2398 lines
70 KiB
C++
2398 lines
70 KiB
C++
// dwarf_reader.cc -- parse dwarf2/3 debug information
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// Copyright 2007, 2008, 2009, 2010, 2011, 2012 Free Software Foundation, Inc.
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// Written by Ian Lance Taylor <iant@google.com>.
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// This file is part of gold.
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// This program is free software; you can redistribute it and/or modify
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// it under the terms of the GNU General Public License as published by
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// the Free Software Foundation; either version 3 of the License, or
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// (at your option) any later version.
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// This program is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU General Public License for more details.
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// You should have received a copy of the GNU General Public License
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// along with this program; if not, write to the Free Software
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// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
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// MA 02110-1301, USA.
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#include "gold.h"
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#include <algorithm>
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#include <utility>
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#include <vector>
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#include "elfcpp_swap.h"
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#include "dwarf.h"
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#include "object.h"
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#include "reloc.h"
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#include "dwarf_reader.h"
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#include "int_encoding.h"
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#include "compressed_output.h"
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namespace gold {
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// Class Sized_elf_reloc_mapper
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// Initialize the relocation tracker for section RELOC_SHNDX.
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template<int size, bool big_endian>
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bool
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Sized_elf_reloc_mapper<size, big_endian>::do_initialize(
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unsigned int reloc_shndx, unsigned int reloc_type)
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{
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this->reloc_type_ = reloc_type;
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return this->track_relocs_.initialize(this->object_, reloc_shndx,
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reloc_type);
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}
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// Looks in the symtab to see what section a symbol is in.
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template<int size, bool big_endian>
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unsigned int
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Sized_elf_reloc_mapper<size, big_endian>::symbol_section(
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unsigned int symndx, Address* value, bool* is_ordinary)
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{
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const int symsize = elfcpp::Elf_sizes<size>::sym_size;
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gold_assert(static_cast<off_t>((symndx + 1) * symsize) <= this->symtab_size_);
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elfcpp::Sym<size, big_endian> elfsym(this->symtab_ + symndx * symsize);
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*value = elfsym.get_st_value();
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return this->object_->adjust_sym_shndx(symndx, elfsym.get_st_shndx(),
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is_ordinary);
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}
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// Return the section index and offset within the section of
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// the target of the relocation for RELOC_OFFSET.
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template<int size, bool big_endian>
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unsigned int
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Sized_elf_reloc_mapper<size, big_endian>::do_get_reloc_target(
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off_t reloc_offset, off_t* target_offset)
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{
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this->track_relocs_.advance(reloc_offset);
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if (reloc_offset != this->track_relocs_.next_offset())
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return 0;
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unsigned int symndx = this->track_relocs_.next_symndx();
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typename elfcpp::Elf_types<size>::Elf_Addr value;
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bool is_ordinary;
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unsigned int target_shndx = this->symbol_section(symndx, &value,
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&is_ordinary);
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if (!is_ordinary)
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return 0;
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if (this->reloc_type_ == elfcpp::SHT_RELA)
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value += this->track_relocs_.next_addend();
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*target_offset = value;
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return target_shndx;
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}
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static inline Elf_reloc_mapper*
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make_elf_reloc_mapper(Relobj* object, const unsigned char* symtab,
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off_t symtab_size)
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{
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if (object->elfsize() == 32)
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{
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if (object->is_big_endian())
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{
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#ifdef HAVE_TARGET_32_BIG
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return new Sized_elf_reloc_mapper<32, true>(object, symtab,
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symtab_size);
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#else
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gold_unreachable();
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#endif
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}
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else
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{
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#ifdef HAVE_TARGET_32_LITTLE
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return new Sized_elf_reloc_mapper<32, false>(object, symtab,
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symtab_size);
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#else
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gold_unreachable();
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#endif
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}
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}
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else if (object->elfsize() == 64)
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{
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if (object->is_big_endian())
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{
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#ifdef HAVE_TARGET_64_BIG
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return new Sized_elf_reloc_mapper<64, true>(object, symtab,
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symtab_size);
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#else
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gold_unreachable();
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#endif
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}
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else
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{
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#ifdef HAVE_TARGET_64_LITTLE
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return new Sized_elf_reloc_mapper<64, false>(object, symtab,
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symtab_size);
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#else
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gold_unreachable();
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#endif
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}
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}
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else
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gold_unreachable();
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}
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// class Dwarf_abbrev_table
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void
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Dwarf_abbrev_table::clear_abbrev_codes()
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{
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for (unsigned int code = 0; code < this->low_abbrev_code_max_; ++code)
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{
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if (this->low_abbrev_codes_[code] != NULL)
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{
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delete this->low_abbrev_codes_[code];
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this->low_abbrev_codes_[code] = NULL;
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}
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}
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for (Abbrev_code_table::iterator it = this->high_abbrev_codes_.begin();
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it != this->high_abbrev_codes_.end();
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++it)
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{
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if (it->second != NULL)
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delete it->second;
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}
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this->high_abbrev_codes_.clear();
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}
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// Read the abbrev table from an object file.
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bool
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Dwarf_abbrev_table::do_read_abbrevs(
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Relobj* object,
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unsigned int abbrev_shndx,
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off_t abbrev_offset)
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{
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this->clear_abbrev_codes();
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// If we don't have relocations, abbrev_shndx will be 0, and
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// we'll have to hunt for the .debug_abbrev section.
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if (abbrev_shndx == 0 && this->abbrev_shndx_ > 0)
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abbrev_shndx = this->abbrev_shndx_;
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else if (abbrev_shndx == 0)
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{
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for (unsigned int i = 1; i < object->shnum(); ++i)
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{
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std::string name = object->section_name(i);
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if (name == ".debug_abbrev" || name == ".zdebug_abbrev")
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{
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abbrev_shndx = i;
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// Correct the offset. For incremental update links, we have a
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// relocated offset that is relative to the output section, but
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// here we need an offset relative to the input section.
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abbrev_offset -= object->output_section_offset(i);
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break;
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}
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}
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if (abbrev_shndx == 0)
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return false;
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}
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// Get the section contents and decompress if necessary.
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if (abbrev_shndx != this->abbrev_shndx_)
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{
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if (this->owns_buffer_ && this->buffer_ != NULL)
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{
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delete[] this->buffer_;
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this->owns_buffer_ = false;
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}
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section_size_type buffer_size;
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this->buffer_ =
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object->decompressed_section_contents(abbrev_shndx,
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&buffer_size,
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&this->owns_buffer_);
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this->buffer_end_ = this->buffer_ + buffer_size;
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this->abbrev_shndx_ = abbrev_shndx;
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}
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this->buffer_pos_ = this->buffer_ + abbrev_offset;
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return true;
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}
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// Lookup the abbrev code entry for CODE. This function is called
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// only when the abbrev code is not in the direct lookup table.
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// It may be in the hash table, it may not have been read yet,
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// or it may not exist in the abbrev table.
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const Dwarf_abbrev_table::Abbrev_code*
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Dwarf_abbrev_table::do_get_abbrev(unsigned int code)
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{
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// See if the abbrev code is already in the hash table.
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Abbrev_code_table::const_iterator it = this->high_abbrev_codes_.find(code);
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if (it != this->high_abbrev_codes_.end())
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return it->second;
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// Read and store abbrev code definitions until we find the
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// one we're looking for.
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for (;;)
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{
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// Read the abbrev code. A zero here indicates the end of the
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// abbrev table.
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size_t len;
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if (this->buffer_pos_ >= this->buffer_end_)
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return NULL;
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uint64_t nextcode = read_unsigned_LEB_128(this->buffer_pos_, &len);
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if (nextcode == 0)
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{
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this->buffer_pos_ = this->buffer_end_;
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return NULL;
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}
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this->buffer_pos_ += len;
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// Read the tag.
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if (this->buffer_pos_ >= this->buffer_end_)
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return NULL;
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uint64_t tag = read_unsigned_LEB_128(this->buffer_pos_, &len);
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this->buffer_pos_ += len;
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// Read the has_children flag.
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if (this->buffer_pos_ >= this->buffer_end_)
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return NULL;
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bool has_children = *this->buffer_pos_ == elfcpp::DW_CHILDREN_yes;
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this->buffer_pos_ += 1;
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// Read the list of (attribute, form) pairs.
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Abbrev_code* entry = new Abbrev_code(tag, has_children);
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for (;;)
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{
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// Read the attribute.
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if (this->buffer_pos_ >= this->buffer_end_)
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return NULL;
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uint64_t attr = read_unsigned_LEB_128(this->buffer_pos_, &len);
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this->buffer_pos_ += len;
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// Read the form.
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if (this->buffer_pos_ >= this->buffer_end_)
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return NULL;
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uint64_t form = read_unsigned_LEB_128(this->buffer_pos_, &len);
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this->buffer_pos_ += len;
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// A (0,0) pair terminates the list.
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if (attr == 0 && form == 0)
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break;
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if (attr == elfcpp::DW_AT_sibling)
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entry->has_sibling_attribute = true;
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entry->add_attribute(attr, form);
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}
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this->store_abbrev(nextcode, entry);
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if (nextcode == code)
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return entry;
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}
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return NULL;
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}
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// class Dwarf_ranges_table
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// Read the ranges table from an object file.
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bool
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Dwarf_ranges_table::read_ranges_table(
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Relobj* object,
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const unsigned char* symtab,
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off_t symtab_size,
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unsigned int ranges_shndx)
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{
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// If we've already read this abbrev table, return immediately.
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if (this->ranges_shndx_ > 0
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&& this->ranges_shndx_ == ranges_shndx)
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return true;
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// If we don't have relocations, ranges_shndx will be 0, and
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// we'll have to hunt for the .debug_ranges section.
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if (ranges_shndx == 0 && this->ranges_shndx_ > 0)
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ranges_shndx = this->ranges_shndx_;
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else if (ranges_shndx == 0)
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{
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for (unsigned int i = 1; i < object->shnum(); ++i)
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{
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std::string name = object->section_name(i);
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if (name == ".debug_ranges" || name == ".zdebug_ranges")
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{
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ranges_shndx = i;
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this->output_section_offset_ = object->output_section_offset(i);
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break;
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}
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}
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if (ranges_shndx == 0)
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return false;
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}
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// Get the section contents and decompress if necessary.
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if (ranges_shndx != this->ranges_shndx_)
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{
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if (this->owns_ranges_buffer_ && this->ranges_buffer_ != NULL)
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{
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delete[] this->ranges_buffer_;
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this->owns_ranges_buffer_ = false;
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}
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section_size_type buffer_size;
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this->ranges_buffer_ =
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object->decompressed_section_contents(ranges_shndx,
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&buffer_size,
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&this->owns_ranges_buffer_);
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this->ranges_buffer_end_ = this->ranges_buffer_ + buffer_size;
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this->ranges_shndx_ = ranges_shndx;
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}
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if (this->ranges_reloc_mapper_ != NULL)
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{
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delete this->ranges_reloc_mapper_;
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this->ranges_reloc_mapper_ = NULL;
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}
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// For incremental objects, we have no relocations.
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if (object->is_incremental())
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return true;
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// Find the relocation section for ".debug_ranges".
