From 6b2cc1401c75fb337cc4092d22eac4ccf491a0a9 Mon Sep 17 00:00:00 2001 From: Richard Sandiford Date: Sat, 15 Dec 2007 09:41:15 +0000 Subject: [PATCH] bfd/ * elf-bfd.h (eh_cie_fde): Move add_fde_encoding and per_encoding_relative to u.cie. Add commentary. * elf-eh-frame.c (cie): Remove make_relative. (extra_augmentation_string_bytes): Update use of add_fde_encoding. (extra_augmentation_data_bytes): Likewise. Use an FDE's own add_augmentation_size field, rather than referring to the CIE. (_bfd_elf_parse_eh_frame): Don't set the struct cie make_relative field; set the eh_cie_fde field directly. Update setting of add_fde_encoding and per_encoding_relative. Copy make_relative and add_augmentation_size from the CIE to the FDE. (_bfd_elf_discard_section_eh_frame): Use the FDE's own make_relative field. (_bfd_elf_eh_frame_section_offset): Likewise. (_bfd_elf_write_section_eh_frame): Update accesses to add_fde_encoding and per_encoding_relative. Use the FDE's own make_relative and add_augmentation_size fields. --- bfd/ChangeLog | 20 ++++++++++++++++++++ bfd/elf-bfd.h | 25 +++++++++++++++++++++++-- bfd/elf-eh-frame.c | 55 +++++++++++++++++++++++------------------------------- 3 files changed, 66 insertions(+), 34 deletions(-) diff --git a/bfd/ChangeLog b/bfd/ChangeLog index 4f936b8..46e90c1 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,5 +1,25 @@ 2007-12-15 Richard Sandiford + * elf-bfd.h (eh_cie_fde): Move add_fde_encoding and + per_encoding_relative to u.cie. Add commentary. + * elf-eh-frame.c (cie): Remove make_relative. + (extra_augmentation_string_bytes): Update use of add_fde_encoding. + (extra_augmentation_data_bytes): Likewise. Use an FDE's own + add_augmentation_size field, rather than referring to the CIE. + (_bfd_elf_parse_eh_frame): Don't set the struct cie + make_relative field; set the eh_cie_fde field directly. + Update setting of add_fde_encoding and per_encoding_relative. + Copy make_relative and add_augmentation_size from the CIE + to the FDE. + (_bfd_elf_discard_section_eh_frame): Use the FDE's own + make_relative field. + (_bfd_elf_eh_frame_section_offset): Likewise. + (_bfd_elf_write_section_eh_frame): Update accesses to + add_fde_encoding and per_encoding_relative. Use the FDE's + own make_relative and add_augmentation_size fields. + +2007-12-15 Richard Sandiford + * elf-bfd.h (eh_cie_fde): Remove need_lsda_relative. Move make_lsda_relative to u.cie. * elf-eh-frame.c (cie): Rename make_lsda_relative to diff --git a/bfd/elf-bfd.h b/bfd/elf-bfd.h index a4e974f..4b6c1af 100644 --- a/bfd/elf-bfd.h +++ b/bfd/elf-bfd.h @@ -290,6 +290,14 @@ struct eh_cie_fde a PC-relative one. It is the group representative's setting that matters. */ unsigned int make_lsda_relative : 1; + + /* True if the CIE contains personality data and if that data + uses a PC-relative encoding. */ + unsigned int per_encoding_relative : 1; + + /* True if we need to add an 'R' (FDE encoding) entry to the + CIE's augmentation data. */ + unsigned int add_fde_encoding : 1; } cie; } u; unsigned int reloc_index; @@ -299,12 +307,25 @@ struct eh_cie_fde unsigned int fde_encoding : 8; unsigned int lsda_encoding : 8; unsigned int lsda_offset : 8; + + /* True if this entry represents a CIE, false if it represents an FDE. */ unsigned int cie : 1; + + /* True if this entry is currently marked for removal. */ unsigned int removed : 1; + + /* True if we need to add a 'z' (augmentation size) entry to the CIE's + augmentation data, and an associated byte to each of the CIE's FDEs. */ unsigned int add_augmentation_size : 1; - unsigned int add_fde_encoding : 1; + + /* True if we have decided to convert absolute FDE relocations into + relative ones. This applies to the first relocation in the FDE, + which is against the code that the FDE describes. */ unsigned int make_relative : 1; - unsigned int per_encoding_relative : 1; + + /* Unused bits. */ + unsigned int pad1 : 4; + unsigned int *set_loc; }; diff --git a/bfd/elf-eh-frame.c b/bfd/elf-eh-frame.c index 47588f4..5827a24 100644 --- a/bfd/elf-eh-frame.c +++ b/bfd/elf-eh-frame.c @@ -49,7 +49,6 @@ struct cie unsigned char lsda_encoding; unsigned char fde_encoding; unsigned char initial_insn_length; - unsigned char make_relative; unsigned char can_make_lsda_relative; unsigned char initial_instructions[50]; }; @@ -283,7 +282,7 @@ extra_augmentation_string_bytes (struct eh_cie_fde *entry) { if (entry->add_augmentation_size) size++; - if (entry->add_fde_encoding) + if (entry->u.cie.add_fde_encoding) size++; } return size; @@ -295,18 +294,10 @@ static INLINE unsigned int extra_augmentation_data_bytes (struct eh_cie_fde *entry) { unsigned int size = 0; - if (entry->cie) - { - if (entry->add_augmentation_size) - size++; - if (entry->add_fde_encoding) - size++; - } - else - { - if (entry->u.fde.cie_inf->add_augmentation_size) - size++; - } + if (entry->add_augmentation_size) + size++; + if (entry->cie && entry->u.cie.add_fde_encoding) + size++; return size; } @@ -780,7 +771,7 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, (abfd, info, sec))) { if ((cie->fde_encoding & 0xf0) == DW_EH_PE_absptr) - cie->make_relative = 1; + this_inf->make_relative = 1; /* If the CIE doesn't already have an 'R' entry, it's fairly easy to add one, provided that there's no aligned data after the augmentation string. */ @@ -789,8 +780,8 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, { if (*cie->augmentation == 0) this_inf->add_augmentation_size = 1; - this_inf->add_fde_encoding = 1; - cie->make_relative = 1; + this_inf->u.cie.add_fde_encoding = 1; + this_inf->make_relative = 1; } } @@ -816,8 +807,7 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, buf += initial_insn_length; ENSURE_NO_RELOCS (buf); - this_inf->make_relative = cie->make_relative; - this_inf->per_encoding_relative + this_inf->u.cie.per_encoding_relative = (cie->per_encoding & 0x70) == DW_EH_PE_pcrel; } else @@ -835,6 +825,9 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, REQUIRE (ecie != ecies + ecie_count); cie = ecie->cie; this_inf->u.fde.cie_inf = ecie->local_cie; + this_inf->make_relative = ecie->local_cie->make_relative; + this_inf->add_augmentation_size + = ecie->local_cie->add_augmentation_size; ENSURE_NO_RELOCS (buf); REQUIRE (GET_RELOC (buf)); @@ -900,7 +893,7 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info, } if (set_loc_count && ((cie->fde_encoding & 0xf0) == DW_EH_PE_pcrel - || cie->make_relative)) + || this_inf->make_relative)) { unsigned int cnt; bfd_byte *p; @@ -1068,7 +1061,7 @@ _bfd_elf_discard_section_eh_frame { if (info->shared && (((ent->fde_encoding & 0xf0) == DW_EH_PE_absptr - && ent->u.fde.cie_inf->make_relative == 0) + && ent->make_relative == 0) || (ent->fde_encoding & 0xf0) == DW_EH_PE_aligned)) { /* If a shared library uses absolute pointers @@ -1245,7 +1238,7 @@ _bfd_elf_eh_frame_section_offset (bfd *output_bfd ATTRIBUTE_UNUSED, /* 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].cie - && sec_info->entry[mid].u.fde.cie_inf->make_relative + && sec_info->entry[mid].make_relative && offset == sec_info->entry[mid].offset + 8) return (bfd_vma) -2; @@ -1260,9 +1253,7 @@ _bfd_elf_eh_frame_section_offset (bfd *output_bfd ATTRIBUTE_UNUSED, /* If converting to DW_EH_PE_pcrel, there will be no need for run-time relocation against DW_CFA_set_loc's arguments. */ if (sec_info->entry[mid].set_loc - && (sec_info->entry[mid].cie - ? sec_info->entry[mid].make_relative - : sec_info->entry[mid].u.fde.cie_inf->make_relative) + && sec_info->entry[mid].make_relative && (offset >= sec_info->entry[mid].offset + 8 + sec_info->entry[mid].set_loc[1])) { @@ -1394,7 +1385,7 @@ _bfd_elf_write_section_eh_frame (bfd *abfd, /* CIE */ if (ent->make_relative || ent->u.cie.make_lsda_relative - || ent->per_encoding_relative) + || ent->u.cie.per_encoding_relative) { char *aug; unsigned int action, extra_string, extra_data; @@ -1404,7 +1395,7 @@ _bfd_elf_write_section_eh_frame (bfd *abfd, DW_EH_PE_* value. */ action = ((ent->make_relative ? 1 : 0) | (ent->u.cie.make_lsda_relative ? 2 : 0) - | (ent->per_encoding_relative ? 4 : 0)); + | (ent->u.cie.per_encoding_relative ? 4 : 0)); extra_string = extra_augmentation_string_bytes (ent); extra_data = extra_augmentation_data_bytes (ent); @@ -1434,7 +1425,7 @@ _bfd_elf_write_section_eh_frame (bfd *abfd, *aug++ = 'z'; *buf++ = extra_data - 1; } - if (ent->add_fde_encoding) + if (ent->u.cie.add_fde_encoding) { BFD_ASSERT (action & 1); *aug++ = 'R'; @@ -1459,7 +1450,7 @@ _bfd_elf_write_section_eh_frame (bfd *abfd, per_width = get_DW_EH_PE_width (per_encoding, ptr_size); BFD_ASSERT (per_width != 0); BFD_ASSERT (((per_encoding & 0x70) == DW_EH_PE_pcrel) - == ent->per_encoding_relative); + == ent->u.cie.per_encoding_relative); if ((per_encoding & 0xf0) == DW_EH_PE_aligned) buf = (contents + ((buf - contents + per_width - 1) @@ -1532,7 +1523,7 @@ _bfd_elf_write_section_eh_frame (bfd *abfd, address += sec->output_section->vma + ent->offset + 8; break; } - if (cie->make_relative) + if (ent->make_relative) value -= sec->output_section->vma + ent->new_offset + 8; write_value (abfd, buf, value, width); } @@ -1563,7 +1554,7 @@ _bfd_elf_write_section_eh_frame (bfd *abfd, write_value (abfd, buf, value, width); } } - else if (cie->add_augmentation_size) + else if (ent->add_augmentation_size) { /* Skip the PC and length and insert a zero byte for the augmentation size. */ @@ -1595,7 +1586,7 @@ _bfd_elf_write_section_eh_frame (bfd *abfd, if ((ent->fde_encoding & 0xf0) == DW_EH_PE_pcrel) value += ent->offset + 8 - new_offset; - if (cie->make_relative) + if (ent->make_relative) value -= sec->output_section->vma + new_offset + ent->set_loc[cnt]; write_value (abfd, buf, value, width); -- 2.7.4