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RuntimeDyldImpl.h
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1 //===-- RuntimeDyldImpl.h - Run-time dynamic linker for MC-JIT --*- 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 // Interface for the implementations of runtime dynamic linker facilities.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_LIB_EXECUTIONENGINE_RUNTIMEDYLD_RUNTIMEDYLDIMPL_H
15 #define LLVM_LIB_EXECUTIONENGINE_RUNTIMEDYLD_RUNTIMEDYLDIMPL_H
16 
17 #include "llvm/ADT/SmallVector.h"
18 #include "llvm/ADT/StringMap.h"
19 #include "llvm/ADT/Triple.h"
23 #include "llvm/Object/ObjectFile.h"
24 #include "llvm/Support/Debug.h"
26 #include "llvm/Support/Format.h"
27 #include "llvm/Support/Host.h"
28 #include "llvm/Support/Mutex.h"
30 #include <map>
31 #include <system_error>
32 #include <unordered_map>
33 
34 using namespace llvm;
35 using namespace llvm::object;
36 
37 namespace llvm {
38 
39 class Twine;
40 
41 #define UNIMPLEMENTED_RELOC(RelType) \
42  case RelType: \
43  return make_error<RuntimeDyldError>("Unimplemented relocation: " #RelType)
44 
45 /// SectionEntry - represents a section emitted into memory by the dynamic
46 /// linker.
47 class SectionEntry {
48  /// Name - section name.
49  std::string Name;
50 
51  /// Address - address in the linker's memory where the section resides.
52  uint8_t *Address;
53 
54  /// Size - section size. Doesn't include the stubs.
55  size_t Size;
56 
57  /// LoadAddress - the address of the section in the target process's memory.
58  /// Used for situations in which JIT-ed code is being executed in the address
59  /// space of a separate process. If the code executes in the same address
60  /// space where it was JIT-ed, this just equals Address.
61  uint64_t LoadAddress;
62 
63  /// StubOffset - used for architectures with stub functions for far
64  /// relocations (like ARM).
65  uintptr_t StubOffset;
66 
67  /// The total amount of space allocated for this section. This includes the
68  /// section size and the maximum amount of space that the stubs can occupy.
69  size_t AllocationSize;
70 
71  /// ObjAddress - address of the section in the in-memory object file. Used
72  /// for calculating relocations in some object formats (like MachO).
73  uintptr_t ObjAddress;
74 
75 public:
76  SectionEntry(StringRef name, uint8_t *address, size_t size,
77  size_t allocationSize, uintptr_t objAddress)
78  : Name(name), Address(address), Size(size),
79  LoadAddress(reinterpret_cast<uintptr_t>(address)), StubOffset(size),
80  AllocationSize(allocationSize), ObjAddress(objAddress) {
81  // AllocationSize is used only in asserts, prevent an "unused private field"
82  // warning:
83  (void)AllocationSize;
84  }
85 
86  StringRef getName() const { return Name; }
87 
88  uint8_t *getAddress() const { return Address; }
89 
90  /// \brief Return the address of this section with an offset.
91  uint8_t *getAddressWithOffset(unsigned OffsetBytes) const {
92  assert(OffsetBytes <= AllocationSize && "Offset out of bounds!");
93  return Address + OffsetBytes;
94  }
95 
96  size_t getSize() const { return Size; }
97 
98  uint64_t getLoadAddress() const { return LoadAddress; }
99  void setLoadAddress(uint64_t LA) { LoadAddress = LA; }
100 
101  /// \brief Return the load address of this section with an offset.
102  uint64_t getLoadAddressWithOffset(unsigned OffsetBytes) const {
103  assert(OffsetBytes <= AllocationSize && "Offset out of bounds!");
104  return LoadAddress + OffsetBytes;
105  }
106 
107  uintptr_t getStubOffset() const { return StubOffset; }
108 
109  void advanceStubOffset(unsigned StubSize) {
110  StubOffset += StubSize;
111  assert(StubOffset <= AllocationSize && "Not enough space allocated!");
112  }
113 
114  uintptr_t getObjAddress() const { return ObjAddress; }
115 };
116 
117 /// RelocationEntry - used to represent relocations internally in the dynamic
118 /// linker.
120 public:
121  /// SectionID - the section this relocation points to.
122  unsigned SectionID;
123 
124  /// Offset - offset into the section.
