1 //===-- RuntimeDyldELF.h - Run-time dynamic linker for MC-JIT ---*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // ELF support for MC-JIT runtime dynamic linker. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #ifndef LLVM_LIB_EXECUTIONENGINE_RUNTIMEDYLD_RUNTIMEDYLDELF_H 15 #define LLVM_LIB_EXECUTIONENGINE_RUNTIMEDYLD_RUNTIMEDYLDELF_H 16 17 #include "RuntimeDyldImpl.h" 18 #include "llvm/ADT/DenseMap.h" 19 20 using namespace llvm; 21 22 namespace llvm { 23 namespace object { 24 class ELFObjectFileBase; 25 } 26 27 class RuntimeDyldELF : public RuntimeDyldImpl { 28 29 void resolveRelocation(const SectionEntry &Section, uint64_t Offset, 30 uint64_t Value, uint32_t Type, int64_t Addend, 31 uint64_t SymOffset = 0, SID SectionID = 0); 32 33 void resolveX86_64Relocation(const SectionEntry &Section, uint64_t Offset, 34 uint64_t Value, uint32_t Type, int64_t Addend, 35 uint64_t SymOffset); 36 37 void resolveX86Relocation(const SectionEntry &Section, uint64_t Offset, 38 uint32_t Value, uint32_t Type, int32_t Addend); 39 40 void resolveAArch64Relocation(const SectionEntry &Section, uint64_t Offset, 41 uint64_t Value, uint32_t Type, int64_t Addend); 42 43 void resolveARMRelocation(const SectionEntry &Section, uint64_t Offset, 44 uint32_t Value, uint32_t Type, int32_t Addend); 45 46 void resolveMIPSRelocation(const SectionEntry &Section, uint64_t Offset, 47 uint32_t Value, uint32_t Type, int32_t Addend); 48 49 void resolvePPC32Relocation(const SectionEntry &Section, uint64_t Offset, 50 uint64_t Value, uint32_t Type, int64_t Addend); 51 52 void resolvePPC64Relocation(const SectionEntry &Section, uint64_t Offset, 53 uint64_t Value, uint32_t Type, int64_t Addend); 54 55 void resolveSystemZRelocation(const SectionEntry &Section, uint64_t Offset, 56 uint64_t Value, uint32_t Type, int64_t Addend); 57 58 void resolveMIPSN32Relocation(const SectionEntry &Section, uint64_t Offset, 59 uint64_t Value, uint32_t Type, int64_t Addend, 60 uint64_t SymOffset, SID SectionID); 61 void resolveMIPSN64Relocation(const SectionEntry &Section, uint64_t Offset, 62 uint64_t Value, uint32_t Type, int64_t Addend, 63 uint64_t SymOffset, SID SectionID); 64 65 int64_t evaluateMIPS32Relocation(const SectionEntry &Section, uint64_t Offset, 66 uint64_t Value, uint32_t Type); 67 int64_t evaluateMIPS64Relocation(const SectionEntry &Section, 68 uint64_t Offset, uint64_t Value, 69 uint32_t Type, int64_t Addend, 70 uint64_t SymOffset, SID SectionID); 71 72 void applyMIPSRelocation(uint8_t *TargetPtr, int64_t CalculatedValue, 73 uint32_t Type); 74 75 unsigned getMaxStubSize() override { 76 if (Arch == Triple::aarch64 || Arch == Triple::aarch64_be) 77 return 20; // movz; movk; movk; movk; br 78 if (Arch == Triple::arm || Arch == Triple::thumb) 79 return 8; // 32-bit instruction and 32-bit address 80 else if (IsMipsO32ABI) 81 return 16; 82 else if (Arch == Triple::ppc64 || Arch == Triple::ppc64le) 83 return 44; 84 else if (Arch == Triple::x86_64) 85 return 6; // 2-byte jmp instruction + 32-bit relative address 86 else if (Arch == Triple::systemz) 87 return 16; 88 else 89 return 0; 90 } 91 92 unsigned getStubAlignment() override { 93 if (Arch == Triple::systemz) 94 return 8; 95 else 96 return 1; 97 } 98 99 void setMipsABI(const ObjectFile &Obj) override; 100 101 Error findPPC64TOCSection(const ELFObjectFileBase &Obj, 102 ObjSectionToIDMap &LocalSections, 103 RelocationValueRef &Rel); 104 Error findOPDEntrySection(const ELFObjectFileBase &Obj, 105 ObjSectionToIDMap &LocalSections, 106 RelocationValueRef &Rel); 107 108 size_t getGOTEntrySize(); 109 110 SectionEntry &getSection(unsigned SectionID) { return Sections[SectionID]; } 111 112 // Allocate no GOT entries for use in the given section. 