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unsigned int reloc_shndx = 0;
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unsigned int reloc_type = 0;
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for (unsigned int i = 0; i < object->shnum(); ++i)
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{
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reloc_type = object->section_type(i);
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if ((reloc_type == elfcpp::SHT_REL
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|| reloc_type == elfcpp::SHT_RELA)
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&& object->section_info(i) == ranges_shndx)
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{
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reloc_shndx = i;
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break;
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}
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}
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this->ranges_reloc_mapper_ = make_elf_reloc_mapper(object, symtab,
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symtab_size);
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this->ranges_reloc_mapper_->initialize(reloc_shndx, reloc_type);
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this->reloc_type_ = reloc_type;
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return true;
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}
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// Read a range list from section RANGES_SHNDX at offset RANGES_OFFSET.
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Dwarf_range_list*
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Dwarf_ranges_table::read_range_list(
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Relobj* object,
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const unsigned char* symtab,
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off_t symtab_size,
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unsigned int addr_size,
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unsigned int ranges_shndx,
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off_t offset)
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{
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Dwarf_range_list* ranges;
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if (!this->read_ranges_table(object, symtab, symtab_size, ranges_shndx))
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return NULL;
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// Correct the offset. For incremental update links, we have a
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// relocated offset that is relative to the output section, but
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// here we need an offset relative to the input section.
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offset -= this->output_section_offset_;
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// Read the range list at OFFSET.
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ranges = new Dwarf_range_list();
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off_t base = 0;
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for (;
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this->ranges_buffer_ + offset < this->ranges_buffer_end_;
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offset += 2 * addr_size)
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{
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off_t start;
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off_t end;
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// Read the raw contents of the section.
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if (addr_size == 4)
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{
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start = this->dwinfo_->read_from_pointer<32>(this->ranges_buffer_
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+ offset);
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end = this->dwinfo_->read_from_pointer<32>(this->ranges_buffer_
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+ offset + 4);
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}
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else
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{
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start = this->dwinfo_->read_from_pointer<64>(this->ranges_buffer_
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+ offset);
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end = this->dwinfo_->read_from_pointer<64>(this->ranges_buffer_
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+ offset + 8);
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}
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// Check for relocations and adjust the values.
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unsigned int shndx1 = 0;
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unsigned int shndx2 = 0;
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if (this->ranges_reloc_mapper_ != NULL)
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{
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shndx1 = this->lookup_reloc(offset, &start);
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shndx2 = this->lookup_reloc(offset + addr_size, &end);
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}
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// End of list is marked by a pair of zeroes.
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if (shndx1 == 0 && start == 0 && end == 0)
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break;
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// A "base address selection entry" is identified by
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// 0xffffffff for the first value of the pair. The second
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// value is used as a base for subsequent range list entries.
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if (shndx1 == 0 && start == -1)
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base = end;
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else if (shndx1 == shndx2)
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{
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if (shndx1 == 0 || object->is_section_included(shndx1))
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ranges->add(shndx1, base + start, base + end);
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}
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else
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gold_warning(_("%s: DWARF info may be corrupt; offsets in a "
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"range list entry are in different sections"),
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object->name().c_str());
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}
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return ranges;
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}
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// Look for a relocation at offset OFF in the range table,
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// and return the section index and offset of the target.
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unsigned int
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Dwarf_ranges_table::lookup_reloc(off_t off, off_t* target_off)
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{
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off_t value;
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unsigned int shndx =
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this->ranges_reloc_mapper_->get_reloc_target(off, &value);
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if (shndx == 0)
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return 0;
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if (this->reloc_type_ == elfcpp::SHT_REL)
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*target_off += value;
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else
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*target_off = value;
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return shndx;
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}
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// class Dwarf_pubnames_table
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// Read the pubnames section from the object file.
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bool
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Dwarf_pubnames_table::read_section(Relobj* object, const unsigned char* symtab,
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off_t symtab_size)
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{
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section_size_type buffer_size;
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unsigned int shndx = 0;
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const char* name = this->is_pubtypes_ ? "pubtypes" : "pubnames";
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const char* gnu_name = (this->is_pubtypes_
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? "gnu_pubtypes"
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: "gnu_pubnames");
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for (unsigned int i = 1; i < object->shnum(); ++i)
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{
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std::string section_name = object->section_name(i);
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const char* section_name_suffix = section_name.c_str();
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if (is_prefix_of(".debug_", section_name_suffix))
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section_name_suffix += 7;
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else if (is_prefix_of(".zdebug_", section_name_suffix))
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section_name_suffix += 8;
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else
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continue;
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if (strcmp(section_name_suffix, name) == 0)
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{
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shndx = i;
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this->output_section_offset_ = object->output_section_offset(i);
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break;
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}
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else if (strcmp(section_name_suffix, gnu_name) == 0)
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{
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shndx = i;
|
|
this->output_section_offset_ = object->output_section_offset(i);
|
|
this->is_gnu_style_ = true;
|
|
break;
|
|
}
|
|
}
|
|
if (shndx == 0)
|
|
return false;
|
|
|
|
this->buffer_ = object->decompressed_section_contents(shndx,
|
|
&buffer_size,
|
|
&this->owns_buffer_);
|
|
if (this->buffer_ == NULL)
|
|
return false;
|
|
this->buffer_end_ = this->buffer_ + buffer_size;
|
|
|
|
// For incremental objects, we have no relocations.
|
|
if (object->is_incremental())
|
|
return true;
|
|
|
|
// Find the relocation section
|
|
unsigned int reloc_shndx = 0;
|
|
unsigned int reloc_type = 0;
|
|
for (unsigned int i = 0; i < object->shnum(); ++i)
|
|
{
|
|
reloc_type = object->section_type(i);
|
|
if ((reloc_type == elfcpp::SHT_REL
|
|
|| reloc_type == elfcpp::SHT_RELA)
|
|
&& object->section_info(i) == shndx)
|
|
{
|
|
reloc_shndx = i;
|
|
break;
|
|
}
|
|
}
|
|
|
|
this->reloc_mapper_ = make_elf_reloc_mapper(object, symtab, symtab_size);
|
|
this->reloc_mapper_->initialize(reloc_shndx, reloc_type);
|
|
this->reloc_type_ = reloc_type;
|
|
|
|
return true;
|
|
}
|
|
|
|
// Read the header for the set at OFFSET.
|
|
|
|
bool
|
|
Dwarf_pubnames_table::read_header(off_t offset)
|
|
{
|
|
// Make sure we have actually read the section.
|
|
gold_assert(this->buffer_ != NULL);
|
|
|
|
// Correct the offset. For incremental update links, we have a
|
|
// relocated offset that is relative to the output section, but
|
|
// here we need an offset relative to the input section.
|
|
offset -= this->output_section_offset_;
|
|
|
|
if (offset < 0 || offset + 14 >= this->buffer_end_ - this->buffer_)
|
|
return false;
|
|
|
|
const unsigned char* pinfo = this->buffer_ + offset;
|
|
|
|
// Read the unit_length field.
|
|
uint64_t unit_length = this->dwinfo_->read_from_pointer<32>(pinfo);
|
|
pinfo += 4;
|
|
if (unit_length == 0xffffffff)
|
|
{
|
|
unit_length = this->dwinfo_->read_from_pointer<64>(pinfo);
|
|
this->unit_length_ = unit_length + 12;
|
|
pinfo += 8;
|
|
this->offset_size_ = 8;
|
|
}
|
|
else
|
|
{
|
|
this->unit_length_ = unit_length + 4;
|
|
this->offset_size_ = 4;
|
|
}
|
|
this->end_of_table_ = pinfo + unit_length;
|
|
|
|
// Check the version.
|
|
unsigned int version = this->dwinfo_->read_from_pointer<16>(pinfo);
|
|
pinfo += 2;
|
|
if (version != 2)
|
|
return false;
|
|
|
|
this->reloc_mapper_->get_reloc_target(pinfo - this->buffer_,
|
|
&this->cu_offset_);
|
|
|
|
// Skip the debug_info_offset and debug_info_size fields.
|
|
pinfo += 2 * this->offset_size_;
|
|
|
|
if (pinfo >= this->buffer_end_)
|
|
return false;
|
|
|
|
this->pinfo_ = pinfo;
|
|
return true;
|
|
}
|
|
|
|
// Read the next name from the set.
|
|
|
|
const char*
|
|
Dwarf_pubnames_table::next_name(uint8_t* flag_byte)
|
|
{
|
|
const unsigned char* pinfo = this->pinfo_;
|
|
|
|
// Check for end of list. The table should be terminated by an
|
|
// entry containing nothing but a DIE offset of 0.
|
|
if (pinfo + this->offset_size_ >= this->end_of_table_)
|
|
return NULL;
|
|
|
|
// Skip the offset within the CU. If this is zero, but we're not
|
|
// at the end of the table, then we have a real pubnames entry
|
|
// whose DIE offset is 0 (likely to be a GCC bug). Since we
|
|
// don't actually use the DIE offset in building .gdb_index,
|
|
// it's harmless.
|
|
pinfo += this->offset_size_;
|
|
|
|
if (this->is_gnu_style_)
|
|
*flag_byte = *pinfo++;
|
|
else
|
|
*flag_byte = 0;
|
|
|
|
// Return a pointer to the string at the current location,
|
|
// and advance the pointer to the next entry.
|
|
const char* ret = reinterpret_cast<const char*>(pinfo);
|
|
while (pinfo < this->buffer_end_ && *pinfo != '\0')
|
|
++pinfo;
|
|
if (pinfo < this->buffer_end_)
|
|
++pinfo;
|
|
|
|
this->pinfo_ = pinfo;
|
|
return ret;
|
|
}
|
|
|
|
// class Dwarf_die
|
|
|
|
Dwarf_die::Dwarf_die(
|
|
Dwarf_info_reader* dwinfo,
|
|
off_t die_offset,
|
|
Dwarf_die* parent)
|
|
: dwinfo_(dwinfo), parent_(parent), die_offset_(die_offset),
|
|
child_offset_(0), sibling_offset_(0), abbrev_code_(NULL), attributes_(),
|
|
attributes_read_(false), name_(NULL), name_off_(-1), linkage_name_(NULL),
|
|
linkage_name_off_(-1), string_shndx_(0), specification_(0),
|
|
abstract_origin_(0)
|
|
{
|
|
size_t len;
|
|
const unsigned char* pdie = dwinfo->buffer_at_offset(die_offset);
|
|
if (pdie == NULL)
|
|
return;
|
|
unsigned int code = read_unsigned_LEB_128(pdie, &len);
|
|
if (code == 0)
|
|
{
|
|
if (parent != NULL)
|
|
parent->set_sibling_offset(die_offset + len);
|
|
return;
|
|
}
|
|
this->attr_offset_ = len;
|
|
|
|
// Lookup the abbrev code in the abbrev table.
|
|
this->abbrev_code_ = dwinfo->get_abbrev(code);
|
|
}
|
|
|
|
// Read all the attributes of the DIE.
