1 //===-- RuntimeDyldCOFF.cpp - Run-time dynamic linker for MC-JIT -*- C++ -*-==//
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 // Implementation of COFF support for the MC-JIT runtime dynamic linker.
10 //
11 //===----------------------------------------------------------------------===//
12
13 #include "RuntimeDyldCOFF.h"
14 #include "Targets/RuntimeDyldCOFFAArch64.h"
15 #include "Targets/RuntimeDyldCOFFI386.h"
16 #include "Targets/RuntimeDyldCOFFThumb.h"
17 #include "Targets/RuntimeDyldCOFFX86_64.h"
18 #include "llvm/ADT/STLExtras.h"
19 #include "llvm/ADT/Triple.h"
20 #include "llvm/Object/ObjectFile.h"
21 #include "llvm/Support/FormatVariadic.h"
22
23 using namespace llvm;
24 using namespace llvm::object;
25
26 #define DEBUG_TYPE "dyld"
27
28 namespace {
29
30 class LoadedCOFFObjectInfo final
31 : public LoadedObjectInfoHelper<LoadedCOFFObjectInfo,
32 RuntimeDyld::LoadedObjectInfo> {
33 public:
LoadedCOFFObjectInfo(RuntimeDyldImpl & RTDyld,RuntimeDyld::LoadedObjectInfo::ObjSectionToIDMap ObjSecToIDMap)34 LoadedCOFFObjectInfo(
35 RuntimeDyldImpl &RTDyld,
36 RuntimeDyld::LoadedObjectInfo::ObjSectionToIDMap ObjSecToIDMap)
37 : LoadedObjectInfoHelper(RTDyld, std::move(ObjSecToIDMap)) {}
38
39 OwningBinary<ObjectFile>
getObjectForDebug(const ObjectFile & Obj) const40 getObjectForDebug(const ObjectFile &Obj) const override {
41 return OwningBinary<ObjectFile>();
42 }
43 };
44 }
45
46 namespace llvm {
47
48 std::unique_ptr<RuntimeDyldCOFF>
create(Triple::ArchType Arch,RuntimeDyld::MemoryManager & MemMgr,JITSymbolResolver & Resolver)49 llvm::RuntimeDyldCOFF::create(Triple::ArchType Arch,
50 RuntimeDyld::MemoryManager &MemMgr,
51 JITSymbolResolver &Resolver) {
52 switch (Arch) {
53 default: llvm_unreachable("Unsupported target for RuntimeDyldCOFF.");
54 case Triple::x86:
55 return std::make_unique<RuntimeDyldCOFFI386>(MemMgr, Resolver);
56 case Triple::thumb:
57 return std::make_unique<RuntimeDyldCOFFThumb>(MemMgr, Resolver);
58 case Triple::x86_64:
59 return std::make_unique<RuntimeDyldCOFFX86_64>(MemMgr, Resolver);
60 case Triple::aarch64:
61 return std::make_unique<RuntimeDyldCOFFAArch64>(MemMgr, Resolver);
62 }
63 }
64
65 std::unique_ptr<RuntimeDyld::LoadedObjectInfo>
loadObject(const object::ObjectFile & O)66 RuntimeDyldCOFF::loadObject(const object::ObjectFile &O) {
67 if (auto ObjSectionToIDOrErr = loadObjectImpl(O)) {
68 return std::make_unique<LoadedCOFFObjectInfo>(*this, *ObjSectionToIDOrErr);
69 } else {
70 HasError = true;
71 raw_string_ostream ErrStream(ErrorStr);
72 logAllUnhandledErrors(ObjSectionToIDOrErr.takeError(), ErrStream);
73 return nullptr;
74 }
75 }
76
getSymbolOffset(const SymbolRef & Sym)77 uint64_t RuntimeDyldCOFF::getSymbolOffset(const SymbolRef &Sym) {
78 // The value in a relocatable COFF object is the offset.
79 return cantFail(Sym.getValue());
80 }
81
getDLLImportOffset(unsigned SectionID,StubMap & Stubs,StringRef Name,bool SetSectionIDMinus1)82 uint64_t RuntimeDyldCOFF::getDLLImportOffset(unsigned SectionID, StubMap &Stubs,
83 StringRef Name,
84 bool SetSectionIDMinus1) {
85 LLVM_DEBUG(dbgs() << "Getting DLLImport entry for " << Name << "... ");
86 assert(Name.startswith(getImportSymbolPrefix()) && "Not a DLLImport symbol?");
87 RelocationValueRef Reloc;
88 Reloc.SymbolName = Name.data();
89 auto I = Stubs.find(Reloc);
90 if (I != Stubs.end()) {
91 LLVM_DEBUG(dbgs() << format("{0:x8}", I->second) << "\n");
92 return I->second;
93 }
94
95 assert(SectionID < Sections.size() && "SectionID out of range");
96 auto &Sec = Sections[SectionID];
97 auto EntryOffset = alignTo(Sec.getStubOffset(), PointerSize);
98 Sec.advanceStubOffset(EntryOffset + PointerSize - Sec.getStubOffset());
99 Stubs[Reloc] = EntryOffset;
100
101 RelocationEntry RE(SectionID, EntryOffset, PointerReloc, 0, false,
102 Log2_64(PointerSize));
103 // Hack to tell I386/Thumb resolveRelocation that this isn't section relative.
104 if (SetSectionIDMinus1)
105 RE.Sections.SectionA = -1;
106 addRelocationForSymbol(RE, Name.drop_front(getImportSymbolPrefix().size()));
107
108 LLVM_DEBUG({
109 dbgs() << "Creating entry at "
110 << formatv("{0:x16} + {1:x8} ( {2:x16} )", Sec.getLoadAddress(),
111 EntryOffset, Sec.getLoadAddress() + EntryOffset)
112 << "\n";
113 });
114 return EntryOffset;
115 }
116
isCompatibleFile(const object::ObjectFile & Obj) const117 bool RuntimeDyldCOFF::isCompatibleFile(const object::ObjectFile &Obj) const {
118 return Obj.isCOFF();
119 }
120
121 } // namespace llvm
122