| // script-sections.cc -- linker script SECTIONS for gold |
| |
| // Copyright 2008 Free Software Foundation, Inc. |
| // Written by Ian Lance Taylor <iant@google.com>. |
| |
| // This file is part of gold. |
| |
| // This program is free software; you can redistribute it and/or modify |
| // it under the terms of the GNU General Public License as published by |
| // the Free Software Foundation; either version 3 of the License, or |
| // (at your option) any later version. |
| |
| // This program is distributed in the hope that it will be useful, |
| // but WITHOUT ANY WARRANTY; without even the implied warranty of |
| // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| // GNU General Public License for more details. |
| |
| // You should have received a copy of the GNU General Public License |
| // along with this program; if not, write to the Free Software |
| // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, |
| // MA 02110-1301, USA. |
| |
| #include "gold.h" |
| |
| #include <cstring> |
| #include <algorithm> |
| #include <list> |
| #include <map> |
| #include <string> |
| #include <vector> |
| #include <fnmatch.h> |
| |
| #include "parameters.h" |
| #include "object.h" |
| #include "layout.h" |
| #include "output.h" |
| #include "script-c.h" |
| #include "script.h" |
| #include "script-sections.h" |
| |
| // Support for the SECTIONS clause in linker scripts. |
| |
| namespace gold |
| { |
| |
| // An element in a SECTIONS clause. |
| |
| class Sections_element |
| { |
| public: |
| Sections_element() |
| { } |
| |
| virtual ~Sections_element() |
| { } |
| |
| // Record that an output section is relro. |
| virtual void |
| set_is_relro() |
| { } |
| |
| // Create any required output sections. The only real |
| // implementation is in Output_section_definition. |
| virtual void |
| create_sections(Layout*) |
| { } |
| |
| // Add any symbol being defined to the symbol table. |
| virtual void |
| add_symbols_to_table(Symbol_table*) |
| { } |
| |
| // Finalize symbols and check assertions. |
| virtual void |
| finalize_symbols(Symbol_table*, const Layout*, uint64_t*) |
| { } |
| |
| // Return the output section name to use for an input file name and |
| // section name. This only real implementation is in |
| // Output_section_definition. |
| virtual const char* |
| output_section_name(const char*, const char*, Output_section***) |
| { return NULL; } |
| |
| // Return whether to place an orphan output section after this |
| // element. |
| virtual bool |
| place_orphan_here(const Output_section *, bool*, bool*) const |
| { return false; } |
| |
| // Set section addresses. This includes applying assignments if the |
| // the expression is an absolute value. |
| virtual void |
| set_section_addresses(Symbol_table*, Layout*, uint64_t*, uint64_t*) |
| { } |
| |
| // Check a constraint (ONLY_IF_RO, etc.) on an output section. If |
| // this section is constrained, and the input sections do not match, |
| // return the constraint, and set *POSD. |
| virtual Section_constraint |
| check_constraint(Output_section_definition**) |
| { return CONSTRAINT_NONE; } |
| |
| // See if this is the alternate output section for a constrained |
| // output section. If it is, transfer the Output_section and return |
| // true. Otherwise return false. |
| virtual bool |
| alternate_constraint(Output_section_definition*, Section_constraint) |
| { return false; } |
| |
| // Get the list of segments to use for an allocated section when |
| // using a PHDRS clause. If this is an allocated section, return |
| // the Output_section, and set *PHDRS_LIST (the first parameter) to |
| // the list of PHDRS to which it should be attached. If the PHDRS |
| // were not specified, don't change *PHDRS_LIST. When not returning |
| // NULL, set *ORPHAN (the second parameter) according to whether |
| // this is an orphan section--one that is not mentioned in the |
| // linker script. |
| virtual Output_section* |
| allocate_to_segment(String_list**, bool*) |
| { return NULL; } |
| |
| // Look for an output section by name and return the address, the |
| // load address, the alignment, and the size. This is used when an |
| // expression refers to an output section which was not actually |
| // created. This returns true if the section was found, false |
| // otherwise. The only real definition is for |
| // Output_section_definition. |
| virtual bool |
| get_output_section_info(const char*, uint64_t*, uint64_t*, uint64_t*, |
| uint64_t*) const |
| { return false; } |
| |
| // Return the associated Output_section if there is one. |
| virtual Output_section* |
| get_output_section() const |
| { return NULL; } |
| |
| // Print the element for debugging purposes. |
| virtual void |
| print(FILE* f) const = 0; |
| }; |
| |
| // An assignment in a SECTIONS clause outside of an output section. |
| |
| class Sections_element_assignment : public Sections_element |
| { |
| public: |
| Sections_element_assignment(const char* name, size_t namelen, |
| Expression* val, bool provide, bool hidden) |
| : assignment_(name, namelen, val, provide, hidden) |
| { } |
| |
| // Add the symbol to the symbol table. |
| void |
| add_symbols_to_table(Symbol_table* symtab) |
| { this->assignment_.add_to_table(symtab); } |
| |
| // Finalize the symbol. |
| void |
| finalize_symbols(Symbol_table* symtab, const Layout* layout, |
| uint64_t* dot_value) |
| { |
| this->assignment_.finalize_with_dot(symtab, layout, *dot_value, NULL); |
| } |
| |
| // Set the section address. There is no section here, but if the |
| // value is absolute, we set the symbol. This permits us to use |
| // absolute symbols when setting dot. |
| void |
| set_section_addresses(Symbol_table* symtab, Layout* layout, |
| uint64_t* dot_value, uint64_t*) |
| { |
| this->assignment_.set_if_absolute(symtab, layout, true, *dot_value); |
| } |
| |
| // Print for debugging. |
| void |
| print(FILE* f) const |
| { |
| fprintf(f, " "); |
| this->assignment_.print(f); |
| } |
| |
| private: |
| Symbol_assignment assignment_; |
| }; |
| |
| // An assignment to the dot symbol in a SECTIONS clause outside of an |
| // output section. |
| |
| class Sections_element_dot_assignment : public Sections_element |
| { |
| public: |
| Sections_element_dot_assignment(Expression* val) |
| : val_(val) |
| { } |
| |
| // Finalize the symbol. |
| void |
| finalize_symbols(Symbol_table* symtab, const Layout* layout, |
| uint64_t* dot_value) |
| { |
| // We ignore the section of the result because outside of an |
| // output section definition the dot symbol is always considered |
| // to be absolute. |
| Output_section* dummy; |
| *dot_value = this->val_->eval_with_dot(symtab, layout, true, *dot_value, |
| NULL, &dummy); |
| } |
| |
| // Update the dot symbol while setting section addresses. |
| void |
| set_section_addresses(Symbol_table* symtab, Layout* layout, |
| uint64_t* dot_value, uint64_t* load_address) |
| { |
| Output_section* dummy; |
| *dot_value = this->val_->eval_with_dot(symtab, layout, false, *dot_value, |
| NULL, &dummy); |
| *load_address = *dot_value; |
| } |
| |
| // Print for debugging. |
| void |
| print(FILE* f) const |
| { |
| fprintf(f, " . = "); |
| this->val_->print(f); |
| fprintf(f, "\n"); |
| } |
| |
| private: |
| Expression* val_; |
| }; |
| |
| // An assertion in a SECTIONS clause outside of an output section. |
| |
| class Sections_element_assertion : public Sections_element |
| { |
| public: |
| Sections_element_assertion(Expression* check, const char* message, |
| size_t messagelen) |
| : assertion_(check, message, messagelen) |
| { } |
| |
| // Check the assertion. |
| void |
| finalize_symbols(Symbol_table* symtab, const Layout* layout, uint64_t*) |
| { this->assertion_.check(symtab, layout); } |
| |
| // Print for debugging. |
| void |
| print(FILE* f) const |
| { |
| fprintf(f, " "); |
| this->assertion_.print(f); |
| } |
| |
| private: |
| Script_assertion assertion_; |
| }; |
| |
| // An element in an output section in a SECTIONS clause. |
| |
| class Output_section_element |
| { |
| public: |
| // A list of input sections. |
| typedef std::list<std::pair<Relobj*, unsigned int> > Input_section_list; |
| |
| Output_section_element() |
| { } |
| |
| virtual ~Output_section_element() |
| { } |
| |
| // Return whether this element requires an output section to exist. |
| virtual bool |
| needs_output_section() const |
| { return false; } |
| |
| // Add any symbol being defined to the symbol table. |
| virtual void |
| add_symbols_to_table(Symbol_table*) |
| { } |
| |
| // Finalize symbols and check assertions. |
| virtual void |
| finalize_symbols(Symbol_table*, const Layout*, uint64_t*, Output_section**) |
| { } |
| |
| // Return whether this element matches FILE_NAME and SECTION_NAME. |
| // The only real implementation is in Output_section_element_input. |
| virtual bool |
| match_name(const char*, const char*) const |
| { return false; } |
| |
| // Set section addresses. This includes applying assignments if the |
| // the expression is an absolute value. |
| virtual void |
| set_section_addresses(Symbol_table*, Layout*, Output_section*, uint64_t, |
| uint64_t*, Output_section**, std::string*, |
| Input_section_list*) |
| { } |
| |
| // Print the element for debugging purposes. |
| virtual void |
| print(FILE* f) const = 0; |
| |
| protected: |
| // Return a fill string that is LENGTH bytes long, filling it with |
| // FILL. |
| std::string |
| get_fill_string(const std::string* fill, section_size_type length) const; |
| }; |
| |
| std::string |
| Output_section_element::get_fill_string(const std::string* fill, |
| section_size_type length) const |
| { |
| std::string this_fill; |
| this_fill.reserve(length); |
| while (this_fill.length() + fill->length() <= length) |
| this_fill += *fill; |
| if (this_fill.length() < length) |
| this_fill.append(*fill, 0, length - this_fill.length()); |
| return this_fill; |
| } |
| |
| // A symbol assignment in an output section. |
| |
| class Output_section_element_assignment : public Output_section_element |
| { |
| public: |
| Output_section_element_assignment(const char* name, size_t namelen, |
| Expression* val, bool provide, |
| bool hidden) |
| : assignment_(name, namelen, val, provide, hidden) |
| { } |
| |
| // Add the symbol to the symbol table. |
| void |
| add_symbols_to_table(Symbol_table* symtab) |
| { this->assignment_.add_to_table(symtab); } |
| |
| // Finalize the symbol. |
| void |
| finalize_symbols(Symbol_table* symtab, const Layout* layout, |
| uint64_t* dot_value, Output_section** dot_section) |
| { |
| this->assignment_.finalize_with_dot(symtab, layout, *dot_value, |
| *dot_section); |
| } |
| |
| // Set the section address. There is no section here, but if the |
| // value is absolute, we set the symbol. This permits us to use |
| // absolute symbols when setting dot. |
| void |
| set_section_addresses(Symbol_table* symtab, Layout* layout, Output_section*, |
| uint64_t, uint64_t* dot_value, Output_section**, |
| std::string*, Input_section_list*) |
| { |
| this->assignment_.set_if_absolute(symtab, layout, true, *dot_value); |
| } |
| |
| // Print for debugging. |
| void |
| print(FILE* f) const |
| { |
| fprintf(f, " "); |
| this->assignment_.print(f); |
| } |
| |
| private: |
| Symbol_assignment assignment_; |
| }; |
| |
| // An assignment to the dot symbol in an output section. |
| |
| class Output_section_element_dot_assignment : public Output_section_element |