|
|
|
|
bool
|
|
Dwarf_die::read_attributes()
|
|
{
|
|
if (this->attributes_read_)
|
|
return true;
|
|
|
|
gold_assert(this->abbrev_code_ != NULL);
|
|
|
|
const unsigned char* pdie =
|
|
this->dwinfo_->buffer_at_offset(this->die_offset_);
|
|
if (pdie == NULL)
|
|
return false;
|
|
const unsigned char* pattr = pdie + this->attr_offset_;
|
|
|
|
unsigned int nattr = this->abbrev_code_->attributes.size();
|
|
this->attributes_.reserve(nattr);
|
|
for (unsigned int i = 0; i < nattr; ++i)
|
|
{
|
|
size_t len;
|
|
unsigned int attr = this->abbrev_code_->attributes[i].attr;
|
|
unsigned int form = this->abbrev_code_->attributes[i].form;
|
|
if (form == elfcpp::DW_FORM_indirect)
|
|
{
|
|
form = read_unsigned_LEB_128(pattr, &len);
|
|
pattr += len;
|
|
}
|
|
off_t attr_off = this->die_offset_ + (pattr - pdie);
|
|
bool ref_form = false;
|
|
Attribute_value attr_value;
|
|
attr_value.attr = attr;
|
|
attr_value.form = form;
|
|
attr_value.aux.shndx = 0;
|
|
switch(form)
|
|
{
|
|
case elfcpp::DW_FORM_flag_present:
|
|
attr_value.val.intval = 1;
|
|
break;
|
|
case elfcpp::DW_FORM_strp:
|
|
{
|
|
off_t str_off;
|
|
if (this->dwinfo_->offset_size() == 4)
|
|
str_off = this->dwinfo_->read_from_pointer<32>(&pattr);
|
|
else
|
|
str_off = this->dwinfo_->read_from_pointer<64>(&pattr);
|
|
unsigned int shndx =
|
|
this->dwinfo_->lookup_reloc(attr_off, &str_off);
|
|
attr_value.aux.shndx = shndx;
|
|
attr_value.val.refval = str_off;
|
|
break;
|
|
}
|
|
case elfcpp::DW_FORM_sec_offset:
|
|
{
|
|
off_t sec_off;
|
|
if (this->dwinfo_->offset_size() == 4)
|
|
sec_off = this->dwinfo_->read_from_pointer<32>(&pattr);
|
|
else
|
|
sec_off = this->dwinfo_->read_from_pointer<64>(&pattr);
|
|
unsigned int shndx =
|
|
this->dwinfo_->lookup_reloc(attr_off, &sec_off);
|
|
attr_value.aux.shndx = shndx;
|
|
attr_value.val.refval = sec_off;
|
|
ref_form = true;
|
|
break;
|
|
}
|
|
case elfcpp::DW_FORM_addr:
|
|
case elfcpp::DW_FORM_ref_addr:
|
|
{
|
|
off_t sec_off;
|
|
if (this->dwinfo_->address_size() == 4)
|
|
sec_off = this->dwinfo_->read_from_pointer<32>(&pattr);
|
|
else
|
|
sec_off = this->dwinfo_->read_from_pointer<64>(&pattr);
|
|
unsigned int shndx =
|
|
this->dwinfo_->lookup_reloc(attr_off, &sec_off);
|
|
attr_value.aux.shndx = shndx;
|
|
attr_value.val.refval = sec_off;
|
|
ref_form = true;
|
|
break;
|
|
}
|
|
case elfcpp::DW_FORM_block1:
|
|
attr_value.aux.blocklen = *pattr++;
|
|
attr_value.val.blockval = pattr;
|
|
pattr += attr_value.aux.blocklen;
|
|
break;
|
|
case elfcpp::DW_FORM_block2:
|
|
attr_value.aux.blocklen =
|
|
this->dwinfo_->read_from_pointer<16>(&pattr);
|
|
attr_value.val.blockval = pattr;
|
|
pattr += attr_value.aux.blocklen;
|
|
break;
|
|
case elfcpp::DW_FORM_block4:
|
|
attr_value.aux.blocklen =
|
|
this->dwinfo_->read_from_pointer<32>(&pattr);
|
|
attr_value.val.blockval = pattr;
|
|
pattr += attr_value.aux.blocklen;
|
|
break;
|
|
case elfcpp::DW_FORM_block:
|
|
case elfcpp::DW_FORM_exprloc:
|
|
attr_value.aux.blocklen = read_unsigned_LEB_128(pattr, &len);
|
|
attr_value.val.blockval = pattr + len;
|
|
pattr += len + attr_value.aux.blocklen;
|
|
break;
|
|
case elfcpp::DW_FORM_data1:
|
|
case elfcpp::DW_FORM_flag:
|
|
attr_value.val.intval = *pattr++;
|
|
break;
|
|
case elfcpp::DW_FORM_ref1:
|
|
attr_value.val.refval = *pattr++;
|
|
ref_form = true;
|
|
break;
|
|
case elfcpp::DW_FORM_data2:
|
|
attr_value.val.intval =
|
|
this->dwinfo_->read_from_pointer<16>(&pattr);
|
|
break;
|
|
case elfcpp::DW_FORM_ref2:
|
|
attr_value.val.refval =
|
|
this->dwinfo_->read_from_pointer<16>(&pattr);
|
|
ref_form = true;
|
|
break;
|
|
case elfcpp::DW_FORM_data4:
|
|
{
|
|
off_t sec_off;
|
|
sec_off = this->dwinfo_->read_from_pointer<32>(&pattr);
|
|
unsigned int shndx =
|
|
this->dwinfo_->lookup_reloc(attr_off, &sec_off);
|
|
attr_value.aux.shndx = shndx;
|
|
attr_value.val.intval = sec_off;
|
|
break;
|
|
}
|
|
case elfcpp::DW_FORM_ref4:
|
|
{
|
|
off_t sec_off;
|
|
sec_off = this->dwinfo_->read_from_pointer<32>(&pattr);
|
|
unsigned int shndx =
|
|
this->dwinfo_->lookup_reloc(attr_off, &sec_off);
|
|
attr_value.aux.shndx = shndx;
|
|
attr_value.val.refval = sec_off;
|
|
ref_form = true;
|
|
break;
|
|
}
|
|
case elfcpp::DW_FORM_data8:
|
|
{
|
|
off_t sec_off;
|
|
sec_off = this->dwinfo_->read_from_pointer<64>(&pattr);
|
|
unsigned int shndx =
|
|
this->dwinfo_->lookup_reloc(attr_off, &sec_off);
|
|
attr_value.aux.shndx = shndx;
|
|
attr_value.val.intval = sec_off;
|
|
break;
|
|
}
|
|
case elfcpp::DW_FORM_ref_sig8:
|
|
attr_value.val.uintval =
|
|
this->dwinfo_->read_from_pointer<64>(&pattr);
|
|
break;
|
|
case elfcpp::DW_FORM_ref8:
|
|
{
|
|
off_t sec_off;
|
|
sec_off = this->dwinfo_->read_from_pointer<64>(&pattr);
|
|
unsigned int shndx =
|
|
this->dwinfo_->lookup_reloc(attr_off, &sec_off);
|
|
attr_value.aux.shndx = shndx;
|
|
attr_value.val.refval = sec_off;
|
|
ref_form = true;
|
|
break;
|
|
}
|
|
case elfcpp::DW_FORM_ref_udata:
|
|
attr_value.val.refval = read_unsigned_LEB_128(pattr, &len);
|
|
ref_form = true;
|
|
pattr += len;
|
|
break;
|
|
case elfcpp::DW_FORM_udata:
|
|
case elfcpp::DW_FORM_GNU_addr_index:
|
|
case elfcpp::DW_FORM_GNU_str_index:
|
|
attr_value.val.uintval = read_unsigned_LEB_128(pattr, &len);
|
|
pattr += len;
|
|
break;
|
|
case elfcpp::DW_FORM_sdata:
|
|
attr_value.val.intval = read_signed_LEB_128(pattr, &len);
|
|
pattr += len;
|
|
break;
|
|
case elfcpp::DW_FORM_string:
|
|
attr_value.val.stringval = reinterpret_cast<const char*>(pattr);
|
|
len = strlen(attr_value.val.stringval);
|
|
pattr += len + 1;
|
|
break;
|
|
default:
|
|
return false;
|
|
}
|
|
|
|
// Cache the most frequently-requested attributes.
|
|
switch (attr)
|
|
{
|
|
case elfcpp::DW_AT_name:
|
|
if (form == elfcpp::DW_FORM_string)
|
|
this->name_ = attr_value.val.stringval;
|
|
else if (form == elfcpp::DW_FORM_strp)
|
|
{
|
|
// All indirect strings should refer to the same
|
|
// string section, so we just save the last one seen.
|
|
this->string_shndx_ = attr_value.aux.shndx;
|
|
this->name_off_ = attr_value.val.refval;
|
|
}
|
|
break;
|
|
case elfcpp::DW_AT_linkage_name:
|
|
case elfcpp::DW_AT_MIPS_linkage_name:
|
|
if (form == elfcpp::DW_FORM_string)
|
|
this->linkage_name_ = attr_value.val.stringval;
|
|
else if (form == elfcpp::DW_FORM_strp)
|
|
{
|
|
// All indirect strings should refer to the same
|
|
// string section, so we just save the last one seen.
|
|
this->string_shndx_ = attr_value.aux.shndx;
|
|
this->linkage_name_off_ = attr_value.val.refval;
|
|
}
|
|
break;
|
|
case elfcpp::DW_AT_specification:
|
|
if (ref_form)
|
|
this->specification_ = attr_value.val.refval;
|
|
break;
|
|
case elfcpp::DW_AT_abstract_origin:
|
|
if (ref_form)
|
|
this->abstract_origin_ = attr_value.val.refval;
|
|
break;
|
|
case elfcpp::DW_AT_sibling:
|
|
if (ref_form && attr_value.aux.shndx == 0)
|
|
this->sibling_offset_ = attr_value.val.refval;
|
|
default:
|
|
break;
|
|
}
|
|
|
|
this->attributes_.push_back(attr_value);
|
|
}
|
|
|
|
// Now that we know where the next DIE begins, record the offset
|
|
// to avoid later recalculation.
|
|
if (this->has_children())
|
|
this->child_offset_ = this->die_offset_ + (pattr - pdie);
|
|
else
|
|
this->sibling_offset_ = this->die_offset_ + (pattr - pdie);
|
|
|
|
this->attributes_read_ = true;
|
|
return true;
|
|
}
|
|
|
|
// Skip all the attributes of the DIE and return the offset of the next DIE.
