X-Git-Url: http://drtracing.org/?a=blobdiff_plain;f=gold%2Foutput.h;h=7ed53ff06d7717bd437a91462c1ce9c543dfe5d8;hb=c55fe0967e9ec38c1e9d9d3ffc4db30a49323302;hp=943474b42e0f4fe7f25247fad7e02511d71cb5ce;hpb=a2fb1b05e4af3fac54faac6c07a4717f2cb34aae;p=deliverable%2Fbinutils-gdb.git diff --git a/gold/output.h b/gold/output.h index 943474b42e..7ed53ff06d 100644 --- a/gold/output.h +++ b/gold/output.h @@ -4,90 +4,1162 @@ #define GOLD_OUTPUT_H #include +#include #include "elfcpp.h" +#include "layout.h" +#include "reloc-types.h" namespace gold { +class General_options; class Object; +class Symbol; class Output_file; +class Output_section; +class Target; +template +class Sized_target; +template +class Sized_relobj; -// An abtract class for data which has to go into the output file -// which is not associated with any input section. +// An abtract class for data which has to go into the output file. class Output_data { public: - Output_data(off_t size = 0) - : size_(size) + explicit Output_data(off_t data_size = 0) + : address_(0), data_size_(data_size), offset_(-1) { } virtual ~Output_data(); - // Return the size of the data. + // Return the address. This is only valid after Layout::finalize is + // finished. + uint64_t + address() const + { return this->address_; } + + // Return the size of the data. This must be valid after + // Layout::finalize calls set_address, but need not be valid before + // then. off_t - size() - { return this->size_; } + data_size() const + { return this->data_size_; } - // Write the data to the output file at the specified offset. This - // must be implemented by the real class. - virtual void - write(Output_file*, off_t off) = 0; + // Return the file offset. This is only valid after + // Layout::finalize is finished. + off_t + offset() const + { return this->offset_; } + + // Return the required alignment. + uint64_t + addralign() const + { return this->do_addralign(); } + + // Return whether this is an Output_section. + bool + is_section() const + { return this->do_is_section(); } + + // Return whether this is an Output_section of the specified type. + bool + is_section_type(elfcpp::Elf_Word stt) const + { return this->do_is_section_type(stt); } + + // Return whether this is an Output_section with the specified flag + // set. + bool + is_section_flag_set(elfcpp::Elf_Xword shf) const + { return this->do_is_section_flag_set(shf); } + + // Return the output section index, if there is an output section. + unsigned int + out_shndx() const + { return this->do_out_shndx(); } + + // Set the output section index, if this is an output section. + void + set_out_shndx(unsigned int shndx) + { this->do_set_out_shndx(shndx); } + + // Set the address and file offset of this data. This is called + // during Layout::finalize. + void + set_address(uint64_t addr, off_t off); + + // Write the data to the output file. This is called after + // Layout::finalize is complete. + void + write(Output_file* file) + { this->do_write(file); } + + // This is called by Layout::finalize to note that all sizes must + // now be fixed. + static void + layout_complete() + { Output_data::sizes_are_fixed = true; } protected: + // Functions that child classes may or in some cases must implement. + + // Write the data to the output file. + virtual void + do_write(Output_file*) = 0; + + // Return the required alignment. + virtual uint64_t + do_addralign() const = 0; + + // Return whether this is an Output_section. + virtual bool + do_is_section() const + { return false; } + + // Return whether this is an Output_section of the specified type. + // This only needs to be implement by Output_section. + virtual bool + do_is_section_type(elfcpp::Elf_Word) const + { return false; } + + // Return whether this is an Output_section with the specific flag + // set. This only needs to be implemented by Output_section. + virtual bool + do_is_section_flag_set(elfcpp::Elf_Xword) const + { return false; } + + // Return the output section index, if there is an output section. + virtual unsigned int + do_out_shndx() const + { gold_unreachable(); } + + // Set the output section index, if this is an output section. + virtual void + do_set_out_shndx(unsigned int) + { gold_unreachable(); } + + // Set the address and file offset of the data. This only needs to + // be implemented if the child needs to know. The child class can + // set its size in this call. + virtual void + do_set_address(uint64_t, off_t) + { } + + // Functions that child classes may call. + // Set the size of the data. void - set_size(off_t size) - { this->size_ = size; } + set_data_size(off_t data_size) + { + gold_assert(!Output_data::sizes_are_fixed); + this->data_size_ = data_size; + } + + // Return default alignment for a size--32 or 64. + static uint64_t + default_alignment(int size); private: Output_data(const Output_data&); Output_data& operator=(const Output_data&); + // This is used for verification, to make sure that we don't try to + // change any sizes after we set the section addresses. + static bool sizes_are_fixed; + + // Memory address in file (not always meaningful). + uint64_t address_; // Size of data in file. - off_t size_; + off_t data_size_; + // Offset within file. + off_t offset_; +}; + +// Output the section headers. + +class Output_section_headers : public Output_data +{ + public: + Output_section_headers(int size, + bool big_endian, + const Layout*, + const Layout::Segment_list*, + const Layout::Section_list*, + const Stringpool*); + + // Write the data to the file. + void + do_write(Output_file*); + + // Return the required alignment. + uint64_t + do_addralign() const + { return Output_data::default_alignment(this->size_); } + + private: + // Write the data to the file with the right size and endianness. + template + void + do_sized_write(Output_file*); + + int size_; + bool big_endian_; + const Layout* layout_; + const Layout::Segment_list* segment_list_; + const Layout::Section_list* unattached_section_list_; + const Stringpool* secnamepool_; +}; + +// Output the segment headers. + +class Output_segment_headers : public Output_data +{ + public: + Output_segment_headers(int size, bool big_endian, + const Layout::Segment_list& segment_list); + + // Write the data to the file. + void + do_write(Output_file*); + + // Return the required alignment. + uint64_t + do_addralign() const + { return Output_data::default_alignment(this->size_); } + + private: + // Write the data to the file with the right size and endianness. + template + void + do_sized_write(Output_file*); + + int size_; + bool big_endian_; + const Layout::Segment_list& segment_list_; +}; + +// Output the ELF file header. + +class Output_file_header : public Output_data +{ + public: + Output_file_header(int size, + bool big_endian, + const General_options&, + const Target*, + const Symbol_table*, + const Output_segment_headers*); + + // Add information about the section headers. We lay out the ELF + // file header before we create the section headers. + void set_section_info(const Output_section_headers*, + const Output_section* shstrtab); + + // Write the data to the file. + void + do_write(Output_file*); + + // Return the required alignment. + uint64_t + do_addralign() const + { return Output_data::default_alignment(this->size_); } + + // Set the address and offset--we only implement this for error + // checking. + void + do_set_address(uint64_t, off_t off) const + { gold_assert(off == 0); } + + private: + // Write the data to the file with the right size and endianness. + template + void + do_sized_write(Output_file*); + + int size_; + bool big_endian_; + const General_options& options_; + const Target* target_; + const Symbol_table* symtab_; + const Output_segment_headers* segment_header_; + const Output_section_headers* section_header_; + const Output_section* shstrtab_; }; -// A simple cass of Output_data in which we have constant data to +// Output sections are mainly comprised of input sections. However, +// there are cases where we have data to write out which is not in an +// input section. Output_section_data is used in such cases. This is +// an abstract base class. + +class Output_section_data : public Output_data +{ + public: + Output_section_data(off_t data_size, uint64_t addralign) + : Output_data(data_size), output_section_(NULL), addralign_(addralign) + { } + + Output_section_data(uint64_t addralign) + : Output_data(0), output_section_(NULL), addralign_(addralign) + { } + + // Return the output section. + const Output_section* + output_section() const + { return this->output_section_; } + + // Record the output section. + void + set_output_section(Output_section* os); + + // Add an input section, for SHF_MERGE sections. This returns true + // if the section was handled. + bool + add_input_section(Relobj* object, unsigned int shndx) + { return this->do_add_input_section(object, shndx); } + + // Given an input OBJECT, an input section index SHNDX within that + // object, and an OFFSET relative to the start of that input + // section, return whether or not the output address is known. + // OUTPUT_SECTION_ADDRESS is the address of the output section which + // this is a part of. If this function returns true, it sets + // *POUTPUT to the output address. + virtual bool + output_address(const Relobj* object, unsigned int shndx, off_t offset, + uint64_t output_section_address, uint64_t *poutput) const + { + return this->do_output_address(object, shndx, offset, + output_section_address, poutput); + } + + protected: + // The child class must implement do_write. + + // The child class may implement specific adjustments to the output + // section. + virtual void + do_adjust_output_section(Output_section*) + { } + + // May be implemented by child class. Return true if the section + // was handled. + virtual bool + do_add_input_section(Relobj*, unsigned int) + { gold_unreachable(); } + + // The child class may implement output_address. + virtual bool + do_output_address(const Relobj*, unsigned int, off_t, uint64_t, + uint64_t*) const + { return false; } + + // Return the required alignment. + uint64_t + do_addralign() const + { return this->addralign_; } + + // Return the section index of the output section. + unsigned int + do_out_shndx() const; + + // Set the alignment. + void + set_addralign(uint64_t addralign) + { this->addralign_ = addralign; } + + private: + // The output section for this section. + const Output_section* output_section_; + // The required alignment. + uint64_t addralign_; +}; + +// A simple case of Output_data in which we have constant data to // output. -class Output_data_const : public Output_data +class Output_data_const : public Output_section_data { public: - Output_data_const(const std::string& data) - : Output_data(data.size()), data_(data) + Output_data_const(const std::string& data, uint64_t addralign) + : Output_section_data(data.size(), addralign), data_(data) { } - Output_data_const(const char* p, off_t len) - : Output_data(len), data_(p, len) + Output_data_const(const char* p, off_t len, uint64_t addralign) + : Output_section_data(len, addralign), data_(p, len) { } + Output_data_const(const unsigned char* p, off_t len, uint64_t addralign) + : Output_section_data(len, addralign), + data_(reinterpret_cast(p), len) + { } + + // Add more data. + void + add_data(const std::string& add) + { + this->data_.append(add); + this->set_data_size(this->data_.size()); + } + + // Write the data to the output file. void - write(Output_file* output, off_t off); + do_write(Output_file*); private: std::string data_; }; +// Another version of Output_data with constant data, in which the +// buffer is allocated by the caller. + +class Output_data_const_buffer : public Output_section_data +{ + public: + Output_data_const_buffer(const unsigned char* p, off_t len, + uint64_t addralign) + : Output_section_data(len, addralign), p_(p) + { } + + // Write the data the output file. + void + do_write(Output_file*); + + private: + const unsigned char* p_; +}; + +// A place holder for data written out via some other mechanism. + +class Output_data_space : public Output_section_data +{ + public: + Output_data_space(off_t data_size, uint64_t addralign) + : Output_section_data(data_size, addralign) + { } + + explicit Output_data_space(uint64_t addralign) + : Output_section_data(addralign) + { } + + // Set the size. + void + set_space_size(off_t space_size) + { this->set_data_size(space_size); } + + // Set the alignment. + void + set_space_alignment(uint64_t