data (next)->sec_info; + next_start = text_sec->output_section->vma + text_sec->output_offset; + if (end == next_start) + return; + } + + /* Add space for a CANTUNWIND terminator. */ + if (!sec->rawsize) + sec->rawsize = sec->size; + + bfd_set_section_size (sec, sec->size + 8); +} + +/* Finish a pass over all .eh_frame_entry sections. */ + +bfd_boolean _bfd_elf_end_eh_frame_parsing (struct bfd_link_info *info) { struct eh_frame_hdr_info *hdr_info; + unsigned int i; hdr_info = &elf_hash_table (info)->eh_info; - hdr_info->parsed_eh_frames = TRUE; + + if (info->eh_frame_hdr_type != COMPACT_EH_HDR + || hdr_info->array_count == 0) + return FALSE; + + bfd_elf_discard_eh_frame_entry (hdr_info); + + qsort (hdr_info->u.compact.entries, hdr_info->array_count, + sizeof (asection *), cmp_eh_frame_hdr); + + for (i = 0; i < hdr_info->array_count - 1; i++) + { + add_eh_frame_hdr_terminator (hdr_info->u.compact.entries[i], + hdr_info->u.compact.entries[i + 1]); + } + + /* Add a CANTUNWIND terminator after the last entry. */ + add_eh_frame_hdr_terminator (hdr_info->u.compact.entries[i], NULL); + return TRUE; } /* Mark all relocations against CIE or FDE ENT, which occurs in @@ -964,7 +1178,7 @@ _bfd_elf_gc_mark_fdes (struct bfd_link_info *info, asection *sec, /* At this stage, all cie_inf fields point to local CIEs, so we can use the same cookie to refer to them. */ cie = fde->u.fde.cie_inf; - if (!cie->u.cie.gc_mark) + if (cie != NULL && !cie->u.cie.gc_mark) { cie->u.cie.gc_mark = 1; if (!mark_entry (info, eh_frame, cie, gc_mark_hook, cookie)) @@ -1014,8 +1228,12 @@ find_merged_cie (bfd *abfd, struct bfd_link_info *info, asection *sec, { bfd_boolean per_binds_local; - /* Work out the address of personality routine, either as an absolute - value or as a symbol. */ + /* Work out the address of personality routine, or at least + enough info that we could calculate the address had we made a + final section layout. The symbol on the reloc is enough, + either the hash for a global, or (bfd id, index) pair for a + local. The assumption here is that no one uses addends on + the reloc. */ rel = cookie->rels + cie->personality.reloc_index; memset (&cie->personality, 0, sizeof (cie->personality)); #ifdef BFD64 @@ -1055,14 +1273,13 @@ find_merged_cie (bfd *abfd, struct bfd_link_info *info, asection *sec, return cie_inf; cie->local_personality = 1; - cie->personality.val = (sym->st_value - + sym_sec->output_offset - + sym_sec->output_section->vma); + cie->personality.sym.bfd_id = abfd->id; + cie->personality.sym.index = r_symndx; per_binds_local = TRUE; } if (per_binds_local - && info->shared + && bfd_link_pic (info) && (cie->per_encoding & 0x70) == DW_EH_PE_absptr && (get_elf_backend_data (abfd) ->elf_backend_can_make_relative_eh_frame (abfd, info, sec))) @@ -1073,15 +1290,15 @@ find_merged_cie (bfd *abfd, struct bfd_link_info *info, asection *sec, } /* See if we can merge this CIE with an earlier one. */ - cie->output_sec = sec->output_section; cie_compute_hash (cie); - if (hdr_info->cies == NULL) + if (hdr_info->u.dwarf.cies == NULL) { - hdr_info->cies = htab_try_create (1, cie_hash, cie_eq, free); - if (hdr_info->cies == NULL) + hdr_info->u.dwarf.cies = htab_try_create (1, cie_hash, cie_eq, free); + if (hdr_info->u.dwarf.cies == NULL) return cie_inf; } - loc = htab_find_slot_with_hash (hdr_info->cies, cie, cie->hash, INSERT); + loc = htab_find_slot_with_hash (hdr_info->u.dwarf.cies, cie, + cie->hash, INSERT); if (loc == NULL) return cie_inf; @@ -1108,6 +1325,143 @@ find_merged_cie (bfd *abfd, struct bfd_link_info *info, asection *sec, return new_cie->cie_inf; } +/* For a given OFFSET in SEC, return the delta to the new location + after .eh_frame editing. */ + +static bfd_signed_vma +offset_adjust (bfd_vma offset, const asection *sec) +{ + struct eh_frame_sec_info *sec_info + = (struct eh_frame_sec_info *) elf_section_data (sec)->sec_info; + unsigned int lo, hi, mid; + struct eh_cie_fde *ent = NULL; + bfd_signed_vma delta; + + lo = 0; + hi = sec_info->count; + if (hi == 0) + return 0; + + while (lo < hi) + { + mid = (lo + hi) / 2; + ent = &sec_info->entry[mid]; + if (offset < ent->offset) + hi = mid; + else if (mid + 1 >= hi) + break; + else if (offset >= ent[1].offset) + lo = mid + 1; + else + break; + } + + if (!ent->removed) + delta = (bfd_vma) ent->new_offset - (bfd_vma) ent->offset; + else if (ent->cie && ent->u.cie.merged) + { + struct eh_cie_fde *cie = ent->u.cie.u.merged_with; + delta = ((bfd_vma) cie->new_offset + cie->u.cie.u.sec->output_offset + - (bfd_vma) ent->offset - sec->output_offset); + } + else + { + /* Is putting the symbol on the next entry best for a deleted + CIE/FDE? */ + struct eh_cie_fde *last = sec_info->entry + sec_info->count; + delta = ((bfd_vma) next_cie_fde_offset (ent, last, sec) + - (bfd_vma) ent->offset); + return delta; + } + + /* Account for editing within this CIE/FDE. */ + offset -= ent->offset; + if (ent->cie) + { + unsigned int extra + = ent->add_augmentation_size + ent->u.cie.add_fde_encoding; + if (extra == 0 + || offset <= 9u + ent->u.cie.aug_str_len) + return delta; + delta += extra; + if (offset <= 9u + ent->u.cie.aug_str_len + ent->u.cie.aug_data_len) + return delta; + delta += extra; + } + else + { + unsigned int ptr_size, width, extra = ent->add_augmentation_size; + if (offset <= 12 || extra == 0) + return delta; + ptr_size = (get_elf_backend_data (sec->owner) + ->elf_backend_eh_frame_address_size (sec->owner, sec)); + width = get_DW_EH_PE_width (ent->fde_encoding, ptr_size); + if (offset <= 8 + 2 * width) + return delta; + delta += extra; + } + + return delta; +} + +/* Adjust a global symbol defined in .eh_frame, so that it stays + relative to its original CIE/FDE. It is assumed that a symbol + defined at the beginning of a CIE/FDE belongs to that CIE/FDE + rather than marking the end of the previous CIE/FDE. This matters + when a CIE is merged with a previous CIE, since the symbol is + moved to the merged CIE. */ + +bfd_boolean +_bfd_elf_adjust_eh_frame_global_symbol (struct elf_link_hash_entry *h, + void *arg ATTRIBUTE_UNUSED) +{ + asection *sym_sec; + bfd_signed_vma delta; + + if (h->root.type != bfd_link_hash_defined + && h->root.type != bfd_link_hash_defweak) + return TRUE; + + sym_sec = h->root.u.def.section; + if (sym_sec->sec_info_type != SEC_INFO_TYPE_EH_FRAME + || elf_section_data (sym_sec)->sec_info == NULL) + return TRUE; + + delta = offset_adjust (h->root.u.def.value, sym_sec); + h->root.u.def.value += delta; + + return TRUE; +} + +/* The same for all local symbols defined in .eh_frame. Returns true + if any symbol was changed. */ + +static int +adjust_eh_frame_local_symbols (const asection *sec, + struct elf_reloc_cookie *cookie) +{ + unsigned int shndx; + Elf_Internal_Sym *sym; + Elf_Internal_Sym *end_sym; + int adjusted = 0; + + shndx = elf_section_data (sec)->this_idx; + end_sym = cookie->locsyms + cookie->locsymcount; + for (sym = cookie->locsyms + 1; sym < end_sym; ++sym) + if (sym->st_info <= ELF_ST_INFO (STB_LOCAL, STT_OBJECT) + && sym->st_shndx == shndx) + { + bfd_signed_vma delta = offset_adjust (sym->st_value, sec); + + if (delta != 0) + { + adjusted = 1; + sym->st_value += delta; + } + } + return adjusted; +} + /* 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 @@ -1122,66 +1476,133 @@ _bfd_elf_discard_section_eh_frame struct eh_cie_fde *ent; struct eh_frame_sec_info *sec_info; struct eh_frame_hdr_info *hdr_info; - unsigned int ptr_size, offset; + unsigned int ptr_size, offset, eh_alignment; + int changed; + + if (sec->sec_info_type != SEC_INFO_TYPE_EH_FRAME) + return FALSE; sec_info = (struct eh_frame_sec_info *) elf_section_data (sec)->sec_info; if (sec_info == NULL) return FALSE; + ptr_size = (get_elf_backend_data (sec->owner) + ->elf_backend_eh_frame_address_size (sec->owner, sec)); + hdr_info = &elf_hash_table (info)->eh_info; for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent) if (ent->size == 4) /* There should only be one zero terminator, on the last input file supplying .eh_frame (crtend.o). Remove any others. */ ent->removed = sec->map_head.s != NULL; - else if (!ent->cie) + else if (!ent->cie && ent->u.fde.cie_inf != NULL) { - cookie->rel = cookie->rels + ent->reloc_index; - /* FIXME: octets_per_byte. */ - BFD_ASSERT (cookie->rel < cookie->relend - && cookie->rel->r_offset == ent->offset + 8); - if (!