In order to get around the optimizer and newer compiler warnings
about shift counts, the overflow checking code had resorted to
some messy shifting, and with the never-before-seen instantiations
of the template functions, we were still running afoul of the
compiler checks.
This patch replaces those messy shift sequences with a simple
class template that provides the min and max limits for any
bit size up to 64, with a specialization for 64 that prevents
the compiler from complaining.
gold/
PR gold/19577
* reloc.h (Limits): New class.
(Bits::has_overflow32): Use min/max values from Limits.
(Bits::has_unsigned_overflow32): Likewise.
(Bits::has_signed_unsigned_overflow32): Likewise.
(Bits::has_overflow): Likewise.
(Bits::has_unsigned_overflow): Likewise.
(Bits::has_signed_unsigned_overflow64): Likewise.
The problem here is that x32 is really using 64-bit addressing,
while pretending to be 32-bit. Even though the object file format
is 32-bit, we need to do the overflow checking with 64-bit
arithmetic (because that's what the hardware will be using).
This patch overrides the pcrela32_check functions in reloc.h
with target-specific versions that do 64-bit checking.
I've also updated the test case to use -Tdata instead of adding
a huge .space directive, to reduce the size of the .o files.
gold/
PR gold/19567
* reloc.h (Relocate_functions::Overflow_check): Add comments.
* x86_64.cc (X86_64_relocate_functions): New class.
(Target_x86_64::Relocate::relocate): Use the new class.
* testsuite/Makefile.am (x86_64_overflow_pc32): Add -Tdata option.
(x32_overflow_pc32): New test case.
* testsuite/Makefile.in: Regenerate.
* testsuite/x32_overflow_pc32.sh: New script.
* testsuite/x86_64_overflow_pc32.s: Remove .space directive.
Some linker code editing needs to change multiple insns. In some
cases multiple relocations are involved and it is not sufficient to
make the changes independently as relocations are processed, because
doing so might lead to a partial edit. So in order to safely edit we
need all the relocations available in relocate(). Also, to emit
edited relocs corresponding to the edited code sequence we need some
way to pass information from relocate() to relocate_relocs(),
particularly if the edit depends on insns. We can't modify input
relocs in relocate() as they are mmapped PROT_READ, nor it is
particularly clean to write relocs to the output at that stage. So
add a Relocatable_relocs* field to relinfo to mark edited relocs.
Given that relocate is passed the raw reloc pointer, it makes sense to
remove the rel/rela parameter and r_type too. However, that means the
mips relocate() needs to know whether SHT_REL or SHT_RELA relocs are
being processed. So add a rel_type for mips, which also has the
benefit of removing relocate() overloading there.
This patch adds the infrastructure without making use of it.
Note that relinfo->rr will be NULL if not outputting relocations.
* object.h (struct Relocate_info): Add "rr".
* reloc.h (Relocatable_relocs::set_strategy): New accessor.
* reloc.cc (Sized_relobj_file::do_relocate_sections): Init
relinfo.rr for relocate_section and relocate_relocs.
* powerpc.cc (relocate): Add rel_type and preloc parameters.
Delete rela and r_type params, instead recalculate these from
preloc.
(relocate_relocs): Delete Relocatable_relocs* param, instead
use relinfo->rr.
* aarch64.cc: Likewise.
* arm.cc: Likewise.
* i386.cc: Likewise.
* mips.cc: Likewise.
* s390.cc: Likewise.
* sparc.cc: Likewise.
* target.h: Likewise.
* tilegx.cc: Likewise.
* x86_64.cc: Likewise.
* testsuite/testfile.cc: Likewise.
* target-reloc.h (relocate_section): Adjust to suit.
(apply_relocation, relocate_relocs): Likewise.
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.
* Makefile.am: Add gdb-index.cc, gdb-index.h.
* Makefile.in: Regenerate.
* dwarf_reader.cc (Sized_elf_reloc_mapper::do_initialize): New function.
(Sized_elf_reloc_mapper::symbol_section): New function.
(Sized_elf_reloc_mapper::do_get_reloc_target): New function.
(make_elf_reloc_mapper): New function.
(Dwarf_abbrev_table::clear_abbrev_codes): New function.
(Dwarf_abbrev_table::do_read_abbrevs): New function.