125  uint64_t Offset;
126 
127  /// RelType - relocation type.
129 
130  /// Addend - the relocation addend encoded in the instruction itself. Also
131  /// used to make a relocation section relative instead of symbol relative.
132  int64_t Addend;
133 
134  struct SectionPair {
137  };
138 
139  /// SymOffset - Section offset of the relocation entry's symbol (used for GOT
140  /// lookup).
141  union {
142  uint64_t SymOffset;
144  };
145 
146  /// True if this is a PCRel relocation (MachO specific).
147  bool IsPCRel;
148 
149  /// The size of this relocation (MachO specific).
150  unsigned Size;
151 
152  // COFF specific.
154 
155  RelocationEntry(unsigned id, uint64_t offset, uint32_t type, int64_t addend)
156  : SectionID(id), Offset(offset), RelType(type), Addend(addend),
157  SymOffset(0), IsPCRel(false), Size(0), IsTargetThumbFunc(false) {}
158 
159  RelocationEntry(unsigned id, uint64_t offset, uint32_t type, int64_t addend,
160  uint64_t symoffset)
161  : SectionID(id), Offset(offset), RelType(type), Addend(addend),
162  SymOffset(symoffset), IsPCRel(false), Size(0),
163  IsTargetThumbFunc(false) {}
164 
165  RelocationEntry(unsigned id, uint64_t offset, uint32_t type, int64_t addend,
166  bool IsPCRel, unsigned Size)
167  : SectionID(id), Offset(offset), RelType(type), Addend(addend),
168  SymOffset(0), IsPCRel(IsPCRel), Size(Size), IsTargetThumbFunc(false) {}
169 
170  RelocationEntry(unsigned id, uint64_t offset, uint32_t type, int64_t addend,
171  unsigned SectionA, uint64_t SectionAOffset, unsigned SectionB,
172  uint64_t SectionBOffset, bool IsPCRel, unsigned Size)
173  : SectionID(id), Offset(offset), RelType(type),
174  Addend(SectionAOffset - SectionBOffset + addend), IsPCRel(IsPCRel),
175  Size(Size), IsTargetThumbFunc(false) {
176  Sections.SectionA = SectionA;
177  Sections.SectionB = SectionB;
178  }
179 
180  RelocationEntry(unsigned id, uint64_t offset, uint32_t type, int64_t addend,
181  unsigned SectionA, uint64_t SectionAOffset, unsigned SectionB,
182  uint64_t SectionBOffset, bool IsPCRel, unsigned Size,
183  bool IsTargetThumbFunc)
184  : SectionID(id), Offset(offset), RelType(type),
185  Addend(SectionAOffset - SectionBOffset + addend), IsPCRel(IsPCRel),
186  Size(Size), IsTargetThumbFunc(IsTargetThumbFunc) {
187  Sections.SectionA = SectionA;
188  Sections.SectionB = SectionB;
189  }
190 };
191 
193 public:
194  unsigned SectionID;
195  uint64_t Offset;
196  int64_t Addend;
197  const char *SymbolName;
198  RelocationValueRef() : SectionID(0), Offset(0), Addend(0),
199  SymbolName(nullptr) {}
200 
201  inline bool operator==(const RelocationValueRef &Other) const {
202  return SectionID == Other.SectionID && Offset == Other.Offset &&
203  Addend == Other.Addend && SymbolName == Other.SymbolName;
204  }
205  inline bool operator<(const RelocationValueRef &Other) const {
206  if (SectionID != Other.SectionID)
207  return SectionID < Other.SectionID;
208  if (Offset != Other.Offset)
209  return Offset < Other.Offset;
210  if (Addend != Other.Addend)
211  return Addend < Other.Addend;
212  return SymbolName < Other.SymbolName;
213  }
214 };
215 
216 /// @brief Symbol info for RuntimeDyld.
218 public:
220  : Offset(0), SectionID(0) {}
221 
222  SymbolTableEntry(unsigned SectionID, uint64_t Offset, JITSymbolFlags Flags)
223  : Offset(Offset), SectionID(SectionID), Flags(Flags) {}
224 
225  unsigned getSectionID() const { return SectionID; }
226  uint64_t getOffset() const { return Offset; }
227 
228  JITSymbolFlags getFlags() const { return Flags; }
229 
230 private:
231  uint64_t Offset;
232  unsigned SectionID;
234 };
235 
237 
241 protected:
242  static const unsigned AbsoluteSymbolSection = ~0U;
243 
244  // The MemoryManager to load objects into.
