During --icf processing, gold was incorrectly processing the relocation
addend for references to items in a merge section. PC-relative references
and other forms of reference with a biased base address require a
non-section local symbol, where the addend is purely the bias.
gold/
PR gold/20642
PR gold/22820
* gc.h (gc_process_relocs): Flag STT_SECTION symbols in symvec.
* icf.cc (get_section_contents): For merge sections, ignore the
addend for relocations against non-section symbols.
When checking a R_ARM_TARGET[12] relocation, we need a valid target
pointer, but the garbage collection code was passing a NULL instead.
The previous fix for this bug fixed the call to
scan.global_reloc_may_be_function_pointer, but missed the similar
call to scan.local_reloc_may_be_function_pointer.
gold/
PR gold/23046
* gc.h (gc_process_relocs): Pass target to
scan.local_reloc_may_be_function_pointer.
When checking a R_ARM_TARGET[12] relocation, we need a valid target
pointer, but the garbage collection code was passing a NULL instead.
gold/
PR gold/23046
* gc.h (gc_process_relocs): Pass target to
scan.global_reloc_may_be_function_pointer.
gold/
* x86_64.cc (Target_x86_64::do_can_check_for_function_pointers):
Return true even when building pie binaries.
(Target_x86_64::possible_function_pointer_reloc): Check opcode
for R_X86_64_PC32 relocations.
(Target_x86_64::local_reloc_may_be_function_pointer): Pass
extra arguments to local_reloc_may_be_function_pointer.
(Target_x86_64::global_reloc_may_be_function_pointer): Likewise.
* gc.h (gc_process_relocs): Add check for STT_FUNC.
* testsuite/Makefile.am (icf_safe_pie_test): New test case.
* testsuite/Makefile.in: Regenerate.
* testsuite/icf_safe_pie_test.sh: New shell script.
For MIPS-64, the r_info field in the relocation format is
replaced by several individual fields, including r_sym and
r_type. To enable support for this format, I've refactored
target-independent code to remove almost all uses of the r_info
field. (I've left alone a couple of routines used only for
incremental linking, which I can update if/when the MIPS target
adds support for incremental linking.)
For routines that are already templated on a Classify_reloc class
(namely, gc_process_relocs, relocate_section, and
relocate_relocs), I've extended the Classify_reloc interface to
include sh_type (which no longer needs to be a separate template
parameter) as well as get_r_sym() and get_r_type() methods for
extracting the r_sym and r_type fields. For
scan_relocatable_relocs, I've extended the
Default_scan_relocatable_relocs class by converting it to a class
template with Classify_reloc as a template parameter. For the
remaining routines that need to access r_sym, I've added a
virtual Target::get_r_sym() method with an override for the MIPS
target.
In elfcpp, I've added Mips64_rel, etc., accessor classes and
corresponding internal data structures. The MIPS target uses
these new classes within its own Mips_classify_reloc class.
The Mips64_ accessor classes also expose the r_ssym, r_type2,
and r_type3 fields from the relocation.
These changes should be functionally the same for all but the
MIPS target.
elfcpp/
* elfcpp.h (Mips64_rel, Mips64_rel_write): New classes.
(Mips64_rela, Mips64_rela_write): New classes.
* elfcpp_internal.h (Mips64_rel_data, Mips64_rela_data): New structs.
gold/
* gc.h (get_embedded_addend_size): Remove sh_type parameter.
(gc_process_relocs): Remove sh_type template parameter.
Use Classify_reloc to access r_sym, r_type, and r_addend fields.
* object.h (Sized_relobj_file::split_stack_adjust): Add target
parameter.
(Sized_relobj_file::split_stack_adjust_reltype): Likewise.
* reloc-types.h (Reloc_types::copy_reloc_addend): (SHT_REL and SHT_RELA
specializations) Remove.
* reloc.cc (Emit_relocs_strategy): Rename and move to target-reloc.h.
(Sized_relobj_file::emit_relocs_scan): Call Target::emit_relocs_scan().
(Sized_relobj_file::emit_relocs_scan_reltype): Remove.
(Sized_relobj_file::split_stack_adjust): Add target parameter.
Adjust all callers.
(Sized_relobj_file::split_stack_adjust_reltype): Likewise. Call
Target::get_r_sym() to get r_sym field from relocations.
