1 //===-- RuntimeDyldELF.cpp - Run-time dynamic linker for MC-JIT -*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // Implementation of ELF support for the MC-JIT runtime dynamic linker.
12 //===----------------------------------------------------------------------===//
14 #include "RuntimeDyldELF.h"
15 #include "RuntimeDyldCheckerImpl.h"
16 #include "Targets/RuntimeDyldELFMips.h"
17 #include "llvm/ADT/IntervalMap.h"
18 #include "llvm/ADT/STLExtras.h"
19 #include "llvm/ADT/StringRef.h"
20 #include "llvm/ADT/Triple.h"
21 #include "llvm/MC/MCStreamer.h"
22 #include "llvm/Object/ELFObjectFile.h"
23 #include "llvm/Object/ObjectFile.h"
24 #include "llvm/Support/ELF.h"
25 #include "llvm/Support/Endian.h"
26 #include "llvm/Support/MemoryBuffer.h"
27 #include "llvm/Support/TargetRegistry.h"
30 using namespace llvm::object;
31 using namespace llvm::support::endian;
33 #define DEBUG_TYPE "dyld"
35 static void or32le(void *P, int32_t V) { write32le(P, read32le(P) | V); }
37 static void or32AArch64Imm(void *L, uint64_t Imm) {
38 or32le(L, (Imm & 0xFFF) << 10);
41 template <class T> static void write(bool isBE, void *P, T V) {
42 isBE ? write<T, support::big>(P, V) : write<T, support::little>(P, V);
45 static void write32AArch64Addr(void *L, uint64_t Imm) {
46 uint32_t ImmLo = (Imm & 0x3) << 29;
47 uint32_t ImmHi = (Imm & 0x1FFFFC) << 3;
48 uint64_t Mask = (0x3 << 29) | (0x1FFFFC << 3);
49 write32le(L, (read32le(L) & ~Mask) | ImmLo | ImmHi);
52 // Return the bits [Start, End] from Val shifted Start bits.
53 // For instance, getBits(0xF0, 4, 8) returns 0xF.
54 static uint64_t getBits(uint64_t Val, int Start, int End) {
55 uint64_t Mask = ((uint64_t)1 << (End + 1 - Start)) - 1;
56 return (Val >> Start) & Mask;
61 template <class ELFT> class DyldELFObject : public ELFObjectFile<ELFT> {
62 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT)
64 typedef Elf_Shdr_Impl<ELFT> Elf_Shdr;
65 typedef Elf_Sym_Impl<ELFT> Elf_Sym;
66 typedef Elf_Rel_Impl<ELFT, false> Elf_Rel;
67 typedef Elf_Rel_Impl<ELFT, true> Elf_Rela;
69 typedef Elf_Ehdr_Impl<ELFT> Elf_Ehdr;
71 typedef typename ELFDataTypeTypedefHelper<ELFT>::value_type addr_type;
74 DyldELFObject(MemoryBufferRef Wrapper, std::error_code &ec);
76 void updateSectionAddress(const SectionRef &Sec, uint64_t Addr);
78 void updateSymbolAddress(const SymbolRef &SymRef, uint64_t Addr);
80 // Methods for type inquiry through isa, cast and dyn_cast
81 static inline bool classof(const Binary *v) {
82 return (isa<ELFObjectFile<ELFT>>(v) &&
83 classof(cast<ELFObjectFile<ELFT>>(v)));
85 static inline bool classof(const ELFObjectFile<ELFT> *v) {
86 return v->isDyldType();
92 // The MemoryBuffer passed into this constructor is just a wrapper around the
93 // actual memory. Ultimately, the Binary parent class will take ownership of
94 // this MemoryBuffer object but not the underlying memory.
96 DyldELFObject<ELFT>::DyldELFObject(MemoryBufferRef Wrapper, std::error_code &EC)
97 : ELFObjectFile<ELFT>(Wrapper, EC) {
98 this->isDyldELFObject = true;
101 template <class ELFT>
102 void DyldELFObject<ELFT>::updateSectionAddress(const SectionRef &Sec,
104 DataRefImpl ShdrRef = Sec.getRawDataRefImpl();
106 const_cast<Elf_Shdr *>(reinterpret_cast<const Elf_Shdr *>(ShdrRef.p));
108 // This assumes the address passed in matches the target address bitness
109 // The template-based type cast handles everything else.
110 shdr->sh_addr = static_cast<addr_type>(Addr);
113 template <class ELFT>
114 void DyldELFObject<ELFT>::updateSymbolAddress(const SymbolRef &SymRef,
117 Elf_Sym *sym = const_cast<Elf_Sym *>(
118 ELFObjectFile<ELFT>::getSymbol(SymRef.getRawDataRefImpl()));
120 // This assumes the address passed in matches the target address bitness
121 // The template-based type cast handles everything else.
122 sym->st_value = static_cast<addr_type>(Addr);
125 class LoadedELFObjectInfo final
126 : public RuntimeDyld::LoadedObjectInfoHelper<LoadedELFObjectInfo> {
128 LoadedELFObjectInfo(RuntimeDyldImpl &RTDyld, ObjSectionToIDMap ObjSecToIDMap)
129 : LoadedObjectInfoHelper(RTDyld, std::move(ObjSecToIDMap)) {}
131 OwningBinary<ObjectFile>
132 getObjectForDebug(const ObjectFile &Obj) const override;
135 template <typename ELFT>
136 std::unique_ptr<DyldELFObject<ELFT>>
137 createRTDyldELFObject(MemoryBufferRef Buffer,
138 const ObjectFile &SourceObject,
139 const LoadedELFObjectInfo &L,
140 std::error_code &ec) {
141 typedef typename ELFFile<ELFT>::Elf_Shdr Elf_Shdr;
142 typedef typename ELFDataTypeTypedefHelper<ELFT>::value_type addr_type;
144 std::unique_ptr<DyldELFObject<ELFT>> Obj =
145 llvm::make_unique<DyldELFObject<ELFT>>(Buffer, ec);
147 // Iterate over all sections in the object.
148 auto SI = SourceObject.section_begin();
149 for (const auto &Sec : Obj->sections()) {
150 StringRef SectionName;
151 Sec.getName(SectionName);
152 if (SectionName != "") {
153 DataRefImpl ShdrRef = Sec.getRawDataRefImpl();
154 Elf_Shdr *shdr = const_cast<Elf_Shdr *>(
155 reinterpret_cast<const Elf_Shdr *>(ShdrRef.p));
157 if (uint64_t SecLoadAddr = L.getSectionLoadAddress(*SI)) {
158 // This assumes that the address passed in matches the target address
159 // bitness. The template-based type cast handles everything else.