113 uint64_t allocateGOTEntries(unsigned SectionID, unsigned no); 114 115 // Resolve the relvative address of GOTOffset in Section ID and place 116 // it at the given Offset 117 void resolveGOTOffsetRelocation(unsigned SectionID, uint64_t Offset, 118 uint64_t GOTOffset); 119 120 // For a GOT entry referenced from SectionID, compute a relocation entry 121 // that will place the final resolved value in the GOT slot 122 RelocationEntry computeGOTOffsetRE(unsigned SectionID, 123 uint64_t GOTOffset, 124 uint64_t SymbolOffset, 125 unsigned Type); 126 127 // Compute the address in memory where we can find the placeholder 128 void *computePlaceholderAddress(unsigned SectionID, uint64_t Offset) const; 129 130 // Split out common case for createing the RelocationEntry for when the relocation requires 131 // no particular advanced processing. 132 void processSimpleRelocation(unsigned SectionID, uint64_t Offset, unsigned RelType, RelocationValueRef Value); 133 134 // Return matching *LO16 relocation (Mips specific) 135 uint32_t getMatchingLoRelocation(uint32_t RelType, 136 bool IsLocal = false) const; 137 138 // The tentative ID for the GOT section 139 unsigned GOTSectionID; 140 141 // Records the current number of allocated slots in the GOT 142 // (This would be equivalent to GOTEntries.size() were it not for relocations 143 // that consume more than one slot) 144 unsigned CurrentGOTIndex; 145 146 // A map from section to a GOT section that has entries for section's GOT 147 // relocations. (Mips64 specific) 148 DenseMap<SID, SID> SectionToGOTMap; 149 150 // A map to avoid duplicate got entries (Mips64 specific) 151 StringMap<uint64_t> GOTSymbolOffsets; 152 153 // *HI16 relocations will be added for resolving when we find matching 154 // *LO16 part. (Mips specific) 155 SmallVector<std::pair<RelocationValueRef, RelocationEntry>, 8> PendingRelocs; 156 157 // When a module is loaded we save the SectionID of the EH frame section 158 // in a table until we receive a request to register all unregistered 159 // EH frame sections with the memory manager. 160 SmallVector<SID, 2> UnregisteredEHFrameSections; 161 SmallVector<SID, 2> RegisteredEHFrameSections; 162 163 bool relocationNeedsStub(const RelocationRef &R) const override; 164 165 public: 166 RuntimeDyldELF(RuntimeDyld::MemoryManager &MemMgr, 167 JITSymbolResolver &Resolver); 168 ~RuntimeDyldELF() override; 169 170 std::unique_ptr<RuntimeDyld::LoadedObjectInfo> 171 loadObject(const object::ObjectFile &O) override; 172 173 void resolveRelocation(const RelocationEntry &RE, uint64_t Value) override; 174 Expected<relocation_iterator> 175 processRelocationRef(unsigned SectionID, relocation_iterator RelI, 176 const ObjectFile &Obj, 177 ObjSectionToIDMap &ObjSectionToID, 178 StubMap &Stubs) override; 179 bool isCompatibleFile(const object::ObjectFile &Obj) const override; 180 void registerEHFrames() override; 181 void deregisterEHFrames() override; 182 Error finalizeLoad(const ObjectFile &Obj, 183 ObjSectionToIDMap &SectionMap) override; 184 }; 185 186 } // end namespace llvm 187 188 #endif 189