(Track_relocs::next_symndx): Call Target::get_r_sym().
* target-reloc.h (scan_relocs): Remove sh_type template parameter;
add Classify_reloc template parameter. Use for accessing r_sym and
r_type.
(relocate_section): Likewise.
(Default_classify_reloc): New class (renamed and moved from reloc.cc).
(Default_scan_relocatable_relocs): Remove sh_type template parameter.
(Default_scan_relocatable_relocs::Reltype): New typedef.
(Default_scan_relocatable_relocs::reloc_size): New const.
(Default_scan_relocatable_relocs::sh_type): New const.
(Default_scan_relocatable_relocs::get_r_sym): New method.
(Default_scan_relocatable_relocs::get_r_type): New method.
(Default_emit_relocs_strategy): New class.
(scan_relocatable_relocs): Replace sh_type template parameter with
Scan_relocatable_relocs class. Use it to access r_sym and r_type
fields.
(relocate_relocs): Replace sh_type template parameter with
Classify_reloc class. Use it to access r_sym and r_type fields.
* target.h (Target::is_call_to_non_split): Replace r_type parameter
with pointer to relocation. Adjust all callers.
(Target::do_is_call_to_non_split): Likewise.
(Target::emit_relocs_scan): New virtual method.
(Sized_target::get_r_sym): New virtual method.
* target.cc (Target::do_is_call_to_non_split): Replace r_type parameter
with pointer to relocation.
* aarch64.cc (Target_aarch64::emit_relocs_scan): New method.
(Target_aarch64::Relocatable_size_for_reloc): Remove.
(Target_aarch64::gc_process_relocs): Use Default_classify_reloc.
(Target_aarch64::scan_relocs): Likewise.
(Target_aarch64::relocate_section): Likewise.
(Target_aarch64::Relocatable_size_for_reloc::get_size_for_reloc):
Remove.
(Target_aarch64::scan_relocatable_relocs): Use Default_classify_reloc.
(Target_aarch64::relocate_relocs): Use Default_classify_reloc.
* arm.cc (Target_arm::Arm_scan_relocatable_relocs): Remove sh_type
template parameter.
(Target_arm::emit_relocs_scan): New method.
(Target_arm::Relocatable_size_for_reloc): Replace with...
(Target_arm::Classify_reloc): ...this.
(Target_arm::gc_process_relocs): Use Classify_reloc.
(Target_arm::scan_relocs): Likewise.
(Target_arm::relocate_section): Likewise.
(Target_arm::scan_relocatable_relocs): Likewise.
(Target_arm::relocate_relocs): Likewise.
* i386.cc (Target_i386::emit_relocs_scan): New method.
(Target_i386::Relocatable_size_for_reloc): Replace with...
(Target_i386::Classify_reloc): ...this.
(Target_i386::gc_process_relocs): Use Classify_reloc.
(Target_i386::scan_relocs): Likewise.
(Target_i386::relocate_section): Likewise.
(Target_i386::scan_relocatable_relocs): Likewise.
(Target_i386::relocate_relocs): Likewise.
* mips.cc (Mips_scan_relocatable_relocs): Remove sh_type template
parameter.
(Mips_reloc_types): New class template.
(Mips_classify_reloc): New class template.
(Target_mips::Reltype): New typedef.
(Target_mips::Relatype): New typedef.
(Target_mips::emit_relocs_scan): New method.
(Target_mips::get_r_sym): New method.
(Target_mips::Relocatable_size_for_reloc): Replace with
Mips_classify_reloc.
(Target_mips::copy_reloc): Use Mips_classify_reloc.
(Target_mips::gc_process_relocs): Likewise.
(Target_mips::scan_relocs): Likewise.
(Target_mips::relocate_section): Likewise.
(Target_mips::scan_relocatable_relocs): Likewise.
(Target_mips::relocate_relocs): Likewise.
(mips_get_size_for_reloc): New function, factored out from
Relocatable_size_for_reloc::get_size_for_reloc.
(Target_mips::Scan::local): Use Mips_classify_reloc.
(Target_mips::Scan::global): Likewise.
(Target_mips::Relocate::relocate): Likewise.