160 shdr->sh_addr = static_cast<addr_type>(SecLoadAddr);
169 OwningBinary<ObjectFile> createELFDebugObject(const ObjectFile &Obj,
170 const LoadedELFObjectInfo &L) {
171 assert(Obj.isELF() && "Not an ELF object file.");
173 std::unique_ptr<MemoryBuffer> Buffer =
174 MemoryBuffer::getMemBufferCopy(Obj.getData(), Obj.getFileName());
178 std::unique_ptr<ObjectFile> DebugObj;
179 if (Obj.getBytesInAddress() == 4 && Obj.isLittleEndian()) {
180 typedef ELFType<support::little, false> ELF32LE;
181 DebugObj = createRTDyldELFObject<ELF32LE>(Buffer->getMemBufferRef(), Obj, L,
183 } else if (Obj.getBytesInAddress() == 4 && !Obj.isLittleEndian()) {
184 typedef ELFType<support::big, false> ELF32BE;
185 DebugObj = createRTDyldELFObject<ELF32BE>(Buffer->getMemBufferRef(), Obj, L,
187 } else if (Obj.getBytesInAddress() == 8 && !Obj.isLittleEndian()) {
188 typedef ELFType<support::big, true> ELF64BE;
189 DebugObj = createRTDyldELFObject<ELF64BE>(Buffer->getMemBufferRef(), Obj, L,
191 } else if (Obj.getBytesInAddress() == 8 && Obj.isLittleEndian()) {
192 typedef ELFType<support::little, true> ELF64LE;
193 DebugObj = createRTDyldELFObject<ELF64LE>(Buffer->getMemBufferRef(), Obj, L,
196 llvm_unreachable("Unexpected ELF format");
198 assert(!ec && "Could not construct copy ELF object file");
200 return OwningBinary<ObjectFile>(std::move(DebugObj), std::move(Buffer));
203 OwningBinary<ObjectFile>
204 LoadedELFObjectInfo::getObjectForDebug(const ObjectFile &Obj) const {
205 return createELFDebugObject(Obj, *this);
208 } // anonymous namespace
212 RuntimeDyldELF::RuntimeDyldELF(RuntimeDyld::MemoryManager &MemMgr,
213 JITSymbolResolver &Resolver)
214 : RuntimeDyldImpl(MemMgr, Resolver), GOTSectionID(0), CurrentGOTIndex(0) {}
215 RuntimeDyldELF::~RuntimeDyldELF() {}
217 void RuntimeDyldELF::registerEHFrames() {
218 for (int i = 0, e = UnregisteredEHFrameSections.size(); i != e; ++i) {
219 SID EHFrameSID = UnregisteredEHFrameSections[i];
220 uint8_t *EHFrameAddr = Sections[EHFrameSID].getAddress();
221 uint64_t EHFrameLoadAddr = Sections[EHFrameSID].getLoadAddress();
222 size_t EHFrameSize = Sections[EHFrameSID].getSize();
223 MemMgr.registerEHFrames(EHFrameAddr, EHFrameLoadAddr, EHFrameSize);
224 RegisteredEHFrameSections.push_back(EHFrameSID);
226 UnregisteredEHFrameSections.clear();
229 void RuntimeDyldELF::deregisterEHFrames() {
230 for (int i = 0, e = RegisteredEHFrameSections.size(); i != e; ++i) {
231 SID EHFrameSID = RegisteredEHFrameSections[i];
232 uint8_t *EHFrameAddr = Sections[EHFrameSID].getAddress();
233 uint64_t EHFrameLoadAddr = Sections[EHFrameSID].getLoadAddress();
234 size_t EHFrameSize = Sections[EHFrameSID].getSize();
235 MemMgr.deregisterEHFrames(EHFrameAddr, EHFrameLoadAddr, EHFrameSize);
237 RegisteredEHFrameSections.clear();
240 std::unique_ptr<RuntimeDyldELF>
241 llvm::RuntimeDyldELF::create(Triple::ArchType Arch,
242 RuntimeDyld::MemoryManager &MemMgr,
243 JITSymbolResolver &Resolver) {
246 return make_unique<RuntimeDyldELF>(MemMgr, Resolver);
250 case Triple::mips64el:
251 return make_unique<RuntimeDyldELFMips>(MemMgr, Resolver);
255 std::unique_ptr<RuntimeDyld::LoadedObjectInfo>
256 RuntimeDyldELF::loadObject(const object::ObjectFile &O) {
257 if (auto ObjSectionToIDOrErr = loadObjectImpl(O))
258 return llvm::make_unique<LoadedELFObjectInfo>(*this, *ObjSectionToIDOrErr);
261 raw_string_ostream ErrStream(ErrorStr);
262 logAllUnhandledErrors(ObjSectionToIDOrErr.takeError(), ErrStream, "");
267 void RuntimeDyldELF::resolveX86_64Relocation(const SectionEntry &Section,
268 uint64_t Offset, uint64_t Value,
269 uint32_t Type, int64_t Addend,
270 uint64_t SymOffset) {
273 llvm_unreachable("Relocation type not implemented yet!");
275 case ELF::R_X86_64_NONE:
277 case ELF::R_X86_64_64: {
278 support::ulittle64_t::ref(Section.getAddressWithOffset(Offset)) =
280 DEBUG(dbgs() << "Writing " << format("%p", (Value + Addend)) << " at "
281 << format("%p\n", Section.getAddressWithOffset(Offset)));
284 case ELF::R_X86_64_32:
285 case ELF::R_X86_64_32S: {
287 assert((Type == ELF::R_X86_64_32 && (Value <= UINT32_MAX)) ||
288 (Type == ELF::R_X86_64_32S &&
289 ((int64_t)Value <= INT32_MAX && (int64_t)Value >= INT32_MIN)));
290 uint32_t TruncatedAddr = (Value & 0xFFFFFFFF);
291 support::ulittle32_t::ref(Section.getAddressWithOffset(Offset)) =
293 DEBUG(dbgs() << "Writing " << format("%p", TruncatedAddr) << " at "
294 << format("%p\n", Section.getAddressWithOffset(Offset)));
297 case ELF::R_X86_64_PC8: {
298 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
299 int64_t RealOffset = Value + Addend - FinalAddress;
300 assert(isInt<8>(RealOffset));
301 int8_t TruncOffset = (RealOffset & 0xFF);
302 Section.getAddress()[Offset] = TruncOffset;
305 case ELF::R_X86_64_PC32: {
306 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
307 int64_t RealOffset = Value + Addend - FinalAddress;
308 assert(isInt<32>(RealOffset));
309 int32_t TruncOffset = (RealOffset & 0xFFFFFFFF);
310 support::ulittle32_t::ref(Section.getAddressWithOffset(Offset)) =
314 case ELF::R_X86_64_PC64: {
315 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
316 int64_t RealOffset = Value + Addend - FinalAddress;
317 support::ulittle64_t::ref(Section.getAddressWithOffset(Offset)) =
324 void RuntimeDyldELF::resolveX86Relocation(const SectionEntry &Section,
325 uint64_t Offset, uint32_t Value,
326 uint32_t Type, int32_t Addend) {
328 case ELF::R_386_32: {
329 support::ulittle32_t::ref(Section.getAddressWithOffset(Offset)) =
333 case ELF::R_386_PC32: {
334 uint32_t FinalAddress =
335 Section.getLoadAddressWithOffset(Offset) & 0xFFFFFFFF;
336 uint32_t RealOffset = Value + Addend - FinalAddress;
337 support::ulittle32_t::ref(Section.getAddressWithOffset(Offset)) =
342 // There are other relocation types, but it appears these are the
343 // only ones currently used by the LLVM ELF object writer
344 llvm_unreachable("Relocation type not implemented yet!");
349 void RuntimeDyldELF::resolveAArch64Relocation(const SectionEntry &Section,
350 uint64_t Offset, uint64_t Value,
351 uint32_t Type, int64_t Addend) {
352 uint32_t *TargetPtr =
353 reinterpret_cast<uint32_t *>(Section.getAddressWithOffset(Offset));
354 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
355 // Data should use target endian. Code should always use little endian.
356 bool isBE = Arch == Triple::aarch64_be;
358 DEBUG(dbgs() << "resolveAArch64Relocation, LocalAddress: 0x"
359 << format("%llx", Section.getAddressWithOffset(Offset))
360 << " FinalAddress: 0x" << format("%llx", FinalAddress)
361 << " Value: 0x" << format("%llx", Value) << " Type: 0x"
362 << format("%x", Type) << " Addend: 0x" << format("%llx", Addend)
367 llvm_unreachable("Relocation type not implemented yet!");
369 case ELF::R_AARCH64_ABS64:
370 write(isBE, TargetPtr, Value + Addend);
372 case ELF::R_AARCH64_PREL32: {
373 uint64_t Result = Value + Addend - FinalAddress;
374 assert(static_cast<int64_t>(Result) >= INT32_MIN &&
375 static_cast<int64_t>(Result) <= UINT32_MAX);
376 write(isBE, TargetPtr, static_cast<uint32_t>(Result & 0xffffffffU));
379 case ELF::R_AARCH64_PREL64:
380 write(isBE, TargetPtr, Value + Addend - FinalAddress);
382 case ELF::R_AARCH64_CALL26: // fallthrough
383 case ELF::R_AARCH64_JUMP26: {
384 // Operation: S+A-P. Set Call or B immediate value to bits fff_fffc of the
386 uint64_t BranchImm = Value + Addend - FinalAddress;
388 // "Check that -2^27 <= result < 2^27".
389 assert(isInt<28>(BranchImm));
390 or32le(TargetPtr, (BranchImm & 0x0FFFFFFC) >> 2);
393 case ELF::R_AARCH64_MOVW_UABS_G3:
394 or32le(TargetPtr, ((Value + Addend) & 0xFFFF000000000000) >> 43);
396 case ELF::R_AARCH64_MOVW_UABS_G2_NC:
397 or32le(TargetPtr, ((Value + Addend) & 0xFFFF00000000) >> 27);
399 case ELF::R_AARCH64_MOVW_UABS_G1_NC:
400 or32le(TargetPtr, ((Value + Addend) & 0xFFFF0000) >> 11);
402 case ELF::R_AARCH64_MOVW_UABS_G0_NC:
403 or32le(TargetPtr, ((Value + Addend) & 0xFFFF) << 5);
405 case ELF::R_AARCH64_ADR_PREL_PG_HI21: {
406 // Operation: Page(S+A) - Page(P)
408 ((Value + Addend) & ~0xfffULL) - (FinalAddress & ~0xfffULL);
410 // Check that -2^32 <= X < 2^32
411 assert(isInt<33>(Result) && "overflow check failed for relocation");
413 // Immediate goes in bits 30:29 + 5:23 of ADRP instruction, taken
414 // from bits 32:12 of X.
