Target::new_output_section.
(Layout::attach_allocated_section_to_segment): Put large section
sections in a separate load segment with the large segment flag
set.
(Layout::segment_precedes): Sort large data segments after other
load segments.
(align_file_offset): New static function.
(Layout::set_segment_offsets): Use align_file_offset.
* output.h (class Output_section): Add is_small_section_ and
is_large_section_ fields.
(Output_section::is_small_section): New function.
(Output_section::set_is_small_section): New function.
(Output_section::is_large_section): New function.
(Output_section::set_is_large_section): New function.
(Output_section::is_large_data_section): New function.
(class Output_segment): Add is_large_data_segment_ field.
(Output_segment::is_large_data_segment): New function.
(Output_segment::set_is_large_data_segment): New function.
* output.cc (Output_section::Output_section): Initialize new
fields.
(Output_segment::Output_segment): Likewise.
(Output_segment::add_output_section): Add assertion that large
data sections always go in large data segments. Force small data
sections to the end of the list of data sections. Force small BSS
sections to the start of the list of BSS sections. For large BSS
sections to the end of the list of BSS sections.
* symtab.h (class Symbol): Declare is_common_shndx.
(Symbol::is_defined): Check Symbol::is_common_shndx.
(Symbol::is_common): Likewise.
(class Symbol_table): Define enum Commons_section_type. Update
declarations. Add small_commons_ and large_commons_ fields.
* symtab.cc (Symbol::is_common_shndx): New function.
(Symbol_table::Symbol_table): Initialize new fields.
(Symbol_table::add_from_object): Put small and large common
symbols in the right list.
(Symbol_table::sized_finalized_symbol): Check
Symbol::is_common_shndx.
(Symbol_table::sized_write_globals): Likewise.
* common.cc (Symbol_table::do_allocate_commons): Allocate new
common symbol lists. Don't call do_allocate_commons_list if the
list is empty.
(Symbol_table::do_allocate_commons_list): Remove is_tls
parameter. Add comons_section_type parameter. Change all
callers. Handle small and large common symbols.
* object.cc (Sized_relobj::do_finalize_local_symbols): Check
Symbol::is_common_shndx.
* resolve.cc (symbol_to_bits): Likewise.
* target.h (Target::small_common_shndx): New function.
(Target::small_common_section_flags): New function.
(Target::large_common_shndx): New function.
(Target::large_common_section_flags): New function.
(Target::new_output_section): New function.
(Target::Target_info): Add small_common_shndx, large_common_shndx,
small_common_section_flags, and large_common_section_flags
fields.
(Target::do_new_output_section): New virtual function.
* arm.cc (Target_arm::arm_info): Initialize new fields.
* i386.cc (Target_i386::i386_info): Likewise.
* powerpc.cc (Target_powerpc::powerpc_info) [all versions]:
Likewise.
* sparc.c (Target_sparc::sparc_info) [all versions]: Likewise.
* x86_64.cc (Target_x86_64::x86_64_info): Likewise.
(Target_x86_64::do_new_output_section): New function.
* configure.ac: Define conditional MCMODEL_MEDIUM.
* testsuite/Makefile.am (check_PROGRAMS): Add large.
(large_SOURCES, large_CFLAGS, large_DEPENDENCIES): Define.
(large_LDFLAGS): Define.
* testsuite/large.c: New file.
* testsuite/testfile.cc (Target_test::test_target_info):
Initialize new fields.
* configure, testsuite/Makefile.in: Rebuild.
* Makefile.am (CCFILES): Add gc.cc.
(HFILES): Add gc.h.
* Makefile.in: Regenerate.
* gold.cc (Gc_runner): New class.
(queue_initial_tasks): Call garbage collection related tasks
when corresponding options are invoked.
(queue_middle_gc_tasks): New function.
(queue_middle_tasks): Reorder tasks to allow relocs to be read and
processed early before laying out sections during garbage collection.
* gold.h (queue_middle_gc_tasks): New function.
(is_prefix_of): Move from "layout.cc".
* i386.cc (Target_i386::gc_process_relocs): New function.
* layout.cc (is_prefix_of): Remove. Move to "gold.h"
* main.cc (main): Create object of class "Garbage_collection".
