1 //===-------------- ELF.cpp - JIT linker function for ELF -------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // ELF jit-link function. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #include "llvm/ExecutionEngine/JITLink/ELF.h" 14 15 #include "llvm/BinaryFormat/ELF.h" 16 #include "llvm/ExecutionEngine/JITLink/ELF_aarch64.h" 17 #include "llvm/ExecutionEngine/JITLink/ELF_riscv.h" 18 #include "llvm/ExecutionEngine/JITLink/ELF_x86_64.h" 19 #include "llvm/Object/ELF.h" 20 #include "llvm/Support/Endian.h" 21 #include "llvm/Support/Format.h" 22 #include "llvm/Support/MemoryBuffer.h" 23 #include <cstring> 24 25 using namespace llvm; 26 27 #define DEBUG_TYPE "jitlink" 28 29 namespace llvm { 30 namespace jitlink { 31 32 Expected<uint16_t> readTargetMachineArch(StringRef Buffer) { 33 const char *Data = Buffer.data(); 34 35 if (Data[ELF::EI_DATA] == ELF::ELFDATA2LSB) { 36 if (Data[ELF::EI_CLASS] == ELF::ELFCLASS64) { 37 if (auto File = llvm::object::ELF64LEFile::create(Buffer)) { 38 return File->getHeader().e_machine; 39 } else { 40 return File.takeError(); 41 } 42 } else if (Data[ELF::EI_CLASS] == ELF::ELFCLASS32) { 43 if (auto File = llvm::object::ELF32LEFile::create(Buffer)) { 44 return File->getHeader().e_machine; 45 } else { 46 return File.takeError(); 47 } 48 } 49 } 50 51 return ELF::EM_NONE; 52 } 53 54 Expected<std::unique_ptr<LinkGraph>> 55 createLinkGraphFromELFObject(MemoryBufferRef ObjectBuffer) { 56 StringRef Buffer = ObjectBuffer.getBuffer(); 57 if (Buffer.size() < ELF::EI_MAG3 + 1) 58 return make_error<JITLinkError>("Truncated ELF buffer"); 59 60 if (memcmp(Buffer.data(), ELF::ElfMagic, strlen(ELF::ElfMagic)) != 0) 61 return make_error<JITLinkError>("ELF magic not valid"); 62 63 Expected<uint16_t> TargetMachineArch = readTargetMachineArch(Buffer); 64 if (!TargetMachineArch) 65 return TargetMachineArch.takeError(); 66 67 switch (*TargetMachineArch) { 68 case ELF::EM_AARCH64: 69 return createLinkGraphFromELFObject_aarch64(ObjectBuffer); 70 case ELF::EM_RISCV: 71 return createLinkGraphFromELFObject_riscv(ObjectBuffer); 72 case ELF::EM_X86_64: 73 return createLinkGraphFromELFObject_x86_64(ObjectBuffer); 74 default: 75 return make_error<JITLinkError>( 76 "Unsupported target machine architecture in ELF object " + 77 ObjectBuffer.getBufferIdentifier()); 78 } 79 } 80 81 void link_ELF(std::unique_ptr<LinkGraph> G, 82 std::unique_ptr<JITLinkContext> Ctx) { 83 switch (G->getTargetTriple().getArch()) { 84 case Triple::aarch64: 85 link_ELF_aarch64(std::move(G), std::move(Ctx)); 86 return; 87 case Triple::riscv32: 88 case Triple::riscv64: 89 link_ELF_riscv(std::move(G), std::move(Ctx)); 90 return; 91 case Triple::x86_64: 92 link_ELF_x86_64(std::move(G), std::move(Ctx)); 93 return; 94 default: 95 Ctx->notifyFailed(make_error<JITLinkError>( 96 "Unsupported target machine architecture in ELF link graph " + 97 G->getName())); 98 return; 99 } 100 } 101 102 } // end namespace jitlink 103 } // end namespace llvm 104