415 write32AArch64Addr(TargetPtr, Result >> 12);
418 case ELF::R_AARCH64_ADD_ABS_LO12_NC:
420 // Immediate goes in bits 21:10 of LD/ST instruction, taken
421 // from bits 11:0 of X
422 or32AArch64Imm(TargetPtr, Value + Addend);
424 case ELF::R_AARCH64_LDST8_ABS_LO12_NC:
426 // Immediate goes in bits 21:10 of LD/ST instruction, taken
427 // from bits 11:0 of X
428 or32AArch64Imm(TargetPtr, getBits(Value + Addend, 0, 11));
430 case ELF::R_AARCH64_LDST16_ABS_LO12_NC:
432 // Immediate goes in bits 21:10 of LD/ST instruction, taken
433 // from bits 11:1 of X
434 or32AArch64Imm(TargetPtr, getBits(Value + Addend, 1, 11));
436 case ELF::R_AARCH64_LDST32_ABS_LO12_NC:
438 // Immediate goes in bits 21:10 of LD/ST instruction, taken
439 // from bits 11:2 of X
440 or32AArch64Imm(TargetPtr, getBits(Value + Addend, 2, 11));
442 case ELF::R_AARCH64_LDST64_ABS_LO12_NC:
444 // Immediate goes in bits 21:10 of LD/ST instruction, taken
445 // from bits 11:3 of X
446 or32AArch64Imm(TargetPtr, getBits(Value + Addend, 3, 11));
448 case ELF::R_AARCH64_LDST128_ABS_LO12_NC:
450 // Immediate goes in bits 21:10 of LD/ST instruction, taken
451 // from bits 11:4 of X
452 or32AArch64Imm(TargetPtr, getBits(Value + Addend, 4, 11));
457 void RuntimeDyldELF::resolveARMRelocation(const SectionEntry &Section,
458 uint64_t Offset, uint32_t Value,
459 uint32_t Type, int32_t Addend) {
460 // TODO: Add Thumb relocations.
461 uint32_t *TargetPtr =
462 reinterpret_cast<uint32_t *>(Section.getAddressWithOffset(Offset));
463 uint32_t FinalAddress = Section.getLoadAddressWithOffset(Offset) & 0xFFFFFFFF;
466 DEBUG(dbgs() << "resolveARMRelocation, LocalAddress: "
467 << Section.getAddressWithOffset(Offset)
468 << " FinalAddress: " << format("%p", FinalAddress) << " Value: "
469 << format("%x", Value) << " Type: " << format("%x", Type)
470 << " Addend: " << format("%x", Addend) << "\n");
474 llvm_unreachable("Not implemented relocation type!");
476 case ELF::R_ARM_NONE:
478 // Write a 31bit signed offset
479 case ELF::R_ARM_PREL31:
480 support::ulittle32_t::ref{TargetPtr} =
481 (support::ulittle32_t::ref{TargetPtr} & 0x80000000) |
482 ((Value - FinalAddress) & ~0x80000000);
484 case ELF::R_ARM_TARGET1:
485 case ELF::R_ARM_ABS32:
486 support::ulittle32_t::ref{TargetPtr} = Value;
488 // Write first 16 bit of 32 bit value to the mov instruction.
489 // Last 4 bit should be shifted.
490 case ELF::R_ARM_MOVW_ABS_NC:
491 case ELF::R_ARM_MOVT_ABS:
492 if (Type == ELF::R_ARM_MOVW_ABS_NC)
493 Value = Value & 0xFFFF;
494 else if (Type == ELF::R_ARM_MOVT_ABS)
495 Value = (Value >> 16) & 0xFFFF;
496 support::ulittle32_t::ref{TargetPtr} =
497 (support::ulittle32_t::ref{TargetPtr} & ~0x000F0FFF) | (Value & 0xFFF) |
498 (((Value >> 12) & 0xF) << 16);
500 // Write 24 bit relative value to the branch instruction.
501 case ELF::R_ARM_PC24: // Fall through.
502 case ELF::R_ARM_CALL: // Fall through.
503 case ELF::R_ARM_JUMP24:
504 int32_t RelValue = static_cast<int32_t>(Value - FinalAddress - 8);
505 RelValue = (RelValue & 0x03FFFFFC) >> 2;
506 assert((support::ulittle32_t::ref{TargetPtr} & 0xFFFFFF) == 0xFFFFFE);
507 support::ulittle32_t::ref{TargetPtr} =
508 (support::ulittle32_t::ref{TargetPtr} & 0xFF000000) | RelValue;
513 void RuntimeDyldELF::setMipsABI(const ObjectFile &Obj) {
514 if (Arch == Triple::UnknownArch ||
515 !StringRef(Triple::getArchTypePrefix(Arch)).equals("mips")) {
516 IsMipsO32ABI = false;
517 IsMipsN32ABI = false;
518 IsMipsN64ABI = false;
522 Obj.getPlatformFlags(AbiVariant);
523 IsMipsO32ABI = AbiVariant & ELF::EF_MIPS_ABI_O32;
524 IsMipsN32ABI = AbiVariant & ELF::EF_MIPS_ABI2;
525 IsMipsN64ABI = Obj.getFileFormatName().equals("ELF64-mips");
528 // Return the .TOC. section and offset.
529 Error RuntimeDyldELF::findPPC64TOCSection(const ELFObjectFileBase &Obj,
530 ObjSectionToIDMap &LocalSections,
531 RelocationValueRef &Rel) {
532 // Set a default SectionID in case we do not find a TOC section below.
533 // This may happen for references to TOC base base (sym@toc, .odp
534 // relocation) without a .toc directive. In this case just use the
535 // first section (which is usually the .odp) since the code won't
536 // reference the .toc base directly.
537 Rel.SymbolName = nullptr;
540 // The TOC consists of sections .got, .toc, .tocbss, .plt in that
541 // order. The TOC starts where the first of these sections starts.
542 for (auto &Section: Obj.sections()) {
543 StringRef SectionName;
544 if (auto EC = Section.getName(SectionName))
545 return errorCodeToError(EC);
547 if (SectionName == ".got"
548 || SectionName == ".toc"
549 || SectionName == ".tocbss"
550 || SectionName == ".plt") {
551 if (auto SectionIDOrErr =
552 findOrEmitSection(Obj, Section, false, LocalSections))
553 Rel.SectionID = *SectionIDOrErr;
555 return SectionIDOrErr.takeError();
560 // Per the ppc64-elf-linux ABI, The TOC base is TOC value plus 0x8000
561 // thus permitting a full 64 Kbytes segment.
