From 04f0f42bcf4fb5f7bbde0b954f816c5f6ff7f571 Mon Sep 17 00:00:00 2001 From: Tom Tromey Date: Sat, 14 Oct 2023 13:31:57 -0600 Subject: Move read_addrmap_from_aranges to new file In the interest of shrinking dwarf2/read.c a little more, this patch moves the code that deciphers .debug_aranges into a new file. Reviewed-By: Guinevere Larsen --- gdb/Makefile.in | 2 + gdb/dwarf2/aranges.c | 200 ++++++++++++++++++++++++++++++++++++++++++ gdb/dwarf2/aranges.h | 35 ++++++++ gdb/dwarf2/read-debug-names.c | 1 + gdb/dwarf2/read.c | 179 +------------------------------------ gdb/dwarf2/read.h | 8 -- 6 files changed, 239 insertions(+), 186 deletions(-) create mode 100644 gdb/dwarf2/aranges.c create mode 100644 gdb/dwarf2/aranges.h diff --git a/gdb/Makefile.in b/gdb/Makefile.in index 9c0a0bf..52b0869 100644 --- a/gdb/Makefile.in +++ b/gdb/Makefile.in @@ -1065,6 +1065,7 @@ COMMON_SFILES = \ dwarf2/abbrev.c \ dwarf2/abbrev-cache.c \ dwarf2/ada-imported.c \ + dwarf2/aranges.c \ dwarf2/attribute.c \ dwarf2/comp-unit-head.c \ dwarf2/cooked-index.c \ @@ -1321,6 +1322,7 @@ HFILES_NO_SRCDIR = \ disasm-flags.h \ disasm.h \ dummy-frame.h \ + dwarf2/aranges.h \ dwarf2/cooked-index.h \ dwarf2/cu.h \ dwarf2/frame-tailcall.h \ diff --git a/gdb/dwarf2/aranges.c b/gdb/dwarf2/aranges.c new file mode 100644 index 0000000..06f49a4 --- /dev/null +++ b/gdb/dwarf2/aranges.c @@ -0,0 +1,200 @@ +/* DWARF aranges handling + + Copyright (C) 1994-2023 Free Software Foundation, Inc. + + This file is part of GDB. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . */ + +#include "defs.h" +#include "dwarf2/aranges.h" +#include "dwarf2/read.h" + +/* See aranges.h. */ + +bool +read_addrmap_from_aranges (dwarf2_per_objfile *per_objfile, + dwarf2_section_info *section, + addrmap *mutable_map) +{ + /* Caller must ensure that the section has already been read. */ + gdb_assert (section->readin); + if (section->empty ()) + return false; + + struct objfile *objfile = per_objfile->objfile; + bfd *abfd = objfile->obfd.get (); + struct gdbarch *gdbarch = objfile->arch (); + dwarf2_per_bfd *per_bfd = per_objfile->per_bfd; + + std::unordered_map> + debug_info_offset_to_per_cu; + for (const auto &per_cu : per_bfd->all_units) + { + /* A TU will not need aranges, and skipping them here is an easy + way of ignoring .debug_types -- and possibly seeing a + duplicate section offset -- entirely. The same applies to + units coming from a dwz file. */ + if (per_cu->is_debug_types || per_cu->is_dwz) + continue; + + const auto insertpair + = debug_info_offset_to_per_cu.emplace (per_cu->sect_off, + per_cu.get ()); + + /* Assume no duplicate offsets in all_units. */ + gdb_assert (insertpair.second); + } + + std::set debug_info_offset_seen; + const bfd_endian dwarf5_byte_order = gdbarch_byte_order (gdbarch); + const gdb_byte *addr = section->buffer; + while (addr < section->buffer + section->size) + { + const gdb_byte *const entry_addr = addr; + unsigned int bytes_read; + + const LONGEST entry_length = read_initial_length (abfd, addr, + &bytes_read); + addr += bytes_read; + + const gdb_byte *const entry_end = addr + entry_length; + const bool dwarf5_is_dwarf64 = bytes_read != 4; + const uint8_t offset_size = dwarf5_is_dwarf64 ? 