1 //===- X86LDBackend.h -----------------------------------------------------===// 2 // 3 // The MCLinker Project 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 #ifndef X86_LDBACKEND_H 10 #define X86_LDBACKEND_H 11 12 #include "X86ELFDynamic.h" 13 #include "X86GOT.h" 14 #include "X86GOTPLT.h" 15 #include "X86PLT.h" 16 #include <mcld/LD/LDSection.h> 17 #include <mcld/Target/GNULDBackend.h> 18 #include <mcld/Target/OutputRelocSection.h> 19 20 namespace mcld { 21 22 class LinkerConfig; 23 class GNUInfo; 24 25 //===----------------------------------------------------------------------===// 26 /// X86GNULDBackend - linker backend of X86 target of GNU ELF format 27 /// 28 class X86GNULDBackend : public GNULDBackend 29 { 30 public: 31 X86GNULDBackend(const LinkerConfig& pConfig, 32 GNUInfo* pInfo, 33 Relocation::Type pCopyRel); 34 35 ~X86GNULDBackend(); 36 37 uint32_t machine() const; 38 39 X86PLT& getPLT(); 40 41 const X86PLT& getPLT() const; 42 43 /// preLayout - Backend can do any needed modification before layout 44 void doPreLayout(IRBuilder& pBuilder); 45 46 /// postLayout -Backend can do any needed modification after layout 47 void doPostLayout(Module& pModule, IRBuilder& pBuilder); 48 49 /// dynamic - the dynamic section of the target machine. 50 /// Use co-variant return type to return its own dynamic section. 51 X86ELFDynamic& dynamic(); 52 53 /// dynamic - the dynamic section of the target machine. 54 /// Use co-variant return type to return its own dynamic section. 55 const X86ELFDynamic& dynamic() const; 56 57 /// emitSectionData - write out the section data into the memory region. 58 /// When writers get a LDSection whose kind is LDFileFormat::Target, writers 59 /// call back target backend to emit the data. 60 /// 61 /// Backends handle the target-special tables (plt, gp,...) by themselves. 62 /// Backend can put the data of the tables in MCSectionData directly 63 /// - LDSection.getSectionData can get the section data. 64 /// Or, backend can put the data into special data structure 65 /// - backend can maintain its own map<LDSection, table> to get the table 66 /// from given LDSection. 67 /// 68 /// @param pSection - the given LDSection 69 /// @param pLayout - for comouting the size of fragment 70 /// @param pRegion - the region to write out data 71 /// @return the size of the table in the file. 72 uint64_t emitSectionData(const LDSection& pSection, 73 MemoryRegion& pRegion) const; 74 75 /// initRelocator - create and initialize Relocator. 76 virtual bool initRelocator() = 0; 77 78 /// getRelocator - return relocator. 79 Relocator* getRelocator(); 80 81 virtual void initTargetSections(Module& pModule, ObjectBuilder& pBuilder) = 0; 82 83 void initTargetSymbols(IRBuilder& pBuilder, Module& pModule); 84 85 OutputRelocSection& getRelDyn(); 86 const OutputRelocSection& getRelDyn() const; 87 88 OutputRelocSection& getRelPLT(); 89 const OutputRelocSection& getRelPLT() const; 90 getGOTSymbol()91 LDSymbol* getGOTSymbol() { return m_pGOTSymbol; } getGOTSymbol()92 const LDSymbol* getGOTSymbol() const { return m_pGOTSymbol; } 93 94 /// getTargetSectionOrder - compute the layout order of X86 target sections 95 unsigned int getTargetSectionOrder(const LDSection& pSectHdr) const; 96 97 /// finalizeTargetSymbols - finalize the symbol value 98 bool finalizeTargetSymbols(); 99 100 /// getPointerRel - get pointer relocation type. getPointerRel()101 Relocation::Type getPointerRel() 102 { return m_PointerRel; } 103 getCopyRelType()104 Relocation::Type getCopyRelType() const { return