564 return Error::success();
567 // Returns the sections and offset associated with the ODP entry referenced
569 Error RuntimeDyldELF::findOPDEntrySection(const ELFObjectFileBase &Obj,
570 ObjSectionToIDMap &LocalSections,
571 RelocationValueRef &Rel) {
572 // Get the ELF symbol value (st_value) to compare with Relocation offset in
574 for (section_iterator si = Obj.section_begin(), se = Obj.section_end();
576 section_iterator RelSecI = si->getRelocatedSection();
577 if (RelSecI == Obj.section_end())
580 StringRef RelSectionName;
581 if (auto EC = RelSecI->getName(RelSectionName))
582 return errorCodeToError(EC);
584 if (RelSectionName != ".opd")
587 for (elf_relocation_iterator i = si->relocation_begin(),
588 e = si->relocation_end();
590 // The R_PPC64_ADDR64 relocation indicates the first field
592 uint64_t TypeFunc = i->getType();
593 if (TypeFunc != ELF::R_PPC64_ADDR64) {
598 uint64_t TargetSymbolOffset = i->getOffset();
599 symbol_iterator TargetSymbol = i->getSymbol();
601 if (auto AddendOrErr = i->getAddend())
602 Addend = *AddendOrErr;
604 return errorCodeToError(AddendOrErr.getError());
610 // Just check if following relocation is a R_PPC64_TOC
611 uint64_t TypeTOC = i->getType();
612 if (TypeTOC != ELF::R_PPC64_TOC)
615 // Finally compares the Symbol value and the target symbol offset
616 // to check if this .opd entry refers to the symbol the relocation
618 if (Rel.Addend != (int64_t)TargetSymbolOffset)
621 section_iterator TSI = Obj.section_end();
622 if (auto TSIOrErr = TargetSymbol->getSection())
625 return TSIOrErr.takeError();
626 assert(TSI != Obj.section_end() && "TSI should refer to a valid section");
628 bool IsCode = TSI->isText();
629 if (auto SectionIDOrErr = findOrEmitSection(Obj, *TSI, IsCode,
631 Rel.SectionID = *SectionIDOrErr;
633 return SectionIDOrErr.takeError();
634 Rel.Addend = (intptr_t)Addend;
635 return Error::success();
638 llvm_unreachable("Attempting to get address of ODP entry!");
641 // Relocation masks following the #lo(value), #hi(value), #ha(value),
642 // #higher(value), #highera(value), #highest(value), and #highesta(value)
643 // macros defined in section 4.5.1. Relocation Types of the PPC-elf64abi
646 static inline uint16_t applyPPClo(uint64_t value) { return value & 0xffff; }
648 static inline uint16_t applyPPChi(uint64_t value) {
649 return (value >> 16) & 0xffff;
652 static inline uint16_t applyPPCha (uint64_t value) {
653 return ((value + 0x8000) >> 16) & 0xffff;
656 static inline uint16_t applyPPChigher(uint64_t value) {
657 return (value >> 32) & 0xffff;
660 static inline uint16_t applyPPChighera (uint64_t value) {
661 return ((value + 0x8000) >> 32) & 0xffff;
664 static inline uint16_t applyPPChighest(uint64_t value) {
665 return (value >> 48) & 0xffff;
668 static inline uint16_t applyPPChighesta (uint64_t value) {
669 return ((value + 0x8000) >> 48) & 0xffff;
672 void RuntimeDyldELF::resolvePPC32Relocation(const SectionEntry &Section,
673 uint64_t Offset, uint64_t Value,
674 uint32_t Type, int64_t Addend) {
675 uint8_t *LocalAddress = Section.getAddressWithOffset(Offset);
678 llvm_unreachable("Relocation type not implemented yet!");
680 case ELF::R_PPC_ADDR16_LO:
681 writeInt16BE(LocalAddress, applyPPClo(Value + Addend));
683 case ELF::R_PPC_ADDR16_HI:
684 writeInt16BE(LocalAddress, applyPPChi(Value + Addend));
686 case ELF::R_PPC_ADDR16_HA:
687 writeInt16BE(LocalAddress, applyPPCha(Value + Addend));
692 void RuntimeDyldELF::resolvePPC64Relocation(const SectionEntry &Section,
693 uint64_t Offset, uint64_t Value,
694 uint32_t Type, int64_t Addend) {
695 uint8_t *LocalAddress = Section.getAddressWithOffset(Offset);
698 llvm_unreachable("Relocation type not implemented yet!");
700 case ELF::R_PPC64_ADDR16:
701 writeInt16BE(LocalAddress, applyPPClo(Value + Addend));
703 case ELF::R_PPC64_ADDR16_DS:
704 writeInt16BE(LocalAddress, applyPPClo(Value + Addend) & ~3);
706 case ELF::R_PPC64_ADDR16_LO:
707 writeInt16BE(LocalAddress, applyPPClo(Value + Addend));
709 case ELF::R_PPC64_ADDR16_LO_DS:
710 writeInt16BE(LocalAddress, applyPPClo(Value + Addend) & ~3);
712 case ELF::R_PPC64_ADDR16_HI:
713 writeInt16BE(LocalAddress, applyPPChi(Value + Addend));
715 case ELF::R_PPC64_ADDR16_HA:
716 writeInt16BE(LocalAddress, applyPPCha(Value + Addend));
718 case ELF::R_PPC64_ADDR16_HIGHER:
719 writeInt16BE(LocalAddress, applyPPChigher(Value + Addend));
721 case ELF::R_PPC64_ADDR16_HIGHERA:
722 writeInt16BE(LocalAddress, applyPPChighera(Value + Addend));
724 case ELF::R_PPC64_ADDR16_HIGHEST:
725 writeInt16BE(LocalAddress, applyPPChighest(Value + Addend));
727 case ELF::R_PPC64_ADDR16_HIGHESTA:
728 writeInt16BE(LocalAddress, applyPPChighesta(Value + Addend));
730 case ELF::R_PPC64_ADDR14: {
731 assert(((Value + Addend) & 3) == 0);
732 // Preserve the AA/LK bits in the branch instruction
733 uint8_t aalk = *(LocalAddress + 3);
734 writeInt16BE(LocalAddress + 2, (aalk & 3) | ((Value + Addend) & 0xfffc));
736 case ELF::R_PPC64_REL16_LO: {
737 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
738 uint64_t Delta = Value - FinalAddress + Addend;
739 writeInt16BE(LocalAddress, applyPPClo(Delta));
741 case ELF::R_PPC64_REL16_HI: {
742 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
743 uint64_t Delta = Value - FinalAddress + Addend;
744 writeInt16BE(LocalAddress, applyPPChi(Delta));
746 case ELF::R_PPC64_REL16_HA: {
747 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
748 uint64_t Delta = Value - FinalAddress + Addend;
749 writeInt16BE(LocalAddress, applyPPCha(Delta));
751 case ELF::R_PPC64_ADDR32: {
752 int32_t Result = static_cast<int32_t>(Value + Addend);
753 if (SignExtend32<32>(Result) != Result)
754 llvm_unreachable("Relocation R_PPC64_ADDR32 overflow");
755 writeInt32BE(LocalAddress, Result);
757 case ELF::R_PPC64_REL24: {
758 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
759 int32_t delta = static_cast<int32_t>(Value - FinalAddress + Addend);
760 if (SignExtend32<26>(delta) != delta)
761 llvm_unreachable("Relocation R_PPC64_REL24 overflow");
762 // Generates a 'bl <address>' instruction
763 writeInt32BE(LocalAddress, 0x48000001 | (delta & 0x03FFFFFC));
765 case ELF::R_PPC64_REL32: {
766 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
767 int32_t delta = static_cast<int32_t>(Value - FinalAddress + Addend);
768 if (SignExtend32<32>(delta) != delta)
769 llvm_unreachable("Relocation R_PPC64_REL32 overflow");
770 writeInt32BE(LocalAddress, delta);
772 case ELF::R_PPC64_REL64: {
773 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
774 uint64_t Delta = Value - FinalAddress + Addend;
775 writeInt64BE(LocalAddress, Delta);
777 case ELF::R_PPC64_ADDR64:
778 writeInt64BE(LocalAddress, Value + Addend);
783 void RuntimeDyldELF::resolveSystemZRelocation(const SectionEntry &Section,
784 uint64_t Offset, uint64_t Value,
785 uint32_t Type, int64_t Addend) {
786 uint8_t *LocalAddress = Section.getAddressWithOffset(Offset);
789 llvm_unreachable("Relocation type not implemented yet!");
791 case ELF::R_390_PC16DBL:
792 case ELF::R_390_PLT16DBL: {
793 int64_t Delta = (Value + Addend) - Section.getLoadAddressWithOffset(Offset);
794 assert(int16_t(Delta / 2) * 2 == Delta && "R_390_PC16DBL overflow");
795 writeInt16BE(LocalAddress, Delta / 2);
798 case ELF::R_390_PC32DBL:
799 case ELF::R_390_PLT32DBL: {
800 int64_t Delta = (Value + Addend) - Section.getLoadAddressWithOffset(Offset);
801 assert(int32_t(Delta / 2) * 2 == Delta && "R_390_PC32DBL overflow");
802 writeInt32BE(LocalAddress, Delta / 2);
805 case ELF::R_390_PC32: {
806 int64_t Delta = (Value + Addend) - Section.getLoadAddressWithOffset(Offset);
807 assert(int32_t(Delta) == Delta && "R_390_PC32 overflow");
808 writeInt32BE(LocalAddress, Delta);
812 writeInt64BE(LocalAddress, Value + Addend);
814 case ELF::R_390_PC64: {
815 int64_t Delta = (Value + Addend) - Section.getLoadAddressWithOffset(Offset);
816 writeInt64BE(LocalAddress, Delta);
822 // The target location for the relocation is described by RE.SectionID and
823 // RE.Offset. RE.SectionID can be used to find the SectionEntry. Each
824 // SectionEntry has three members describing its location.
825 // SectionEntry::Address is the address at which the section has been loaded
826 // into memory in the current (host) process. SectionEntry::LoadAddress is the
827 // address that the section will have in the target process.
828 // SectionEntry::ObjAddress is the address of the bits for this section in the
829 // original emitted object image (also in the current address space).
831 // Relocations will be applied as if the section were loaded at
832 // SectionEntry::LoadAddress, but they will be applied at an address based
833 // on SectionEntry::Address. SectionEntry::ObjAddress will be used to refer to
834 // Target memory contents if they are required for value calculations.
836 // The Value parameter here is the load address of the symbol for the
837 // relocation to be applied. For relocations which refer to symbols in the
838 // current object Value will be the LoadAddress of the section in which
839 // the symbol resides (RE.Addend provides additional information about the
840 // symbol location). For external symbols, Value will be the address of the
841 // symbol in the target address space.