align) + { this->set_addralign(align); } + + // Write out the data--this must be handled elsewhere. + void + do_write(Output_file*) + { } +}; + +// A string table which goes into an output section. + +class Output_data_strtab : public Output_section_data +{ + public: + Output_data_strtab(Stringpool* strtab) + : Output_section_data(1), strtab_(strtab) + { } + + // This is called to set the address and file offset. Here we make + // sure that the Stringpool is finalized. + void + do_set_address(uint64_t, off_t); + + // Write out the data. + void + do_write(Output_file*); + + private: + Stringpool* strtab_; +}; + +// This POD class is used to represent a single reloc in the output +// file. This could be a private class within Output_data_reloc, but +// the templatization is complex enough that I broke it out into a +// separate class. The class is templatized on either elfcpp::SHT_REL +// or elfcpp::SHT_RELA, and also on whether this is a dynamic +// relocation or an ordinary relocation. + +// A relocation can be against a global symbol, a local symbol, an +// output section, or the undefined symbol at index 0. We represent +// the latter by using a NULL global symbol. + +template +class Output_reloc; + +template +class Output_reloc +{ + public: + typedef typename elfcpp::Elf_types::Elf_Addr Address; + + // An uninitialized entry. We need this because we want to put + // instances of this class into an STL container. + Output_reloc() + : local_sym_index_(INVALID_CODE) + { } + + // A reloc against a global symbol. + + Output_reloc(Symbol* gsym, unsigned int type, Output_data* od, + Address address) + : address_(address), local_sym_index_(GSYM_CODE), type_(type), + shndx_(INVALID_CODE) + { + this->u1_.gsym = gsym; + this->u2_.od = od; + } + + Output_reloc(Symbol* gsym, unsigned int type, Relobj* relobj, + unsigned int shndx, Address address) + : address_(address), local_sym_index_(GSYM_CODE), type_(type), + shndx_(shndx) + { + gold_assert(shndx != INVALID_CODE); + this->u1_.gsym = gsym; + this->u2_.relobj = relobj; + } + + // A reloc against a local symbol. + + Output_reloc(Sized_relobj* relobj, + unsigned int local_sym_index, + unsigned int type, + Output_data* od, + Address address) + : address_(address), local_sym_index_(local_sym_index), type_(type), + shndx_(INVALID_CODE) + { + gold_assert(local_sym_index != GSYM_CODE + && local_sym_index != INVALID_CODE); + this->u1_.relobj = relobj; + this->u2_.od = od; + } + + Output_reloc(Sized_relobj* relobj, + unsigned int local_sym_index, + unsigned int type, + unsigned int shndx, + Address address) + : address_(address), local_sym_index_(local_sym_index), type_(type), + shndx_(shndx) + { + gold_assert(local_sym_index != GSYM_CODE + && local_sym_index != INVALID_CODE); + gold_assert(shndx != INVALID_CODE); + this->u1_.relobj = relobj; + this->u2_.relobj = relobj; + } + + // A reloc against the STT_SECTION symbol of an output section. + + Output_reloc(Output_section* os, unsigned int type, Output_data* od, + Address address) + : address_(address), local_sym_index_(SECTION_CODE), type_(type), + shndx_(INVALID_CODE) + { + this->u1_.os = os; + this->u2_.od = od; + } + + Output_reloc(Output_section* os, unsigned int type, Relobj* relobj, + unsigned int shndx, Address address) + : address_(address), local_sym_index_(SECTION_CODE), type_(type), + shndx_(shndx) + { + gold_assert(shndx != INVALID_CODE); + this->u1_.os = os; + this->u2_.relobj = relobj; + } + + // Write the reloc entry to an output view. + void + write(unsigned char* pov) const; + + // Write the offset and info fields to Write_rel. + template + void write_rel(Write_rel*) const; + + private: + // Return the symbol index. We can't do a double template + // specialization, so we do a secondary template here. + unsigned int + get_symbol_index() const; + + // Codes for local_sym_index_. + enum + { + // Global symbol. + GSYM_CODE = -1U, + // Output section. + SECTION_CODE = -2U, + // Invalid uninitialized entry. + INVALID_CODE = -3U + }; + + union + { + // For a local symbol, the object. We will never generate a + // relocation against a local symbol in a dynamic object; that + // doesn't make sense. And our callers will always be + // templatized, so we use Sized_relobj here. + Sized_relobj* relobj; + // For a global symbol, the symbol. If this is NULL, it indicates + // a relocation against the undefined 0 symbol. + Symbol* gsym; + // For a relocation against an output section, the output section. + Output_section* os; + } u1_; + union + { + // If shndx_ is not INVALID CODE, the object which holds the input + // section being used to specify the reloc address. + Relobj* relobj; + // If shndx_ is INVALID_CODE, the output data being used to + // specify the reloc address. This may be NULL if the reloc + // address is absolute. + Output_data* od; + } u2_; + // The address offset within the input section or the Output_data. + Address address_; + // For a local symbol, the local symbol index. This is GSYM_CODE + // for a global symbol, or INVALID_CODE for an uninitialized value. + unsigned int local_sym_index_; + // The reloc type--a processor specific code. + unsigned int type_; + // If the reloc address is an input section in an object, the + // section index. This is INVALID_CODE if the reloc address is + // specified in some other way. + unsigned int shndx_; +}; + +// The SHT_RELA version of Output_reloc<>. This is just derived from +// the SHT_REL version of Output_reloc, but it adds an addend. + +template +class Output_reloc +{ + public: + typedef typename elfcpp::Elf_types::Elf_Addr Address; + typedef typename elfcpp::Elf_types::Elf_Addr Addend; + + // An uninitialized entry. + Output_reloc() + : rel_() + { } + + // A reloc against a global symbol. + + Output_reloc(Symbol* gsym, unsigned int type, Output_data* od, + Address address, Addend addend) + : rel_(gsym, type, od, address), addend_(addend) + { } + + Output_reloc(Symbol* gsym, unsigned int type, Relobj* relobj, + unsigned int shndx, Address address, Addend addend) + : rel_(gsym, type, relobj, shndx, address), addend_(addend) + { } + + // A reloc against a local symbol. + + Output_reloc(Sized_relobj* relobj, + unsigned int local_sym_index, + unsigned int