X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=gold%2Fscript-sections.cc;h=68387dbe9636d0a003fd83a2459c3414e47dab67;hb=refs%2Fheads%2Fconcurrent-displaced-stepping-2020-04-01;hp=c42827f4f094f3ea2f6b6b94a1b264a40aa97439;hpb=6f2750feaf2827ef8a1a0a5b2f90c1e9a6cabbd1;p=deliverable%2Fbinutils-gdb.git diff --git a/gold/script-sections.cc b/gold/script-sections.cc index c42827f4f0..68387dbe96 100644 --- a/gold/script-sections.cc +++ b/gold/script-sections.cc @@ -1,6 +1,6 @@ // script-sections.cc -- linker script SECTIONS for gold -// Copyright (C) 2008-2016 Free Software Foundation, Inc. +// Copyright (C) 2008-2020 Free Software Foundation, Inc. // Written by Ian Lance Taylor . // This file is part of gold. @@ -244,10 +244,10 @@ Memory_region::attributes_compatible(elfcpp::Elf_Xword flags, attrs &= ~ (attrs & - attrs); } while (attrs != 0); - + return match; } - + // Print a memory region. void @@ -313,6 +313,10 @@ class Orphan_section_placement bool find_place(Output_section*, Elements_iterator** pwhere); + // Update PLACE_LAST_ALLOC. + void + update_last_alloc(Elements_iterator where); + // Return the iterator being used for sections at the very end of // the linker script. Elements_iterator @@ -329,6 +333,7 @@ class Orphan_section_placement PLACE_TLS, PLACE_TLS_BSS, PLACE_BSS, + PLACE_LAST_ALLOC, PLACE_REL, PLACE_INTERP, PLACE_NONALLOC, @@ -368,6 +373,7 @@ Orphan_section_placement::Orphan_section_placement() this->initialize_place(PLACE_TLS, NULL); this->initialize_place(PLACE_TLS_BSS, NULL); this->initialize_place(PLACE_BSS, ".bss"); + this->initialize_place(PLACE_LAST_ALLOC, NULL); this->initialize_place(PLACE_REL, NULL); this->initialize_place(PLACE_INTERP, ".interp"); this->initialize_place(PLACE_NONALLOC, NULL); @@ -396,6 +402,15 @@ Orphan_section_placement::output_section_init(const std::string& name, bool first_init = this->first_init_; this->first_init_ = false; + // Remember the last allocated section. Any orphan bss sections + // will be placed after it. + if (os != NULL + && (os->flags() & elfcpp::SHF_ALLOC) != 0) + { + this->places_[PLACE_LAST_ALLOC].location = location; + this->places_[PLACE_LAST_ALLOC].have_location = true; + } + for (int i = 0; i < PLACE_MAX; ++i) { if (this->places_[i].name != NULL && this->places_[i].name == name) @@ -508,8 +523,13 @@ Orphan_section_placement::find_place(Output_section* os, case PLACE_RODATA: follow = PLACE_TEXT; break; + case PLACE_DATA: + follow = PLACE_RODATA; + if (!this->places_[PLACE_RODATA].have_location) + follow = PLACE_TEXT; + break; case PLACE_BSS: - follow = PLACE_DATA; + follow = PLACE_LAST_ALLOC; break; case PLACE_REL: follow = PLACE_TEXT; @@ -546,6 +566,20 @@ Orphan_section_placement::find_place(Output_section* os, return ret; } +// Update PLACE_LAST_ALLOC. +void +Orphan_section_placement::update_last_alloc(Elements_iterator elem) +{ + Elements_iterator prev = elem; + --prev; + if (this->places_[PLACE_LAST_ALLOC].have_location + && this->places_[PLACE_LAST_ALLOC].location == prev) + { + this->places_[PLACE_LAST_ALLOC].have_location = true; + this->places_[PLACE_LAST_ALLOC].location = elem; + } +} + // Return the iterator being used for sections at the very end of the // linker script. @@ -598,7 +632,7 @@ class Sections_element // Output_section_definition. virtual const char* output_section_name(const char*, const char*, Output_section***, - Script_sections::Section_type*, bool*) + Script_sections::Section_type*, bool*, bool) { return NULL; } // Initialize OSP with an output section. @@ -1503,7 +1537,7 @@ class Input_section_info private: // Input section, can be a relaxed section. Output_section::Input_section input_section_; - // Name of the section. + // Name of the section. std::string section_name_; // Section size. uint64_t size_; @@ -1524,18 +1558,69 @@ class Input_section_sorter operator()(const Input_section_info&, const Input_section_info&) const; private: + static unsigned long + get_init_priority(const char*); + Sort_wildcard