MCObjectFileInfo.h revision 639aa87bee77fe2d83f0978ae1eea53e49def324 
1//===-- llvm/MC/MCObjectFileInfo.h - Object File Info -----------*- 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// This file describes common object file formats.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_MC_MCBJECTFILEINFO_H
15#define LLVM_MC_MCBJECTFILEINFO_H
16
17#include "llvm/Support/CodeGen.h"
18
19namespace llvm {
20  class MCContext;
21  class MCSection;
22  class StringRef;
23  class Triple;
24
25class MCObjectFileInfo {
26protected:
27  /// CommDirectiveSupportsAlignment - True if .comm supports alignment.  This
28  /// is a hack for as long as we support 10.4 Tiger, whose assembler doesn't
29  /// support alignment on comm.
30  bool CommDirectiveSupportsAlignment;
31
32  /// SupportsWeakEmptyEHFrame - True if target object file supports a
33  /// weak_definition of constant 0 for an omitted EH frame.
34  bool SupportsWeakOmittedEHFrame;
35
36  /// IsFunctionEHFrameSymbolPrivate - This flag is set to true if the
37  /// "EH_frame" symbol for EH information should be an assembler temporary (aka
38  /// private linkage, aka an L or .L label) or false if it should be a normal
39  /// non-.globl label.  This defaults to true.
40  bool IsFunctionEHFrameSymbolPrivate;
41
42  /// PersonalityEncoding, LSDAEncoding, FDEEncoding, TTypeEncoding - Some
43  /// encoding values for EH.
44  unsigned PersonalityEncoding;
45  unsigned LSDAEncoding;
46  unsigned FDEEncoding;
47  unsigned FDECFIEncoding;
48  unsigned TTypeEncoding;
49  // Section flags for eh_frame
50  unsigned EHSectionType;
51  unsigned EHSectionFlags;
52
53  /// TextSection - Section directive for standard text.
54  ///
55  const MCSection *TextSection;
56
57  /// DataSection - Section directive for standard data.
58  ///
59  const MCSection *DataSection;
60
61  /// BSSSection - Section that is default initialized to zero.
62  const MCSection *BSSSection;
63
64  /// ReadOnlySection - Section that is readonly and can contain arbitrary
65  /// initialized data.  Targets are not required to have a readonly section.
66  /// If they don't, various bits of code will fall back to using the data
67  /// section for constants.
68  const MCSection *ReadOnlySection;
69
70  /// StaticCtorSection - This section contains the static constructor pointer
71  /// list.
72  const MCSection *StaticCtorSection;
73
74  /// StaticDtorSection - This section contains the static destructor pointer
75  /// list.
76  const MCSection *StaticDtorSection;
77
78  /// LSDASection - If exception handling is supported by the target, this is
79  /// the section the Language Specific Data Area information is emitted to.
80  const MCSection *LSDASection;
81
82  /// CompactUnwindSection - If exception handling is supported by the target
83  /// and the target can support a compact representation of the CIE and FDE,
84  /// this is the section to emit them into.
85  const MCSection *CompactUnwindSection;
86
87  /// DwarfAccelNamesSection, DwarfAccelObjCSection
88  /// If we use the DWARF accelerated hash tables then we want toe emit these
89  /// sections.
90  const MCSection *DwarfAccelNamesSection;
91  const MCSection *DwarfAccelObjCSection;
92  const MCSection *DwarfAccelNamespaceSection;
93  const MCSection *DwarfAccelTypesSection;
94
95  // Dwarf sections for debug info.  If a target supports debug info, these must
96  // be set.
97  const MCSection *DwarfAbbrevSection;
98  const MCSection *DwarfInfoSection;
99  const MCSection *DwarfLineSection;
100  const MCSection *DwarfFrameSection;
101  const MCSection *DwarfPubTypesSection;
102  const MCSection *DwarfDebugInlineSection;
103  const MCSection *DwarfStrSection;
104  const MCSection *DwarfLocSection;
105  const MCSection *DwarfARangesSection;
106  const MCSection *DwarfRangesSection;
107  const MCSection *DwarfMacroInfoSection;
108
109  // Extra TLS Variable Data section.  If the target needs to put additional
110  // information for a TLS variable, it'll go here.
