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This changes the DWARF reader to share partial symtabs (or indices if they are available) across objfiles. This has a few parts. * If multiple objfiles backed by the same BFD can share partial symtabs (see below), a single dwarf2_per_bfd is created. It is stored in the per-bfd `dwarf2_per_bfd_bfd_data_key` registry. Multiple dwarf2_per_objfile objects will point to the same instance. The lifetime of these dwarf2_per_bfd objects is naturally handled. When all the objfiles using the BFD are destroyed, the BFD's refount drops to 0, which triggers the removal of the corresponding dwarf2_per_bfd object from the registry and its destruction. * If multiple objfiles backed by the same BFD can't share partial symtabs (see below), one dwarf2_per_bfd object is created for each objfile. Each dwarf2_per_objfile will point to their own instance of dwarf2_per_bfd. These instances of dwarf2_per_bfd are kept in a per-objfile registry, meaning that when the objfile gets destroyed, the dwarf2_per_bfd instance gets destroyed as well. * objfile::partial_symtabs is changed to be a shared_ptr again. This lets us stash a second reference in dwarf2_per_bfd; if the DWARF data is being shared, we can simply copy this value to the new objfile. * Two dwarf2_per_objfile objects backed by the same BFD may share a dwarf2_per_bfd instance if: * No other symbol reader has found symbols, and * No BFD section rqeuires relocation gdb/ChangeLog: YYYY-MM-DD Tom Tromey <tom@tromey.com> YYYY-MM-DD Simon Marchi <simon.marchi@efficios.com> * objfiles.h (struct objfile) <partial_symtabs>: Now a shared_ptr. * dwarf2/read.h (struct dwarf2_per_objfile) <partial_symtabs>: New member. * dwarf2/read.c (dwarf2_per_bfd_bfd_data_key, dwarf2_per_bfd_objfile_data_key>: New globals. (dwarf2_has_info): Use shared dwarf2_per_bfd if possible. (dwarf2_get_section_info): Use get_dwarf2_per_objfile. (dwarf2_initialize_objfile): Consider cases where per_bfd can be shared. (dwarf2_build_psymtabs): Set objfile::partial_symtabs and short-circuit when sharing. (dwarf2_build_psymtabs): Set dwarf2_per_objfile::partial_symtabs. (dwarf2_psymtab::expand_psymtab): Use free_cached_comp_units. Change-Id: I868c64448589102ab8cbb8f06c31a8de50a14004
README for GNU development tools This directory contains various GNU compilers, assemblers, linkers, debuggers, etc., plus their support routines, definitions, and documentation. If you are receiving this as part of a GDB release, see the file gdb/README. If with a binutils release, see binutils/README; if with a libg++ release, see libg++/README, etc. That'll give you info about this package -- supported targets, how to use it, how to report bugs, etc. It is now possible to automatically configure and build a variety of tools with one command. To build all of the tools contained herein, run the ``configure'' script here, e.g.: ./configure make To install them (by default in /usr/local/bin, /usr/local/lib, etc), then do: make install (If the configure script can't determine your type of computer, give it the name as an argument, for instance ``./configure sun4''. You can use the script ``config.sub'' to test whether a name is recognized; if it is, config.sub translates it to a triplet specifying CPU, vendor, and OS.) If you have more than one compiler on your system, it is often best to explicitly set CC in the environment before running configure, and to also set CC when running make. For example (assuming sh/bash/ksh): CC=gcc ./configure make A similar example using csh: setenv CC gcc ./configure make Much of the code and documentation enclosed is copyright by the Free Software Foundation, Inc. See the file COPYING or COPYING.LIB in the various directories, for a description of the GNU General Public License terms under which you can copy the files. REPORTING BUGS: Again, see gdb/README, binutils/README, etc., for info on where and how to report problems.