1//===-- RuntimeDyldMachO.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// MachO support for MC-JIT runtime dynamic linker.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_RUNTIME_DYLD_MACHO_H
15#define LLVM_RUNTIME_DYLD_MACHO_H
16
17#include "ObjectImageCommon.h"
18#include "RuntimeDyldImpl.h"
19#include "llvm/ADT/IndexedMap.h"
20#include "llvm/Object/MachO.h"
21#include "llvm/Support/Format.h"
22
23using namespace llvm;
24using namespace llvm::object;
25
26namespace llvm {
27class RuntimeDyldMachO : public RuntimeDyldImpl {
28private:
29
30  /// Write the least significant 'Size' bytes in 'Value' out at the address
31  /// pointed to by Addr.
32  bool applyRelocationValue(uint8_t *Addr, uint64_t Value, unsigned Size) {
33    for (unsigned i = 0; i < Size; ++i) {
34      *Addr++ = (uint8_t)Value;
35      Value >>= 8;
36    }
37
38    return false;
39  }
40
41  bool resolveI386Relocation(const RelocationEntry &RE, uint64_t Value);
42  bool resolveX86_64Relocation(const RelocationEntry &RE, uint64_t Value);
43  bool resolveARMRelocation(const RelocationEntry &RE, uint64_t Value);
44  bool resolveAArch64Relocation(const RelocationEntry &RE, uint64_t Value);
45
46  // Populate stubs in __jump_table section.
47  void populateJumpTable(MachOObjectFile &Obj, const SectionRef &JTSection,
48                         unsigned JTSectionID);
49
50  // Populate __pointers section.
51  void populatePointersSection(MachOObjectFile &Obj, const SectionRef &PTSection,
52                               unsigned PTSectionID);
53
54  unsigned getMaxStubSize() override {
55    if (Arch == Triple::arm || Arch == Triple::thumb)
56      return 8; // 32-bit instruction and 32-bit address
57    else if (Arch == Triple::x86_64)
58      return 8; // GOT entry
59    else
60      return 0;
61  }
62
63  unsigned getStubAlignment() override { return 1; }
64
65  relocation_iterator processSECTDIFFRelocation(
66                                             unsigned SectionID,
67                                             relocation_iterator RelI,
68                                             ObjectImage &ObjImg,
69                                             ObjSectionToIDMap &ObjSectionToID);
70
71  relocation_iterator processI386ScatteredVANILLA(
72					     unsigned SectionID,
73					     relocation_iterator RelI,
74					     ObjectImage &ObjImg,
75					     ObjSectionToIDMap &ObjSectionToID);
76
77  struct EHFrameRelatedSections {
78    EHFrameRelatedSections()
79        : EHFrameSID(RTDYLD_INVALID_SECTION_ID),
80          TextSID(RTDYLD_INVALID_SECTION_ID),
81          ExceptTabSID(RTDYLD_INVALID_SECTION_ID) {}
82    EHFrameRelatedSections(SID EH, SID T, SID Ex)
83        : EHFrameSID(EH), TextSID(T), ExceptTabSID(Ex) {}
84    SID EHFrameSID;
85    SID TextSID;
86    SID ExceptTabSID;
87  };
88
89  // When a module is loaded we save the SectionID of the EH frame section
90  // in a table until we receive a request to register all unregistered
91  // EH frame sections with the memory manager.
92  SmallVector<EHFrameRelatedSections, 2> UnregisteredEHFrameSections;
93
94public:
95  RuntimeDyldMachO(RTDyldMemoryManager *mm) : RuntimeDyldImpl(mm) {}
96
97  void resolveRelocation(const RelocationEntry &RE, uint64_t Value) override;
98  relocation_iterator
99  processRelocationRef(unsigned SectionID, relocation_iterator RelI,
100                       ObjectImage &Obj, ObjSectionToIDMap &ObjSectionToID,
101                       const SymbolTableMap &Symbols, StubMap &Stubs) override;
102  bool isCompatibleFormat(const ObjectBuffer *Buffer) const override;
103  bool isCompatibleFile(const object::ObjectFile *Obj) const override;
104  void registerEHFrames() override;
105  void finalizeLoad(ObjectImage &ObjImg,
106                    ObjSectionToIDMap &SectionMap) override;
107
108  static ObjectImage *createObjectImage(ObjectBuffer *Buffer);
109  static ObjectImage *
110  createObjectImageFromFile(std::unique_ptr<object::ObjectFile> InputObject);
111};
112
113} // end namespace llvm
114
115#endif
116