| { |
| public: |
| Output_section_element_dot_assignment(Expression* val) |
| : val_(val) |
| { } |
| |
| // Finalize the symbol. |
| void |
| finalize_symbols(Symbol_table* symtab, const Layout* layout, |
| uint64_t* dot_value, Output_section** dot_section) |
| { |
| *dot_value = this->val_->eval_with_dot(symtab, layout, true, *dot_value, |
| *dot_section, dot_section); |
| } |
| |
| // Update the dot symbol while setting section addresses. |
| void |
| set_section_addresses(Symbol_table* symtab, Layout* layout, Output_section*, |
| uint64_t, uint64_t* dot_value, Output_section**, |
| std::string*, Input_section_list*); |
| |
| // Print for debugging. |
| void |
| print(FILE* f) const |
| { |
| fprintf(f, " . = "); |
| this->val_->print(f); |
| fprintf(f, "\n"); |
| } |
| |
| private: |
| Expression* val_; |
| }; |
| |
| // Update the dot symbol while setting section addresses. |
| |
| void |
| Output_section_element_dot_assignment::set_section_addresses( |
| Symbol_table* symtab, |
| Layout* layout, |
| Output_section* output_section, |
| uint64_t, |
| uint64_t* dot_value, |
| Output_section** dot_section, |
| std::string* fill, |
| Input_section_list*) |
| { |
| uint64_t next_dot = this->val_->eval_with_dot(symtab, layout, false, |
| *dot_value, *dot_section, |
| dot_section); |
| if (next_dot < *dot_value) |
| gold_error(_("dot may not move backward")); |
| if (next_dot > *dot_value && output_section != NULL) |
| { |
| section_size_type length = convert_to_section_size_type(next_dot |
| - *dot_value); |
| Output_section_data* posd; |
| if (fill->empty()) |
| posd = new Output_data_zero_fill(length, 0); |
| else |
| { |
| std::string this_fill = this->get_fill_string(fill, length); |
| posd = new Output_data_const(this_fill, 0); |
| } |
| output_section->add_output_section_data(posd); |
| } |
| *dot_value = next_dot; |
| } |
| |
| // An assertion in an output section. |
| |
| class Output_section_element_assertion : public Output_section_element |
| { |
| public: |
| Output_section_element_assertion(Expression* check, const char* message, |
| size_t messagelen) |
| : assertion_(check, message, messagelen) |
| { } |
| |
| void |
| print(FILE* f) const |
| { |
| fprintf(f, " "); |
| this->assertion_.print(f); |
| } |
| |
| private: |
| Script_assertion assertion_; |
| }; |
| |
| // We use a special instance of Output_section_data to handle BYTE, |
| // SHORT, etc. This permits forward references to symbols in the |
| // expressions. |
| |
| class Output_data_expression : public Output_section_data |
| { |
| public: |
| Output_data_expression(int size, bool is_signed, Expression* val, |
| const Symbol_table* symtab, const Layout* layout, |
| uint64_t dot_value, Output_section* dot_section) |
| : Output_section_data(size, 0), |
| is_signed_(is_signed), val_(val), symtab_(symtab), |
| layout_(layout), dot_value_(dot_value), dot_section_(dot_section) |
| { } |
| |
| protected: |
| // Write the data to the output file. |
| void |
| do_write(Output_file*); |
| |
| // Write the data to a buffer. |
| void |
| do_write_to_buffer(unsigned char*); |
| |
| // Write to a map file. |
| void |
| do_print_to_mapfile(Mapfile* mapfile) const |
| { mapfile->print_output_data(this, _("** expression")); } |
| |
| private: |
| template<bool big_endian> |
| void |
| endian_write_to_buffer(uint64_t, unsigned char*); |
| |
| bool is_signed_; |
| Expression* val_; |
| const Symbol_table* symtab_; |
| const Layout* layout_; |
| uint64_t dot_value_; |
| Output_section* dot_section_; |
| }; |
| |
| // Write the data element to the output file. |
| |
| void |
| Output_data_expression::do_write(Output_file* of) |
| { |
| unsigned char* view = of->get_output_view(this->offset(), this->data_size()); |
| this->write_to_buffer(view); |
| of->write_output_view(this->offset(), this->data_size(), view); |
| } |
| |
| // Write the data element to a buffer. |
| |
| void |
| Output_data_expression::do_write_to_buffer(unsigned char* buf) |
| { |
| Output_section* dummy; |
| uint64_t val = this->val_->eval_with_dot(this->symtab_, this->layout_, |
| true, this->dot_value_, |
| this->dot_section_, &dummy); |
| |
| if (parameters->target().is_big_endian()) |
| this->endian_write_to_buffer<true>(val, buf); |
| else |
| this->endian_write_to_buffer<false>(val, buf); |
| } |
| |
| template<bool big_endian> |
| void |
| Output_data_expression::endian_write_to_buffer(uint64_t val, |
| unsigned char* buf) |
| { |
| switch (this->data_size()) |
| { |
| case 1: |
| elfcpp::Swap_unaligned<8, big_endian>::writeval(buf, val); |
| break; |
| case 2: |
| elfcpp::Swap_unaligned<16, big_endian>::writeval(buf, val); |
| break; |
| case 4: |
| elfcpp::Swap_unaligned<32, big_endian>::writeval(buf, val); |
| break; |
| case 8: |
| if (parameters->target().get_size() == 32) |
| { |
| val &= 0xffffffff; |
| if (this->is_signed_ && (val & 0x80000000) != 0) |
| val |= 0xffffffff00000000LL; |
| } |
| elfcpp::Swap_unaligned<64, big_endian>::writeval(buf, val); |
| break; |
| default: |
| gold_unreachable(); |
| } |
| } |
| |
| // A data item in an output section. |
| |
| class Output_section_element_data : public Output_section_element |
| { |
| public: |
| Output_section_element_data(int size, bool is_signed, Expression* val) |
| : size_(size), is_signed_(is_signed), val_(val) |
| { } |
| |
| // If there is a data item, then we must create an output section. |
| bool |
| needs_output_section() const |
| { return true; } |
| |
| // Finalize symbols--we just need to update dot. |
| void |
| finalize_symbols(Symbol_table*, const Layout*, uint64_t* dot_value, |
| Output_section**) |
| { *dot_value += this->size_; } |
| |
| // Store the value in the section. |
| void |
| set_section_addresses(Symbol_table*, Layout*, Output_section*, uint64_t, |
| uint64_t* dot_value, Output_section**, std::string*, |
| Input_section_list*); |
| |
| // Print for debugging. |
| void |
| print(FILE*) const; |
| |
| private: |
| // The size in bytes. |
| int size_; |
| // Whether the value is signed. |
| bool is_signed_; |
| // The value. |
| Expression* val_; |
| }; |
| |
| // Store the value in the section. |
| |
| void |
| Output_section_element_data::set_section_addresses( |
| Symbol_table* symtab, |
| Layout* layout, |
| Output_section* os, |
| uint64_t, |
| uint64_t* dot_value, |
| Output_section** dot_section, |
| std::string*, |
| Input_section_list*) |
| { |
| gold_assert(os != NULL); |
| os->add_output_section_data(new Output_data_expression(this->size_, |
| this->is_signed_, |
| this->val_, |
| symtab, |
| layout, |
| *dot_value, |
| *dot_section)); |
| *dot_value += this->size_; |
| } |
| |
| // Print for debugging. |
| |
| void |
| Output_section_element_data::print(FILE* f) const |
| { |
| const char* s; |
| switch (this->size_) |
| { |
| case 1: |
| s = "BYTE"; |
| break; |
| case 2: |
| s = "SHORT"; |
| break; |
| case 4: |
| s = "LONG"; |
| break; |
| case 8: |
| if (this->is_signed_) |
| s = "SQUAD"; |
| else |
| s = "QUAD"; |
| break; |
| default: |
| gold_unreachable(); |
| } |
| fprintf(f, " %s(", s); |
| this->val_->print(f); |
| fprintf(f, ")\n"); |
| } |
| |
| // A fill value setting in an output section. |
| |
| class Output_section_element_fill : public Output_section_element |
| { |
| public: |
| Output_section_element_fill(Expression* val) |
| : val_(val) |
| { } |
| |
| // Update the fill value while setting section addresses. |
| void |
| set_section_addresses(Symbol_table* symtab, Layout* layout, Output_section*, |
| uint64_t, uint64_t* dot_value, |
| Output_section** dot_section, |
| std::string* fill, Input_section_list*) |
| { |
| Output_section* fill_section; |
| uint64_t fill_val = this->val_->eval_with_dot(symtab, layout, false, |
| *dot_value, *dot_section, |
| &fill_section); |
| if (fill_section != NULL) |
| gold_warning(_("fill value is not absolute")); |
| // FIXME: The GNU linker supports fill values of arbitrary length. |
| unsigned char fill_buff[4]; |
| elfcpp::Swap_unaligned<32, true>::writeval(fill_buff, fill_val); |
| fill->assign(reinterpret_cast<char*>(fill_buff), 4); |
| } |
| |
| // Print for debugging. |
| void |
| print(FILE* f) const |
| { |
| fprintf(f, " FILL("); |
| this->val_->print(f); |
| fprintf(f, ")\n"); |
| } |
| |
| private: |
| // The new fill value. |
| Expression* val_; |
| }; |
| |
| // Return whether STRING contains a wildcard character. This is used |
| // to speed up matching. |
| |
| static inline bool |
| is_wildcard_string(const std::string& s) |
| { |
| return strpbrk(s.c_str(), "?*[") != NULL; |
| } |
| |
| // An input section specification in an output section |
| |
| class Output_section_element_input : public Output_section_element |
| { |
| public: |
| Output_section_element_input(const Input_section_spec* spec, bool keep); |
| |
| // Finalize symbols--just update the value of the dot symbol. |
| void |
| finalize_symbols(Symbol_table*, const Layout*, uint64_t* dot_value, |
| Output_section** dot_section) |
| { |
| *dot_value = this->final_dot_value_; |
| *dot_section = this->final_dot_section_; |
| } |
| |
| // See whether we match FILE_NAME and SECTION_NAME as an input |
| // section. |
| bool |
| match_name(const char* file_name, const char* section_name) const; |
| |
| // Set the section address. |
| void |
| set_section_addresses(Symbol_table* symtab, Layout* layout, Output_section*, |
| uint64_t subalign, uint64_t* dot_value, |
| Output_section**, std::string* fill, |
| Input_section_list*); |
| |
| // Print for debugging. |
| void |
| print(FILE* f) const; |
| |
| private: |
| // An input section pattern. |
| struct Input_section_pattern |
| { |
| std::string pattern; |
| bool pattern_is_wildcard; |
| Sort_wildcard sort; |
| |
| Input_section_pattern(const char* patterna, size_t patternlena, |
| Sort_wildcard sorta) |
| : pattern(patterna, patternlena), |
| pattern_is_wildcard(is_wildcard_string(this->pattern)), |
| sort(sorta) |
| { } |
| }; |
| |
| typedef std::vector<Input_section_pattern> Input_section_patterns; |
| |
| // Filename_exclusions is a pair of filename pattern and a bool |
| // indicating whether the filename is a wildcard. |
| typedef std::vector<std::pair<std::string, bool> > Filename_exclusions; |
| |
| // Return whether STRING matches PATTERN, where IS_WILDCARD_PATTERN |
| // indicates whether this is a wildcard pattern. |
| static inline bool |
| match(const char* string, const char* pattern, bool is_wildcard_pattern) |
| { |
| return (is_wildcard_pattern |
| ? fnmatch(pattern, string, 0) == 0 |
| : strcmp(string, pattern) == 0); |
| } |
| |
| // See if we match a file name. |
| bool |
| match_file_name(const char* file_name) const; |
| |
| // The file name pattern. If this is the empty string, we match all |
| // files. |
| std::string filename_pattern_; |
| // Whether the file name pattern is a wildcard. |
| bool filename_is_wildcard_; |
| // How the file names should be sorted. This may only be |
| // SORT_WILDCARD_NONE or SORT_WILDCARD_BY_NAME. |
| Sort_wildcard filename_sort_; |
| // The list of file names to exclude. |
| Filename_exclusions filename_exclusions_; |
| // The list of input section patterns. |
| Input_section_patterns input_section_patterns_; |
| // Whether to keep this section when garbage collecting. |
| bool keep_; |
| // The value of dot after including all matching sections. |
| uint64_t final_dot_value_; |
| // The section where dot is defined after including all matching |
| // sections. |