* powerpc.cc (Target_powerpc::emit_relocs_scan): New method.
(Target_powerpc::Relocatable_size_for_reloc): Remove.
(Target_powerpc::gc_process_relocs): Use Default_classify_reloc.
(Target_powerpc::scan_relocs): Likewise.
(Target_powerpc::relocate_section): Likewise.
(Powerpc_scan_relocatable_reloc): Convert to class template.
(Powerpc_scan_relocatable_reloc::Reltype): New typedef.
(Powerpc_scan_relocatable_reloc::reloc_size): New const.
(Powerpc_scan_relocatable_reloc::sh_type): New const.
(Powerpc_scan_relocatable_reloc::get_r_sym): New method.
(Powerpc_scan_relocatable_reloc::get_r_type): New method.
(Target_powerpc::scan_relocatable_relocs): Use
Powerpc_scan_relocatable_reloc.
(Target_powerpc::relocate_relocs): Use Default_classify_reloc.
* s390.cc (Target_s390::emit_relocs_scan): New method.
(Target_s390::Relocatable_size_for_reloc): Remove.
(Target_s390::gc_process_relocs): Use Default_classify_reloc.
(Target_s390::scan_relocs): Likewise.
(Target_s390::relocate_section): Likewise.
(Target_s390::Relocatable_size_for_reloc::get_size_for_reloc):
Remove.
(Target_s390::scan_relocatable_relocs): Use Default_classify_reloc.
(Target_s390::relocate_relocs): Use Default_classify_reloc.
* sparc.cc (Target_sparc::emit_relocs_scan): New method.
(Target_sparc::Relocatable_size_for_reloc): Remove.
(Target_sparc::gc_process_relocs): Use Default_classify_reloc.
(Target_sparc::scan_relocs): Likewise.
(Target_sparc::relocate_section): Likewise.
(Target_sparc::Relocatable_size_for_reloc::get_size_for_reloc):
Remove.
(Target_sparc::scan_relocatable_relocs): Use Default_classify_reloc.
(Target_sparc::relocate_relocs): Use Default_classify_reloc.
* tilegx.cc (Target_tilegx::emit_relocs_scan): New method.
(Target_tilegx::Relocatable_size_for_reloc): Remove.
(Target_tilegx::gc_process_relocs): Use Default_classify_reloc.
(Target_tilegx::scan_relocs): Likewise.
(Target_tilegx::relocate_section): Likewise.
(Target_tilegx::Relocatable_size_for_reloc::get_size_for_reloc):
Remove.
(Target_tilegx::scan_relocatable_relocs): Use Default_classify_reloc.
(Target_tilegx::relocate_relocs): Use Default_classify_reloc.
* x86_64.cc (Target_x86_64::emit_relocs_scan): New method.
(Target_x86_64::Relocatable_size_for_reloc): Remove.
(Target_x86_64::gc_process_relocs): Use Default_classify_reloc.
(Target_x86_64::scan_relocs): Likewise.
(Target_x86_64::relocate_section): Likewise.
(Target_x86_64::Relocatable_size_for_reloc::get_size_for_reloc):
Remove.
(Target_x86_64::scan_relocatable_relocs): Use Default_classify_reloc.
(Target_x86_64::relocate_relocs): Use Default_classify_reloc.
* testsuite/testfile.cc (Target_test::emit_relocs_scan): New method.
(Sized_target::gc_add_reference, do_gc_add_reference): New functions.
* gc.h (gc_process_relocs): Call target gc_add_reference.
* gold.cc (queue_middle_tasks): Use gc_mark_symbol on start sym.
* symtab.cc (Symbol_table::gc_mark_undef_symbols): Use gc_mark_symbol.
(Symbol_table::gc_mark_symbol): Call target gc_mark_symbol. Remove
unnecessary cast.
* powerpc.cc (Powerpc_relobj::get_opd_ent): Rearrange parameters
to cater for when we don't need code offset. Update use.
(Powerpc_relobj::access_from_map_, opd_valid_): New vars.
(Powerpc_relobj::access_from_map, add_reference, opd_valid,
set_opd_valid): New functions.
(Target_powerpc::do_gc_add_reference): New function.
(Target_powerpc::gc_process_relocs): Call gc()->add_reference on
stashed refs.