842 void RuntimeDyldELF::resolveRelocation(const RelocationEntry &RE,
844 const SectionEntry &Section = Sections[RE.SectionID];
845 return resolveRelocation(Section, RE.Offset, Value, RE.RelType, RE.Addend,
846 RE.SymOffset, RE.SectionID);
849 void RuntimeDyldELF::resolveRelocation(const SectionEntry &Section,
850 uint64_t Offset, uint64_t Value,
851 uint32_t Type, int64_t Addend,
852 uint64_t SymOffset, SID SectionID) {
855 resolveX86_64Relocation(Section, Offset, Value, Type, Addend, SymOffset);
858 resolveX86Relocation(Section, Offset, (uint32_t)(Value & 0xffffffffL), Type,
859 (uint32_t)(Addend & 0xffffffffL));
861 case Triple::aarch64:
862 case Triple::aarch64_be:
863 resolveAArch64Relocation(Section, Offset, Value, Type, Addend);
865 case Triple::arm: // Fall through.
868 case Triple::thumbeb:
869 resolveARMRelocation(Section, Offset, (uint32_t)(Value & 0xffffffffL), Type,
870 (uint32_t)(Addend & 0xffffffffL));
873 resolvePPC32Relocation(Section, Offset, Value, Type, Addend);
875 case Triple::ppc64: // Fall through.
876 case Triple::ppc64le:
877 resolvePPC64Relocation(Section, Offset, Value, Type, Addend);
879 case Triple::systemz:
880 resolveSystemZRelocation(Section, Offset, Value, Type, Addend);
883 llvm_unreachable("Unsupported CPU type!");
887 void *RuntimeDyldELF::computePlaceholderAddress(unsigned SectionID, uint64_t Offset) const {
888 return (void *)(Sections[SectionID].getObjAddress() + Offset);
891 void RuntimeDyldELF::processSimpleRelocation(unsigned SectionID, uint64_t Offset, unsigned RelType, RelocationValueRef Value) {
892 RelocationEntry RE(SectionID, Offset, RelType, Value.Addend, Value.Offset);
893 if (Value.SymbolName)
894 addRelocationForSymbol(RE, Value.SymbolName);
896 addRelocationForSection(RE, Value.SectionID);
899 uint32_t RuntimeDyldELF::getMatchingLoRelocation(uint32_t RelType,
900 bool IsLocal) const {
902 case ELF::R_MICROMIPS_GOT16:
904 return ELF::R_MICROMIPS_LO16;
906 case ELF::R_MICROMIPS_HI16:
907 return ELF::R_MICROMIPS_LO16;
908 case ELF::R_MIPS_GOT16:
910 return ELF::R_MIPS_LO16;
912 case ELF::R_MIPS_HI16:
913 return ELF::R_MIPS_LO16;
914 case ELF::R_MIPS_PCHI16:
915 return ELF::R_MIPS_PCLO16;
919 return ELF::R_MIPS_NONE;
922 // Sometimes we don't need to create thunk for a branch.
923 // This typically happens when branch target is located
924 // in the same object file. In such case target is either
925 // a weak symbol or symbol in a different executable section.
926 // This function checks if branch target is located in the
927 // same object file and if distance between source and target
928 // fits R_AARCH64_CALL26 relocation. If both conditions are
929 // met, it emits direct jump to the target and returns true.
930 // Otherwise false is returned and thunk is created.
931 bool RuntimeDyldELF::resolveAArch64ShortBranch(
932 unsigned SectionID, relocation_iterator RelI,
933 const RelocationValueRef &Value) {
935 if (Value.SymbolName) {
936 auto Loc = GlobalSymbolTable.find(Value.SymbolName);
938 // Don't create direct branch for external symbols.
939 if (Loc == GlobalSymbolTable.end())
942 const auto &SymInfo = Loc->second;
944 uint64_t(Sections[SymInfo.getSectionID()].getLoadAddressWithOffset(
945 SymInfo.getOffset()));
947 Address = uint64_t(Sections[Value.SectionID].getLoadAddress());
949 uint64_t Offset = RelI->getOffset();
950 uint64_t SourceAddress = Sections[SectionID].getLoadAddressWithOffset(Offset);
952 // R_AARCH64_CALL26 requires immediate to be in range -2^27 <= imm < 2^27
953 // If distance between source and target is out of range then we should
955 if (!isInt<28>(Address + Value.Addend - SourceAddress))
958 resolveRelocation(Sections[SectionID], Offset, Address, RelI->getType(),
964 void RuntimeDyldELF::resolveAArch64Branch(unsigned SectionID,
965 const RelocationValueRef &Value,
966 relocation_iterator RelI,
969 DEBUG(dbgs() << "\t\tThis is an AArch64 branch relocation.");
970 SectionEntry &Section = Sections[SectionID];
972 uint64_t Offset = RelI->getOffset();
973 unsigned RelType = RelI->getType();
974 // Look for an existing stub.
975 StubMap::const_iterator i = Stubs.find(Value);
976 if (i != Stubs.end()) {
977 resolveRelocation(Section, Offset,
978 (uint64_t)Section.getAddressWithOffset(i->second),
980 DEBUG(dbgs() << " Stub function found\n");
981 } else if (!resolveAArch64ShortBranch(SectionID, RelI, Value)) {
982 // Create a new stub function.
983 DEBUG(dbgs() << " Create a new stub function\n");
984 Stubs[Value] = Section.getStubOffset();
985 uint8_t *StubTargetAddr = createStubFunction(
986 Section.getAddressWithOffset(Section.getStubOffset()));
988 RelocationEntry REmovz_g3(SectionID, StubTargetAddr - Section.getAddress(),
989 ELF::R_AARCH64_MOVW_UABS_G3, Value.Addend);
990 RelocationEntry REmovk_g2(SectionID,
991 StubTargetAddr - Section.getAddress() + 4,
992 ELF::R_AARCH64_MOVW_UABS_G2_NC, Value.Addend);
993 RelocationEntry REmovk_g1(SectionID,
994 StubTargetAddr - Section.getAddress() + 8,
995 ELF::R_AARCH64_MOVW_UABS_G1_NC, Value.Addend);
996 RelocationEntry REmovk_g0(SectionID,
997 StubTargetAddr - Section.getAddress() + 12,
998 ELF::R_AARCH64_MOVW_UABS_G0_NC, Value.Addend);
1000 if (Value.SymbolName) {
1001 addRelocationForSymbol(REmovz_g3, Value.SymbolName);
1002 addRelocationForSymbol(REmovk_g2, Value.SymbolName);
1003 addRelocationForSymbol(REmovk_g1, Value.SymbolName);
1004 addRelocationForSymbol(REmovk_g0, Value.SymbolName);
1006 addRelocationForSection(REmovz_g3, Value.SectionID);
1007 addRelocationForSection(REmovk_g2, Value.SectionID);
1008 addRelocationForSection(REmovk_g1, Value.SectionID);
1009 addRelocationForSection(REmovk_g0, Value.SectionID);
1011 resolveRelocation(Section, Offset,
1012 reinterpret_cast<uint64_t>(Section.getAddressWithOffset(
1013 Section.getStubOffset())),
1015 Section.advanceStubOffset(getMaxStubSize());
1019 Expected<relocation_iterator>
1020 RuntimeDyldELF::processRelocationRef(
1021 unsigned SectionID, relocation_iterator RelI, const ObjectFile &O,
1022 ObjSectionToIDMap &ObjSectionToID, StubMap &Stubs) {
1023 const auto &Obj = cast<ELFObjectFileBase>(O);
1024 uint64_t RelType = RelI->getType();
1025 ErrorOr<int64_t> AddendOrErr = ELFRelocationRef(*RelI).getAddend();
1026 int64_t Addend = AddendOrErr ? *AddendOrErr : 0;
1027 elf_symbol_iterator Symbol = RelI->getSymbol();
1029 // Obtain the symbol name which is referenced in the relocation
1030 StringRef TargetName;
1031 if (Symbol != Obj.symbol_end()) {
1032 if (auto TargetNameOrErr = Symbol->getName())
1033 TargetName = *TargetNameOrErr;
1035 return TargetNameOrErr.takeError();
1037 DEBUG(dbgs() << "\t\tRelType: " << RelType << " Addend: " << Addend
1038 << " TargetName: " << TargetName << "\n");
1039 RelocationValueRef Value;
1040 // First search for the symbol in the local symbol table
1041 SymbolRef::Type SymType = SymbolRef::ST_Unknown;
1043 // Search for the symbol in the global symbol table
1044 RTDyldSymbolTable::const_iterator gsi = GlobalSymbolTable.end();
1045 if (Symbol != Obj.symbol_end()) {
1046 gsi = GlobalSymbolTable.find(TargetName.data());
1047 Expected<SymbolRef::Type> SymTypeOrErr = Symbol->getType();
1048 if (!SymTypeOrErr) {
1050 raw_string_ostream OS(Buf);
1051 logAllUnhandledErrors(SymTypeOrErr.takeError(), OS, "");
1053 report_fatal_error(Buf);
1055 SymType = *SymTypeOrErr;
1057 if (gsi != GlobalSymbolTable.end()) {
1058 const auto &SymInfo = gsi->second;
1059 Value.SectionID = SymInfo.getSectionID();
1060 Value.Offset = SymInfo.getOffset();
1061 Value.Addend = SymInfo.getOffset() + Addend;
1064 case SymbolRef::ST_Debug: {
1065 // TODO: Now ELF SymbolRef::ST_Debug = STT_SECTION, it's not obviously
1066 // and can be changed by another developers. Maybe best way is add
1067 // a new symbol type ST_Section to SymbolRef and use it.