| Output_section* final_dot_section_; |
| }; |
| |
| // Construct Output_section_element_input. The parser records strings |
| // as pointers into a copy of the script file, which will go away when |
| // parsing is complete. We make sure they are in std::string objects. |
| |
| Output_section_element_input::Output_section_element_input( |
| const Input_section_spec* spec, |
| bool keep) |
| : filename_pattern_(), |
| filename_is_wildcard_(false), |
| filename_sort_(spec->file.sort), |
| filename_exclusions_(), |
| input_section_patterns_(), |
| keep_(keep), |
| final_dot_value_(0), |
| final_dot_section_(NULL) |
| { |
| // The filename pattern "*" is common, and matches all files. Turn |
| // it into the empty string. |
| if (spec->file.name.length != 1 || spec->file.name.value[0] != '*') |
| this->filename_pattern_.assign(spec->file.name.value, |
| spec->file.name.length); |
| this->filename_is_wildcard_ = is_wildcard_string(this->filename_pattern_); |
| |
| if (spec->input_sections.exclude != NULL) |
| { |
| for (String_list::const_iterator p = |
| spec->input_sections.exclude->begin(); |
| p != spec->input_sections.exclude->end(); |
| ++p) |
| { |
| bool is_wildcard = is_wildcard_string(*p); |
| this->filename_exclusions_.push_back(std::make_pair(*p, |
| is_wildcard)); |
| } |
| } |
| |
| if (spec->input_sections.sections != NULL) |
| { |
| Input_section_patterns& isp(this->input_section_patterns_); |
| for (String_sort_list::const_iterator p = |
| spec->input_sections.sections->begin(); |
| p != spec->input_sections.sections->end(); |
| ++p) |
| isp.push_back(Input_section_pattern(p->name.value, p->name.length, |
| p->sort)); |
| } |
| } |
| |
| // See whether we match FILE_NAME. |
| |
| bool |
| Output_section_element_input::match_file_name(const char* file_name) const |
| { |
| if (!this->filename_pattern_.empty()) |
| { |
| // If we were called with no filename, we refuse to match a |
| // pattern which requires a file name. |
| if (file_name == NULL) |
| return false; |
| |
| if (!match(file_name, this->filename_pattern_.c_str(), |
| this->filename_is_wildcard_)) |
| return false; |
| } |
| |
| if (file_name != NULL) |
| { |
| // Now we have to see whether FILE_NAME matches one of the |
| // exclusion patterns, if any. |
| for (Filename_exclusions::const_iterator p = |
| this->filename_exclusions_.begin(); |
| p != this->filename_exclusions_.end(); |
| ++p) |
| { |
| if (match(file_name, p->first.c_str(), p->second)) |
| return false; |
| } |
| } |
| |
| return true; |
| } |
| |
| // See whether we match FILE_NAME and SECTION_NAME. |
| |
| bool |
| Output_section_element_input::match_name(const char* file_name, |
| const char* section_name) const |
| { |
| if (!this->match_file_name(file_name)) |
| return false; |
| |
| // If there are no section name patterns, then we match. |
| if (this->input_section_patterns_.empty()) |
| return true; |
| |
| // See whether we match the section name patterns. |
| for (Input_section_patterns::const_iterator p = |
| this->input_section_patterns_.begin(); |
| p != this->input_section_patterns_.end(); |
| ++p) |
| { |
| if (match(section_name, p->pattern.c_str(), p->pattern_is_wildcard)) |
| return true; |
| } |
| |
| // We didn't match any section names, so we didn't match. |
| return false; |
| } |
| |
| // Information we use to sort the input sections. |
| |
| struct Input_section_info |
| { |
| Relobj* relobj; |
| unsigned int shndx; |
| std::string section_name; |
| uint64_t size; |
| uint64_t addralign; |
| }; |
| |
| // A class to sort the input sections. |
| |
| class Input_section_sorter |
| { |
| public: |
| Input_section_sorter(Sort_wildcard filename_sort, Sort_wildcard section_sort) |
| : filename_sort_(filename_sort), section_sort_(section_sort) |
| { } |
| |
| bool |
| operator()(const Input_section_info&, const Input_section_info&) const; |
| |
| private: |
| Sort_wildcard filename_sort_; |
| Sort_wildcard section_sort_; |
| }; |
| |
| bool |
| Input_section_sorter::operator()(const Input_section_info& isi1, |
| const Input_section_info& isi2) const |
| { |
| 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)) |
| { |
| if (isi1.section_name != isi2.section_name) |
| return isi1.section_name < isi2.section_name; |
| } |
| if (this->section_sort_ == SORT_WILDCARD_BY_ALIGNMENT |
| || this->section_sort_ == SORT_WILDCARD_BY_NAME_BY_ALIGNMENT |
| || this->section_sort_ == SORT_WILDCARD_BY_ALIGNMENT_BY_NAME) |
| { |
| if (isi1.addralign != isi2.addralign) |
| return isi1.addralign < isi2.addralign; |
| } |
| if (this->filename_sort_ == SORT_WILDCARD_BY_NAME) |
| { |
| if (isi1.relobj->name() != isi2.relobj->name()) |
| return isi1.relobj->name() < isi2.relobj->name(); |
| } |
| |
| // Otherwise we leave them in the same order. |
| return false; |
| } |
| |
| // Set the section address. Look in INPUT_SECTIONS for sections which |
| // match this spec, sort them as specified, and add them to the output |
| // section. |
| |
| void |
| Output_section_element_input::set_section_addresses( |
| Symbol_table*, |
| Layout*, |
| Output_section* output_section, |
| uint64_t subalign, |
| uint64_t* dot_value, |
| Output_section** dot_section, |
| std::string* fill, |
| Input_section_list* input_sections) |
| { |
| // We build a list of sections which match each |
| // Input_section_pattern. |
| |
| typedef std::vector<std::vector<Input_section_info> > Matching_sections; |
| size_t input_pattern_count = this->input_section_patterns_.size(); |
| if (input_pattern_count == 0) |
| input_pattern_count = 1; |
| Matching_sections matching_sections(input_pattern_count); |
| |
| // Look through the list of sections for this output section. Add |
| // each one which matches to one of the elements of |
| // MATCHING_SECTIONS. |
| |
| Input_section_list::iterator p = input_sections->begin(); |
| while (p != input_sections->end()) |
| { |
| // Calling section_name and section_addralign is not very |
| // efficient. |
| Input_section_info isi; |
| isi.relobj = p->first; |
| isi.shndx = p->second; |
| |
| // Lock the object so that we can get information about the |
| // section. This is OK since we know we are single-threaded |
| // here. |
| { |
| const Task* task = reinterpret_cast<const Task*>(-1); |
| Task_lock_obj<Object> tl(task, p->first); |
| |
| isi.section_name = p->first->section_name(p->second); |
| isi.size = p->first->section_size(p->second); |
| isi.addralign = p->first->section_addralign(p->second); |
| } |
| |
| if (!this->match_file_name(isi.relobj->name().c_str())) |
| ++p; |
| else if (this->input_section_patterns_.empty()) |
| { |
| matching_sections[0].push_back(isi); |
| p = input_sections->erase(p); |
| } |
| else |
| { |
| size_t i; |
| for (i = 0; i < input_pattern_count; ++i) |
| { |
| const Input_section_pattern& |
| isp(this->input_section_patterns_[i]); |
| if (match(isi.section_name.c_str(), isp.pattern.c_str(), |
| isp.pattern_is_wildcard)) |
| break; |
| } |
| |
| if (i >= this->input_section_patterns_.size()) |
| ++p; |
| else |
| { |
| matching_sections[i].push_back(isi); |
| p = input_sections->erase(p); |
| } |
| } |
| } |
| |
| // Look through MATCHING_SECTIONS. Sort each one as specified, |
| // using a stable sort so that we get the default order when |
| // sections are otherwise equal. Add each input section to the |
| // output section. |
| |
| for (size_t i = 0; i < input_pattern_count; ++i) |
| { |
| if (matching_sections[i].empty()) |
| continue; |
| |
| gold_assert(output_section != NULL); |
| |
| const Input_section_pattern& isp(this->input_section_patterns_[i]); |
| if (isp.sort != SORT_WILDCARD_NONE |
| || this->filename_sort_ != SORT_WILDCARD_NONE) |
| std::stable_sort(matching_sections[i].begin(), |
| matching_sections[i].end(), |
| Input_section_sorter(this->filename_sort_, |
| isp.sort)); |
| |
| for (std::vector<Input_section_info>::const_iterator p = |
| matching_sections[i].begin(); |
| p != matching_sections[i].end(); |
| ++p) |
| { |
| uint64_t this_subalign = p->addralign; |
| if (this_subalign < subalign) |
| this_subalign = subalign; |
| |
| uint64_t address = align_address(*dot_value, this_subalign); |
| |
| if (address > *dot_value && !fill->empty()) |
| { |
| section_size_type length = |
| convert_to_section_size_type(address - *dot_value); |
| std::string this_fill = this->get_fill_string(fill, length); |
| Output_section_data* posd = new Output_data_const(this_fill, 0); |
| output_section->add_output_section_data(posd); |
| } |
| |
| output_section->add_input_section_for_script(p->relobj, |
| p->shndx, |
| p->size, |
| this_subalign); |
| |
| *dot_value = address + p->size; |
| } |
| } |
| |
| this->final_dot_value_ = *dot_value; |
| this->final_dot_section_ = *dot_section; |
| } |
| |
| // Print for debugging. |
| |
| void |
| Output_section_element_input::print(FILE* f) const |
| { |
| fprintf(f, " "); |
| |
| if (this->keep_) |
| fprintf(f, "KEEP("); |
| |
| if (!this->filename_pattern_.empty()) |
| { |
| bool need_close_paren = false; |
| switch (this->filename_sort_) |
| { |
| case SORT_WILDCARD_NONE: |
| break; |
| case SORT_WILDCARD_BY_NAME: |
| fprintf(f, "SORT_BY_NAME("); |
| need_close_paren = true; |
| break; |
| default: |
| gold_unreachable(); |
| } |
| |
| fprintf(f, "%s", this->filename_pattern_.c_str()); |
| |
| if (need_close_paren) |
| fprintf(f, ")"); |
| } |
| |
| if (!this->input_section_patterns_.empty() |
| || !this->filename_exclusions_.empty()) |
| { |
| fprintf(f, "("); |
| |
| bool need_space = false; |
| if (!this->filename_exclusions_.empty()) |
| { |
| fprintf(f, "EXCLUDE_FILE("); |
| bool need_comma = false; |
| for (Filename_exclusions::const_iterator p = |
| this->filename_exclusions_.begin(); |
| p != this->filename_exclusions_.end(); |
| ++p) |
| { |
| if (need_comma) |
| fprintf(f, ", "); |
| fprintf(f, "%s", p->first.c_str()); |
| need_comma = true; |
| } |
| fprintf(f, ")"); |
| need_space = true; |
| } |
| |
| for (Input_section_patterns::const_iterator p = |
| this->input_section_patterns_.begin(); |
| p != this->input_section_patterns_.end(); |
| ++p) |
| { |
| if (need_space) |
| fprintf(f, " "); |
| |
| int close_parens = 0; |
| switch (p->sort) |
| { |
| case SORT_WILDCARD_NONE: |
| break; |
| case SORT_WILDCARD_BY_NAME: |
| fprintf(f, "SORT_BY_NAME("); |
| close_parens = 1; |
| break; |
| case SORT_WILDCARD_BY_ALIGNMENT: |
| fprintf(f, "SORT_BY_ALIGNMENT("); |
| close_parens = 1; |
| break; |
| case SORT_WILDCARD_BY_NAME_BY_ALIGNMENT: |
| fprintf(f, "SORT_BY_NAME(SORT_BY_ALIGNMENT("); |
| close_parens = 2; |
| break; |
| case SORT_WILDCARD_BY_ALIGNMENT_BY_NAME: |
| fprintf(f, "SORT_BY_ALIGNMENT(SORT_BY_NAME("); |
| close_parens = 2; |
| break; |
| default: |
| gold_unreachable(); |
| } |
| |
| fprintf(f, "%s", p->pattern.c_str()); |
| |
| for (int i = 0; i < close_parens; ++i) |
| fprintf(f, ")"); |
| |
| need_space = true; |
| } |
| |
| fprintf(f, ")"); |
| } |
| |
| if (this->keep_) |
| fprintf(f, ")"); |
| |
| fprintf(f, "\n"); |
| } |
| |
| // An output section. |
| |
| class Output_section_definition : public Sections_element |
| { |
| public: |
| typedef Output_section_element::Input_section_list Input_section_list; |
| |
| Output_section_definition(const char* name, size_t namelen, |
| const Parser_output_section_header* header); |
| |
| // Finish the output section with the information in the trailer. |
| void |
| finish(const Parser_output_section_trailer* trailer); |
| |