type, Output_data* od, Address address, + Addend addend) + : rel_(relobj, local_sym_index, type, od, address), addend_(addend) + { } + + Output_reloc(Sized_relobj* relobj, + unsigned int local_sym_index, + unsigned int type, + unsigned int shndx, + Address address, + Addend addend) + : rel_(relobj, local_sym_index, type, shndx, address), + addend_(addend) + { } + + // A reloc against the STT_SECTION symbol of an output section. + + Output_reloc(Output_section* os, unsigned int type, Output_data* od, + Address address, Addend addend) + : rel_(os, type, od, address), addend_(addend) + { } + + Output_reloc(Output_section* os, unsigned int type, Relobj* relobj, + unsigned int shndx, Address address, Addend addend) + : rel_(os, type, relobj, shndx, address), addend_(addend) + { } + + // Write the reloc entry to an output view. + void + write(unsigned char* pov) const; + + private: + // The basic reloc. + Output_reloc rel_; + // The addend. + Addend addend_; +}; + +// Output_data_reloc is used to manage a section containing relocs. +// SH_TYPE is either elfcpp::SHT_REL or elfcpp::SHT_RELA. DYNAMIC +// indicates whether this is a dynamic relocation or a normal +// relocation. Output_data_reloc_base is a base class. +// Output_data_reloc is the real class, which we specialize based on +// the reloc type. + +template +class Output_data_reloc_base : public Output_section_data +{ + public: + typedef Output_reloc Output_reloc_type; + typedef typename Output_reloc_type::Address Address; + static const int reloc_size = + Reloc_types::reloc_size; + + // Construct the section. + Output_data_reloc_base() + : Output_section_data(Output_data::default_alignment(size)) + { } + + // Write out the data. + void + do_write(Output_file*); + + protected: + // Set the entry size and the link. + void + do_adjust_output_section(Output_section *os); + + // Add a relocation entry. + void + add(const Output_reloc_type& reloc) + { + this->relocs_.push_back(reloc); + this->set_data_size(this->relocs_.size() * reloc_size); + } + + private: + typedef std::vector Relocs; + + Relocs relocs_; +}; + +// The class which callers actually create. + +template +class Output_data_reloc; + +// The SHT_REL version of Output_data_reloc. + +template +class Output_data_reloc + : public Output_data_reloc_base +{ + private: + typedef Output_data_reloc_base Base; + + public: + typedef typename Base::Output_reloc_type Output_reloc_type; + typedef typename Output_reloc_type::Address Address; + + Output_data_reloc() + : Output_data_reloc_base() + { } + + // Add a reloc against a global symbol. + + void + add_global(Symbol* gsym, unsigned int type, Output_data* od, Address address) + { this->add(Output_reloc_type(gsym, type, od, address)); } + + void + add_global(Symbol* gsym, unsigned int type, Relobj* relobj, + unsigned int shndx, Address address) + { this->add(Output_reloc_type(gsym, type, relobj, shndx, address)); } + + // Add a reloc against a local symbol. + + void + add_local(Sized_relobj* relobj, + unsigned int local_sym_index, unsigned int type, + Output_data* od, Address address) + { this->add(Output_reloc_type(relobj, local_sym_index, type, od, address)); } + + void + add_local(Sized_relobj* relobj, + unsigned int local_sym_index, unsigned int type, + unsigned int shndx, Address address) + { this->add(Output_reloc_type(relobj, local_sym_index, type, shndx, + address)); } + + + // A reloc against the STT_SECTION symbol of an output section. + + void + add_output_section(Output_section* os, unsigned int type, + Output_data* od, Address address) + { this->add(Output_reloc_type(os, type, od, address)); } + + void + add_output_section(Output_section* os, unsigned int type, + Relobj* relobj, unsigned int shndx, Address address) + { this->add(Output_reloc_type(os, type, relobj, shndx, address)); } +}; + +// The SHT_RELA version of Output_data_reloc. + +template +class Output_data_reloc + : public Output_data_reloc_base +{ + private: + typedef Output_data_reloc_base Base; + + public: + typedef typename Base::Output_reloc_type Output_reloc_type; + typedef typename Output_reloc_type::Address Address; + typedef typename Output_reloc_type::Addend Addend; + + Output_data_reloc() + : Output_data_reloc_base() + { } + + // Add a reloc against a global symbol. + + void + add_global(Symbol* gsym, unsigned int type, Output_data* od, + Address address, Addend addend) + { this->add(Output_reloc_type(gsym, type, od, address, addend)); } + + void + add_global(Symbol* gsym, unsigned int type, Relobj* relobj, + unsigned int shndx, Address address, Addend addend) + { this->add(Output_reloc_type(gsym, type, relobj, shndx, address, addend)); } + + // Add a reloc against a local symbol. + + void + add_local(Sized_relobj* relobj, + unsigned int local_sym_index, unsigned int type, + Output_data* od, Address address, Addend addend) + { + this->add(Output_reloc_type(relobj, local_sym_index, type, od, address, + addend)); + } + + void + add_local(Sized_relobj* relobj, + unsigned int local_sym_index, unsigned int type, + unsigned int shndx, Address address, Addend addend) + { + this->add(Output_reloc_type(relobj, local_sym_index, type, shndx, address, + addend)); + } + + // A reloc against the STT_SECTION symbol of an output section. + + void + add_output_section(Output_section* os, unsigned int type, Output_data* od, + Address address, Addend addend) + { this->add(Output_reloc_type(os, type, od, address, addend)); } + + void + add_output_section(Output_section* os, unsigned int type, Relobj* relobj, + unsigned int shndx, Address address, Addend addend) + { this->add(Output_reloc_type(os, type, relobj, shndx, address, addend)); } +}; + +// Output_data_got is used to manage a GOT. Each entry in the GOT is +// for one symbol--either a global symbol or a local symbol in an +// object. The target specific code adds entries to the GOT as +// needed. + +template +class Output_data_got : public Output_section_data +{ + public: + typedef typename elfcpp::Elf_types::Elf_Addr Valtype; + + Output_data_got(const General_options* options) + : Output_section_data(Output_data::default_alignment(size)), + options_(options), entries_() + { } + + // Add an entry for a global symbol to the GOT. Return true if this + // is a new GOT entry, false