246 
247  // The symbol resolver to use for external symbols.
249 
250  // Attached RuntimeDyldChecker instance. Null if no instance attached.
252 
253  // A list of all sections emitted by the dynamic linker. These sections are
254  // referenced in the code by means of their index in this list - SectionID.
256  SectionList Sections;
257 
258  typedef unsigned SID; // Type for SectionIDs
259 #define RTDYLD_INVALID_SECTION_ID ((RuntimeDyldImpl::SID)(-1))
260 
261  // Keep a map of sections from object file to the SectionID which
262  // references it.
263  typedef std::map<SectionRef, unsigned> ObjSectionToIDMap;
264 
265  // A global symbol table for symbols from all loaded modules.
266  RTDyldSymbolTable GlobalSymbolTable;
267 
268  // Keep a map of common symbols to their info pairs
269  typedef std::vector<SymbolRef> CommonSymbolList;
270 
271  // For each symbol, keep a list of relocations based on it. Anytime
272  // its address is reassigned (the JIT re-compiled the function, e.g.),
273  // the relocations get re-resolved.
274  // The symbol (or section) the relocation is sourced from is the Key
275  // in the relocation list where it's stored.
277  // Relocations to sections already loaded. Indexed by SectionID which is the
278  // source of the address. The target where the address will be written is
279  // SectionID/Offset in the relocation itself.
280  std::unordered_map<unsigned, RelocationList> Relocations;
281 
282  // Relocations to external symbols that are not yet resolved. Symbols are
283  // external when they aren't found in the global symbol table of all loaded
284  // modules. This map is indexed by symbol name.
286 
287 
288  typedef std::map<RelocationValueRef, uintptr_t> StubMap;
289 
295 
296  // True if all sections should be passed to the memory manager, false if only
297  // sections containing relocations should be. Defaults to 'false'.
299 
300  // This mutex prevents simultaneously loading objects from two different
301  // threads. This keeps us from having to protect individual data structures
302  // and guarantees that section allocation requests to the memory manager
303  // won't be interleaved between modules. It is also used in mapSectionAddress
304  // and resolveRelocations to protect write access to internal data structures.
305  //
306  // loadObject may be called on the same thread during the handling of of
307  // processRelocations, and that's OK. The handling of the relocation lists
308  // is written in such a way as to work correctly if new elements are added to
309  // the end of the list while the list is being processed.
311 
312  virtual unsigned getMaxStubSize() = 0;
313  virtual unsigned getStubAlignment() = 0;
314 
315  bool HasError;
316  std::string ErrorStr;
317 
318  uint64_t getSectionLoadAddress(unsigned SectionID) const {
319  return Sections[SectionID].getLoadAddress();
320  }
321 
322  uint8_t *getSectionAddress(unsigned SectionID) const {
323  return Sections[SectionID].getAddress();
324  }
325 
326  void writeInt16BE(uint8_t *Addr, uint16_t Value) {
327  if (IsTargetLittleEndian)
328  sys::swapByteOrder(Value);
329  *Addr = (Value >> 8) & 0xFF;
330  *(Addr + 1) = Value & 0xFF;
331  }
332 
333  void writeInt32BE(uint8_t *Addr, uint32_t Value) {
334  if (IsTargetLittleEndian)
335  sys::swapByteOrder(Value);
336  *Addr = (Value >> 24) & 0xFF;
337  *(Addr + 1) = (Value >> 16) & 0xFF;
338  *(Addr + 2) = (Value >> 8) & 0xFF;
339  *(Addr + 3) = Value & 0xFF;
340  }
341 
342  void writeInt64BE(uint8_t *Addr, uint64_t Value) {
343  if (IsTargetLittleEndian)
344  sys::swapByteOrder(Value);
345  *Addr = (Value >> 56) & 0xFF;
346  *(Addr + 1) = (Value >> 48) & 0xFF;
347  *(Addr + 2) = (Value >> 40) & 0xFF;
348  *(Addr + 3) = (Value >> 32) & 0xFF;
349  *(Addr + 4) = (Value >> 24) & 0xFF;
350  *(Addr + 5) = (Value >> 16) & 0xFF;
351  *(Addr + 6) = (Value >> 8) & 0xFF;
352  *(Addr + 7) = Value & 0xFF;
353  }
354 
355  virtual void setMipsABI(const ObjectFile &Obj) {
356  IsMipsO32ABI = false;
357  IsMipsN32ABI = false;
358  IsMipsN64ABI = false;
359  }
360 
361  /// Endian-aware read Read the least significant Size bytes from Src.