| // Add a symbol to be defined. |
| void |
| add_symbol_assignment(const char* name, size_t length, Expression* value, |
| bool provide, bool hidden); |
| |
| // Add an assignment to the special dot symbol. |
| void |
| add_dot_assignment(Expression* value); |
| |
| // Add an assertion. |
| void |
| add_assertion(Expression* check, const char* message, size_t messagelen); |
| |
| // Add a data item to the current output section. |
| void |
| add_data(int size, bool is_signed, Expression* val); |
| |
| // Add a setting for the fill value. |
| void |
| add_fill(Expression* val); |
| |
| // Add an input section specification. |
| void |
| add_input_section(const Input_section_spec* spec, bool keep); |
| |
| // Record that the output section is relro. |
| void |
| set_is_relro() |
| { this->is_relro_ = true; } |
| |
| // Create any required output sections. |
| void |
| create_sections(Layout*); |
| |
| // Add any symbols being defined to the symbol table. |
| void |
| add_symbols_to_table(Symbol_table* symtab); |
| |
| // Finalize symbols and check assertions. |
| void |
| finalize_symbols(Symbol_table*, const Layout*, uint64_t*); |
| |
| // Return the output section name to use for an input file name and |
| // section name. |
| const char* |
| output_section_name(const char* file_name, const char* section_name, |
| Output_section***); |
| |
| // Return whether to place an orphan section after this one. |
| bool |
| place_orphan_here(const Output_section *os, bool* exact, bool*) const; |
| |
| // Set the section address. |
| void |
| set_section_addresses(Symbol_table* symtab, Layout* layout, |
| uint64_t* dot_value, uint64_t* load_address); |
| |
| // Check a constraint (ONLY_IF_RO, etc.) on an output section. If |
| // this section is constrained, and the input sections do not match, |
| // return the constraint, and set *POSD. |
| Section_constraint |
| check_constraint(Output_section_definition** posd); |
| |
| // See if this is the alternate output section for a constrained |
| // output section. If it is, transfer the Output_section and return |
| // true. Otherwise return false. |
| bool |
| alternate_constraint(Output_section_definition*, Section_constraint); |
| |
| // Get the list of segments to use for an allocated section when |
| // using a PHDRS clause. |
| Output_section* |
| allocate_to_segment(String_list** phdrs_list, bool* orphan); |
| |
| // Look for an output section by name and return the address, the |
| // load address, the alignment, and the size. This is used when an |
| // expression refers to an output section which was not actually |
| // created. This returns true if the section was found, false |
| // otherwise. |
| bool |
| get_output_section_info(const char*, uint64_t*, uint64_t*, uint64_t*, |
| uint64_t*) const; |
| |
| // Return the associated Output_section if there is one. |
| Output_section* |
| get_output_section() const |
| { return this->output_section_; } |
| |
| // Print the contents to the FILE. This is for debugging. |
| void |
| print(FILE*) const; |
| |
| private: |
| typedef std::vector<Output_section_element*> Output_section_elements; |
| |
| // The output section name. |
| std::string name_; |
| // The address. This may be NULL. |
| Expression* address_; |
| // The load address. This may be NULL. |
| Expression* load_address_; |
| // The alignment. This may be NULL. |
| Expression* align_; |
| // The input section alignment. This may be NULL. |
| Expression* subalign_; |
| // The constraint, if any. |
| Section_constraint constraint_; |
| // The fill value. This may be NULL. |
| Expression* fill_; |
| // The list of segments this section should go into. This may be |
| // NULL. |
| String_list* phdrs_; |
| // The list of elements defining the section. |
| Output_section_elements elements_; |
| // The Output_section created for this definition. This will be |
| // NULL if none was created. |
| Output_section* output_section_; |
| // The address after it has been evaluated. |
| uint64_t evaluated_address_; |
| // The load address after it has been evaluated. |
| uint64_t evaluated_load_address_; |
| // The alignment after it has been evaluated. |
| uint64_t evaluated_addralign_; |
| // The output section is relro. |
| bool is_relro_; |
| }; |
| |
| // Constructor. |
| |
| Output_section_definition::Output_section_definition( |
| const char* name, |
| size_t namelen, |
| const Parser_output_section_header* header) |
| : name_(name, namelen), |
| address_(header->address), |
| load_address_(header->load_address), |
| align_(header->align), |
| subalign_(header->subalign), |
| constraint_(header->constraint), |
| fill_(NULL), |
| phdrs_(NULL), |
| elements_(), |
| output_section_(NULL), |
| evaluated_address_(0), |
| evaluated_load_address_(0), |
| evaluated_addralign_(0), |
| is_relro_(false) |
| { |
| } |
| |
| // Finish an output section. |
| |
| void |
| Output_section_definition::finish(const Parser_output_section_trailer* trailer) |
| { |
| this->fill_ = trailer->fill; |
| this->phdrs_ = trailer->phdrs; |
| } |
| |
| // Add a symbol to be defined. |
| |
| void |
| Output_section_definition::add_symbol_assignment(const char* name, |
| size_t length, |
| Expression* value, |
| bool provide, |
| bool hidden) |
| { |
| Output_section_element* p = new Output_section_element_assignment(name, |
| length, |
| value, |
| provide, |
| hidden); |
| this->elements_.push_back(p); |
| } |
| |
| // Add an assignment to the special dot symbol. |
| |
| void |
| Output_section_definition::add_dot_assignment(Expression* value) |
| { |
| Output_section_element* p = new Output_section_element_dot_assignment(value); |
| this->elements_.push_back(p); |
| } |
| |
| // Add an assertion. |
| |
| void |
| Output_section_definition::add_assertion(Expression* check, |
| const char* message, |
| size_t messagelen) |
| { |
| Output_section_element* p = new Output_section_element_assertion(check, |
| message, |
| messagelen); |
| this->elements_.push_back(p); |
| } |
| |
| // Add a data item to the current output section. |
| |
| void |
| Output_section_definition::add_data(int size, bool is_signed, Expression* val) |
| { |
| Output_section_element* p = new Output_section_element_data(size, is_signed, |
| val); |
| this->elements_.push_back(p); |
| } |
| |
| // Add a setting for the fill value. |
| |
| void |
| Output_section_definition::add_fill(Expression* val) |
| { |
| Output_section_element* p = new Output_section_element_fill(val); |
| this->elements_.push_back(p); |
| } |
| |
| // Add an input section specification. |
| |
| void |
| Output_section_definition::add_input_section(const Input_section_spec* spec, |
| bool keep) |
| { |
| Output_section_element* p = new Output_section_element_input(spec, keep); |
| this->elements_.push_back(p); |
| } |
| |
| // Create any required output sections. We need an output section if |
| // there is a data statement here. |
| |
| void |
| Output_section_definition::create_sections(Layout* layout) |
| { |
| if (this->output_section_ != NULL) |
| return; |
| for (Output_section_elements::const_iterator p = this->elements_.begin(); |
| p != this->elements_.end(); |
| ++p) |
| { |
| if ((*p)->needs_output_section()) |
| { |
| const char* name = this->name_.c_str(); |
| this->output_section_ = layout->make_output_section_for_script(name); |
| return; |
| } |
| } |
| } |
| |
| // Add any symbols being defined to the symbol table. |
| |
| void |
| Output_section_definition::add_symbols_to_table(Symbol_table* symtab) |
| { |
| for (Output_section_elements::iterator p = this->elements_.begin(); |
| p != this->elements_.end(); |
| ++p) |
| (*p)->add_symbols_to_table(symtab); |
| } |
| |
| // Finalize symbols and check assertions. |
| |
| void |
| Output_section_definition::finalize_symbols(Symbol_table* symtab, |
| const Layout* layout, |
| uint64_t* dot_value) |
| { |
| if (this->output_section_ != NULL) |
| *dot_value = this->output_section_->address(); |
| else |
| { |
| uint64_t address = *dot_value; |
| if (this->address_ != NULL) |
| { |
| Output_section* dummy; |
| address = this->address_->eval_with_dot(symtab, layout, true, |
| *dot_value, NULL, |
| &dummy); |
| } |
| if (this->align_ != NULL) |
| { |
| Output_section* dummy; |
| uint64_t align = this->align_->eval_with_dot(symtab, layout, true, |
| *dot_value, |
| NULL, |
| &dummy); |
| address = align_address(address, align); |
| } |
| *dot_value = address; |
| } |
| |
| Output_section* dot_section = this->output_section_; |
| for (Output_section_elements::iterator p = this->elements_.begin(); |
| p != this->elements_.end(); |
| ++p) |
| (*p)->finalize_symbols(symtab, layout, dot_value, &dot_section); |
| } |
| |
| // Return the output section name to use for an input section name. |
| |
| const char* |
| Output_section_definition::output_section_name(const char* file_name, |
| const char* section_name, |
| Output_section*** slot) |
| { |
| // Ask each element whether it matches NAME. |
| for (Output_section_elements::const_iterator p = this->elements_.begin(); |
| p != this->elements_.end(); |
| ++p) |
| { |
| if ((*p)->match_name(file_name, section_name)) |
| { |
| // We found a match for NAME, which means that it should go |
| // into this output section. |
| *slot = &this->output_section_; |
| return this->name_.c_str(); |
| } |
| } |
| |
| // We don't know about this section name. |
| return NULL; |
| } |
| |
| // Return whether to place an orphan output section after this |
| // section. |
| |
| bool |
| Output_section_definition::place_orphan_here(const Output_section *os, |
| bool* exact, |
| bool* is_relro) const |
| { |
| *is_relro = this->is_relro_; |
| |
| // Check for the simple case first. |
| if (this->output_section_ != NULL |
| && this->output_section_->type() == os->type() |
| && this->output_section_->flags() == os->flags()) |
| { |
| *exact = true; |
| return true; |
| } |
| |
| // Otherwise use some heuristics. |
| |
| if ((os->flags() & elfcpp::SHF_ALLOC) == 0) |
| return false; |
| |
| if (os->type() == elfcpp::SHT_NOBITS) |
| { |
| if (this->name_ == ".bss") |
| { |
| *exact = true; |
| return true; |
| } |
| if (this->output_section_ != NULL |
| && this->output_section_->type() == elfcpp::SHT_NOBITS) |
| return true; |
| } |
| else if (os->type() == elfcpp::SHT_NOTE) |
| { |
| if (this->output_section_ != NULL |
| && this->output_section_->type() == elfcpp::SHT_NOTE) |
| { |
| *exact = true; |
| return true; |
| } |
| if (this->name_.compare(0, 5, ".note") == 0) |
| { |
| *exact = true; |
| return true; |
| } |
| if (this->name_ == ".interp") |
| return true; |
| if (this->output_section_ != NULL |
| && this->output_section_->type() == elfcpp::SHT_PROGBITS |
| && (this->output_section_->flags() & elfcpp::SHF_WRITE) == 0) |
| return true; |
| } |
| else if (os->type() == elfcpp::SHT_REL || os->type() == elfcpp::SHT_RELA) |
| { |
| if (this->name_.compare(0, 4, ".rel") == 0) |
| { |
| *exact = true; |
| return true; |
| } |
| if (this->output_section_ != NULL |
| && (this->output_section_->type() == elfcpp::SHT_REL |
| || this->output_section_->type() == elfcpp::SHT_RELA)) |
| { |
| *exact = true; |
| return true; |
| } |
| if (this->output_section_ != NULL |
| && this->output_section_->type() == elfcpp::SHT_PROGBITS |
| && (this->output_section_->flags() & elfcpp::SHF_WRITE) == 0) |
| return true; |
| } |
| else if (os->type() == elfcpp::SHT_PROGBITS |
| && (os->flags() & elfcpp::SHF_WRITE) != 0) |
| { |
