AArch64GOT.h revision 551ae4ebd3e9d137ea668fb83ae4a55b8cfba451 
1//===- AArch64GOT.h -------------------------------------------------------===//
2//
3//                     The MCLinker Project
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9#ifndef TARGET_AARCH64_AARCH64GOT_H
10#define TARGET_AARCH64_AARCH64GOT_H
11#ifdef ENABLE_UNITTEST
12#include <gtest.h>
13#endif
14
15#include <mcld/Support/MemoryRegion.h>
16#include <mcld/Target/GOT.h>
17
18#include <llvm/ADT/DenseMap.h>
19
20#include <vector>
21
22namespace mcld {
23
24class LDSection;
25
26/** \class AArch64GOTEntry
27 *  \brief GOT Entry with size of 8 bytes
28 */
29class AArch64GOTEntry : public GOT::Entry<8>
30{
31public:
32  AArch64GOTEntry(uint64_t pContent, SectionData* pParent)
33   : GOT::Entry<8>(pContent, pParent)
34  {}
35};
36
37/** \class AArch64GOT
38 *  \brief AArch64 Global Offset Table.
39 *
40 *  AArch64 GOT integrates traditional .got.plt and .got sections into one.
41 *  Traditional .got.plt is placed in the front part of GOT (PLTGOT), and
42 *  traditional .got is placed in the rear part of GOT (GOT). When -z now and
43 *  -z relro are given, the got section layout will be as below. Otherwise,
44 *  there will be two seperated sections, .got and .got.plt.
45 *
46 *  This class may be used as .got (with no GOTPLT entry), .got.plt (with only
47 *  GOTPLT entries) or .got (with GOTPLT and normal GOT entries)
48 *
49 *  AArch64 .got
50 *            +--------------+
51 *            |    GOT0      |
52 *            +--------------+
53 *            |    GOTPLT    |
54 *            +--------------+
55 *            |    GOT       |
56 *            +--------------+
57 *
58 */
59class AArch64GOT : public GOT
60{
61public:
62  AArch64GOT(LDSection &pSection);
63
64  ~AArch64GOT();
65
66  /// createGOT0 - create the defualt GOT0 entries. This function called when
67  /// it's a .got section (with GOTPLT entries and normal GOT entry) or it's a
68  /// .got.plt section
69  void createGOT0();
70
71  AArch64GOTEntry* createGOT();
72  AArch64GOTEntry* createGOTPLT();
73
74  void finalizeSectionSize();
75
76  uint64_t emit(MemoryRegion& pRegion);
77
78  void applyGOT0(uint64_t pAddress);
79
80  void applyGOTPLT(uint64_t pPLTBase);
81
82  bool hasGOT1() const;
83
84private:
85  typedef std::vector<AArch64GOTEntry*> EntryListType;
86  typedef EntryListType::iterator entry_iterator;
87  typedef EntryListType::const_iterator const_entry_iterator;
88
89private:
90  AArch64GOTEntry* m_pGOTPLTFront;
91  AArch64GOTEntry* m_pGOTFront;
92
93  /// m_GOTPLTEntries - a list of gotplt entries
94  EntryListType m_GOTPLT;
95
96  /// m_GOTEntris - a list of got entries
97  EntryListType m_GOT;
98};
99
100} // namespace of mcld
101
102#endif
103
104