362  uint64_t readBytesUnaligned(uint8_t *Src, unsigned Size) const;
363 
364  /// Endian-aware write. Write the least significant Size bytes from Value to
365  /// Dst.
366  void writeBytesUnaligned(uint64_t Value, uint8_t *Dst, unsigned Size) const;
367 
368  /// \brief Given the common symbols discovered in the object file, emit a
369  /// new section for them and update the symbol mappings in the object and
370  /// symbol table.
371  Error emitCommonSymbols(const ObjectFile &Obj,
372  CommonSymbolList &CommonSymbols);
373 
374  /// \brief Emits section data from the object file to the MemoryManager.
375  /// \param IsCode if it's true then allocateCodeSection() will be
376  /// used for emits, else allocateDataSection() will be used.
377  /// \return SectionID.
378  Expected<unsigned> emitSection(const ObjectFile &Obj,
379  const SectionRef &Section,
380  bool IsCode);
381 
382  /// \brief Find Section in LocalSections. If the secton is not found - emit
383  /// it and store in LocalSections.
384  /// \param IsCode if it's true then allocateCodeSection() will be
385  /// used for emmits, else allocateDataSection() will be used.
386  /// \return SectionID.
387  Expected<unsigned> findOrEmitSection(const ObjectFile &Obj,
388  const SectionRef &Section, bool IsCode,
389  ObjSectionToIDMap &LocalSections);
390 
391  // \brief Add a relocation entry that uses the given section.
392  void addRelocationForSection(const RelocationEntry &RE, unsigned SectionID);
393 
394  // \brief Add a relocation entry that uses the given symbol. This symbol may
395  // be found in the global symbol table, or it may be external.
396  void addRelocationForSymbol(const RelocationEntry &RE, StringRef SymbolName);
397 
398  /// \brief Emits long jump instruction to Addr.
399  /// \return Pointer to the memory area for emitting target address.
400  uint8_t *createStubFunction(uint8_t *Addr, unsigned AbiVariant = 0);
401 
402  /// \brief Resolves relocations from Relocs list with address from Value.
403  void resolveRelocationList(const RelocationList &Relocs, uint64_t Value);
404 
405  /// \brief A object file specific relocation resolver
406  /// \param RE The relocation to be resolved
407  /// \param Value Target symbol address to apply the relocation action
408  virtual void resolveRelocation(const RelocationEntry &RE, uint64_t Value) = 0;
409 
410  /// \brief Parses one or more object file relocations (some object files use
411  /// relocation pairs) and stores it to Relocations or SymbolRelocations
412  /// (this depends on the object file type).
413  /// \return Iterator to the next relocation that needs to be parsed.
415  processRelocationRef(unsigned SectionID, relocation_iterator RelI,
416  const ObjectFile &Obj, ObjSectionToIDMap &ObjSectionToID,
417  StubMap &Stubs) = 0;
418 
419  /// \brief Resolve relocations to external symbols.
420  Error resolveExternalSymbols();
421 
422  // \brief Compute an upper bound of the memory that is required to load all
423  // sections
424  Error computeTotalAllocSize(const ObjectFile &Obj,
425  uint64_t &CodeSize, uint32_t &CodeAlign,
426  uint64_t &RODataSize, uint32_t &RODataAlign,
427  uint64_t &RWDataSize, uint32_t &RWDataAlign);
428 
429  // \brief Compute GOT size
430  unsigned computeGOTSize(const ObjectFile &Obj);
431 
432  // \brief Compute the stub buffer size required for a section
433  unsigned computeSectionStubBufSize(const ObjectFile &Obj,
434  const SectionRef &Section);
435 
436  // \brief Implementation of the generic part of the loadObject algorithm.
437  Expected<ObjSectionToIDMap> loadObjectImpl(const object::ObjectFile &Obj);
438 
439  // \brief Return size of Global Offset Table (GOT) entry
440  virtual size_t getGOTEntrySize() { return 0; }
441 
442  // \brief Return true if the relocation R may require allocating a GOT entry.