(Target_powerpc::do_gc_mark_symbol): New function.
pointer.
(Stub_addend_reader::operator()): Declare Arm_relocate_functions
as a class, not a struct.
(Target_arm::scan_span_for_cortex_a8_erratum): Likewise.
(Target_arm::apply_cortex_a8_workaround): Likewise.
* gc.h: Declare Reloc_types as a struct, not a class.
* object.h: Declare Symbols_data as a struct.
* reloc.h: Declare Read_relocs_data as a struct.
* target.h: Declare Relocate_info as a struct.
info; adjust display of GOT entries.
* incremental.cc (Sized_incremental_binary::setup_readers): Allocate
vector of input objects; remove file_status_.
(Sized_incremental_binary::do_reserve_layout): Remove file_status_.
(Sized_incremental_binary::do_process_got_plt): Adjust calls to
got_plt reader; call target hooks to reserve GOT entries.
(Output_section_incremental_inputs::set_final_data_size): Adjust size
of input file info header and GOT info entry.
(Output_section_incremental_inputs::write_info_blocks): Write dynamic
relocation info.
(Got_plt_view_info::got_descriptor): Remove.
(Got_plt_view_info::sym_index): New data member.
(Got_plt_view_info::input_index): New data member.
(Local_got_offset_visitor::visit): Write input file index.
(Global_got_offset_visitor::visit): Write 0 for input file index.
(Global_symbol_visitor_got_plt::operator()): Replace got_descriptor
with sym_index and input_index.
(Output_section_incremental_inputs::write_got_plt): Adjust size of
incremental info GOT entry; replace got_descriptor with input_index.
(Sized_relobj_incr::Sized_relobj_incr): Adjust initializers; record
map from input file index to object.
(Sized_relobj_incr::do_layout): Replace direct data member reference
with accessor function.
(Sized_relobj_incr::do_for_all_local_got_entries): Move to base class.
* incremental.h (Incremental_input_entry_reader::get_symbol_offset):
Adjust size of input file info header.
(Incremental_input_entry_reader::get_first_dyn_reloc): New function.
(Incremental_input_entry_reader::get_dyn_reloc_count): New function.
(Incremental_input_entry_reader::get_input_section): Adjust size of
input file info header.
(Incremental_got_plt_reader::Incremental_got_plt_reader): Adjust size
of incremental info GOT entry.
(Incremental_got_plt_reader::get_got_desc): Remove.
(Incremental_got_plt_reader::get_got_symndx): New function.
(Incremental_got_plt_reader::get_got_input_index): New function.
(Sized_incremental_binary::Sized_incremental_binary): Remove
file_status_; add input_objects_.
(Sized_incremental_binary::~Sized_incremental_binary): Remove.
(Sized_incremental_binary::set_file_is_unchanged): Remove.
(Sized_incremental_binary::file_is_unchanged): Remove.
(Sized_incremental_binary::set_input_object): New function.
(Sized_incremental_binary::input_object): New function.
(Sized_incremental_binary::file_status_): Remove.
(Sized_incremental_binary::input_objects_): New data member.
(Sized_relobj_incr): Rename Sized_incr_relobj to this; adjust all
references.
(Sized_relobj_incr::invalid_address): Move to base class.
(Sized_relobj_incr::is_output_section_offset_invalid): Move to base
class.
(Sized_relobj_incr::do_output_section_offset): Likewise.
(Sized_relobj_incr::do_for_all_local_got_entries): Likewise.
(Sized_relobj_incr::section_offsets_): Likewise.
* object.cc (Sized_relobj::do_for_all_local_got_entries): New
function.
(Sized_relobj_file::Sized_relobj_file): Remove local_got_offsets_.
(Sized_relobj_file::layout_section): Replace refs to section_offsets_
with accessor function.
(Sized_relobj_file::do_layout): Likewise.
(Sized_relobj_file::do_layout_deferred_sections): Likewise.
(Sized_relobj_file::do_for_all_local_got_entries): Move to base class.
(Sized_relobj_file::compute_final_local_value): Replace refs to
section_offsets_ with accessor function.
(Sized_relobj_file::do_finalize_local_symbols): Likewise.
* object.h (Relobj::Relobj): Initialize new data members.
(Relobj::add_dyn_reloc): New function.
