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  <ccoutant@google.com>

	* gold/dwarf_reader.cc: include <utility> (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.

1 files changed, 4 insertions, 3 deletions

diff --git a/gold/gdb-index.h b/gold/gdb-index.h
index 5d9fe476452..babde4a355d 100644
--- a/gold/gdb-index.h
+++ b/gold/gdb-index.h
@@ -89,9 +89,10 @@ class Gdb_index : public Output_section_data
     this->ranges_.push_back(Per_cu_range_list(object, cu_index, ranges));
   }
 
-  // Add a symbol.
+  // 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);
+  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.
@@ -213,7 +214,7 @@ class Gdb_index : public Output_section_data
     { return this->name_key == symbol->name_key; }
   };
 
-  typedef std::vector<int> Cu_vector;
+  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_;