// dwarf_reader.cc -- parse dwarf2/3 debug information
-// Copyright 2007 Free Software Foundation, Inc.
+// Copyright (C) 2007-2021 Free Software Foundation, Inc.
// Written by Ian Lance Taylor <iant@google.com>.
// This file is part of gold.
#include "gold.h"
+#include <algorithm>
+#include <utility>
+#include <vector>
+
#include "elfcpp_swap.h"
#include "dwarf.h"
#include "object.h"
-#include "parameters.h"
#include "reloc.h"
#include "dwarf_reader.h"
+#include "int_encoding.h"
+#include "compressed_output.h"
+
+namespace gold {
-namespace {
+// Class Sized_elf_reloc_mapper
-// Read an unsigned LEB128 number. Each byte contains 7 bits of
-// information, plus one bit saying whether the number continues or
-// not.
+// Initialize the relocation tracker for section RELOC_SHNDX.
-uint64_t
-read_unsigned_LEB_128(const unsigned char* buffer, size_t* len)
+template<int size, bool big_endian>
+bool
+Sized_elf_reloc_mapper<size, big_endian>::do_initialize(
+ unsigned int reloc_shndx, unsigned int reloc_type)
{
- uint64_t result = 0;
- size_t num_read = 0;
- unsigned int shift = 0;
- unsigned char byte;
+ this->reloc_type_ = reloc_type;
+ return this->track_relocs_.initialize(this->object_, reloc_shndx,
+ reloc_type);
+}
- do
+// Looks in the symtab to see what section a symbol is in.
+
+template<int size, bool big_endian>
+unsigned int
+Sized_elf_reloc_mapper<size, big_endian>::symbol_section(
+ unsigned int symndx, Address* value, bool* is_ordinary)
+{
+ const int symsize = elfcpp::Elf_sizes<size>::sym_size;
+ gold_assert(static_cast<off_t>((symndx + 1) * symsize) <= this->symtab_size_);
+ elfcpp::Sym<size, big_endian> elfsym(this->symtab_ + symndx * symsize);
+ *value = elfsym.get_st_value();
+ return this->object_->adjust_sym_shndx(symndx, elfsym.get_st_shndx(),
+ is_ordinary);
+}
+
+// Return the section index and offset within the section of
+// the target of the relocation for RELOC_OFFSET.
+
+template<int size, bool big_endian>
+unsigned int
+Sized_elf_reloc_mapper<size, big_endian>::do_get_reloc_target(
+ off_t reloc_offset, off_t* target_offset)
+{
+ this->track_relocs_.advance(reloc_offset);
+ if (reloc_offset != this->track_relocs_.next_offset())
+ return 0;
+ unsigned int symndx = this->track_relocs_.next_symndx();
+ typename elfcpp::Elf_types<size>::Elf_Addr value;
+ bool is_ordinary;
+ unsigned int target_shndx = this->symbol_section(symndx, &value,
+ &is_ordinary);
+ if (!is_ordinary)
+ return 0;
+ if (this->reloc_type_ == elfcpp::SHT_RELA)
+ value += this->track_relocs_.next_addend();
+ *target_offset = value;
+ return target_shndx;
+}
+
+static inline Elf_reloc_mapper*
+make_elf_reloc_mapper(Relobj* object, const unsigned char* symtab,
+ off_t symtab_size)
+{
+ if (object->elfsize() == 32)
{
- byte = *buffer++;
- num_read++;
- result |= (static_cast<uint64_t>(byte & 0x7f)) << shift;
- shift += 7;
+ if (object->is_big_endian())
+ {
+#ifdef HAVE_TARGET_32_BIG
+ return new Sized_elf_reloc_mapper<32, true>(object, symtab,
+ symtab_size);
+#else
+ gold_unreachable();
+#endif
+ }
+ else
+ {
+#ifdef HAVE_TARGET_32_LITTLE
+ return new Sized_elf_reloc_mapper<32, false>(object, symtab,
