EhFrame.h revision affc150dc44fab1911775a49636d0ce85333b634 
1//===- EhFrame.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 MCLD_EXCEPTION_HANDLING_FRAME_H
10#define MCLD_EXCEPTION_HANDLING_FRAME_H
11#ifdef ENABLE_UNITTEST
12#include <gtest.h>
13#endif
14#include <vector>
15
16#include <mcld/ADT/TypeTraits.h>
17#include <mcld/LD/CIE.h>
18#include <mcld/LD/FDE.h>
19#include <mcld/MC/MCRegionFragment.h>
20#include <mcld/Support/GCFactory.h>
21
22namespace mcld
23{
24/** \class EhFrame
25 *  \brief EhFrame represents .eh_frame section
26 *  EhFrame is responsible to parse the input eh_frame sections and create
27 *  the corresponding CIE and FDE entries.
28 */
29
30class TargetLDBackend;
31
32class EhFrame
33{
34public:
35  typedef ConstTraits<unsigned char>::pointer ConstAddress;
36  typedef std::vector<CIE*> CIEListType;
37  typedef std::vector<FDE*> FDEListType;
38  typedef CIEListType::iterator cie_iterator;
39  typedef CIEListType::const_iterator const_cie_iterator;
40  typedef FDEListType::iterator fde_iterator;
41  typedef FDEListType::const_iterator const_fde_iterator;
42
43public:
44  EhFrame();
45  ~EhFrame();
46
47  /// readEhFrame - read an .eh_frame section and create the corresponding
48  /// CIEs and FDEs
49  /// @param pSD - the MCSectionData of this input eh_frame
50  /// @param pSection - the input eh_frame
51  /// @param pArea - the memory area which pSection is within.
52  /// @ return - size of this eh_frame section, 0 if we do not recognize
53  /// this eh_frame or this is an empty section
54  uint64_t readEhFrame(Layout& pLayout,
55                       const TargetLDBackend& pBackend,
56                       llvm::MCSectionData& pSD,
57                       LDSection& pSection,
58                       MemoryArea& pArea);
59
60  // ----- observers ----- //
61  cie_iterator cie_begin()
62  { return m_CIEs.begin(); }
63
64  const_cie_iterator cie_begin() const
65  { return m_CIEs.begin(); }
66
67  cie_iterator cie_end()
68  { return m_CIEs.end(); }
69
70  const_cie_iterator cie_end() const
71  { return m_CIEs.end(); }
72
73  fde_iterator fde_begin()
74  { return m_FDEs.begin(); }
75
76  const_fde_iterator fde_begin() const
77  { return m_FDEs.begin(); }
78
79  fde_iterator fde_end()
80  { return m_FDEs.end(); }
81
82  const_fde_iterator fde_end() const
83  { return m_FDEs.end(); }
84
85  /// getFDECount - the number of FDE entries
86  size_t getFDECount()
87  { return m_FDEs.size(); }
88
89  size_t getFDECount() const
90  { return m_FDEs.size(); }
91
92  /// canRecognizeAllEhFrame - return if we are able to parse all input
93  /// eh_frame sections
94  /// @return false - if there is any input .eh_frame section that
95  /// we are not able to recognize
96  bool canRecognizeAllEhFrame()
97  { return m_fCanRecognizeAll; }
98
99  bool canRecognizeAllEhFrame() const
100  { return m_fCanRecognizeAll; }
101
102private:
103  typedef std::vector<llvm::MCFragment*> FragListType;
104
105private:
106  /// addCIE - parse and create a CIE entry
107  /// @return false - cannot recognize this CIE
108  bool addCIE(MemoryRegion& pFrag,
109              const TargetLDBackend& pBackend,
110              FragListType& pFragList);
111
112  /// addFDE - parse and create an FDE entry
113  /// @return false - cannot recognize this FDE
114  bool addFDE(MemoryRegion& pFrag,
115              const TargetLDBackend& pBackend,
116              FragListType& pFragList);
117
118  /// readVal - read a 32 bit data from pAddr, swap it if needed
119  uint32_t readVal(ConstAddress pAddr, bool pIsTargetLittleEndian);
120
121  /// skipLEB128 - skip the first LEB128 encoded value from *pp, update *pp
122  /// to the next character.
123  /// @return - false if we ran off the end of the string.
124  /// @ref - GNU gold 1.11, ehframe.h, Eh_frame::skip_leb128.
125  bool skipLEB128(ConstAddress* pp, ConstAddress pend);
126
127  /// deleteFragments - release the MemoryRegion and delete MCFragments in pList
128  void deleteFragments(FragListType& pList, MemoryArea& pArea);
129
130private:
131  CIEListType m_CIEs;
132  FDEListType m_FDEs;
133
134  bool m_fCanRecognizeAll;
135};
136
137} // namespace of mcld
138
139#endif
140
141