|
|
|
|
off_t
|
|
Dwarf_die::skip_attributes()
|
|
{
|
|
gold_assert(this->abbrev_code_ != NULL);
|
|
|
|
const unsigned char* pdie =
|
|
this->dwinfo_->buffer_at_offset(this->die_offset_);
|
|
if (pdie == NULL)
|
|
return 0;
|
|
const unsigned char* pattr = pdie + this->attr_offset_;
|
|
|
|
for (unsigned int i = 0; i < this->abbrev_code_->attributes.size(); ++i)
|
|
{
|
|
size_t len;
|
|
unsigned int form = this->abbrev_code_->attributes[i].form;
|
|
if (form == elfcpp::DW_FORM_indirect)
|
|
{
|
|
form = read_unsigned_LEB_128(pattr, &len);
|
|
pattr += len;
|
|
}
|
|
switch(form)
|
|
{
|
|
case elfcpp::DW_FORM_flag_present:
|
|
break;
|
|
case elfcpp::DW_FORM_strp:
|
|
case elfcpp::DW_FORM_sec_offset:
|
|
pattr += this->dwinfo_->offset_size();
|
|
break;
|
|
case elfcpp::DW_FORM_addr:
|
|
case elfcpp::DW_FORM_ref_addr:
|
|
pattr += this->dwinfo_->address_size();
|
|
break;
|
|
case elfcpp::DW_FORM_block1:
|
|
pattr += 1 + *pattr;
|
|
break;
|
|
case elfcpp::DW_FORM_block2:
|
|
{
|
|
uint16_t block_size;
|
|
block_size = this->dwinfo_->read_from_pointer<16>(&pattr);
|
|
pattr += block_size;
|
|
break;
|
|
}
|
|
case elfcpp::DW_FORM_block4:
|
|
{
|
|
uint32_t block_size;
|
|
block_size = this->dwinfo_->read_from_pointer<32>(&pattr);
|
|
pattr += block_size;
|
|
break;
|
|
}
|
|
case elfcpp::DW_FORM_block:
|
|
case elfcpp::DW_FORM_exprloc:
|
|
{
|
|
uint64_t block_size;
|
|
block_size = read_unsigned_LEB_128(pattr, &len);
|
|
pattr += len + block_size;
|
|
break;
|
|
}
|
|
case elfcpp::DW_FORM_data1:
|
|
case elfcpp::DW_FORM_ref1:
|
|
case elfcpp::DW_FORM_flag:
|
|
pattr += 1;
|
|
break;
|
|
case elfcpp::DW_FORM_data2:
|
|
case elfcpp::DW_FORM_ref2:
|
|
pattr += 2;
|
|
break;
|
|
case elfcpp::DW_FORM_data4:
|
|
case elfcpp::DW_FORM_ref4:
|
|
pattr += 4;
|
|
break;
|
|
case elfcpp::DW_FORM_data8:
|
|
case elfcpp::DW_FORM_ref8:
|
|
case elfcpp::DW_FORM_ref_sig8:
|
|
pattr += 8;
|
|
break;
|
|
case elfcpp::DW_FORM_ref_udata:
|
|
case elfcpp::DW_FORM_udata:
|
|
case elfcpp::DW_FORM_GNU_addr_index:
|
|
case elfcpp::DW_FORM_GNU_str_index:
|
|
read_unsigned_LEB_128(pattr, &len);
|
|
pattr += len;
|
|
break;
|
|
case elfcpp::DW_FORM_sdata:
|
|
read_signed_LEB_128(pattr, &len);
|
|
pattr += len;
|
|
break;
|
|
case elfcpp::DW_FORM_string:
|
|
len = strlen(reinterpret_cast<const char*>(pattr));
|
|
pattr += len + 1;
|
|
break;
|
|
default:
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
return this->die_offset_ + (pattr - pdie);
|
|
}
|
|
|
|
// Get the name of the DIE and cache it.
|
|
|
|
void
|
|
Dwarf_die::set_name()
|
|
{
|
|
if (this->name_ != NULL || !this->read_attributes())
|
|
return;
|
|
if (this->name_off_ != -1)
|
|
this->name_ = this->dwinfo_->get_string(this->name_off_,
|
|
this->string_shndx_);
|
|
}
|
|
|
|
// Get the linkage name of the DIE and cache it.
|
|
|
|
void
|
|
Dwarf_die::set_linkage_name()
|
|
{
|
|
if (this->linkage_name_ != NULL || !this->read_attributes())
|
|
return;
|
|
if (this->linkage_name_off_ != -1)
|
|
this->linkage_name_ = this->dwinfo_->get_string(this->linkage_name_off_,
|
|
this->string_shndx_);
|
|
}
|
|
|
|
// Return the value of attribute ATTR.
|
|
|
|
const Dwarf_die::Attribute_value*
|
|
Dwarf_die::attribute(unsigned int attr)
|
|
{
|
|
if (!this->read_attributes())
|
|
return NULL;
|
|
for (unsigned int i = 0; i < this->attributes_.size(); ++i)
|
|
{
|
|
if (this->attributes_[i].attr == attr)
|
|
return &this->attributes_[i];
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
const char*
|
|
Dwarf_die::string_attribute(unsigned int attr)
|
|
{
|
|
const Attribute_value* attr_val = this->attribute(attr);
|
|
if (attr_val == NULL)
|
|
return NULL;
|
|
switch (attr_val->form)
|
|
{
|
|
case elfcpp::DW_FORM_string:
|
|
return attr_val->val.stringval;
|
|
case elfcpp::DW_FORM_strp:
|
|
return this->dwinfo_->get_string(attr_val->val.refval,
|
|
attr_val->aux.shndx);
|
|
default:
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
int64_t
|
|
Dwarf_die::int_attribute(unsigned int attr)
|
|
{
|
|
const Attribute_value* attr_val = this->attribute(attr);
|
|
if (attr_val == NULL)
|
|
return 0;
|
|
switch (attr_val->form)
|
|
{
|
|
case elfcpp::DW_FORM_flag_present:
|
|
case elfcpp::DW_FORM_data1:
|
|
case elfcpp::DW_FORM_flag:
|
|
case elfcpp::DW_FORM_data2:
|
|
case elfcpp::DW_FORM_data4:
|
|
case elfcpp::DW_FORM_data8:
|
|
case elfcpp::DW_FORM_sdata:
|
|
return attr_val->val.intval;
|
|
default:
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
uint64_t
|
|
Dwarf_die::uint_attribute(unsigned int attr)
|
|
{
|
|
const Attribute_value* attr_val = this->attribute(attr);
|
|
if (attr_val == NULL)
|
|
return 0;
|
|
switch (attr_val->form)
|
|
{
|
|
case elfcpp::DW_FORM_flag_present:
|
|
case elfcpp::DW_FORM_data1:
|
|
case elfcpp::DW_FORM_flag:
|
|
case elfcpp::DW_FORM_data4:
|
|
case elfcpp::DW_FORM_data8:
|
|
case elfcpp::DW_FORM_ref_sig8:
|
|
case elfcpp::DW_FORM_udata:
|
|
return attr_val->val.uintval;
|
|
default:
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
off_t
|
|
Dwarf_die::ref_attribute(unsigned int attr, unsigned int* shndx)
|
|
{
|
|
const Attribute_value* attr_val = this->attribute(attr);
|
|
if (attr_val == NULL)
|
|
return -1;
|
|
switch (attr_val->form)
|
|
{
|
|
case elfcpp::DW_FORM_sec_offset:
|
|
case elfcpp::DW_FORM_addr:
|
|
case elfcpp::DW_FORM_ref_addr:
|
|
case elfcpp::DW_FORM_ref1:
|
|
case elfcpp::DW_FORM_ref2:
|
|
case elfcpp::DW_FORM_ref4:
|
|
case elfcpp::DW_FORM_ref8:
|
|
case elfcpp::DW_FORM_ref_udata:
|
|
*shndx = attr_val->aux.shndx;
|
|
return attr_val->val.refval;
|
|
case elfcpp::DW_FORM_ref_sig8:
|
|
*shndx = attr_val->aux.shndx;
|
|
return attr_val->val.uintval;
|
|
case elfcpp::DW_FORM_data4:
|
|
case elfcpp::DW_FORM_data8:
|
|
*shndx = attr_val->aux.shndx;
|
|
return attr_val->val.intval;
|
|
default:
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
off_t
|
|
Dwarf_die::address_attribute(unsigned int attr, unsigned int* shndx)
|
|
{
|
|
const Attribute_value* attr_val = this->attribute(attr);
|
|
if (attr_val == NULL || attr_val->form != elfcpp::DW_FORM_addr)
|
|
return -1;
|
|
|
|
*shndx = attr_val->aux.shndx;
|
|
return attr_val->val.refval;
|
|
}
|
|
|
|
// Return the offset of this DIE's first child.
|
|
|
|
off_t
|
|
Dwarf_die::child_offset()
|
|
{
|
|
gold_assert(this->abbrev_code_ != NULL);
|
|
if (!this->has_children())
|
|
return 0;
|
|
if (this->child_offset_ == 0)
|
|
this->child_offset_ = this->skip_attributes();
|
|
return this->child_offset_;
|
|
}
|
|
|
|
// Return the offset of this DIE's next sibling.
|
|
|
|
off_t
|
|
Dwarf_die::sibling_offset()
|
|
{
|
|
gold_assert(this->abbrev_code_ != NULL);
|
|
|
|
if (this->sibling_offset_ != 0)
|
|
return this->sibling_offset_;
|
|
|
|
if (!this->has_children())
|
|
{
|
|
this->sibling_offset_ = this->skip_attributes();
|
|
return this->sibling_offset_;
|
|
}
|
|
|
|
if (this->has_sibling_attribute())
|
|
{
|
|
if (!this->read_attributes())
|
|
return 0;
|
|
if (this->sibling_offset_ != 0)
|
|
return this->sibling_offset_;
|
|
}
|
|
|
|
// Skip over the children.
|
|
off_t child_offset = this->child_offset();
|
|
while (child_offset > 0)
|
|
{
|
|
Dwarf_die die(this->dwinfo_, child_offset, this);
|
|
// The Dwarf_die ctor will set this DIE's sibling offset
|
|
// when it reads a zero abbrev code.
|
|
if (die.tag() == 0)
|
|
break;
|
|
child_offset = die.sibling_offset();
|
|
}
|
|
|
|
// This should be set by now. If not, there was a problem reading
|
|
// the DWARF info, and we return 0.
|
|
return this->sibling_offset_;
|
|
}
|
|
|
|
// class Dwarf_info_reader
|
|
|
|
// Begin parsing the debug info. This calls visit_compilation_unit()
|
|
// or visit_type_unit() for each compilation or type unit found in the
|
|
// section, and visit_die() for each top-level DIE.
|
|
|
|
void
|
|
Dwarf_info_reader::parse()
|
|
{
|
|
if (this->object_->is_big_endian())
|
|
{
|
|
#if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
|
|
this->do_parse<true>();
|
|
#else
|
|
gold_unreachable();
|
|
#endif
|
|
}
|
|
else
|
|
{
|
|
#if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
|
|
this->do_parse<false>();
|
|
#else
|
|
gold_unreachable();
|
|
#endif
|
|
}
|
|
}
|
|
|
|
template<bool big_endian>
|
|
void
|
|
Dwarf_info_reader::do_parse()
|
|
{
|
|
// Get the section contents and decompress if necessary.
|
|
section_size_type buffer_size;
|
|
bool buffer_is_new;
|
|
this->buffer_ = this->object_->decompressed_section_contents(this->shndx_,
|
|
&buffer_size,
|
|
&buffer_is_new);
|
|
if (this->buffer_ == NULL || buffer_size == 0)
|
|
return;
|
|
this->buffer_end_ = this->buffer_ + buffer_size;
|
|
|
|
// The offset of this input section in the output section.
|
|
off_t section_offset = this->object_->output_section_offset(this->shndx_);
|
|
|
|
// Start tracking relocations for this section.
|
|
this->reloc_mapper_ = make_elf_reloc_mapper(this->object_, this->symtab_,
|
|
this->symtab_size_);
|
|
this->reloc_mapper_->initialize(this->reloc_shndx_, this->reloc_type_);
|
|
|
|
// Loop over compilation units (or type units).
|
|
unsigned int abbrev_shndx = this->abbrev_shndx_;
|
|
off_t abbrev_offset = 0;
|
|
const unsigned char* pinfo = this->buffer_;
|
|
while (pinfo < this->buffer_end_)
|
|
{
|
|
// Read the compilation (or type) unit header.
