LLVM  8.0.0svn
MCObjectFileInfo.h
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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_MCOBJECTFILEINFO_H
15 #define LLVM_MC_MCOBJECTFILEINFO_H
16 
17 #include "llvm/ADT/DenseMap.h"
18 #include "llvm/ADT/Triple.h"
19 #include "llvm/MC/MCSymbol.h"
20 #include "llvm/Support/CodeGen.h"
21 
22 namespace llvm {
23 class MCContext;
24 class MCSection;
25 
27 protected:
28  /// True if .comm supports alignment. This is a hack for as long as we
29  /// support 10.4 Tiger, whose assembler doesn't support alignment on comm.
31 
32  /// True if target object file supports a weak_definition of constant 0 for an
33  /// omitted EH frame.
35 
36  /// True if the target object file supports emitting a compact unwind section
37  /// without an associated EH frame section.
39 
40  /// OmitDwarfIfHaveCompactUnwind - True if the target object file
41  /// supports having some functions with compact unwind and other with
42  /// dwarf unwind.
44 
45  /// FDE CFI encoding. Controls the encoding of the begin label in the
46  /// .eh_frame section. Unlike the LSDA encoding, personality encoding, and
47  /// type encodings, this is something that the assembler just "knows" about
48  /// its target
49  unsigned FDECFIEncoding = 0;
50 
51  /// Compact unwind encoding indicating that we should emit only an EH frame.
53 
54  /// Section directive for standard text.
56 
57  /// Section directive for standard data.
59 
60  /// Section that is default initialized to zero.
62 
63  /// Section that is readonly and can contain arbitrary initialized data.
64  /// Targets are not required to have a readonly section. If they don't,
65  /// various bits of code will fall back to using the data section for
66  /// constants.
68 
69  /// If exception handling is supported by the target, this is the section the
70  /// Language Specific Data Area information is emitted to.
72 
73  /// If exception handling is supported by the target and the target can
74  /// support a compact representation of the CIE and FDE, this is the section
75  /// to emit them into.
77 
78  // Dwarf sections for debug info. If a target supports debug info, these must
79  // be set.
92  // The pubnames section is no longer generated by default. The generation
93  // can be enabled by a compiler flag.
95 
96  /// Accelerator table sections. DwarfDebugNamesSection is the DWARF v5
97  /// accelerator table, while DwarfAccelNamesSection, DwarfAccelObjCSection,
98  /// DwarfAccelNamespaceSection, DwarfAccelTypesSection are pre-DWARF v5
99  /// extensions.
105 
106  // These are used for the Fission separate debug information files.
114 
115  /// The DWARF v5 string offset and address table sections.
118  /// The DWARF v5 range list section.
120  /// The DWARF v5 locations list section.
122 
123  /// The DWARF v5 range list section for fission.
125 
126  // These are for Fission DWP files.
129 
130  /// Section for newer gnu pubnames.
132  /// Section for newer gnu pubtypes.
134 
135  // Section for Swift AST
137 
141 
142  /// Extra TLS Variable Data section.
143  ///
144  /// If the target needs to put additional information for a TLS variable,
145  /// it'll go here.
147 
148  /// Section directive for Thread Local data. ELF, MachO, COFF, and Wasm.
149  MCSection *TLSDataSection; // Defaults to ".tdata".
150 
151  /// Section directive for Thread Local uninitialized data.
152  ///
153  /// Null if this target doesn't support a BSS section. ELF and MachO only.
154  MCSection *TLSBSSSection; // Defaults to ".tbss".
155 
156  /// StackMap section.
158 
159  /// FaultMap section.
161 
162  /// EH frame section.
163  ///
164  /// It is initialized on demand so it can be overwritten (with uniquing).
166 
167  /// Section containing metadata on function stack sizes.
170 
171  // ELF specific sections.
177 
178  // MachO specific sections.
179 
180  /// Section for thread local structure information.