filename_sort_; Sort_wildcard section_sort_; }; +// Return a relative priority of the section with the specified NAME +// (a lower value meand a higher priority), or 0 if it should be compared +// with others as strings. +// The implementation of this function is copied from ld/ldlang.c. + +unsigned long +Input_section_sorter::get_init_priority(const char* name) +{ + char* end; + unsigned long init_priority; + + // GCC uses the following section names for the init_priority + // attribute with numerical values 101 and 65535 inclusive. A + // lower value means a higher priority. + // + // 1: .init_array.NNNN/.fini_array.NNNN: Where NNNN is the + // decimal numerical value of the init_priority attribute. + // The order of execution in .init_array is forward and + // .fini_array is backward. + // 2: .ctors.NNNN/.dtors.NNNN: Where NNNN is 65535 minus the + // decimal numerical value of the init_priority attribute. + // The order of execution in .ctors is backward and .dtors + // is forward. + + if (strncmp(name, ".init_array.", 12) == 0 + || strncmp(name, ".fini_array.", 12) == 0) + { + init_priority = strtoul(name + 12, &end, 10); + return *end ? 0 : init_priority; + } + else if (strncmp(name, ".ctors.", 7) == 0 + || strncmp(name, ".dtors.", 7) == 0) + { + init_priority = strtoul(name + 7, &end, 10); + return *end ? 0 : 65535 - init_priority; + } + + return 0; +} + bool Input_section_sorter::operator()(const Input_section_info& isi1, const Input_section_info& isi2) const { + if (this->section_sort_ == SORT_WILDCARD_BY_INIT_PRIORITY) + { + unsigned long ip1 = get_init_priority(isi1.section_name().c_str()); + unsigned long ip2 = get_init_priority(isi2.section_name().c_str()); + if (ip1 != 0 && ip2 != 0 && ip1 != ip2) + return ip1 < ip2; + } if (this->section_sort_ == SORT_WILDCARD_BY_NAME || this->section_sort_ == SORT_WILDCARD_BY_NAME_BY_ALIGNMENT || (this->section_sort_ == SORT_WILDCARD_BY_ALIGNMENT_BY_NAME - && isi1.addralign() == isi2.addralign())) + && isi1.addralign() == isi2.addralign()) + || this->section_sort_ == SORT_WILDCARD_BY_INIT_PRIORITY) { if (isi1.section_name() != isi2.section_name()) return isi1.section_name() < isi2.section_name(); @@ -1595,6 +1680,7 @@ Output_section_element_input::set_section_addresses( typedef std::vector > Matching_sections; size_t input_pattern_count = this->input_section_patterns_.size(); + size_t bin_count = 1; bool any_patterns_with_sort = false; for (size_t i = 0; i < input_pattern_count; ++i) { @@ -1602,9 +1688,9 @@ Output_section_element_input::set_section_addresses( if (isp.sort != SORT_WILDCARD_NONE) any_patterns_with_sort = true; } - if (input_pattern_count == 0 || !any_patterns_with_sort) - input_pattern_count = 1; - Matching_sections matching_sections(input_pattern_count); + if (any_patterns_with_sort) + bin_count = input_pattern_count; + Matching_sections matching_sections(bin_count); // Look through the list of sections for this output section. Add // each one which matches to one of the elements of @@ -1614,7 +1700,7 @@ Output_section_element_input::set_section_addresses( while (p != input_sections->end()) { Relobj* relobj = p->relobj(); - unsigned int shndx = p->shndx(); + unsigned int shndx = p->shndx(); Input_section_info isi(*p); // Calling section_name and section_addralign is not very @@ -1661,11 +1747,11 @@ Output_section_element_input::set_section_addresses( break; } - if (i >= this->input_section_patterns_.size()) + if (i >= input_pattern_count) ++p; else { - if (!any_patterns_with_sort) + if (i >= bin_count) i = 0; matching_sections[i].push_back(isi); p = input_sections->erase(p); @@ -1679,7 +1765,7 @@ Output_section_element_input::set_section_addresses( // output section. uint64_t dot = *dot_value; - for (size_t i = 0; i < input_pattern_count; ++i) + for (size_t i = 0; i < bin_count; ++i) { if (matching_sections[i].empty()) continue; @@ -1699,16 +1785,16 @@ Output_section_element_input::set_section_addresses( p != matching_sections[i].end(); ++p) { - // Override the original address alignment if SUBALIGN is specified - // and is greater than the original alignment. We need to make a - // copy of the input section to modify the alignment. + // Override the original address alignment if SUBALIGN is specified. + // We need to make a copy of the input section to modify the + // alignment. Output_section::Input_section sis(p->input_section()); uint64_t this_subalign = sis.addralign(); if (!sis.is_input_section()) - sis.output_section_data()->finalize_data_size(); + sis.output_section_data()->finalize_data_size(); uint64_t data_size = sis.data_size(); - if (this_subalign < subalign) + if (subalign > 0) { this_subalign = subalign; sis.set_addralign(subalign); @@ -1826,6 +1912,10 @@ Output_section_element_input::print(FILE* f) const fprintf(f, "SORT_BY_ALIGNMENT(SORT_BY_NAME("); close_parens = 2; break; + case SORT_WILDCARD_BY_INIT_PRIORITY: + fprintf(f, "SORT_BY_INIT_PRIORITY("); + close_parens = 1; + break; default: gold_unreachable(); } @@ -1913,7 +2003,7 @@ class Output_section_definition : public Sections_element const char* output_section_name(const char* file_name, const char* section_name, Output_section***, Script_sections::Section_type*, - bool*); + bool*, bool); // Initialize OSP with an output section. void @@ -1973,7 +2063,7 @@ class Output_section_definition : public Sections_element void set_section_vma(Expression* address) { this->address_ = address; } - + void set_section_lma(Expression* address) { this->load_address_ = address; } @@ -1981,7 +2071,7 @@ class Output_section_definition : public Sections_element const std::string& get_section_name() const { return this->name_; } - + private: static const char* script_section_type_name(Script_section_type); @@ -2199,8 +2289,20 @@ Output_section_definition::output_section_name( const char* section_name, Output_section*** slot, Script_sections::Section_type* psection_type, - bool* keep) + bool* keep, + bool match_input_spec) { + // If the section is a linker-created output section, just look for a match + // on the output section name. + if (!match_input_spec && this->name_ != "/DISCARD/") + { + if (this->name_ != section_name) + return NULL; + *slot = &this->output_section_; + *psection_type = this->section_type(); + return this->name_.c_str(); + } + // Ask each element whether it matches NAME. for (Output_section_elements::const_iterator p = this->elements_.begin(); p != this->elements_.end(); @@ -2346,9 +2448,9 @@ Output_section_definition::set_section_addresses(Symbol_table* symtab, uint64_t old_load_address = *load_address; // If input section sorting is requested via --section-ordering-file or - // linker plugins, then do it here. This is important because we want + // linker plugins, then do it here. This is important because we want // any sorting specified in the linker scripts, which will be done after - // this, to take precedence. The final order of input sections is then + // this, to take precedence. The final order of input sections is then // guaranteed to be according to the linker script specification. if (this->output_section_ != NULL && this->output_section_->input_section_order_specified()) @@ -2407,6 +2509,35 @@ Output_section_definition::set_section_addresses(Symbol_table* symtab, this->output_section_->set_addralign(align); } + uint64_t subalign; + if (this->subalign_ == NULL) + subalign = 0; + else + { + Output_section* subalign_section; + subalign = this->subalign_->eval_with_dot(symtab, layout, true, + *dot_value, NULL, + &subalign_section, NULL, + false); + if (subalign_section != NULL) + gold_warning(_("subalign of section %s is not absolute"), + this->name_.c_str()); + + // Reserve a value of 0 to mean there is no SUBALIGN property. + if (subalign == 0) + subalign = 1; + + // The external alignment of the output section must be at least + // as large as that of the input sections. If there is no + // explicit ALIGN property, we set the output