m_CopyRel; } getPointerRelType()105 Relocation::Type getPointerRelType() const { return m_PointerRel; } 106 107 protected: 108 void defineGOTSymbol(IRBuilder& pBuilder, Fragment&); 109 110 /// getRelEntrySize - the size in BYTE of rel type relocation getRelEntrySize()111 size_t getRelEntrySize() 112 { return m_RelEntrySize; } 113 114 /// getRelEntrySize - the size in BYTE of rela type relocation getRelaEntrySize()115 size_t getRelaEntrySize() 116 { return m_RelaEntrySize; } 117 118 private: 119 /// doCreateProgramHdrs - backend can implement this function to create the 120 /// target-dependent segments 121 void doCreateProgramHdrs(Module& pModule); 122 123 virtual void setGOTSectionSize(IRBuilder& pBuilder) = 0; 124 125 virtual uint64_t emitGOTSectionData(MemoryRegion& pRegion) const = 0; 126 127 virtual uint64_t emitGOTPLTSectionData(MemoryRegion& pRegion, 128 const ELFFileFormat* FileFormat) const = 0; 129 130 virtual void setRelDynSize() = 0; 131 virtual void setRelPLTSize() = 0; 132 133 protected: 134 Relocator* m_pRelocator; 135 X86PLT* m_pPLT; 136 /// m_RelDyn - dynamic relocation table of .rel.dyn 137 OutputRelocSection* m_pRelDyn; 138 /// m_RelPLT - dynamic relocation table of .rel.plt 139 OutputRelocSection* m_pRelPLT; 140 141 X86ELFDynamic* m_pDynamic; 142 LDSymbol* m_pGOTSymbol; 143 144 size_t m_RelEntrySize; 145 size_t m_RelaEntrySize; 146 147 Relocation::Type m_CopyRel; 148 Relocation::Type m_PointerRel; 149 }; 150 151 // 152 //===----------------------------------------------------------------------===// 153 /// X86_32GNULDBackend - linker backend of X86-32 target of GNU ELF format 154 /// 155 class X86_32GNULDBackend : public X86GNULDBackend 156 { 157 public: 158 X86_32GNULDBackend(const LinkerConfig& pConfig, GNUInfo* pInfo); 159 160 ~X86_32GNULDBackend(); 161 162 void initTargetSections(Module& pModule, ObjectBuilder& pBuilder); 163 164 X86_32GOT& getGOT(); 165 166 const X86_32GOT& getGOT() const; 167 168 X86_32GOTPLT& getGOTPLT(); 169 170 const X86_32GOTPLT& getGOTPLT() const; 171 172 private: 173 /// initRelocator - create and initialize Relocator. 174 bool initRelocator(); 175 176 void setGOTSectionSize(IRBuilder& pBuilder); 177 178 uint64_t emitGOTSectionData(MemoryRegion& pRegion) const; 179 180 uint64_t emitGOTPLTSectionData(MemoryRegion& pRegion, 181 const ELFFileFormat* FileFormat) const; 182 183 void setRelDynSize(); 184 void setRelPLTSize(); 185 186 private: 187 X86_32GOT* m_pGOT; 188 X86_32GOTPLT* m_pGOTPLT; 189 }; 190 191 // 192 //===----------------------------------------------------------------------===// 193 /// X86_64GNULDBackend - linker backend of X86-64 target of GNU ELF format 194 /// 195 class X86_64GNULDBackend : public X86GNULDBackend 196 { 197 public: 198 X86_64GNULDBackend(const LinkerConfig& pConfig, GNUInfo* pInfo); 199 200 ~X86_64GNULDBackend(); 201 202 void initTargetSections(Module& pModule, ObjectBuilder& pBuilder); 203 204 X86_64GOT& getGOT(); 205 206 const X86_64GOT& getGOT() const; 207 208 X86_64GOTPLT& getGOTPLT(); 209 210 const X86_64GOTPLT& getGOTPLT() const; 211 212 private: 213 /// initRelocator - create and initialize Relocator. 214 bool initRelocator(); 215 216 void setGOTSectionSize(IRBuilder& pBuilder); 217 218 uint64_t emitGOTSectionData(MemoryRegion& pRegion) const; 219 220 uint64_t emitGOTPLTSectionData(MemoryRegion& pRegion, 221 const ELFFileFormat* FileFormat) const; 222 223 void setRelDynSize(); 224 void setRelPLTSize(); 225 226 private: 227 X86_64GOT* m_pGOT; 228 X86_64GOTPLT* m_pGOTPLT; 229 }; 230 } // namespace of mcld 231 232 #endif 233 234