diff options
Diffstat (limited to 'gold/layout.cc')
| -rw-r--r-- | gold/layout.cc | 158 |
1 files changed, 62 insertions, 96 deletions
diff --git a/gold/layout.cc b/gold/layout.cc index efeaf65..76b6b2b 100644 --- a/gold/layout.cc +++ b/gold/layout.cc @@ -79,10 +79,10 @@ Layout::Layout(const General_options& options, Script_options* script_options) : options_(options), script_options_(script_options), namepool_(), sympool_(), dynpool_(), signatures_(), section_name_map_(), segment_list_(), section_list_(), - unattached_section_list_(), special_output_list_(), - section_headers_(NULL), tls_segment_(NULL), symtab_section_(NULL), - dynsym_section_(NULL), dynamic_section_(NULL), dynamic_data_(NULL), - eh_frame_section_(NULL), eh_frame_data_(NULL), + unattached_section_list_(), sections_are_attached_(false), + special_output_list_(), section_headers_(NULL), tls_segment_(NULL), + symtab_section_(NULL), dynsym_section_(NULL), dynamic_section_(NULL), + dynamic_data_(NULL), eh_frame_section_(NULL), eh_frame_data_(NULL), added_eh_frame_data_(false), eh_frame_hdr_section_(NULL), build_id_note_(NULL), group_signatures_(), output_file_size_(-1), input_requires_executable_stack_(false), @@ -234,7 +234,15 @@ Output_section* Layout::get_output_section(const char* name, Stringpool::Key name_key, elfcpp::Elf_Word type, elfcpp::Elf_Xword flags) { - const Key key(name_key, std::make_pair(type, flags)); + elfcpp::Elf_Xword lookup_flags = flags; + + // Ignoring SHF_WRITE and SHF_EXECINSTR here means that we combine + // read-write with read-only sections. Some other ELF linkers do + // not do this. FIXME: Perhaps there should be an option + // controlling this. + lookup_flags &= ~(elfcpp::SHF_WRITE | elfcpp::SHF_EXECINSTR); + + const Key key(name_key, std::make_pair(type, lookup_flags)); const std::pair<Key, Output_section*> v(key, NULL); std::pair<Section_name_map::iterator, bool> ins( this->section_name_map_.insert(v)); @@ -268,11 +276,7 @@ Layout::get_output_section(const char* name, Stringpool::Key name_key, Section_name_map::iterator p = this->section_name_map_.find(zero_key); if (p != this->section_name_map_.end()) - { - os = p->second; - if ((flags & elfcpp::SHF_ALLOC) != 0) - this->allocate_output_section(os, flags); - } + os = p->second; } } @@ -285,17 +289,22 @@ Layout::get_output_section(const char* name, Stringpool::Key name_key, // Pick the output section to use for section NAME, in input file // RELOBJ, with type TYPE and flags FLAGS. RELOBJ may be NULL for a -// linker created section. ADJUST_NAME is true if we should apply the -// standard name mappings in Layout::output_section_name. This will -// return NULL if the input section should be discarded. +// linker created section. IS_INPUT_SECTION is true if we are +// choosing an output section for an input section found in a input +// file. This will return NULL if the input section should be +// discarded. Output_section* Layout::choose_output_section(const Relobj* relobj, const char* name, elfcpp::Elf_Word type, elfcpp::Elf_Xword flags, - bool adjust_name) + bool is_input_section) { - // We should ignore some flags. FIXME: This will need some - // adjustment for ld -r. + // We should not see any input sections after we have attached + // sections to segments. + gold_assert(!is_input_section || !this->sections_are_attached_); + + // Some flags in the input section should not be automatically + // copied to the output section. flags &= ~ (elfcpp::SHF_INFO_LINK | elfcpp::SHF_LINK_ORDER | elfcpp::SHF_GROUP @@ -324,17 +333,7 @@ Layout::choose_output_section(const Relobj* relobj, const char* name, if (output_section_slot != NULL) { if (*output_section_slot != NULL) - { - // If the output section was created unallocated, and we - // are now allocating it, then we need to clear the - // address set in the constructor and remove it from the - // unattached section list. - if (((*output_section_slot)->flags() & elfcpp::SHF_ALLOC) == 0 - && (flags & elfcpp::SHF_ALLOC) != 0) - this->allocate_output_section(*output_section_slot, flags); - - return *output_section_slot; - } + return *output_section_slot; // We don't put sections found in the linker script into // SECTION_NAME_MAP_. That keeps us from getting confused @@ -356,7 +355,7 @@ Layout::choose_output_section(const Relobj* relobj, const char* name, // output section. size_t len = strlen(name); - if (adjust_name && !parameters->options().relocatable()) + if (is_input_section && !parameters->options().relocatable()) name = Layout::output_section_name(name, &len); Stringpool::Key name_key; @@ -550,16 +549,6 @@ Layout::layout_eh_frame(Sized_relobj<size, big_endian>* object, if (os == NULL) return NULL; - // On some targets gcc assumes that a read-only .eh_frame section - // will be merged with a read-write .eh_frame section. - if ((shdr.get_sh_flags() & elfcpp::SHF_WRITE) != 0 - && (os->flags() & elfcpp::SHF_WRITE) == 0) - { - elfcpp::Elf_Xword new_flags = os->flags() | elfcpp::SHF_WRITE; - this->write_enable_output_section(os, new_flags); - os->set_flags(new_flags); - } - if (this->eh_frame_section_ == NULL) { this->eh_frame_section_ = os; @@ -606,6 +595,8 @@ Layout::layout_eh_frame(Sized_relobj<size, big_endian>* object, reloc_shndx, reloc_type)) { + os->update_flags_for_input_section(shdr.get_sh_flags()); + // We found a .eh_frame section we are going to optimize, so now // we can add the set of optimized sections to the output // section. We need to postpone adding this until we've found a @@ -689,11 +680,6 @@ Layout::make_output_section(const char* name, elfcpp::Elf_Word type, this->section_list_.push_back(os); - if ((flags & elfcpp::SHF_ALLOC) == 0) - this->unattached_section_list_.push_back(os); - else - this->attach_to_segment(os, flags); - // The GNU linker by default sorts some sections by priority, so we // do the same. We need to know that this might happen before we // attach any input sections. @@ -704,14 +690,46 @@ Layout::make_output_section(const char* name, elfcpp::Elf_Word type, || strcmp(name, ".fini_array") == 0)) os->set_may_sort_attached_input_sections(); + // If we have already attached the sections to segments, then we + // need to attach this one now. This happens for sections created + // directly by the linker. + if (this->sections_are_attached_) + this->attach_section_to_segment(os); + return os; } +// Attach output sections to segments. This is called after we have +// seen all the input sections. + +void +Layout::attach_sections_to_segments() +{ + for (Section_list::iterator p = this->section_list_.begin(); + p != this->section_list_.end(); + ++p) + this->attach_section_to_segment(*p); + + this->sections_are_attached_ = true; +} + +// Attach an output section to a segment. + +void +Layout::attach_section_to_segment(Output_section* os) +{ + if ((os->flags() & elfcpp::SHF_ALLOC) == 0) + this->unattached_section_list_.push_back(os); + else + this->attach_allocated_section_to_segment(os); +} + // Attach an allocated output section to a segment. void -Layout::attach_to_segment(Output_section* os, elfcpp::Elf_Xword flags) +Layout::attach_allocated_section_to_segment(Output_section* os) { + elfcpp::Elf_Xword flags = os->flags(); gold_assert((flags & elfcpp::SHF_ALLOC) != 0); if (parameters->options().relocatable()) @@ -811,58 +829,6 @@ Layout::make_output_section_for_script(const char* name) return os; } -// We have to move an existing output section from the unallocated -// list to the allocated list. - -void -Layout::allocate_output_section(Output_section* os, elfcpp::Elf_Xword flags) -{ - os->reset_address_and_file_offset(); - - Section_list::iterator p = std::find(this->unattached_section_list_.begin(), - this->unattached_section_list_.end(), - os); - gold_assert(p != this->unattached_section_list_.end()); - this->unattached_section_list_.erase(p); - - this->attach_to_segment(os, flags); -} - -// We have to move an existing output section from the read-only -// segment to the writable segment. - -void -Layout::write_enable_output_section(Output_section* os, - elfcpp::Elf_Xword flags) -{ - gold_assert((os->flags() & elfcpp::SHF_WRITE) == 0); - gold_assert(os->type() == elfcpp::SHT_PROGBITS); - gold_assert((flags & elfcpp::SHF_WRITE) != 0); - gold_assert((flags & elfcpp::SHF_ALLOC) != 0); - - if (parameters->options().relocatable()) - return; - - if (this->script_options_->saw_sections_clause()) - return; - - Segment_list::iterator p; - for (p = this->segment_list_.begin(); - p != this->segment_list_.end(); - ++p) - { - if ((*p)->type() == elfcpp::PT_LOAD - && ((*p)->flags() & elfcpp::PF_W) == 0) - { - (*p)->remove_output_section(os); - break; - } - } - gold_assert(p != this->segment_list_.end()); - - this->attach_to_segment(os, flags); -} - // Return the number of segments we expect to see. size_t |