From ec673e648cf7b2fa6a03342b0bca3ed3855f002f Mon Sep 17 00:00:00 2001 From: Cary Coutant Date: Tue, 28 Jan 2014 15:35:47 -0800 Subject: Add .gdb_index version 7 support. This patch adds support for .gdb_index version 7, which adds several flag bits to the symbol index. It also fixes a problem where it did not handle compressed debug sections correctly. Tested with a google/gcc-4_8 branch compiler, which supports the -ggnu-pubnames option to generate .debug_gnu_pubnames/pubtypes tables. (We will submit that patch to GCC when stage 1 reopens.) 2014-01-28 Cary Coutant * gold/dwarf_reader.cc: include (for make_pair). (Dwarf_abbrev_table::do_read_abbrevs): Check for compressed debug sections. (Dwarf_ranges_table::read_ranges_table): Likewise. (Dwarf_pubnames_table::read_section): Check for GNU-style sections, and for compressed debug sections. (Dwarf_pubnames_table::read_header): Compute end address of table. (Dwarf_pubnames_table::next_name): Return flag_byte. Check for end of list by offset, not by offset == 0. (Dwarf_info_reader::do_read_string_table): Check for compressed debug sections. * gold/dwarf_reader.h (Dwarf_pubnames_table::Dwarf_pubnames_table): Initialize new data members. (Dwarf_pubnames_table::next_name): return flag_byte. (Dwarf_pubnames_table::end_of_table_): New data member. (Dwarf_pubnames_table::is_gnu_style_): New data member. * gold/gdb-index.cc (gdb_index_version): Update to version 7. (Gdb_index_info_reader::read_pubtable): Read flag_byte. (Gdb_index_info_reader::read_pubnames_and_pubtypes): Don't read skeleton type unit DIEs. (Gdb_index::add_symbol): Add flag_byte; adjust all callers. (Gdb_index::do_write): Write flag_byte. * gold/gdb-index.h (Gdb_index::add_symbol): Add flags parameter. (Gdb_index::Cu_vector): Store flags along with cu indexes. * gold/testsuite/gdb_index_test_3.sh: Allow versions 4-7. * gold/testsuite/gdb_index_test_comm.sh: Likewise. --- gold/gdb-index.cc | 32 +++++++++++++++++++++++--------- 1 file changed, 23 insertions(+), 9 deletions(-) (limited to 'gold/gdb-index.cc') diff --git a/gold/gdb-index.cc b/gold/gdb-index.cc index d42fbbd..1504abe 100644 --- a/gold/gdb-index.cc +++ b/gold/gdb-index.cc @@ -32,7 +32,7 @@ namespace gold { -const int gdb_index_version = 5; +const int gdb_index_version = 7; // Sizes of various records in the .gdb_index section. const int gdb_index_offset_size = 4; @@ -436,7 +436,8 @@ Gdb_index_info_reader::visit_die(Dwarf_die* die, Dwarf_die* context) // If the DIE is not a declaration, add it to the index. std::string full_name = this->get_qualified_name(die, context); if (!full_name.empty()) - this->gdb_index_->add_symbol(this->cu_index_, full_name.c_str()); + this->gdb_index_->add_symbol(this->cu_index_, + full_name.c_str(), 0); } break; case elfcpp::DW_TAG_typedef: @@ -476,7 +477,7 @@ Gdb_index_info_reader::visit_die(Dwarf_die* die, Dwarf_die* context) full_name = this->get_qualified_name(die, context); if (!full_name.empty()) this->gdb_index_->add_symbol(this->cu_index_, - full_name.c_str()); + full_name.c_str(), 0); } // We're interested in the children only for namespaces and @@ -870,11 +871,12 @@ Gdb_index_info_reader::read_pubtable(Dwarf_pubnames_table* table, off_t offset) return false; while (true) { - const char* name = table->next_name(); + uint8_t flag_byte; + const char* name = table->next_name(&flag_byte); if (name == NULL) break; - this->gdb_index_->add_symbol(this->cu_index_, name); + this->gdb_index_->add_symbol(this->cu_index_, name, flag_byte); } return true; } @@ -885,6 +887,14 @@ Gdb_index_info_reader::read_pubtable(Dwarf_pubnames_table* table, off_t offset) bool Gdb_index_info_reader::read_pubnames_and_pubtypes(Dwarf_die* die) { + // If this is a skeleton debug-type die (generated via + // -gsplit-dwarf), then the associated pubnames should have been + // read along with the corresponding CU. In any case, there isn't + // enough info inside to build a gdb index entry. + if (die->tag() == elfcpp::DW_TAG_type_unit + && die->string_attribute(elfcpp::DW_AT_GNU_dwo_name)) + return true; + // We use stmt_list_off as a unique identifier for the // compilation unit and its associated type units. unsigned int shndx; @@ -1112,7 +1122,7 @@ Gdb_index::scan_debug_info(bool is_type_unit, // Add a symbol. void -Gdb_index::add_symbol(int cu_index, const char* sym_name) +Gdb_index::add_symbol(int cu_index, const char* sym_name, uint8_t flags) { unsigned int hash = mapped_index_string_hash( reinterpret_cast(sym_name)); @@ -1139,8 +1149,10 @@ Gdb_index::add_symbol(int cu_index, const char* sym_name) // if it's not already on the list. We only need to // check the last added entry. Cu_vector* cu_vec = this->cu_vector_list_[found->cu_vector_index]; - if (cu_vec->size() == 0 || cu_vec->back() != cu_index) - cu_vec->push_back(cu_index); + if (cu_vec->size() == 0 + || cu_vec->back().first != cu_index + || cu_vec->back().second != flags) + cu_vec->push_back(std::make_pair(cu_index, flags)); } // Return TRUE if we have already processed the pubnames associated @@ -1317,9 +1329,11 @@ Gdb_index::do_write(Output_file* of) pov += 4; for (unsigned int j = 0; j < cu_vec->size(); ++j) { - int cu_index = (*cu_vec)[j]; + int cu_index = (*cu_vec)[j].first; + uint8_t flags = (*cu_vec)[j].second; if (cu_index < 0) cu_index = comp_units_count + (-1 - cu_index); + cu_index |= flags << 24; elfcpp::Swap<32, false>::writeval(pov, cu_index); pov += 4; } -- cgit v1.1