LLVM  9.0.0svn
RuntimeDyldELF.cpp
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1 //===-- RuntimeDyldELF.cpp - Run-time dynamic linker for MC-JIT -*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // Implementation of ELF support for the MC-JIT runtime dynamic linker.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "RuntimeDyldELF.h"
14 #include "RuntimeDyldCheckerImpl.h"
16 #include "llvm/ADT/STLExtras.h"
17 #include "llvm/ADT/StringRef.h"
18 #include "llvm/ADT/Triple.h"
19 #include "llvm/BinaryFormat/ELF.h"
21 #include "llvm/Object/ObjectFile.h"
22 #include "llvm/Support/Endian.h"
24 
25 using namespace llvm;
26 using namespace llvm::object;
27 using namespace llvm::support::endian;
28 
29 #define DEBUG_TYPE "dyld"
30 
31 static void or32le(void *P, int32_t V) { write32le(P, read32le(P) | V); }
32 
33 static void or32AArch64Imm(void *L, uint64_t Imm) {
34  or32le(L, (Imm & 0xFFF) << 10);
35 }
36 
37 template <class T> static void write(bool isBE, void *P, T V) {
38  isBE ? write<T, support::big>(P, V) : write<T, support::little>(P, V);
39 }
40 
41 static void write32AArch64Addr(void *L, uint64_t Imm) {
42  uint32_t ImmLo = (Imm & 0x3) << 29;
43  uint32_t ImmHi = (Imm & 0x1FFFFC) << 3;
44  uint64_t Mask = (0x3 << 29) | (0x1FFFFC << 3);
45  write32le(L, (read32le(L) & ~Mask) | ImmLo | ImmHi);
46 }
47 
48 // Return the bits [Start, End] from Val shifted Start bits.
49 // For instance, getBits(0xF0, 4, 8) returns 0xF.
50 static uint64_t getBits(uint64_t Val, int Start, int End) {
51  uint64_t Mask = ((uint64_t)1 << (End + 1 - Start)) - 1;
52  return (Val >> Start) & Mask;
53 }
54 
55 namespace {
56 
57 template <class ELFT> class DyldELFObject : public ELFObjectFile<ELFT> {
59 
60  typedef Elf_Shdr_Impl<ELFT> Elf_Shdr;
61  typedef Elf_Sym_Impl<ELFT> Elf_Sym;
62  typedef Elf_Rel_Impl<ELFT, false> Elf_Rel;
63  typedef Elf_Rel_Impl<ELFT, true> Elf_Rela;
64 
65  typedef Elf_Ehdr_Impl<ELFT> Elf_Ehdr;
66 
67  typedef typename ELFT::uint addr_type;
68 
69  DyldELFObject(ELFObjectFile<ELFT> &&Obj);
70 
71 public:
73  create(MemoryBufferRef Wrapper);
74 
75  void updateSectionAddress(const SectionRef &Sec, uint64_t Addr);
76 
77  void updateSymbolAddress(const SymbolRef &SymRef, uint64_t Addr);
78 
79  // Methods for type inquiry through isa, cast and dyn_cast
80  static bool classof(const Binary *v) {
81  return (isa<ELFObjectFile<ELFT>>(v) &&
82  classof(cast<ELFObjectFile<ELFT>>(v)));
83  }
84  static bool classof(const ELFObjectFile<ELFT> *v) {
85  return v->isDyldType();
86  }
87 };
88 
89 
90 
91 // The MemoryBuffer passed into this constructor is just a wrapper around the
92 // actual memory. Ultimately, the Binary parent class will take ownership of
93 // this MemoryBuffer object but not the underlying memory.
94 template <class ELFT>
95 DyldELFObject<ELFT>::DyldELFObject(ELFObjectFile<ELFT> &&Obj)
96  : ELFObjectFile<ELFT>(std::move(Obj)) {
97  this->isDyldELFObject = true;
98 }
99 
100 template <class ELFT>
102 DyldELFObject<ELFT>::create(MemoryBufferRef Wrapper) {
103  auto Obj = ELFObjectFile<ELFT>::create(Wrapper);
104  if (auto E = Obj.takeError())
105  return std::move(E);
106  std::unique_ptr<DyldELFObject<ELFT>> Ret(
107  new DyldELFObject<ELFT>(std::move(*Obj)));
108  return std::move(Ret);
109 }
110 
111 template <class ELFT>
112 void DyldELFObject<ELFT>::updateSectionAddress(const SectionRef &Sec,
113  uint64_t Addr) {
114  DataRefImpl ShdrRef = Sec.getRawDataRefImpl();
115  Elf_Shdr *shdr =
116  const_cast<Elf_Shdr *>(reinterpret_cast<const Elf_Shdr *>(ShdrRef.p));
117 
118  // This assumes the address passed in matches the target address bitness
119  // The template-based type cast handles everything else.
120  shdr->sh_addr = static_cast<addr_type>(Addr);
121 }
122 
123 template <class ELFT>
124 void DyldELFObject<ELFT>::updateSymbolAddress(const SymbolRef &SymRef,
125  uint64_t Addr) {
126 
127  Elf_Sym *sym = const_cast<Elf_Sym *>(
129 
130  // This assumes the address passed in matches the target address bitness
131  // The template-based type cast handles everything else.
132  sym->st_value = static_cast<addr_type>(Addr);
133 }
134 
135 class LoadedELFObjectInfo final
136  : public LoadedObjectInfoHelper<LoadedELFObjectInfo,
137  RuntimeDyld::LoadedObjectInfo> {
138 public:
139  LoadedELFObjectInfo(RuntimeDyldImpl &RTDyld, ObjSectionToIDMap ObjSecToIDMap)
140  : LoadedObjectInfoHelper(RTDyld, std::move(ObjSecToIDMap)) {}
141 
143  getObjectForDebug(const ObjectFile &Obj) const override;
144 };
145 
146 template <typename ELFT>
148 createRTDyldELFObject(MemoryBufferRef Buffer, const ObjectFile &SourceObject,
149  const LoadedELFObjectInfo &L) {
150  typedef typename ELFT::Shdr Elf_Shdr;
151  typedef typename ELFT::uint addr_type;
152 
154  DyldELFObject<ELFT>::create(Buffer);
155  if (Error E = ObjOrErr.takeError())
156  return std::move(E);
157 
158  std::unique_ptr<DyldELFObject<ELFT>> Obj = std::move(*ObjOrErr);
159 
160  // Iterate over all sections in the object.
161  auto SI = SourceObject.section_begin();
162  for (const auto &Sec : Obj->sections()) {
164  Sec.getName(SectionName);
165  if (SectionName != "") {
166  DataRefImpl ShdrRef = Sec.getRawDataRefImpl();
167  Elf_Shdr *shdr = const_cast<Elf_Shdr *>(
168  reinterpret_cast<const Elf_Shdr *>(ShdrRef.p));
169 
170  if (uint64_t SecLoadAddr = L.getSectionLoadAddress(*SI)) {
171  // This assumes that the address passed in matches the target address
172  // bitness. The template-based type cast handles everything else.
173  shdr->sh_addr = static_cast<addr_type>(SecLoadAddr);
174  }
175  }
176  ++SI;
177  }
178 
179  return std::move(Obj);
180 }
181 
183 createELFDebugObject(const ObjectFile &Obj, const LoadedELFObjectInfo &L) {
184  assert(Obj.isELF() && "Not an ELF object file.");
185 
186  std::unique_ptr<MemoryBuffer> Buffer =
188 
189  Expected<std::unique_ptr<ObjectFile>> DebugObj(nullptr);
190  handleAllErrors(DebugObj.takeError());
191  if (Obj.getBytesInAddress() == 4 && Obj.isLittleEndian())
192  DebugObj =
193  createRTDyldELFObject<ELF32LE>(Buffer->getMemBufferRef(), Obj, L);
194  else if (Obj.getBytesInAddress() == 4 && !Obj.isLittleEndian())
195  DebugObj =
196  createRTDyldELFObject<ELF32BE>(Buffer->getMemBufferRef(), Obj, L);
197  else if (Obj.getBytesInAddress() == 8 && !Obj.isLittleEndian())
198  DebugObj =
199  createRTDyldELFObject<ELF64BE>(Buffer->getMemBufferRef(), Obj, L);
200  else if (Obj.getBytesInAddress() == 8 && Obj.isLittleEndian())
201  DebugObj =
202  createRTDyldELFObject<ELF64LE>(Buffer->getMemBufferRef(), Obj, L);
203  else
204  llvm_unreachable("Unexpected ELF format");
205 
206  handleAllErrors(DebugObj.takeError());
207  return OwningBinary<ObjectFile>(std::move(*DebugObj), std::move(Buffer));
208 }
209 
211 LoadedELFObjectInfo::getObjectForDebug(const ObjectFile &Obj) const {
212  return createELFDebugObject(Obj, *this);
213 }
214 
215 } // anonymous namespace
216 
217 namespace llvm {
218 
221  : RuntimeDyldImpl(MemMgr, Resolver), GOTSectionID(0), CurrentGOTIndex(0) {}
223 
225  for (int i = 0, e = UnregisteredEHFrameSections.size(); i != e; ++i) {
226  SID EHFrameSID = UnregisteredEHFrameSections[i];
227  uint8_t *EHFrameAddr = Sections[EHFrameSID].getAddress();
228  uint64_t EHFrameLoadAddr = Sections[EHFrameSID].getLoadAddress();
229  size_t EHFrameSize = Sections[EHFrameSID].getSize();
230  MemMgr.registerEHFrames(EHFrameAddr, EHFrameLoadAddr, EHFrameSize);
231  }
232  UnregisteredEHFrameSections.clear();
233 }
234 
235 std::unique_ptr<RuntimeDyldELF>
239  switch (Arch) {
240  default:
241  return make_unique<RuntimeDyldELF>(MemMgr, Resolver);
242  case Triple::mips:
243  case Triple::mipsel:
244  case Triple::mips64:
245  case Triple::mips64el:
246  return make_unique<RuntimeDyldELFMips>(MemMgr, Resolver);
247  }
248 }
249 
250 std::unique_ptr<RuntimeDyld::LoadedObjectInfo>
252  if (auto ObjSectionToIDOrErr = loadObjectImpl(O))
253  return llvm::make_unique<LoadedELFObjectInfo>(*this, *ObjSectionToIDOrErr);
254  else {
255  HasError = true;
256  raw_string_ostream ErrStream(ErrorStr);
257  logAllUnhandledErrors(ObjSectionToIDOrErr.takeError(), ErrStream);
258  return nullptr;
259  }
260 }
261 
262 void RuntimeDyldELF::resolveX86_64Relocation(const SectionEntry &Section,
263  uint64_t Offset, uint64_t Value,
264  uint32_t Type, int64_t Addend,
265  uint64_t SymOffset) {
266  switch (Type) {
267  default:
268  llvm_unreachable("Relocation type not implemented yet!");
269  break;
270  case ELF::R_X86_64_NONE:
271  break;
272  case ELF::R_X86_64_64: {
274  Value + Addend;
275  LLVM_DEBUG(dbgs() << "Writing " << format("%p", (Value + Addend)) << " at "
276  << format("%p\n", Section.getAddressWithOffset(Offset)));
277  break;
278  }
279  case ELF::R_X86_64_32:
280  case ELF::R_X86_64_32S: {
281  Value += Addend;
282  assert((Type == ELF::R_X86_64_32 && (Value <= UINT32_MAX)) ||
283  (Type == ELF::R_X86_64_32S &&
284  ((int64_t)Value <= INT32_MAX && (int64_t)Value >= INT32_MIN)));
285  uint32_t TruncatedAddr = (Value & 0xFFFFFFFF);
287  TruncatedAddr;
288  LLVM_DEBUG(dbgs() << "Writing " << format("%p", TruncatedAddr) << " at "
289  << format("%p\n", Section.getAddressWithOffset(Offset)));
290  break;
291  }
292  case ELF::R_X86_64_PC8: {
293  uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
294  int64_t RealOffset = Value + Addend - FinalAddress;
295  assert(isInt<8>(RealOffset));
296  int8_t TruncOffset = (RealOffset & 0xFF);
297  Section.getAddress()[Offset] = TruncOffset;
298  break;
299  }
300  case ELF::R_X86_64_PC32: {
301  uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
302  int64_t RealOffset = Value + Addend - FinalAddress;
303  assert(isInt<32>(RealOffset));
304  int32_t TruncOffset = (RealOffset & 0xFFFFFFFF);
306  TruncOffset;
307  break;
308  }
309  case ELF::R_X86_64_PC64: {
310  uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
311  int64_t RealOffset = Value + Addend - FinalAddress;
313  RealOffset;
314  LLVM_DEBUG(dbgs() << "Writing " << format("%p", RealOffset) << " at "
315  << format("%p\n", FinalAddress));
316  break;
317  }
318  case ELF::R_X86_64_GOTOFF64: {
319  // Compute Value - GOTBase.