181  ///
182  /// Contains the source code name of the variable, visibility and a pointer to
183  /// the initial value (.tdata or .tbss).
184  MCSection *TLSTLVSection; // Defaults to ".tlv".
185 
186  /// Section for thread local data initialization functions.
187  const MCSection *TLSThreadInitSection; // Defaults to ".thread_init_func".
188 
204 
205  /// COFF specific sections.
211 
212 public:
213  void InitMCObjectFileInfo(const Triple &TT, bool PIC, MCContext &ctx,
214  bool LargeCodeModel = false);
215 
218  }
221  }
224  }
225 
228  }
229 
230  unsigned getFDEEncoding() const { return FDECFIEncoding; }
231 
234  }
235 
236  MCSection *getTextSection() const { return TextSection; }
237  MCSection *getDataSection() const { return DataSection; }
238  MCSection *getBSSSection() const { return BSSSection; }
240  MCSection *getLSDASection() const { return LSDASection; }
244  MCSection *getDwarfInfoSection(uint64_t Hash) const {
245  return getDwarfComdatSection(".debug_info", Hash);
246  }
254  }
257  }
260  }
268 
270  return DwarfDebugNamesSection;
271  }
273  return DwarfAccelNamesSection;
274  }
278  }
280  return DwarfAccelTypesSection;
281  }
283  MCSection *getDwarfTypesSection(uint64_t Hash) const {
284  return getDwarfComdatSection(".debug_types", Hash);
285  }
296  }
300 
303  }
305  return COFFDebugTypesSection;
306  }
309  }
310 
312  const MCSection *getTLSDataSection() const { return TLSDataSection; }
314 
317 
318  MCSection *getStackSizesSection(const MCSection &TextSec) const;
319 
320  // ELF specific sections.
323  return MergeableConst4Section;
324  }
326  return MergeableConst8Section;
327  }
330  }
333  }
334 
335  // MachO specific sections.
336  const MCSection *getTLSTLVSection() const { return TLSTLVSection; }
338  return TLSThreadInitSection;
339  }
340  const MCSection *getCStringSection() const { return CStringSection; }
341  const MCSection *getUStringSection() const { return UStringSection; }
344  return ConstTextCoalSection;
345  }
346  const MCSection *getConstDataSection() const { return ConstDataSection; }
347  const MCSection *getDataCoalSection() const { return DataCoalSection; }
349  return ConstDataCoalSection;
350  }
355  }
358  }
361  }
364  }
367  }
370  }
371 
372  // COFF specific sections.
378 
380  return EHFrameSection;
381  }
382 
384  Environment getObjectFileType() const { return Env; }
385 
386  bool isPositionIndependent() const { return PositionIndependent; }
387 
388 private:
389  Environment Env;
390  bool PositionIndependent;
391  MCContext *Ctx;
392  Triple TT;
393 
394  void initMachOMCObjectFileInfo(const Triple &T);
395  void initELFMCObjectFileInfo(const Triple &T, bool Large);
396  void initCOFFMCObjectFileInfo(const Triple &T);
397  void initWasmMCObjectFileInfo(const Triple &T);
398  MCSection *getDwarfComdatSection(const char *Name, uint64_t Hash) const;
399 
400 public:
401  const Triple &getTargetTriple() const { return TT; }
402 };
403 
404 } // end namespace llvm
405 
406 #endif
Instances of this class represent a uniqued identifier for a section in the current translation unit...
Definition: MCSection.h:39
MCSection * MergeableConst4Section
MCSection * DwarfStrOffSection
The DWARF v5 string offset and address table sections.
const MCSection * getConstDataSection() const
MCSection * getDwarfStrOffSection() const
MCSection * getDwarfTUIndexSection() const
MCSection * getDwarfAccelObjCSection() const
MCSection * getDwarfCUIndexSection() const
MCSection * getDwarfStrSection() const
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
MCSection * getCOFFDebugTypesSection() const
const MCSection * getTLSTLVSection() const
MCSection * getDwarfLineSection() const
MCSection * getStackMapSection() const
MCSection * DwarfPubTypesSection
MCSection * getDwarfLocSection() const
MCSection * DwarfGnuPubTypesSection
Section for newer gnu pubtypes.