(Relobj::first_dyn_reloc): New function.
(Relobj::dyn_reloc_count): New function.
(Relobj::first_dyn_reloc_): New data member.
(Relobj::dyn_reloc_count_): New data member.
(Sized_relobj): Rename Sized_relobj_base to this; adjust all
references.
(Sized_relobj::Address): New typedef.
(Sized_relobj::invalid_address): Move here from child class.
(Sized_relobj::Sized_relobj): Initialize new data members.
(Sized_relobj::sized_relobj): New function.
(Sized_relobj::is_output_section_offset_invalid): Move here from
child class.
(Sized_relobj::get_output_section_offset): Likewise.
(Sized_relobj::local_has_got_offset): Likewise.
(Sized_relobj::local_got_offset): Likewise.
(Sized_relobj::set_local_got_offset): Likewise.
(Sized_relobj::do_for_all_local_got_entries): Likewise.
(Sized_relobj::clear_got_offsets): New function.
(Sized_relobj::section_offsets): Move here from child class.
(Sized_relobj::do_output_section_offset): Likewise.
(Sized_relobj::do_set_section_offset): Likewise.
(Sized_relobj::Local_got_offsets): Likewise.
(Sized_relobj::local_got_offsets_): Likewise.
(Sized_relobj::section_offsets_): Likewise.
(Sized_relobj_file): Rename Sized_relobj to this; adjust all
references.
(Sized_relobj_file::is_output_section_offset_invalid): Move to base
class.
(Sized_relobj_file::sized_relobj): New function
(Sized_relobj_file::local_has_got_offset): Move to base class.
(Sized_relobj_file::local_got_offset): Likewise.
(Sized_relobj_file::set_local_got_offset): Likewise.
(Sized_relobj_file::get_output_section_offset): Likewise.
(Sized_relobj_file::do_for_all_local_got_entries): Likewise.
(Sized_relobj_file::do_output_section_offset): Likewise.
(Sized_relobj_file::do_set_section_offset): Likewise.
(Sized_relobj_file::Local_got_offsets): Likewise.
(Sized_relobj_file::local_got_offsets_): Likewise.
(Sized_relobj_file::section_offsets_): Likewise.
* output.cc (Output_reloc::Output_reloc): Adjust type of relobj
(all constructors).
(set_needs_dynsym_index): Convert relobj to derived class pointer.
(Output_reloc::get_symbol_index): Likewise.
(Output_reloc::local_section_offset): Likewise.
(Output_reloc::get_address): Likewise.
(Output_reloc::symbol_value): Likewise.
(Output_data_got::reserve_slot): Move to class definition.
(Output_data_got::reserve_local): New function.
(Output_data_got::reserve_slot_for_global): Remove.
(Output_data_got::reserve_global): New function.
* output.h (Output_reloc::Output_reloc): Adjust type of relobj
(all constructors, two instantiations).
(Output_reloc::get_relobj): New function (two instantiations).
(Output_reloc::u1_.relobj, Output_reloc::u2_.relobj): Adjust type.
(Output_data_reloc_base::add): Convert relobj to derived class pointer.
(Output_data_reloc::add_global): Adjust type of relobj.
(Output_data_reloc::add_global_relative): Likewise.
(Output_data_reloc::add_symbolless_global_addend): Likewise.
(Output_data_reloc::add_local): Likewise.
(Output_data_reloc::add_local_relative): Likewise.
(Output_data_reloc::add_symbolless_local_addend): Likewise.
(Output_data_reloc::add_local_section): Likewise.
(Output_data_reloc::add_output_section): Likewise.
(Output_data_reloc::add_absolute): Likewise.
(Output_data_reloc::add_target_specific): Likewise.
(Output_data_got::reserve_slot): Move definition here.
(Output_data_got::reserve_local): New function.
(Output_data_got::reserve_global): New function.
* reloc.cc (Sized_relobj_file::do_read_relocs): Replace refs to
section_offsets_ with accessor function.
(Sized_relobj_file::write_sections): Likewise.
(Sized_relobj_file::do_relocate_sections): Likewise.
* target.h (Sized_target::reserve_local_got_entry): New function.
(Sized_target::reserve_global_got_entry): New function.