(Dwarf_abbrev_table::do_get_abbrev): New function.
(Dwarf_ranges_table::read_ranges_table): New function.
(Dwarf_ranges_table::read_range_list): New function.
(Dwarf_pubnames_table::read_section): New function.
(Dwarf_pubnames_table::read_header): New function.
(Dwarf_pubnames_table::next_name): New function.
(Dwarf_die::Dwarf_die): New function.
(Dwarf_die::read_attributes): New function.
(Dwarf_die::skip_attributes): New function.
(Dwarf_die::set_name): New function.
(Dwarf_die::set_linkage_name): New function.
(Dwarf_die::attribute): New function.
(Dwarf_die::string_attribute): New function.
(Dwarf_die::int_attribute): New function.
(Dwarf_die::uint_attribute): New function.
(Dwarf_die::ref_attribute): New function.
(Dwarf_die::child_offset): New function.
(Dwarf_die::sibling_offset): New function.
(Dwarf_info_reader::check_buffer): New function.
(Dwarf_info_reader::parse): New function.
(Dwarf_info_reader::do_parse): New function.
(Dwarf_info_reader::do_read_string_table): New function.
(Dwarf_info_reader::lookup_reloc): New function.
(Dwarf_info_reader::get_string): New function.
(Dwarf_info_reader::visit_compilation_unit): New function.
(Dwarf_info_reader::visit_type_unit): New function.
(Sized_dwarf_line_info::Sized_dwarf_line_info): Use
Sized_elf_reloc_mapper.
(Sized_dwarf_line_info::symbol_section): Remove function.
(Sized_dwarf_line_info::read_relocs): Use Sized_elf_reloc_mapper.
(Sized_dwarf_line_info::read_line_mappings): Remove object
parameter, adjust callers.
(Sized_dwarf_line_info::format_file_lineno): Fix type of cast.
* dwarf_reader.h: Include <sys/types.h>.
(class Track_relocs): Remove forward declaration.
(class Elf_reloc_mapper): New class.
(class Sized_elf_reloc_mapper): New class.
(class Dwarf_abbrev_table): New class.
(class Dwarf_range_list): New class.
(class Dwarf_ranges_table): New class.
(class Dwarf_pubnames_table): New class.
(class Dwarf_die): New class.
(class Dwarf_info_reader): New class.
(Sized_dwarf_line_info::read_line_mappings): Remove object parameter.
(Sized_dwarf_line_info::symbol_section): Remove member function.
* dynobj.h (Sized_dynobj::do_section_contents): Refactor code from
base class.
* gdb-index.cc: New source file.
* gdb-index.h: New source file.
* incremental.cc (Sized_relobj_incr::do_layout): Track .debug_info
and .debug_types sections, call Layout::add_to_gdb_index.
(Sized_relobj_incr::do_section_name): Implement.
(Sized_relobj_incr::do_section_contents): Adjust parameter list and
return type; Implement.
(Sized_incr_dynobj::do_section_contents): Adjust parameter list and
return type.
* incremental.h (Sized_relobj_incr::do_section_contents): Adjust
parameter list and return type.
(Sized_incr_dynobj::do_section_contents): Likewise.
* layout.cc: Include gdb-index.h.
(Layout::Layout): Initialize gdb_index_data_.
(Layout::init_fixed_output_section): Check for .gdb_index section.
(Layout::add_to_gdb_index): New function. Instantiate.
* layout.h: Add forward declaration for class Gdb_index.
(Layout::add_to_gdb_index): New member function.
(Layout::gdb_index_data_): New data member.
* main.cc: Include gdb-index.h.
(main): Print statistics for gdb index.
* object.cc (Object::section_contents): Move code into
do_section_contents.
(need_decompressed_section): Check for sections needed when building
gdb index.
(build_compressed_section_map): Likewise.
(Sized_relobj_file::do_read_symbols): Need local symbols when building
gdb index.
(Sized_relobj_file::do_layout): Track .debug_info and .debug_types
sections; call Layout::add_to_gdb_index.
(Sized_relobj_file::do_decompressed_section_contents): Call
do_section_contents directly.
* object.h (Object::do_section_contents): Adjust parameter list and
return type.
(Object::do_decompressed_section_contents): Call do_section_contents
directly.