|
|
const unsigned char* cu_start = pinfo;
|
|
this->cu_offset_ = cu_start - this->buffer_;
|
|
this->cu_length_ = this->buffer_end_ - cu_start;
|
|
|
|
// Read unit_length (4 or 12 bytes).
|
|
if (!this->check_buffer(pinfo + 4))
|
|
break;
|
|
uint32_t unit_length =
|
|
elfcpp::Swap_unaligned<32, big_endian>::readval(pinfo);
|
|
pinfo += 4;
|
|
if (unit_length == 0xffffffff)
|
|
{
|
|
if (!this->check_buffer(pinfo + 8))
|
|
break;
|
|
unit_length = elfcpp::Swap_unaligned<64, big_endian>::readval(pinfo);
|
|
pinfo += 8;
|
|
this->offset_size_ = 8;
|
|
}
|
|
else
|
|
this->offset_size_ = 4;
|
|
if (!this->check_buffer(pinfo + unit_length))
|
|
break;
|
|
const unsigned char* cu_end = pinfo + unit_length;
|
|
this->cu_length_ = cu_end - cu_start;
|
|
if (!this->check_buffer(pinfo + 2 + this->offset_size_ + 1))
|
|
break;
|
|
|
|
// Read version (2 bytes).
|
|
this->cu_version_ =
|
|
elfcpp::Swap_unaligned<16, big_endian>::readval(pinfo);
|
|
pinfo += 2;
|
|
|
|
// Read debug_abbrev_offset (4 or 8 bytes).
|
|
if (this->offset_size_ == 4)
|
|
abbrev_offset = elfcpp::Swap_unaligned<32, big_endian>::readval(pinfo);
|
|
else
|
|
abbrev_offset = elfcpp::Swap_unaligned<64, big_endian>::readval(pinfo);
|
|
if (this->reloc_shndx_ > 0)
|
|
{
|
|
off_t reloc_offset = pinfo - this->buffer_;
|
|
off_t value;
|
|
abbrev_shndx =
|
|
this->reloc_mapper_->get_reloc_target(reloc_offset, &value);
|
|
if (abbrev_shndx == 0)
|
|
return;
|
|
if (this->reloc_type_ == elfcpp::SHT_REL)
|
|
abbrev_offset += value;
|
|
else
|
|
abbrev_offset = value;
|
|
}
|
|
pinfo += this->offset_size_;
|
|
|
|
// Read address_size (1 byte).
|
|
this->address_size_ = *pinfo++;
|
|
|
|
// For type units, read the two extra fields.
|
|
uint64_t signature = 0;
|
|
off_t type_offset = 0;
|
|
if (this->is_type_unit_)
|
|
{
|
|
if (!this->check_buffer(pinfo + 8 + this->offset_size_))
|
|
break;
|
|
|
|
// Read type_signature (8 bytes).
|
|
signature = elfcpp::Swap_unaligned<64, big_endian>::readval(pinfo);
|
|
pinfo += 8;
|
|
|
|
// Read type_offset (4 or 8 bytes).
|
|
if (this->offset_size_ == 4)
|
|
type_offset =
|
|
elfcpp::Swap_unaligned<32, big_endian>::readval(pinfo);
|
|
else
|
|
type_offset =
|
|
elfcpp::Swap_unaligned<64, big_endian>::readval(pinfo);
|
|
pinfo += this->offset_size_;
|
|
}
|
|
|
|
// Read the .debug_abbrev table.
|
|
this->abbrev_table_.read_abbrevs(this->object_, abbrev_shndx,
|
|
abbrev_offset);
|
|
|
|
// Visit the root DIE.
|
|
Dwarf_die root_die(this,
|
|
pinfo - (this->buffer_ + this->cu_offset_),
|
|
NULL);
|
|
if (root_die.tag() != 0)
|
|
{
|
|
// Visit the CU or TU.
|
|
if (this->is_type_unit_)
|
|
this->visit_type_unit(section_offset + this->cu_offset_,
|
|
cu_end - cu_start, type_offset, signature,
|
|
&root_die);
|
|
else
|
|
this->visit_compilation_unit(section_offset + this->cu_offset_,
|
|
cu_end - cu_start, &root_die);
|
|
}
|
|
|
|
// Advance to the next CU.
|
|
pinfo = cu_end;
|
|
}
|
|
|
|
if (buffer_is_new)
|
|
{
|
|
delete[] this->buffer_;
|
|
this->buffer_ = NULL;
|
|
}
|
|
}
|
|
|
|
// Read the DWARF string table.
|
|
|
|
bool
|
|
Dwarf_info_reader::do_read_string_table(unsigned int string_shndx)
|
|
{
|
|
Relobj* object = this->object_;
|
|
|
|
// If we don't have relocations, string_shndx will be 0, and
|
|
// we'll have to hunt for the .debug_str section.
|
|
if (string_shndx == 0)
|
|
{
|
|
for (unsigned int i = 1; i < this->object_->shnum(); ++i)
|
|
{
|
|
std::string name = object->section_name(i);
|
|
if (name == ".debug_str" || name == ".zdebug_str")
|
|
{
|
|
string_shndx = i;
|
|
this->string_output_section_offset_ =
|
|
object->output_section_offset(i);
|
|
break;
|
|
}
|
|
}
|
|
if (string_shndx == 0)
|
|
return false;
|
|
}
|
|
|
|
if (this->owns_string_buffer_ && this->string_buffer_ != NULL)
|
|
{
|
|
delete[] this->string_buffer_;
|
|
this->owns_string_buffer_ = false;
|
|
}
|
|
|
|
// Get the secton contents and decompress if necessary.
|
|
section_size_type buffer_size;
|
|
const unsigned char* buffer =
|
|
object->decompressed_section_contents(string_shndx,
|
|
&buffer_size,
|
|
&this->owns_string_buffer_);
|
|
this->string_buffer_ = reinterpret_cast<const char*>(buffer);
|
|
this->string_buffer_end_ = this->string_buffer_ + buffer_size;
|
|
this->string_shndx_ = string_shndx;
|
|
return true;
|
|
}
|
|
|
|
// Read a possibly unaligned integer of SIZE.
|
|
template <int valsize>
|
|
inline typename elfcpp::Valtype_base<valsize>::Valtype
|
|
Dwarf_info_reader::read_from_pointer(const unsigned char* source)
|
|
{
|
|
typename elfcpp::Valtype_base<valsize>::Valtype return_value;
|
|
if (this->object_->is_big_endian())
|
|
return_value = elfcpp::Swap_unaligned<valsize, true>::readval(source);
|
|
else
|
|
return_value = elfcpp::Swap_unaligned<valsize, false>::readval(source);
|
|
return return_value;
|
|
}
|
|
|
|
// Read a possibly unaligned integer of SIZE. Update SOURCE after read.
|
|
template <int valsize>
|
|
inline typename elfcpp::Valtype_base<valsize>::Valtype
|
|
Dwarf_info_reader::read_from_pointer(const unsigned char** source)
|
|
{
|
|
typename elfcpp::Valtype_base<valsize>::Valtype return_value;
|
|
if (this->object_->is_big_endian())
|
|
return_value = elfcpp::Swap_unaligned<valsize, true>::readval(*source);
|
|
else
|
|
return_value = elfcpp::Swap_unaligned<valsize, false>::readval(*source);
|
|
*source += valsize / 8;
|
|
return return_value;
|
|
}
|
|
|
|
// Look for a relocation at offset ATTR_OFF in the dwarf info,
|
|
// and return the section index and offset of the target.
|
|
|
|
unsigned int
|
|
Dwarf_info_reader::lookup_reloc(off_t attr_off, off_t* target_off)
|
|
{
|
|
off_t value;
|
|
attr_off += this->cu_offset_;
|
|
unsigned int shndx = this->reloc_mapper_->get_reloc_target(attr_off, &value);
|
|
if (shndx == 0)
|
|
return 0;
|
|
if (this->reloc_type_ == elfcpp::SHT_REL)
|
|
*target_off += value;
|
|
else
|
|
*target_off = value;
|
|
return shndx;
|
|
}
|
|
|
|
// Return a string from the DWARF string table.
|
|
|
|
const char*
|
|
Dwarf_info_reader::get_string(off_t str_off, unsigned int string_shndx)
|
|
{
|
|
if (!this->read_string_table(string_shndx))
|
|
return NULL;
|
|
|
|
// Correct the offset. For incremental update links, we have a
|
|
// relocated offset that is relative to the output section, but
|
|
// here we need an offset relative to the input section.
|
|
str_off -= this->string_output_section_offset_;
|
|
|
|
const char* p = this->string_buffer_ + str_off;
|
|
|
|
if (p < this->string_buffer_ || p >= this->string_buffer_end_)
|
|
return NULL;
|
|
|
|
return p;
|
|
}
|
|
|
|
// The following are default, do-nothing, implementations of the
|
|
// hook methods normally provided by a derived class. We provide
|
|
// default implementations rather than no implementation so that
|
|
// a derived class needs to implement only the hooks that it needs
|
|
// to use.
|
|
|
|
// Process a compilation unit and parse its child DIE.
|
|
|
|
void
|
|
Dwarf_info_reader::visit_compilation_unit(off_t, off_t, Dwarf_die*)
|
|
{
|
|
}
|
|
|
|
// Process a type unit and parse its child DIE.
|
|
|
|
void
|
|
Dwarf_info_reader::visit_type_unit(off_t, off_t, off_t, uint64_t, Dwarf_die*)
|
|
{
|
|
}
|
|
|
|
// Print a warning about a corrupt debug section.
|
|
|
|
void
|
|
Dwarf_info_reader::warn_corrupt_debug_section() const
|
|
{
|
|
gold_warning(_("%s: corrupt debug info in %s"),
|
|
this->object_->name().c_str(),
|
|
this->object_->section_name(this->shndx_).c_str());
|
|
}
|
|
|
|
// class Sized_dwarf_line_info
|
|
|
|
struct LineStateMachine
|
|
{
|
|
int file_num;
|
|
uint64_t address;
|
|
int line_num;
|
|
int column_num;
|
|
unsigned int shndx; // the section address refers to
|
|
bool is_stmt; // stmt means statement.
|
|
bool basic_block;
|
|
bool end_sequence;
|
|
};
|
|
|
|
static void
|
|
ResetLineStateMachine(struct LineStateMachine* lsm, bool default_is_stmt)
|
|
{
|
|
lsm->file_num = 1;
|
|
lsm->address = 0;
|
|
lsm->line_num = 1;
|
|
lsm->column_num = 0;
|
|
lsm->shndx = -1U;
|
|
lsm->is_stmt = default_is_stmt;
|
|
lsm->basic_block = false;
|
|
lsm->end_sequence = false;
|
|
}
|
|
|
|
template<int size, bool big_endian>
|
|
Sized_dwarf_line_info<size, big_endian>::Sized_dwarf_line_info(
|
|
Object* object,
|
|
unsigned int read_shndx)
|
|
: data_valid_(false), buffer_(NULL), buffer_start_(NULL),
|
|
reloc_mapper_(NULL), symtab_buffer_(NULL), directories_(), files_(),
|
|
current_header_index_(-1)
|
|
{
|
|
unsigned int debug_shndx;
|
|
|
|
for (debug_shndx = 1; debug_shndx < object->shnum(); ++debug_shndx)
|
|
{
|
|
// FIXME: do this more efficiently: section_name() isn't super-fast
|
|
std::string name = object->section_name(debug_shndx);
|
|
if (name == ".debug_line" || name == ".zdebug_line")
|
|
{
|
|
section_size_type buffer_size;
|
|
bool is_new = false;
|
|
this->buffer_ = object->decompressed_section_contents(debug_shndx,
|
|
&buffer_size,
|
|
&is_new);
|
|
if (is_new)
|
|
this->buffer_start_ = this->buffer_;
|
|
this->buffer_end_ = this->buffer_ + buffer_size;
|
|
break;
|
|
}
|
|
}
|
|
if (this->buffer_ == NULL)
|
|
return;
|
|
|
|
// Find the relocation section for ".debug_line".