if the symbol was already in the GOT. + bool + add_global(Symbol* gsym); + + // Add an entry for a local symbol to the GOT. This returns the + // offset of the new entry from the start of the GOT. + unsigned int + add_local(Object* object, unsigned int sym_index) + { + this->entries_.push_back(Got_entry(object, sym_index)); + this->set_got_size(); + return this->last_got_offset(); + } + + // Add a constant to the GOT. This returns the offset of the new + // entry from the start of the GOT. + unsigned int + add_constant(Valtype constant) + { + this->entries_.push_back(Got_entry(constant)); + this->set_got_size(); + return this->last_got_offset(); + } + + // Write out the GOT table. + void + do_write(Output_file*); + + private: + // This POD class holds a single GOT entry. + class Got_entry + { + public: + // Create a zero entry. + Got_entry() + : local_sym_index_(CONSTANT_CODE) + { this->u_.constant = 0; } + + // Create a global symbol entry. + explicit Got_entry(Symbol* gsym) + : local_sym_index_(GSYM_CODE) + { this->u_.gsym = gsym; } + + // Create a local symbol entry. + Got_entry(Object* object, unsigned int local_sym_index) + : local_sym_index_(local_sym_index) + { + gold_assert(local_sym_index != GSYM_CODE + && local_sym_index != CONSTANT_CODE); + this->u_.object = object; + } + + // Create a constant entry. The constant is a host value--it will + // be swapped, if necessary, when it is written out. + explicit Got_entry(Valtype constant) + : local_sym_index_(CONSTANT_CODE) + { this->u_.constant = constant; } + + // Write the GOT entry to an output view. + void + write(const General_options*, unsigned char* pov) const; + + private: + enum + { + GSYM_CODE = -1U, + CONSTANT_CODE = -2U + }; + + union + { + // For a local symbol, the object. + Object* object; + // For a global symbol, the symbol. + Symbol* gsym; + // For a constant, the constant. + Valtype constant; + } u_; + // For a local symbol, the local symbol index. This is GSYM_CODE + // for a global symbol, or CONSTANT_CODE for a constant. + unsigned int local_sym_index_; + }; + + typedef std::vector Got_entries; + + // Return the offset into the GOT of GOT entry I. + unsigned int + got_offset(unsigned int i) const + { return i * (size / 8); } + + // Return the offset into the GOT of the last entry added. + unsigned int + last_got_offset() const + { return this->got_offset(this->entries_.size() - 1); } + + // Set the size of the section. + void + set_got_size() + { this->set_data_size(this->got_offset(this->entries_.size())); } + + // Options. + const General_options* options_; + // The list of GOT entries. + Got_entries entries_; +}; + +// Output_data_dynamic is used to hold the data in SHT_DYNAMIC +// section. + +class Output_data_dynamic : public Output_section_data +{ + public: + Output_data_dynamic(const Target* target, Stringpool* pool) + : Output_section_data(Output_data::default_alignment(target->get_size())), + target_(target), entries_(), pool_(pool) + { } + + // Add a new dynamic entry with a fixed numeric value. + void + add_constant(elfcpp::DT tag, unsigned int val) + { this->add_entry(Dynamic_entry(tag, val)); } + + // Add a new dynamic entry with the address of output data. + void + add_section_address(elfcpp::DT tag, const Output_data* od) + { this->add_entry(Dynamic_entry(tag, od, false)); } + + // Add a new dynamic entry with the size of output data. + void + add_section_size(elfcpp::DT tag, const Output_data* od) + { this->add_entry(Dynamic_entry(tag, od, true)); } + + // Add a new dynamic entry with the address of a symbol. + void + add_symbol(elfcpp::DT tag, const Symbol* sym) + { this->add_entry(Dynamic_entry(tag, sym)); } + + // Add a new dynamic entry with a string. + void + add_string(elfcpp::DT tag, const char* str) + { this->add_entry(Dynamic_entry(tag, this->pool_->add(str, NULL))); } + + // Set the final data size. + void + do_set_address(uint64_t, off_t); + + // Write out the dynamic entries. + void + do_write(Output_file*); + + protected: + // Adjust the output section to set the entry size. + void + do_adjust_output_section(Output_section*); + + private: + // This POD class holds a single dynamic entry. + class Dynamic_entry + { + public: + // Create an entry with a fixed numeric value. + Dynamic_entry(elfcpp::DT tag, unsigned int val) + : tag_(tag), classification_(DYNAMIC_NUMBER) + { this->u_.val = val; } + + // Create an entry with the size or address of a section. + Dynamic_entry(elfcpp::DT tag, const Output_data* od, bool section_size) + : tag_(tag), + classification_(section_size + ? DYNAMIC_SECTION_SIZE + : DYNAMIC_SECTION_ADDRESS) + { this->u_.od = od; } + + // Create an entry with the address of a symbol. + Dynamic_entry(elfcpp::DT tag, const Symbol* sym) + : tag_(tag), classification_(DYNAMIC_SYMBOL) + { this->u_.sym = sym; } + + // Create an entry with a string. + Dynamic_entry(elfcpp::DT tag, const char* str) + : tag_(tag), classification_(DYNAMIC_STRING) + { this->u_.str = str; } + + // Write the dynamic entry to an output view. + template + void + write(unsigned char* pov, const Stringpool* ACCEPT_SIZE_ENDIAN) const; + + private: + enum Classification + { + // Number. + DYNAMIC_NUMBER, + // Section address. + DYNAMIC_SECTION_ADDRESS, + // Section size. + DYNAMIC_SECTION_SIZE, + // Symbol adress. + DYNAMIC_SYMBOL, + // String. + DYNAMIC_STRING + }; + + union + { + // For DYNAMIC_NUMBER. + unsigned int val; + // For DYNAMIC_SECTION_ADDRESS and DYNAMIC_SECTION_SIZE. + const Output_data* od; + // For DYNAMIC_SYMBOL. + const Symbol* sym; + // For DYNAMIC_STRING. + const char* str; + } u_; + // The dynamic tag. + elfcpp::DT tag_; + // The type of entry. + Classification classification_; + }; + + // Add an entry to the list. + void + add_entry(const Dynamic_entry& entry) + { this->entries_.push_back(entry); } + + // Sized version of write function. + template + void + sized_write(Output_file* of); + + // The type of the list of entries. + typedef std::vector Dynamic_entries; + + // The target. + const Target* target_; + // The entries. + Dynamic_entries entries_; + // The pool used for strings. + Stringpool* pool_; +}; + // An output section. We don't expect to have too many output // sections, so we don't bother to do a template