| if (this->name_ == ".data") |
| { |
| *exact = true; |
| return true; |
| } |
| if (this->output_section_ != NULL |
| && this->output_section_->type() == elfcpp::SHT_PROGBITS |
| && (this->output_section_->flags() & elfcpp::SHF_WRITE) != 0) |
| return true; |
| } |
| else if (os->type() == elfcpp::SHT_PROGBITS |
| && (os->flags() & elfcpp::SHF_EXECINSTR) != 0) |
| { |
| if (this->name_ == ".text") |
| { |
| *exact = true; |
| return true; |
| } |
| if (this->output_section_ != NULL |
| && this->output_section_->type() == elfcpp::SHT_PROGBITS |
| && (this->output_section_->flags() & elfcpp::SHF_EXECINSTR) != 0) |
| return true; |
| } |
| else if (os->type() == elfcpp::SHT_PROGBITS |
| || (os->type() != elfcpp::SHT_PROGBITS |
| && (os->flags() & elfcpp::SHF_WRITE) == 0)) |
| { |
| if (this->name_ == ".rodata") |
| { |
| *exact = true; |
| return true; |
| } |
| if (this->output_section_ != NULL |
| && this->output_section_->type() == elfcpp::SHT_PROGBITS |
| && (this->output_section_->flags() & elfcpp::SHF_WRITE) == 0) |
| return true; |
| } |
| |
| return false; |
| } |
| |
| // Set the section address. Note that the OUTPUT_SECTION_ field will |
| // be NULL if no input sections were mapped to this output section. |
| // We still have to adjust dot and process symbol assignments. |
| |
| void |
| Output_section_definition::set_section_addresses(Symbol_table* symtab, |
| Layout* layout, |
| uint64_t* dot_value, |
| uint64_t* load_address) |
| { |
| uint64_t address; |
| if (this->address_ == NULL) |
| address = *dot_value; |
| else |
| { |
| Output_section* dummy; |
| address = this->address_->eval_with_dot(symtab, layout, true, |
| *dot_value, NULL, &dummy); |
| } |
| |
| uint64_t align; |
| if (this->align_ == NULL) |
| { |
| if (this->output_section_ == NULL) |
| align = 0; |
| else |
| align = this->output_section_->addralign(); |
| } |
| else |
| { |
| Output_section* align_section; |
| align = this->align_->eval_with_dot(symtab, layout, true, *dot_value, |
| NULL, &align_section); |
| if (align_section != NULL) |
| gold_warning(_("alignment of section %s is not absolute"), |
| this->name_.c_str()); |
| if (this->output_section_ != NULL) |
| this->output_section_->set_addralign(align); |
| } |
| |
| address = align_address(address, align); |
| |
| uint64_t start_address = address; |
| |
| *dot_value = address; |
| |
| // The address of non-SHF_ALLOC sections is forced to zero, |
| // regardless of what the linker script wants. |
| if (this->output_section_ != NULL |
| && (this->output_section_->flags() & elfcpp::SHF_ALLOC) != 0) |
| this->output_section_->set_address(address); |
| |
| this->evaluated_address_ = address; |
| this->evaluated_addralign_ = align; |
| |
| if (this->load_address_ == NULL) |
| this->evaluated_load_address_ = address; |
| else |
| { |
| Output_section* dummy; |
| uint64_t load_address = |
| this->load_address_->eval_with_dot(symtab, layout, true, *dot_value, |
| this->output_section_, &dummy); |
| if (this->output_section_ != NULL) |
| this->output_section_->set_load_address(load_address); |
| this->evaluated_load_address_ = load_address; |
| } |
| |
| 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); |
| if (subalign_section != NULL) |
| gold_warning(_("subalign of section %s is not absolute"), |
| this->name_.c_str()); |
| } |
| |
| std::string fill; |
| if (this->fill_ != NULL) |
| { |
| // FIXME: The GNU linker supports fill values of arbitrary |
| // length. |
| Output_section* fill_section; |
| uint64_t fill_val = this->fill_->eval_with_dot(symtab, layout, true, |
| *dot_value, |
| NULL, |
| &fill_section); |
| if (fill_section != NULL) |
| gold_warning(_("fill of section %s is not absolute"), |
| this->name_.c_str()); |
| unsigned char fill_buff[4]; |
| elfcpp::Swap_unaligned<32, true>::writeval(fill_buff, fill_val); |
| fill.assign(reinterpret_cast<char*>(fill_buff), 4); |
| } |
| |
| Input_section_list input_sections; |
| if (this->output_section_ != NULL) |
| { |
| // Get the list of input sections attached to this output |
| // section. This will leave the output section with only |
| // Output_section_data entries. |
| address += this->output_section_->get_input_sections(address, |
| fill, |
| &input_sections); |
| *dot_value = address; |
| } |
| |
| Output_section* dot_section = this->output_section_; |
| for (Output_section_elements::iterator p = this->elements_.begin(); |
| p != this->elements_.end(); |
| ++p) |
| (*p)->set_section_addresses(symtab, layout, this->output_section_, |
| subalign, dot_value, &dot_section, &fill, |
| &input_sections); |
| |
| gold_assert(input_sections.empty()); |
| |
| if (this->load_address_ == NULL || this->output_section_ == NULL) |
| *load_address = *dot_value; |
| else |
| *load_address = (this->output_section_->load_address() |
| + (*dot_value - start_address)); |
| |
| if (this->output_section_ != NULL) |
| { |
| if (this->is_relro_) |
| this->output_section_->set_is_relro(); |
| else |
| this->output_section_->clear_is_relro(); |
| } |
| } |
| |
| // Check a constraint (ONLY_IF_RO, etc.) on an output section. If |
| // this section is constrained, and the input sections do not match, |
| // return the constraint, and set *POSD. |
| |
| Section_constraint |
| Output_section_definition::check_constraint(Output_section_definition** posd) |
| { |
| switch (this->constraint_) |
| { |
| case CONSTRAINT_NONE: |
| return CONSTRAINT_NONE; |
| |
| case CONSTRAINT_ONLY_IF_RO: |
| if (this->output_section_ != NULL |
| && (this->output_section_->flags() & elfcpp::SHF_WRITE) != 0) |
| { |
| *posd = this; |
| return CONSTRAINT_ONLY_IF_RO; |
| } |
| return CONSTRAINT_NONE; |
| |
| case CONSTRAINT_ONLY_IF_RW: |
| if (this->output_section_ != NULL |
| && (this->output_section_->flags() & elfcpp::SHF_WRITE) == 0) |
| { |
| *posd = this; |
| return CONSTRAINT_ONLY_IF_RW; |
| } |
| return CONSTRAINT_NONE; |
| |
| case CONSTRAINT_SPECIAL: |
| if (this->output_section_ != NULL) |
| gold_error(_("SPECIAL constraints are not implemented")); |
| return CONSTRAINT_NONE; |
| |
| default: |
| gold_unreachable(); |
| } |
| } |
| |
| // See if this is the alternate output section for a constrained |
| // output section. If it is, transfer the Output_section and return |
| // true. Otherwise return false. |
| |
| bool |
| Output_section_definition::alternate_constraint( |
| Output_section_definition* posd, |
| Section_constraint constraint) |
| { |
| if (this->name_ != posd->name_) |
| return false; |
| |
| switch (constraint) |
| { |
| case CONSTRAINT_ONLY_IF_RO: |
| if (this->constraint_ != CONSTRAINT_ONLY_IF_RW) |
| return false; |
| break; |
| |
| case CONSTRAINT_ONLY_IF_RW: |
| if (this->constraint_ != CONSTRAINT_ONLY_IF_RO) |
| return false; |
| break; |
| |
| default: |
| gold_unreachable(); |
| } |
| |
| // We have found the alternate constraint. We just need to move |
| // over the Output_section. When constraints are used properly, |
| // THIS should not have an output_section pointer, as all the input |
| // sections should have matched the other definition. |
| |
| if (this->output_section_ != NULL) |
| gold_error(_("mismatched definition for constrained sections")); |
| |
| this->output_section_ = posd->output_section_; |
| posd->output_section_ = NULL; |
| |
| if (this->is_relro_) |
| this->output_section_->set_is_relro(); |
| else |
| this->output_section_->clear_is_relro(); |
| |
| return true; |
| } |
| |
| // Get the list of segments to use for an allocated section when using |
| // a PHDRS clause. |
| |
| Output_section* |
| Output_section_definition::allocate_to_segment(String_list** phdrs_list, |
| bool* orphan) |
| { |
| if (this->output_section_ == NULL) |
| return NULL; |
| if ((this->output_section_->flags() & elfcpp::SHF_ALLOC) == 0) |
| return NULL; |
| *orphan = false; |
| if (this->phdrs_ != NULL) |
| *phdrs_list = this->phdrs_; |
| return this->output_section_; |
| } |
| |
| // Look for an output section by name and return the address, the load |
| // address, the alignment, and the size. This is used when an |
| // expression refers to an output section which was not actually |
| // created. This returns true if the section was found, false |
| // otherwise. |
| |
| bool |
| Output_section_definition::get_output_section_info(const char* name, |
| uint64_t* address, |
| uint64_t* load_address, |
| uint64_t* addralign, |
| uint64_t* size) const |
| { |
| if (this->name_ != name) |
| return false; |
| |
| if (this->output_section_ != NULL) |
| { |
| *address = this->output_section_->address(); |
| if (this->output_section_->has_load_address()) |
| *load_address = this->output_section_->load_address(); |
| else |
| *load_address = *address; |
| *addralign = this->output_section_->addralign(); |
| *size = this->output_section_->current_data_size(); |
| } |
| else |
| { |
| *address = this->evaluated_address_; |
| *load_address = this->evaluated_load_address_; |
| *addralign = this->evaluated_addralign_; |
| *size = 0; |
| } |
| |
| return true; |
| } |
| |
| // Print for debugging. |
| |
| void |
| Output_section_definition::print(FILE* f) const |
| { |
| fprintf(f, " %s ", this->name_.c_str()); |
| |
| if (this->address_ != NULL) |
| { |
| this->address_->print(f); |
| fprintf(f, " "); |
| } |
| |
| fprintf(f, ": "); |
| |
| if (this->load_address_ != NULL) |
| { |
| fprintf(f, "AT("); |
| this->load_address_->print(f); |
| fprintf(f, ") "); |
| } |
| |
| if (this->align_ != NULL) |
| { |
| fprintf(f, "ALIGN("); |
| this->align_->print(f); |
| fprintf(f, ") "); |
| } |
| |
| if (this->subalign_ != NULL) |
| { |
| fprintf(f, "SUBALIGN("); |
| this->subalign_->print(f); |
| fprintf(f, ") "); |
| } |
| |
| fprintf(f, "{\n"); |
| |
| for (Output_section_elements::const_iterator p = this->elements_.begin(); |
| p != this->elements_.end(); |
| ++p) |
| (*p)->print(f); |
| |
| fprintf(f, " }"); |
| |
| if (this->fill_ != NULL) |
| { |
| fprintf(f, " = "); |
| this->fill_->print(f); |
| } |
| |
| if (this->phdrs_ != NULL) |
| { |
| for (String_list::const_iterator p = this->phdrs_->begin(); |
| p != this->phdrs_->end(); |
| ++p) |
| fprintf(f, " :%s", p->c_str()); |
| } |
| |
| fprintf(f, "\n"); |
| } |
| |
| // An output section created to hold orphaned input sections. These |
| // do not actually appear in linker scripts. However, for convenience |
| // when setting the output section addresses, we put a marker to these |
| // sections in the appropriate place in the list of SECTIONS elements. |
| |
| class Orphan_output_section : public Sections_element |
| { |
| public: |
| Orphan_output_section(Output_section* os) |
| : os_(os) |
| { } |
| |
| // Return whether to place an orphan section after this one. |
| bool |
| place_orphan_here(const Output_section *os, bool* exact, bool*) const; |
| |
| // Set section addresses. |
| void |
| set_section_addresses(Symbol_table*, Layout*, uint64_t*, uint64_t*); |
| |
| // Get the list of segments to use for an allocated section when |
| // using a PHDRS clause. |
| Output_section* |
| allocate_to_segment(String_list**, bool*); |
| |
| // Return the associated Output_section. |
| Output_section* |
| get_output_section() const |
| { return this->os_; } |
| |
| // Print for debugging. |
| void |
| print(FILE* f) const |
| { |
| fprintf(f, " marker for orphaned output section %s\n", |
| this->os_->name()); |
| } |
| |
| private: |
| Output_section* os_; |
| }; |
| |
| // Whether to place another orphan section after this one. |
| |
| bool |