320  uint64_t GOTBase = 0;
321  for (const auto &Section : Sections) {
322  if (Section.getName() == ".got") {
323  GOTBase = Section.getLoadAddressWithOffset(0);
324  break;
325  }
326  }
327  assert(GOTBase != 0 && "missing GOT");
328  int64_t GOTOffset = Value - GOTBase + Addend;
329  support::ulittle64_t::ref(Section.getAddressWithOffset(Offset)) = GOTOffset;
330  break;
331  }
332  }
333 }
334 
335 void RuntimeDyldELF::resolveX86Relocation(const SectionEntry &Section,
336  uint64_t Offset, uint32_t Value,
337  uint32_t Type, int32_t Addend) {
338  switch (Type) {
339  case ELF::R_386_32: {
341  Value + Addend;
342  break;
343  }
344  // Handle R_386_PLT32 like R_386_PC32 since it should be able to
345  // reach any 32 bit address.
346  case ELF::R_386_PLT32:
347  case ELF::R_386_PC32: {
348  uint32_t FinalAddress =
349  Section.getLoadAddressWithOffset(Offset) & 0xFFFFFFFF;
350  uint32_t RealOffset = Value + Addend - FinalAddress;
352  RealOffset;
353  break;
354  }
355  default:
356  // There are other relocation types, but it appears these are the
357  // only ones currently used by the LLVM ELF object writer
358  llvm_unreachable("Relocation type not implemented yet!");
359  break;
360  }
361 }
362 
363 void RuntimeDyldELF::resolveAArch64Relocation(const SectionEntry &Section,
364  uint64_t Offset, uint64_t Value,
365  uint32_t Type, int64_t Addend) {
366  uint32_t *TargetPtr =
367  reinterpret_cast<uint32_t *>(Section.getAddressWithOffset(Offset));
368  uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
369  // Data should use target endian. Code should always use little endian.
370  bool isBE = Arch == Triple::aarch64_be;
371 
372  LLVM_DEBUG(dbgs() << "resolveAArch64Relocation, LocalAddress: 0x"
373  << format("%llx", Section.getAddressWithOffset(Offset))
374  << " FinalAddress: 0x" << format("%llx", FinalAddress)
375  << " Value: 0x" << format("%llx", Value) << " Type: 0x"
376  << format("%x", Type) << " Addend: 0x"
377  << format("%llx", Addend) << "\n");
378 
379  switch (Type) {
380  default:
381  llvm_unreachable("Relocation type not implemented yet!");
382  break;
383  case ELF::R_AARCH64_ABS16: {
384  uint64_t Result = Value + Addend;
385  assert(static_cast<int64_t>(Result) >= INT16_MIN && Result < UINT16_MAX);
386  write(isBE, TargetPtr, static_cast<uint16_t>(Result & 0xffffU));
387  break;
388  }
389  case ELF::R_AARCH64_ABS32: {
390  uint64_t Result = Value + Addend;
391  assert(static_cast<int64_t>(Result) >= INT32_MIN && Result < UINT32_MAX);
392  write(isBE, TargetPtr, static_cast<uint32_t>(Result & 0xffffffffU));
393  break;
394  }
395  case ELF::R_AARCH64_ABS64:
396  write(isBE, TargetPtr, Value + Addend);
397  break;
398  case ELF::R_AARCH64_PREL32: {
399  uint64_t Result = Value + Addend - FinalAddress;
400  assert(static_cast<int64_t>(Result) >= INT32_MIN &&
401  static_cast<int64_t>(Result) <= UINT32_MAX);
402  write(isBE, TargetPtr, static_cast<uint32_t>(Result & 0xffffffffU));
403  break;
404  }
405  case ELF::R_AARCH64_PREL64:
406  write(isBE, TargetPtr, Value + Addend - FinalAddress);
407  break;
408  case ELF::R_AARCH64_CALL26: // fallthrough
409  case ELF::R_AARCH64_JUMP26: {
410  // Operation: S+A-P. Set Call or B immediate value to bits fff_fffc of the
411  // calculation.
412  uint64_t BranchImm = Value + Addend - FinalAddress;
413 
414  // "Check that -2^27 <= result < 2^27".
415  assert(isInt<28>(BranchImm));
416  or32le(TargetPtr, (BranchImm & 0x0FFFFFFC) >> 2);
417  break;
418  }
419  case ELF::R_AARCH64_MOVW_UABS_G3:
420  or32le(TargetPtr, ((Value + Addend) & 0xFFFF000000000000) >> 43);
421  break;
422  case ELF::R_AARCH64_MOVW_UABS_G2_NC:
423  or32le(TargetPtr, ((Value + Addend) & 0xFFFF00000000) >> 27);
424  break;
425  case ELF::R_AARCH64_MOVW_UABS_G1_NC:
426  or32le(TargetPtr, ((Value + Addend) & 0xFFFF0000) >> 11);
427  break;
428  case ELF::R_AARCH64_MOVW_UABS_G0_NC:
429  or32le(TargetPtr, ((Value + Addend) & 0xFFFF) << 5);
430  break;
431  case ELF::R_AARCH64_ADR_PREL_PG_HI21: {
432  // Operation: Page(S+A) - Page(P)
433  uint64_t Result =
434  ((Value + Addend) & ~0xfffULL) - (FinalAddress & ~0xfffULL);
435 
436  // Check that -2^32 <= X < 2^32
437  assert(isInt<33>(Result) && "overflow check failed for relocation");
438 
439  // Immediate goes in bits 30:29 + 5:23 of ADRP instruction, taken
440  // from bits 32:12 of X.
441  write32AArch64Addr(TargetPtr, Result >> 12);
442  break;
443  }
444  case ELF::R_AARCH64_ADD_ABS_LO12_NC:
445  // Operation: S + A
446  // Immediate goes in bits 21:10 of LD/ST instruction, taken
447  // from bits 11:0 of X
448  or32AArch64Imm(TargetPtr, Value + Addend);
449  break;
450  case ELF::R_AARCH64_LDST8_ABS_LO12_NC:
451  // Operation: S + A
452  // Immediate goes in bits 21:10 of LD/ST instruction, taken
453  // from bits 11:0 of X
454  or32AArch64Imm(TargetPtr, getBits(Value + Addend, 0, 11));
455  break;
456  case ELF::R_AARCH64_LDST16_ABS_LO12_NC:
457  // Operation: S + A
458  // Immediate goes in bits 21:10 of LD/ST instruction, taken
459  // from bits 11:1 of X
460  or32AArch64Imm(TargetPtr, getBits(Value + Addend, 1, 11));
461  break;
462  case ELF::R_AARCH64_LDST32_ABS_LO12_NC:
463  // Operation: S + A
464  // Immediate goes in bits 21:10 of LD/ST instruction, taken
465  // from bits 11:2 of X
466  or32AArch64Imm(TargetPtr, getBits(Value + Addend, 2, 11));
467  break;
468  case ELF::R_AARCH64_LDST64_ABS_LO12_NC:
469  // Operation: S + A
470  // Immediate goes in bits 21:10 of LD/ST instruction, taken
471  // from bits 11:3 of X
472  or32AArch64Imm(TargetPtr, getBits(Value + Addend, 3, 11));
473  break;
474  case ELF::R_AARCH64_LDST128_ABS_LO12_NC:
475  // Operation: S + A
476  // Immediate goes in bits 21:10 of LD/ST instruction, taken
477  // from bits 11:4 of X
478  or32AArch64Imm(TargetPtr, getBits(Value + Addend, 4, 11));
479  break;
480  }
481 }
482 
483 void RuntimeDyldELF::resolveARMRelocation(const SectionEntry &Section,
484  uint64_t Offset, uint32_t Value,
485  uint32_t Type, int32_t Addend) {
486  // TODO: Add Thumb relocations.
487  uint32_t *TargetPtr =
488  reinterpret_cast<uint32_t *>(Section.getAddressWithOffset(Offset));
489  uint32_t FinalAddress = Section.getLoadAddressWithOffset(Offset) & 0xFFFFFFFF;
490  Value += Addend;
491 
492  LLVM_DEBUG(dbgs() << "resolveARMRelocation, LocalAddress: "
493  << Section.getAddressWithOffset(Offset)
494  << " FinalAddress: " << format("%p", FinalAddress)
495  << " Value: " << format("%x", Value)
496  << " Type: " << format("%x", Type)
497  << " Addend: " << format("%x", Addend) << "\n");
498 
499  switch (Type) {
500  default:
501  llvm_unreachable("Not implemented relocation type!");
502 
503  case ELF::R_ARM_NONE:
504  break;
505  // Write a 31bit signed offset
506  case ELF::R_ARM_PREL31:
507  support::ulittle32_t::ref{TargetPtr} =
508  (support::ulittle32_t::ref{TargetPtr} & 0x80000000) |
509  ((Value - FinalAddress) & ~0x80000000);
510  break;
511  case ELF::R_ARM_TARGET1:
512  case ELF::R_ARM_ABS32:
513  support::ulittle32_t::ref{TargetPtr} = Value;
514  break;
515  // Write first 16 bit of 32 bit value to the mov instruction.
516  // Last 4 bit should be shifted.
517  case ELF::R_ARM_MOVW_ABS_NC:
518  case ELF::R_ARM_MOVT_ABS:
519  if (Type == ELF::R_ARM_MOVW_ABS_NC)
520  Value = Value & 0xFFFF;
521  else if (Type == ELF::R_ARM_MOVT_ABS)
522  Value = (Value >> 16) & 0xFFFF;
523  support::ulittle32_t::ref{TargetPtr} =
524  (support::ulittle32_t::ref{TargetPtr} & ~0x000F0FFF) | (Value & 0xFFF) |
525  (((Value >> 12) & 0xF) << 16);
526  break;
527  // Write 24 bit relative value to the branch instruction.
528  case ELF::R_ARM_PC24: // Fall through.
529  case ELF::R_ARM_CALL: // Fall through.
530  case ELF::R_ARM_JUMP24:
531  int32_t RelValue = static_cast<int32_t>(Value - FinalAddress - 8);
532  RelValue = (RelValue & 0x03FFFFFC) >> 2;
533  assert((support::ulittle32_t::ref{TargetPtr} & 0xFFFFFF) == 0xFFFFFE);
534  support::ulittle32_t::ref{TargetPtr} =
535  (support::ulittle32_t::ref{TargetPtr} & 0xFF000000) | RelValue;
536  break;
537  }
538 }
539 
540 void RuntimeDyldELF::setMipsABI(const ObjectFile &Obj) {
541  if (Arch == Triple::UnknownArch ||
542  !StringRef(Triple::getArchTypePrefix(Arch)).equals("mips")) {
543  IsMipsO32ABI = false;
544  IsMipsN32ABI = false;
545  IsMipsN64ABI = false;
546  return;
547  }
548  if (auto *E = dyn_cast<ELFObjectFileBase>(&Obj)) {
549  unsigned AbiVariant = E->getPlatformFlags();
550  IsMipsO32ABI = AbiVariant & ELF::EF_MIPS_ABI_O32;
551  IsMipsN32ABI = AbiVariant & ELF::EF_MIPS_ABI2;
552  }
553  IsMipsN64ABI = Obj.getFileFormatName().equals("ELF64-mips");
554 }
555 
556 // Return the .TOC. section and offset.
557 Error RuntimeDyldELF::findPPC64TOCSection(const ELFObjectFileBase &Obj,
558  ObjSectionToIDMap &LocalSections,
559  RelocationValueRef &Rel) {
560  // Set a default SectionID in case we do not find a TOC section below.
561  // This may happen for references to TOC base base (sym@toc, .odp
562  // relocation) without a .toc directive. In this case just use the
563  // first section (which is usually the .odp) since the code won't
564  // reference the .toc base directly.
565  Rel.SymbolName = nullptr;
566  Rel.SectionID = 0;
567 
568  // The TOC consists of sections .got, .toc, .tocbss, .plt in that
569  // order. The TOC starts where the first of these sections starts.