+ symtab_size);
+#else
+ gold_unreachable();
+#endif
+ }
+ }
+ else if (object->elfsize() == 64)
+ {
+ if (object->is_big_endian())
+ {
+#ifdef HAVE_TARGET_64_BIG
+ return new Sized_elf_reloc_mapper<64, true>(object, symtab,
+ symtab_size);
+#else
+ gold_unreachable();
+#endif
+ }
+ else
+ {
+#ifdef HAVE_TARGET_64_LITTLE
+ return new Sized_elf_reloc_mapper<64, false>(object, symtab,
+ symtab_size);
+#else
+ gold_unreachable();
+#endif
+ }
}
- while (byte & 0x80);
+ else
+ gold_unreachable();
+}
- *len = num_read;
+// class Dwarf_abbrev_table
- return result;
+void
+Dwarf_abbrev_table::clear_abbrev_codes()
+{
+ for (unsigned int code = 0; code < this->low_abbrev_code_max_; ++code)
+ {
+ if (this->low_abbrev_codes_[code] != NULL)
+ {
+ delete this->low_abbrev_codes_[code];
+ this->low_abbrev_codes_[code] = NULL;
+ }
+ }
+ for (Abbrev_code_table::iterator it = this->high_abbrev_codes_.begin();
+ it != this->high_abbrev_codes_.end();
+ ++it)
+ {
+ if (it->second != NULL)
+ delete it->second;
+ }
+ this->high_abbrev_codes_.clear();
+}
+
+// Read the abbrev table from an object file.
+
+bool
+Dwarf_abbrev_table::do_read_abbrevs(
+ Relobj* object,
+ unsigned int abbrev_shndx,
+ off_t abbrev_offset)
+{
+ this->clear_abbrev_codes();
+
+ // If we don't have relocations, abbrev_shndx will be 0, and
+ // we'll have to hunt for the .debug_abbrev section.
+ if (abbrev_shndx == 0 && this->abbrev_shndx_ > 0)
+ abbrev_shndx = this->abbrev_shndx_;
+ else if (abbrev_shndx == 0)
+ {
+ for (unsigned int i = 1; i < object->shnum(); ++i)
+ {
+ std::string name = object->section_name(i);
+ if (name == ".debug_abbrev" || name == ".zdebug_abbrev")
+ {
+ abbrev_shndx = i;
+ // 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.
+ abbrev_offset -= object->output_section_offset(i);
+ break;
+ }
+ }
+ if (abbrev_shndx == 0)
+ return false;
+ }
+
+ // Get the section contents and decompress if necessary.
+ if (abbrev_shndx != this->abbrev_shndx_)
+ {
+ if (this->owns_buffer_ && this->buffer_ != NULL)
+ {
+ delete[] this->buffer_;
+ this->owns_buffer_ = false;
+ }
+
+ section_size_type buffer_size;
+ this->buffer_ =
+ object->decompressed_section_contents(abbrev_shndx,
+ &buffer_size,
+ &this->owns_buffer_);
+ this->buffer_end_ = this->buffer_ + buffer_size;
+ this->abbrev_shndx_ = abbrev_shndx;
+ }
+
+ this->buffer_pos_ = this->buffer_ + abbrev_offset;
+ return true;
+}
+
+// Lookup the abbrev code entry for CODE. This function is called
+// only when the abbrev code is not in the direct lookup table.
+// It may be in the hash table, it may not have been read yet,
+// or it may not exist in the abbrev table.
+
+const Dwarf_abbrev_table::Abbrev_code*
+Dwarf_abbrev_table::do_get_abbrev(unsigned int code)
+{
+ // See if the abbrev code is already in the hash table.
+ Abbrev_code_table::const_iterator it = this->high_abbrev_codes_.find(code);
+ if (it != this->high_abbrev_codes_.end())
+ return it->second;
+
+ // Read and store abbrev code definitions until we find the
+ // one we're looking for.
+ for (;;)
+ {
+ // Read the abbrev code. A zero here indicates the end of the
+ // abbrev table.
