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author | Ian Lance Taylor <iant@google.com> | 2006-11-16 00:38:25 +0000 |
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committer | Ian Lance Taylor <iant@google.com> | 2006-11-16 00:38:25 +0000 |
commit | c06b7b0ba3f6aaa4a3f9586689ef8bfdbd17454e (patch) | |
tree | 732f3a1719d66e1fd993872ecd58ca282d2858f8 /gold/output.h | |
parent | 7495b3afc0d28e2d64995f383e2436a35aa14e6d (diff) | |
download | gdb-c06b7b0ba3f6aaa4a3f9586689ef8bfdbd17454e.zip gdb-c06b7b0ba3f6aaa4a3f9586689ef8bfdbd17454e.tar.gz gdb-c06b7b0ba3f6aaa4a3f9586689ef8bfdbd17454e.tar.bz2 |
Snapshot. Includes first cut at output relocation sections.
Diffstat (limited to 'gold/output.h')
-rw-r--r-- | gold/output.h | 367 |
1 files changed, 353 insertions, 14 deletions
diff --git a/gold/output.h b/gold/output.h index 9763d74..c31640f 100644 --- a/gold/output.h +++ b/gold/output.h @@ -9,6 +9,7 @@ #include "elfcpp.h" #include "layout.h" +#include "reloc-types.h" namespace gold { @@ -16,9 +17,11 @@ namespace gold class General_options; class Object; class Output_file; - +class Output_section; template<int size, bool big_endian> class Sized_target; +template<int size, bool big_endian> +class Sized_relobj; // An abtract class for data which has to go into the output file. @@ -361,6 +364,262 @@ class Output_data_common : public Output_section_data { } }; +// 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<int sh_type, bool dynamic, int size, bool big_endian> +class Output_reloc; + +template<bool dynamic, int size, bool big_endian> +class Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian> +{ + public: + typedef typename elfcpp::Elf_types<size>::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, Address address) + : local_sym_index_(GSYM_CODE), type_(type), address_(address) + { this->u_.gsym = gsym; } + + // A reloc against a local symbol. + Output_reloc(Sized_relobj<size, big_endian>* object, + unsigned int local_sym_index, + unsigned int type, Address address) + : local_sym_index_(local_sym_index), type_(type), address_(address) + { + assert(local_sym_index != GSYM_CODE && local_sym_index != INVALID_CODE); + this->u_.object = object; + } + + // A reloc against the STT_SECTION symbol of an output section. + Output_reloc(Output_section* os, unsigned int type, Address address) + : local_sym_index_(SECTION_CODE), type_(type), address_(address) + { this->u_.os = os; } + + // Write the reloc entry to an output view. + void + write(unsigned char* pov) const; + + // Write the offset and info fields to Write_rel. + template<typename Write_rel> + 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<size, big_endian>* object; + // 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; + } u_; + // 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_; + unsigned int type_; + Address address_; +}; + +// 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<bool dynamic, int size, bool big_endian> +class Output_reloc<elfcpp::SHT_RELA, dynamic, size, big_endian> +{ + public: + typedef typename elfcpp::Elf_types<size>::Elf_Addr Address; + typedef typename elfcpp::Elf_types<size>::Elf_Addr Addend; + + // An uninitialized entry. + Output_reloc() + : rel_() + { } + + // A reloc against a global symbol. + Output_reloc(Symbol* gsym, unsigned int type, Address address, Addend addend) + : rel_(gsym, type, address), addend_(addend) + { } + + // A reloc against a local symbol. + Output_reloc(Sized_relobj<size, big_endian>* object, + unsigned int local_sym_index, + unsigned int type, Address address, Addend addend) + : rel_(object, local_sym_index, type, address), addend_(addend) + { } + + // A reloc against the STT_SECTION symbol of an output section. + Output_reloc(Output_section* os, unsigned int type, Address address, + Addend addend) + : rel_(os, type, address), addend_(addend) + { } + + // Write the reloc entry to an output view. + void + write(unsigned char* pov) const; + + private: + // The basic reloc. + Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian> 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<int sh_type, bool dynamic, int size, bool big_endian> +class Output_data_reloc_base : public Output_section_data +{ + public: + typedef Output_reloc<sh_type, dynamic, size, big_endian> Output_reloc_type; + typedef typename Output_reloc_type::Address Address; + static const int reloc_size = + Reloc_types<sh_type, size, big_endian>::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: + // 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<Output_reloc_type> Relocs; + + Relocs relocs_; +}; + +// The class which callers actually create. + +template<int sh_type, bool dynamic, int size, bool big_endian> +class Output_data_reloc; + +// The SHT_REL version of Output_data_reloc. + +template<bool dynamic, int size, bool big_endian> +class Output_data_reloc<elfcpp::SHT_REL, dynamic, size, big_endian> + : public