570  for (auto &Section: Obj.sections()) {
572  if (auto EC = Section.getName(SectionName))
573  return errorCodeToError(EC);
574 
575  if (SectionName == ".got"
576  || SectionName == ".toc"
577  || SectionName == ".tocbss"
578  || SectionName == ".plt") {
579  if (auto SectionIDOrErr =
580  findOrEmitSection(Obj, Section, false, LocalSections))
581  Rel.SectionID = *SectionIDOrErr;
582  else
583  return SectionIDOrErr.takeError();
584  break;
585  }
586  }
587 
588  // Per the ppc64-elf-linux ABI, The TOC base is TOC value plus 0x8000
589  // thus permitting a full 64 Kbytes segment.
590  Rel.Addend = 0x8000;
591 
592  return Error::success();
593 }
594 
595 // Returns the sections and offset associated with the ODP entry referenced
596 // by Symbol.
597 Error RuntimeDyldELF::findOPDEntrySection(const ELFObjectFileBase &Obj,
598  ObjSectionToIDMap &LocalSections,
599  RelocationValueRef &Rel) {
600  // Get the ELF symbol value (st_value) to compare with Relocation offset in
601  // .opd entries
602  for (section_iterator si = Obj.section_begin(), se = Obj.section_end();
603  si != se; ++si) {
604  section_iterator RelSecI = si->getRelocatedSection();
605  if (RelSecI == Obj.section_end())
606  continue;
607 
608  StringRef RelSectionName;
609  if (auto EC = RelSecI->getName(RelSectionName))
610  return errorCodeToError(EC);
611 
612  if (RelSectionName != ".opd")
613  continue;
614 
615  for (elf_relocation_iterator i = si->relocation_begin(),
616  e = si->relocation_end();
617  i != e;) {
618  // The R_PPC64_ADDR64 relocation indicates the first field
619  // of a .opd entry
620  uint64_t TypeFunc = i->getType();
621  if (TypeFunc != ELF::R_PPC64_ADDR64) {
622  ++i;
623  continue;
624  }
625 
626  uint64_t TargetSymbolOffset = i->getOffset();
627  symbol_iterator TargetSymbol = i->getSymbol();
628  int64_t Addend;
629  if (auto AddendOrErr = i->getAddend())
630  Addend = *AddendOrErr;
631  else
632  return AddendOrErr.takeError();
633 
634  ++i;
635  if (i == e)
636  break;
637 
638  // Just check if following relocation is a R_PPC64_TOC
639  uint64_t TypeTOC = i->getType();
640  if (TypeTOC != ELF::R_PPC64_TOC)
641  continue;
642 
643  // Finally compares the Symbol value and the target symbol offset
644  // to check if this .opd entry refers to the symbol the relocation
645  // points to.
646  if (Rel.Addend != (int64_t)TargetSymbolOffset)
647  continue;
648 
649  section_iterator TSI = Obj.section_end();
650  if (auto TSIOrErr = TargetSymbol->getSection())
651  TSI = *TSIOrErr;
652  else
653  return TSIOrErr.takeError();
654  assert(TSI != Obj.section_end() && "TSI should refer to a valid section");
655 
656  bool IsCode = TSI->isText();
657  if (auto SectionIDOrErr = findOrEmitSection(Obj, *TSI, IsCode,
658  LocalSections))
659  Rel.SectionID = *SectionIDOrErr;
660  else
661  return SectionIDOrErr.takeError();
662  Rel.Addend = (intptr_t)Addend;
663  return Error::success();
664  }
665  }
666  llvm_unreachable("Attempting to get address of ODP entry!");
667 }
668 
669 // Relocation masks following the #lo(value), #hi(value), #ha(value),
670 // #higher(value), #highera(value), #highest(value), and #highesta(value)
671 // macros defined in section 4.5.1. Relocation Types of the PPC-elf64abi
672 // document.
673 
674 static inline uint16_t applyPPClo(uint64_t value) { return value & 0xffff; }
675 
676 static inline uint16_t applyPPChi(uint64_t value) {
677  return (value >> 16) & 0xffff;
678 }
679 
680 static inline uint16_t applyPPCha (uint64_t value) {
681  return ((value + 0x8000) >> 16) & 0xffff;
682 }
683 
684 static inline uint16_t applyPPChigher(uint64_t value) {
685  return (value >> 32) & 0xffff;
686 }
687 
688 static inline uint16_t applyPPChighera (uint64_t value) {
689  return ((value + 0x8000) >> 32) & 0xffff;
690 }
691 
692 static inline uint16_t applyPPChighest(uint64_t value) {
693  return (value >> 48) & 0xffff;
694 }
695 
696 static inline uint16_t applyPPChighesta (uint64_t value) {
697  return ((value + 0x8000) >> 48) & 0xffff;
698 }
699 
700 void RuntimeDyldELF::resolvePPC32Relocation(const SectionEntry &Section,
701  uint64_t Offset, uint64_t Value,
702  uint32_t Type, int64_t Addend) {
703  uint8_t *LocalAddress = Section.getAddressWithOffset(Offset);
704  switch (Type) {
705  default:
706  llvm_unreachable("Relocation type not implemented yet!");
707  break;
708  case ELF::R_PPC_ADDR16_LO:
709  writeInt16BE(LocalAddress, applyPPClo(Value + Addend));
710  break;
711  case ELF::R_PPC_ADDR16_HI:
712  writeInt16BE(LocalAddress, applyPPChi(Value + Addend));
713  break;
714  case ELF::R_PPC_ADDR16_HA:
715  writeInt16BE(LocalAddress, applyPPCha(Value + Addend));
716  break;
717  }
718 }
719 
720 void RuntimeDyldELF::resolvePPC64Relocation(const SectionEntry &Section,
721  uint64_t Offset, uint64_t Value,
722  uint32_t Type, int64_t Addend) {
723  uint8_t *LocalAddress = Section.getAddressWithOffset(Offset);
724  switch (Type) {
725  default:
726  llvm_unreachable("Relocation type not implemented yet!");
727  break;
728  case ELF::R_PPC64_ADDR16:
729  writeInt16BE(LocalAddress, applyPPClo(Value + Addend));
730  break;
731  case ELF::R_PPC64_ADDR16_DS:
732  writeInt16BE(LocalAddress, applyPPClo(Value + Addend) & ~3);
733  break;
734  case ELF::R_PPC64_ADDR16_LO:
735  writeInt16BE(LocalAddress, applyPPClo(Value + Addend));
736  break;
737  case ELF::R_PPC64_ADDR16_LO_DS:
738  writeInt16BE(LocalAddress, applyPPClo(Value + Addend) & ~3);
739  break;
740  case ELF::R_PPC64_ADDR16_HI:
741  case ELF::R_PPC64_ADDR16_HIGH:
742  writeInt16BE(LocalAddress, applyPPChi(Value + Addend));
743  break;
744  case ELF::R_PPC64_ADDR16_HA:
745  case ELF::R_PPC64_ADDR16_HIGHA:
746  writeInt16BE(LocalAddress, applyPPCha(Value + Addend));
747  break;
748  case ELF::R_PPC64_ADDR16_HIGHER:
749  writeInt16BE(LocalAddress, applyPPChigher(Value + Addend));
750  break;
751  case ELF::R_PPC64_ADDR16_HIGHERA:
752  writeInt16BE(LocalAddress, applyPPChighera(Value + Addend));
753  break;
754  case ELF::R_PPC64_ADDR16_HIGHEST:
755  writeInt16BE(LocalAddress, applyPPChighest(Value + Addend));
756  break;
757  case ELF::R_PPC64_ADDR16_HIGHESTA:
758  writeInt16BE(LocalAddress, applyPPChighesta(Value + Addend));
759  break;
760  case ELF::R_PPC64_ADDR14: {
761  assert(((Value + Addend) & 3) == 0);
762  // Preserve the AA/LK bits in the branch instruction
763  uint8_t aalk = *(LocalAddress + 3);
764  writeInt16BE(LocalAddress + 2, (aalk & 3) | ((Value + Addend) & 0xfffc));
765  } break;
766  case ELF::R_PPC64_REL16_LO: {
767  uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
768  uint64_t Delta = Value - FinalAddress + Addend;
769  writeInt16BE(LocalAddress, applyPPClo(Delta));
770  } break;
771  case ELF::R_PPC64_REL16_HI: {
772  uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
773  uint64_t Delta = Value - FinalAddress + Addend;
774  writeInt16BE(LocalAddress, applyPPChi(Delta));
775  } break;
776  case ELF::R_PPC64_REL16_HA: {
777  uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
778  uint64_t Delta = Value - FinalAddress + Addend;
779  writeInt16BE(LocalAddress, applyPPCha(Delta));
780  } break;
781  case ELF::R_PPC64_ADDR32: {
782  int64_t Result = static_cast<int64_t>(Value + Addend);
783  if (SignExtend64<32>(Result) != Result)
784  llvm_unreachable("Relocation R_PPC64_ADDR32 overflow");
785  writeInt32BE(LocalAddress, Result);
786  } break;
787  case ELF::R_PPC64_REL24: {
788  uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
789  int64_t delta = static_cast<int64_t>(Value - FinalAddress + Addend);
790  if (SignExtend64<26>(delta) != delta)
791  llvm_unreachable("Relocation R_PPC64_REL24 overflow");
792  // We preserve bits other than LI field, i.e. PO and AA/LK fields.
793  uint32_t Inst = readBytesUnaligned(LocalAddress, 4);
794  writeInt32BE(LocalAddress, (Inst & 0xFC000003) | (delta & 0x03FFFFFC));
795  } break;
796  case ELF::R_PPC64_REL32: {
797  uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
798  int64_t delta = static_cast<int64_t>(Value - FinalAddress + Addend);
799  if (SignExtend64<32>(delta) != delta)
800  llvm_unreachable("Relocation R_PPC64_REL32 overflow");
801  writeInt32BE(LocalAddress, delta);
802  } break;
803  case ELF::R_PPC64_REL64: {
804  uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
805  uint64_t Delta = Value - FinalAddress + Addend;
806  writeInt64BE(LocalAddress, Delta);
807  } break;
808  case ELF::R_PPC64_ADDR64:
809  writeInt64BE(LocalAddress, Value + Addend);
810  break;
811  }
812 }
813 
814 void RuntimeDyldELF::resolveSystemZRelocation(const SectionEntry &Section,
815  uint64_t Offset, uint64_t Value,
816  uint32_t Type, int64_t Addend) {
817  uint8_t *LocalAddress = Section.getAddressWithOffset(Offset);
818  switch (Type) {
819  default:
820  llvm_unreachable("Relocation type not implemented yet!");
821  break;
822  case ELF::R_390_PC16DBL:
823  case ELF::R_390_PLT16DBL: {
824  int64_t Delta = (Value + Addend) - Section.getLoadAddressWithOffset(Offset);
825  assert(int16_t(Delta / 2) * 2 == Delta && "R_390_PC16DBL overflow");
826  writeInt16BE(LocalAddress, Delta / 2);
827  break;
828  }
829  case ELF::R_390_PC32DBL:
830  case ELF::R_390_PLT32DBL: {
831  int64_t Delta = (Value + Addend) - Section.getLoadAddressWithOffset(Offset);
832  assert(int32_t(Delta / 2) * 2 == Delta && "R_390_PC32DBL overflow");
833  writeInt32BE(LocalAddress, Delta / 2);
834  break;
835  }
836  case ELF::R_390_PC16: {
837  int64_t Delta = (Value + Addend) - Section.getLoadAddressWithOffset(Offset);
838  assert(int16_t(Delta) == Delta && "R_390_PC16 overflow");
839  writeInt16BE(LocalAddress, Delta);
840  break;
841  }
842  case ELF::R_390_PC32: {
843  int64_t Delta = (Value + Addend) - Section.getLoadAddressWithOffset(Offset);
844  assert(int32_t(Delta) == Delta && "R_390_PC32 overflow");
845  writeInt32BE(LocalAddress, Delta);
846  break;
847  }
848  case ELF::R_390_PC64: {
849  int64_t Delta = (Value + Addend) - Section.getLoadAddressWithOffset(Offset);
850  writeInt64BE(LocalAddress, Delta);
851  break;
852  }
853  case ELF::R_390_8:
854  *LocalAddress = (uint8_t)(Value + Addend);
855  break;
856  case ELF::R_390_16:
857  writeInt16BE(LocalAddress, Value + Addend);
858  break;
859  case ELF::R_390_32:
860  writeInt32BE(LocalAddress, Value + Addend);
861  break;
862  case ELF::R_390_64:
863  writeInt64BE(LocalAddress, Value + Addend);
864  break;
865  }
866 }
867 
868 void RuntimeDyldELF::resolveBPFRelocation(const SectionEntry &Section,
869  uint64_t Offset, uint64_t Value,
870  uint32_t Type, int64_t Addend) {
871  bool isBE = Arch == Triple::bpfeb;
872 
873  switch (Type) {
874  default:
875  llvm_unreachable("Relocation type not implemented yet!");
876  break;
877  case ELF::R_BPF_NONE:
878  break;
879  case ELF::R_BPF_64_64: {
880  write(isBE, Section.getAddressWithOffset(Offset), Value + Addend);
881  LLVM_DEBUG(dbgs() << "Writing " << format("%p", (Value + Addend)) << " at "
882  << format("%p\n", Section.getAddressWithOffset(Offset)));
883  break;
884  }
885  case ELF::R_BPF_64_32: {
886  Value += Addend;
887  assert(Value <= UINT32_MAX);
888  write(isBE, Section.getAddressWithOffset(Offset), static_cast<uint32_t>(Value));
889  LLVM_DEBUG(dbgs() << "Writing " << format("%p", Value) << " at "
890  << format("%p\n", Section.getAddressWithOffset(Offset)));
891  break;
892  }
893  }
894 }
895 
896 // The target location for the relocation is described by RE.SectionID and
897 // RE.Offset. RE.SectionID can be used to find the SectionEntry. Each
898 // SectionEntry has three members describing its location.
