binutils-gdb/gold/gdb-index.h

265 lines
7.3 KiB
C++

// gdb-index.h -- generate .gdb_index section for fast debug lookup -*- C++ -*-
// Copyright (C) 2012-2018 Free Software Foundation, Inc.
// Written by Cary Coutant <ccoutant@google.com>.
// This file is part of gold.
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
// MA 02110-1301, USA.
#include <sys/types.h>
#include <vector>
#include "gold.h"
#include "output.h"
#include "mapfile.h"
#include "stringpool.h"
#ifndef GOLD_GDB_INDEX_H
#define GOLD_GDB_INDEX_H
namespace gold
{
class Output_section;
class Output_file;
class Mapfile;
template<int size, bool big_endian>
class Sized_relobj;
class Dwarf_range_list;
template <typename T>
class Gdb_hashtab;
class Gdb_index_info_reader;
class Dwarf_pubnames_table;
// This class manages the .gdb_index section, which is a fast
// lookup table for DWARF information used by the gdb debugger.
// The format of this section is described in gdb/doc/gdb.texinfo.
class Gdb_index : public Output_section_data
{
public:
Gdb_index(Output_section* gdb_index_section);
~Gdb_index();
// Scan a .debug_info or .debug_types input section.
void scan_debug_info(bool is_type_unit,
Relobj* object,
const unsigned char* symbols,
off_t symbols_size,
unsigned int shndx,
unsigned int reloc_shndx,
unsigned int reloc_type);
// Add a compilation unit.
int
add_comp_unit(off_t cu_offset, off_t cu_length)
{
this->comp_units_.push_back(Comp_unit(cu_offset, cu_length));
return this->comp_units_.size() - 1;
}
// Add a type unit.
int
add_type_unit(off_t tu_offset, off_t type_offset, uint64_t signature)
{
this->type_units_.push_back(Type_unit(tu_offset, type_offset, signature));
return this->type_units_.size() - 1;
}
// Add an address range.
void
add_address_range_list(Relobj* object, unsigned int cu_index,
Dwarf_range_list* ranges)
{
this->ranges_.push_back(Per_cu_range_list(object, cu_index, ranges));
}
// Add a symbol. FLAGS are the gdb_index version 7 flags to be stored in
// the high-byte of the cu_index field.
void
add_symbol(int cu_index, const char* sym_name, uint8_t flags);
// Return the offset into the pubnames table for the cu at the given
// offset.
off_t
find_pubname_offset(off_t cu_offset);
// Return the offset into the pubtypes table for the cu at the
// given offset.
off_t
find_pubtype_offset(off_t cu_offset);
// Return TRUE if we have already processed the pubnames and types
// set for OBJECT of the CUs and TUS associated with the statement
// list at OFFSET.
bool
pubnames_read(const Relobj* object, off_t offset);
// Record that we have already read the pubnames associated with
// OBJECT and OFFSET.
void
set_pubnames_read(const Relobj* object, off_t offset);
// Return a pointer to the given table.
Dwarf_pubnames_table*
pubnames_table()
{ return pubnames_table_; }
Dwarf_pubnames_table*
pubtypes_table()
{ return pubtypes_table_; }
// Print usage statistics.
static void
print_stats();
protected:
// This is called to update the section size prior to assigning
// the address and file offset.
void
update_data_size()
{ this->set_final_data_size(); }
// Set the final data size.
void
set_final_data_size();
// Write the data to the file.
void
do_write(Output_file*);
// Write to a map file.
void
do_print_to_mapfile(Mapfile* mapfile) const
{ mapfile->print_output_data(this, _("** gdb_index")); }
// Create a map from dies to pubnames.
Dwarf_pubnames_table*
map_pubtable_to_dies(unsigned int attr,
Gdb_index_info_reader* dwinfo,
Relobj* object,
const unsigned char* symbols,
off_t symbols_size);
// Wrapper for map_pubtable_to_dies
void
map_pubnames_and_types_to_dies(Gdb_index_info_reader* dwinfo,
Relobj* object,
const unsigned char* symbols,
off_t symbols_size);
private:
// An entry in the compilation unit list.
struct Comp_unit
{
Comp_unit(off_t off, off_t len)
: cu_offset(off), cu_length(len)
{ }
uint64_t cu_offset;
uint64_t cu_length;
};
// An entry in the type unit list.
struct Type_unit
{
Type_unit(off_t off, off_t toff, uint64_t sig)
: tu_offset(off), type_offset(toff), type_signature(sig)
{ }
uint64_t tu_offset;
uint64_t type_offset;
uint64_t type_signature;
};
// An entry in the address range list.
struct Per_cu_range_list
{
Per_cu_range_list(Relobj* obj, uint32_t index, Dwarf_range_list* r)
: object(obj), cu_index(index), ranges(r)
{ }
Relobj* object;
uint32_t cu_index;
Dwarf_range_list* ranges;
};
// A symbol table entry.
struct Gdb_symbol
{
Stringpool::Key name_key;
unsigned int hashval;
unsigned int cu_vector_index;
// Return the hash value.
unsigned int
hash()
{ return this->hashval; }
// Return true if this symbol is the same as SYMBOL.
bool
equal(Gdb_symbol* symbol)
{ return this->name_key == symbol->name_key; }
};
typedef std::vector<std::pair<int, uint8_t> > Cu_vector;
typedef Unordered_map<off_t, off_t> Pubname_offset_map;
Pubname_offset_map cu_pubname_map_;
Pubname_offset_map cu_pubtype_map_;
// Scan the given pubtable and build a map of the various dies it
// refers to, so we can process the entries when we encounter the
// die.
void
map_pubtable_to_dies(Dwarf_pubnames_table* table,
Pubname_offset_map* map);
// Tables to store the pubnames section of the current object.
Dwarf_pubnames_table* pubnames_table_;
Dwarf_pubnames_table* pubtypes_table_;
// The .gdb_index section.
Output_section* gdb_index_section_;
// The list of DWARF compilation units.
std::vector<Comp_unit> comp_units_;
// The list of DWARF type units.
std::vector<Type_unit> type_units_;
// The list of address ranges.
std::vector<Per_cu_range_list> ranges_;
// The symbol table.
Gdb_hashtab<Gdb_symbol>* gdb_symtab_;
// The CU vector portion of the constant pool.
std::vector<Cu_vector*> cu_vector_list_;
// An array to map from a CU vector index to an offset to the constant pool.
off_t* cu_vector_offsets_;
// The string portion of the constant pool.
Stringpool stringpool_;
// Offsets of the various pieces of the .gdb_index section.
off_t tu_offset_;
off_t addr_offset_;
off_t symtab_offset_;
off_t cu_pool_offset_;
off_t stringpool_offset_;
// Object, stmt list offset of the CUs and TUs associated with the
// last read pubnames and pubtypes sections.
const Relobj* pubnames_object_;
off_t stmt_list_offset_;
};
} // End namespace gold.
#endif // !defined(GOLD_GDB_INDEX_H)