diff options
author | Ian Lance Taylor <iant@google.com> | 2006-10-20 20:40:49 +0000 |
---|---|---|
committer | Ian Lance Taylor <iant@google.com> | 2006-10-20 20:40:49 +0000 |
commit | 92e059d8dc78c3f65e29e48e368f6e47ea0ab671 (patch) | |
tree | f448eb3317d9cbb0f5946422cc28ef157a5f65cb /gold/reloc.h | |
parent | af4658dc3db33004d6166b161588221ecb463a5f (diff) | |
download | gdb-92e059d8dc78c3f65e29e48e368f6e47ea0ab671.zip gdb-92e059d8dc78c3f65e29e48e368f6e47ea0ab671.tar.gz gdb-92e059d8dc78c3f65e29e48e368f6e47ea0ab671.tar.bz2 |
Framework for relocation scanning. Implement simple static TLS
relocations.
Diffstat (limited to 'gold/reloc.h')
-rw-r--r-- | gold/reloc.h | 506 |
1 files changed, 503 insertions, 3 deletions
diff --git a/gold/reloc.h b/gold/reloc.h index 287bb79..a2e9d54 100644 --- a/gold/reloc.h +++ b/gold/reloc.h @@ -3,18 +3,98 @@ #ifndef GOLD_RELOC_H #define GOLD_RELOC_H +#include <byteswap.h> + #include "workqueue.h" namespace gold { +class Object; +class Read_relocs_data; +class Stringpool; + +// A class to read the relocations for an object file, and then queue +// up a task to see if they require any GOT/PLT/COPY relocations in +// the symbol table. + +class Read_relocs : public Task +{ + public: + // SYMTAB_LOCK is used to lock the symbol table. BLOCKER should be + // unblocked when the Scan_relocs task completes. + Read_relocs(const General_options& options, Symbol_table* symtab, + Object* object, Task_token* symtab_lock, + Task_token* blocker) + : options_(options), symtab_(symtab), object_(object), + symtab_lock_(symtab_lock), blocker_(blocker) + { } + + // The standard Task methods. + + Is_runnable_type + is_runnable(Workqueue*); + + Task_locker* + locks(Workqueue*); + + void + run(Workqueue*); + + private: + const General_options& options_; + Symbol_table* symtab_; + Object* object_; + Task_token* symtab_lock_; + Task_token* blocker_; +}; + +// Scan the relocations for an object to see if they require any +// GOT/PLT/COPY relocations. + +class Scan_relocs : public Task +{ + public: + // SYMTAB_LOCK is used to lock the symbol table. BLOCKER should be + // unblocked when the task completes. + Scan_relocs(const General_options& options, Symbol_table* symtab, + Object* object, Read_relocs_data* rd, Task_token* symtab_lock, + Task_token* blocker) + : options_(options), symtab_(symtab), object_(object), rd_(rd), + symtab_lock_(symtab_lock), blocker_(blocker) + { } + + // The standard Task methods. + + Is_runnable_type + is_runnable(Workqueue*); + + Task_locker* + locks(Workqueue*); + + void + run(Workqueue*); + + private: + class Scan_relocs_locker; + + const General_options& options_; + Symbol_table* symtab_; + Object* object_; + Read_relocs_data* rd_; + Task_token* symtab_lock_; + Task_token* blocker_; +}; + +// A class to perform all the relocations for an object file. + class Relocate_task : public Task { public: Relocate_task(const General_options& options, const Symbol_table* symtab, - const Stringpool* sympool, Object* object, Output_file* of, + const Layout* layout, Object* object, Output_file* of, Task_token* final_blocker) - : options_(options), symtab_(symtab), sympool_(sympool), object_(object), + : options_(options), symtab_(symtab), layout_(layout), object_(object), of_(of), final_blocker_(final_blocker) { } @@ -34,12 +114,432 @@ class Relocate_task : public Task const General_options& options_; const Symbol_table* symtab_; - const Stringpool* sympool_; + const Layout* layout_; Object* object_; Output_file* of_; Task_token* final_blocker_; }; +// Integer swapping routines used by relocation functions. FIXME: +// Maybe these should be more general, and/or shared with elfcpp. + +// Endian simply indicates whether the host is big endian or not, +// based on the results of the configure script. + +struct Endian +{ + public: + // Used for template specializations. +#ifdef WORDS_BIGENDIAN + static const bool host_big_endian = true; +#else + static const bool host_big_endian = false; +#endif +}; + +// Valtype_base is a template based on size (8, 16, 32, 64) which +// defines a typedef Valtype for the unsigned integer of the specified +// size. + +template<int size> +struct Valtype_base; + +template<> +struct Valtype_base<8> +{ + typedef unsigned char Valtype; +}; + +template<> +struct Valtype_base<16> +{ + typedef uint16_t Valtype; +}; + +template<> +struct Valtype_base<32> +{ + typedef uint32_t Valtype; +}; + +template<> +struct Valtype_base<64> +{ + typedef uint64_t Valtype; +}; + +// Convert_host is a template based on size and on whether the host +// and target have the