| Orphan_output_section::place_orphan_here(const Output_section* os, |
| bool* exact, |
| bool* is_relro) const |
| { |
| if (this->os_->type() == os->type() |
| && this->os_->flags() == os->flags()) |
| { |
| *exact = true; |
| *is_relro = this->os_->is_relro(); |
| return true; |
| } |
| return false; |
| } |
| |
| // Set section addresses. |
| |
| void |
| Orphan_output_section::set_section_addresses(Symbol_table*, Layout*, |
| uint64_t* dot_value, |
| uint64_t* load_address) |
| { |
| typedef std::list<std::pair<Relobj*, unsigned int> > Input_section_list; |
| |
| bool have_load_address = *load_address != *dot_value; |
| |
| uint64_t address = *dot_value; |
| address = align_address(address, this->os_->addralign()); |
| |
| if ((this->os_->flags() & elfcpp::SHF_ALLOC) != 0) |
| { |
| this->os_->set_address(address); |
| if (have_load_address) |
| this->os_->set_load_address(align_address(*load_address, |
| this->os_->addralign())); |
| } |
| |
| Input_section_list input_sections; |
| address += this->os_->get_input_sections(address, "", &input_sections); |
| |
| for (Input_section_list::iterator p = input_sections.begin(); |
| p != input_sections.end(); |
| ++p) |
| { |
| uint64_t addralign; |
| uint64_t size; |
| |
| // We know what are single-threaded, so it is OK to lock the |
| // object. |
| { |
| const Task* task = reinterpret_cast<const Task*>(-1); |
| Task_lock_obj<Object> tl(task, p->first); |
| addralign = p->first->section_addralign(p->second); |
| size = p->first->section_size(p->second); |
| } |
| |
| address = align_address(address, addralign); |
| this->os_->add_input_section_for_script(p->first, p->second, size, |
| addralign); |
| address += size; |
| } |
| |
| if (!have_load_address) |
| *load_address = address; |
| else |
| *load_address += address - *dot_value; |
| |
| *dot_value = address; |
| } |
| |
| // Get the list of segments to use for an allocated section when using |
| // a PHDRS clause. If this is an allocated section, return the |
| // Output_section. We don't change the list of segments. |
| |
| Output_section* |
| Orphan_output_section::allocate_to_segment(String_list**, bool* orphan) |
| { |
| if ((this->os_->flags() & elfcpp::SHF_ALLOC) == 0) |
| return NULL; |
| *orphan = true; |
| return this->os_; |
| } |
| |
| // Class Phdrs_element. A program header from a PHDRS clause. |
| |
| class Phdrs_element |
| { |
| public: |
| Phdrs_element(const char* name, size_t namelen, unsigned int type, |
| bool includes_filehdr, bool includes_phdrs, |
| bool is_flags_valid, unsigned int flags, |
| Expression* load_address) |
| : name_(name, namelen), type_(type), includes_filehdr_(includes_filehdr), |
| includes_phdrs_(includes_phdrs), is_flags_valid_(is_flags_valid), |
| flags_(flags), load_address_(load_address), load_address_value_(0), |
| segment_(NULL) |
| { } |
| |
| // Return the name of this segment. |
| const std::string& |
| name() const |
| { return this->name_; } |
| |
| // Return the type of the segment. |
| unsigned int |
| type() const |
| { return this->type_; } |
| |
| // Whether to include the file header. |
| bool |
| includes_filehdr() const |
| { return this->includes_filehdr_; } |
| |
| // Whether to include the program headers. |
| bool |
| includes_phdrs() const |
| { return this->includes_phdrs_; } |
| |
| // Return whether there is a load address. |
| bool |
| has_load_address() const |
| { return this->load_address_ != NULL; } |
| |
| // Evaluate the load address expression if there is one. |
| void |
| eval_load_address(Symbol_table* symtab, Layout* layout) |
| { |
| if (this->load_address_ != NULL) |
| this->load_address_value_ = this->load_address_->eval(symtab, layout, |
| true); |
| } |
| |
| // Return the load address. |
| uint64_t |
| load_address() const |
| { |
| gold_assert(this->load_address_ != NULL); |
| return this->load_address_value_; |
| } |
| |
| // Create the segment. |
| Output_segment* |
| create_segment(Layout* layout) |
| { |
| this->segment_ = layout->make_output_segment(this->type_, this->flags_); |
| return this->segment_; |
| } |
| |
| // Return the segment. |
| Output_segment* |
| segment() |
| { return this->segment_; } |
| |
| // Set the segment flags if appropriate. |
| void |
| set_flags_if_valid() |
| { |
| if (this->is_flags_valid_) |
| this->segment_->set_flags(this->flags_); |
| } |
| |
| // Print for debugging. |
| void |
| print(FILE*) const; |
| |
| private: |
| // The name used in the script. |
| std::string name_; |
| // The type of the segment (PT_LOAD, etc.). |
| unsigned int type_; |
| // Whether this segment includes the file header. |
| bool includes_filehdr_; |
| // Whether this segment includes the section headers. |
| bool includes_phdrs_; |
| // Whether the flags were explicitly specified. |
| bool is_flags_valid_; |
| // The flags for this segment (PF_R, etc.) if specified. |
| unsigned int flags_; |
| // The expression for the load address for this segment. This may |
| // be NULL. |
| Expression* load_address_; |
| // The actual load address from evaluating the expression. |
| uint64_t load_address_value_; |
| // The segment itself. |
| Output_segment* segment_; |
| }; |
| |
| // Print for debugging. |
| |
| void |
| Phdrs_element::print(FILE* f) const |
| { |
| fprintf(f, " %s 0x%x", this->name_.c_str(), this->type_); |
| if (this->includes_filehdr_) |
| fprintf(f, " FILEHDR"); |
| if (this->includes_phdrs_) |
| fprintf(f, " PHDRS"); |
| if (this->is_flags_valid_) |
| fprintf(f, " FLAGS(%u)", this->flags_); |
| if (this->load_address_ != NULL) |
| { |
| fprintf(f, " AT("); |
| this->load_address_->print(f); |
| fprintf(f, ")"); |
| } |
| fprintf(f, ";\n"); |
| } |
| |
| // Class Script_sections. |
| |
| Script_sections::Script_sections() |
| : saw_sections_clause_(false), |
| in_sections_clause_(false), |
| sections_elements_(NULL), |
| output_section_(NULL), |
| phdrs_elements_(NULL), |
| data_segment_align_index_(-1U), |
| saw_relro_end_(false) |
| { |
| } |
| |
| // Start a SECTIONS clause. |
| |
| void |
| Script_sections::start_sections() |
| { |
| gold_assert(!this->in_sections_clause_ && this->output_section_ == NULL); |
| this->saw_sections_clause_ = true; |
| this->in_sections_clause_ = true; |
| if (this->sections_elements_ == NULL) |
| this->sections_elements_ = new Sections_elements; |
| } |
| |
| // Finish a SECTIONS clause. |
| |
| void |
| Script_sections::finish_sections() |
| { |
| gold_assert(this->in_sections_clause_ && this->output_section_ == NULL); |
| this->in_sections_clause_ = false; |
| } |
| |
| // Add a symbol to be defined. |
| |
| void |
| Script_sections::add_symbol_assignment(const char* name, size_t length, |
| Expression* val, bool provide, |
| bool hidden) |
| { |
| if (this->output_section_ != NULL) |
| this->output_section_->add_symbol_assignment(name, length, val, |
| provide, hidden); |
| else |
| { |
| Sections_element* p = new Sections_element_assignment(name, length, |
| val, provide, |
| hidden); |
| this->sections_elements_->push_back(p); |
| } |
| } |
| |
| // Add an assignment to the special dot symbol. |
| |
| void |
| Script_sections::add_dot_assignment(Expression* val) |
| { |
| if (this->output_section_ != NULL) |
| this->output_section_->add_dot_assignment(val); |
| else |
| { |
| Sections_element* p = new Sections_element_dot_assignment(val); |
| this->sections_elements_->push_back(p); |
| } |
| } |
| |
| // Add an assertion. |
| |
| void |
| Script_sections::add_assertion(Expression* check, const char* message, |
| size_t messagelen) |
| { |
| if (this->output_section_ != NULL) |
| this->output_section_->add_assertion(check, message, messagelen); |
| else |
| { |
| Sections_element* p = new Sections_element_assertion(check, message, |
| messagelen); |
| this->sections_elements_->push_back(p); |
| } |
| } |
| |
| // Start processing entries for an output section. |
| |
| void |
| Script_sections::start_output_section( |
| const char* name, |
| size_t namelen, |
| const Parser_output_section_header *header) |
| { |
| Output_section_definition* posd = new Output_section_definition(name, |
| namelen, |
| header); |
| this->sections_elements_->push_back(posd); |
| gold_assert(this->output_section_ == NULL); |
| this->output_section_ = posd; |
| } |
| |
| // Stop processing entries for an output section. |
| |
| void |
| Script_sections::finish_output_section( |
| const Parser_output_section_trailer* trailer) |
| { |
| gold_assert(this->output_section_ != NULL); |
| this->output_section_->finish(trailer); |
| this->output_section_ = NULL; |
| } |
| |
| // Add a data item to the current output section. |
| |
| void |
| Script_sections::add_data(int size, bool is_signed, Expression* val) |
| { |
| gold_assert(this->output_section_ != NULL); |
| this->output_section_->add_data(size, is_signed, val); |
| } |
| |
| // Add a fill value setting to the current output section. |
| |
| void |
| Script_sections::add_fill(Expression* val) |
| { |
| gold_assert(this->output_section_ != NULL); |
| this->output_section_->add_fill(val); |
| } |
| |
| // Add an input section specification to the current output section. |
| |
| void |
| Script_sections::add_input_section(const Input_section_spec* spec, bool keep) |
| { |
| gold_assert(this->output_section_ != NULL); |
| this->output_section_->add_input_section(spec, keep); |
| } |
| |
| // This is called when we see DATA_SEGMENT_ALIGN. It means that any |
| // subsequent output sections may be relro. |
| |
| void |
| Script_sections::data_segment_align() |
| { |
| if (this->data_segment_align_index_ != -1U) |
| gold_error(_("DATA_SEGMENT_ALIGN may only appear once in a linker script")); |
| this->data_segment_align_index_ = this->sections_elements_->size(); |
| } |
| |
| // This is called when we see DATA_SEGMENT_RELRO_END. It means that |
| // any output sections seen since DATA_SEGMENT_ALIGN are relro. |
| |
| void |
| Script_sections::data_segment_relro_end() |
| { |
| if (this->saw_relro_end_) |
| gold_error(_("DATA_SEGMENT_RELRO_END may only appear once " |
| "in a linker script")); |
| this->saw_relro_end_ = true; |
| |
| if (this->data_segment_align_index_ == -1U) |
| gold_error(_("DATA_SEGMENT_RELRO_END must follow DATA_SEGMENT_ALIGN")); |
| else |
| { |
| for (size_t i = this->data_segment_align_index_; |
| i < this->sections_elements_->size(); |
| ++i) |
| (*this->sections_elements_)[i]->set_is_relro(); |
| } |
| } |
| |
| // Create any required sections. |
| |
| void |
| Script_sections::create_sections(Layout* layout) |
| { |
| if (!this->saw_sections_clause_) |
| return; |
| for (Sections_elements::iterator p = this->sections_elements_->begin(); |
| p != this->sections_elements_->end(); |
| ++p) |
| (*p)->create_sections(layout); |
| } |
| |
| // Add any symbols we are defining to the symbol table. |
| |
| void |
| Script_sections::add_symbols_to_table(Symbol_table* symtab) |
| { |
| if (!this->saw_sections_clause_) |
| return; |
| for (Sections_elements::iterator p = this->sections_elements_->begin(); |
| p != this->sections_elements_->end(); |
| ++p) |
| (*p)->add_symbols_to_table(symtab); |
| } |
| |
| // Finalize symbols and check assertions. |
| |
| void |
| Script_sections::finalize_symbols(Symbol_table* symtab, const Layout* layout) |
| { |
| if (!this->saw_sections_clause_) |
| return; |
| uint64_t dot_value = 0; |
| for (Sections_elements::iterator p = this->sections_elements_->begin(); |
| p != this->sections_elements_->end(); |
| ++p) |