|
|
// We expect these for relobjs (.o's) but not dynobjs (.so's).
|
|
unsigned int reloc_shndx = 0;
|
|
for (unsigned int i = 0; i < object->shnum(); ++i)
|
|
{
|
|
unsigned int reloc_sh_type = object->section_type(i);
|
|
if ((reloc_sh_type == elfcpp::SHT_REL
|
|
|| reloc_sh_type == elfcpp::SHT_RELA)
|
|
&& object->section_info(i) == debug_shndx)
|
|
{
|
|
reloc_shndx = i;
|
|
this->track_relocs_type_ = reloc_sh_type;
|
|
break;
|
|
}
|
|
}
|
|
|
|
// Finally, we need the symtab section to interpret the relocs.
|
|
if (reloc_shndx != 0)
|
|
{
|
|
unsigned int symtab_shndx;
|
|
for (symtab_shndx = 0; symtab_shndx < object->shnum(); ++symtab_shndx)
|
|
if (object->section_type(symtab_shndx) == elfcpp::SHT_SYMTAB)
|
|
{
|
|
this->symtab_buffer_ = object->section_contents(
|
|
symtab_shndx, &this->symtab_buffer_size_, false);
|
|
break;
|
|
}
|
|
if (this->symtab_buffer_ == NULL)
|
|
return;
|
|
}
|
|
|
|
this->reloc_mapper_ =
|
|
new Sized_elf_reloc_mapper<size, big_endian>(object,
|
|
this->symtab_buffer_,
|
|
this->symtab_buffer_size_);
|
|
if (!this->reloc_mapper_->initialize(reloc_shndx, this->track_relocs_type_))
|
|
return;
|
|
|
|
// Now that we have successfully read all the data, parse the debug
|
|
// info.
|
|
this->data_valid_ = true;
|
|
this->read_line_mappings(read_shndx);
|
|
}
|
|
|
|
// Read the DWARF header.
|
|
|
|
template<int size, bool big_endian>
|
|
const unsigned char*
|
|
Sized_dwarf_line_info<size, big_endian>::read_header_prolog(
|
|
const unsigned char* lineptr)
|
|
{
|
|
uint32_t initial_length = elfcpp::Swap_unaligned<32, big_endian>::readval(lineptr);
|
|
lineptr += 4;
|
|
|
|
// In DWARF2/3, if the initial length is all 1 bits, then the offset
|
|
// size is 8 and we need to read the next 8 bytes for the real length.
|
|
if (initial_length == 0xffffffff)
|
|
{
|
|
header_.offset_size = 8;
|
|
initial_length = elfcpp::Swap_unaligned<64, big_endian>::readval(lineptr);
|
|
lineptr += 8;
|
|
}
|
|
else
|
|
header_.offset_size = 4;
|
|
|
|
header_.total_length = initial_length;
|
|
|
|
gold_assert(lineptr + header_.total_length <= buffer_end_);
|
|
|
|
header_.version = elfcpp::Swap_unaligned<16, big_endian>::readval(lineptr);
|
|
lineptr += 2;
|
|
|
|
if (header_.offset_size == 4)
|
|
header_.prologue_length = elfcpp::Swap_unaligned<32, big_endian>::readval(lineptr);
|
|
else
|
|
header_.prologue_length = elfcpp::Swap_unaligned<64, big_endian>::readval(lineptr);
|
|
lineptr += header_.offset_size;
|
|
|
|
header_.min_insn_length = *lineptr;
|
|
lineptr += 1;
|
|
|
|
header_.default_is_stmt = *lineptr;
|
|
lineptr += 1;
|
|
|
|
header_.line_base = *reinterpret_cast<const signed char*>(lineptr);
|
|
lineptr += 1;
|
|
|
|
header_.line_range = *lineptr;
|
|
lineptr += 1;
|
|
|
|
header_.opcode_base = *lineptr;
|
|
lineptr += 1;
|
|
|
|
header_.std_opcode_lengths.resize(header_.opcode_base + 1);
|
|
header_.std_opcode_lengths[0] = 0;
|
|
for (int i = 1; i < header_.opcode_base; i++)
|
|
{
|
|
header_.std_opcode_lengths[i] = *lineptr;
|
|
lineptr += 1;
|
|
}
|
|
|
|
return lineptr;
|
|
}
|
|
|
|
// The header for a debug_line section is mildly complicated, because
|
|
// the line info is very tightly encoded.
|
|
|
|
template<int size, bool big_endian>
|
|
const unsigned char*
|
|
Sized_dwarf_line_info<size, big_endian>::read_header_tables(
|
|
const unsigned char* lineptr)
|
|
{
|
|
++this->current_header_index_;
|
|
|
|
// Create a new directories_ entry and a new files_ entry for our new
|
|
// header. We initialize each with a single empty element, because
|
|
// dwarf indexes directory and filenames starting at 1.
|
|
gold_assert(static_cast<int>(this->directories_.size())
|
|
== this->current_header_index_);
|
|
gold_assert(static_cast<int>(this->files_.size())
|
|
== this->current_header_index_);
|
|
this->directories_.push_back(std::vector<std::string>(1));
|
|
this->files_.push_back(std::vector<std::pair<int, std::string> >(1));
|
|
|
|
// It is legal for the directory entry table to be empty.
|
|
if (*lineptr)
|
|
{
|
|
int dirindex = 1;
|
|
while (*lineptr)
|
|
{
|
|
const char* dirname = reinterpret_cast<const char*>(lineptr);
|
|
gold_assert(dirindex
|
|
== static_cast<int>(this->directories_.back().size()));
|
|
this->directories_.back().push_back(dirname);
|
|
lineptr += this->directories_.back().back().size() + 1;
|
|
dirindex++;
|
|
}
|
|
}
|
|
lineptr++;
|
|
|
|
// It is also legal for the file entry table to be empty.
|
|
if (*lineptr)
|
|
{
|
|
int fileindex = 1;
|
|
size_t len;
|
|
while (*lineptr)
|
|
{
|
|
const char* filename = reinterpret_cast<const char*>(lineptr);
|
|
lineptr += strlen(filename) + 1;
|
|
|
|
uint64_t dirindex = read_unsigned_LEB_128(lineptr, &len);
|
|
lineptr += len;
|
|
|
|
if (dirindex >= this->directories_.back().size())
|
|
dirindex = 0;
|
|
int dirindexi = static_cast<int>(dirindex);
|
|
|
|
read_unsigned_LEB_128(lineptr, &len); // mod_time
|
|
lineptr += len;
|
|
|
|
read_unsigned_LEB_128(lineptr, &len); // filelength
|
|
lineptr += len;
|
|
|
|
gold_assert(fileindex
|
|
== static_cast<int>(this->files_.back().size()));
|
|
this->files_.back().push_back(std::make_pair(dirindexi, filename));
|
|
fileindex++;
|
|
}
|
|
}
|
|
lineptr++;
|
|
|
|
return lineptr;
|
|
}
|
|
|
|
// Process a single opcode in the .debug.line structure.
|
|
|
|
template<int size, bool big_endian>
|
|
bool
|
|
Sized_dwarf_line_info<size, big_endian>::process_one_opcode(
|
|
const unsigned char* start, struct LineStateMachine* lsm, size_t* len)
|
|
{
|
|
size_t oplen = 0;
|
|
size_t templen;
|
|
unsigned char opcode = *start;
|
|
oplen++;
|
|
start++;
|
|
|
|
// If the opcode is great than the opcode_base, it is a special
|
|
// opcode. Most line programs consist mainly of special opcodes.
|
|
if (opcode >= header_.opcode_base)
|
|
{
|
|
opcode -= header_.opcode_base;
|
|
const int advance_address = ((opcode / header_.line_range)
|
|
* header_.min_insn_length);
|
|
lsm->address += advance_address;
|
|
|
|
const int advance_line = ((opcode % header_.line_range)
|
|
+ header_.line_base);
|
|
lsm->line_num += advance_line;
|
|
lsm->basic_block = true;
|
|
*len = oplen;
|
|
return true;
|
|
}
|
|
|
|
// Otherwise, we have the regular opcodes
|
|
switch (opcode)
|
|
{
|
|
case elfcpp::DW_LNS_copy:
|
|
lsm->basic_block = false;
|
|
*len = oplen;
|
|
return true;
|
|
|
|
case elfcpp::DW_LNS_advance_pc:
|
|
{
|
|
const uint64_t advance_address
|
|
= read_unsigned_LEB_128(start, &templen);
|
|
oplen += templen;
|
|
lsm->address += header_.min_insn_length * advance_address;
|
|
}
|
|
break;
|
|
|
|
case elfcpp::DW_LNS_advance_line:
|
|
{
|
|
const uint64_t advance_line = read_signed_LEB_128(start, &templen);
|
|
oplen += templen;
|
|
lsm->line_num += advance_line;
|
|
}
|
|
break;
|
|
|
|
case elfcpp::DW_LNS_set_file:
|
|
{
|
|
const uint64_t fileno = read_unsigned_LEB_128(start, &templen);
|
|
oplen += templen;
|
|
lsm->file_num = fileno;
|
|
}
|
|
break;
|
|
|
|
case elfcpp::DW_LNS_set_column:
|
|
{
|
|
const uint64_t colno = read_unsigned_LEB_128(start, &templen);
|
|
oplen += templen;
|
|
lsm->column_num = colno;
|
|
}
|
|
break;
|
|
|
|
case elfcpp::DW_LNS_negate_stmt:
|
|
lsm->is_stmt = !lsm->is_stmt;
|
|
break;
|
|
|
|
case elfcpp::DW_LNS_set_basic_block:
|
|
lsm->basic_block = true;
|
|
break;
|
|
|
|
case elfcpp::DW_LNS_fixed_advance_pc:
|
|
{
|
|
int advance_address;
|
|
advance_address = elfcpp::Swap_unaligned<16, big_endian>::readval(start);
|
|
oplen += 2;
|
|
lsm->address += advance_address;
|
|
}
|
|
break;
|
|
|
|
case elfcpp::DW_LNS_const_add_pc:
|
|
{
|
|
const int advance_address = (header_.min_insn_length
|
|
* ((255 - header_.opcode_base)
|
|
/ header_.line_range));
|
|
lsm->address += advance_address;
|
|
}
|
|
break;
|
|
|
|
case elfcpp::DW_LNS_extended_op:
|
|
{
|
|
const uint64_t extended_op_len
|
|
= read_unsigned_LEB_128(start, &templen);
|
|
start += templen;
|
|
oplen += templen + extended_op_len;
|
|
|
|
const unsigned char extended_op = *start;
|
|
start++;
|
|
|
|
switch (extended_op)
|
|
{
|
|
case elfcpp::DW_LNE_end_sequence:
|
|
// This means that the current byte is the one immediately
|
|
// after a set of instructions. Record the current line
|
|
// for up to one less than the current address.