899 // SectionEntry::Address is the address at which the section has been loaded
900 // into memory in the current (host) process. SectionEntry::LoadAddress is the
901 // address that the section will have in the target process.
902 // SectionEntry::ObjAddress is the address of the bits for this section in the
903 // original emitted object image (also in the current address space).
904 //
905 // Relocations will be applied as if the section were loaded at
906 // SectionEntry::LoadAddress, but they will be applied at an address based
907 // on SectionEntry::Address. SectionEntry::ObjAddress will be used to refer to
908 // Target memory contents if they are required for value calculations.
909 //
910 // The Value parameter here is the load address of the symbol for the
911 // relocation to be applied. For relocations which refer to symbols in the
912 // current object Value will be the LoadAddress of the section in which
913 // the symbol resides (RE.Addend provides additional information about the
914 // symbol location). For external symbols, Value will be the address of the
915 // symbol in the target address space.
916 void RuntimeDyldELF::resolveRelocation(const RelocationEntry &RE,
917  uint64_t Value) {
918  const SectionEntry &Section = Sections[RE.SectionID];
919  return resolveRelocation(Section, RE.Offset, Value, RE.RelType, RE.Addend,
920  RE.SymOffset, RE.SectionID);
921 }
922 
923 void RuntimeDyldELF::resolveRelocation(const SectionEntry &Section,
924  uint64_t Offset, uint64_t Value,
925  uint32_t Type, int64_t Addend,
926  uint64_t SymOffset, SID SectionID) {
927  switch (Arch) {
928  case Triple::x86_64:
929  resolveX86_64Relocation(Section, Offset, Value, Type, Addend, SymOffset);
930  break;
931  case Triple::x86:
932  resolveX86Relocation(Section, Offset, (uint32_t)(Value & 0xffffffffL), Type,
933  (uint32_t)(Addend & 0xffffffffL));
934  break;
935  case Triple::aarch64:
936  case Triple::aarch64_be:
937  resolveAArch64Relocation(Section, Offset, Value, Type, Addend);
938  break;
939  case Triple::arm: // Fall through.
940  case Triple::armeb:
941  case Triple::thumb:
942  case Triple::thumbeb:
943  resolveARMRelocation(Section, Offset, (uint32_t)(Value & 0xffffffffL), Type,
944  (uint32_t)(Addend & 0xffffffffL));
945  break;
946  case Triple::ppc:
947  resolvePPC32Relocation(Section, Offset, Value, Type, Addend);
948  break;
949  case Triple::ppc64: // Fall through.
950  case Triple::ppc64le:
951  resolvePPC64Relocation(Section, Offset, Value, Type, Addend);
952  break;
953  case Triple::systemz:
954  resolveSystemZRelocation(Section, Offset, Value, Type, Addend);
955  break;
956  case Triple::bpfel:
957  case Triple::bpfeb:
958  resolveBPFRelocation(Section, Offset, Value, Type, Addend);
959  break;
960  default:
961  llvm_unreachable("Unsupported CPU type!");
962  }
963 }
964 
965 void *RuntimeDyldELF::computePlaceholderAddress(unsigned SectionID, uint64_t Offset) const {
966  return (void *)(Sections[SectionID].getObjAddress() + Offset);
967 }
968 
969 void RuntimeDyldELF::processSimpleRelocation(unsigned SectionID, uint64_t Offset, unsigned RelType, RelocationValueRef Value) {
970  RelocationEntry RE(SectionID, Offset, RelType, Value.Addend, Value.Offset);
971  if (Value.SymbolName)
973  else
975 }
976 
977 uint32_t RuntimeDyldELF::getMatchingLoRelocation(uint32_t RelType,
978  bool IsLocal) const {
979  switch (RelType) {
980  case ELF::R_MICROMIPS_GOT16:
981  if (IsLocal)
982  return ELF::R_MICROMIPS_LO16;
983  break;
984  case ELF::R_MICROMIPS_HI16:
985  return ELF::R_MICROMIPS_LO16;
986  case ELF::R_MIPS_GOT16:
987  if (IsLocal)
988  return ELF::R_MIPS_LO16;
989  break;
990  case ELF::R_MIPS_HI16:
991  return ELF::R_MIPS_LO16;
992  case ELF::R_MIPS_PCHI16:
993  return ELF::R_MIPS_PCLO16;
994  default:
995  break;
996  }
997  return ELF::R_MIPS_NONE;
998 }
999 
1000 // Sometimes we don't need to create thunk for a branch.
1001 // This typically happens when branch target is located
1002 // in the same object file. In such case target is either
1003 // a weak symbol or symbol in a different executable section.
1004 // This function checks if branch target is located in the
1005 // same object file and if distance between source and target
1006 // fits R_AARCH64_CALL26 relocation. If both conditions are
1007 // met, it emits direct jump to the target and returns true.
1008 // Otherwise false is returned and thunk is created.
1009 bool RuntimeDyldELF::resolveAArch64ShortBranch(
1010  unsigned SectionID, relocation_iterator RelI,
1011  const RelocationValueRef &Value) {
1012  uint64_t Address;
1013  if (Value.SymbolName) {
1014  auto Loc = GlobalSymbolTable.find(Value.SymbolName);
1015 
1016  // Don't create direct branch for external symbols.
1017  if (Loc == GlobalSymbolTable.end())
1018  return false;
1019 
1020  const auto &SymInfo = Loc->second;
1021  Address =
1022  uint64_t(Sections[SymInfo.getSectionID()].getLoadAddressWithOffset(
1023  SymInfo.getOffset()));
1024  } else {
1025  Address = uint64_t(Sections[Value.SectionID].getLoadAddress());
1026  }
1027  uint64_t Offset = RelI->getOffset();
1028  uint64_t SourceAddress = Sections[SectionID].getLoadAddressWithOffset(Offset);
1029 
1030  // R_AARCH64_CALL26 requires immediate to be in range -2^27 <= imm < 2^27
1031  // If distance between source and target is out of range then we should
1032  // create thunk.
1033  if (!isInt<28>(Address + Value.Addend - SourceAddress))
1034  return false;
1035 
1036  resolveRelocation(Sections[SectionID], Offset, Address, RelI->getType(),
1037  Value.Addend);
1038 
1039  return true;
1040 }
1041 
1042 void RuntimeDyldELF::resolveAArch64Branch(unsigned SectionID,
1043  const RelocationValueRef &Value,
1044  relocation_iterator RelI,
1045  StubMap &Stubs) {
1046 
1047  LLVM_DEBUG(dbgs() << "\t\tThis is an AArch64 branch relocation.");
1048  SectionEntry &Section = Sections[SectionID];
1049 
1050  uint64_t Offset = RelI->getOffset();
1051  unsigned RelType = RelI->getType();
1052  // Look for an existing stub.
1053  StubMap::const_iterator i = Stubs.find(Value);
1054  if (i != Stubs.end()) {
1055  resolveRelocation(Section, Offset,
1056  (uint64_t)Section.getAddressWithOffset(i->second),
1057  RelType, 0);
1058  LLVM_DEBUG(dbgs() << " Stub function found\n");
1059  } else if (!resolveAArch64ShortBranch(SectionID, RelI, Value)) {
1060  // Create a new stub function.
1061  LLVM_DEBUG(dbgs() << " Create a new stub function\n");
1062  Stubs[Value] = Section.getStubOffset();
1063  uint8_t *StubTargetAddr = createStubFunction(
1064  Section.getAddressWithOffset(Section.getStubOffset()));
1065 
1066  RelocationEntry REmovz_g3(SectionID, StubTargetAddr - Section.getAddress(),
1067  ELF::R_AARCH64_MOVW_UABS_G3, Value.Addend);
1068  RelocationEntry REmovk_g2(SectionID,
1069  StubTargetAddr - Section.getAddress() + 4,
1070  ELF::R_AARCH64_MOVW_UABS_G2_NC, Value.Addend);
1071  RelocationEntry REmovk_g1(SectionID,
1072  StubTargetAddr - Section.getAddress() + 8,
1073  ELF::R_AARCH64_MOVW_UABS_G1_NC, Value.Addend);
1074  RelocationEntry REmovk_g0(SectionID,
1075  StubTargetAddr - Section.getAddress() + 12,
1076  ELF::R_AARCH64_MOVW_UABS_G0_NC, Value.Addend);
1077 
1078  if (Value.SymbolName) {
1079  addRelocationForSymbol(REmovz_g3, Value.SymbolName);
1080  addRelocationForSymbol(REmovk_g2, Value.SymbolName);
1081  addRelocationForSymbol(REmovk_g1, Value.SymbolName);
1082  addRelocationForSymbol(REmovk_g0, Value.SymbolName);
1083  } else {
1084  addRelocationForSection(REmovz_g3, Value.SectionID);
1085  addRelocationForSection(REmovk_g2, Value.SectionID);
1086  addRelocationForSection(REmovk_g1, Value.SectionID);
1087  addRelocationForSection(REmovk_g0, Value.SectionID);
1088  }
1089  resolveRelocation(Section, Offset,
1090  reinterpret_cast<uint64_t>(Section.getAddressWithOffset(
1091  Section.getStubOffset())),
1092  RelType, 0);
1093  Section.advanceStubOffset(getMaxStubSize());
1094  }
1095 }
1096 
1099  unsigned SectionID, relocation_iterator RelI, const ObjectFile &O,
1100  ObjSectionToIDMap &ObjSectionToID, StubMap &Stubs) {
1101  const auto &Obj = cast<ELFObjectFileBase>(O);
1102  uint64_t RelType = RelI->getType();
1103  int64_t Addend = 0;
1104  if (Expected<int64_t> AddendOrErr = ELFRelocationRef(*RelI).getAddend())
1105  Addend = *AddendOrErr;
1106  else
1107  consumeError(AddendOrErr.takeError());
1108  elf_symbol_iterator Symbol = RelI->getSymbol();
1109 
1110  // Obtain the symbol name which is referenced in the relocation
1111  StringRef TargetName;
1112  if (Symbol != Obj.symbol_end()) {
1113  if (auto TargetNameOrErr = Symbol->getName())
1114  TargetName = *TargetNameOrErr;
1115  else
1116  return TargetNameOrErr.takeError();
1117  }
1118  LLVM_DEBUG(dbgs() << "\t\tRelType: " << RelType << " Addend: " << Addend
1119  << " TargetName: " << TargetName << "\n");
1121  // First search for the symbol in the local symbol table
1122  SymbolRef::Type SymType = SymbolRef::ST_Unknown;
1123 
1124  // Search for the symbol in the global symbol table
1126  if (Symbol != Obj.symbol_end()) {
1127  gsi = GlobalSymbolTable.find(TargetName.data());
1128  Expected<SymbolRef::Type> SymTypeOrErr = Symbol->getType();
1129  if (!SymTypeOrErr) {
1130  std::string Buf;
1131  raw_string_ostream OS(Buf);
1132  logAllUnhandledErrors(SymTypeOrErr.takeError(), OS);
1133  OS.flush();
1134  report_fatal_error(Buf);
1135  }
1136  SymType = *SymTypeOrErr;
1137  }
1138  if (gsi != GlobalSymbolTable.end()) {
1139  const auto &SymInfo = gsi->second;
1140  Value.SectionID = SymInfo.getSectionID();
1141  Value.Offset = SymInfo.getOffset();
1142  Value.Addend = SymInfo.getOffset() + Addend;
1143  } else {
1144  switch (SymType) {
1145  case SymbolRef::ST_Debug: {
1146  // TODO: Now ELF SymbolRef::ST_Debug = STT_SECTION, it's not obviously
1147  // and can be changed by another developers. Maybe best way is add
1148  // a new symbol type ST_Section to SymbolRef and use it.