| (*p)->finalize_symbols(symtab, layout, &dot_value); |
| } |
| |
| // Return the name of the output section to use for an input file name |
| // and section name. |
| |
| const char* |
| Script_sections::output_section_name(const char* file_name, |
| const char* section_name, |
| Output_section*** output_section_slot) |
| { |
| for (Sections_elements::const_iterator p = this->sections_elements_->begin(); |
| p != this->sections_elements_->end(); |
| ++p) |
| { |
| const char* ret = (*p)->output_section_name(file_name, section_name, |
| output_section_slot); |
| |
| if (ret != NULL) |
| { |
| // The special name /DISCARD/ means that the input section |
| // should be discarded. |
| if (strcmp(ret, "/DISCARD/") == 0) |
| { |
| *output_section_slot = NULL; |
| return NULL; |
| } |
| return ret; |
| } |
| } |
| |
| // If we couldn't find a mapping for the name, the output section |
| // gets the name of the input section. |
| |
| *output_section_slot = NULL; |
| |
| return section_name; |
| } |
| |
| // Place a marker for an orphan output section into the SECTIONS |
| // clause. |
| |
| void |
| Script_sections::place_orphan(Output_section* os) |
| { |
| // Look for an output section definition which matches the output |
| // section. Put a marker after that section. |
| bool is_relro = false; |
| Sections_elements::iterator place = this->sections_elements_->end(); |
| for (Sections_elements::iterator p = this->sections_elements_->begin(); |
| p != this->sections_elements_->end(); |
| ++p) |
| { |
| bool exact = false; |
| bool is_relro_here; |
| if ((*p)->place_orphan_here(os, &exact, &is_relro_here)) |
| { |
| place = p; |
| is_relro = is_relro_here; |
| if (exact) |
| break; |
| } |
| } |
| |
| // The insert function puts the new element before the iterator. |
| if (place != this->sections_elements_->end()) |
| ++place; |
| |
| this->sections_elements_->insert(place, new Orphan_output_section(os)); |
| |
| if (is_relro) |
| os->set_is_relro(); |
| else |
| os->clear_is_relro(); |
| } |
| |
| // Set the addresses of all the output sections. Walk through all the |
| // elements, tracking the dot symbol. Apply assignments which set |
| // absolute symbol values, in case they are used when setting dot. |
| // Fill in data statement values. As we find output sections, set the |
| // address, set the address of all associated input sections, and |
| // update dot. Return the segment which should hold the file header |
| // and segment headers, if any. |
| |
| 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(); |
| p != this->sections_elements_->end(); |
| ++p) |
| { |
| Output_section_definition* posd; |
| Section_constraint failed_constraint = (*p)->check_constraint(&posd); |
| if (failed_constraint != CONSTRAINT_NONE) |
| { |
| Sections_elements::iterator q; |
| for (q = this->sections_elements_->begin(); |
| q != this->sections_elements_->end(); |
| ++q) |
| { |
| if (q != p) |
| { |
| if ((*q)->alternate_constraint(posd, failed_constraint)) |
| break; |
| } |
| } |
| |
| if (q == this->sections_elements_->end()) |
| gold_error(_("no matching section constraint")); |
| } |
| } |
| |
| // Force the alignment of the first TLS section to be the maximum |
| // alignment of all TLS sections. |
| Output_section* first_tls = NULL; |
| uint64_t tls_align = 0; |
| for (Sections_elements::const_iterator p = this->sections_elements_->begin(); |
| p != this->sections_elements_->end(); |
| ++p) |
| { |
| Output_section *os = (*p)->get_output_section(); |
| if (os != NULL && (os->flags() & elfcpp::SHF_TLS) != 0) |
| { |
| if (first_tls == NULL) |
| first_tls = os; |
| if (os->addralign() > tls_align) |
| tls_align = os->addralign(); |
| } |
| } |
| if (first_tls != NULL) |
| first_tls->set_addralign(tls_align); |
| |
| // For a relocatable link, we implicitly set dot to zero. |
| uint64_t dot_value = 0; |
| uint64_t load_address = 0; |
| for (Sections_elements::iterator p = this->sections_elements_->begin(); |
| p != this->sections_elements_->end(); |
| ++p) |
| (*p)->set_section_addresses(symtab, layout, &dot_value, &load_address); |
| |
| if (this->phdrs_elements_ != NULL) |
| { |
| for (Phdrs_elements::iterator p = this->phdrs_elements_->begin(); |
| p != this->phdrs_elements_->end(); |
| ++p) |
| (*p)->eval_load_address(symtab, layout); |
| } |
| |
| return this->create_segments(layout); |
| } |
| |
| // Sort the sections in order to put them into segments. |
| |
| class Sort_output_sections |
| { |
| public: |
| bool |
| operator()(const Output_section* os1, const Output_section* os2) const; |
| }; |
| |
| bool |
| Sort_output_sections::operator()(const Output_section* os1, |
| const Output_section* os2) const |
| { |
| // Sort first by the load address. |
| uint64_t lma1 = (os1->has_load_address() |
| ? os1->load_address() |
| : os1->address()); |
| uint64_t lma2 = (os2->has_load_address() |
| ? os2->load_address() |
| : os2->address()); |
| if (lma1 != lma2) |
| return lma1 < lma2; |
| |
| // Then sort by the virtual address. |
| if (os1->address() != os2->address()) |
| return os1->address() < os2->address(); |
| |
| // Sort TLS sections to the end. |
| bool tls1 = (os1->flags() & elfcpp::SHF_TLS) != 0; |
| bool tls2 = (os2->flags() & elfcpp::SHF_TLS) != 0; |
| if (tls1 != tls2) |
| return tls2; |
| |
| // Sort PROGBITS before NOBITS. |
| if (os1->type() == elfcpp::SHT_PROGBITS && os2->type() == elfcpp::SHT_NOBITS) |
| return true; |
| if (os1->type() == elfcpp::SHT_NOBITS && os2->type() == elfcpp::SHT_PROGBITS) |
| return false; |
| |
| // Otherwise we don't care. |
| return false; |
| } |
| |
| // Return whether OS is a BSS section. This is a SHT_NOBITS section. |
| // We treat a section with the SHF_TLS flag set as taking up space |
| // even if it is SHT_NOBITS (this is true of .tbss), as we allocate |
| // space for them in the file. |
| |
| bool |
| Script_sections::is_bss_section(const Output_section* os) |
| { |
| return (os->type() == elfcpp::SHT_NOBITS |
| && (os->flags() & elfcpp::SHF_TLS) == 0); |
| } |
| |
| // Return the size taken by the file header and the program headers. |
| |
| size_t |
| Script_sections::total_header_size(Layout* layout) const |
| { |
| size_t segment_count = layout->segment_count(); |
| size_t file_header_size; |
| size_t segment_headers_size; |
| if (parameters->target().get_size() == 32) |
| { |
| file_header_size = elfcpp::Elf_sizes<32>::ehdr_size; |
| segment_headers_size = segment_count * elfcpp::Elf_sizes<32>::phdr_size; |
| } |
| else if (parameters->target().get_size() == 64) |
| { |
| file_header_size = elfcpp::Elf_sizes<64>::ehdr_size; |
| segment_headers_size = segment_count * elfcpp::Elf_sizes<64>::phdr_size; |
| } |
| else |
| gold_unreachable(); |
| |
| return file_header_size + segment_headers_size; |
| } |
| |
| // Return the amount we have to subtract from the LMA to accomodate |
| // headers of the given size. The complication is that the file |
| // header have to be at the start of a page, as otherwise it will not |
| // be at the start of the file. |
| |
| uint64_t |
| Script_sections::header_size_adjustment(uint64_t lma, |
| size_t sizeof_headers) const |
| { |
| const uint64_t abi_pagesize = parameters->target().abi_pagesize(); |
| uint64_t hdr_lma = lma - sizeof_headers; |
| hdr_lma &= ~(abi_pagesize - 1); |
| return lma - hdr_lma; |
| } |
| |
| // Create the PT_LOAD segments when using a SECTIONS clause. Returns |
| // the segment which should hold the file header and segment headers, |
| // if any. |
| |
| Output_segment* |
| Script_sections::create_segments(Layout* layout) |
| { |
| gold_assert(this->saw_sections_clause_); |
| |
| if (parameters->options().relocatable()) |
| return NULL; |
| |
| if (this->saw_phdrs_clause()) |
| return create_segments_from_phdrs_clause(layout); |
| |
| Layout::Section_list sections; |
| layout->get_allocated_sections(§ions); |
| |
| // Sort the sections by address. |
| std::stable_sort(sections.begin(), sections.end(), Sort_output_sections()); |
| |
| this->create_note_and_tls_segments(layout, §ions); |
| |
| // Walk through the sections adding them to PT_LOAD segments. |
| const uint64_t abi_pagesize = parameters->target().abi_pagesize(); |
| 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; |
| for (Layout::Section_list::iterator p = sections.begin(); |
| p != sections.end(); |
| ++p) |
| { |
| const uint64_t vma = (*p)->address(); |
| const uint64_t lma = ((*p)->has_load_address() |
| ? (*p)->load_address() |
| : vma); |
| const uint64_t size = (*p)->current_data_size(); |
| |
| bool need_new_segment; |
| if (current_seg == NULL) |
| need_new_segment = true; |
| else if (lma - vma != last_lma - last_vma) |
| { |
| // This section has a different LMA relationship than the |
| // last one; we need a new segment. |
| need_new_segment = true; |
| } |
| else if (align_address(last_lma + last_size, abi_pagesize) |
| < align_address(lma, abi_pagesize)) |
| { |
| // Putting this section in the segment would require |
| // skipping a page. |
| need_new_segment = true; |
| } |
| else if (is_bss_section(*plast) && !is_bss_section(*p)) |
| { |
| // A non-BSS section can not follow a BSS section in the |
| // same segment. |
| need_new_segment = true; |
| } |
| else if (is_current_seg_readonly |
| && ((*p)->flags() & elfcpp::SHF_WRITE) != 0 |
| && !parameters->options().omagic()) |
| { |
| // Don't put a writable section in the same segment as a |
| // non-writable section. |
| need_new_segment = true; |
| } |
| else |
| { |
| // Otherwise, reuse the existing segment. |
| need_new_segment = false; |
| } |
| |
| elfcpp::Elf_Word seg_flags = |
| Layout::section_flags_to_segment((*p)->flags()); |
| |
| if (need_new_segment) |
| { |
| current_seg = layout->make_output_segment(elfcpp::PT_LOAD, |
| seg_flags); |
| current_seg->set_addresses(vma, lma); |
| if (first_seg == NULL) |
| first_seg = current_seg; |
| is_current_seg_readonly = true; |
| } |
| |
| current_seg->add_output_section(*p, seg_flags); |
| |
| if (((*p)->flags() & elfcpp::SHF_WRITE) != 0) |
| is_current_seg_readonly = false; |
| |
| plast = p; |
| last_vma = vma; |
| last_lma = lma; |
| last_size = size; |
| } |
| |
| // An ELF program should work even if the program headers are not in |
| // a PT_LOAD segment. However, it appears that the Linux kernel |
| // does not set the AT_PHDR auxiliary entry in that case. It sets |
| // the load address to p_vaddr - p_offset of the first PT_LOAD |
| // segment. It then sets AT_PHDR to the load address plus the |
| // offset to the program headers, e_phoff in the file header. This |
| // fails when the program headers appear in the file before the |
| // first PT_LOAD segment. Therefore, we always create a PT_LOAD |
| // segment to hold the file header and the program headers. This is |
| // effectively what the GNU linker does, and it is slightly more |
| // efficient in any case. We try to use the first PT_LOAD segment |
| // if we can, otherwise we make a new one. |
| |
| if (first_seg == NULL) |
| return NULL; |
| |
| size_t sizeof_headers = this->total_header_size(layout); |
| |
| uint64_t vma = first_seg->vaddr(); |
| uint64_t lma = first_seg->paddr(); |
| |
| uint64_t subtract = this->header_size_adjustment(lma, sizeof_headers); |
| |
| if ((lma & (abi_pagesize - 1)) >= sizeof_headers) |
| { |
| first_seg->set_addresses(vma - subtract, lma - subtract); |
| return first_seg; |
| } |
| |
| // If there is no room to squeeze in the headers, then punt. The |