+ size_t len;
+ if (this->buffer_pos_ >= this->buffer_end_)
+ return NULL;
+ uint64_t nextcode = read_unsigned_LEB_128(this->buffer_pos_, &len);
+ if (nextcode == 0)
+ {
+ this->buffer_pos_ = this->buffer_end_;
+ return NULL;
+ }
+ this->buffer_pos_ += len;
+
+ // Read the tag.
+ if (this->buffer_pos_ >= this->buffer_end_)
+ return NULL;
+ uint64_t tag = read_unsigned_LEB_128(this->buffer_pos_, &len);
+ this->buffer_pos_ += len;
+
+ // Read the has_children flag.
+ if (this->buffer_pos_ >= this->buffer_end_)
+ return NULL;
+ bool has_children = *this->buffer_pos_ == elfcpp::DW_CHILDREN_yes;
+ this->buffer_pos_ += 1;
+
+ // Read the list of (attribute, form) pairs.
+ Abbrev_code* entry = new Abbrev_code(tag, has_children);
+ for (;;)
+ {
+ // Read the attribute.
+ if (this->buffer_pos_ >= this->buffer_end_)
+ return NULL;
+ uint64_t attr = read_unsigned_LEB_128(this->buffer_pos_, &len);
+ this->buffer_pos_ += len;
+
+ // Read the form.
+ if (this->buffer_pos_ >= this->buffer_end_)
+ return NULL;
+ uint64_t form = read_unsigned_LEB_128(this->buffer_pos_, &len);
+ this->buffer_pos_ += len;
+
+ // A (0,0) pair terminates the list.
+ if (attr == 0 && form == 0)
+ break;
+
+ if (attr == elfcpp::DW_AT_sibling)
+ entry->has_sibling_attribute = true;
+
+ entry->add_attribute(attr, form);
+ }
+
+ this->store_abbrev(nextcode, entry);
+ if (nextcode == code)
+ return entry;
+ }
+
+ return NULL;
+}
+
+// class Dwarf_ranges_table
+
+// Read the ranges table from an object file.
+
+bool
+Dwarf_ranges_table::read_ranges_table(
+ Relobj* object,
+ const unsigned char* symtab,
+ off_t symtab_size,
+ unsigned int ranges_shndx)
+{
+ // If we've already read this abbrev table, return immediately.
+ if (this->ranges_shndx_ > 0
+ && this->ranges_shndx_ == ranges_shndx)
+ return true;
+
+ // If we don't have relocations, ranges_shndx will be 0, and
+ // we'll have to hunt for the .debug_ranges section.
+ if (ranges_shndx == 0 && this->ranges_shndx_ > 0)
+ ranges_shndx = this->ranges_shndx_;
+ else if (ranges_shndx == 0)
+ {
+ for (unsigned int i = 1; i < object->shnum(); ++i)
+ {
+ std::string name = object->section_name(i);
+ if (name == ".debug_ranges" || name == ".zdebug_ranges")
+ {
+ ranges_shndx = i;
+ this->output_section_offset_ = object->output_section_offset(i);
+ break;
+ }
+ }
+ if (ranges_shndx == 0)
+ return false;
+ }
+
+ // Get the section contents and decompress if necessary.
+ if (ranges_shndx != this->ranges_shndx_)
+ {
+ if (this->owns_ranges_buffer_ && this->ranges_buffer_ != NULL)
+ {
+ delete[] this->ranges_buffer_;
+ this->owns_ranges_buffer_ = false;
+ }
+
+ section_size_type buffer_size;
+ this->ranges_buffer_ =
+ object->decompressed_section_contents(ranges_shndx,
+ &buffer_size,
+ &this->owns_ranges_buffer_);
+ this->ranges_buffer_end_ = this->ranges_buffer_ + buffer_size;
+ this->ranges_shndx_ = ranges_shndx;
+ }
+
+ if (this->ranges_reloc_mapper_ != NULL)
+ {
+ delete this->ranges_reloc_mapper_;
+ this->ranges_reloc_mapper_ = NULL;
+ }
+
+ // For incremental objects, we have no relocations.