1149  auto SectionOrErr = Symbol->getSection();
1150  if (!SectionOrErr) {
1151  std::string Buf;
1152  raw_string_ostream OS(Buf);
1153  logAllUnhandledErrors(SectionOrErr.takeError(), OS);
1154  OS.flush();
1155  report_fatal_error(Buf);
1156  }
1157  section_iterator si = *SectionOrErr;
1158  if (si == Obj.section_end())
1159  llvm_unreachable("Symbol section not found, bad object file format!");
1160  LLVM_DEBUG(dbgs() << "\t\tThis is section symbol\n");
1161  bool isCode = si->isText();
1162  if (auto SectionIDOrErr = findOrEmitSection(Obj, (*si), isCode,
1163  ObjSectionToID))
1164  Value.SectionID = *SectionIDOrErr;
1165  else
1166  return SectionIDOrErr.takeError();
1167  Value.Addend = Addend;
1168  break;
1169  }
1170  case SymbolRef::ST_Data:
1171  case SymbolRef::ST_Function:
1172  case SymbolRef::ST_Unknown: {
1173  Value.SymbolName = TargetName.data();
1174  Value.Addend = Addend;
1175 
1176  // Absolute relocations will have a zero symbol ID (STN_UNDEF), which
1177  // will manifest here as a NULL symbol name.
1178  // We can set this as a valid (but empty) symbol name, and rely
1179  // on addRelocationForSymbol to handle this.
1180  if (!Value.SymbolName)
1181  Value.SymbolName = "";
1182  break;
1183  }
1184  default:
1185  llvm_unreachable("Unresolved symbol type!");
1186  break;
1187  }
1188  }
1189 
1190  uint64_t Offset = RelI->getOffset();
1191 
1192  LLVM_DEBUG(dbgs() << "\t\tSectionID: " << SectionID << " Offset: " << Offset
1193  << "\n");
1194  if ((Arch == Triple::aarch64 || Arch == Triple::aarch64_be)) {
1195  if (RelType == ELF::R_AARCH64_CALL26 || RelType == ELF::R_AARCH64_JUMP26) {
1196  resolveAArch64Branch(SectionID, Value, RelI, Stubs);
1197  } else if (RelType == ELF::R_AARCH64_ADR_GOT_PAGE) {
1198  // Craete new GOT entry or find existing one. If GOT entry is
1199  // to be created, then we also emit ABS64 relocation for it.
1200  uint64_t GOTOffset = findOrAllocGOTEntry(Value, ELF::R_AARCH64_ABS64);
1201  resolveGOTOffsetRelocation(SectionID, Offset, GOTOffset + Addend,
1202  ELF::R_AARCH64_ADR_PREL_PG_HI21);
1203 
1204  } else if (RelType == ELF::R_AARCH64_LD64_GOT_LO12_NC) {
1205  uint64_t GOTOffset = findOrAllocGOTEntry(Value, ELF::R_AARCH64_ABS64);
1206  resolveGOTOffsetRelocation(SectionID, Offset, GOTOffset + Addend,
1207  ELF::R_AARCH64_LDST64_ABS_LO12_NC);
1208  } else {
1209  processSimpleRelocation(SectionID, Offset, RelType, Value);
1210  }
1211  } else if (Arch == Triple::arm) {
1212  if (RelType == ELF::R_ARM_PC24 || RelType == ELF::R_ARM_CALL ||
1213  RelType == ELF::R_ARM_JUMP24) {
1214  // This is an ARM branch relocation, need to use a stub function.
1215  LLVM_DEBUG(dbgs() << "\t\tThis is an ARM branch relocation.\n");
1216  SectionEntry &Section = Sections[SectionID];
1217 
1218  // Look for an existing stub.
1219  StubMap::const_iterator i = Stubs.find(Value);
1220  if (i != Stubs.end()) {
1221  resolveRelocation(
1222  Section, Offset,
1223  reinterpret_cast<uint64_t>(Section.getAddressWithOffset(i->second)),
1224  RelType, 0);
1225  LLVM_DEBUG(dbgs() << " Stub function found\n");
1226  } else {
1227  // Create a new stub function.
1228  LLVM_DEBUG(dbgs() << " Create a new stub function\n");
1229  Stubs[Value] = Section.getStubOffset();
1230  uint8_t *StubTargetAddr = createStubFunction(
1231  Section.getAddressWithOffset(Section.getStubOffset()));
1232  RelocationEntry RE(SectionID, StubTargetAddr - Section.getAddress(),
1233  ELF::R_ARM_ABS32, Value.Addend);
1234  if (Value.SymbolName)
1236  else
1238 
1239  resolveRelocation(Section, Offset, reinterpret_cast<uint64_t>(
1240  Section.getAddressWithOffset(
1241  Section.getStubOffset())),
1242  RelType, 0);
1243  Section.advanceStubOffset(getMaxStubSize());
1244  }
1245  } else {
1246  uint32_t *Placeholder =
1247  reinterpret_cast<uint32_t*>(computePlaceholderAddress(SectionID, Offset));
1248  if (RelType == ELF::R_ARM_PREL31 || RelType == ELF::R_ARM_TARGET1 ||
1249  RelType == ELF::R_ARM_ABS32) {
1250  Value.Addend += *Placeholder;
1251  } else if (RelType == ELF::R_ARM_MOVW_ABS_NC || RelType == ELF::R_ARM_MOVT_ABS) {
1252  // See ELF for ARM documentation
1253  Value.Addend += (int16_t)((*Placeholder & 0xFFF) | (((*Placeholder >> 16) & 0xF) << 12));
1254  }
1255  processSimpleRelocation(SectionID, Offset, RelType, Value);
1256  }
1257  } else if (IsMipsO32ABI) {
1258  uint8_t *Placeholder = reinterpret_cast<uint8_t *>(
1259  computePlaceholderAddress(SectionID, Offset));
1260  uint32_t Opcode = readBytesUnaligned(Placeholder, 4);
1261  if (RelType == ELF::R_MIPS_26) {
1262  // This is an Mips branch relocation, need to use a stub function.
1263  LLVM_DEBUG(dbgs() << "\t\tThis is a Mips branch relocation.");
1264  SectionEntry &Section = Sections[SectionID];
1265 
1266  // Extract the addend from the instruction.
1267  // We shift up by two since the Value will be down shifted again
1268  // when applying the relocation.
1269  uint32_t Addend = (Opcode & 0x03ffffff) << 2;
1270 
1271  Value.Addend += Addend;
1272 
1273  // Look up for existing stub.
1274  StubMap::const_iterator i = Stubs.find(Value);
1275  if (i != Stubs.end()) {
1276  RelocationEntry RE(SectionID, Offset, RelType, i->second);
1277  addRelocationForSection(RE, SectionID);
1278  LLVM_DEBUG(dbgs() << " Stub function found\n");
1279  } else {
1280  // Create a new stub function.
1281  LLVM_DEBUG(dbgs() << " Create a new stub function\n");
1282  Stubs[Value] = Section.getStubOffset();
1283 
1284  unsigned AbiVariant = Obj.getPlatformFlags();
1285 
1286  uint8_t *StubTargetAddr = createStubFunction(
1287  Section.getAddressWithOffset(Section.getStubOffset()), AbiVariant);
1288 
1289  // Creating Hi and Lo relocations for the filled stub instructions.
1290  RelocationEntry REHi(SectionID, StubTargetAddr - Section.getAddress(),
1291  ELF::R_MIPS_HI16, Value.Addend);
1292  RelocationEntry RELo(SectionID,
1293  StubTargetAddr - Section.getAddress() + 4,
1294  ELF::R_MIPS_LO16, Value.Addend);
1295 
1296  if (Value.SymbolName) {
1297  addRelocationForSymbol(REHi, Value.SymbolName);
1298  addRelocationForSymbol(RELo, Value.SymbolName);
1299  } else {
1300  addRelocationForSection(REHi, Value.SectionID);
1301  addRelocationForSection(RELo, Value.SectionID);
1302  }
1303 
1304  RelocationEntry RE(SectionID, Offset, RelType, Section.getStubOffset());
1305  addRelocationForSection(RE, SectionID);
1306  Section.advanceStubOffset(getMaxStubSize());
1307  }
1308  } else if (RelType == ELF::R_MIPS_HI16 || RelType == ELF::R_MIPS_PCHI16) {
1309  int64_t Addend = (Opcode & 0x0000ffff) << 16;
1310  RelocationEntry RE(SectionID, Offset, RelType, Addend);
1311  PendingRelocs.push_back(std::make_pair(Value, RE));
1312  } else if (RelType == ELF::R_MIPS_LO16 || RelType == ELF::R_MIPS_PCLO16) {
1313  int64_t Addend = Value.Addend + SignExtend32<16>(Opcode & 0x0000ffff);
1314  for (auto I = PendingRelocs.begin(); I != PendingRelocs.end();) {
1315  const RelocationValueRef &MatchingValue = I->first;
1316  RelocationEntry &Reloc = I->second;
1317  if (MatchingValue == Value &&
1318  RelType == getMatchingLoRelocation(Reloc.RelType) &&
1319  SectionID == Reloc.SectionID) {
1320  Reloc.Addend += Addend;
1321  if (Value.SymbolName)
1322  addRelocationForSymbol(Reloc, Value.SymbolName);
1323  else
1324  addRelocationForSection(Reloc, Value.SectionID);
1325  I = PendingRelocs.erase(I);
1326  } else
1327  ++I;
1328  }
1329  RelocationEntry RE(SectionID, Offset, RelType, Addend);
1330  if (Value.SymbolName)
1332  else
1334  } else {
1335  if (RelType == ELF::R_MIPS_32)
1336  Value.Addend += Opcode;
1337  else if (RelType == ELF::R_MIPS_PC16)
1338  Value.Addend += SignExtend32<18>((Opcode & 0x0000ffff) << 2);
1339  else if (RelType == ELF::R_MIPS_PC19_S2)
1340  Value.Addend += SignExtend32<21>((Opcode & 0x0007ffff) << 2);
1341  else if (RelType == ELF::R_MIPS_PC21_S2)
1342  Value.Addend += SignExtend32<23>((Opcode & 0x001fffff) << 2);
1343  else if (RelType == ELF::R_MIPS_PC26_S2)
1344  Value.Addend += SignExtend32<28>((Opcode & 0x03ffffff) << 2);
1345  processSimpleRelocation(SectionID, Offset, RelType, Value);
1346  }
1347  } else if (IsMipsN32ABI || IsMipsN64ABI) {
1348  uint32_t r_type = RelType & 0xff;
1349  RelocationEntry RE(SectionID, Offset, RelType, Value.Addend);
1350  if (r_type == ELF::R_MIPS_CALL16 || r_type == ELF::R_MIPS_GOT_PAGE
1351  || r_type == ELF::R_MIPS_GOT_DISP) {
1352  StringMap<uint64_t>::iterator i = GOTSymbolOffsets.find(TargetName);
1353  if (i != GOTSymbolOffsets.end())
1354  RE.SymOffset = i->second;
1355  else {
1356  RE.SymOffset = allocateGOTEntries(1);
1357  GOTSymbolOffsets[TargetName] = RE.SymOffset;
1358  }
1359  if (Value.SymbolName)
1361  else
1363  } else if (RelType == ELF::R_MIPS_26) {
1364  // This is an Mips branch relocation, need to use a stub function.
1365  LLVM_DEBUG(dbgs() << "\t\tThis is a Mips branch relocation.");
1366  SectionEntry &Section = Sections[SectionID];
1367 
1368  // Look up for existing stub.