8 : 4; + if (addr + entry_length > section->buffer + section->size) + { + warning (_("Section .debug_aranges in %s entry at offset %s " + "length %s exceeds section length %s, " + "ignoring .debug_aranges."), + objfile_name (objfile), + plongest (entry_addr - section->buffer), + plongest (bytes_read + entry_length), + pulongest (section->size)); + return false; + } + + /* The version number. */ + const uint16_t version = read_2_bytes (abfd, addr); + addr += 2; + if (version != 2) + { + warning (_("Section .debug_aranges in %s entry at offset %s " + "has unsupported version %d, ignoring .debug_aranges."), + objfile_name (objfile), + plongest (entry_addr - section->buffer), version); + return false; + } + + const uint64_t debug_info_offset + = extract_unsigned_integer (addr, offset_size, dwarf5_byte_order); + addr += offset_size; + const auto per_cu_it + = debug_info_offset_to_per_cu.find (sect_offset (debug_info_offset)); + if (per_cu_it == debug_info_offset_to_per_cu.cend ()) + { + warning (_("Section .debug_aranges in %s entry at offset %s " + "debug_info_offset %s does not exists, " + "ignoring .debug_aranges."), + objfile_name (objfile), + plongest (entry_addr - section->buffer), + pulongest (debug_info_offset)); + return false; + } + const auto insertpair + = debug_info_offset_seen.insert (sect_offset (debug_info_offset)); + if (!insertpair.second) + { + warning (_("Section .debug_aranges in %s has duplicate " + "debug_info_offset %s, ignoring .debug_aranges."), + objfile_name (objfile), + sect_offset_str (sect_offset (debug_info_offset))); + return false; + } + dwarf2_per_cu_data *const per_cu = per_cu_it->second; + + const uint8_t address_size = *addr++; + if (address_size < 1 || address_size > 8) + { + warning (_("Section .debug_aranges in %s entry at offset %s " + "address_size %u is invalid, ignoring .debug_aranges."), + objfile_name (objfile), + plongest (entry_addr - section->buffer), address_size); + return false; + } + + const uint8_t segment_selector_size = *addr++; + if (segment_selector_size != 0) + { + warning (_("Section .debug_aranges in %s entry at offset %s " + "segment_selector_size %u is not supported, " + "ignoring .debug_aranges."), + objfile_name (objfile), + plongest (entry_addr - section->buffer), + segment_selector_size); + return false; + } + + /* Must pad to an alignment boundary that is twice the address + size. It is undocumented by the DWARF standard but GCC does + use it. However, not every compiler does this. We can see + whether it has happened by looking at the total length of the + contents of the aranges for this CU -- it if isn't a multiple + of twice the address size, then we skip any leftover + bytes. */ + addr += (entry_end - addr) % (2 * address_size); + + while (addr < entry_end) + { + if (addr + 2 * address_size > entry_end) + { + warning (_("Section .debug_aranges in %s entry at offset %s " + "address list is not properly terminated, " + "ignoring .debug_aranges."), + objfile_name (objfile), + plongest (entry_addr - section->buffer)); + return false; + } + ULONGEST start = extract_unsigned_integer (addr, address_size, + dwarf5_byte_order); + addr += address_size; + ULONGEST length = extract_unsigned_integer (addr, address_size, + dwarf5_byte_order); + addr += address_size; + if (start == 0 && length == 0) + { + /* This can happen on some targets with --gc-sections. + This pair of values is also used to mark the end of + the entries for a given CU, but we ignore it and + instead handle termination using the check at the top + of the loop. */ + continue; + } + if (start == 0 && !per_bfd->has_section_at_zero) + { + /* Symbol was eliminated due to a COMDAT group. */ + continue; + } + ULONGEST end = start + length; + start = (ULONGEST) per_objfile->adjust ((unrelocated_addr) start); + end = (ULONGEST) per_objfile->adjust ((unrelocated_addr) end); + mutable_map->set_empty (start, end - 1, per_cu); + } + + per_cu->addresses_seen = true; + } + + return true; +} diff --git a/gdb/dwarf2/aranges.h b/gdb/dwarf2/aranges.h new file mode 100644 index 0000000..43e1cbd --- /dev/null +++ b/gdb/dwarf2/aranges.h @@ -0,0 +1,35 @@ +/* DWARF aranges handling + + Copyright (C) 1994-2023 Free Software Foundation, Inc. + + This file is part of GDB. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . */ + +#ifndef GDB_DWARF2_ARANGES_H +#define GDB_DWARF2_ARANGES_H + +class dwarf2_per_objfile; +class dwarf2_section_info; +class addrmap; + +/* Read the address map data from DWARF-5 .debug_aranges, and use it + to populate given addrmap. Returns true on success, false on + failure. */ + +extern bool read_addrmap_from_aranges (dwarf2_per_objfile *per_objfile, + dwarf2_section_info *section, + addrmap *mutable_map); + +#endif /* GDB_DWARF2_ARANGES_H */ diff --git a/gdb/dwarf2/read-debug-names.c b/gdb/dwarf2/read-debug-names.c index 89f5df6..c1b62b3 100644 --- a/gdb/dwarf2/read-debug-names.c +++ b/gdb/dwarf2/read-debug-names.c @@ -19,6 +19,7 @@ #include "defs.h" #include "read-debug-names.h" +#include "dwarf2/aranges.h" #include "complaints.h" #include "cp-support.h" diff --git a/gdb/dwarf2/read.c b/gdb/dwarf2/read.c index c8e21aa..66669e2 100644 --- a/gdb/dwarf2/read.c +++ b/gdb/dwarf2/read.c @@ -31,6 +31,7 @@ #include "defs.h" #include "dwarf2/read.h" #include "dwarf2/abbrev.h" +#include "dwarf2/aranges.h" #include "dwarf2/attribute.h" #include "dwarf2/comp-unit-head.h" #include "dwarf2/cu.h" @@ -1837,184 +1838,6 @@ create_cu_from_index_list (dwarf2_per_bfd *per_bfd, return the_cu; } -/* See read.h. */ - -bool -read_addrmap_from_aranges (dwarf2_per_objfile *per_objfile, - dwarf2_section_info *section, - addrmap *mutable_map) -{ - /* Caller must ensure that the section has already been read. */ - gdb_assert (section->readin); - if (section->empty ()) - return false; - - struct objfile *objfile = per_objfile->objfile; - bfd *abfd = objfile->obfd.get (); - struct gdbarch *gdbarch = objfile->arch (); - dwarf2_per_bfd *per_bfd = per_objfile->per_bfd; - - std::unordered_map> - debug_info_offset_to_per_cu; - for (const auto &per_cu : per_bfd->all_units) - { - /* A TU will not need aranges, and skipping them here is an easy - way of ignoring .debug_types -- and possibly seeing a - duplicate section offset -- entirely. The same applies to - units coming from a dwz file. */ - if (per_cu->is_debug_types || per_cu->is_dwz) - continue; - - const auto insertpair - = debug_info_offset_to_per_cu.emplace (per_cu->sect_off, - per_cu.get ()); - - /* Assume no duplicate offsets in all_units. */ - gdb_assert (insertpair.second); - } - - std::set debug_info_offset_seen; - const bfd_endian dwarf5_byte_order = gdbarch_byte_order (gdbarch); - const gdb_byte *addr = section->buffer; - while (addr < section->buffer + section->size) - { - const gdb_byte *const entry_addr = addr; - unsigned int bytes_read; - - const LONGEST entry_length = read_initial_length (abfd, addr, - &bytes_read); - addr += bytes_read; - - const gdb_byte *const entry_end = addr + entry_length; - const bool dwarf5_is_dwarf64 = bytes_read != 4; - const uint8_t offset_size = dwarf5_is_dwarf64 ? 8 : 4; - if (addr + entry_length > section->buffer + section->size) - { - warning (_("Section .debug_aranges in %s entry at offset %s " - "length %s exceeds section length %s, " - "ignoring .debug_aranges."), - objfile_name (objfile), - plongest (entry_addr - section->buffer), - plongest (bytes_read + entry_length), - pulongest (section->size)); - return false; - } - - /* The version number. */ - const uint16_t version = read_2_bytes (abfd, addr); - addr += 2; - if (version != 2) - { - warning (_("Section .debug_aranges in %s entry at offset %s " - "has unsupported version %d, ignoring .debug_aranges."), - objfile_name (objfile), - plongest (entry_addr - section->buffer), version); - return false; - } - - const uint64_t debug_info_offset - = extract_unsigned_integer (addr, offset_size, dwarf5_byte_order); - addr += offset_size; - const auto per_cu_it - = debug_info_offset_to_per_cu.find (sect_offset (debug_info_offset)); - if (per_cu_it == debug_info_offset_to_per_cu.cend ()) - { - warning (_("Section .debug_aranges in %s entry at offset %s " - "debug_info_offset %s does not exists, " - "ignoring .debug_aranges."), - objfile_name (objfile), - plongest (entry_addr - section->buffer), - pulongest (debug_info_offset)); - return false; - } - const auto insertpair - = debug_info_offset_seen.insert (sect_offset (debug_info_offset)); - if (!insertpair.second) - { - warning (_("Section .debug_aranges in %s has duplicate " - "debug_info_offset %s, ignoring .debug_aranges."), - objfile_name (objfile), - sect_offset_str (sect_offset (debug_info_offset))); - return false; - } - dwarf2_per_cu_data *const per_cu = per_cu_it->second; - - const uint8_t address_size = *addr++; - if (address_size < 1 || address_size > 8) - { - warning (_("Section .debug_aranges in %s entry at offset %s " - "address_size %u is invalid, ignoring .debug_aranges."), - objfile_name (objfile), - plongest (entry_addr - section->buffer), address_size); - return false; - } - - const uint8_t segment_selector_size = *addr++; - if (segment_selector_size != 0) - { - warning (_("Section .debug_aranges in %s entry at offset %s " - "segment_selector_size %u is not supported, " - "ignoring .debug_aranges."), - objfile_name (objfile), - plongest (entry_addr - section->buffer), - segment_selector_size); - return false; - } - - /* Must pad to an alignment boundary that is twice the address - size. It is undocumented by the DWARF standard but GCC does - use it. However, not every compiler does this. We can see - whether it has happened by looking at the total length of the - contents of the aranges for this CU -- it if isn't a multiple - of twice the address size, then we skip any leftover - bytes. */ - addr += (entry_end - addr) % (2 * address_size); - - while (addr < entry_end) - { - if (addr + 2 * address_size > entry_end) - { - warning (_("Section .debug_aranges in %s entry at offset %s " - "address list is not properly terminated, " - "ignoring .debug_aranges."), - objfile_name (objfile), - plongest (entry_addr - section->buffer)); - return false; - } - ULONGEST start = extract_unsigned_integer (addr, address_size, - dwarf5_byte_order); - addr += address_size; - ULONGEST length = extract_unsigned_integer (addr, address_size, - dwarf5_byte_order); - addr += address_size; - if (start == 0 && length == 0) - { - /* This can happen on some targets with --gc-sections. - This pair of values is also used to mark the end of - the entries for a given CU, but we ignore it and - instead handle termination using the check at the top - of the loop. */ - continue; - } - if (start == 0 && !per_bfd->has_section_at_zero) - { - /* Symbol was eliminated due to a COMDAT group. */ - continue; - } - ULONGEST end = start + length; - start = (ULONGEST) per_objfile->adjust ((unrelocated_addr) start); - end = (ULONGEST) per_objfile->adjust ((unrelocated_addr) end); - mutable_map->set_empty (start, end - 1, per_cu); - } - - per_cu->addresses_seen = true; - } - - return true; -} - /* die_reader_func for dw2_get_file_names. */ static void diff --git a/gdb/dwarf2/read.h b/gdb/dwarf2/read.h index dc7abf2..542b574 100644 --- a/gdb/dwarf2/read.h +++ b/gdb/dwarf2/read.h @@ -951,12 +951,4 @@ extern void finalize_all_units (dwarf2_per_bfd *per_bfd); extern htab_up create_quick_file_names_table (unsigned int nr_initial_entries); -/* Read the address map data from DWARF-5 .debug_aranges, and use it - to populate given addrmap. Returns true on success, false on - failure. */ - -extern bool read_addrmap_from_aranges (dwarf2_per_objfile *per_objfile, - dwarf2_section_info *section, - addrmap *mutable_map); - #endif /* DWARF2READ_H */ -- cgit v1.1