X86Relocator.h revision 87f34658dec9097d987d254a990ea7f311bfc95f 
1//===-  X86Relocator.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 X86_RELOCATION_FACTORY_H
10#define X86_RELOCATION_FACTORY_H
11#ifdef ENABLE_UNITTEST
12#include <gtest.h>
13#endif
14
15#include <mcld/LD/Relocator.h>
16#include <mcld/Target/GOT.h>
17#include <mcld/Target/PLT.h>
18#include <mcld/Target/KeyEntryMap.h>
19#include "X86LDBackend.h"
20
21namespace mcld {
22
23class ResolveInfo;
24class LinkerConfig;
25
26/** \class X86Relocator
27 *  \brief X86Relocator creates and destroys the X86 relocations.
28 *
29 */
30class X86Relocator : public Relocator
31{
32public:
33  typedef KeyEntryMap<ResolveInfo, PLTEntryBase> SymPLTMap;
34
35  /** \enum ReservedEntryType
36   *  \brief The reserved entry type of reserved space in ResolveInfo.
37   *
38   *  This is used for sacnRelocation to record what kinds of entries are
39   *  reserved for this resolved symbol. In X86, there are three kinds of
40   *  entries, GOT, PLT, and dynamic reloction.
41   *
42   *  bit:  3     2     1     0
43   *   |    | PLT | GOT | Rel |
44   *
45   *  value    Name         - Description
46   *
47   *  0000     None         - no reserved entry
48   *  0001     ReserveRel   - reserve an dynamic relocation entry
49   *  0010     ReserveGOT   - reserve an GOT entry
50   *  0100     ReservePLT   - reserve an PLT entry and the corresponding GOT,
51   *
52   */
53  enum ReservedEntryType {
54    None         = 0,
55    ReserveRel   = 1,
56    ReserveGOT   = 2,
57    ReservePLT   = 4,
58  };
59
60  /** \enum EntryValue
61   *  \brief The value of the entries. The symbol value will be decided at after
62   *  layout, so we mark the entry during scanRelocation and fill up the actual
63   *  value when applying relocations.
64   */
65  enum EntryValue {
66    Default = 0,
67    SymVal  = 1
68  };
69
70public:
71  X86Relocator(const LinkerConfig& pConfig);
72  ~X86Relocator();
73
74  virtual Result applyRelocation(Relocation& pRelocation) = 0;
75
76  virtual const char* getName(Relocation::Type pType) const = 0;
77
78  const SymPLTMap& getSymPLTMap() const { return m_SymPLTMap; }
79  SymPLTMap&       getSymPLTMap()       { return m_SymPLTMap; }
80
81  /// scanRelocation - determine the empty entries are needed or not and create
82  /// the empty entries if needed.
83  /// For X86, following entries are check to create:
84  /// - GOT entry (for .got and .got.plt sections)
85  /// - PLT entry (for .plt section)
86  /// - dynamin relocation entries (for .rel.plt and .rel.dyn sections)
87  void scanRelocation(Relocation& pReloc,
88                      IRBuilder& pBuilder,
89                      Module& pModule,
90                      LDSection& pSection,
91                      Input& pInput);
92
93protected:
94  /// addCopyReloc - add a copy relocation into .rel.dyn for pSym
95  /// @param pSym - A resolved copy symbol that defined in BSS section
96  void addCopyReloc(ResolveInfo& pSym, X86GNULDBackend& pTarget);
97
98  /// defineSymbolforCopyReloc - allocate a space in BSS section and
99  /// and force define the copy of pSym to BSS section
100  /// @return the output LDSymbol of the copy symbol
101  LDSymbol& defineSymbolforCopyReloc(IRBuilder& pLinker,
102                                     const ResolveInfo& pSym,
103                                     X86GNULDBackend& pTarget);
104
105private:
106  virtual void scanLocalReloc(Relocation& pReloc,
107                              IRBuilder& pBuilder,
108                              Module& pModule,
109                              LDSection& pSection) = 0;
110
111  virtual void scanGlobalReloc(Relocation& pReloc,
112                               IRBuilder& pBuilder,
113                               Module& pModule,
114                               LDSection& pSection) = 0;
115
116private:
117  SymPLTMap m_SymPLTMap;
118};
119
120/** \class X86_32Relocator
121 *  \brief X86_32Relocator creates and destroys the X86-32 relocations.