+ if (object->is_incremental())
+ return true;
+
+ // Find the relocation section for ".debug_ranges".
+ 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) == ranges_shndx)
+ {
+ reloc_shndx = i;
+ break;
+ }
+ }
+
+ this->ranges_reloc_mapper_ = make_elf_reloc_mapper(object, symtab,
+ symtab_size);
+ this->ranges_reloc_mapper_->initialize(reloc_shndx, reloc_type);
+ this->reloc_type_ = reloc_type;
+
+ return true;
+}
+
+// Read a range list from section RANGES_SHNDX at offset RANGES_OFFSET.
+
+Dwarf_range_list*
+Dwarf_ranges_table::read_range_list(
+ Relobj* object,
+ const unsigned char* symtab,
+ off_t symtab_size,
+ unsigned int addr_size,
+ unsigned int ranges_shndx,
+ off_t offset)
+{
+ Dwarf_range_list* ranges;
+
+ if (!this->read_ranges_table(object, symtab, symtab_size, ranges_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.
+ offset -= this->output_section_offset_;
+
+ // Read the range list at OFFSET.
+ ranges = new Dwarf_range_list();
+ off_t base = 0;
+ for (;
+ this->ranges_buffer_ + offset < this->ranges_buffer_end_;
+ offset += 2 * addr_size)
+ {
+ off_t start;
+ off_t end;
+
+ // Read the raw contents of the section.
+ if (addr_size == 4)
+ {
+ start = this->dwinfo_->read_from_pointer<32>(this->ranges_buffer_
+ + offset);
+ end = this->dwinfo_->read_from_pointer<32>(this->ranges_buffer_
+ + offset + 4);
+ }
+ else
+ {
+ start = this->dwinfo_->read_from_pointer<64>(this->ranges_buffer_
+ + offset);
+ end = this->dwinfo_->read_from_pointer<64>(this->ranges_buffer_
+ + offset + 8);
+ }
+
+ // Check for relocations and adjust the values.
+ unsigned int shndx1 = 0;
+ unsigned int shndx2 = 0;
+ if (this->ranges_reloc_mapper_ != NULL)
+ {
+ shndx1 = this->lookup_reloc(offset, &start);
+ shndx2 = this->lookup_reloc(offset + addr_size, &end);
+ }
+
+ // End of list is marked by a pair of zeroes.
+ if (shndx1 == 0 && start == 0 && end == 0)
+ break;
+
+ // A "base address selection entry" is identified by
+ // 0xffffffff for the first value of the pair. The second
+ // value is used as a base for subsequent range list entries.
+ if (shndx1 == 0 && start == -1)
+ base = end;
+ else if (shndx1 == shndx2)
+ {
+ if (shndx1 == 0 || object->is_section_included(shndx1))
+ ranges->add(shndx1, base + start, base + end);
+ }
+ else
+ gold_warning(_("%s: DWARF info may be corrupt; offsets in a "
+ "range list entry are in different sections"),
+ object->name().c_str());
+ }
+
+ return ranges;
+}
+
+// Look for a relocation at offset OFF in the range table,
+// and return the section index and offset of the target.
+
+unsigned int
+Dwarf_ranges_table::lookup_reloc(off_t off, off_t* target_off)
+{
+ off_t value;
+ unsigned int shndx =
+ this->ranges_reloc_mapper_->get_reloc_target(off, &value);
+ if (shndx == 0)
+ return 0;
+ if (this->reloc_type_ == elfcpp::SHT_REL)
+ *target_off += value;
+ else
+ *target_off = value;
+ return shndx;
+}
+
+// class Dwarf_pubnames_table
+
+// Read the pubnames section from the object file.