1369  StubMap::const_iterator i = Stubs.find(Value);
1370  if (i != Stubs.end()) {
1371  RelocationEntry RE(SectionID, Offset, RelType, i->second);
1372  addRelocationForSection(RE, SectionID);
1373  LLVM_DEBUG(dbgs() << " Stub function found\n");
1374  } else {
1375  // Create a new stub function.
1376  LLVM_DEBUG(dbgs() << " Create a new stub function\n");
1377  Stubs[Value] = Section.getStubOffset();
1378 
1379  unsigned AbiVariant = Obj.getPlatformFlags();
1380 
1381  uint8_t *StubTargetAddr = createStubFunction(
1382  Section.getAddressWithOffset(Section.getStubOffset()), AbiVariant);
1383 
1384  if (IsMipsN32ABI) {
1385  // Creating Hi and Lo relocations for the filled stub instructions.
1386  RelocationEntry REHi(SectionID, StubTargetAddr - Section.getAddress(),
1387  ELF::R_MIPS_HI16, Value.Addend);
1388  RelocationEntry RELo(SectionID,
1389  StubTargetAddr - Section.getAddress() + 4,
1390  ELF::R_MIPS_LO16, Value.Addend);
1391  if (Value.SymbolName) {
1392  addRelocationForSymbol(REHi, Value.SymbolName);
1393  addRelocationForSymbol(RELo, Value.SymbolName);
1394  } else {
1395  addRelocationForSection(REHi, Value.SectionID);
1396  addRelocationForSection(RELo, Value.SectionID);
1397  }
1398  } else {
1399  // Creating Highest, Higher, Hi and Lo relocations for the filled stub
1400  // instructions.
1401  RelocationEntry REHighest(SectionID,
1402  StubTargetAddr - Section.getAddress(),
1403  ELF::R_MIPS_HIGHEST, Value.Addend);
1404  RelocationEntry REHigher(SectionID,
1405  StubTargetAddr - Section.getAddress() + 4,
1406  ELF::R_MIPS_HIGHER, Value.Addend);
1407  RelocationEntry REHi(SectionID,
1408  StubTargetAddr - Section.getAddress() + 12,
1409  ELF::R_MIPS_HI16, Value.Addend);
1410  RelocationEntry RELo(SectionID,
1411  StubTargetAddr - Section.getAddress() + 20,
1412  ELF::R_MIPS_LO16, Value.Addend);
1413  if (Value.SymbolName) {
1414  addRelocationForSymbol(REHighest, Value.SymbolName);
1415  addRelocationForSymbol(REHigher, Value.SymbolName);
1416  addRelocationForSymbol(REHi, Value.SymbolName);
1417  addRelocationForSymbol(RELo, Value.SymbolName);
1418  } else {
1419  addRelocationForSection(REHighest, Value.SectionID);
1420  addRelocationForSection(REHigher, Value.SectionID);
1421  addRelocationForSection(REHi, Value.SectionID);
1422  addRelocationForSection(RELo, Value.SectionID);
1423  }
1424  }
1425  RelocationEntry RE(SectionID, Offset, RelType, Section.getStubOffset());
1426  addRelocationForSection(RE, SectionID);
1427  Section.advanceStubOffset(getMaxStubSize());
1428  }
1429  } else {
1430  processSimpleRelocation(SectionID, Offset, RelType, Value);
1431  }
1432 
1433  } else if (Arch == Triple::ppc64 || Arch == Triple::ppc64le) {
1434  if (RelType == ELF::R_PPC64_REL24) {
1435  // Determine ABI variant in use for this object.
1436  unsigned AbiVariant = Obj.getPlatformFlags();
1437  AbiVariant &= ELF::EF_PPC64_ABI;
1438  // A PPC branch relocation will need a stub function if the target is
1439  // an external symbol (either Value.SymbolName is set, or SymType is
1440  // Symbol::ST_Unknown) or if the target address is not within the
1441  // signed 24-bits branch address.
1442  SectionEntry &Section = Sections[SectionID];
1443  uint8_t *Target = Section.getAddressWithOffset(Offset);
1444  bool RangeOverflow = false;
1445  bool IsExtern = Value.SymbolName || SymType == SymbolRef::ST_Unknown;
1446  if (!IsExtern) {
1447  if (AbiVariant != 2) {
1448  // In the ELFv1 ABI, a function call may point to the .opd entry,
1449  // so the final symbol value is calculated based on the relocation
1450  // values in the .opd section.
1451  if (auto Err = findOPDEntrySection(Obj, ObjSectionToID, Value))
1452  return std::move(Err);
1453  } else {
1454  // In the ELFv2 ABI, a function symbol may provide a local entry
1455  // point, which must be used for direct calls.
1456  if (Value.SectionID == SectionID){
1457  uint8_t SymOther = Symbol->getOther();
1458  Value.Addend += ELF::decodePPC64LocalEntryOffset(SymOther);
1459  }
1460  }
1461  uint8_t *RelocTarget =
1462  Sections[Value.SectionID].getAddressWithOffset(Value.Addend);
1463  int64_t delta = static_cast<int64_t>(Target - RelocTarget);
1464  // If it is within 26-bits branch range, just set the branch target
1465  if (SignExtend64<26>(delta) != delta) {
1466  RangeOverflow = true;
1467  } else if ((AbiVariant != 2) ||
1468  (AbiVariant == 2 && Value.SectionID == SectionID)) {
1469  RelocationEntry RE(SectionID, Offset, RelType, Value.Addend);
1471  }
1472  }
1473  if (IsExtern || (AbiVariant == 2 && Value.SectionID != SectionID) ||
1474  RangeOverflow) {
1475  // It is an external symbol (either Value.SymbolName is set, or
1476  // SymType is SymbolRef::ST_Unknown) or out of range.
1477  StubMap::const_iterator i = Stubs.find(Value);
1478  if (i != Stubs.end()) {
1479  // Symbol function stub already created, just relocate to it
1480  resolveRelocation(Section, Offset,
1481  reinterpret_cast<uint64_t>(
1482  Section.getAddressWithOffset(i->second)),
1483  RelType, 0);
1484  LLVM_DEBUG(dbgs() << " Stub function found\n");
1485  } else {
1486  // Create a new stub function.
1487  LLVM_DEBUG(dbgs() << " Create a new stub function\n");
1488  Stubs[Value] = Section.getStubOffset();
1489  uint8_t *StubTargetAddr = createStubFunction(
1490  Section.getAddressWithOffset(Section.getStubOffset()),
1491  AbiVariant);
1492  RelocationEntry RE(SectionID, StubTargetAddr - Section.getAddress(),
1493  ELF::R_PPC64_ADDR64, Value.Addend);
1494 
1495  // Generates the 64-bits address loads as exemplified in section
1496  // 4.5.1 in PPC64 ELF ABI. Note that the relocations need to
1497  // apply to the low part of the instructions, so we have to update
1498  // the offset according to the target endianness.
1499  uint64_t StubRelocOffset = StubTargetAddr - Section.getAddress();
1500  if (!IsTargetLittleEndian)
1501  StubRelocOffset += 2;
1502 
1503  RelocationEntry REhst(SectionID, StubRelocOffset + 0,
1504  ELF::R_PPC64_ADDR16_HIGHEST, Value.Addend);
1505  RelocationEntry REhr(SectionID, StubRelocOffset + 4,
1506  ELF::R_PPC64_ADDR16_HIGHER, Value.Addend);
1507  RelocationEntry REh(SectionID, StubRelocOffset + 12,
1508  ELF::R_PPC64_ADDR16_HI, Value.Addend);
1509  RelocationEntry REl(SectionID, StubRelocOffset + 16,
1510  ELF::R_PPC64_ADDR16_LO, Value.Addend);
1511 
1512  if (Value.SymbolName) {
1513  addRelocationForSymbol(REhst, Value.SymbolName);
1514  addRelocationForSymbol(REhr, Value.SymbolName);
1515  addRelocationForSymbol(REh, Value.SymbolName);
1516  addRelocationForSymbol(REl, Value.SymbolName);
1517  } else {
1518  addRelocationForSection(REhst, Value.SectionID);
1519  addRelocationForSection(REhr, Value.SectionID);
1520  addRelocationForSection(REh, Value.SectionID);
1521  addRelocationForSection(REl, Value.SectionID);
1522  }
1523 
1524  resolveRelocation(Section, Offset, reinterpret_cast<uint64_t>(
1525  Section.getAddressWithOffset(
1526  Section.getStubOffset())),
1527  RelType, 0);
1528  Section.advanceStubOffset(getMaxStubSize());
1529  }
1530  if (IsExtern || (AbiVariant == 2 && Value.SectionID != SectionID)) {
1531  // Restore the TOC for external calls
1532  if (AbiVariant == 2)
1533  writeInt32BE(Target + 4, 0xE8410018); // ld r2,24(r1)
1534  else
1535  writeInt32BE(Target + 4, 0xE8410028); // ld r2,40(r1)
1536  }
1537  }
1538  } else if (RelType == ELF::R_PPC64_TOC16 ||
1539  RelType == ELF::R_PPC64_TOC16_DS ||
1540  RelType == ELF::R_PPC64_TOC16_LO ||
1541  RelType == ELF::R_PPC64_TOC16_LO_DS ||
1542  RelType == ELF::R_PPC64_TOC16_HI ||
1543  RelType == ELF::R_PPC64_TOC16_HA) {
1544  // These relocations are supposed to subtract the TOC address from
1545  // the final value. This does not fit cleanly into the RuntimeDyld
1546  // scheme, since there may be *two* sections involved in determining
1547  // the relocation value (the section of the symbol referred to by the
1548  // relocation, and the TOC section associated with the current module).
1549  //
1550  // Fortunately, these relocations are currently only ever generated
1551  // referring to symbols that themselves reside in the TOC, which means
1552  // that the two sections are actually the same. Thus they cancel out
1553  // and we can immediately resolve the relocation right now.
1554  switch (RelType) {
1555  case ELF::R_PPC64_TOC16: RelType = ELF::R_PPC64_ADDR16; break;
1556  case ELF::R_PPC64_TOC16_DS: RelType = ELF::R_PPC64_ADDR16_DS; break;
1557  case ELF::R_PPC64_TOC16_LO: RelType = ELF::R_PPC64_ADDR16_LO; break;
1558  case ELF::R_PPC64_TOC16_LO_DS: RelType = ELF::R_PPC64_ADDR16_LO_DS; break;
1559  case ELF::R_PPC64_TOC16_HI: RelType = ELF::R_PPC64_ADDR16_HI; break;
1560  case ELF::R_PPC64_TOC16_HA: RelType = ELF::R_PPC64_ADDR16_HA; break;
1561  default: llvm_unreachable("Wrong relocation type.");
1562  }
1563 
1564  RelocationValueRef TOCValue;
1565  if (auto Err = findPPC64TOCSection(Obj, ObjSectionToID, TOCValue))
1566  return std::move(Err);
1567  if (Value.SymbolName || Value.SectionID != TOCValue.SectionID)
1568  llvm_unreachable("Unsupported TOC relocation.");
1569  Value.Addend -= TOCValue.Addend;
1570  resolveRelocation(Sections[SectionID], Offset, Value.Addend, RelType, 0);
1571  } else {
1572  // There are two ways to refer to the TOC address directly: either
1573  // via a ELF::R_PPC64_TOC relocation (where both symbol and addend are
1574  // ignored), or via any relocation that refers to the magic ".TOC."
1575  // symbols (in which case the addend is respected).
1576  if (RelType == ELF::R_PPC64_TOC) {
1577  RelType = ELF::R_PPC64_ADDR64;
1578  if (auto Err = findPPC64TOCSection(Obj, ObjSectionToID, Value))
1579  return std::move(Err);
1580  } else if (TargetName == ".TOC.") {
1581  if (auto Err = findPPC64TOCSection(Obj, ObjSectionToID, Value))
1582  return std::move(Err);
1583  Value.Addend += Addend;
1584  }
1585 
1586  RelocationEntry RE(SectionID, Offset, RelType, Value.Addend);
1587 
1588  if (Value.SymbolName)
1590  else
1592  }
1593  } else if (Arch == Triple::systemz &&
1594  (RelType == ELF::R_390_PLT32DBL || RelType == ELF::R_390_GOTENT)) {
1595  // Create function stubs for both PLT and GOT references, regardless of
1596  // whether the GOT reference is to data or code. The stub contains the
1597  // full address of the symbol, as needed by GOT references, and the
1598  // executable part only adds an overhead of 8 bytes.