(Sized_relobj_file::do_section_contents): Adjust parameter list and
return type.
* options.h (class General_options): Add --gdb-index option.
* plugin.cc (Sized_pluginobj::do_section_contents): Adjust parameter
list and return type.
* plugin.h (Sized_pluginobj::do_section_contents): Likewise.
* reloc.h (Track_relocs::checkpoint): New function.
(Track_relocs::reset): New function.
* testsuite/Makefile.am (gdb_index_test_1.sh, gdb_index_test_2.sh):
New test cases.
* testsuite/Makefile.in: Regenerate.
* testsuite/gdb_index_test.cc: New test source file.
* testsuite/gdb_index_test_1.sh: New test source file.
* testsuite/gdb_index_test_2.sh: New test source file.
* arm.cc (Arm_relocate_functions::abs8,
Arm_relocate_functions::abs16): Use
Bits::has_signed_unsigned_overflow32.
(Arm_relocate_functions::thm_abs8): Correct range of
overflow check.
* reloc.h (Bits class): Change minimum number of bits from 0 to 1
in assertions.
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.
track_relocs_type_ field.
* dwarf_reader.cc (Sized_dwarf_line_info::Sized_dwarf_line_info):
Set track_relocs_type_.
(Sized_dwarf_line_info::process_one_opcode): Ignore the section
contents when using RELA relocs.
(Sized_dwarf_line_info::read_relocs): Add the reloc addend to
reloc_map_.
* reloc.cc (Track_relocs::next_addend): New function.
* reloc.h (class Track_relocs): Declare next_addend.
Read_relocs task.
(queue_middle_tasks): Likewise, and also for Scan_relocs. Run
Allocate_commons_task first.
* reloc.cc (Read_relocs::run): Pass next_blocker_ down to next
task, rather than symtab_lock_.
(Gc_process_relocs::~Gc_process_relocs): New function.
(Gc_process_relocs::is_runnable): Check this_blocker_.
(Gc_process_relocs::locks): Use next_blocker_ rather than
blocker_.
(Scan_relocs::~Scan_relocs): New function.
(Scan_relocs::is_runnable): Check this_blocker_ rather than
symtab_lock_.
(Scan_relocs::locks): Drop symtab_lock_ and blocker_. Add
next_blocker_.
* reloc.h (class Read_relocs): Drop symtab_lock_ and blocker_
fields. Add this_blocker_ and next_blocker_ fields. Adjust
constructor accordingly.
(class Gc_process_relocs): Likewise.
(class Scan_relocs): Likewise.
* common.h (class Allocate_commons_task): Remove symtab_lock_
field, and corresponding constructor parameter.
* common.cc (Allocate_commons_tasK::is_runnable): Remove use of
symtab_lock_.
(Allocate_commons_task::locks): Likewise.
* 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.
* copy-relocs.h: New file.
* reloc.cc: Remove Copy_relocs code.
* reloc.h: Likewise.
* reloc-types.h (struct Reloc_types) [both versions]: Add
get_reloc_addend_noerror.
* output.h (class Output_data_reloc<elfcpp::SHT_REL>): Add
variants of add_global which take an addend which must be zero.
* i386.cc: Include "copy-relocs.h".
(class Target_i386): Change type of copy_relocs_ to variable,
update initializer.
(Target_i386::copy_reloc): Rewrite to pass to Copy_relocs class.
Change all callers.
(Target_i386::do_finalize_sections): Change handling of
copy_relocs_.
* sparc.cc: Include "copy-relocs.h".
(class Target_sparc): Change type of copy_relocs_ to variable,
update initializer.
(Target_sparc::copy_reloc): Rewrite to pass to Copy_relocs class.
Change all callers.
(Target_sparc::do_finalize_sections): Change handling of
copy_relocs_.
* x86_64.cc: Include "copy-relocs.h".
(class Target_x86_64): Change type of copy_relocs_ to variable,
update initializer.
(Target_x86_64::copy_reloc): Rewrite to pass to Copy_relocs
class. Change all callers.
(Target_x86_64::do_finalize_sections): Change handling of
copy_relocs_.
* Makefile.am (CCFILES): Add copy-relocs.cc.
(HFILES): Add copy-relocs.h.