| // resulting executable probably won't run on GNU/Linux, but we |
| // trust that the user knows what they are doing. |
| if (lma < subtract || vma < subtract) |
| return NULL; |
| |
| Output_segment* load_seg = layout->make_output_segment(elfcpp::PT_LOAD, |
| elfcpp::PF_R); |
| load_seg->set_addresses(vma - subtract, lma - subtract); |
| |
| return load_seg; |
| } |
| |
| // Create a PT_NOTE segment for each SHT_NOTE section and a PT_TLS |
| // segment if there are any SHT_TLS sections. |
| |
| void |
| Script_sections::create_note_and_tls_segments( |
| Layout* layout, |
| const Layout::Section_list* sections) |
| { |
| gold_assert(!this->saw_phdrs_clause()); |
| |
| bool saw_tls = false; |
| for (Layout::Section_list::const_iterator p = sections->begin(); |
| p != sections->end(); |
| ++p) |
| { |
| if ((*p)->type() == elfcpp::SHT_NOTE) |
| { |
| elfcpp::Elf_Word seg_flags = |
| Layout::section_flags_to_segment((*p)->flags()); |
| Output_segment* oseg = layout->make_output_segment(elfcpp::PT_NOTE, |
| seg_flags); |
| oseg->add_output_section(*p, seg_flags); |
| |
| // Incorporate any subsequent SHT_NOTE sections, in the |
| // hopes that the script is sensible. |
| Layout::Section_list::const_iterator pnext = p + 1; |
| while (pnext != sections->end() |
| && (*pnext)->type() == elfcpp::SHT_NOTE) |
| { |
| seg_flags = Layout::section_flags_to_segment((*pnext)->flags()); |
| oseg->add_output_section(*pnext, seg_flags); |
| p = pnext; |
| ++pnext; |
| } |
| } |
| |
| if (((*p)->flags() & elfcpp::SHF_TLS) != 0) |
| { |
| if (saw_tls) |
| gold_error(_("TLS sections are not adjacent")); |
| |
| elfcpp::Elf_Word seg_flags = |
| Layout::section_flags_to_segment((*p)->flags()); |
| Output_segment* oseg = layout->make_output_segment(elfcpp::PT_TLS, |
| seg_flags); |
| oseg->add_output_section(*p, seg_flags); |
| |
| Layout::Section_list::const_iterator pnext = p + 1; |
| while (pnext != sections->end() |
| && ((*pnext)->flags() & elfcpp::SHF_TLS) != 0) |
| { |
| seg_flags = Layout::section_flags_to_segment((*pnext)->flags()); |
| oseg->add_output_section(*pnext, seg_flags); |
| p = pnext; |
| ++pnext; |
| } |
| |
| saw_tls = true; |
| } |
| } |
| } |
| |
| // Add a program header. The PHDRS clause is syntactically distinct |
| // from the SECTIONS clause, but we implement it with the SECTIONS |
| // support becauase PHDRS is useless if there is no SECTIONS clause. |
| |
| void |
| Script_sections::add_phdr(const char* name, size_t namelen, unsigned int type, |
| bool includes_filehdr, bool includes_phdrs, |
| bool is_flags_valid, unsigned int flags, |
| Expression* load_address) |
| { |
| if (this->phdrs_elements_ == NULL) |
| this->phdrs_elements_ = new Phdrs_elements(); |
| this->phdrs_elements_->push_back(new Phdrs_element(name, namelen, type, |
| includes_filehdr, |
| includes_phdrs, |
| is_flags_valid, flags, |
| load_address)); |
| } |
| |
| // Return the number of segments we expect to create based on the |
| // SECTIONS clause. This is used to implement SIZEOF_HEADERS. |
| |
| size_t |
| Script_sections::expected_segment_count(const Layout* layout) const |
| { |
| if (this->saw_phdrs_clause()) |
| return this->phdrs_elements_->size(); |
| |
| Layout::Section_list sections; |
| layout->get_allocated_sections(§ions); |
| |
| // We assume that we will need two PT_LOAD segments. |
| size_t ret = 2; |
| |
| bool saw_note = false; |
| bool saw_tls = false; |
| for (Layout::Section_list::const_iterator p = sections.begin(); |
| p != sections.end(); |
| ++p) |
| { |
| if ((*p)->type() == elfcpp::SHT_NOTE) |
| { |
| // Assume that all note sections will fit into a single |
| // PT_NOTE segment. |
| if (!saw_note) |
| { |
| ++ret; |
| saw_note = true; |
| } |
| } |
| else if (((*p)->flags() & elfcpp::SHF_TLS) != 0) |
| { |
| // There can only be one PT_TLS segment. |
| if (!saw_tls) |
| { |
| ++ret; |
| saw_tls = true; |
| } |
| } |
| } |
| |
| return ret; |
| } |
| |
| // Create the segments from a PHDRS clause. Return the segment which |
| // should hold the file header and program headers, if any. |
| |
| Output_segment* |
| Script_sections::create_segments_from_phdrs_clause(Layout* layout) |
| { |
| this->attach_sections_using_phdrs_clause(layout); |
| return this->set_phdrs_clause_addresses(layout); |
| } |
| |
| // Create the segments from the PHDRS clause, and put the output |
| // sections in them. |
| |
| void |
| Script_sections::attach_sections_using_phdrs_clause(Layout* layout) |
| { |
| typedef std::map<std::string, Output_segment*> Name_to_segment; |
| Name_to_segment name_to_segment; |
| for (Phdrs_elements::const_iterator p = this->phdrs_elements_->begin(); |
| p != this->phdrs_elements_->end(); |
| ++p) |
| name_to_segment[(*p)->name()] = (*p)->create_segment(layout); |
| |
| // Walk through the output sections and attach them to segments. |
| // 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; |
| for (Sections_elements::const_iterator p = this->sections_elements_->begin(); |
| p != this->sections_elements_->end(); |
| ++p) |
| { |
| bool orphan; |
| Output_section* os = (*p)->allocate_to_segment(&phdr_names, &orphan); |
| if (os == NULL) |
| continue; |
| |
| if (phdr_names == NULL) |
| { |
| gold_error(_("allocated section not in any segment")); |
| continue; |
| } |
| |
| // 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 |
| // PT_INTERP segment will pick up following orphan sections, |
| // which does not make sense. If this is not an orphan section, |
| // we trust the linker script. |
| if (orphan) |
| { |
| String_list::iterator q = phdr_names->begin(); |
| while (q != phdr_names->end()) |
| { |
| Name_to_segment::const_iterator r = name_to_segment.find(*q); |
| // We give errors about unknown segments below. |
| if (r == name_to_segment.end() |
| || r->second->type() == elfcpp::PT_LOAD) |
| ++q; |
| else |
| q = phdr_names->erase(q); |
| } |
| } |
| |
| bool in_load_segment = false; |
| for (String_list::const_iterator q = phdr_names->begin(); |
| q != phdr_names->end(); |
| ++q) |
| { |
| Name_to_segment::const_iterator r = name_to_segment.find(*q); |
| if (r == name_to_segment.end()) |
| gold_error(_("no segment %s"), q->c_str()); |
| else |
| { |
| elfcpp::Elf_Word seg_flags = |
| Layout::section_flags_to_segment(os->flags()); |
| r->second->add_output_section(os, seg_flags); |
| |
| if (r->second->type() == elfcpp::PT_LOAD) |
| { |
| if (in_load_segment) |
| gold_error(_("section in two PT_LOAD segments")); |
| in_load_segment = true; |
| } |
| } |
| } |
| |
| if (!in_load_segment) |
| gold_error(_("allocated section not in any PT_LOAD segment")); |
| } |
| } |
| |
| // Set the addresses for segments created from a PHDRS clause. Return |
| // the segment which should hold the file header and program headers, |
| // if any. |
| |
| Output_segment* |
| Script_sections::set_phdrs_clause_addresses(Layout* layout) |
| { |
| Output_segment* load_seg = NULL; |
| for (Phdrs_elements::const_iterator p = this->phdrs_elements_->begin(); |
| p != this->phdrs_elements_->end(); |
| ++p) |
| { |
| // Note that we have to set the flags after adding the output |
| // sections to the segment, as adding an output segment can |
| // change the flags. |
| (*p)->set_flags_if_valid(); |
| |
| Output_segment* oseg = (*p)->segment(); |
| |
| if (oseg->type() != elfcpp::PT_LOAD) |
| { |
| // The addresses of non-PT_LOAD segments are set from the |
| // PT_LOAD segments. |
| if ((*p)->has_load_address()) |
| gold_error(_("may only specify load address for PT_LOAD segment")); |
| continue; |
| } |
| |
| // The output sections should have addresses from the SECTIONS |
| // clause. The addresses don't have to be in order, so find the |
| // one with the lowest load address. Use that to set the |
| // address of the segment. |
| |
| Output_section* osec = oseg->section_with_lowest_load_address(); |
| if (osec == NULL) |
| { |
| oseg->set_addresses(0, 0); |
| continue; |
| } |
| |
| uint64_t vma = osec->address(); |
| uint64_t lma = osec->has_load_address() ? osec->load_address() : vma; |
| |
| // Override the load address of the section with the load |
| // address specified for the segment. |
| if ((*p)->has_load_address()) |
| { |
| if (osec->has_load_address()) |
| gold_warning(_("PHDRS load address overrides " |
| "section %s load address"), |
| osec->name()); |
| |
| lma = (*p)->load_address(); |
| } |
| |
| bool headers = (*p)->includes_filehdr() && (*p)->includes_phdrs(); |
| if (!headers && ((*p)->includes_filehdr() || (*p)->includes_phdrs())) |
| { |
| // We could support this if we wanted to. |
| gold_error(_("using only one of FILEHDR and PHDRS is " |
| "not currently supported")); |
| } |
| if (headers) |
| { |
| size_t sizeof_headers = this->total_header_size(layout); |
| uint64_t subtract = this->header_size_adjustment(lma, |
| sizeof_headers); |
| if (lma >= subtract && vma >= subtract) |
| { |
| lma -= subtract; |
| vma -= subtract; |
| } |
| else |
| { |
| gold_error(_("sections loaded on first page without room " |
| "for file and program headers " |
| "are not supported")); |
| } |
| |
| if (load_seg != NULL) |
| gold_error(_("using FILEHDR and PHDRS on more than one " |
| "PT_LOAD segment is not currently supported")); |
| load_seg = oseg; |
| } |
| |
| oseg->set_addresses(vma, lma); |
| } |
| |
| return load_seg; |
| } |
| |
| // Add the file header and segment headers to non-load segments |
| // specified in the PHDRS clause. |
| |
| void |
| Script_sections::put_headers_in_phdrs(Output_data* file_header, |
| Output_data* segment_headers) |
| { |
| gold_assert(this->saw_phdrs_clause()); |
| for (Phdrs_elements::iterator p = this->phdrs_elements_->begin(); |
| p != this->phdrs_elements_->end(); |
| ++p) |
| { |
| if ((*p)->type() != elfcpp::PT_LOAD) |
| { |
| if ((*p)->includes_phdrs()) |
| (*p)->segment()->add_initial_output_data(segment_headers); |
| if ((*p)->includes_filehdr()) |
| (*p)->segment()->add_initial_output_data(file_header); |
| } |
| } |
| } |
| |
| // Look for an output section by name and return the address, the load |
| // address, the alignment, and the size. This is used when an |
| // expression refers to an output section which was not actually |
| // created. This returns true if the section was found, false |
| // otherwise. |
| |
| bool |
| Script_sections::get_output_section_info(const char* name, uint64_t* address, |
| uint64_t* load_address, |
| uint64_t* addralign, |
| uint64_t* size) const |
| { |
| if (!this->saw_sections_clause_) |
| return false; |
| for (Sections_elements::const_iterator p = this->sections_elements_->begin(); |
| p != this->sections_elements_->end(); |
| ++p) |
| if ((*p)->get_output_section_info(name, address, load_address, addralign, |
| size)) |
| return true; |
| return false; |
| } |
| |
| // Print the SECTIONS clause to F for debugging. |
| |
| void |
| Script_sections::print(FILE* f) const |
| { |
| if (!this->saw_sections_clause_) |
| return; |
| |
| fprintf(f, "SECTIONS {\n"); |
| |
| for (Sections_elements::const_iterator p = this->sections_elements_->begin(); |
| p != this->sections_elements_->end(); |
| ++p) |
| (*p)->print(f); |
| |
| fprintf(f, "}\n"); |
| |
| if (this->phdrs_elements_ != NULL) |
| { |
| fprintf(f, "PHDRS {\n"); |
| for (Phdrs_elements::const_iterator p = this->phdrs_elements_->begin(); |
| p != this->phdrs_elements_->end(); |
| ++p) |
| (*p)->print(f); |
| fprintf(f, "}\n"); |
| } |
| } |
| |
| } // End namespace gold. |