|
|
lsm->line_num = -1;
|
|
lsm->end_sequence = true;
|
|
*len = oplen;
|
|
return true;
|
|
|
|
case elfcpp::DW_LNE_set_address:
|
|
{
|
|
lsm->address =
|
|
elfcpp::Swap_unaligned<size, big_endian>::readval(start);
|
|
typename Reloc_map::const_iterator it
|
|
= this->reloc_map_.find(start - this->buffer_);
|
|
if (it != reloc_map_.end())
|
|
{
|
|
// If this is a SHT_RELA section, then ignore the
|
|
// section contents. This assumes that this is a
|
|
// straight reloc which just uses the reloc addend.
|
|
// The reloc addend has already been included in the
|
|
// symbol value.
|
|
if (this->track_relocs_type_ == elfcpp::SHT_RELA)
|
|
lsm->address = 0;
|
|
// Add in the symbol value.
|
|
lsm->address += it->second.second;
|
|
lsm->shndx = it->second.first;
|
|
}
|
|
else
|
|
{
|
|
// If we're a normal .o file, with relocs, every
|
|
// set_address should have an associated relocation.
|
|
if (this->input_is_relobj())
|
|
this->data_valid_ = false;
|
|
}
|
|
break;
|
|
}
|
|
case elfcpp::DW_LNE_define_file:
|
|
{
|
|
const char* filename = reinterpret_cast<const char*>(start);
|
|
templen = strlen(filename) + 1;
|
|
start += templen;
|
|
|
|
uint64_t dirindex = read_unsigned_LEB_128(start, &templen);
|
|
|
|
if (dirindex >= this->directories_.back().size())
|
|
dirindex = 0;
|
|
int dirindexi = static_cast<int>(dirindex);
|
|
|
|
// This opcode takes two additional ULEB128 parameters
|
|
// (mod_time and filelength), but we don't use those
|
|
// values. Because OPLEN already tells us how far to
|
|
// skip to the next opcode, we don't need to read
|
|
// them at all.
|
|
|
|
this->files_.back().push_back(std::make_pair(dirindexi,
|
|
filename));
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
break;
|
|
|
|
default:
|
|
{
|
|
// Ignore unknown opcode silently
|
|
for (int i = 0; i < header_.std_opcode_lengths[opcode]; i++)
|
|
{
|
|
size_t templen;
|
|
read_unsigned_LEB_128(start, &templen);
|
|
start += templen;
|
|
oplen += templen;
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
*len = oplen;
|
|
return false;
|
|
}
|
|
|
|
// Read the debug information at LINEPTR and store it in the line
|
|
// number map.
|
|
|
|
template<int size, bool big_endian>
|
|
unsigned const char*
|
|
Sized_dwarf_line_info<size, big_endian>::read_lines(unsigned const char* lineptr,
|
|
unsigned int shndx)
|
|
{
|
|
struct LineStateMachine lsm;
|
|
|
|
// LENGTHSTART is the place the length field is based on. It is the
|
|
// point in the header after the initial length field.
|
|
const unsigned char* lengthstart = buffer_;
|
|
|
|
// In 64 bit dwarf, the initial length is 12 bytes, because of the
|
|
// 0xffffffff at the start.
|
|
if (header_.offset_size == 8)
|
|
lengthstart += 12;
|
|
else
|
|
lengthstart += 4;
|
|
|
|
while (lineptr < lengthstart + header_.total_length)
|
|
{
|
|
ResetLineStateMachine(&lsm, header_.default_is_stmt);
|
|
while (!lsm.end_sequence)
|
|
{
|
|
size_t oplength;
|
|
bool add_line = this->process_one_opcode(lineptr, &lsm, &oplength);
|
|
if (add_line
|
|
&& (shndx == -1U || lsm.shndx == -1U || shndx == lsm.shndx))
|
|
{
|
|
Offset_to_lineno_entry entry
|
|
= { static_cast<off_t>(lsm.address),
|
|
this->current_header_index_,
|
|
static_cast<unsigned int>(lsm.file_num),
|
|
true, lsm.line_num };
|
|
std::vector<Offset_to_lineno_entry>&
|
|
map(this->line_number_map_[lsm.shndx]);
|
|
// If we see two consecutive entries with the same
|
|
// offset and a real line number, then mark the first
|
|
// one as non-canonical.
|
|
if (!map.empty()
|
|
&& (map.back().offset == static_cast<off_t>(lsm.address))
|
|
&& lsm.line_num != -1
|
|
&& map.back().line_num != -1)
|
|
map.back().last_line_for_offset = false;
|
|
map.push_back(entry);
|
|
}
|
|
lineptr += oplength;
|
|
}
|
|
}
|
|
|
|
return lengthstart + header_.total_length;
|
|
}
|
|
|
|
// Read the relocations into a Reloc_map.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_dwarf_line_info<size, big_endian>::read_relocs()
|
|
{
|
|
if (this->symtab_buffer_ == NULL)
|
|
return;
|
|
|
|
off_t value;
|
|
off_t reloc_offset;
|
|
while ((reloc_offset = this->reloc_mapper_->next_offset()) != -1)
|
|
{
|
|
const unsigned int shndx =
|
|
this->reloc_mapper_->get_reloc_target(reloc_offset, &value);
|
|
|
|
// There is no reason to record non-ordinary section indexes, or
|
|
// SHN_UNDEF, because they will never match the real section.
|
|
if (shndx != 0)
|
|
this->reloc_map_[reloc_offset] = std::make_pair(shndx, value);
|
|
|
|
this->reloc_mapper_->advance(reloc_offset + 1);
|
|
}
|
|
}
|
|
|
|
// Read the line number info.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_dwarf_line_info<size, big_endian>::read_line_mappings(unsigned int shndx)
|
|
{
|
|
gold_assert(this->data_valid_ == true);
|
|
|
|
this->read_relocs();
|
|
while (this->buffer_ < this->buffer_end_)
|
|
{
|
|
const unsigned char* lineptr = this->buffer_;
|
|
lineptr = this->read_header_prolog(lineptr);
|
|
lineptr = this->read_header_tables(lineptr);
|
|
lineptr = this->read_lines(lineptr, shndx);
|
|
this->buffer_ = lineptr;
|
|
}
|
|
|
|
// Sort the lines numbers, so addr2line can use binary search.
|
|
for (typename Lineno_map::iterator it = line_number_map_.begin();
|
|
it != line_number_map_.end();
|
|
++it)
|
|
// Each vector needs to be sorted by offset.
|
|
std::sort(it->second.begin(), it->second.end());
|
|
}
|
|
|
|
// Some processing depends on whether the input is a .o file or not.
|
|
// For instance, .o files have relocs, and have .debug_lines
|
|
// information on a per section basis. .so files, on the other hand,
|
|
// lack relocs, and offsets are unique, so we can ignore the section
|
|
// information.
|
|
|
|
template<int size, bool big_endian>
|
|
bool
|
|
Sized_dwarf_line_info<size, big_endian>::input_is_relobj()
|
|
{
|
|
// Only .o files have relocs and the symtab buffer that goes with them.
|
|
return this->symtab_buffer_ != NULL;
|
|
}
|
|
|
|
// Given an Offset_to_lineno_entry vector, and an offset, figure out
|
|
// if the offset points into a function according to the vector (see
|
|
// comments below for the algorithm). If it does, return an iterator
|
|
// into the vector that points to the line-number that contains that
|
|
// offset. If not, it returns vector::end().
|
|
|
|
static std::vector<Offset_to_lineno_entry>::const_iterator
|
|
offset_to_iterator(const std::vector<Offset_to_lineno_entry>* offsets,
|
|
off_t offset)
|
|
{
|
|
const Offset_to_lineno_entry lookup_key = { offset, 0, 0, true, 0 };
|
|
|
|
// lower_bound() returns the smallest offset which is >= lookup_key.
|
|
// If no offset in offsets is >= lookup_key, returns end().
|
|
std::vector<Offset_to_lineno_entry>::const_iterator it
|
|
= std::lower_bound(offsets->begin(), offsets->end(), lookup_key);
|
|
|
|
// This code is easiest to understand with a concrete example.
|
|
// Here's a possible offsets array:
|
|
// {{offset = 3211, header_num = 0, file_num = 1, last, line_num = 16}, // 0
|
|
// {offset = 3224, header_num = 0, file_num = 1, last, line_num = 20}, // 1
|
|
// {offset = 3226, header_num = 0, file_num = 1, last, line_num = 22}, // 2
|
|
// {offset = 3231, header_num = 0, file_num = 1, last, line_num = 25}, // 3
|
|
// {offset = 3232, header_num = 0, file_num = 1, last, line_num = -1}, // 4
|
|
// {offset = 3232, header_num = 0, file_num = 1, last, line_num = 65}, // 5
|
|
// {offset = 3235, header_num = 0, file_num = 1, last, line_num = 66}, // 6
|
|
// {offset = 3236, header_num = 0, file_num = 1, last, line_num = -1}, // 7
|
|
// {offset = 5764, header_num = 0, file_num = 1, last, line_num = 48}, // 8
|
|
// {offset = 5764, header_num = 0, file_num = 1,!last, line_num = 47}, // 9
|
|
// {offset = 5765, header_num = 0, file_num = 1, last, line_num = 49}, // 10
|
|
// {offset = 5767, header_num = 0, file_num = 1, last, line_num = 50}, // 11
|
|
// {offset = 5768, header_num = 0, file_num = 1, last, line_num = 51}, // 12
|
|
// {offset = 5773, header_num = 0, file_num = 1, last, line_num = -1}, // 13
|
|
// {offset = 5787, header_num = 1, file_num = 1, last, line_num = 19}, // 14
|
|
// {offset = 5790, header_num = 1, file_num = 1, last, line_num = 20}, // 15
|
|
// {offset = 5793, header_num = 1, file_num = 1, last, line_num = 67}, // 16
|
|
// {offset = 5793, header_num = 1, file_num = 1, last, line_num = -1}, // 17
|
|
// {offset = 5793, header_num = 1, file_num = 1,!last, line_num = 66}, // 18
|
|
// {offset = 5795, header_num = 1, file_num = 1, last, line_num = 68}, // 19
|
|
// {offset = 5798, header_num = 1, file_num = 1, last, line_num = -1}, // 20
|
|
// The entries with line_num == -1 mark the end of a function: the
|
|
// associated offset is one past the last instruction in the
|
|
// function. This can correspond to the beginning of the next
|
|
// function (as is true for offset 3232); alternately, there can be
|
|
// a gap between the end of one function and the start of the next
|
|
// (as is true for some others, most obviously from 3236->5764).
|
|
//
|
|
// Case 1: lookup_key has offset == 10. lower_bound returns
|
|
// offsets[0]. Since it's not an exact match and we're
|
|
// at the beginning of offsets, we return end() (invalid).
|
|
// Case 2: lookup_key has offset 10000. lower_bound returns
|
|
// offset[21] (end()). We return end() (invalid).
|
|
// Case 3: lookup_key has offset == 3211. lower_bound matches
|
|
// offsets[0] exactly, and that's the entry we return.