1599  //
1600  // We could try to conserve space by allocating the code and data
1601  // parts of the stub separately. However, as things stand, we allocate
1602  // a stub for every relocation, so using a GOT in JIT code should be
1603  // no less space efficient than using an explicit constant pool.
1604  LLVM_DEBUG(dbgs() << "\t\tThis is a SystemZ indirect relocation.");
1605  SectionEntry &Section = Sections[SectionID];
1606 
1607  // Look for an existing stub.
1608  StubMap::const_iterator i = Stubs.find(Value);
1609  uintptr_t StubAddress;
1610  if (i != Stubs.end()) {
1611  StubAddress = uintptr_t(Section.getAddressWithOffset(i->second));
1612  LLVM_DEBUG(dbgs() << " Stub function found\n");
1613  } else {
1614  // Create a new stub function.
1615  LLVM_DEBUG(dbgs() << " Create a new stub function\n");
1616 
1617  uintptr_t BaseAddress = uintptr_t(Section.getAddress());
1618  uintptr_t StubAlignment = getStubAlignment();
1619  StubAddress =
1620  (BaseAddress + Section.getStubOffset() + StubAlignment - 1) &
1621  -StubAlignment;
1622  unsigned StubOffset = StubAddress - BaseAddress;
1623 
1624  Stubs[Value] = StubOffset;
1625  createStubFunction((uint8_t *)StubAddress);
1626  RelocationEntry RE(SectionID, StubOffset + 8, ELF::R_390_64,
1627  Value.Offset);
1628  if (Value.SymbolName)
1630  else
1632  Section.advanceStubOffset(getMaxStubSize());
1633  }
1634 
1635  if (RelType == ELF::R_390_GOTENT)
1636  resolveRelocation(Section, Offset, StubAddress + 8, ELF::R_390_PC32DBL,
1637  Addend);
1638  else
1639  resolveRelocation(Section, Offset, StubAddress, RelType, Addend);
1640  } else if (Arch == Triple::x86_64) {
1641  if (RelType == ELF::R_X86_64_PLT32) {
1642  // The way the PLT relocations normally work is that the linker allocates
1643  // the
1644  // PLT and this relocation makes a PC-relative call into the PLT. The PLT
1645  // entry will then jump to an address provided by the GOT. On first call,
1646  // the
1647  // GOT address will point back into PLT code that resolves the symbol. After
1648  // the first call, the GOT entry points to the actual function.
1649  //
1650  // For local functions we're ignoring all of that here and just replacing
1651  // the PLT32 relocation type with PC32, which will translate the relocation
1652  // into a PC-relative call directly to the function. For external symbols we
1653  // can't be sure the function will be within 2^32 bytes of the call site, so
1654  // we need to create a stub, which calls into the GOT. This case is
1655  // equivalent to the usual PLT implementation except that we use the stub
1656  // mechanism in RuntimeDyld (which puts stubs at the end of the section)
1657  // rather than allocating a PLT section.
1658  if (Value.SymbolName) {
1659  // This is a call to an external function.
1660  // Look for an existing stub.
1661  SectionEntry &Section = Sections[SectionID];
1662  StubMap::const_iterator i = Stubs.find(Value);
1663  uintptr_t StubAddress;
1664  if (i != Stubs.end()) {
1665  StubAddress = uintptr_t(Section.getAddress()) + i->second;
1666  LLVM_DEBUG(dbgs() << " Stub function found\n");
1667  } else {
1668  // Create a new stub function (equivalent to a PLT entry).
1669  LLVM_DEBUG(dbgs() << " Create a new stub function\n");
1670 
1671  uintptr_t BaseAddress = uintptr_t(Section.getAddress());
1672  uintptr_t StubAlignment = getStubAlignment();
1673  StubAddress =
1674  (BaseAddress + Section.getStubOffset() + StubAlignment - 1) &
1675  -StubAlignment;
1676  unsigned StubOffset = StubAddress - BaseAddress;
1677  Stubs[Value] = StubOffset;
1678  createStubFunction((uint8_t *)StubAddress);
1679 
1680  // Bump our stub offset counter
1681  Section.advanceStubOffset(getMaxStubSize());
1682 
1683  // Allocate a GOT Entry
1684  uint64_t GOTOffset = allocateGOTEntries(1);
1685 
1686  // The load of the GOT address has an addend of -4
1687  resolveGOTOffsetRelocation(SectionID, StubOffset + 2, GOTOffset - 4,
1688  ELF::R_X86_64_PC32);
1689 
1690  // Fill in the value of the symbol we're targeting into the GOT
1692  computeGOTOffsetRE(GOTOffset, 0, ELF::R_X86_64_64),
1693  Value.SymbolName);
1694  }
1695 
1696  // Make the target call a call into the stub table.
1697  resolveRelocation(Section, Offset, StubAddress, ELF::R_X86_64_PC32,
1698  Addend);
1699  } else {
1700  RelocationEntry RE(SectionID, Offset, ELF::R_X86_64_PC32, Value.Addend,
1701  Value.Offset);
1703  }
1704  } else if (RelType == ELF::R_X86_64_GOTPCREL ||
1705  RelType == ELF::R_X86_64_GOTPCRELX ||
1706  RelType == ELF::R_X86_64_REX_GOTPCRELX) {
1707  uint64_t GOTOffset = allocateGOTEntries(1);
1708  resolveGOTOffsetRelocation(SectionID, Offset, GOTOffset + Addend,
1709  ELF::R_X86_64_PC32);
1710 
1711  // Fill in the value of the symbol we're targeting into the GOT
1712  RelocationEntry RE =
1713  computeGOTOffsetRE(GOTOffset, Value.Offset, ELF::R_X86_64_64);
1714  if (Value.SymbolName)
1716  else
1718  } else if (RelType == ELF::R_X86_64_GOT64) {
1719  // Fill in a 64-bit GOT offset.
1720  uint64_t GOTOffset = allocateGOTEntries(1);
1721  resolveRelocation(Sections[SectionID], Offset, GOTOffset,
1722  ELF::R_X86_64_64, 0);
1723 
1724  // Fill in the value of the symbol we're targeting into the GOT
1725  RelocationEntry RE =
1726  computeGOTOffsetRE(GOTOffset, Value.Offset, ELF::R_X86_64_64);
1727  if (Value.SymbolName)
1729  else
1731  } else if (RelType == ELF::R_X86_64_GOTPC64) {
1732  // Materialize the address of the base of the GOT relative to the PC.
1733  // This doesn't create a GOT entry, but it does mean we need a GOT
1734  // section.
1735  (void)allocateGOTEntries(0);
1736  resolveGOTOffsetRelocation(SectionID, Offset, Addend, ELF::R_X86_64_PC64);
1737  } else if (RelType == ELF::R_X86_64_GOTOFF64) {
1738  // GOTOFF relocations ultimately require a section difference relocation.
1739  (void)allocateGOTEntries(0);
1740  processSimpleRelocation(SectionID, Offset, RelType, Value);
1741  } else if (RelType == ELF::R_X86_64_PC32) {
1742  Value.Addend += support::ulittle32_t::ref(computePlaceholderAddress(SectionID, Offset));
1743  processSimpleRelocation(SectionID, Offset, RelType, Value);
1744  } else if (RelType == ELF::R_X86_64_PC64) {
1745  Value.Addend += support::ulittle64_t::ref(computePlaceholderAddress(SectionID, Offset));
1746  processSimpleRelocation(SectionID, Offset, RelType, Value);
1747  } else {
1748  processSimpleRelocation(SectionID, Offset, RelType, Value);
1749  }
1750  } else {
1751  if (Arch == Triple::x86) {
1752  Value.Addend += support::ulittle32_t::ref(computePlaceholderAddress(SectionID, Offset));
1753  }
1754  processSimpleRelocation(SectionID, Offset, RelType, Value);
1755  }
1756  return ++RelI;
1757 }
1758 
1760  // We don't use the GOT in all of these cases, but it's essentially free
1761  // to put them all here.
1762  size_t Result = 0;
1763  switch (Arch) {
1764  case Triple::x86_64:
1765  case Triple::aarch64:
1766  case Triple::aarch64_be:
1767  case Triple::ppc64:
1768  case Triple::ppc64le:
1769  case Triple::systemz:
1770  Result = sizeof(uint64_t);
1771  break;
1772  case Triple::x86:
1773  case Triple::arm:
1774  case Triple::thumb:
1775  Result = sizeof(uint32_t);
1776  break;
1777  case Triple::mips:
1778  case Triple::mipsel:
1779  case Triple::mips64:
1780  case Triple::mips64el:
1781  if (IsMipsO32ABI || IsMipsN32ABI)
1782  Result = sizeof(uint32_t);
1783  else if (IsMipsN64ABI)
1784  Result = sizeof(uint64_t);
1785  else
1786  llvm_unreachable("Mips ABI not handled");
1787  break;
1788  default:
1789  llvm_unreachable("Unsupported CPU type!");
1790  }
1791  return Result;
1792 }
1793 
1794 uint64_t RuntimeDyldELF::allocateGOTEntries(unsigned no) {
1795  if (GOTSectionID == 0) {
1796  GOTSectionID = Sections.size();
1797  // Reserve a section id. We'll allocate the section later
1798  // once we know the total size
1799  Sections.push_back(SectionEntry(".got", nullptr, 0, 0, 0));
1800  }
1801  uint64_t StartOffset = CurrentGOTIndex * getGOTEntrySize();
1802  CurrentGOTIndex += no;
1803  return StartOffset;
1804 }
1805 
1806 uint64_t RuntimeDyldELF::findOrAllocGOTEntry(const RelocationValueRef &Value,
1807  unsigned GOTRelType) {
1808  auto E = GOTOffsetMap.insert({Value, 0});
1809  if (E.second) {
1810  uint64_t GOTOffset = allocateGOTEntries(1);
1811 
1812  // Create relocation for newly created GOT entry
1813  RelocationEntry RE =
1814  computeGOTOffsetRE(GOTOffset, Value.Offset, GOTRelType);
1815  if (Value.SymbolName)
1817  else
1819 
1820  E.first->second = GOTOffset;
1821  }
1822 
1823  return E.first->second;
1824 }
1825 
1826 void RuntimeDyldELF::resolveGOTOffsetRelocation(unsigned SectionID,
1827  uint64_t Offset,
1828  uint64_t GOTOffset,
1829  uint32_t Type) {
1830  // Fill in the relative address of the GOT Entry into the stub
1831  RelocationEntry GOTRE(SectionID, Offset, Type, GOTOffset);
1832  addRelocationForSection(GOTRE, GOTSectionID);
1833 }
1834 
1835 RelocationEntry RuntimeDyldELF::computeGOTOffsetRE(uint64_t GOTOffset,
1836  uint64_t SymbolOffset,
1837  uint32_t Type) {
1838  return RelocationEntry(GOTSectionID, GOTOffset, Type, SymbolOffset);
1839 }
1840 
1842  ObjSectionToIDMap &SectionMap) {
1843  if (IsMipsO32ABI)
1844  if (!PendingRelocs.empty())
1845  return make_error<RuntimeDyldError>("Can't find matching LO16 reloc");
1846 
1847  // If necessary, allocate the global offset table
1848  if (GOTSectionID != 0) {
1849  // Allocate memory for the section
1850  size_t TotalSize = CurrentGOTIndex * getGOTEntrySize();
1851  uint8_t *Addr = MemMgr.allocateDataSection(TotalSize, getGOTEntrySize(),
1852  GOTSectionID, ".got", false);
1853  if (!Addr)
1854  return make_error<RuntimeDyldError>("Unable to allocate memory for GOT!");
1855 
1856  Sections[GOTSectionID] =
1857  SectionEntry(".got", Addr, TotalSize, TotalSize, 0);
1858 
1859  // For now, initialize all GOT entries to zero. We'll fill them in as
1860  // needed when GOT-based relocations are applied.
1861  memset(Addr, 0, TotalSize);
1862  if (IsMipsN32ABI || IsMipsN64ABI) {
1863  // To correctly resolve Mips GOT relocations, we need a mapping from
1864  // object's sections to GOTs.