on the size. -class Output_section +class Output_section : public Output_data { public: // Create an output section, giving the name, type, and flags. Output_section(const char* name, elfcpp::Elf_Word, elfcpp::Elf_Xword); - ~Output_section(); + virtual ~Output_section(); - // Add a new input section named NAME with header SHDR from object - // OBJECT. Return the offset within the output section. + // Add a new input section SHNDX, named NAME, with header SHDR, from + // object OBJECT. Return the offset within the output section. template off_t - add_input_section(Object* object, const char *name, + add_input_section(Relobj* object, unsigned int shndx, const char *name, const elfcpp::Shdr& shdr); + // Add generated data POSD to this output section. + void + add_output_section_data(Output_section_data* posd); + // Return the section name. const char* name() const @@ -103,29 +1175,431 @@ class Output_section flags() const { return this->flags_; } + // Return the section index in the output file. + unsigned int + do_out_shndx() const + { return this->out_shndx_; } + + // Set the output section index. + void + do_set_out_shndx(unsigned int shndx) + { this->out_shndx_ = shndx; } + + // Return the entsize field. + uint64_t + entsize() const + { return this->entsize_; } + + // Set the entsize field. + void + set_entsize(uint64_t v); + + // Set the link field to the output section index of a section. + void + set_link_section(const Output_data* od) + { + gold_assert(this->link_ == 0 + && !this->should_link_to_symtab_ + && !this->should_link_to_dynsym_); + this->link_section_ = od; + } + + // Set the link field to a constant. + void + set_link(unsigned int v) + { + gold_assert(this->link_section_ == NULL + && !this->should_link_to_symtab_ + && !this->should_link_to_dynsym_); + this->link_ = v; + } + + // Record that this section should link to the normal symbol table. + void + set_should_link_to_symtab() + { + gold_assert(this->link_section_ == NULL + && this->link_ == 0 + && !this->should_link_to_dynsym_); + this->should_link_to_symtab_ = true; + } + + // Record that this section should link to the dynamic symbol table. + void + set_should_link_to_dynsym() + { + gold_assert(this->link_section_ == NULL + && this->link_ == 0 + && !this->should_link_to_symtab_); + this->should_link_to_dynsym_ = true; + } + + // Return the info field. + unsigned int + info() const + { + gold_assert(this->info_section_ == NULL); + return this->info_; + } + + // Set the info field to the output section index of a section. + void + set_info_section(const Output_data* od) + { + gold_assert(this->info_ == 0); + this->info_section_ = od; + } + + // Set the info field to a constant. + void + set_info(unsigned int v) + { + gold_assert(this->info_section_ == NULL); + this->info_ = v; + } + + // Set the addralign field. + void + set_addralign(uint64_t v) + { this->addralign_ = v; } + + // Indicate that we need a symtab index. + void + set_needs_symtab_index() + { this->needs_symtab_index_ = true; } + + // Return whether we need a symtab index. + bool + needs_symtab_index() const + { return this->needs_symtab_index_; } + + // Get the symtab index. + unsigned int + symtab_index() const + { + gold_assert(this->symtab_index_ != 0); + return this->symtab_index_; + } + + // Set the symtab index. + void + set_symtab_index(unsigned int index) + { + gold_assert(index != 0); + this->symtab_index_ = index; + } + + // Indicate that we need a dynsym index. + void + set_needs_dynsym_index() + { this->needs_dynsym_index_ = true; } + + // Return whether we need a dynsym index. + bool + needs_dynsym_index() const + { return this->needs_dynsym_index_; } + + // Get the dynsym index. + unsigned int + dynsym_index() const + { + gold_assert(this->dynsym_index_ != 0); + return this->dynsym_index_; + } + + // Set the dynsym index. + void + set_dynsym_index(unsigned int index) + { + gold_assert(index != 0); + this->dynsym_index_ = index; + } + + // Return the output virtual address of OFFSET relative to the start + // of input section SHNDX in object OBJECT. + uint64_t + output_address(const Relobj* object, unsigned int shndx, + off_t offset) const; + + // Set the address of the Output_section. For a typical + // Output_section, there is nothing to do, but if there are any + // Output_section_data objects we need to set the final addresses + // here. + void + do_set_address(uint64_t, off_t); + + // Write the data to the file. For a typical Output_section, this + // does nothing: the data is written out by calling Object::Relocate + // on each input object. But if there are any Output_section_data + // objects we do need to write them out here. + void + do_write(Output_file*); + + // Return the address alignment--function required by parent class. + uint64_t + do_addralign() const + { return this->addralign_; } + + // Return whether this is an Output_section. + bool + do_is_section() const + { return true; } + + // Return whether this is a section of the specified type. + bool + do_is_section_type(elfcpp::Elf_Word type) const + { return this->type_ == type; } + + // Return whether the specified section flag is set. + bool + do_is_section_flag_set(elfcpp::Elf_Xword flag) const + { return (this->flags_ & flag) != 0; } + + // Write the section header into *OPHDR. + template + void + write_header(const Layout*, const Stringpool*, + elfcpp::Shdr_write*) const; + private: + // In some cases we need to keep a list of the input sections + // associated with this output section. We only need the list if we + // might have to change the offsets of the input section within the + // output section after we add the input section. The ordinary + // input sections will be written out when we process the object + // file, and as such we don't need to track them here. We do need + // to track Output_section_data objects here. We store instances of + // this structure in a std::vector, so it must be a POD. There can + // be many instances of this structure, so we use a union to save + // some space. + class Input_section + { + public: + Input_section() + : shndx_(0), p2align_(0) + { + this->u1_.data_size = 0; + this->u2_.object = NULL; + } + + // For an ordinary input section. + Input_section(Relobj* object, unsigned int shndx, off_t data_size, + uint64_t addralign) + : shndx_(shndx), + p2align_(ffsll(static_cast(addralign))) + { + gold_assert(shndx != OUTPUT_SECTION_CODE + && shndx != MERGE_DATA_SECTION_CODE + && shndx != MERGE_STRING_SECTION_CODE); + this->u1_.data_size = data_size; + this->u2_.object = object; + } + + // For a non-merge output section. + Input_section(Output_section_data* posd) + : shndx_(OUTPUT_SECTION_CODE), + p2align_(ffsll(static_cast(posd->addralign()))) + { + this->u1_.data_size = 0; + this->u2_.posd = posd; + } + + // For a merge section. + Input_section(Output_section_data* posd, bool is_string, uint64_t entsize) + : shndx_(is_string + ? MERGE_STRING_SECTION_CODE + : MERGE_DATA_SECTION_CODE), + p2align_(ffsll(static_cast(posd->addralign()))) + { + this->u1_.entsize = entsize; + this->u2_.posd = posd; + } + + // The required alignment. + uint64_t + addralign() const + { + return (this->p2align_ == 0 + ? 