|
|
// Case 4: lookup_key has offset == 3232. lower_bound returns
|
|
// offsets[4]. That's an exact match, but indicates
|
|
// end-of-function. We check if offsets[5] is also an
|
|
// exact match but not end-of-function. It is, so we
|
|
// return offsets[5].
|
|
// Case 5: lookup_key has offset == 3214. lower_bound returns
|
|
// offsets[1]. Since it's not an exact match, we back
|
|
// up to the offset that's < lookup_key, offsets[0].
|
|
// We note offsets[0] is a valid entry (not end-of-function),
|
|
// so that's the entry we return.
|
|
// Case 6: lookup_key has offset == 4000. lower_bound returns
|
|
// offsets[8]. Since it's not an exact match, we back
|
|
// up to offsets[7]. Since offsets[7] indicates
|
|
// end-of-function, we know lookup_key is between
|
|
// functions, so we return end() (not a valid offset).
|
|
// Case 7: lookup_key has offset == 5794. lower_bound returns
|
|
// offsets[19]. Since it's not an exact match, we back
|
|
// up to offsets[16]. Note we back up to the *first*
|
|
// entry with offset 5793, not just offsets[19-1].
|
|
// We note offsets[16] is a valid entry, so we return it.
|
|
// If offsets[16] had had line_num == -1, we would have
|
|
// checked offsets[17]. The reason for this is that
|
|
// 16 and 17 can be in an arbitrary order, since we sort
|
|
// only by offset and last_line_for_offset. (Note it
|
|
// doesn't help to use line_number as a tertiary sort key,
|
|
// since sometimes we want the -1 to be first and sometimes
|
|
// we want it to be last.)
|
|
|
|
// This deals with cases (1) and (2).
|
|
if ((it == offsets->begin() && offset < it->offset)
|
|
|| it == offsets->end())
|
|
return offsets->end();
|
|
|
|
// This deals with cases (3) and (4).
|
|
if (offset == it->offset)
|
|
{
|
|
while (it != offsets->end()
|
|
&& it->offset == offset
|
|
&& it->line_num == -1)
|
|
++it;
|
|
if (it == offsets->end() || it->offset != offset)
|
|
return offsets->end();
|
|
else
|
|
return it;
|
|
}
|
|
|
|
// This handles the first part of case (7) -- we back up to the
|
|
// *first* entry that has the offset that's behind us.
|
|
gold_assert(it != offsets->begin());
|
|
std::vector<Offset_to_lineno_entry>::const_iterator range_end = it;
|
|
--it;
|
|
const off_t range_value = it->offset;
|
|
while (it != offsets->begin() && (it-1)->offset == range_value)
|
|
--it;
|
|
|
|
// This handles cases (5), (6), and (7): if any entry in the
|
|
// equal_range [it, range_end) has a line_num != -1, it's a valid
|
|
// match. If not, we're not in a function. The line number we saw
|
|
// last for an offset will be sorted first, so it'll get returned if
|
|
// it's present.
|
|
for (; it != range_end; ++it)
|
|
if (it->line_num != -1)
|
|
return it;
|
|
return offsets->end();
|
|
}
|
|
|
|
// Returns the canonical filename:lineno for the address passed in.
|
|
// If other_lines is not NULL, appends the non-canonical lines
|
|
// assigned to the same address.
|
|
|
|
template<int size, bool big_endian>
|
|
std::string
|
|
Sized_dwarf_line_info<size, big_endian>::do_addr2line(
|
|
unsigned int shndx,
|
|
off_t offset,
|
|
std::vector<std::string>* other_lines)
|
|
{
|
|
if (this->data_valid_ == false)
|
|
return "";
|
|
|
|
const std::vector<Offset_to_lineno_entry>* offsets;
|
|
// If we do not have reloc information, then our input is a .so or
|
|
// some similar data structure where all the information is held in
|
|
// the offset. In that case, we ignore the input shndx.
|
|
if (this->input_is_relobj())
|
|
offsets = &this->line_number_map_[shndx];
|
|
else
|
|
offsets = &this->line_number_map_[-1U];
|
|
if (offsets->empty())
|
|
return "";
|
|
|
|
typename std::vector<Offset_to_lineno_entry>::const_iterator it
|
|
= offset_to_iterator(offsets, offset);
|
|
if (it == offsets->end())
|
|
return "";
|
|
|
|
std::string result = this->format_file_lineno(*it);
|
|
if (other_lines != NULL)
|
|
for (++it; it != offsets->end() && it->offset == offset; ++it)
|
|
{
|
|
if (it->line_num == -1)
|
|
continue; // The end of a previous function.
|
|
other_lines->push_back(this->format_file_lineno(*it));
|
|
}
|
|
return result;
|
|
}
|
|
|
|
// Convert the file_num + line_num into a string.
|
|
|
|
template<int size, bool big_endian>
|
|
std::string
|
|
Sized_dwarf_line_info<size, big_endian>::format_file_lineno(
|
|
const Offset_to_lineno_entry& loc) const
|
|
{
|
|
std::string ret;
|
|
|
|
gold_assert(loc.header_num < static_cast<int>(this->files_.size()));
|
|
gold_assert(loc.file_num
|
|
< static_cast<unsigned int>(this->files_[loc.header_num].size()));
|
|
const std::pair<int, std::string>& filename_pair
|
|
= this->files_[loc.header_num][loc.file_num];
|
|
const std::string& filename = filename_pair.second;
|
|
|
|
gold_assert(loc.header_num < static_cast<int>(this->directories_.size()));
|
|
gold_assert(filename_pair.first
|
|
< static_cast<int>(this->directories_[loc.header_num].size()));
|
|
const std::string& dirname
|
|
= this->directories_[loc.header_num][filename_pair.first];
|
|
|
|
if (!dirname.empty())
|
|
{
|
|
ret += dirname;
|
|
ret += "/";
|
|
}
|
|
ret += filename;
|
|
if (ret.empty())
|
|
ret = "(unknown)";
|
|
|
|
char buffer[64]; // enough to hold a line number
|
|
snprintf(buffer, sizeof(buffer), "%d", loc.line_num);
|
|
ret += ":";
|
|
ret += buffer;
|
|
|
|
return ret;
|
|
}
|
|
|
|
// Dwarf_line_info routines.
|
|
|
|
static unsigned int next_generation_count = 0;
|
|
|
|
struct Addr2line_cache_entry
|
|
{
|
|
Object* object;
|
|
unsigned int shndx;
|
|
Dwarf_line_info* dwarf_line_info;
|
|
unsigned int generation_count;
|
|
unsigned int access_count;
|
|
|
|
Addr2line_cache_entry(Object* o, unsigned int s, Dwarf_line_info* d)
|
|
: object(o), shndx(s), dwarf_line_info(d),
|
|
generation_count(next_generation_count), access_count(0)
|
|
{
|
|
if (next_generation_count < (1U << 31))
|
|
++next_generation_count;
|
|
}
|
|
};
|
|
// We expect this cache to be small, so don't bother with a hashtable
|
|
// or priority queue or anything: just use a simple vector.
|
|
static std::vector<Addr2line_cache_entry> addr2line_cache;
|
|
|
|
std::string
|
|
Dwarf_line_info::one_addr2line(Object* object,
|
|
unsigned int shndx, off_t offset,
|
|
size_t cache_size,
|
|
std::vector<std::string>* other_lines)
|
|
{
|
|
Dwarf_line_info* lineinfo = NULL;
|
|
std::vector<Addr2line_cache_entry>::iterator it;
|
|
|
|
// First, check the cache. If we hit, update the counts.
|
|
for (it = addr2line_cache.begin(); it != addr2line_cache.end(); ++it)
|
|
{
|
|
if (it->object == object && it->shndx == shndx)
|
|
{
|
|
lineinfo = it->dwarf_line_info;
|
|
it->generation_count = next_generation_count;
|
|
// We cap generation_count at 2^31 -1 to avoid overflow.
|
|
if (next_generation_count < (1U << 31))
|
|
++next_generation_count;
|
|
// We cap access_count at 31 so 2^access_count doesn't overflow
|
|
if (it->access_count < 31)
|
|
++it->access_count;
|
|
break;
|
|
}
|
|
}
|
|
|
|
// If we don't hit the cache, create a new object and insert into the
|
|
// cache.
|
|
if (lineinfo == NULL)
|
|
{
|
|
switch (parameters->size_and_endianness())
|
|
{
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
|
case Parameters::TARGET_32_LITTLE:
|
|
lineinfo = new Sized_dwarf_line_info<32, false>(object, shndx); break;
|
|
#endif
|
|
#ifdef HAVE_TARGET_32_BIG
|
|
case Parameters::TARGET_32_BIG:
|
|
lineinfo = new Sized_dwarf_line_info<32, true>(object, shndx); break;
|
|
#endif
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
|
case Parameters::TARGET_64_LITTLE:
|
|
lineinfo = new Sized_dwarf_line_info<64, false>(object, shndx); break;
|
|
#endif
|
|
#ifdef HAVE_TARGET_64_BIG
|
|
case Parameters::TARGET_64_BIG:
|
|
lineinfo = new Sized_dwarf_line_info<64, true>(object, shndx); break;
|
|
#endif
|
|
default:
|
|
gold_unreachable();
|
|
}
|
|
addr2line_cache.push_back(Addr2line_cache_entry(object, shndx, lineinfo));
|
|
}
|
|
|
|
// Now that we have our object, figure out the answer
|
|
std::string retval = lineinfo->addr2line(shndx, offset, other_lines);
|
|
|
|
// Finally, if our cache has grown too big, delete old objects. We
|
|
// assume the common (probably only) case is deleting only one object.
|
|
// We use a pretty simple scheme to evict: function of LRU and MFU.
|
|
while (addr2line_cache.size() > cache_size)
|
|
{
|
|
unsigned int lowest_score = ~0U;
|
|
std::vector<Addr2line_cache_entry>::iterator lowest
|
|
= addr2line_cache.end();
|
|
for (it = addr2line_cache.begin(); it != addr2line_cache.end(); ++it)
|
|
{
|
|
const unsigned int score = (it->generation_count
|
|
+ (1U << it->access_count));
|
|
if (score < lowest_score)
|
|
{
|
|
lowest_score = score;
|
|
lowest = it;
|
|
}
|
|
}
|
|
if (lowest != addr2line_cache.end())
|
|
{
|
|
delete lowest->dwarf_line_info;
|
|
addr2line_cache.erase(lowest);
|
|
}
|
|
}
|
|
|
|
return retval;
|
|
}
|
|
|
|
void
|
|
Dwarf_line_info::clear_addr2line_cache()
|
|
{
|
|
for (std::vector<Addr2line_cache_entry>::iterator it = addr2line_cache.begin();
|
|
it != addr2line_cache.end();
|
|
++it)
|
|
delete it->dwarf_line_info;
|
|
addr2line_cache.clear();
|
|
}
|
|
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
|
template
|
|
class Sized_dwarf_line_info<32, false>;
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_BIG
|
|
template
|
|
class Sized_dwarf_line_info<32, true>;
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
|
template
|
|
class Sized_dwarf_line_info<64, false>;
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_BIG
|
|
template
|
|
class Sized_dwarf_line_info<64, true>;
|
|
#endif
|
|
|
|
} // End namespace gold.
|