1865  for (section_iterator SI = Obj.section_begin(), SE = Obj.section_end();
1866  SI != SE; ++SI) {
1867  if (SI->relocation_begin() != SI->relocation_end()) {
1868  section_iterator RelocatedSection = SI->getRelocatedSection();
1869  ObjSectionToIDMap::iterator i = SectionMap.find(*RelocatedSection);
1870  assert (i != SectionMap.end());
1871  SectionToGOTMap[i->second] = GOTSectionID;
1872  }
1873  }
1874  GOTSymbolOffsets.clear();
1875  }
1876  }
1877 
1878  // Look for and record the EH frame section.
1879  ObjSectionToIDMap::iterator i, e;
1880  for (i = SectionMap.begin(), e = SectionMap.end(); i != e; ++i) {
1881  const SectionRef &Section = i->first;
1882  StringRef Name;
1883  Section.getName(Name);
1884  if (Name == ".eh_frame") {
1885  UnregisteredEHFrameSections.push_back(i->second);
1886  break;
1887  }
1888  }
1889 
1890  GOTSectionID = 0;
1891  CurrentGOTIndex = 0;
1892 
1893  return Error::success();
1894 }
1895 
1897  return Obj.isELF();
1898 }
1899 
1900 bool RuntimeDyldELF::relocationNeedsGot(const RelocationRef &R) const {
1901  unsigned RelTy = R.getType();
1903  return RelTy == ELF::R_AARCH64_ADR_GOT_PAGE ||
1904  RelTy == ELF::R_AARCH64_LD64_GOT_LO12_NC;
1905 
1906  if (Arch == Triple::x86_64)
1907  return RelTy == ELF::R_X86_64_GOTPCREL ||
1908  RelTy == ELF::R_X86_64_GOTPCRELX ||
1909  RelTy == ELF::R_X86_64_GOT64 ||
1910  RelTy == ELF::R_X86_64_REX_GOTPCRELX;
1911  return false;
1912 }
1913 
1914 bool RuntimeDyldELF::relocationNeedsStub(const RelocationRef &R) const {
1915  if (Arch != Triple::x86_64)
1916  return true; // Conservative answer
1917 
1918  switch (R.getType()) {
1919  default:
1920  return true; // Conservative answer
1921 
1922 
1923  case ELF::R_X86_64_GOTPCREL:
1924  case ELF::R_X86_64_GOTPCRELX:
1925  case ELF::R_X86_64_REX_GOTPCRELX:
1926  case ELF::R_X86_64_GOTPC64:
1927  case ELF::R_X86_64_GOT64:
1928  case ELF::R_X86_64_GOTOFF64:
1929  case ELF::R_X86_64_PC32:
1930  case ELF::R_X86_64_PC64:
1931  case ELF::R_X86_64_64:
1932  // We know that these reloation types won't need a stub function. This list
1933  // can be extended as needed.
1934  return false;
1935  }
1936 }
1937 
1938 } // namespace llvm
RelocationEntry - used to represent relocations internally in the dynamic linker. ...
static void or32AArch64Imm(void *L, uint64_t Imm)
LLVM_ATTRIBUTE_NORETURN void report_fatal_error(Error Err, bool gen_crash_diag=true)
Report a serious error, calling any installed error handler.
Definition: Error.cpp:139
This class represents lattice values for constants.
Definition: AllocatorList.h:23
void writeInt16BE(uint8_t *Addr, uint16_t Value)
amdgpu Simplify well known AMD library false FunctionCallee Value const Twine & Name
StringRef getFileName() const
Definition: Binary.cpp:41
void push_back(const T &Elt)
Definition: SmallVector.h:211
uint64_t readBytesUnaligned(uint8_t *Src, unsigned Size) const
Endian-aware read Read the least significant Size bytes from Src.
uint64_t getLoadAddressWithOffset(unsigned OffsetBytes) const
Return the load address of this section with an offset.
RuntimeDyld::MemoryManager & MemMgr
format_object< Ts... > format(const char *Fmt, const Ts &... Vals)
These are helper functions used to produce formatted output.
Definition: Format.h:123
size_t getGOTEntrySize() override
iterator find(StringRef Key)
Definition: StringMap.h:332
constexpr bool isInt< 8 >(int64_t x)
Definition: MathExtras.h:302
This class is the base class for all object file types.
Definition: ObjectFile.h:226
static uint16_t applyPPChigher(uint64_t value)
void write32le(void *P, uint32_t V)
Definition: Endian.h:418
static uint16_t applyPPChighesta(uint64_t value)
uint8_t * getAddress() const
Error takeError()
Take ownership of the stored error.
Definition: Error.h:552
static uint16_t applyPPChighera(uint64_t value)
static std::unique_ptr< RuntimeDyldELF > create(Triple::ArchType Arch, RuntimeDyld::MemoryManager &MemMgr, JITSymbolResolver &Resolver)
static int64_t decodePPC64LocalEntryOffset(unsigned Other)
Definition: ELF.h:392
unsigned SectionID
SectionID - the section this relocation points to.
amdgpu aa AMDGPU Address space based Alias Analysis Wrapper
DataRefImpl getRawDataRefImpl() const
Definition: SymbolicFile.h:203
This is a value type class that represents a single relocation in the list of relocations in the obje...
Definition: ObjectFile.h:52
std::unique_ptr< RuntimeDyld::LoadedObjectInfo > loadObject(const object::ObjectFile &O) override
std::map< RelocationValueRef, uintptr_t > StubMap
Tagged union holding either a T or a Error.
Definition: CachePruning.h:22
section_iterator_range sections() const
Definition: ObjectFile.h:315
Expected< relocation_iterator > processRelocationRef(unsigned SectionID, relocation_iterator RelI, const ObjectFile &Obj, ObjSectionToIDMap &ObjSectionToID, StubMap &Stubs) override
Parses one or more object file relocations (some object files use relocation pairs) and stores it to ...
static uint16_t applyPPChi(uint64_t value)
std::enable_if<!is_simple_type< Y >::value, typename cast_retty< X, const Y >::ret_type >::type cast(const Y &Val)
Definition: Casting.h:249
Expected< section_iterator > getSection() const
Get section this symbol is defined in reference to.
Definition: ObjectFile.h:400
const Elf_Sym * getSymbol(DataRefImpl Sym) const
#define P(N)
void addRelocationForSymbol(const RelocationEntry &RE, StringRef SymbolName)
virtual uint8_t getBytesInAddress() const =0
The number of bytes used to represent an address in this object file format.
The instances of the Type class are immutable: once they are created, they are never changed...
Definition: Type.h:45
void registerEHFrames() override
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
Error errorCodeToError(std::error_code EC)
Helper for converting an std::error_code to a Error.
Definition: Error.cpp:87
static uint64_t getBits(uint64_t Val, int Start, int End)
void addRelocationForSection(const RelocationEntry &RE, unsigned SectionID)
Interface for looking up the initializer for a variable name, used by Init::resolveReferences.
Definition: Record.h:1856
static StringRef getArchTypePrefix(ArchType Kind)
getArchTypePrefix - Get the "prefix" canonical name for the Kind architecture.
Definition: Triple.cpp:78
Expected< int64_t > getAddend() const
Symbol resolution interface.
Definition: JITSymbol.h:324
static uint16_t applyPPClo(uint64_t value)
virtual basic_symbol_iterator symbol_end() const =0
static Expected< ELFObjectFile< ELFT > > create(MemoryBufferRef Object)
void writeInt32BE(uint8_t *Addr, uint32_t Value)
Expected< unsigned > findOrEmitSection(const ObjectFile &Obj, const SectionRef &Section, bool IsCode, ObjSectionToIDMap &LocalSections)
Find Section in LocalSections.
bool isCompatibleFile(const object::ObjectFile &Obj) const override
DenseMap< SID, SID > SectionToGOTMap
static void write(bool isBE, void *P, T V)
virtual uint8_t * allocateDataSection(uintptr_t Size, unsigned Alignment, unsigned SectionID, StringRef SectionName, bool IsReadOnly)=0
Allocate a memory block of (at least) the given size suitable for data.
bool isELF() const
Definition: Binary.h:112
DataRefImpl getRawDataRefImpl() const
Definition: ObjectFile.h:517
void consumeError(Error Err)
Consume a Error without doing anything.
Definition: Error.h:981
size_t size() const
Definition: SmallVector.h:52
void logAllUnhandledErrors(Error E, raw_ostream &OS, Twine ErrorBanner={})
Log all errors (if any) in E to OS.
Definition: Error.cpp:61
uint64_t getType() const
Definition: ObjectFile.h:547
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
bool isLittleEndian() const
Definition: Binary.h:138
static uint16_t applyPPChighest(uint64_t value)
void handleAllErrors(Error E, HandlerTs &&... Handlers)
Behaves the same as handleErrors, except that by contract all errors must be handled by the given han...
Definition: Error.h:904
static ErrorSuccess success()
Create a success value.
Definition: Error.h:326
constexpr bool isInt< 32 >(int64_t x)
Definition: MathExtras.h:308
Error finalizeLoad(const ObjectFile &Obj, ObjSectionToIDMap &SectionMap) override
virtual section_iterator section_begin() const =0
Expected< SymbolRef::Type > getType() const
Definition: ObjectFile.h:404
int64_t Addend
Addend - the relocation addend encoded in the instruction itself.
std::error_code getName(StringRef &Result) const
Definition: ObjectFile.h:437
uint32_t RelType
RelType - relocation type.
JITSymbolResolver & Resolver
virtual unsigned getPlatformFlags() const =0
Returns platform-specific object flags, if any.
LLVM_NODISCARD bool isa(const Y &Val)
Definition: Casting.h:141
static void or32le(void *P, int32_t V)
uint8_t * createStubFunction(uint8_t *Addr, unsigned AbiVariant=0)
Emits long jump instruction to Addr.
raw_ostream & dbgs()
dbgs() - This returns a reference to a raw_ostream for debugging messages.
Definition: Debug.cpp:132
StringMap - This is an unconventional map that is specialized for handling keys that are "strings"...
Definition: StringMap.h:219
Target - Wrapper for Target specific information.
static std::unique_ptr< MemoryBuffer > getMemBufferCopy(StringRef InputData, const Twine &BufferName="")
Open the specified memory range as a MemoryBuffer, copying the contents and taking ownership of it...
uintptr_t getStubOffset() const
This is a value type class that represents a single symbol in the list of symbols in the object file...
Definition: ObjectFile.h:165
Triple::ArchType Arch
LLVM_NODISCARD bool equals(StringRef RHS) const
equals - Check for string equality, this is more efficient than compare() when the relative ordering ...
Definition: StringRef.h:160
uint64_t Offset
Offset - offset into the section.
virtual section_iterator section_end() const =0
std::map< SectionRef, unsigned > ObjSectionToIDMap
uint8_t * getAddressWithOffset(unsigned OffsetBytes) const
Return the address of this section with an offset.
#define I(x, y, z)
Definition: MD5.cpp:58
void writeInt64BE(uint8_t *Addr, uint64_t Value)
uint32_t read32le(const void *P)
Definition: Endian.h:383
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.
LLVM_NODISCARD const char * data() const
data - Get a pointer to the start of the string (which may not be null terminated).
Definition: StringRef.h:122
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
RuntimeDyldELF(RuntimeDyld::MemoryManager &MemMgr, JITSymbolResolver &Resolver)
A raw_ostream that writes to an std::string.
Definition: raw_ostream.h:482
LLVM Value Representation.
Definition: Value.h:72
RTDyldSymbolTable GlobalSymbolTable
Lightweight error class with error context and mandatory checking.
Definition: Error.h:157
std::underlying_type< E >::type Mask()
Get a bitmask with 1s in all places up to the high-order bit of E&#39;s largest value.
Definition: BitmaskEnum.h:80
static void write32AArch64Addr(void *L, uint64_t Imm)
const char SectionName[]
Definition: AMDGPUPTNote.h:23
void advanceStubOffset(unsigned StubSize)
#define LLVM_ELF_IMPORT_TYPES_ELFT(ELFT)
Definition: ELFTypes.h:103
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:48
virtual void registerEHFrames(uint8_t *Addr, uint64_t LoadAddr, size_t Size)=0
Register the EH frames with the runtime so that c++ exceptions work.
Expected< ObjSectionToIDMap > loadObjectImpl(const object::ObjectFile &Obj)
static uint16_t applyPPCha(uint64_t value)
#define LLVM_DEBUG(X)
Definition: Debug.h:122
virtual StringRef getFileFormatName() const =0
StringRef getData() const
Definition: Binary.cpp:39
iterator end()
Definition: StringMap.h:317
This is a value type class that represents a single section in the list of sections in the object fil...
Definition: ObjectFile.h:81