443  virtual bool relocationNeedsGot(const RelocationRef &R) const {
444  return false;
445  }
446 
447  // \brief Return true if the relocation R may require allocating a stub.
448  virtual bool relocationNeedsStub(const RelocationRef &R) const {
449  return true; // Conservative answer
450  }
451 
452 public:
454  JITSymbolResolver &Resolver)
455  : MemMgr(MemMgr), Resolver(Resolver), Checker(nullptr),
456  ProcessAllSections(false), HasError(false) {
457  }
458 
459  virtual ~RuntimeDyldImpl();
460 
461  void setProcessAllSections(bool ProcessAllSections) {
462  this->ProcessAllSections = ProcessAllSections;
463  }
464 
466  this->Checker = Checker;
467  }
468 
469  virtual std::unique_ptr<RuntimeDyld::LoadedObjectInfo>
470  loadObject(const object::ObjectFile &Obj) = 0;
471 
473  // FIXME: Just look up as a function for now. Overly simple of course.
474  // Work in progress.
475  RTDyldSymbolTable::const_iterator pos = GlobalSymbolTable.find(Name);
476  if (pos == GlobalSymbolTable.end())
477  return nullptr;
478  const auto &SymInfo = pos->second;
479  // Absolute symbols do not have a local address.
480  if (SymInfo.getSectionID() == AbsoluteSymbolSection)
481  return nullptr;
482  return getSectionAddress(SymInfo.getSectionID()) + SymInfo.getOffset();
483  }
484 
486  // FIXME: Just look up as a function for now. Overly simple of course.
487  // Work in progress.
488  RTDyldSymbolTable::const_iterator pos = GlobalSymbolTable.find(Name);
489  if (pos == GlobalSymbolTable.end())
490  return nullptr;
491  const auto &SymEntry = pos->second;
492  uint64_t SectionAddr = 0;
493  if (SymEntry.getSectionID() != AbsoluteSymbolSection)
494  SectionAddr = getSectionLoadAddress(SymEntry.getSectionID());
495  uint64_t TargetAddr = SectionAddr + SymEntry.getOffset();
496  return JITEvaluatedSymbol(TargetAddr, SymEntry.getFlags());
497  }
498 
499  void resolveRelocations();
500 
501  void reassignSectionAddress(unsigned SectionID, uint64_t Addr);
502 
503  void mapSectionAddress(const void *LocalAddress, uint64_t TargetAddress);
504 
505  // Is the linker in an error state?
506  bool hasError() { return HasError; }
507 
508  // Mark the error condition as handled and continue.
509  void clearError() { HasError = false; }
510 
511  // Get the error message.
512  StringRef getErrorString() { return ErrorStr; }
513 
514  virtual bool isCompatibleFile(const ObjectFile &Obj) const = 0;
515 
516  virtual void registerEHFrames();
517 
518  void deregisterEHFrames();
519 
520  virtual Error finalizeLoad(const ObjectFile &ObjImg,
521  ObjSectionToIDMap &SectionMap) {
522  return Error::success();
523  }
524 };
525 
526 } // end namespace llvm
527 
528 #endif
Information about the loaded object.
Definition: RuntimeDyld.h:69
RelocationEntry - used to represent relocations internally in the dynamic linker. ...
JITEvaluatedSymbol getSymbol(StringRef Name) const
uint8_t * getSymbolLocalAddress(StringRef Name) const
void swapByteOrder(T &Value)
virtual void setMipsABI(const ObjectFile &Obj)
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
void writeInt16BE(uint8_t *Addr, uint16_t Value)
uint64_t getLoadAddressWithOffset(unsigned OffsetBytes) const
Return the load address of this section with an offset.
bool operator==(const RelocationValueRef &Other) const
RuntimeDyld::MemoryManager & MemMgr
RuntimeDyldImpl(RuntimeDyld::MemoryManager &MemMgr, JITSymbolResolver &Resolver)
iterator find(StringRef Key)
Definition: StringMap.h:337
This class is the base class for all object file types.
Definition: ObjectFile.h:189
RuntimeDyldCheckerImpl * Checker
RelocationEntry(unsigned id, uint64_t offset, uint32_t type, int64_t addend, uint64_t symoffset)
uint8_t * getAddress() const
JITSymbolFlags getFlags() const
bool IsPCRel
True if this is a PCRel relocation (MachO specific).