1068 auto SectionOrErr = Symbol->getSection();
1069 if (!SectionOrErr) {
1071 raw_string_ostream OS(Buf);
1072 logAllUnhandledErrors(SectionOrErr.takeError(), OS, "");
1074 report_fatal_error(Buf);
1076 section_iterator si = *SectionOrErr;
1077 if (si == Obj.section_end())
1078 llvm_unreachable("Symbol section not found, bad object file format!");
1079 DEBUG(dbgs() << "\t\tThis is section symbol\n");
1080 bool isCode = si->isText();
1081 if (auto SectionIDOrErr = findOrEmitSection(Obj, (*si), isCode,
1083 Value.SectionID = *SectionIDOrErr;
1085 return SectionIDOrErr.takeError();
1086 Value.Addend = Addend;
1089 case SymbolRef::ST_Data:
1090 case SymbolRef::ST_Function:
1091 case SymbolRef::ST_Unknown: {
1092 Value.SymbolName = TargetName.data();
1093 Value.Addend = Addend;
1095 // Absolute relocations will have a zero symbol ID (STN_UNDEF), which
1096 // will manifest here as a NULL symbol name.
1097 // We can set this as a valid (but empty) symbol name, and rely
1098 // on addRelocationForSymbol to handle this.
1099 if (!Value.SymbolName)
1100 Value.SymbolName = "";
1104 llvm_unreachable("Unresolved symbol type!");
1109 uint64_t Offset = RelI->getOffset();
1111 DEBUG(dbgs() << "\t\tSectionID: " << SectionID << " Offset: " << Offset
1113 if ((Arch == Triple::aarch64 || Arch == Triple::aarch64_be)) {
1114 if (RelType == ELF::R_AARCH64_CALL26 || RelType == ELF::R_AARCH64_JUMP26) {
1115 resolveAArch64Branch(SectionID, Value, RelI, Stubs);
1116 } else if (RelType == ELF::R_AARCH64_ADR_GOT_PAGE) {
1117 // Craete new GOT entry or find existing one. If GOT entry is
1118 // to be created, then we also emit ABS64 relocation for it.
1119 uint64_t GOTOffset = findOrAllocGOTEntry(Value, ELF::R_AARCH64_ABS64);
1120 resolveGOTOffsetRelocation(SectionID, Offset, GOTOffset + Addend,
1121 ELF::R_AARCH64_ADR_PREL_PG_HI21);
1123 } else if (RelType == ELF::R_AARCH64_LD64_GOT_LO12_NC) {
1124 uint64_t GOTOffset = findOrAllocGOTEntry(Value, ELF::R_AARCH64_ABS64);
1125 resolveGOTOffsetRelocation(SectionID, Offset, GOTOffset + Addend,
1126 ELF::R_AARCH64_LDST64_ABS_LO12_NC);
1128 processSimpleRelocation(SectionID, Offset, RelType, Value);
1130 } else if (Arch == Triple::arm) {
1131 if (RelType == ELF::R_ARM_PC24 || RelType == ELF::R_ARM_CALL ||
1132 RelType == ELF::R_ARM_JUMP24) {
1133 // This is an ARM branch relocation, need to use a stub function.
1134 DEBUG(dbgs() << "\t\tThis is an ARM branch relocation.\n");
1135 SectionEntry &Section = Sections[SectionID];
1137 // Look for an existing stub.
1138 StubMap::const_iterator i = Stubs.find(Value);
1139 if (i != Stubs.end()) {
1142 reinterpret_cast<uint64_t>(Section.getAddressWithOffset(i->second)),
1144 DEBUG(dbgs() << " Stub function found\n");
1146 // Create a new stub function.
1147 DEBUG(dbgs() << " Create a new stub function\n");
1148 Stubs[Value] = Section.getStubOffset();
1149 uint8_t *StubTargetAddr = createStubFunction(
1150 Section.getAddressWithOffset(Section.getStubOffset()));
1151 RelocationEntry RE(SectionID, StubTargetAddr - Section.getAddress(),
1152 ELF::R_ARM_ABS32, Value.Addend);
1153 if (Value.SymbolName)
1154 addRelocationForSymbol(RE, Value.SymbolName);
1156 addRelocationForSection(RE, Value.SectionID);
1158 resolveRelocation(Section, Offset, reinterpret_cast<uint64_t>(
1159 Section.getAddressWithOffset(
1160 Section.getStubOffset())),
1162 Section.advanceStubOffset(getMaxStubSize());
1165 uint32_t *Placeholder =
1166 reinterpret_cast<uint32_t*>(computePlaceholderAddress(SectionID, Offset));
1167 if (RelType == ELF::R_ARM_PREL31 || RelType == ELF::R_ARM_TARGET1 ||
1168 RelType == ELF::R_ARM_ABS32) {
1169 Value.Addend += *Placeholder;
1170 } else if (RelType == ELF::R_ARM_MOVW_ABS_NC || RelType == ELF::R_ARM_MOVT_ABS) {
1171 // See ELF for ARM documentation
1172 Value.Addend += (int16_t)((*Placeholder & 0xFFF) | (((*Placeholder >> 16) & 0xF) << 12));
1174 processSimpleRelocation(SectionID, Offset, RelType, Value);
1176 } else if (IsMipsO32ABI) {
1177 uint8_t *Placeholder = reinterpret_cast<uint8_t *>(
1178 computePlaceholderAddress(SectionID, Offset));
1179 uint32_t Opcode = readBytesUnaligned(Placeholder, 4);
1180 if (RelType == ELF::R_MIPS_26) {
1181 // This is an Mips branch relocation, need to use a stub function.
1182 DEBUG(dbgs() << "\t\tThis is a Mips branch relocation.");
1183 SectionEntry &Section = Sections[SectionID];
1185 // Extract the addend from the instruction.
1186 // We shift up by two since the Value will be down shifted again
1187 // when applying the relocation.
1188 uint32_t Addend = (Opcode & 0x03ffffff) << 2;
1190 Value.Addend += Addend;
1192 // Look up for existing stub.
1193 StubMap::const_iterator i = Stubs.find(Value);
1194 if (i != Stubs.end()) {
1195 RelocationEntry RE(SectionID, Offset, RelType, i->second);
1196 addRelocationForSection(RE, SectionID);
1197 DEBUG(dbgs() << " Stub function found\n");
1199 // Create a new stub function.
1200 DEBUG(dbgs() << " Create a new stub function\n");
1201 Stubs[Value] = Section.getStubOffset();
1203 unsigned AbiVariant;
1204 O.getPlatformFlags(AbiVariant);
1206 uint8_t *StubTargetAddr = createStubFunction(
1207 Section.getAddressWithOffset(Section.getStubOffset()), AbiVariant);
1209 // Creating Hi and Lo relocations for the filled stub instructions.