(*reloc_symbol_deleted_p) (ent->offset + 8, cookie)) + bfd_boolean keep; + if ((sec->flags & SEC_LINKER_CREATED) != 0 && cookie->rels == NULL) { - if (info->shared + unsigned int width + = get_DW_EH_PE_width (ent->fde_encoding, ptr_size); + bfd_vma value + = read_value (abfd, sec->contents + ent->offset + 8 + width, + width, get_DW_EH_PE_signed (ent->fde_encoding)); + keep = value != 0; + } + else + { + cookie->rel = cookie->rels + ent->reloc_index; + /* FIXME: octets_per_byte. */ + BFD_ASSERT (cookie->rel < cookie->relend + && cookie->rel->r_offset == ent->offset + 8); + keep = !(*reloc_symbol_deleted_p) (ent->offset + 8, cookie); + } + if (keep) + { + if (bfd_link_pic (info) && (((ent->fde_encoding & 0x70) == DW_EH_PE_absptr && ent->make_relative == 0) || (ent->fde_encoding & 0x70) == DW_EH_PE_aligned)) { + static int num_warnings_issued = 0; + /* If a shared library uses absolute pointers which we cannot turn into PC relative, don't create the binary search table, since it is affected by runtime relocations. */ - hdr_info->table = FALSE; - (*info->callbacks->einfo) - (_("%P: fde encoding in %B(%A) prevents .eh_frame_hdr" - " table being created.\n"), abfd, sec); + hdr_info->u.dwarf.table = FALSE; + /* Only warn if --eh-frame-hdr was specified. */ + if (info->eh_frame_hdr_type != 0) + { + if (num_warnings_issued < 10) + { + _bfd_error_handler + /* xgettext:c-format */ + (_("FDE encoding in %pB(%pA) prevents .eh_frame_hdr" + " table being created"), abfd, sec); + num_warnings_issued ++; + } + else if (num_warnings_issued == 10) + { + _bfd_error_handler + (_("further warnings about FDE encoding preventing .eh_frame_hdr generation dropped")); + num_warnings_issued ++; + } + } } ent->removed = 0; - hdr_info->fde_count++; + hdr_info->u.dwarf.fde_count++; ent->u.fde.cie_inf = find_merged_cie (abfd, info, sec, hdr_info, cookie, ent->u.fde.cie_inf); } } - if (sec_info->cies) - { - free (sec_info->cies); - sec_info->cies = NULL; - } + free (sec_info->cies); + sec_info->cies = NULL; - ptr_size = (get_elf_backend_data (sec->owner) - ->elf_backend_eh_frame_address_size (sec->owner, sec)); + /* It may be that some .eh_frame input section has greater alignment + than other .eh_frame sections. In that case we run the risk of + padding with zeros before that section, which would be seen as a + zero terminator. Alignment padding must be added *inside* the + last FDE instead. For other FDEs we align according to their + encoding, in order to align FDE address range entries naturally. */ offset = 0; + changed = 0; for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent) if (!ent->removed) { + eh_alignment = 4; + if (ent->size == 4) + ; + else if (ent->cie) + { + if (ent->u.cie.per_encoding_aligned8) + eh_alignment = 8; + } + else + { + eh_alignment = get_DW_EH_PE_width (ent->fde_encoding, ptr_size); + if (eh_alignment < 4) + eh_alignment = 4; + } + offset = (offset + eh_alignment - 1) & -eh_alignment; ent->new_offset = offset; - offset += size_of_output_cie_fde (ent, ptr_size); + if (ent->new_offset != ent->offset) + changed = 1; + offset += size_of_output_cie_fde (ent); } + eh_alignment = 4; + offset = (offset + eh_alignment - 1) & -eh_alignment; sec->rawsize = sec->size; sec->size = offset; - return offset != sec->rawsize; + if (sec->size != sec->rawsize) + changed = 1; + + if (changed && adjust_eh_frame_local_symbols (sec, cookie)) + { + Elf_Internal_Shdr *symtab_hdr = &elf_tdata (abfd)->symtab_hdr; + symtab_hdr->contents = (unsigned char *) cookie->locsyms; + } + return changed; } /* This function is called for .eh_frame_hdr section after @@ -1198,24 +1619,77 @@ _bfd_elf_discard_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info) htab = elf_hash_table (info); hdr_info = &htab->eh_info; - if (hdr_info->cies != NULL) + if (!hdr_info->frame_hdr_is_compact && hdr_info->u.dwarf.cies != NULL) { - htab_delete (hdr_info->cies); - hdr_info->cies = NULL; + htab_delete (hdr_info->u.dwarf.cies); + hdr_info->u.dwarf.cies = NULL; } sec = hdr_info->hdr_sec; if (sec == NULL) return FALSE; - sec->size = EH_FRAME_HDR_SIZE; - if (hdr_info->table) - sec->size += 4 + hdr_info->fde_count * 8; + if (info->eh_frame_hdr_type == COMPACT_EH_HDR) + { + /* For compact frames we only add the header. The actual table comes + from the .eh_frame_entry sections. */ + sec->size = 8; + } + else + { + sec->size = EH_FRAME_HDR_SIZE; + if (hdr_info->u.dwarf.table) + sec->size += 4 + hdr_info->u.dwarf.fde_count * 8; + } - elf_tdata (abfd)->eh_frame_hdr = sec; + elf_eh_frame_hdr (abfd) = sec; return TRUE; } +/* Return true if there is at least one non-empty .eh_frame section in + input files. Can only be called after ld has mapped input to + output sections, and before sections are stripped. */ + +bfd_boolean +_bfd_elf_eh_frame_present (struct bfd_link_info *info) +{ + asection *eh = bfd_get_section_by_name (info->output_bfd, ".eh_frame"); + + if (eh == NULL) + return FALSE; + + /* Count only sections which have at least a single CIE or FDE. + There cannot be any CIE or FDE <= 8 bytes. */ + for (eh = eh->map_head.s; eh != NULL; eh = eh->map_head.s) + if (eh->size > 8) + return TRUE; + + return FALSE; +} + +/* Return true if there is at least one .eh_frame_entry section in + input files. */ + +bfd_boolean +_bfd_elf_eh_frame_entry_present (struct bfd_link_info *info) +{ + asection *o; + bfd *abfd; + + for (abfd = info->input_bfds; abfd != NULL; abfd = abfd->link.next) + { + for (o = abfd->sections; o; o = o->next) + { + const char *name = bfd_section_name (o); + + if (strcmp (name, ".eh_frame_entry") + && !bfd_is_abs_section (o->output_section)) + return TRUE; + } + } + return FALSE; +} + /* This function is called from size_dynamic_sections. It needs to decide whether .eh_frame_hdr should be output or not, because when the dynamic symbol table has been sized it is too late @@ -1224,41 +1698,43 @@ _bfd_elf_discard_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info) bfd_boolean _bfd_elf_maybe_strip_eh_frame_hdr (struct bfd_link_info *info) { - asection *o; - bfd *abfd; struct elf_link_hash_table *htab; struct eh_frame_hdr_info *hdr_info; + struct bfd_link_hash_entry *bh = NULL; + struct elf_link_hash_entry *h; htab = elf_hash_table (info); hdr_info = &htab->eh_info; if (hdr_info->hdr_sec == NULL) return TRUE; - if (bfd_is_abs_section (hdr_info->hdr_sec->output_section)) + if (bfd_is_abs_section (hdr_info->hdr_sec->output_section) + || info->eh_frame_hdr_type == 0 + || (info->eh_frame_hdr_type == DWARF2_EH_HDR + && !_bfd_elf_eh_frame_present (info)) + || (info->eh_frame_hdr_type == COMPACT_EH_HDR + && !_bfd_elf_eh_frame_entry_present (info))) { + hdr_info->hdr_sec->flags |= SEC_EXCLUDE; hdr_info->hdr_sec = NULL; return TRUE; } - abfd = NULL; - if (info->eh_frame_hdr) - for (abfd = info->input_bfds; abfd != NULL; abfd = abfd->link_next) - { - /* Count only sections which have at least a single CIE or FDE. - There cannot be any CIE or FDE <= 8 bytes. */ - o = bfd_get_section_by_name (abfd, ".eh_frame"); - if (o && o->size > 8 && !bfd_is_abs_section (o->output_section)) - break; - } + /* Add a hidden symbol so that systems without access to PHDRs can + find the table. */ + if (! (_bfd_generic_link_add_one_symbol + (info, info->output_bfd, "__GNU_EH_FRAME_HDR", BSF_LOCAL, + hdr_info->hdr_sec, 0, NULL, FALSE, FALSE, &bh))) + return FALSE; - if (abfd == NULL) - { - hdr_info->hdr_sec->flags |= SEC_EXCLUDE; - hdr_info->hdr_sec = NULL; - return TRUE; - } + h = (struct elf_link_hash_entry *) bh; + h->def_regular = 1; + h->other = STV_HIDDEN; + get_elf_backend_data + (info->output_bfd)->elf_backend_hide_symbol (info, h, TRUE); - hdr_info->table = TRUE; + if (!hdr_info->frame_hdr_is_compact) + hdr_info->u.dwarf.table = TRUE; return TRUE; } @@ -1269,25 +1745,20 @@ _bfd_elf_maybe_strip_eh_frame_hdr (struct bfd_link_info *info) bfd_vma _bfd_elf_eh_frame_section_offset (bfd *output_bfd ATTRIBUTE_UNUSED, - struct bfd_link_info *info, + struct bfd_link_info *info ATTRIBUTE_UNUSED, asection *sec, bfd_vma offset) { struct eh_frame_sec_info *sec_info; - struct elf_link_hash_table *htab; - struct eh_frame_hdr_info *hdr_info; unsigned int lo, hi, mid; - if (sec->sec_info_type != ELF_INFO_TYPE_EH_FRAME) + if (sec->sec_info_type != SEC_INFO_TYPE_EH_FRAME) return offset; sec_info = (struct eh_frame_sec_info *) elf_section_data (sec)->sec_info; if (offset >= sec->rawsize) return offset - sec->rawsize + sec->size; - htab = elf_hash_table (info); - hdr_info = &htab->eh_info; - lo = 0; hi = sec_info->count; mid = 0; @@ -1354,6 +1825,86 @@ _bfd_elf_eh_frame_section_offset (bfd *output_bfd ATTRIBUTE_UNUSED, + extra_augmentation_data_bytes (sec_info->entry + mid)); } +/* Write out .eh_frame_entry section. Add CANTUNWIND terminator if needed. + Also check that the contents look sane. */ + +bfd_boolean +_bfd_elf_write_section_eh_frame_entry (bfd *abfd, struct bfd_link_info *info, + asection *sec, bfd_byte *contents) +{ + const struct elf_backend_data *bed; + bfd_byte cantunwind[8]; + bfd_vma addr; + bfd_vma last_addr; + bfd_vma offset; + asection *text_sec = (asection *) elf_section_data (sec)->sec_info; + + if (!sec->rawsize) + sec->rawsize = sec->size; + + BFD_ASSERT (sec->sec_info_type == SEC_INFO_TYPE_EH_FRAME_ENTRY); + + /* Check to make sure that the text section corresponding to this eh_frame_entry + section has not been excluded. In particular, mips16 stub entries will be + excluded outside of the normal process. */ + if (sec->flags & SEC_EXCLUDE + || text_sec->flags & SEC_EXCLUDE) + return TRUE; + + if (!bfd_set_section_contents (abfd, sec->output_section, contents, + sec->output_offset, sec->rawsize)) + return FALSE; + + last_addr = bfd_get_signed_32 (abfd, contents); + /* Check that all the entries are in order. */ + for (offset = 8; offset < sec->rawsize; offset += 8) + { + addr = bfd_get_signed_32 (abfd, contents + offset) + offset; + if (addr <= last_addr) + { + /* xgettext:c-format */ + _bfd_error_handler (_("%pB: %pA not in order"), sec->owner, sec); + return FALSE; + } + + last_addr = addr; + } + + addr = text_sec->output_section->vma + text_sec->output_offset + + text_sec->size; + addr &= ~1; + addr -= (sec->output_section->vma + sec->output_offset + sec->rawsize); + if (addr & 1) + { + /* xgettext:c-format */ + _bfd_error_handler (_("%pB: %pA invalid input section size"), + sec->owner, sec); + bfd_set_error (bfd_error_bad_value); + return FALSE; + } + if (last_addr >= addr + sec->rawsize) + { + /* xgettext:c-format */ + _bfd_error_handler (_("%pB: %pA points past end of text section"), + sec->owner, sec); + bfd_set_error (bfd_error_bad_value); + return FALSE; + } + + if (sec->size == sec->rawsize) + return TRUE; + + bed = get_elf_backend_data (abfd); + BFD_ASSERT (sec->size == sec->rawsize + 8); + BFD_ASSERT ((addr & 1) == 0); + BFD_ASSERT (bed->cant_unwind_opcode); + + bfd_put_32 (abfd, addr, cantunwind); + bfd_put_32 (abfd, (*bed->cant_unwind_opcode) (info), cantunwind + 4); + return bfd_set_section_contents (abfd, sec->output_section, cantunwind, + sec->output_offset + sec->rawsize, 8); +} + /* Write out .eh_frame section. This is called with the relocated contents. */ @@ -1367,9 +1918,9 @@ _bfd_elf_write_section_eh_frame (bfd *abfd, struct elf_link_hash_table *htab; struct eh_frame_hdr_info *hdr_info; unsigned int ptr_size; - struct eh_cie_fde *ent; + struct eh_cie_fde *ent, *last_ent; - if (sec->sec_info_type != ELF_INFO_TYPE_EH_FRAME) + if (sec->sec_info_type != SEC_INFO_TYPE_EH_FRAME) /* FIXME: octets_per_byte. */ return bfd_set_section_contents (abfd, sec->output_section, contents, sec->output_offset, sec->size); @@ -1382,10 +1933,14 @@ _bfd_elf_write_section_eh_frame (bfd *abfd, htab = elf_hash_table (info); hdr_info = &htab->eh_info; - if (hdr_info->table && hdr_info->array == NULL) - hdr_info->array = (struct eh_frame_array_ent *) - bfd_malloc (hdr_info->fde_count * sizeof(*hdr_info->array)); - if (hdr_info->array == NULL) + if (hdr_info->u.dwarf.table && hdr_info->u.dwarf.array == NULL) + { + hdr_info->frame_hdr_is_compact = FALSE; + hdr_info->u.dwarf.array = (struct eh_frame_array_ent *) + bfd_malloc (hdr_info->u.dwarf.fde_count + * sizeof (*hdr_info->u.dwarf.array)); + } + if (hdr_info->u.dwarf.array == NULL) hdr_info = NULL; /* The new offsets can be bigger or smaller than the original offsets. @@ -1401,7 +1956,8 @@ _bfd_elf_write_section_eh_frame (bfd *abfd, if (!ent->removed && ent->new_offset < ent->offset) memmove (contents + ent->new_offset, contents + ent->offset, ent->size); - for (ent = sec_info->entry; ent < sec_info->entry + sec_info->count; ++ent) + last_ent = sec_info->entry + sec_info->count; + for (ent = sec_info->entry; ent < last_ent; ++ent) { unsigned char *buf, *end; unsigned int new_size; @@ -1412,13 +1968,13 @@ _bfd_elf_write_section_eh_frame (bfd *abfd, if (ent->size == 4) { /* Any terminating FDE must be at the end of the section. */ - BFD_ASSERT (ent == sec_info->entry + sec_info->count - 1); + BFD_ASSERT (ent == last_ent - 1); continue; } buf = contents + ent->new_offset; end = buf + ent->size; - new_size = size_of_output_cie_fde (ent, ptr_size); + new_size = next_cie_fde_offset (ent, last_ent, sec) - ent->new_offset; /* Update the size. It may be shrinked. */ bfd_put_32 (abfd, new_size - 4, buf); @@ -1435,7 +1991,7 @@ _bfd_elf_write_section_eh_frame (bfd *abfd, || ent->u.cie.per_encoding_relative) { char *aug; - unsigned int action, extra_string, extra_data; + unsigned int version, action, extra_string, extra_data; unsigned int per_width, per_encoding; /* Need to find 'R' or 'L' augmentation's argument and modify @@ -1446,13 +2002,17 @@ _bfd_elf_write_section_eh_frame (bfd *abfd, extra_string = extra_augmentation_string_bytes (ent); extra_data = extra_augmentation_data_bytes (ent); - /* Skip length, id and version. */ - buf += 9; + /* Skip length, id. */ + buf += 8; + version = *buf++; aug = (char *) buf; buf += strlen (aug) + 1; skip_leb128 (&buf, end); skip_leb128 (&buf, end); - skip_leb128 (&buf, end); + if (version == 1) + skip_bytes (&buf, end, 1); + else + skip_leb128 (&buf, end); if (*aug == 'z') { /* The uleb128 will always be a single byte for the kind @@ -1554,6 +2114,8 @@ _bfd_elf_write_section_eh_frame (bfd *abfd, value = ((ent->new_offset + sec->output_offset + 4) - (cie->new_offset + cie->u.cie.u.sec->output_offset)); bfd_put_32 (abfd, value, buf); + if (bfd_link_relocatable (info)) + continue; buf += 4; width = get_DW_EH_PE_width (ent->fde_encoding, ptr_size); value = read_value (abfd, buf, width, @@ -1568,10 +2130,32 @@ _bfd_elf_write_section_eh_frame (bfd *abfd, break; case DW_EH_PE_datarel: { - asection *got = bfd_get_section_by_name (abfd, ".got"); - - BFD_ASSERT (got != NULL); - address += got->vma; + switch (abfd->arch_info->arch) + { + case bfd_arch_ia64: + BFD_ASSERT (elf_gp (abfd) != 0); + address += elf_gp (abfd); + break; + default: + _bfd_error_handler + (_("DW_EH_PE_datarel unspecified" + " for this architecture")); + /* Fall thru */ + case bfd_arch_frv: + case bfd_arch_i386: + case bfd_arch_nios2: + BFD_ASSERT (htab->hgot != NULL + && ((htab->hgot->root.type + == bfd_link_hash_defined) + || (htab->hgot->root.type + == bfd_link_hash_defweak))); + address + += (htab->hgot->root.u.def.value + + htab->hgot->root.u.def.section->output_offset + + (htab->hgot->root.u.def.section->output_section + ->vma)); + break; + } } break; case DW_EH_PE_pcrel: @@ -1592,8 +2176,16 @@ _bfd_elf_write_section_eh_frame (bfd *abfd, if (hdr_info) { - hdr_info->array[hdr_info->array_count].initial_loc = address; - hdr_info->array[hdr_info->array_count++].fde + /* The address calculation may overflow, giving us a + value greater than 4G on a 32-bit target when + dwarf_vma is 64-bit. */ + if (sizeof (address) > 4 && ptr_size == 4) + address &= 0xffffffff; + hdr_info->u.dwarf.array[hdr_info->array_count].initial_loc + = address; + hdr_info->u.dwarf.array[hdr_info->array_count].range + = read_value (abfd, buf + width, width, FALSE); + hdr_info->u.dwarf.array[hdr_info->array_count++].fde = (sec->output_section->vma + sec->output_offset + ent->new_offset); @@ -1658,14 +2250,6 @@ _bfd_elf_write_section_eh_frame (bfd *abfd, } } - /* We don't align the section to its section alignment since the - runtime library only expects all CIE/FDE records aligned at - the pointer size. _bfd_elf_discard_section_eh_frame should - have padded CIE/FDE records to multiple of pointer size with - size_of_output_cie_fde. */ - if ((sec->size % ptr_size) != 0) - abort (); - /* FIXME: octets_per_byte. */ return