0 + : static_cast(1) << (this->p2align_ - 1)); + } + + // Return the required size. + off_t + data_size() const; + + // Return whether this is a merge section which matches the + // parameters. + bool + is_merge_section(bool is_string, uint64_t entsize) const + { + return (this->shndx_ == (is_string + ? MERGE_STRING_SECTION_CODE + : MERGE_DATA_SECTION_CODE) + && this->u1_.entsize == entsize); + } + + // Set the output section. + void + set_output_section(Output_section* os) + { + gold_assert(!this->is_input_section()); + this->u2_.posd->set_output_section(os); + } + + // Set the address and file offset. This is called during + // Layout::finalize. SECOFF is the file offset of the enclosing + // section. + void + set_address(uint64_t addr, off_t off, off_t secoff); + + // Add an input section, for SHF_MERGE sections. + bool + add_input_section(Relobj* object, unsigned int shndx) + { + gold_assert(this->shndx_ == MERGE_DATA_SECTION_CODE + || this->shndx_ == MERGE_STRING_SECTION_CODE); + return this->u2_.posd->add_input_section(object, shndx); + } + + // Given an input OBJECT, an input section index SHNDX within that + // object, and an OFFSET relative to the start of that input + // section, return whether or not the output address is known. + // OUTPUT_SECTION_ADDRESS is the address of the output section + // which this is a part of. If this function returns true, it + // sets *POUTPUT to the output address. + bool + output_address(const Relobj* object, unsigned int shndx, off_t offset, + uint64_t output_section_address, uint64_t *poutput) const; + + // Write out the data. This does nothing for an input section. + void + write(Output_file*); + + private: + // Code values which appear in shndx_. If the value is not one of + // these codes, it is the input section index in the object file. + enum + { + // An Output_section_data. + OUTPUT_SECTION_CODE = -1U, + // An Output_section_data for an SHF_MERGE section with + // SHF_STRINGS not set. + MERGE_DATA_SECTION_CODE = -2U, + // An Output_section_data for an SHF_MERGE section with + // SHF_STRINGS set. + MERGE_STRING_SECTION_CODE = -3U + }; + + // Whether this is an input section. + bool + is_input_section() const + { + return (this->shndx_ != OUTPUT_SECTION_CODE + && this->shndx_ != MERGE_DATA_SECTION_CODE + && this->shndx_ != MERGE_STRING_SECTION_CODE); + } + + // For an ordinary input section, this is the section index in the + // input file. For an Output_section_data, this is + // OUTPUT_SECTION_CODE or MERGE_DATA_SECTION_CODE or + // MERGE_STRING_SECTION_CODE. + unsigned int shndx_; + // The required alignment, stored as a power of 2. + unsigned int p2align_; + union + { + // For an ordinary input section, the section size. + off_t data_size; + // For OUTPUT_SECTION_CODE, this is not used. For + // MERGE_DATA_SECTION_CODE or MERGE_STRING_SECTION_CODE, the + // entity size. + uint64_t entsize; + } u1_; + union + { + // For an ordinary input section, the object which holds the + // input section. + Relobj* object; + // For OUTPUT_SECTION_CODE or MERGE_DATA_SECTION_CODE or + // MERGE_STRING_SECTION_CODE, the data. + Output_section_data* posd; + } u2_; + }; + + typedef std::vector Input_section_list; + + // Add a new output section by Input_section. + void + add_output_section_data(Input_section*); + + // Add an SHF_MERGE input section. Returns true if the section was + // handled. + bool + add_merge_input_section(Relobj* object, unsigned int shndx, uint64_t flags, + uint64_t entsize, uint64_t addralign); + + // Add an output SHF_MERGE section POSD to this output section. + // IS_STRING indicates whether it is a SHF_STRINGS section, and + // ENTSIZE is the entity size. This returns the entry added to + // input_sections_. + void + add_output_merge_section(Output_section_data* posd, bool is_string, + uint64_t entsize); + // Most of these fields are only valid after layout. // The name of the section. This will point into a Stringpool. const char* name_; - // The section address. - uint64_t addr_; + // The section address is in the parent class. // The section alignment. uint64_t addralign_; // The section entry size. uint64_t entsize_; - // The file offset. - off_t offset_; - // The section size. - off_t size_; - // The section link field. + // The file offset is in the parent class. + // Set the section link field to the index of this section. + const Output_data* link_section_; + // If link_section_ is NULL, this is the link field. unsigned int link_; - // The section info field. + // Set the section info field to the index of this section. + const Output_data* info_section_; + // If info_section_ is NULL, this is the section info field. unsigned int info_; // The section type. elfcpp::Elf_Word type_; // The section flags. elfcpp::Elf_Xword flags_; + // The section index. + unsigned int out_shndx_; + // If there is a STT_SECTION for this output section in the normal + // symbol table, this is the symbol index. This starts out as zero. + // It is initialized in Layout::finalize() to be the index, or -1U + // if there isn't one. + unsigned int symtab_index_; + // If there is a STT_SECTION for this output section in the dynamic + // symbol table, this is the symbol index. This starts out as zero. + // It is initialized in Layout::finalize() to be the index, or -1U + // if there isn't one. + unsigned int dynsym_index_; + // The input sections. This will be empty in cases where we don't + // need to keep track of them. + Input_section_list input_sections_; + // The offset of the first entry in input_sections_. + off_t first_input_offset_; + // Whether this output section needs a STT_SECTION symbol in the + // normal symbol table. This will be true if there is a relocation + // which needs it. + bool needs_symtab_index_ : 1; + // Whether this output section needs a STT_SECTION symbol in the + // dynamic symbol table. This will be true if there is a dynamic + // relocation which needs it. + bool needs_dynsym_index_ : 1; + // Whether the link field of this output section should point to the + // normal symbol table. + bool should_link_to_symtab_ : 1; + // Whether the link field of this output section should point to the + // dynamic symbol table. + bool should_link_to_dynsym_ : 1; }; // An output segment. PT_LOAD segments are built from collections of @@ -158,24 +1632,99 @@ class Output_segment flags() const { return this->flags_; } + // Return the memory size. + uint64_t + memsz() const + { return this->memsz_; } + + // Return the file size. + off_t + filesz() const + { return this->filesz_; } + + // Return the maximum alignment of the Output_data. + uint64_t + addralign(); + // Add an Output_section to this segment. void - add_output_section(Output_section*); + add_output_section(Output_section* os, elfcpp::Elf_Word seg_flags) + { this->add_output_section(os, seg_flags, false); } + + // Add an Output_section to the start of this segment. + void + add_initial_output_section(Output_section* os, elfcpp::Elf_Word seg_flags) + { this->add_output_section(os, seg_flags, true); } + + // Add an Output_data (which is not an Output_section) to the start + // of this segment. + void + add_initial_output_data(Output_data*); + + // Set the address of the segment to ADDR and the offset to *POFF + // (aligned if necessary), and set the addresses and offsets of all + // contained output sections accordingly. Set the section indexes + // of all contained output sections starting with *PSHNDX. Return + // the address of the immediately following segment. Update *POFF + // and *PSHNDX. This should only be called for a PT_LOAD segment. + uint64_t + set_section_addresses(uint64_t addr, off_t* poff, unsigned int* pshndx); + + // Set the offset of this segment based on the section. This should + // only be called for a non-PT_LOAD segment. + void + set_offset(); + + // Return the number of output sections. + unsigned int + output_section_count() const; - // Update the segment flags to be compatible with FLAGS. + // Write the segment header into *OPHDR. + template void - update_flags(elfcpp::Elf_Word flags) - { this->flags_ |= flags & (elfcpp::PF_R | elfcpp::PF_W | elfcpp::PF_X); } + write_header(elfcpp::Phdr_write*); + + // Write the section headers of associated sections into V. + template + unsigned char* + write_section_headers(const Layout*, const Stringpool*, unsigned char* v, + unsigned int* pshndx ACCEPT_SIZE_ENDIAN) const; private: Output_segment(const Output_segment&); Output_segment& operator=(const Output_segment&); - typedef std::list Section_list; + typedef std::list Output_data_list; - // The list of output sections attached to this segment. This is - // cleared after layout. - Section_list output_sections_; + // Add an Output_section to this segment, specifying front or back. + void + add_output_section(Output_section*, elfcpp::Elf_Word seg_flags, + bool front); + + // Find the maximum alignment in an Output_data_list. + static uint64_t + maximum_alignment(const Output_data_list*); + + // Set the section addresses in an Output_data_list. + uint64_t + set_section_list_addresses(Output_data_list*, uint64_t addr, off_t* poff, + unsigned int* pshndx); + + // Return the number of Output_sections in an Output_data_list. + unsigned int + output_section_count_list(const Output_data_list*) const; + + // Write the section headers in the list into V. + template + unsigned char* + write_section_headers_list(const Layout*, const Stringpool*, + const Output_data_list*, unsigned char* v, + unsigned int* pshdx ACCEPT_SIZE_ENDIAN) const; + + // The list of output data with contents attached to this segment. + Output_data_list output_data_; + // The list of output data without contents attached to this segment. + Output_data_list output_bss_; // The segment virtual address. uint64_t vaddr_; // The segment physical address. @@ -192,21 +1741,59 @@ class Output_segment elfcpp::Elf_Word type_; // The segment flags. elfcpp::Elf_Word flags_; + // Whether we have set align_. + bool is_align_known_; }; -// This class represents the output file. The output file is a -// collection of output segments and a collection of output sections -// which are not associated with segments. +// This class represents the output file. class Output_file { public: - Output_file(); - ~Output_file(); + Output_file(const General_options& options); + + // Open the output file. FILE_SIZE is the final size of the file. + void + open(off_t file_size); + + // Close the output file and make sure there are no error. + void + close(); + + // We currently always use mmap which makes the view handling quite + // simple. In the future we may support other approaches. // Write data to the output file. void - write(off_t off, const void* data, off_t len); + write(off_t offset, const void* data, off_t len) + { memcpy(this->base_ + offset, data, len); } + + // Get a buffer to use to write to the file, given the offset into + // the file and the size. + unsigned char* + get_output_view(off_t start, off_t size) + { + gold_assert(start >= 0 && size >= 0 && start + size <= this->file_size_); + return this->base_ + start; + } + + // VIEW must have been returned by get_output_view. Write the + // buffer to the file, passing in the offset and the size. + void + write_output_view(off_t, off_t, unsigned char*) + { } + + private: + // General options. + const General_options& options_; + // File name. + const char* name_; + // File descriptor. + int o_; + // File size. + off_t file_size_; + // Base of file mapped into memory. + unsigned char* base_; }; } // End namespace gold.