1210 RelocationEntry REHi(SectionID, StubTargetAddr - Section.getAddress(),
1211 ELF::R_MIPS_HI16, Value.Addend);
1212 RelocationEntry RELo(SectionID,
1213 StubTargetAddr - Section.getAddress() + 4,
1214 ELF::R_MIPS_LO16, Value.Addend);
1216 if (Value.SymbolName) {
1217 addRelocationForSymbol(REHi, Value.SymbolName);
1218 addRelocationForSymbol(RELo, Value.SymbolName);
1221 addRelocationForSection(REHi, Value.SectionID);
1222 addRelocationForSection(RELo, Value.SectionID);
1225 RelocationEntry RE(SectionID, Offset, RelType, Section.getStubOffset());
1226 addRelocationForSection(RE, SectionID);
1227 Section.advanceStubOffset(getMaxStubSize());
1229 } else if (RelType == ELF::R_MIPS_HI16 || RelType == ELF::R_MIPS_PCHI16) {
1230 int64_t Addend = (Opcode & 0x0000ffff) << 16;
1231 RelocationEntry RE(SectionID, Offset, RelType, Addend);
1232 PendingRelocs.push_back(std::make_pair(Value, RE));
1233 } else if (RelType == ELF::R_MIPS_LO16 || RelType == ELF::R_MIPS_PCLO16) {
1234 int64_t Addend = Value.Addend + SignExtend32<16>(Opcode & 0x0000ffff);
1235 for (auto I = PendingRelocs.begin(); I != PendingRelocs.end();) {
1236 const RelocationValueRef &MatchingValue = I->first;
1237 RelocationEntry &Reloc = I->second;
1238 if (MatchingValue == Value &&
1239 RelType == getMatchingLoRelocation(Reloc.RelType) &&
1240 SectionID == Reloc.SectionID) {
1241 Reloc.Addend += Addend;
1242 if (Value.SymbolName)
1243 addRelocationForSymbol(Reloc, Value.SymbolName);
1245 addRelocationForSection(Reloc, Value.SectionID);
1246 I = PendingRelocs.erase(I);
1250 RelocationEntry RE(SectionID, Offset, RelType, Addend);
1251 if (Value.SymbolName)
1252 addRelocationForSymbol(RE, Value.SymbolName);
1254 addRelocationForSection(RE, Value.SectionID);
1256 if (RelType == ELF::R_MIPS_32)
1257 Value.Addend += Opcode;
1258 else if (RelType == ELF::R_MIPS_PC16)
1259 Value.Addend += SignExtend32<18>((Opcode & 0x0000ffff) << 2);
1260 else if (RelType == ELF::R_MIPS_PC19_S2)
1261 Value.Addend += SignExtend32<21>((Opcode & 0x0007ffff) << 2);
1262 else if (RelType == ELF::R_MIPS_PC21_S2)
1263 Value.Addend += SignExtend32<23>((Opcode & 0x001fffff) << 2);
1264 else if (RelType == ELF::R_MIPS_PC26_S2)
1265 Value.Addend += SignExtend32<28>((Opcode & 0x03ffffff) << 2);
1266 processSimpleRelocation(SectionID, Offset, RelType, Value);
1268 } else if (IsMipsN32ABI || IsMipsN64ABI) {
1269 uint32_t r_type = RelType & 0xff;
1270 RelocationEntry RE(SectionID, Offset, RelType, Value.Addend);
1271 if (r_type == ELF::R_MIPS_CALL16 || r_type == ELF::R_MIPS_GOT_PAGE
1272 || r_type == ELF::R_MIPS_GOT_DISP) {
1273 StringMap<uint64_t>::iterator i = GOTSymbolOffsets.find(TargetName);
1274 if (i != GOTSymbolOffsets.end())
1275 RE.SymOffset = i->second;
1277 RE.SymOffset = allocateGOTEntries(1);
1278 GOTSymbolOffsets[TargetName] = RE.SymOffset;
1281 if (Value.SymbolName)
1282 addRelocationForSymbol(RE, Value.SymbolName);
1284 addRelocationForSection(RE, Value.SectionID);
1285 } else if (Arch == Triple::ppc64 || Arch == Triple::ppc64le) {
1286 if (RelType == ELF::R_PPC64_REL24) {
1287 // Determine ABI variant in use for this object.
1288 unsigned AbiVariant;
1289 Obj.getPlatformFlags(AbiVariant);
1290 AbiVariant &= ELF::EF_PPC64_ABI;
1291 // A PPC branch relocation will need a stub function if the target is
1292 // an external symbol (Symbol::ST_Unknown) or if the target address
1293 // is not within the signed 24-bits branch address.
1294 SectionEntry &Section = Sections[SectionID];
1295 uint8_t *Target = Section.getAddressWithOffset(Offset);
1296 bool RangeOverflow = false;
1297 if (SymType != SymbolRef::ST_Unknown) {
1298 if (AbiVariant != 2) {
1299 // In the ELFv1 ABI, a function call may point to the .opd entry,
1300 // so the final symbol value is calculated based on the relocation
1301 // values in the .opd section.
1302 if (auto Err = findOPDEntrySection(Obj, ObjSectionToID, Value))
1303 return std::move(Err);
1305 // In the ELFv2 ABI, a function symbol may provide a local entry
1306 // point, which must be used for direct calls.
1307 uint8_t SymOther = Symbol->getOther();
1308 Value.Addend += ELF::decodePPC64LocalEntryOffset(SymOther);
1310 uint8_t *RelocTarget =
1311 Sections[Value.SectionID].getAddressWithOffset(Value.Addend);
1312 int32_t delta = static_cast<int32_t>(Target - RelocTarget);
1313 // If it is within 26-bits branch range, just set the branch target
1314 if (SignExtend32<26>(delta) == delta) {
1315 RelocationEntry RE(SectionID, Offset, RelType, Value.Addend);
1316 if (Value.SymbolName)
1317 addRelocationForSymbol(RE, Value.SymbolName);
1319 addRelocationForSection(RE, Value.SectionID);
1321 RangeOverflow = true;
1324 if (SymType == SymbolRef::ST_Unknown || RangeOverflow) {
1325 // It is an external symbol (SymbolRef::ST_Unknown) or within a range
1326 // larger than 24-bits.
1327 StubMap::const_iterator i = Stubs.find(Value);
1328 if (i != Stubs.end()) {
1329 // Symbol function stub already created, just relocate to it
1330 resolveRelocation(Section, Offset,
1331 reinterpret_cast<uint64_t>(
1332 Section.getAddressWithOffset(i->second)),
1334 DEBUG(dbgs() << " Stub function found\n");
1336 // Create a new stub function.
1337 DEBUG(dbgs() << " Create a new stub function\n");
1338 Stubs[Value] = Section.getStubOffset();
1339 uint8_t *StubTargetAddr = createStubFunction(
1340 Section.getAddressWithOffset(Section.getStubOffset()),
1342 RelocationEntry RE(SectionID, StubTargetAddr - Section.getAddress(),
1343 ELF::R_PPC64_ADDR64, Value.Addend);
1345 // Generates the 64-bits address loads as exemplified in section
1346 // 4.5.1 in PPC64 ELF ABI. Note that the relocations need to
1347 // apply to the low part of the instructions, so we have to update
1348 // the offset according to the target endianness.
1349 uint64_t StubRelocOffset = StubTargetAddr - Section.getAddress();
1350 if (!IsTargetLittleEndian)
1351 StubRelocOffset += 2;
1353 RelocationEntry REhst(SectionID, StubRelocOffset + 0,
1354 ELF::R_PPC64_ADDR16_HIGHEST, Value.Addend);
1355 RelocationEntry REhr(SectionID, StubRelocOffset + 4,
1356 ELF::R_PPC64_ADDR16_HIGHER, Value.Addend);
1357 RelocationEntry REh(SectionID, StubRelocOffset + 12,
1358 ELF::R_PPC64_ADDR16_HI, Value.Addend);
1359 RelocationEntry REl(SectionID, StubRelocOffset + 16,
1360 ELF::R_PPC64_ADDR16_LO, Value.Addend);
1362 if (Value.SymbolName) {
1363 addRelocationForSymbol(REhst, Value.SymbolName);
1364 addRelocationForSymbol(REhr, Value.SymbolName);
1365 addRelocationForSymbol(REh, Value.SymbolName);
1366 addRelocationForSymbol(REl, Value.SymbolName);
1368 addRelocationForSection(REhst, Value.SectionID);
1369 addRelocationForSection(REhr, Value.SectionID);
1370 addRelocationForSection(REh, Value.SectionID);
1371 addRelocationForSection(REl, Value.SectionID);
1374 resolveRelocation(Section, Offset, reinterpret_cast<uint64_t>(
1375 Section.getAddressWithOffset(
1376 Section.getStubOffset())),
1378 Section.advanceStubOffset(getMaxStubSize());
1380 if (SymType == SymbolRef::ST_Unknown) {
1381 // Restore the TOC for external calls
1382 if (AbiVariant == 2)
1383 writeInt32BE(Target + 4, 0xE8410018); // ld r2,28(r1)
1385 writeInt32BE(Target + 4, 0xE8410028); // ld r2,40(r1)
1388 } else if (RelType == ELF::R_PPC64_TOC16 ||
1389 RelType == ELF::R_PPC64_TOC16_DS ||
1390 RelType == ELF::R_PPC64_TOC16_LO ||
1391 RelType == ELF::R_PPC64_TOC16_LO_DS ||
1392 RelType == ELF::R_PPC64_TOC16_HI ||
1393 RelType == ELF::R_PPC64_TOC16_HA) {
1394 // These relocations are supposed to subtract the TOC address from
1395 // the final value. This does not fit cleanly into the RuntimeDyld
1396 // scheme, since there may be *two* sections involved in determining
1397 // the relocation value (the section of the symbol referred to by the
1398 // relocation, and the TOC section associated with the current module).
1400 // Fortunately, these relocations are currently only ever generated
1401 // referring to symbols that themselves reside in the TOC, which means
1402 // that the two sections are actually the same. Thus they cancel out
1403 // and we can immediately resolve the relocation right now.
