MCObjectFileInfo.h revision 203576aa0cb9d8bf2d2e4d910ebab4b7a63262ae 
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/MC/MCCodeGenInfo.h"
18#include "llvm/ADT/StringRef.h"
19#include "llvm/MC/SectionKind.h"
20
21namespace llvm {
22class MCContext;
23class MCSection;
24class Triple;
25
26class MCObjectFileInfo {
27protected:
28  /// CommDirectiveSupportsAlignment - True if .comm supports alignment.  This
29  /// is a hack for as long as we support 10.4 Tiger, whose assembler doesn't
30  /// support alignment on comm.
31  bool CommDirectiveSupportsAlignment;
32
33  /// SupportsWeakEmptyEHFrame - True if target object file supports a
34  /// weak_definition of constant 0 for an omitted EH frame.
35  bool SupportsWeakOmittedEHFrame;
36
37  /// IsFunctionEHFrameSymbolPrivate - This flag is set to true if the
38  /// "EH_frame" symbol for EH information should be an assembler temporary (aka
39  /// private linkage, aka an L or .L label) or false if it should be a normal
40  /// non-.globl label.  This defaults to true.
41  bool IsFunctionEHFrameSymbolPrivate;
42
43  /// PersonalityEncoding, LSDAEncoding, FDEEncoding, TTypeEncoding - Some
44  /// encoding values for EH.
45  unsigned PersonalityEncoding;
46  unsigned LSDAEncoding;
47  unsigned FDEEncoding;
48  unsigned FDECFIEncoding;
49  unsigned TTypeEncoding;
50
51  /// TextSection - Section directive for standard text.
52  ///
53  const MCSection *TextSection;
54
55  /// DataSection - Section directive for standard data.
56  ///
57  const MCSection *DataSection;
58
59  /// BSSSection - Section that is default initialized to zero.
60  const MCSection *BSSSection;
61
62  /// ReadOnlySection - Section that is readonly and can contain arbitrary
63  /// initialized data.  Targets are not required to have a readonly section.
64  /// If they don't, various bits of code will fall back to using the data
65  /// section for constants.
66  const MCSection *ReadOnlySection;
67
68  /// StaticCtorSection - This section contains the static constructor pointer
69  /// list.
70  const MCSection *StaticCtorSection;
71
72  /// StaticDtorSection - This section contains the static destructor pointer
73  /// list.
74  const MCSection *StaticDtorSection;
75
76  /// LSDASection - If exception handling is supported by the target, this is
77  /// the section the Language Specific Data Area information is emitted to.
78  const MCSection *LSDASection;
79
80  /// CompactUnwindSection - If exception handling is supported by the target
81  /// and the target can support a compact representation of the CIE and FDE,
82  /// this is the section to emit them into.
83  const MCSection *CompactUnwindSection;
84
85  // Dwarf sections for debug info.  If a target supports debug info, these must
86  // be set.
87  const MCSection *DwarfAbbrevSection;
88  const MCSection *DwarfInfoSection;
89  const MCSection *DwarfLineSection;
90  const MCSection *DwarfFrameSection;
91  const MCSection *DwarfPubNamesSection;
92  const MCSection *DwarfPubTypesSection;
93  const MCSection *DwarfDebugInlineSection;
94  const MCSection *DwarfStrSection;
95  const MCSection *DwarfLocSection;
96  const MCSection *DwarfARangesSection;
97  const MCSection *DwarfRangesSection;
98  const MCSection *DwarfMacroInfoSection;
99
100  // Extra TLS Variable Data section.  If the target needs to put additional
101  // information for a TLS variable, it'll go here.
102  const MCSection *TLSExtraDataSection;
103
104  /// TLSDataSection - Section directive for Thread Local data.
105  /// ELF and MachO only.
106  const MCSection *TLSDataSection;        // Defaults to ".tdata".
107
108  /// TLSBSSSection - Section directive for Thread Local uninitialized data.