* x86_64.cc (Target_x86_64::reserve_local_got_entry): New function.
(Target_x86_64::reserve_global_got_entry): New function.
(Target_x86_64::init_got_plt_for_update): Create rela_dyn section.
paramter to the call to gold::gc_process_relocs.
* i386.cc (Target_i386<big_endian>::gc_process_relocs): Add template
paramter to the call to gold::gc_process_relocs.
* x86_64.cc (Target_x86_64<big_endian>::gc_process_relocs): Add template
parameter to the call to gold::gc_process_relocs.
* powerpc.cc (Target_powerpc<big_endian>::gc_process_relocs): Add
template parameter to the call to gold::gc_process_relocs.
* sparc.cc (Target_sparc<big_endian>::gc_process_relocs): Add template
paramter to the call to gold::gc_process_relocs.
* gc.h (get_embedded_addend_size): New function.
(gc_process_relocs): Save the size of the reloc for use by ICF.
* icf.cc (get_section_contents): Get the addend from the text section
for SHT_REL relocation sections.
* icf.h (Icf::Reloc_addend_size_info): New typedef.
(Icf::Reloc_info): Add new member reloc_addend_size_info.
* int_encoding.h (read_from_pointer): New overloaded function.
* testsuite/Makefile.am (icf_sht_rel_addend_test): New test.
* testsuite/icf_sht_rel_addend_test.sh: New file.
* testsuite/icf_sht_rel_addend_test_1.cc: New file.
* testsuite/icf_sht_rel_addend_test_2.cc: New file.
* gc.h (gc_process_relocs): Pass information on relocs pointing to
sections that are not ordinary to icf.
* icf.cc (get_section_contents): Handle relocation pointing to section
with no object or shndx information.
* testsuite/Makefile.am: Remove icf_virtual_function_folding_test.sh
* testsuite/Makefile.in: Regenerate.
* testsuite/icf_virtual_function_folding_test.cc: Remove printf.
* testsuite/icf_virtual_function_folding_test.sh: Delete file.
* gc.h (gc_process_relocs): Change vectors to point to the new list.
Add reloc offset information.
* icf.cc (get_section_contents): Change iterators to point to the new
vectors. Add reloc offset information to the contents.
* icf.h (Icf::Sections_reachable_info): New typedef.
(Icf::Sections_reachable_list): New typedef.
(Icf::Offset_info): New typedef.
(Icf::Reloc_info): New struct typedef.
(Icf::Reloc_info_list): New typedef.
(Icf::symbol_reloc_list): Delete method.
(Icf::addend_reloc_list): Delete method.
(Icf::section_reloc_list): Delete method.
(Icf::reloc_info_list): New method.
(Icf::reloc_info_list_): New member.
* arm.cc (Scan::local_reloc_may_be_function_pointer): New function.
(Scan::global_reloc_may_be_function_pointer): New function.
* sparc.cc (Scan::local_reloc_may_be_function_pointer): New function.
(Scan::global_reloc_may_be_function_pointer): New function.
* powerpc.cc (Scan::local_reloc_may_be_function_pointer): New function.
(Scan::global_reloc_may_be_function_pointer): New function.
* i386.cc (Scan::local_reloc_may_be_function_pointer): New function.
(Scan::global_reloc_may_be_function_pointer): New function.
* x86_64.cc (Scan::local_reloc_may_be_function_pointer): New function.
(Scan::global_reloc_may_be_function_pointer): New function.
(Scan::possible_function_pointer_reloc): New function.
(Target_x86_64::can_check_for_function_pointers): New function.
* gc.h (gc_process_relocs): Scan relocation types to determine if
function pointers were taken for targets that support it.
* icf.cc (Icf::find_identical_sections): Include functions for
folding in safe ICF whose pointer is not taken.
* icf.h (Secn_fptr_taken_set): New typedef.
(fptr_section_id_): New member.
(section_has_function_pointers): New function.
(set_section_has_function_pointers): New function.
(check_section_for_function_pointers): New function.
* options.h: Fix comment for safe ICF option.
* target.h (can_check_for_function_pointers): New function.
* testsuite/Makefile.am: Add icf_safe_so_test test case.
Modify icf_safe_test for X86-64.
* testsuite/Makefile.in: Regenerate.