SectionEntry(StringRef name, uint8_t *address, size_t size, size_t allocationSize, uintptr_t objAddress)
unsigned SectionID
SectionID - the section this relocation points to.
virtual bool relocationNeedsStub(const RelocationRef &R) const
Twine - A lightweight data structure for efficiently representing the concatenation of temporary valu...
Definition: Twine.h:81
This is a value type class that represents a single relocation in the list of relocations in the obje...
Definition: ObjectFile.h:52
std::map< RelocationValueRef, uintptr_t > StubMap
Tagged union holding either a T or a Error.
Definition: CachePruning.h:23
virtual size_t getGOTEntrySize()
virtual Error finalizeLoad(const ObjectFile &ObjImg, ObjSectionToIDMap &SectionMap)
void setLoadAddress(uint64_t LA)
const char * Name
RelocationEntry(unsigned id, uint64_t offset, uint32_t type, int64_t addend)
void setRuntimeDyldChecker(RuntimeDyldCheckerImpl *Checker)
virtual bool relocationNeedsGot(const RelocationRef &R) const
SmallVector< SectionEntry, 64 > SectionList
RelocationEntry(unsigned id, uint64_t offset, uint32_t type, int64_t addend, unsigned SectionA, uint64_t SectionAOffset, unsigned SectionB, uint64_t SectionBOffset, bool IsPCRel, unsigned Size, bool IsTargetThumbFunc)
Flags for symbols in the JIT.
Definition: JITSymbol.h:40
Symbol resolution.
Definition: JITSymbol.h:223
std::vector< SymbolRef > CommonSymbolList
bool operator<(const RelocationValueRef &Other) const
uintptr_t getObjAddress() const
void writeInt32BE(uint8_t *Addr, uint32_t Value)
uint8_t * getSectionAddress(unsigned SectionID) const
uint64_t getOffset() const
static ErrorSuccess success()
Create a success value.
Definition: Error.h:311
unsigned getSectionID() const
StringMap< SymbolTableEntry > RTDyldSymbolTable
int64_t Addend
Addend - the relocation addend encoded in the instruction itself.
uint32_t RelType
RelType - relocation type.
uint64_t getSectionLoadAddress(unsigned SectionID) const
JITSymbolResolver & Resolver
RelocationEntry(unsigned id, uint64_t offset, uint32_t type, int64_t addend, bool IsPCRel, unsigned Size)
Symbol info for RuntimeDyld.
Represents a symbol that has been evaluated to an address already.
Definition: JITSymbol.h:98
uintptr_t getStubOffset() const
void setProcessAllSections(bool ProcessAllSections)
size_t getSize() const
constexpr char Size[]
Key for Kernel::Arg::Metadata::mSize.
Triple::ArchType Arch
static std::vector< std::string > Flags
Definition: FlagsTest.cpp:8
uint64_t Offset
Offset - offset into the section.
std::map< SectionRef, unsigned > ObjSectionToIDMap
uint8_t * getAddressWithOffset(unsigned OffsetBytes) const
Return the address of this section with an offset.
void writeInt64BE(uint8_t *Addr, uint64_t Value)
uint64_t getLoadAddress() const
RelocationEntry(unsigned id, uint64_t offset, uint32_t type, int64_t addend, unsigned SectionA, uint64_t SectionAOffset, unsigned SectionB, uint64_t SectionBOffset, bool IsPCRel, unsigned Size)
StringRef getName() const
SymInfo contains information about symbol: it&#39;s address and section index which is -1LL for absolute ...
SectionEntry - represents a section emitted into memory by the dynamic linker.
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
SymbolTableEntry(unsigned SectionID, uint64_t Offset, JITSymbolFlags Flags)
LLVM Value Representation.
Definition: Value.h:73
static const char * name
RTDyldSymbolTable GlobalSymbolTable
Lightweight error class with error context and mandatory checking.
Definition: Error.h:156
std::unordered_map< unsigned, RelocationList > Relocations
unsigned Size
The size of this relocation (MachO specific).
void advanceStubOffset(unsigned StubSize)
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:49
iterator end()
Definition: StringMap.h:322
StringMap< RelocationList > ExternalSymbolRelocations
SmallVector< RelocationEntry, 64 > RelocationList
This is a value type class that represents a single section in the list of sections in the object fil...
Definition: ObjectFile.h:81