section alignment + // to match the input section alignment. + if (align < subalign || this->align_ == NULL) + { + align = subalign; + this->output_section_->set_addralign(align); + } + } + address = align_address(address, align); uint64_t start_address = address; @@ -2439,7 +2570,7 @@ Output_section_definition::set_section_addresses(Symbol_table* symtab, // The LMA address was explicitly set to the given region. laddr = lma_region->get_current_address()->eval(symtab, layout, false); - else + else { // We are not going to use the discovered lma_region, so // make sure that we do not update it in the code below. @@ -2491,21 +2622,6 @@ Output_section_definition::set_section_addresses(Symbol_table* symtab, this->evaluated_load_address_ = laddr; - uint64_t subalign; - if (this->subalign_ == NULL) - subalign = 0; - else - { - Output_section* subalign_section; - subalign = this->subalign_->eval_with_dot(symtab, layout, true, - *dot_value, NULL, - &subalign_section, NULL, - false); - if (subalign_section != NULL) - gold_warning(_("subalign of section %s is not absolute"), - this->name_.c_str()); - } - std::string fill; if (this->fill_ != NULL) { @@ -2931,9 +3047,9 @@ Orphan_output_section::set_section_addresses(Symbol_table*, Layout*, address = align_address(address, this->os_->addralign()); // If input section sorting is requested via --section-ordering-file or - // linker plugins, then do it here. This is important because we want + // linker plugins, then do it here. This is important because we want // any sorting specified in the linker scripts, which will be done after - // this, to take precedence. The final order of input sections is then + // this, to take precedence. The final order of input sections is then // guaranteed to be according to the linker script specification. if (this->os_ != NULL && this->os_->input_section_order_specified()) @@ -2967,7 +3083,7 @@ Orphan_output_section::set_section_addresses(Symbol_table*, Layout*, { uint64_t addralign = p->addralign(); if (!p->is_input_section()) - p->output_section_data()->finalize_data_size(); + p->output_section_data()->finalize_data_size(); uint64_t size = p->data_size(); address = align_address(address, addralign); this->os_->add_script_input_section(*p); @@ -3453,7 +3569,8 @@ Script_sections::output_section_name( const char* section_name, Output_section*** output_section_slot, Script_sections::Section_type* psection_type, - bool* keep) + bool* keep, + bool is_input_section) { for (Sections_elements::const_iterator p = this->sections_elements_->begin(); p != this->sections_elements_->end(); @@ -3461,7 +3578,8 @@ Script_sections::output_section_name( { const char* ret = (*p)->output_section_name(file_name, section_name, output_section_slot, - psection_type, keep); + psection_type, keep, + is_input_section); if (ret != NULL) { @@ -3477,12 +3595,37 @@ Script_sections::output_section_name( } } - // If we couldn't find a mapping for the name, the output section - // gets the name of the input section. - + // We have an orphan section. *output_section_slot = NULL; *psection_type = Script_sections::ST_NONE; + *keep = false; + General_options::Orphan_handling orphan_handling = + parameters->options().orphan_handling_enum(); + if (orphan_handling == General_options::ORPHAN_DISCARD) + return NULL; + if (orphan_handling == General_options::ORPHAN_ERROR) + { + if (file_name == NULL) + gold_error(_("unplaced orphan section '%s'"), section_name); + else + gold_error(_("unplaced orphan section '%s' from '%s'"), + section_name, file_name); + return NULL; + } + if (orphan_handling == General_options::ORPHAN_WARN) + { + if (file_name == NULL) + gold_warning(_("orphan section '%s' is being placed in section '%s'"), + section_name, section_name); + else + gold_warning(_("orphan section '%s' from '%s' is being placed " + "in section '%s'"), + section_name, file_name, section_name); + } + + // If we couldn't find a mapping for the name, the output section + // gets