bfd_set_section_contents (abfd, sec->output_section, contents, (file_ptr) sec->output_offset, @@ -1684,15 +2268,120 @@ vma_compare (const void *a, const void *b) return 1; if (p->initial_loc < q->initial_loc) return -1; + if (p->range > q->range) + return 1; + if (p->range < q->range) + 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: +/* Reorder .eh_frame_entry sections to match the associated text sections. + This routine is called during the final linking step, just before writing + the contents. At this stage, sections in the eh_frame_hdr_info are already + sorted in order of increasing text section address and so we simply need + to make the .eh_frame_entrys follow that same order. Note that it is + invalid for a linker script to try to force a particular order of + .eh_frame_entry sections. */ + +bfd_boolean +_bfd_elf_fixup_eh_frame_hdr (struct bfd_link_info *info) +{ + asection *sec = NULL; + asection *osec; + struct eh_frame_hdr_info *hdr_info; + unsigned int i; + bfd_vma offset; + struct bfd_link_order *p; + + hdr_info = &elf_hash_table (info)->eh_info; + + if (hdr_info->hdr_sec == NULL + || info->eh_frame_hdr_type != COMPACT_EH_HDR + || hdr_info->array_count == 0) + return TRUE; + + /* Change section output offsets to be in text section order. */ + offset = 8; + osec = hdr_info->u.compact.entries[0]->output_section; + for (i = 0; i < hdr_info->array_count; i++) + { + sec = hdr_info->u.compact.entries[i]; + if (sec->output_section != osec) + { + _bfd_error_handler + (_("invalid output section for .eh_frame_entry: %pA"), + sec->output_section); + return FALSE; + } + sec->output_offset = offset; + offset += sec->size; + } + + + /* Fix the link_order to match. */ + for (p = sec->output_section->map_head.link_order; p != NULL; p = p->next) + { + if (p->type != bfd_indirect_link_order) + abort(); + + p->offset = p->u.indirect.section->output_offset; + if (p->next != NULL) + i--; + } + + if (i != 0) + { + _bfd_error_handler + (_("invalid contents in %pA section"), osec); + return FALSE; + } + + return TRUE; +} + +/* The .eh_frame_hdr format for Compact EH frames: + ubyte version (2) + ubyte eh_ref_enc (DW_EH_PE_* encoding of typinfo references) + uint32_t count (Number of entries in table) + [array from .eh_frame_entry sections] */ + +static bfd_boolean +write_compact_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info) +{ + struct elf_link_hash_table *htab; + struct eh_frame_hdr_info *hdr_info; + asection *sec; + const struct elf_backend_data *bed; + bfd_vma count; + bfd_byte contents[8]; + unsigned int i; + + htab = elf_hash_table (info); + hdr_info = &htab->eh_info; + sec = hdr_info->hdr_sec; + + if (sec->size != 8) + abort(); + + for (i = 0; i < sizeof (contents); i++) + contents[i] = 0; + + contents[0] = COMPACT_EH_HDR; + bed = get_elf_backend_data (abfd); + + BFD_ASSERT (bed->compact_eh_encoding); + contents[1] = (*bed->compact_eh_encoding) (info); + + count = (sec->output_section->size - 8) / 8; + bfd_put_32 (abfd, count, contents + 4); + return bfd_set_section_contents (abfd, sec->output_section, contents, + (file_ptr) sec->output_offset, sec->size); +} + +/* The .eh_frame_hdr format for DWARF frames: + ubyte version (currently 1) - ubyte eh_frame_ptr_enc (DW_EH_PE_* encoding of pointer to start of + 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 @@ -1709,27 +2398,26 @@ vma_compare (const void *a, const void *b) FDE initial_location field and FDE address, sorted by increasing initial_loc). */ -bfd_boolean -_bfd_elf_write_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info) +static bfd_boolean +write_dwarf_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info) { struct elf_link_hash_table *htab; struct eh_frame_hdr_info *hdr_info; asection *sec; - bfd_byte *contents; - asection *eh_frame_sec; - bfd_size_type size; - bfd_boolean retval; - bfd_vma encoded_eh_frame; + bfd_boolean retval = TRUE; htab = elf_hash_table (info); hdr_info = &htab->eh_info; sec = hdr_info->hdr_sec; - if (sec == NULL) - return TRUE; + bfd_byte *contents; + asection *eh_frame_sec; + bfd_size_type size; + bfd_vma encoded_eh_frame; size = EH_FRAME_HDR_SIZE; - if (hdr_info->array && hdr_info->array_count == hdr_info->fde_count) - size += 4 + hdr_info->fde_count * 8; + if (hdr_info->u.dwarf.array + && hdr_info->array_count == hdr_info->u.dwarf.fde_count) + size += 4 + hdr_info->u.dwarf.fde_count * 8; contents = (bfd_byte *) bfd_malloc (size); if (contents == NULL) return FALSE; @@ -1742,15 +2430,19 @@ _bfd_elf_write_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info) } memset (contents, 0, EH_FRAME_HDR_SIZE); - contents[0] = 1; /* Version. */ + /* Version. */ + contents[0] = 1; + /* .eh_frame offset. */ contents[1] = get_elf_backend_data (abfd)->elf_backend_encode_eh_address - (abfd, info, eh_frame_sec, 0, sec, 4, - &encoded_eh_frame); /* .eh_frame offset. */ + (abfd, info, eh_frame_sec, 0, sec, 4, &encoded_eh_frame); - if (hdr_info->array && hdr_info->array_count == hdr_info->fde_count) + if (hdr_info->u.dwarf.array + && hdr_info->array_count == hdr_info->u.dwarf.fde_count) { - contents[2] = DW_EH_PE_udata4; /* FDE count encoding. */ - contents[3] = DW_EH_PE_datarel | DW_EH_PE_sdata4; /* Search table enc. */ + /* FDE count encoding. */ + contents[2] = DW_EH_PE_udata4; + /* Search table encoding. */ + contents[3] = DW_EH_PE_datarel | DW_EH_PE_sdata4; } else { @@ -1762,34 +2454,89 @@ _bfd_elf_write_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info) 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_boolean overlap, overflow; + + bfd_put_32 (abfd, hdr_info->u.dwarf.fde_count, + contents + EH_FRAME_HDR_SIZE); + qsort (hdr_info->u.dwarf.array, hdr_info->u.dwarf.fde_count, + sizeof (*hdr_info->u.dwarf.array), vma_compare); + overlap = FALSE; + overflow = FALSE; + for (i = 0; i < hdr_info->u.dwarf.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); + bfd_vma val; + + val = hdr_info->u.dwarf.array[i].initial_loc + - sec->output_section->vma; + val = ((val & 0xffffffff) ^ 0x80000000) - 0x80000000; + if (elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64 + && (hdr_info->u.dwarf.array[i].initial_loc + != sec->output_section->vma + val)) + overflow = TRUE; + bfd_put_32 (abfd, val, contents + EH_FRAME_HDR_SIZE + i * 8 + 4); + val = hdr_info->u.dwarf.array[i].fde - sec->output_section->vma; + val = ((val & 0xffffffff) ^ 0x80000000) - 0x80000000; + if (elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64 + && (hdr_info->u.dwarf.array[i].fde + != sec->output_section->vma + val)) + overflow = TRUE; + bfd_put_32 (abfd, val, contents + EH_FRAME_HDR_SIZE + i * 8 + 8); + if (i != 0 + && (hdr_info->u.dwarf.array[i].initial_loc + < (hdr_info->u.dwarf.array[i - 1].initial_loc + + hdr_info->u.dwarf.array[i - 1].range))) + overlap = TRUE; + } + if (overflow) + _bfd_error_handler (_(".eh_frame_hdr entry overflow")); + if (overlap) + _bfd_error_handler (_(".eh_frame_hdr refers to overlapping FDEs")); + if (overflow || overlap) + { + bfd_set_error (bfd_error_bad_value); + retval = FALSE; } } /* FIXME: octets_per_byte. */ - retval = bfd_set_section_contents (abfd, sec->output_section, - contents, (file_ptr) sec->output_offset, - sec->size); + if (!bfd_set_section_contents (abfd, sec->output_section, contents, + (file_ptr) sec->output_offset, + sec->size)) + retval = FALSE; free (contents); + + free (hdr_info->u.dwarf.array); return retval; } +/* 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. */ + +bfd_boolean +_bfd_elf_write_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info) +{ + struct elf_link_hash_table *htab; + struct eh_frame_hdr_info *hdr_info; + asection *sec; + + htab = elf_hash_table (info); + hdr_info = &htab->eh_info; + sec = hdr_info->hdr_sec; + + if (info->eh_frame_hdr_type == 0 || sec == NULL) + return TRUE; + + if (info->eh_frame_hdr_type == COMPACT_EH_HDR) + return write_compact_eh_frame_hdr (abfd, info); + else + return write_dwarf_eh_frame_hdr (abfd, info); +} + /* Return the width of FDE addresses. This is the default implementation. */ unsigned int -_bfd_elf_eh_frame_address_size (bfd *abfd, asection *sec ATTRIBUTE_UNUSED) +_bfd_elf_eh_frame_address_size (bfd *abfd, const asection *sec ATTRIBUTE_UNUSED) { return elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64 ? 8 : 4; }