111  const MCSection *TLSExtraDataSection;
112
113  /// TLSDataSection - Section directive for Thread Local data.
114  /// ELF, MachO and COFF.
115  const MCSection *TLSDataSection;        // Defaults to ".tdata".
116
117  /// TLSBSSSection - Section directive for Thread Local uninitialized data.
118  /// Null if this target doesn't support a BSS section.
119  /// ELF and MachO only.
120  const MCSection *TLSBSSSection;         // Defaults to ".tbss".
121
122
123  /// EHFrameSection - EH frame section. It is initialized on demand so it
124  /// can be overwritten (with uniquing).
125  const MCSection *EHFrameSection;
126
127  /// ELF specific sections.
128  ///
129  const MCSection *DataRelSection;
130  const MCSection *DataRelLocalSection;
131  const MCSection *DataRelROSection;
132  const MCSection *DataRelROLocalSection;
133  const MCSection *MergeableConst4Section;
134  const MCSection *MergeableConst8Section;
135  const MCSection *MergeableConst16Section;
136
137  /// MachO specific sections.
138  ///
139
140  /// TLSTLVSection - Section for thread local structure information.
141  /// Contains the source code name of the variable, visibility and a pointer
142  /// to the initial value (.tdata or .tbss).
143  const MCSection *TLSTLVSection;         // Defaults to ".tlv".
144
145  /// TLSThreadInitSection - Section for thread local data initialization
146  /// functions.
147  const MCSection *TLSThreadInitSection;  // Defaults to ".thread_init_func".
148
149  const MCSection *CStringSection;
150  const MCSection *UStringSection;
151  const MCSection *TextCoalSection;
152  const MCSection *ConstTextCoalSection;
153  const MCSection *ConstDataSection;
154  const MCSection *DataCoalSection;
155  const MCSection *DataCommonSection;
156  const MCSection *DataBSSSection;
157  const MCSection *FourByteConstantSection;
158  const MCSection *EightByteConstantSection;
159  const MCSection *SixteenByteConstantSection;
160  const MCSection *LazySymbolPointerSection;
161  const MCSection *NonLazySymbolPointerSection;
162
163  /// COFF specific sections.
164  ///
165  const MCSection *DrectveSection;
166  const MCSection *PDataSection;
167  const MCSection *XDataSection;
168
169public:
170  void InitMCObjectFileInfo(StringRef TT, Reloc::Model RM, CodeModel::Model CM,
171                            MCContext &ctx);
172
173  bool isFunctionEHFrameSymbolPrivate() const {
174    return IsFunctionEHFrameSymbolPrivate;
175  }
176  bool getSupportsWeakOmittedEHFrame() const {
177    return SupportsWeakOmittedEHFrame;
178  }
179  bool getCommDirectiveSupportsAlignment() const {
180    return CommDirectiveSupportsAlignment;
181  }
182
183  unsigned getPersonalityEncoding() const { return PersonalityEncoding; }
184  unsigned getLSDAEncoding() const { return LSDAEncoding; }
185  unsigned getFDEEncoding(bool CFI) const {
186    return CFI ? FDECFIEncoding : FDEEncoding;
187  }
188  unsigned getTTypeEncoding() const { return TTypeEncoding; }
189
190  const MCSection *getTextSection() const { return TextSection; }
191  const MCSection *getDataSection() const { return DataSection; }
192  const MCSection *getBSSSection() const { return BSSSection; }
193  const MCSection *getLSDASection() const { return LSDASection; }
194  const MCSection *getCompactUnwindSection() const{
195    return CompactUnwindSection;
196  }
197  const MCSection *getDwarfAccelNamesSection() const {
198    return DwarfAccelNamesSection;
199  }
200  const MCSection *getDwarfAccelObjCSection() const {
201    return DwarfAccelObjCSection;
202  }
203  const MCSection *getDwarfAccelNamespaceSection() const {
204    return DwarfAccelNamespaceSection;
205  }
206  const MCSection *getDwarfAccelTypesSection() const {
207    return DwarfAccelTypesSection;
208  }
209  const MCSection *getDwarfAbbrevSection() const { return DwarfAbbrevSection; }
210  const MCSection *getDwarfInfoSection() const { return DwarfInfoSection; }
211  const MCSection *getDwarfLineSection() const { return DwarfLineSection; }
212  const MCSection *getDwarfFrameSection() const { return DwarfFrameSection; }
213  const MCSection *getDwarfPubTypesSection() const{return DwarfPubTypesSection;}
214  const MCSection *getDwarfDebugInlineSection() const {
215    return DwarfDebugInlineSection;
216  }
217  const MCSection *getDwarfStrSection() const { return DwarfStrSection; }
218  const MCSection *getDwarfLocSection() const { return DwarfLocSection; }
219  const MCSection *getDwarfARangesSection() const { return DwarfARangesSection;}
220  const MCSection *getDwarfRangesSection() const { return DwarfRangesSection; }
221  const MCSection *getDwarfMacroInfoSection() const {
222    return DwarfMacroInfoSection;
223  }
224  const MCSection *getTLSExtraDataSection() const {
225    return TLSExtraDataSection;
226  }
227  const MCSection *getTLSDataSection() const { return TLSDataSection; }
228  const MCSection *getTLSBSSSection() const { return TLSBSSSection; }
229
230  /// ELF specific sections.
