gold/i386.cc

   1 // i386.cc -- i386 target support for gold.
   2
   3 #include "gold.h"
   4 #include "elfcpp.h"
   5 #include "i386.h"
   6 #include "object.h"
   7 #include "target.h"
   8 #include "target-reloc.h"
   9 #include "target-select.h"
  10
  11 namespace
  12 {
  13
  14 using namespace gold;
  15
  16 // The i386 target class.
  17
  18 class Target_i386 : public Sized_target<32, false>
  19 {
  20  public:
  21   Target_i386()
  22     : Sized_target<32, false>(&i386_info)
  23   { }
  24
  25   void
  26   relocate_section(const Symbol_table* symtab,
  27                    Sized_object<32, false>*,
  28                    unsigned int,
  29                    const unsigned char*,
  30                    size_t,
  31                    unsigned int,
  32                    const elfcpp::Elf_types<32>::Elf_Addr*,
  33                    Symbol**,
  34                    unsigned char*,
  35                    elfcpp::Elf_types<32>::Elf_Addr,
  36                    off_t);
  37
  38   // The class which implements relocation.
  39   struct Relocate
  40   {
  41     inline void
  42     operator()(Sized_object<32, false>*, const elfcpp::Rel<32, false>&,
  43                unsigned int r_type, Sized_symbol<32>*,
  44                elfcpp::Elf_types<32>::Elf_Addr,
  45                unsigned char*, elfcpp::Elf_types<32>::Elf_Addr);
  46
  47   };
  48
  49  private:
  50   static const Target::Target_info i386_info;
  51 };
  52
  53 const Target::Target_info Target_i386::i386_info =
  54 {
  55   32,                   // size
  56   false,                // is_big_endian
  57   elfcpp::EM_386,       // machine_code
  58   false,                // has_make_symbol
  59   false,                // has_resolve,
  60   0x08048000,           // text_segment_address,
  61   0x1000,               // abi_pagesize
  62   0x1000                // common_pagesize
  63 };
  64
  65 // Perform a relocation.
  66
  67 inline void
  68 Target_i386::Relocate::operator()(Sized_object<32, false>* object,
  69                                   const elfcpp::Rel<32, false>&,
  70                                   unsigned int r_type,
  71                                   Sized_symbol<32>*,
  72                                   elfcpp::Elf_types<32>::Elf_Addr value,
  73                                   unsigned char* view,
  74                                   elfcpp::Elf_types<32>::Elf_Addr address)
  75 {
  76   switch (r_type)
  77     {
  78     case elfcpp::R_386_NONE:
  79       break;
  80
  81     case elfcpp::R_386_32:
  82       {
  83         elfcpp::Elf_Word* wv = reinterpret_cast<elfcpp::Elf_Word*>(view);
  84         unsigned int x = elfcpp::read_elf_word<false>(wv);
  85         elfcpp::write_elf_word<false>(wv, x + value);
  86       }
  87       break;
  88
  89     case elfcpp::R_386_PC32:
  90       {
  91         elfcpp::Elf_Word* wv = reinterpret_cast<elfcpp::Elf_Word*>(view);
  92         unsigned int x = elfcpp::read_elf_word<false>(wv);
  93         elfcpp::write_elf_word<false>(wv, x + value - address);
  94       }
  95       break;
  96
  97     default:
  98       fprintf(stderr, _("%s: %s: unsupported reloc %u\n"),
  99               program_name, object->name().c_str(), r_type);
 100       // gold_exit(false);
 101     }
 102 }
 103
 104 // Relocate section data.
 105
 106 void
 107 Target_i386::relocate_section(const Symbol_table* symtab,
 108                               Sized_object<32, false>* object,
 109                               unsigned int sh_type,
 110                               const unsigned char* prelocs,
 111                               size_t reloc_count,
 112                               unsigned int local_count,
 113                               const elfcpp::Elf_types<32>::Elf_Addr* values,
 114                               Symbol** global_syms,
 115                               unsigned char* view,
 116                               elfcpp::Elf_types<32>::Elf_Addr address,
 117                               off_t view_size)
 118 {
 119   if (sh_type == elfcpp::SHT_RELA)
 120     {
 121       fprintf(stderr, _("%s: %s: unsupported RELA reloc section\n"),
 122               program_name, object->name().c_str());
 123       gold_exit(false);
 124     }
 125
 126   gold::relocate_section<32, false, elfcpp::SHT_REL, Target_i386::Relocate>(
 127     symtab,
 128     object,
 129     prelocs,
 130     reloc_count,
 131     local_count,
 132     values,
 133     global_syms,
 134     view,
 135     address,
 136     view_size);
 137 }
 138
 139 // The i386 target.
 140
 141 Target_i386 target_i386;
 142
 143 // The selector for i386 object files.
 144
 145 class Target_selector_i386 : public Target_selector
 146 {
 147 public:
 148   Target_selector_i386()
 149     : Target_selector(elfcpp::EM_386, 32, false)
 150   { }
 151
 152   Target*
 153   recognize(int machine, int osabi, int abiversion) const;
 154 };
 155
 156 // Recognize an i386 object file when we already know that the machine
 157 // number is EM_386.
 158
 159 Target*
 160 Target_selector_i386::recognize(int, int, int) const
 161 {
 162   return &target_i386;
 163 }
 164
 165 Target_selector_i386 target_selector_i386;
 166
 167 } // End anonymous namespace.