* testsuite/icf_safe_so_test.cc: New file.
* testsuite/icf_safe_so_test.sh: New file.
* testsuite/icf_safe_test.cc (kept_func_3): New function.
(main): Change to take pointer to function kept_func_3.
* testsuite/icf_safe_test.sh (arch_specific_safe_fold): Check if safe
folding is done correctly for X86-64.
* arm.cc (Target_arm::Arm_input_section_map): Change key type from
Input_section_specifier to Section_id.
(Target_arm::new_arm_input_section: Adjust code for change of key
type.
(Target_arm::find_arm_input_section): Ditto.
* gc.h (object.h): Include for Section_id nand Section_id_hash.
(Section_id): Remove.
(Garbage_collection::Section_id_hash): Remove.
* icf.h (object.h): Include for Section_id nand Section_id_hash.
(Section_id): Remove.
(Icf::Section_id_hash): Remove.
* object.h (Section_id, Const_section_id, Section_id_hash,
Const_section_id_hash): New type definitions.
* output.cc (Output_section::add_relaxed_input_section): Change to
use Const_section_id instead of Input_section_specifier as key type.
(Output_section::add_merge_input_section): Ditto.
(Output_section::build_relaxation_map): Change to use Section_id
instead of Input_section_specifier as key type.
(Output_section::convert_input_sections_in_list_to_relaxed_sections):
Ditto.
(Output_section::convert_input_sections_to_relaxed_sections): Change
to use Const_section_id instead of Input_section_specifier as key type.
(Output_section::find_merge_section): Ditto.
(Output_section::find_relaxed_input_section): Ditto.
* output.h (Input_section_specifier): Remove class.
(Output_section::Output_section_data_by_input_section_map): Change
key type to Const_section_id.
(Output_section::Output_relaxed_input_section_by_input_section_map):
Ditto.
(Output_section::Relaxation_map): Change key type to Section_id.
* arm.cc (Arm_relobj::do_gc_process_relocs): New method.
(Target_arm::do_finalize_sections): Define special EXIDX section
symbols only if referenced.
* gc.h (Garbage_collection::add_reference): New method.
(gc_process_relocs): Use Garbage_collection::add_reference to avoid
code duplication.
(Garbage_collection::cident_sections): New function.
(Garbage_collection::add_cident_section): New function.
(Garbage_collection::cident_sections_): New member.
(gc_process_relocs): Add references to sections whose names are C
identifiers.
* gold.h (cident_section_start_prefix): New constant.
(cident_section_stop_prefix): New constant.
(is_cident): New function.
* layout.cc (Layout::define_section_symbols): Replace string constants
with the newly defined constants.
* object.cc (Sized_relobj::do_layout): Track sections whose names are
C identifiers.
* testsuite/Makefile.am: Add gc_orphan_section_test.
* testsuite/Makefile.in: Regenerate.
* testsuite/gc_orphan_section_test.cc: New file.
* testsuite/gc_orphan_section_test.sh: New file.
check for .text or .gnu.linkonce.t sections.
* icf.cc (Icf::find_identical_sections): Ditto.
Change the detection for mangled function name within the section
name.
* icf.h (is_section_foldable_candidate): New function.
function.
* gold.cc (queue_initial_tasks): Likewise.
(queue_middle_tasks): Likewise.
* object.cc (do_layout): Likewise.
* symtab.cc (is_section_folded): Likewise.
* main.cc (main): Likewise.
* reloc.cc (Read_relocs::run): Likewise.
(Sized_relobj::do_scan_relocs): Likewise.
* icf.cc (is_function_ctor_or_dtor): New function.
(Icf::find_identical_sections): Check if function is ctor or dtor when
safe icf is chosen.
* options.h (General_options::icf): Change option to be an enum.
(Icf_status): New enum.
(icf_enabled): New method.
(icf_safe_folding): New method.
(set_icf_status): New method.
(icf_status_): New variable.
* (options.cc) (General_options::finalize): Set icf_status_.
* testsuite/Makefile.am: Add commands to build icf_safe_test. Modify
icf_test and icf_keep_unique_test to use the --icf enum flag.
* testsuite/icf_safe_test.sh: New file.
* testsuite/icf_safe_test.cc: New file.
* 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.