+
+bool
+Dwarf_pubnames_table::read_section(Relobj* object, const unsigned char* symtab,
+ off_t symtab_size)
+{
+ section_size_type buffer_size;
+ unsigned int shndx = 0;
+ const char* name = this->is_pubtypes_ ? "pubtypes" : "pubnames";
+ const char* gnu_name = (this->is_pubtypes_
+ ? "gnu_pubtypes"
+ : "gnu_pubnames");
+
+ for (unsigned int i = 1; i < object->shnum(); ++i)
+ {
+ std::string section_name = object->section_name(i);
+ const char* section_name_suffix = section_name.c_str();
+ if (is_prefix_of(".debug_", section_name_suffix))
+ section_name_suffix += 7;
+ else if (is_prefix_of(".zdebug_", section_name_suffix))
+ section_name_suffix += 8;
+ else
+ continue;
+ if (strcmp(section_name_suffix, name) == 0)
+ {
+ shndx = i;
+ break;
+ }
+ else if (strcmp(section_name_suffix, gnu_name) == 0)
+ {
+ shndx = 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);
+
+ 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;
+
+ // If unit_length is too big, maybe we should reject the whole table,
+ // but in cases we know about, it seems OK to assume that the table
+ // is valid through the actual end of the section.
+ if (this->end_of_table_ > this->buffer_end_)
+ this->end_of_table_ = this->buffer_end_;
+
+ // 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:
+ {
+ 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_ref_addr:
+ {
+ off_t sec_off;
+ if (this->dwinfo_->ref_addr_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:
+ pattr += this->dwinfo_->address_size();
+ break;
+ case elfcpp::DW_FORM_ref_addr:
+ pattr += this->dwinfo_->ref_addr_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);
}
-// Read a signed LEB128 number. These are like regular LEB128
-// numbers, except the last byte may have a sign bit set.
+// 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
-read_signed_LEB_128(const unsigned char* buffer, size_t* len)
+Dwarf_die::int_attribute(unsigned int attr)
{
- int64_t result = 0;
- int shift = 0;
- size_t num_read = 0;
- unsigned char byte;
+ 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;
+ }
+}
- do
+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)
{
- byte = *buffer++;
- num_read++;
- result |= (static_cast<uint64_t>(byte & 0x7f) << shift);
- shift += 7;
+ 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;
}
- while (byte & 0x80);
+}
- if ((shift < 8 * static_cast<int>(sizeof(result))) && (byte & 0x40))
- result |= -((static_cast<int64_t>(1)) << shift);
- *len = num_read;
- return result;
+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;
+ }
}
-} // End anonymous namespace.
+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;
+}
-namespace gold {
+// 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;
+}
-// This is the format of a DWARF2/3 line state machine that we process
-// opcodes using. There is no need for anything outside the lineinfo
-// processor to know how this works.
+// 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
{
}
template<int size, bool big_endian>
-Sized_dwarf_line_info<size, big_endian>::Sized_dwarf_line_info(Object* object,
- off_t read_shndx)
- : data_valid_(false), buffer_(NULL), symtab_buffer_(NULL),
- directories_(), files_(), current_header_index_(-1)
+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 = 0; debug_shndx < object->shnum(); ++debug_shndx)
- // FIXME: do this more efficiently: section_name() isn't super-fast
- if (object->section_name(debug_shndx) == ".debug_line")
- {
- section_size_type buffer_size;
- this->buffer_ = object->section_contents(debug_shndx, &buffer_size,
- false);
- this->buffer_end_ = this->buffer_ + buffer_size;
- break;
- }
+
+ 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).
- bool got_relocs = false;
- for (unsigned int reloc_shndx = 0;
- reloc_shndx < object->shnum();
- ++reloc_shndx)
+ unsigned int reloc_shndx = 0;
+ for (unsigned int i = 0; i < object->shnum(); ++i)
{
- unsigned int reloc_sh_type = object->section_type(reloc_shndx);
+ 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(reloc_shndx) == debug_shndx)
+ && object->section_info(i) == debug_shndx)
{
- got_relocs = this->track_relocs_.initialize(object, reloc_shndx,
- reloc_sh_type);
+ reloc_shndx = i;
+ this->track_relocs_type_ = reloc_sh_type;
break;
}
}
// Finally, we need the symtab section to interpret the relocs.