* object.cc (Relobj::copy_symbols_data): New function.
(Relobj::is_section_name_included): New function.
(Sized_relobj::do_layout): Allow this function to be called twice
during garbage collection and defer layout of section during the
first call.
* object.h (Relobj::get_symbols_data): New function.
(Relobj::is_section_name_included): New function.
(Relobj::copy_symbols_data): New function.
(Relobj::set_symbols_data): New function.
(Relobj::get_relocs_data): New function.
(Relobj::set_relocs_data): New function.
(Relobj::is_output_section_offset_invalid): New pure virtual function.
(Relobj::gc_process_relocs): New function.
(Relobj::do_gc_process_relocs): New pure virtual function.
(Relobj::sd_): New data member.
(Sized_relobj::is_output_section_offset_invalid): New function.
(Sized_relobj::do_gc_process_relocs): New function.
* options.h (General_options::gc_sections): Modify to not be a no-op.
(General_options::print_gc_sections): New option.
* plugin.cc (Plugin_finish::run): Remove function call to
Plugin_manager::layout_deferred_objects. Move it to "gold.cc".
* powerpc.cc (Target_powerpc::gc_process_relocs): New function.
* reloc.cc (Read_relocs::run): Add task to process relocs and
determine unreferenced sections when doing garbage collection.
(Gc_process_relocs): New class.
(Sized_relobj::do_gc_process_relocs): New function.
(Sized_relobj::do_scan_relocs): Don't try to scan the relocs for
sections that are garbage collected.
* reloc.h (Gc_process_relocs): New class.
* sparc.cc (Target_sparc::gc_process_relocs): New function.
* symtab.cc (Symbol::should_add_dynsym_entry): Do not add entries for
symbols whose corresponding sections are garbage collected.
(Symbol_table::Symbol_table): Add new parameter for the garbage
collection object.
(Symbol_table::gc_mark_undef_symbols): New function.
(Symbol_table::gc_mark_symbol_for_shlib): New function.
(Symbol_table::gc_mark_dyn_syms): New function.
(Symbol_table::resolve): Do not treat symbols seen in dynamic objects
as garbage.
(Symbol_table::add_from_object): Likewise.
(Symbol_table::add_from_relobj): When building shared objects, do not
treat externally visible symbols as garbage.
(Symbol_table::sized_finalize_symbol): Do not check dynamic symbol
table information for static and relocatable links.
* symtab.h (Symbol_table::set_gc): New function.
(Symbol_table::gc): New function.
(Symbol_table::gc_mark_undef_symbols): New function.
(Symbol_table::gc_mark_symbol_for_shlib): New function.
(Symbol_table::gc_mark_dyn_syms): New function.
(Symbol_table::gc_): New data member.
* target.h (Sized_target::gc_process_relocs): New pure virtual
function.
* x86_64.cc (Target_x86_64::gc_process_relocs): New function.
* testsuite/testfile.cc (Target_test::gc_process_relocs): New function.
* target-select.h: Include <vector>.
(class Target_selector): Make machine_, size_, and is_big_endian_
fields const. Add bfd_name_ and instantiated_target_ fields.
(Target_selector::Target_selector): Add bfd_name parameter.
(Target_selector::recognize): Make non-virtual, call
do_recognize.
(Target_selector::recognize_by_name): Make non-virtual, call
do_recognize_by_name.
(Target_selector::supported_names): New function.
(Target_selector::bfd_name): New function.
(Target_selector::do_instantiate_target): New pure virtual
function.
(Target_selector::do_recognize): New virtual function.
(Target_selector::do_recognize_by_name): New virtual function.
(Target_selector::instantiate_target): New private function.
(supported_target_names): Declare.
* target-select.cc (Target_selector::Target_selector): Update for
new parameter and fields.
(select_target_by_name): Check that the name matches before
calling recognize_by_name.
(supported_target_names): New function.
* i386.cc (class Target_selector_i386): Update Target_selector
constructor call. Remove recognize and recognize_by_name. Add
do_instantiate_target.
* x86_64.cc (class Target_selector_x86_64): Likewise.
* testsuite/testfile.cc (class Target_selector_test): Update for
changes to Target_selector.
Ian Lance Taylor
Sriraman Tallam
Ian Lance Taylor