109  /// Null if this target doesn't support a BSS section.
110  /// ELF and MachO only.
111  const MCSection *TLSBSSSection;         // Defaults to ".tbss".
112
113
114  /// EHFrameSection - EH frame section. It is initialized on demand so it
115  /// can be overwritten (with uniquing).
116  const MCSection *EHFrameSection;
117
118  /// ELF specific sections.
119  ///
120  const MCSection *DataRelSection;
121  const MCSection *DataRelLocalSection;
122  const MCSection *DataRelROSection;
123  const MCSection *DataRelROLocalSection;
124  const MCSection *MergeableConst4Section;
125  const MCSection *MergeableConst8Section;
126  const MCSection *MergeableConst16Section;
127
128  /// MachO specific sections.
129  ///
130
131  /// TLSTLVSection - Section for thread local structure information.
132  /// Contains the source code name of the variable, visibility and a pointer
133  /// to the initial value (.tdata or .tbss).
134  const MCSection *TLSTLVSection;         // Defaults to ".tlv".
135
136  /// TLSThreadInitSection - Section for thread local data initialization
137  /// functions.
138  const MCSection *TLSThreadInitSection;  // Defaults to ".thread_init_func".
139
140  const MCSection *CStringSection;
141  const MCSection *UStringSection;
142  const MCSection *TextCoalSection;
143  const MCSection *ConstTextCoalSection;
144  const MCSection *ConstDataSection;
145  const MCSection *DataCoalSection;
146  const MCSection *DataCommonSection;
147  const MCSection *DataBSSSection;
148  const MCSection *FourByteConstantSection;
149  const MCSection *EightByteConstantSection;
150  const MCSection *SixteenByteConstantSection;
151  const MCSection *LazySymbolPointerSection;
152  const MCSection *NonLazySymbolPointerSection;
153
154  /// COFF specific sections.
155  ///
156  const MCSection *DrectveSection;
157  const MCSection *PDataSection;
158  const MCSection *XDataSection;
159
160public:
161  void InitMCObjectFileInfo(StringRef TT, Reloc::Model RM, CodeModel::Model CM,
162                            MCContext &ctx);
163
164  bool isFunctionEHFrameSymbolPrivate() const {
165    return IsFunctionEHFrameSymbolPrivate;
166  }
167  bool getSupportsWeakOmittedEHFrame() const {
168    return SupportsWeakOmittedEHFrame;
169  }
170  bool getCommDirectiveSupportsAlignment() const {
171    return CommDirectiveSupportsAlignment;
172  }
173
174  unsigned getPersonalityEncoding() const { return PersonalityEncoding; }
175  unsigned getLSDAEncoding() const { return LSDAEncoding; }
176  unsigned getFDEEncoding(bool CFI) const {
177    return CFI ? FDECFIEncoding : FDEEncoding;
178  }
179  unsigned getTTypeEncoding() const { return TTypeEncoding; }
180
181  const MCSection *getTextSection() const { return TextSection; }
182  const MCSection *getDataSection() const { return DataSection; }
183  const MCSection *getBSSSection() const { return BSSSection; }
184  const MCSection *getStaticCtorSection() const { return StaticCtorSection; }
185  const MCSection *getStaticDtorSection() const { return StaticDtorSection; }
186  const MCSection *getLSDASection() const { return LSDASection; }
187  const MCSection *getCompactUnwindSection() const{
188    return CompactUnwindSection;
189  }
190  const MCSection *getDwarfAbbrevSection() const { return DwarfAbbrevSection; }
191  const MCSection *getDwarfInfoSection() const { return DwarfInfoSection; }
192  const MCSection *getDwarfLineSection() const { return DwarfLineSection; }
193  const MCSection *getDwarfFrameSection() const { return DwarfFrameSection; }
194  const MCSection *getDwarfPubNamesSection() const{return DwarfPubNamesSection;}
195  const MCSection *getDwarfPubTypesSection() const{return DwarfPubTypesSection;}
196  const MCSection *getDwarfDebugInlineSection() const {
197    return DwarfDebugInlineSection;
198  }
199  const MCSection *getDwarfStrSection() const { return DwarfStrSection; }
200  const MCSection *getDwarfLocSection() const { return DwarfLocSection; }
201  const MCSection *getDwarfARangesSection() const { return DwarfARangesSection;}
202  const MCSection *getDwarfRangesSection() const { return DwarfRangesSection; }
203  const MCSection *getDwarfMacroInfoSection() const {
204    return DwarfMacroInfoSection;
205  }
206  const MCSection *getTLSExtraDataSection() const {
207    return TLSExtraDataSection;
208  }
209  const MCSection *getTLSDataSection() const { return TLSDataSection; }
210  const MCSection *getTLSBSSSection() const { return TLSBSSSection; }
211
212  /// ELF specific sections.
