1 //===----- ELF_i386.cpp - JIT linker implementation for ELF/i386 ----===// 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/i386 jit-link implementation. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #include "llvm/ExecutionEngine/JITLink/ELF_i386.h" 14 #include "ELFLinkGraphBuilder.h" 15 #include "JITLinkGeneric.h" 16 #include "llvm/BinaryFormat/ELF.h" 17 #include "llvm/ExecutionEngine/JITLink/i386.h" 18 #include "llvm/Object/ELFObjectFile.h" 19 20 #define DEBUG_TYPE "jitlink" 21 22 using namespace llvm; 23 using namespace llvm::jitlink; 24 25 namespace llvm { 26 namespace jitlink { 27 28 class ELFJITLinker_i386 : public JITLinker<ELFJITLinker_i386> { 29 friend class JITLinker<ELFJITLinker_i386>; 30 31 public: 32 ELFJITLinker_i386(std::unique_ptr<JITLinkContext> Ctx, 33 std::unique_ptr<LinkGraph> G, PassConfiguration PassConfig) 34 : JITLinker(std::move(Ctx), std::move(G), std::move(PassConfig)) {} 35 36 private: 37 Error applyFixup(LinkGraph &G, Block &B, const Edge &E) const { 38 using namespace i386; 39 using namespace llvm::support; 40 41 switch (E.getKind()) { 42 case i386::None: { 43 break; 44 } 45 } 46 return Error::success(); 47 } 48 }; 49 50 template <typename ELFT> 51 class ELFLinkGraphBuilder_i386 : public ELFLinkGraphBuilder<ELFT> { 52 private: 53 static Expected<i386::EdgeKind_i386> getRelocationKind(const uint32_t Type) { 54 using namespace i386; 55 switch (Type) { 56 case ELF::R_386_NONE: 57 return EdgeKind_i386::None; 58 } 59 60 return make_error<JITLinkError>("Unsupported i386 relocation:" + 61 formatv("{0:d}", Type)); 62 } 63 64 Error addRelocations() override { 65 LLVM_DEBUG(dbgs() << "Adding relocations\n"); 66 using Base = ELFLinkGraphBuilder<ELFT>; 67 68 return Error::success(); 69 } 70 71 public: 72 ELFLinkGraphBuilder_i386(StringRef FileName, const object::ELFFile<ELFT> &Obj, 73 const Triple T) 74 : ELFLinkGraphBuilder<ELFT>(Obj, std::move(T), FileName, 75 i386::getEdgeKindName) {} 76 }; 77 78 Expected<std::unique_ptr<LinkGraph>> 79 createLinkGraphFromELFObject_i386(MemoryBufferRef ObjectBuffer) { 80 LLVM_DEBUG({ 81 dbgs() << "Building jitlink graph for new input " 82 << ObjectBuffer.getBufferIdentifier() << "...\n"; 83 }); 84 85 auto ELFObj = object::ObjectFile::createELFObjectFile(ObjectBuffer); 86 if (!ELFObj) 87 return ELFObj.takeError(); 88 89 assert((*ELFObj)->getArch() == Triple::x86 && 90 "Only i386 (little endian) is supported for now"); 91 92 auto &ELFObjFile = cast<object::ELFObjectFile<object::ELF32LE>>(**ELFObj); 93 return ELFLinkGraphBuilder_i386<object::ELF32LE>((*ELFObj)->getFileName(), 94 ELFObjFile.getELFFile(), 95 (*ELFObj)->makeTriple()) 96 .buildGraph(); 97 } 98 99 void link_ELF_i386(std::unique_ptr<LinkGraph> G, 100 std::unique_ptr<JITLinkContext> Ctx) { 101 PassConfiguration Config; 102 const Triple &TT = G->getTargetTriple(); 103 if (Ctx->shouldAddDefaultTargetPasses(TT)) { 104 if (auto MarkLive = Ctx->getMarkLivePass(TT)) 105 Config.PrePrunePasses.push_back(std::move(MarkLive)); 106 else 107 Config.PrePrunePasses.push_back(markAllSymbolsLive); 108 } 109 if (auto Err = Ctx->modifyPassConfig(*G, Config)) 110 return Ctx->notifyFailed(std::move(Err)); 111 112 ELFJITLinker_i386::link(std::move(Ctx), std::move(G), std::move(Config)); 113 } 114 115 } // namespace jitlink 116 } // namespace llvm