- if (got_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);
+ 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;
Sized_dwarf_line_info<size, big_endian>::read_header_prolog(
const unsigned char* lineptr)
{
- uint32_t initial_length = elfcpp::Swap<32, big_endian>::readval(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
if (initial_length == 0xffffffff)
{
header_.offset_size = 8;
- initial_length = elfcpp::Swap<64, big_endian>::readval(lineptr);
+ initial_length = elfcpp::Swap_unaligned<64, big_endian>::readval(lineptr);
lineptr += 8;
}
else
gold_assert(lineptr + header_.total_length <= buffer_end_);
- header_.version = elfcpp::Swap<16, big_endian>::readval(lineptr);
+ header_.version = elfcpp::Swap_unaligned<16, big_endian>::readval(lineptr);
lineptr += 2;
if (header_.offset_size == 4)
- header_.prologue_length = elfcpp::Swap<32, big_endian>::readval(lineptr);
+ header_.prologue_length = elfcpp::Swap_unaligned<32, big_endian>::readval(lineptr);
else
- header_.prologue_length = elfcpp::Swap<64, big_endian>::readval(lineptr);
+ header_.prologue_length = elfcpp::Swap_unaligned<64, big_endian>::readval(lineptr);
lineptr += header_.offset_size;
header_.min_insn_length = *lineptr;
lineptr += 1;
+ if (header_.version < 4)
+ header_.max_ops_per_insn = 1;
+ else
+ {
+ // DWARF 4 added the maximum_operations_per_instruction field.
+ header_.max_ops_per_insn = *lineptr;
+ lineptr += 1;
+ // TODO: Add support for values other than 1.
+ gold_assert(header_.max_ops_per_insn == 1);
+ }
+
header_.default_is_stmt = *lineptr;
lineptr += 1;
header_.opcode_base = *lineptr;
lineptr += 1;
- header_.std_opcode_lengths.reserve(header_.opcode_base + 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++)
{
// Process a single opcode in the .debug.line structure.
-// Templating on size and big_endian would yield more efficient (and
-// simpler) code, but would bloat the binary. Speed isn't important
-// here.
-
template<int size, bool big_endian>
bool
Sized_dwarf_line_info<size, big_endian>::process_one_opcode(
case elfcpp::DW_LNS_fixed_advance_pc:
{
int advance_address;
- advance_address = elfcpp::Swap<16, big_endian>::readval(start);
+ advance_address = elfcpp::Swap_unaligned<16, big_endian>::readval(start);
oplen += 2;
lsm->address += advance_address;
}
case elfcpp::DW_LNE_set_address:
{
- lsm->address = elfcpp::Swap<size, big_endian>::readval(start);
+ lsm->address =
+ elfcpp::Swap_unaligned<size, big_endian>::readval(start);
typename Reloc_map::const_iterator it
- = reloc_map_.find(start - this->buffer_);
+ = this->reloc_map_.find(start - this->buffer_);
if (it != reloc_map_.end())
{
- // value + addend.
- lsm->address += it->second.second;
+ // 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
start += templen;
uint64_t dirindex = read_unsigned_LEB_128(start, &templen);
- oplen += templen;
if (dirindex >= this->directories_.back().size())
dirindex = 0;
int dirindexi = static_cast<int>(dirindex);
- read_unsigned_LEB_128(start, &templen); // mod_time
- oplen += templen;
-
- read_unsigned_LEB_128(start, &templen); // filelength
- oplen += templen;
+ // 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));
template<int size, bool big_endian>
unsigned const char*
Sized_dwarf_line_info<size, big_endian>::read_lines(unsigned const char* lineptr,
- off_t shndx)
+ unsigned int shndx)
{
struct LineStateMachine lsm;
&& (shndx == -1U || lsm.shndx == -1U || shndx == lsm.shndx))
{
Offset_to_lineno_entry entry
- = { lsm.address, this->current_header_index_,
- lsm.file_num, lsm.line_num };
- line_number_map_[lsm.shndx].push_back(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;
}
-// Looks in the symtab to see what section a symbol is in.
