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 24 class RuntimeDyldELF : public RuntimeDyldImpl { 25 26 void resolveRelocation(const SectionEntry &Section, uint64_t Offset, 27 uint64_t Value, uint32_t Type, int64_t Addend, 28 uint64_t SymOffset = 0, SID SectionID = 0); 29 30 void resolveX86_64Relocation(const SectionEntry &Section, uint64_t Offset, 31 uint64_t Value, uint32_t Type, int64_t Addend, 32 uint64_t SymOffset); 33 34 void resolveX86Relocation(const SectionEntry &Section, uint64_t Offset, 35 uint32_t Value, uint32_t Type, int32_t Addend); 36 37 void resolveAArch64Relocation(const SectionEntry &Section, uint64_t Offset, 38 uint64_t Value, uint32_t Type, int64_t Addend); 39 40 void resolveARMRelocation(const SectionEntry &Section, uint64_t Offset, 41 uint32_t Value, uint32_t Type, int32_t Addend); 42 43 void resolveMIPSRelocation(const SectionEntry &Section, uint64_t Offset, 44 uint32_t Value, uint32_t Type, int32_t Addend); 45 46 void resolvePPC32Relocation(const SectionEntry &Section, uint64_t Offset, 47 uint64_t Value, uint32_t Type, int64_t Addend); 48 49 void resolvePPC64Relocation(const SectionEntry &Section, uint64_t Offset, 50 uint64_t Value, uint32_t Type, int64_t Addend); 51 52 void resolveSystemZRelocation(const SectionEntry &Section, uint64_t Offset, 53 uint64_t Value, uint32_t Type, int64_t Addend); 54 55 void resolveMIPS64Relocation(const SectionEntry &Section, uint64_t Offset, 56 uint64_t Value, uint32_t Type, int64_t Addend, 57 uint64_t SymOffset, SID SectionID); 58 59 int64_t evaluateMIPS64Relocation(const SectionEntry &Section, 60 uint64_t Offset, uint64_t Value, 61 uint32_t Type, int64_t Addend, 62 uint64_t SymOffset, SID SectionID); 63 64 void applyMIPS64Relocation(uint8_t *TargetPtr, int64_t CalculatedValue, 65 uint32_t Type); 66 67 unsigned getMaxStubSize() override { 68 if (Arch == Triple::aarch64 || Arch == Triple::aarch64_be) 69 return 20; // movz; movk; movk; movk; br 70 if (Arch == Triple::arm || Arch == Triple::thumb) 71 return 8; // 32-bit instruction and 32-bit address 72 else if (IsMipsO32ABI) 73 return 16; 74 else if (Arch == Triple::ppc64 || Arch == Triple::ppc64le) 75 return 44; 76 else if (Arch == Triple::x86_64) 77 return 6; // 2-byte jmp instruction + 32-bit relative address 78 else if (Arch == Triple::systemz) 79 return 16; 80 else 81 return 0; 82 } 83 84 unsigned getStubAlignment() override { 85 if (Arch == Triple::systemz) 86 return 8; 87 else 88 return 1; 89 } 90 91 void setMipsABI(const ObjectFile &Obj) override; 92 93 void findPPC64TOCSection(const ELFObjectFileBase &Obj, 94 ObjSectionToIDMap &LocalSections, 95 RelocationValueRef &Rel); 96 void findOPDEntrySection(const ELFObjectFileBase &Obj, 97 ObjSectionToIDMap &LocalSections, 98 RelocationValueRef &Rel); 99 100 size_t getGOTEntrySize(); 101 102 SectionEntry &getSection(unsigned SectionID) { return Sections[SectionID]; } 103 104 // Allocate no GOT entries for use in the given section. 105 uint64_t allocateGOTEntries(unsigned SectionID, unsigned no); 106 107 // Resolve the relvative address of GOTOffset in Section ID and place 108 // it at the given Offset 109 void resolveGOTOffsetRelocation(unsigned SectionID, uint64_t Offset, 110 uint64_t GOTOffset); 111 112 // For a GOT entry referenced from SectionID, compute a relocation entry 113 // that will place the final resolved value in the GOT slot 114 RelocationEntry computeGOTOffsetRE(unsigned SectionID, 115 uint64_t GOTOffset, 116 uint64_t SymbolOffset, 117 unsigned Type); 118 119 // Compute the address in memory where we can find the placeholder 120 void *computePlaceholderAddress(unsigned SectionID, uint64_t Offset) const; 121 122 // Split out common case for createing the RelocationEntry for when the relocation requires 123 // no particular advanced processing. 124 void processSimpleRelocation(unsigned SectionID, uint64_t Offset, unsigned RelType, RelocationValueRef Value); 125 126 // Return matching *LO16 relocation (Mips specific) 127 uint32_t getMatchingLoRelocation(uint32_t RelType, 128 bool IsLocal = false) const; 129 130 // The tentative ID for the GOT section 131 unsigned GOTSectionID; 132 133 // Records the current number of allocated slots in the GOT 134 // (This would be equivalent to GOTEntries.size() were it not for relocations 135 // that consume more than one slot) 136 unsigned CurrentGOTIndex; 137 138 // A map from section to a GOT section that has entries for section's GOT 139 // relocations. (Mips64 specific) 140 DenseMap<SID, SID> SectionToGOTMap; 141 142 // A map to avoid duplicate got entries (Mips64 specific) 143 StringMap<uint64_t> GOTSymbolOffsets; 144 145 // *HI16 relocations will be added for resolving when we find matching 146 // *LO16 part. (Mips specific) 147 SmallVector<std::pair<RelocationValueRef, RelocationEntry>, 8> PendingRelocs; 148 149 // When a module is loaded we save the SectionID of the EH frame section 150 // in a table until we receive a request to register all unregistered 151 // EH frame sections with the memory manager. 152 SmallVector<SID, 2> UnregisteredEHFrameSections; 153 SmallVector<SID, 2> RegisteredEHFrameSections; 154 155 bool relocationNeedsStub(const RelocationRef &R) const override; 156 157 public: 158 RuntimeDyldELF(RuntimeDyld::MemoryManager &MemMgr, 159 RuntimeDyld::SymbolResolver &Resolver); 160 ~RuntimeDyldELF() override; 161 162 std::unique_ptr<RuntimeDyld::LoadedObjectInfo> 163 loadObject(const object::ObjectFile &O) override; 164 165 void resolveRelocation(const RelocationEntry &RE, uint64_t Value) override; 166 relocation_iterator 167 processRelocationRef(unsigned SectionID, relocation_iterator RelI, 168 const ObjectFile &Obj, 169 ObjSectionToIDMap &ObjSectionToID, 170 StubMap &Stubs) override; 171 bool isCompatibleFile(const object::ObjectFile &Obj) const override; 172 void registerEHFrames() override; 173 void deregisterEHFrames() override; 174 void finalizeLoad(const ObjectFile &Obj, 175 ObjSectionToIDMap &SectionMap) override; 176 }; 177 178 } // end namespace llvm 179 180 #endif 181