213  ///
214  const MCSection *getDataRelSection() const { return DataRelSection; }
215  const MCSection *getDataRelLocalSection() const {
216    return DataRelLocalSection;
217  }
218  const MCSection *getDataRelROSection() const { return DataRelROSection; }
219  const MCSection *getDataRelROLocalSection() const {
220    return DataRelROLocalSection;
221  }
222  const MCSection *getMergeableConst4Section() const {
223    return MergeableConst4Section;
224  }
225  const MCSection *getMergeableConst8Section() const {
226    return MergeableConst8Section;
227  }
228  const MCSection *getMergeableConst16Section() const {
229    return MergeableConst16Section;
230  }
231
232  /// MachO specific sections.
233  ///
234  const MCSection *getTLSTLVSection() const { return TLSTLVSection; }
235  const MCSection *getTLSThreadInitSection() const {
236    return TLSThreadInitSection;
237  }
238  const MCSection *getCStringSection() const { return CStringSection; }
239  const MCSection *getUStringSection() const { return UStringSection; }
240  const MCSection *getTextCoalSection() const { return TextCoalSection; }
241  const MCSection *getConstTextCoalSection() const {
242    return ConstTextCoalSection;
243  }
244  const MCSection *getConstDataSection() const { return ConstDataSection; }
245  const MCSection *getDataCoalSection() const { return DataCoalSection; }
246  const MCSection *getDataCommonSection() const { return DataCommonSection; }
247  const MCSection *getDataBSSSection() const { return DataBSSSection; }
248  const MCSection *getFourByteConstantSection() const {
249    return FourByteConstantSection;
250  }
251  const MCSection *getEightByteConstantSection() const {
252    return EightByteConstantSection;
253  }
254  const MCSection *getSixteenByteConstantSection() const {
255    return SixteenByteConstantSection;
256  }
257  const MCSection *getLazySymbolPointerSection() const {
258    return LazySymbolPointerSection;
259  }
260  const MCSection *getNonLazySymbolPointerSection() const {
261    return NonLazySymbolPointerSection;
262  }
263
264  /// COFF specific sections.
265  ///
266  const MCSection *getDrectveSection() const { return DrectveSection; }
267  const MCSection *getPDataSection() const { return PDataSection; }
268  const MCSection *getXDataSection() const { return XDataSection; }
269
270  const MCSection *getEHFrameSection() {
271    if (!EHFrameSection)
272      InitEHFrameSection();
273    return EHFrameSection;
274  }
275
276private:
277  enum Environment { IsMachO, IsELF, IsCOFF };
278  Environment Env;
279  Reloc::Model RelocM;
280  CodeModel::Model CMModel;
281  MCContext *Ctx;
282
283  void InitMachOMCObjectFileInfo(Triple T);
284  void InitELFMCObjectFileInfo(Triple T);
285  void InitCOFFMCObjectFileInfo(Triple T);
286
287  /// InitEHFrameSection - Initialize EHFrameSection on demand.
288  ///
289  void InitEHFrameSection();
290};
291
292} // end namespace llvm
293
294#endif
295