-
-template<int size, bool big_endian>
-unsigned int
-Sized_dwarf_line_info<size, big_endian>::symbol_section(
- unsigned int sym,
- typename elfcpp::Elf_types<size>::Elf_Addr* value)
-{
- const int symsize = elfcpp::Elf_sizes<size>::sym_size;
- gold_assert(sym * symsize < this->symtab_buffer_size_);
- elfcpp::Sym<size, big_endian> elfsym(this->symtab_buffer_ + sym * symsize);
- *value = elfsym.get_st_value();
- return elfsym.get_st_shndx();
-}
-
// Read the relocations into a Reloc_map.
template<int size, bool big_endian>
if (this->symtab_buffer_ == NULL)
return;
- typename elfcpp::Elf_types<size>::Elf_Addr value;
+ off_t value;
off_t reloc_offset;
- while ((reloc_offset = this->track_relocs_.next_offset()) != -1)
+ while ((reloc_offset = this->reloc_mapper_->next_offset()) != -1)
{
- const unsigned int sym = this->track_relocs_.next_symndx();
- const unsigned int shndx = this->symbol_section(sym, &value);
- this->reloc_map_[reloc_offset] = std::make_pair(shndx, value);
- this->track_relocs_.advance(reloc_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);
}
}
template<int size, bool big_endian>
void
-Sized_dwarf_line_info<size, big_endian>::read_line_mappings(off_t shndx)
+Sized_dwarf_line_info<size, big_endian>::read_line_mappings(unsigned int shndx)
{
gold_assert(this->data_valid_ == true);
- read_relocs();
+ this->read_relocs();
while (this->buffer_ < this->buffer_end_)
{
const unsigned char* lineptr = this->buffer_;
offset_to_iterator(const std::vector<Offset_to_lineno_entry>* offsets,
off_t offset)
{
- const Offset_to_lineno_entry lookup_key = { offset, 0, 0, 0 };
+ 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().
// This code is easiest to understand with a concrete example.
// Here's a possible offsets array:
- // {{offset = 3211, header_num = 0, file_num = 1, line_num = 16}, // 0
- // {offset = 3224, header_num = 0, file_num = 1, line_num = 20}, // 1
- // {offset = 3226, header_num = 0, file_num = 1, line_num = 22}, // 2
- // {offset = 3231, header_num = 0, file_num = 1, line_num = 25}, // 3
- // {offset = 3232, header_num = 0, file_num = 1, line_num = -1}, // 4
- // {offset = 3232, header_num = 0, file_num = 1, line_num = 65}, // 5
- // {offset = 3235, header_num = 0, file_num = 1, line_num = 66}, // 6
- // {offset = 3236, header_num = 0, file_num = 1, line_num = -1}, // 7
- // {offset = 5764, header_num = 0, file_num = 1, line_num = 47}, // 8
- // {offset = 5765, header_num = 0, file_num = 1, line_num = 48}, // 9
- // {offset = 5767, header_num = 0, file_num = 1, line_num = 49}, // 10
- // {offset = 5768, header_num = 0, file_num = 1, line_num = 50}, // 11
- // {offset = 5773, header_num = 0, file_num = 1, line_num = -1}, // 12
- // {offset = 5787, header_num = 1, file_num = 1, line_num = 19}, // 13
- // {offset = 5790, header_num = 1, file_num = 1, line_num = 20}, // 14
- // {offset = 5793, header_num = 1, file_num = 1, line_num = 67}, // 15
- // {offset = 5793, header_num = 1, file_num = 1, line_num = -1}, // 16
- // {offset = 5795, header_num = 1, file_num = 1, line_num = 68}, // 17
- // {offset = 5798, header_num = 1, file_num = 1, line_num = -1}, // 18
+ // {{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
// 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[19] (end()). We return end() (invalid).