MCSection * getTLSBSSSection() const
const MCSection * getFourByteConstantSection() const
MCSection * StackMapSection
StackMap section.
MCSection * SixteenByteConstantSection
MCSection * DwarfRnglistsSection
The DWARF v5 range list section.
MCSection * TextSection
Section directive for standard text.
MCSection * getEHFrameSection()
MCSection * ConstTextCoalSection
MCSection * getDwarfAccelNamesSection() const
const MCSection * getConstDataCoalSection() const
MCSection * LazySymbolPointerSection
MCSection * getDwarfLineStrSection() const
MCSection * getDwarfARangesSection() const
bool getSupportsCompactUnwindWithoutEHFrame() const
MCSection * getCOFFGlobalTypeHashesSection() const
MCSection * getDwarfRnglistsDWOSection() const
MCSection * getDwarfRnglistsSection() const
MCSection * getDwarfPubNamesSection() const
MCSection * getReadOnlySection() const
MCSection * MergeableConst32Section
MCSection * DwarfDebugNamesSection
Accelerator table sections.
amdgpu Simplify well known AMD library false Value Value const Twine & Name
MCSection * getDwarfMacinfoSection() const
MCSection * getDwarfLocDWOSection() const
MCSection * COFFDebugTypesSection
const MCSection * getCStringSection() const
MCSection * MergeableConst16Section
MCSection * DwarfPubNamesSection
bool getCommDirectiveSupportsAlignment() const
MCSection * getBSSSection() const
MCSection * getDataSection() const
MCSection * EightByteConstantSection
unsigned getCompactUnwindDwarfEHFrameOnly() const
MCSection * getStackSizesSection(const MCSection &TextSec) const
MCSection * getDwarfFrameSection() const
MCSection * TLSDataSection
Section directive for Thread Local data. ELF, MachO, COFF, and Wasm.
MCSection * getDwarfTypesSection(uint64_t Hash) const
MCSection * getDataBSSSection() const
bool getOmitDwarfIfHaveCompactUnwind() const
Context object for machine code objects.
Definition: MCContext.h:63
MCSection * getSXDataSection() const
const MCSection * DwarfDebugInlineSection
const MCSection * getDwarfDebugInlineSection() const
bool getSupportsWeakOmittedEHFrame() const
MCSection * getCOFFDebugSymbolsSection() const
MCSection * ConstDataCoalSection
MCSection * DrectveSection
COFF specific sections.
MCSection * getCompactUnwindSection() const
MCSection * getPDataSection() const
MCSection * DwarfAccelNamesSection
MCSection * getGFIDsSection() const
const MCSection * getMergeableConst16Section() const
MCSection * getDwarfAccelTypesSection() const
MCSection * getDwarfAbbrevSection() const
MCSection * DataSection
Section directive for standard data.
MCSection * getDwarfAbbrevDWOSection() const
MCSection * getTLSExtraDataSection() const
MCSection * getDwarfGnuPubTypesSection() const
MCSection * getDwarfTypesDWOSection() const
MCSection * ThreadLocalPointerSection
MCSection * DwarfLineStrSection
MCSection * getDwarfAddrSection() const
MCSection * DwarfSwiftASTSection
MCSection * TLSTLVSection
Section for thread local structure information.
MCSection * getNonLazySymbolPointerSection() const
unsigned getFDEEncoding() const
MCSection * DwarfAccelNamespaceSection
MCSection * getDwarfLineDWOSection() const
const MCSection * getMergeableConst8Section() const
Environment getObjectFileType() const
bool SupportsCompactUnwindWithoutEHFrame
True if the target object file supports emitting a compact unwind section without an associated EH fr...