122 *
123 */
124class X86_32Relocator : public X86Relocator
125{
126public:
127  typedef KeyEntryMap<ResolveInfo, X86_32GOTEntry> SymGOTMap;
128  typedef KeyEntryMap<ResolveInfo, X86_32GOTEntry> SymGOTPLTMap;
129
130  enum {
131    R_386_TLS_OPT = 44 // mcld internal relocation type
132  };
133
134public:
135  X86_32Relocator(X86_32GNULDBackend& pParent, const LinkerConfig& pConfig);
136
137  Result applyRelocation(Relocation& pRelocation);
138
139  X86_32GNULDBackend& getTarget()
140  { return m_Target; }
141
142  const X86_32GNULDBackend& getTarget() const
143  { return m_Target; }
144
145  const char* getName(Relocation::Type pType) const;
146
147  Size getSize(Relocation::Type pType) const;
148
149  const SymGOTMap& getSymGOTMap() const { return m_SymGOTMap; }
150  SymGOTMap&       getSymGOTMap()       { return m_SymGOTMap; }
151
152  const SymGOTPLTMap& getSymGOTPLTMap() const { return m_SymGOTPLTMap; }
153  SymGOTPLTMap&       getSymGOTPLTMap()       { return m_SymGOTPLTMap; }
154
155  X86_32GOTEntry& getTLSModuleID();
156
157private:
158  void scanLocalReloc(Relocation& pReloc,
159                      IRBuilder& pBuilder,
160                      Module& pModule,
161                      LDSection& pSection);
162
163  void scanGlobalReloc(Relocation& pReloc,
164                       IRBuilder& pBuilder,
165                       Module& pModule,
166                       LDSection& pSection);
167
168  /// -----  tls optimization  ----- ///
169  /// convert R_386_TLS_IE to R_386_TLS_LE
170  void convertTLSIEtoLE(Relocation& pReloc, LDSection& pSection);
171
172private:
173  X86_32GNULDBackend& m_Target;
174  SymGOTMap m_SymGOTMap;
175  SymGOTPLTMap m_SymGOTPLTMap;
176};
177
178/** \class X86_64Relocator
179 *  \brief X86_64Relocator creates and destroys the X86-64 relocations.
180 *
181 */
182class X86_64Relocator : public X86Relocator
183{
184public:
185  typedef KeyEntryMap<ResolveInfo, X86_64GOTEntry> SymGOTMap;
186  typedef KeyEntryMap<ResolveInfo, X86_64GOTEntry> SymGOTPLTMap;
187  typedef KeyEntryMap<Relocation, Relocation> RelRelMap;
188
189public:
190  X86_64Relocator(X86_64GNULDBackend& pParent, const LinkerConfig& pConfig);
191
192  Result applyRelocation(Relocation& pRelocation);
193
194  X86_64GNULDBackend& getTarget()
195  { return m_Target; }
196
197  const X86_64GNULDBackend& getTarget() const
198  { return m_Target; }
199
200  const char* getName(Relocation::Type pType) const;
201
202  Size getSize(Relocation::Type pType) const;
203
204  const SymGOTMap& getSymGOTMap() const { return m_SymGOTMap; }
205  SymGOTMap&       getSymGOTMap()       { return m_SymGOTMap; }
206
207  const SymGOTPLTMap& getSymGOTPLTMap() const { return m_SymGOTPLTMap; }
208  SymGOTPLTMap&       getSymGOTPLTMap()       { return m_SymGOTPLTMap; }
209
210  const RelRelMap& getRelRelMap() const { return m_RelRelMap; }
211  RelRelMap&       getRelRelMap()       { return m_RelRelMap; }
212
213private:
214  void scanLocalReloc(Relocation& pReloc,
215                      IRBuilder& pBuilder,
216                      Module& pModule,
217                      LDSection& pSection);
218
219  void scanGlobalReloc(Relocation& pReloc,
220                       IRBuilder& pBuilder,
221                       Module& pModule,
222                       LDSection& pSection);
223
224private:
225  X86_64GNULDBackend& m_Target;
226  SymGOTMap m_SymGOTMap;
227  SymGOTPLTMap m_SymGOTPLTMap;
228  RelRelMap m_RelRelMap;
229};
230
231} // namespace of mcld
232
233#endif
234
235