Output_data_reloc_base<elfcpp::SHT_REL, dynamic, size, big_endian> +{ + private: + typedef Output_data_reloc_base<elfcpp::SHT_REL, dynamic, size, + big_endian> 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<elfcpp::SHT_REL, dynamic, size, big_endian>() + { } + + // Add a reloc against a global symbol. + void + add_global(Symbol* gsym, unsigned int type, Address address) + { this->add(Output_reloc_type(gsym, type, address)); } + + // Add a reloc against a local symbol. + void + add_local(Sized_relobj<size, big_endian>* object, + unsigned int local_sym_index, unsigned int type, Address address) + { this->add(Output_reloc_type(object, local_sym_index, type, address)); } + + // A reloc against the STT_SECTION symbol of an output section. + void + add_output_section(Output_section* os, unsigned int type, Address address) + { this->add(Output_reloc_type(os, type, address)); } +}; + +// The SHT_RELA version of Output_data_reloc. + +template<bool dynamic, int size, bool big_endian> +class Output_data_reloc<elfcpp::SHT_RELA, dynamic, size, big_endian> + : public Output_data_reloc_base<elfcpp::SHT_RELA, dynamic, size, big_endian> +{ + private: + typedef Output_data_reloc_base<elfcpp::SHT_RELA, dynamic, size, + big_endian> 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<elfcpp::SHT_RELA, dynamic, size, big_endian>() + { } + + // Add a reloc against a global symbol. + void + add_global(Symbol* gsym, unsigned int type, Address address, Addend addend) + { this->add(Output_reloc_type(gsym, type, address, addend)); } + + // Add a reloc against a local symbol. + void + add_local(Sized_relobj<size, big_endian>* object, + unsigned int local_sym_index, unsigned int type, + Address address, Addend addend) + { + this->add(Output_reloc_type(object, local_sym_index, type, address, + addend)); + } + + // A reloc against the STT_SECTION symbol of an output section. + void + add_output_section(Output_section* os, unsigned int type, Address address, + Addend addend) + { this->add(Output_reloc_type(os, type, 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 @@ -456,8 +715,8 @@ class Output_data_got : public Output_section_data // For a constant, the constant. Valtype constant; } u_; - // For a local symbol, the local symbol index. This is -1U for a - // global symbol, or -2U for a constant. + // 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_; }; @@ -501,7 +760,7 @@ class Output_section : public Output_data const elfcpp::Shdr<size, big_endian>& shdr); // Add generated data ODATA to this output section. - virtual void + void add_output_section_data(Output_section_data* posd); // Return the section name. @@ -549,6 +808,58 @@ class Output_section : public Output_data 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 + { + assert(this->symtab_index_ != 0); + return this->symtab_index_; + } + + // Set the symtab index. + void + set_symtab_index(unsigned int index) + { + 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 + { + assert(this->dynsym_index_ != 0); + return this->dynsym_index_; + } + + // Set the dynsym index. + void + set_dynsym_index(unsigned int index) + { + assert(index != 0); + this->dynsym_index_ = index; + } + // 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 @@ -686,13 +997,31 @@ class Output_section : public Output_data 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 we permit adding data. - bool may_add_data_; + bool may_add_data_ : 1; + // 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; }; // A special Output_section which represents the symbol table @@ -702,18 +1031,33 @@ class Output_section : public Output_data class Output_section_symtab : public Output_section { public: - Output_section_symtab(const char* name, off_t size); + Output_section_symtab(const char* name, off_t data_size) + : Output_section(name, elfcpp::SHT_SYMTAB, 0, false) + { this->set_data_size(data_size); } // The data is written out by Symbol_table::write_globals. We don't // do anything here. void do_write(Output_file*) { } +}; + +// A special Output_section which represents the dynamic symbol table +// (SHT_DYNSYM). The actual data is written out by +// Symbol_table::write_globals. + +class Output_section_dynsym : public Output_section +{ + public: + Output_section_dynsym(const char* name, off_t data_size) + : Output_section(name, elfcpp::SHT_DYNSYM, 0, false) + { this->set_data_size(data_size); } - // We don't expect to see any input sections or data here. + // The data is written out by Symbol_table::write_globals. We don't + // do anything here. void - add_output_section_data(Output_section_data*) - { abort(); } + do_write(Output_file*) + { } }; // A special Output_section which holds a string table. @@ -727,11 +1071,6 @@ class Output_section_strtab : public Output_section void do_write(Output_file*); - // We don't expect to see any input sections or data here. - void - add_output_section_data(Output_section_data*) - { abort(); } - private: Stringpool* contents_; }; |