231  ///
232  const MCSection *getDataRelSection() const { return DataRelSection; }
233  const MCSection *getDataRelLocalSection() const {
234    return DataRelLocalSection;
235  }
236  const MCSection *getDataRelROSection() const { return DataRelROSection; }
237  const MCSection *getDataRelROLocalSection() const {
238    return DataRelROLocalSection;
239  }
240  const MCSection *getMergeableConst4Section() const {
241    return MergeableConst4Section;
242  }
243  const MCSection *getMergeableConst8Section() const {
244    return MergeableConst8Section;
245  }
246  const MCSection *getMergeableConst16Section() const {
247    return MergeableConst16Section;
248  }
249
250  /// MachO specific sections.
251  ///
252  const MCSection *getTLSTLVSection() const { return TLSTLVSection; }
253  const MCSection *getTLSThreadInitSection() const {
254    return TLSThreadInitSection;
255  }
256  const MCSection *getCStringSection() const { return CStringSection; }
257  const MCSection *getUStringSection() const { return UStringSection; }
258  const MCSection *getTextCoalSection() const { return TextCoalSection; }
259  const MCSection *getConstTextCoalSection() const {
260    return ConstTextCoalSection;
261  }
262  const MCSection *getConstDataSection() const { return ConstDataSection; }
263  const MCSection *getDataCoalSection() const { return DataCoalSection; }
264  const MCSection *getDataCommonSection() const { return DataCommonSection; }
265  const MCSection *getDataBSSSection() const { return DataBSSSection; }
266  const MCSection *getFourByteConstantSection() const {
267    return FourByteConstantSection;
268  }
269  const MCSection *getEightByteConstantSection() const {
270    return EightByteConstantSection;
271  }
272  const MCSection *getSixteenByteConstantSection() const {
273    return SixteenByteConstantSection;
274  }
275  const MCSection *getLazySymbolPointerSection() const {
276    return LazySymbolPointerSection;
277  }
278  const MCSection *getNonLazySymbolPointerSection() const {
279    return NonLazySymbolPointerSection;
280  }
281
282  /// COFF specific sections.
283  ///
284  const MCSection *getDrectveSection() const { return DrectveSection; }
285  const MCSection *getPDataSection() const { return PDataSection; }
286  const MCSection *getXDataSection() const { return XDataSection; }
287
288  const MCSection *getEHFrameSection() {
289    if (!EHFrameSection)
290      InitEHFrameSection();
291    return EHFrameSection;
292  }
293
294private:
295  enum Environment { IsMachO, IsELF, IsCOFF };
296  Environment Env;
297  Reloc::Model RelocM;
298  CodeModel::Model CMModel;
299  MCContext *Ctx;
300
301  void InitMachOMCObjectFileInfo(Triple T);
302  void InitELFMCObjectFileInfo(Triple T);
303  void InitCOFFMCObjectFileInfo(Triple T);
304
305  /// InitEHFrameSection - Initialize EHFrameSection on demand.
306  ///
307  void InitEHFrameSection();
308};
309
310} // end namespace llvm
311
312#endif
313