the name of the input section. return section_name; } @@ -3535,6 +3678,9 @@ Script_sections::place_orphan(Output_section* os) Sections_elements::iterator last = osp->last_place(); *where = this->sections_elements_->insert(last, orphan); } + + if ((os->flags() & elfcpp::SHF_ALLOC) != 0) + osp->update_last_alloc(*where); } // Set the addresses of all the output sections. Walk through all the @@ -3549,7 +3695,7 @@ Output_segment* Script_sections::set_section_addresses(Symbol_table* symtab, Layout* layout) { gold_assert(this->saw_sections_clause_); - + // Implement ONLY_IF_RO/ONLY_IF_RW constraints. These are a pain // for our representation. for (Sections_elements::iterator p = this->sections_elements_->begin(); @@ -3618,7 +3764,7 @@ Script_sections::set_section_addresses(Symbol_table* symtab, Layout* layout) Output_section* os = (*p)->get_output_section(); // Handle -Ttext, -Tdata and -Tbss options. We do this by looking for - // the special sections by names and doing dot assignments. + // the special sections by names and doing dot assignments. if (use_tsection_options && os != NULL && (os->flags() & elfcpp::SHF_ALLOC) != 0) @@ -3647,7 +3793,7 @@ Script_sections::set_section_addresses(Symbol_table* symtab, Layout* layout) (*p)->set_section_addresses(symtab, layout, &dot_value, &dot_alignment, &load_address); - } + } if (this->phdrs_elements_ != NULL) { @@ -3834,7 +3980,7 @@ Script_sections::create_segments(Layout* layout, uint64_t dot_alignment) layout->get_allocated_sections(§ions); // Sort the sections by address. - std::stable_sort(sections.begin(), sections.end(), + std::stable_sort(sections.begin(), sections.end(), Sort_output_sections(this->sections_elements_)); this->create_note_and_tls_segments(layout, §ions); @@ -3844,10 +3990,10 @@ Script_sections::create_segments(Layout* layout, uint64_t dot_alignment) Output_segment* first_seg = NULL; Output_segment* current_seg = NULL; bool is_current_seg_readonly = true; - Layout::Section_list::iterator plast = sections.end(); uint64_t last_vma = 0; uint64_t last_lma = 0; uint64_t last_size = 0; + bool in_bss = false; for (Layout::Section_list::iterator p = sections.begin(); p != sections.end(); ++p) @@ -3874,7 +4020,7 @@ Script_sections::create_segments(Layout* layout, uint64_t dot_alignment) // skipping a page. need_new_segment = true; } - else if (is_bss_section(*plast) && !is_bss_section(*p)) + else if (in_bss && !is_bss_section(*p)) { // A non-BSS section can not follow a BSS section in the // same segment. @@ -3906,6 +4052,7 @@ Script_sections::create_segments(Layout* layout, uint64_t dot_alignment) if (first_seg == NULL) first_seg = current_seg; is_current_seg_readonly = true; + in_bss = false; } current_seg->add_output_section_to_load(layout, *p, seg_flags); @@ -3913,7 +4060,9 @@ Script_sections::create_segments(Layout* layout, uint64_t dot_alignment) if (((*p)->flags() & elfcpp::SHF_WRITE) != 0) is_current_seg_readonly = false; - plast = p; + if (is_bss_section(*p) && size > 0) + in_bss = true; + last_vma = vma; last_lma = lma; last_size = size; @@ -4161,7 +4310,7 @@ Script_sections::attach_sections_using_phdrs_clause(Layout* layout) // Output sections in the script which do not list segments are // attached to the same set of segments as the immediately preceding // output section. - + String_list* phdr_names = NULL; bool load_segments_only = false; for (Sections_elements::const_iterator p = this->sections_elements_->begin(); @@ -4206,7 +4355,7 @@ Script_sections::attach_sections_using_phdrs_clause(Layout* layout) // filtering. if (old_phdr_names != phdr_names) load_segments_only = false; - + // If this is an orphan section--one that was not explicitly // mentioned in the linker script--then it should not inherit // any segment type other than PT_LOAD. Otherwise, e.g., the @@ -4403,6 +4552,7 @@ Script_sections::release_segments() ++p) (*p)->release_segment(); } + this->segments_created_ = false; } // Print the SECTIONS clause to F for debugging.