+ // 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
// 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[17]. Since it's not an exact match, we back
- // up to offsets[15]. Note we back up to the *first*
- // entry with offset 5793, not just offsets[17-1].
- // We note offsets[15] is a valid entry, so we return it.
- // If offsets[15] had had line_num == -1, we would have
- // checked offsets[16]. The reason for this is that
- // 15 and 16 can be in an arbitrary order, since we sort
- // only by offset. (Note it doesn't help to use line_number
- // as a secondary sort key, since sometimes we want the -1
- // to be first and sometimes we want it to be last.)
+ // 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)
// 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.
+ // 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();
}
-// Return a string for a file name and line number.
+// 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)
+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 "";
if (it == offsets->end())
return "";
- // Convert the file_num + line_num into a string.
+ std::string result = this->format_file_lineno(*it);
+ gold_debug(DEBUG_LOCATION, "do_addr2line: canonical result: %s",
+ result.c_str());
+ if (other_lines != NULL)
+ {
+ unsigned int last_file_num = it->file_num;
+ int last_line_num = it->line_num;
+ // Return up to 4 more locations from the beginning of the function
+ // for fuzzy matching.
+ for (++it; it != offsets->end(); ++it)
+ {
+ if (it->offset == offset && it->line_num == -1)
+ continue; // The end of a previous function.
+ if (it->line_num == -1)
+ break; // The end of the current function.
+ if (it->file_num != last_file_num || it->line_num != last_line_num)
+ {
+ other_lines->push_back(this->format_file_lineno(*it));
+ gold_debug(DEBUG_LOCATION, "do_addr2line: other: %s",
+ other_lines->back().c_str());
+ last_file_num = it->file_num;
+ last_line_num = it->line_num;
+ }
+ if (it->offset > offset && other_lines->size() >= 4)
+ break;
+ }
+ }
+
+ 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(it->header_num < static_cast<int>(this->files_.size()));
- gold_assert(it->file_num
- < static_cast<int>(this->files_[it->header_num].size()));
+ 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_[it->header_num][it->file_num];
+ = this->files_[loc.header_num][loc.file_num];
const std::string& filename = filename_pair.second;
- gold_assert(it->header_num < static_cast<int>(this->directories_.size()));
+ gold_assert(loc.header_num < static_cast<int>(this->directories_.size()));
gold_assert(filename_pair.first
- < static_cast<int>(this->directories_[it->header_num].size()));
+ < static_cast<int>(this->directories_[loc.header_num].size()));
const std::string& dirname
- = this->directories_[it->header_num][filename_pair.first];
+ = this->directories_[loc.header_num][filename_pair.first];
if (!dirname.empty())
{
ret = "(unknown)";
char buffer[64]; // enough to hold a line number
- snprintf(buffer, sizeof(buffer), "%d", it->line_num);
+ snprintf(buffer, sizeof(buffer), "%d", loc.line_num);
ret += ":";
ret += buffer;
// 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)
+ unsigned int shndx, off_t offset,
+ size_t cache_size,
+ std::vector<std::string>* other_lines)
{
- switch (parameters->size_and_endianness())
+ 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:
- return Sized_dwarf_line_info<32, false>(object, shndx).addr2line(shndx,
- offset);
+ 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:
- return Sized_dwarf_line_info<32, true>(object, shndx).addr2line(shndx,
- offset);
+ 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:
- return Sized_dwarf_line_info<64, false>(object, shndx).addr2line(shndx,
- offset);
+ 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:
- return Sized_dwarf_line_info<64, true>(object, shndx).addr2line(shndx,
- offset);
+ case Parameters::TARGET_64_BIG:
+ lineinfo = new Sized_dwarf_line_info<64, true>(object, shndx); break;
#endif
- default:
- gold_unreachable();
+ 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
projects / thirdparty / binutils-gdb.git / blobdiff