same endianness. It defines the type Valtype, +// and defines a function convert_host which takes an argument of type +// Valtype and swaps it if the host and target have different +// endianness. + +template<int size, bool same_endian> +struct Convert_host; + +template<int size> +struct Convert_host<size, true> +{ + typedef typename Valtype_base<size>::Valtype Valtype; + + static inline Valtype + convert_host(Valtype v) + { return v; } +}; + +template<> +struct Convert_host<8, false> +{ + typedef Valtype_base<8>::Valtype Valtype; + + static inline Valtype + convert_host(Valtype v) + { return v; } +}; + +template<> +struct Convert_host<16, false> +{ + typedef Valtype_base<16>::Valtype Valtype; + + static inline Valtype + convert_host(Valtype v) + { return bswap_16(v); } +}; + +template<> +struct Convert_host<32, false> +{ + typedef Valtype_base<32>::Valtype Valtype; + + static inline Valtype + convert_host(Valtype v) + { return bswap_32(v); } +}; + +template<> +struct Convert_host<64, false> +{ + typedef Valtype_base<64>::Valtype Valtype; + + static inline Valtype + convert_host(Valtype v) + { return bswap_64(v); } +}; + +// Convert is a template based on size and on whether we have a big +// endian target. It defines Valtype and convert_host like +// Convert_host. That is, it is just like Convert_host except in the +// meaning of the second template parameter. + +template<int size, bool big_endian> +struct Convert +{ + typedef typename Valtype_base<size>::Valtype Valtype; + + static inline Valtype + convert_host(Valtype v) + { return Convert_host<size, big_endian == Endian::host_big_endian> + ::convert_host(v); } +}; + +// Swap is a template based on size and on whether the target is big +// endian. It defines the type Valtype and the functions readval and +// writeval. The functions read and write values of the appropriate +// size out of buffers, swapping them if necessary. + +template<int size, bool big_endian> +struct Swap +{ + typedef typename Valtype_base<size>::Valtype Valtype; + + static inline Valtype + readval(const Valtype* wv) + { return Convert<size, big_endian>::convert_host(*wv); } + + static inline void + writeval(Valtype* wv, Valtype v) + { *wv = Convert<size, big_endian>::convert_host(v); } +}; + +// Swap_unaligned is a template based on size and on whether the +// target is big endian. It defines the type Valtype and the +// functions readval_unaligned and writeval_unaligned. The functions +// read and write values of the appropriate size out of buffers which +// may be misaligned. + +template<int size, bool big_endian> +class Swap_unaligned; + +template<bool big_endian> +class Swap_unaligned<8, big_endian> +{ +public: + typedef typename Valtype_base<8>::Valtype Valtype; + + static inline Valtype + readval_unaligned(const unsigned char* wv) + { return *wv; } + + static inline void + writeval_unaligned(unsigned char* wv, Valtype v) + { *wv = v; } +}; + +template<> +class Swap_unaligned<16, false> +{ +public: + typedef Valtype_base<16>::Valtype Valtype; + + static inline Valtype + readval_unaligned(const unsigned char* wv) + { + return (wv[1] << 8) | wv[0]; + } + + static inline void + writeval_unaligned(unsigned char* wv, Valtype v) + { + wv[1] = v >> 8; + wv[0] = v; + } +}; + +template<> +class Swap_unaligned<16, true> +{ +public: + typedef Valtype_base<16>::Valtype Valtype; + + static inline Valtype + readval_unaligned(const unsigned char* wv) + { + return (wv[0] << 8) | wv[1]; + } + + static inline void + writeval_unaligned(unsigned char* wv, Valtype v) + { + wv[0] = v >> 8; + wv[1] = v; + } +}; + +template<> +class Swap_unaligned<32, false> +{ +public: + typedef Valtype_base<32>::Valtype Valtype; + + static inline Valtype + readval_unaligned(const unsigned char* wv) + { + return (wv[3] << 24) | (wv[2] << 16) | (wv[1] << 8) | wv[0]; + } + + static inline void + writeval_unaligned(unsigned char* wv, Valtype v) + { + wv[3] = v >> 24; + wv[2] = v >> 16; + wv[1] = v >> 8; + wv[0] = v; + } +}; + +template<> +class Swap_unaligned<32, true> +{ +public: + typedef Valtype_base<32>::Valtype Valtype; + + static inline Valtype + readval_unaligned(const unsigned char* wv) + { + return (wv[0] << 24) | (wv[1] << 16) | (wv[2] << 8) | wv[3]; + } + + static inline void + writeval_unaligned(unsigned char* wv, Valtype v) + { + wv[0] = v >> 24; + wv[1] = v >> 16; + wv[2] = v >> 8; + wv[3] = v; + } +}; + +template<> +class Swap_unaligned<64, false> +{ +public: + typedef Valtype_base<64>::Valtype Valtype; + + static inline Valtype + readval_unaligned(const unsigned char* wv) + { + return ((static_cast<Valtype>(wv[7]) << 56) + | (static_cast<Valtype>(wv[6]) << 48) + | (static_cast<Valtype>(wv[5]) << 40) + | (static_cast<Valtype>(wv[4]) << 32) + | (static_cast<Valtype>(wv[3]) << 24) + | (static_cast<Valtype>(wv[2]) << 16) + | (static_cast<Valtype>(wv[1]) << 8) + | static_cast<Valtype>(wv[0])); + } + + static inline void + writeval_unaligned(unsigned char* wv, Valtype v) + { + wv[7] = v >> 56; + wv[6] = v >> 48; + wv[5] = v >> 40; + wv[4] = v >> 32; + wv[3] = v >> 24; + wv[2] = v >> 16; + wv[1] = v >> 8; + wv[0] = v; + } +}; + +template<> +class Swap_unaligned<64, true> +{ +public: + typedef Valtype_base<64>::Valtype Valtype; + + static inline Valtype + readval_unaligned(const unsigned char* wv) + { + return ((static_cast<Valtype>(wv[0]) << 56) + | (static_cast<Valtype>(wv[1]) << 48) + | (static_cast<Valtype>(wv[2]) << 40) + | (static_cast<Valtype>(wv[3]) << 32) + | (static_cast<Valtype>(wv[4]) << 24) + | (static_cast<Valtype>(wv[5]) << 16) + | (static_cast<Valtype>(wv[6]) << 8) + | static_cast<Valtype>(wv[7])); + } + + static inline void + writeval_unaligned(unsigned char* wv, Valtype v) + { + wv[7] = v >> 56; + wv[6] = v >> 48; + wv[5] = v >> 40; + wv[4] = v >> 32; + wv[3] = v >> 24; + wv[2] = v >> 16; + wv[1] = v >> 8; + wv[0] = v; + } +}; + +// Standard relocation routines which are used on many targets. Here +// SIZE and BIG_ENDIAN refer to the target, not the relocation type. + +template<int size, bool big_endian> +class Relocate_functions +{ +private: + // Do a simple relocation with the addend in the section contents. + // VALSIZE is the size of the value. + template<int valsize> + static inline void + rel(unsigned char* view, typename Swap<valsize, big_endian>::Valtype value) + { + typedef typename Swap<valsize, big_endian>::Valtype Valtype; + Valtype* wv = reinterpret_cast<Valtype*>(view); + Valtype x = Swap<valsize, big_endian>::readval(wv); + Swap<valsize, big_endian>::writeval(wv, x + value); + } + + // Do a simple PC relative relocation with the addend in the section + // contents. VALSIZE is the size of the value. + template<int valsize> + static inline void + pcrel(unsigned char* view, typename Swap<valsize, big_endian>::Valtype value, + typename elfcpp::Elf_types<size>::Elf_Addr address) + { + typedef typename Swap<valsize, big_endian>::Valtype Valtype; + Valtype* wv = reinterpret_cast<Valtype*>(view); + Valtype x = Swap<valsize, big_endian>::readval(wv); + Swap<valsize, big_endian>::writeval(wv, x + value - address); + } + + typedef Relocate_functions<size, big_endian> This; + +public: + // Do a simple 8-bit REL relocation with the addend in the object + // file data. + static inline void + rel8(unsigned char* view, unsigned char value) + { + This::template rel<8>(view, value); + } + + // Do a simple 8-bit PC relative relocation with the addend in the + // object file data. + static inline void + pcrel8(unsigned char* view, unsigned char value, + typename elfcpp::Elf_types<size>::Elf_Addr address) + { + This::template pcrel<8>(view, value, address); + } + + // Do a simple 16-bit REL relocation with the addend in the object + // file data. + static inline void + rel16(unsigned char* view, elfcpp::Elf_Half value) + { + This::template rel<16>(view, value); + } + + // Do a simple 32-bit PC relative REL relocation with the addend in + // the object file data. + static inline void + pcrel16(unsigned char* view, elfcpp::Elf_Word value, + typename elfcpp::Elf_types<size>::Elf_Addr address) + { + This::template pcrel<16>(view, value, address); + } + + // Do a simple 32-bit REL relocation with the addend in the section + // contents. + static inline void + rel32(unsigned char* view, elfcpp::Elf_Word value) + { + This::template rel<32>(view, value); + } + + // Do a simple 32-bit PC relative REL relocation with the addend in + // the section contents. + static inline void + pcrel32(unsigned char* view, elfcpp::Elf_Word value, + typename elfcpp::Elf_types<size>::Elf_Addr address) + { + This::template pcrel<32>(view, value, address); + } + + // Do a simple 64-bit REL relocation with the addend in the section + // contents. + static inline void + rel64(unsigned char* view, elfcpp::Elf_Word value) + { + This::template rel<64>(view, value); + } + + // Do a simple 64-bit PC relative REL relocation with the addend in + // the section contents. + static inline void + pcrel64(unsigned char* view, elfcpp::Elf_Word value, + typename elfcpp::Elf_types<size>::Elf_Addr address) + { + This::template pcrel<64>(view, value, address); + } +}; + } // End namespace gold. #endif // !defined(GOLD_RELOC_H) |