MCSection * getDwarfSwiftASTSection() const
bool CommDirectiveSupportsAlignment
True if .comm supports alignment.
Triple - Helper class for working with autoconf configuration names.
Definition: Triple.h:44
MCSection * getDrectveSection() const
MCSection * COFFDebugSymbolsSection
MCSection * DwarfAbbrevSection
MCSection * getThreadLocalPointerSection() const
MCSection * EHFrameSection
EH frame section.
const MCSection * getEightByteConstantSection() const
MCSection * getDataRelROSection() const
MCSection * DwarfLoclistsSection
The DWARF v5 locations list section.
MCSection * DwarfTypesDWOSection
MCSection * DwarfRangesSection
const MCSection * getConstTextCoalSection() const
const Triple & getTargetTriple() const
MCSection * DwarfARangesSection
const MCSection * getDataCommonSection() const
MCSection * CompactUnwindSection
If exception handling is supported by the target and the target can support a compact representation ...
MCSection * getDwarfInfoSection() const
MCSection * DwarfAccelTypesSection
MCSection * getDwarfDebugNamesSection() const
MCSection * getDwarfStrOffDWOSection() const
DenseMap< const MCSymbol *, unsigned > StackSizesUniquing
MCSection * DwarfStrOffDWOSection
MCSection * getDwarfInfoSection(uint64_t Hash) const
MCSection * DwarfGnuPubNamesSection
Section for newer gnu pubnames.
MCSection * DwarfAbbrevDWOSection
const MCSection * getMergeableConst4Section() const
MCSection * getDwarfPubTypesSection() const
MCSection * FaultMapSection
FaultMap section.
bool OmitDwarfIfHaveCompactUnwind
OmitDwarfIfHaveCompactUnwind - True if the target object file supports having some functions with com...
MCSection * FourByteConstantSection
void InitMCObjectFileInfo(const Triple &TT, bool PIC, MCContext &ctx, bool LargeCodeModel=false)
unsigned FDECFIEncoding
FDE CFI encoding.
MCSection * getDwarfStrDWOSection() const
const MCSection * getMergeableConst32Section() const
MCSection * getXDataSection() const
MCSection * LSDASection
If exception handling is supported by the target, this is the section the Language Specific Data Area...
MCSection * TLSExtraDataSection
Extra TLS Variable Data section.
MCSection * getLazySymbolPointerSection() const
unsigned CompactUnwindDwarfEHFrameOnly
Compact unwind encoding indicating that we should emit only an EH frame.
MCSection * StackSizesSection
Section containing metadata on function stack sizes.
MCSection * getDwarfGnuPubNamesSection() const
MCSection * DwarfAccelObjCSection
MCSection * getFaultMapSection() const
const MCSection * getTLSThreadInitSection() const
MCSection * getTextSection() const
MCSection * COFFGlobalTypeHashesSection
MCSection * TLSBSSSection
Section directive for Thread Local uninitialized data.
MCSection * NonLazySymbolPointerSection
MCSection * getDwarfAccelNamespaceSection() const
const MCSection * TLSThreadInitSection
Section for thread local data initialization functions.
MCSection * DwarfRnglistsDWOSection
The DWARF v5 range list section for fission.
bool SupportsWeakOmittedEHFrame
True if target object file supports a weak_definition of constant 0 for an omitted EH frame...
MCSection * getLSDASection() const
MCSection * getDwarfInfoDWOSection() const
MCSection * BSSSection
Section that is default initialized to zero.
MCSection * ReadOnlySection
Section that is readonly and can contain arbitrary initialized data.
bool isPositionIndependent() const
MCSection * DwarfMacinfoSection
MCSection * getDwarfRangesSection() const
const MCSection * getTLSDataSection() const
const MCSection * getSixteenByteConstantSection() const
const MCSection * getUStringSection() const
MCSection * getTextCoalSection() const
const MCSection * getDataCoalSection() const
MCSection * getDwarfLoclistsSection() const
MCSection * MergeableConst8Section