1405 case ELF::R_PPC64_TOC16: RelType = ELF::R_PPC64_ADDR16; break;
1406 case ELF::R_PPC64_TOC16_DS: RelType = ELF::R_PPC64_ADDR16_DS; break;
1407 case ELF::R_PPC64_TOC16_LO: RelType = ELF::R_PPC64_ADDR16_LO; break;
1408 case ELF::R_PPC64_TOC16_LO_DS: RelType = ELF::R_PPC64_ADDR16_LO_DS; break;
1409 case ELF::R_PPC64_TOC16_HI: RelType = ELF::R_PPC64_ADDR16_HI; break;
1410 case ELF::R_PPC64_TOC16_HA: RelType = ELF::R_PPC64_ADDR16_HA; break;
1411 default: llvm_unreachable("Wrong relocation type.");
1414 RelocationValueRef TOCValue;
1415 if (auto Err = findPPC64TOCSection(Obj, ObjSectionToID, TOCValue))
1416 return std::move(Err);
1417 if (Value.SymbolName || Value.SectionID != TOCValue.SectionID)
1418 llvm_unreachable("Unsupported TOC relocation.");
1419 Value.Addend -= TOCValue.Addend;
1420 resolveRelocation(Sections[SectionID], Offset, Value.Addend, RelType, 0);
1422 // There are two ways to refer to the TOC address directly: either
1423 // via a ELF::R_PPC64_TOC relocation (where both symbol and addend are
1424 // ignored), or via any relocation that refers to the magic ".TOC."
1425 // symbols (in which case the addend is respected).
1426 if (RelType == ELF::R_PPC64_TOC) {
1427 RelType = ELF::R_PPC64_ADDR64;
1428 if (auto Err = findPPC64TOCSection(Obj, ObjSectionToID, Value))
1429 return std::move(Err);
1430 } else if (TargetName == ".TOC.") {
1431 if (auto Err = findPPC64TOCSection(Obj, ObjSectionToID, Value))
1432 return std::move(Err);
1433 Value.Addend += Addend;
1436 RelocationEntry RE(SectionID, Offset, RelType, Value.Addend);
1438 if (Value.SymbolName)
1439 addRelocationForSymbol(RE, Value.SymbolName);
1441 addRelocationForSection(RE, Value.SectionID);
1443 } else if (Arch == Triple::systemz &&
1444 (RelType == ELF::R_390_PLT32DBL || RelType == ELF::R_390_GOTENT)) {
1445 // Create function stubs for both PLT and GOT references, regardless of
1446 // whether the GOT reference is to data or code. The stub contains the
1447 // full address of the symbol, as needed by GOT references, and the
1448 // executable part only adds an overhead of 8 bytes.
1450 // We could try to conserve space by allocating the code and data
1451 // parts of the stub separately. However, as things stand, we allocate
1452 // a stub for every relocation, so using a GOT in JIT code should be
1453 // no less space efficient than using an explicit constant pool.
1454 DEBUG(dbgs() << "\t\tThis is a SystemZ indirect relocation.");
1455 SectionEntry &Section = Sections[SectionID];
1457 // Look for an existing stub.
1458 StubMap::const_iterator i = Stubs.find(Value);
1459 uintptr_t StubAddress;
1460 if (i != Stubs.end()) {
1461 StubAddress = uintptr_t(Section.getAddressWithOffset(i->second));
1462 DEBUG(dbgs() << " Stub function found\n");
1464 // Create a new stub function.
1465 DEBUG(dbgs() << " Create a new stub function\n");
1467 uintptr_t BaseAddress = uintptr_t(Section.getAddress());
1468 uintptr_t StubAlignment = getStubAlignment();
1470 (BaseAddress + Section.getStubOffset() + StubAlignment - 1) &
1472 unsigned StubOffset = StubAddress - BaseAddress;
1474 Stubs[Value] = StubOffset;
1475 createStubFunction((uint8_t *)StubAddress);
1476 RelocationEntry RE(SectionID, StubOffset + 8, ELF::R_390_64,
1478 if (Value.SymbolName)
1479 addRelocationForSymbol(RE, Value.SymbolName);
1481 addRelocationForSection(RE, Value.SectionID);
1482 Section.advanceStubOffset(getMaxStubSize());
1485 if (RelType == ELF::R_390_GOTENT)
1486 resolveRelocation(Section, Offset, StubAddress + 8, ELF::R_390_PC32DBL,
1489 resolveRelocation(Section, Offset, StubAddress, RelType, Addend);
1490 } else if (Arch == Triple::x86_64) {
1491 if (RelType == ELF::R_X86_64_PLT32) {
1492 // The way the PLT relocations normally work is that the linker allocates
1494 // PLT and this relocation makes a PC-relative call into the PLT. The PLT
1495 // entry will then jump to an address provided by the GOT. On first call,
1497 // GOT address will point back into PLT code that resolves the symbol. After
1498 // the first call, the GOT entry points to the actual function.
1500 // For local functions we're ignoring all of that here and just replacing
1501 // the PLT32 relocation type with PC32, which will translate the relocation
1502 // into a PC-relative call directly to the function. For external symbols we
1503 // can't be sure the function will be within 2^32 bytes of the call site, so
1504 // we need to create a stub, which calls into the GOT. This case is
1505 // equivalent to the usual PLT implementation except that we use the stub
1506 // mechanism in RuntimeDyld (which puts stubs at the end of the section)
1507 // rather than allocating a PLT section.
1508 if (Value.SymbolName) {
1509 // This is a call to an external function.
1510 // Look for an existing stub.
1511 SectionEntry &Section = Sections[SectionID];
1512 StubMap::const_iterator i = Stubs.find(Value);
1513 uintptr_t StubAddress;
1514 if (i != Stubs.end()) {
1515 StubAddress = uintptr_t(Section.getAddress()) + i->second;
1516 DEBUG(dbgs() << " Stub function found\n");
1518 // Create a new stub function (equivalent to a PLT entry).
1519 DEBUG(dbgs() << " Create a new stub function\n");
1521 uintptr_t BaseAddress = uintptr_t(Section.getAddress());
1522 uintptr_t StubAlignment = getStubAlignment();
1524 (BaseAddress + Section.getStubOffset() + StubAlignment - 1) &
1526 unsigned StubOffset = StubAddress - BaseAddress;
1527 Stubs[Value] = StubOffset;
1528 createStubFunction((uint8_t *)StubAddress);
1530 // Bump our stub offset counter
1531 Section.advanceStubOffset(getMaxStubSize());
1533 // Allocate a GOT Entry
1534 uint64_t GOTOffset = allocateGOTEntries(1);
1536 // The load of the GOT address has an addend of -4
1537 resolveGOTOffsetRelocation(SectionID, StubOffset + 2, GOTOffset - 4,
1538 ELF::R_X86_64_PC32);
1540 // Fill in the value of the symbol we're targeting into the GOT
1541 addRelocationForSymbol(
1542 computeGOTOffsetRE(GOTOffset, 0, ELF::R_X86_64_64),
1546 // Make the target call a call into the stub table.
1547 resolveRelocation(Section, Offset, StubAddress, ELF::R_X86_64_PC32,
1550 RelocationEntry RE(SectionID, Offset, ELF::R_X86_64_PC32, Value.Addend,
1552 addRelocationForSection(RE, Value.SectionID);
1554 } else if (RelType == ELF::R_X86_64_GOTPCREL ||
1555 RelType == ELF::R_X86_64_GOTPCRELX ||
1556 RelType == ELF::R_X86_64_REX_GOTPCRELX) {
1557 uint64_t GOTOffset = allocateGOTEntries(1);
1558 resolveGOTOffsetRelocation(SectionID, Offset, GOTOffset + Addend,
1559 ELF::R_X86_64_PC32);
1561 // Fill in the value of the symbol we're targeting into the GOT
1562 RelocationEntry RE =
1563 computeGOTOffsetRE(GOTOffset, Value.Offset, ELF::R_X86_64_64);
1564 if (Value.SymbolName)
1565 addRelocationForSymbol(RE, Value.SymbolName);
1567 addRelocationForSection(RE, Value.SectionID);
1568 } else if (RelType == ELF::R_X86_64_PC32) {
1569 Value.Addend += support::ulittle32_t::ref(computePlaceholderAddress(SectionID, Offset));
1570 processSimpleRelocation(SectionID, Offset, RelType, Value);
1571 } else if (RelType == ELF::R_X86_64_PC64) {
1572 Value.Addend += support::ulittle64_t::ref(computePlaceholderAddress(SectionID, Offset));
1573 processSimpleRelocation(SectionID, Offset, RelType, Value);
1575 processSimpleRelocation(SectionID, Offset, RelType, Value);
1578 if (Arch == Triple::x86) {
1579 Value.Addend += support::ulittle32_t::ref(computePlaceholderAddress(SectionID, Offset));
1581 processSimpleRelocation(SectionID, Offset, RelType, Value);
1586 size_t RuntimeDyldELF::getGOTEntrySize() {
1587 // We don't use the GOT in all of these cases, but it's essentially free
1588 // to put them all here.
1591 case Triple::x86_64:
1592 case Triple::aarch64:
1593 case Triple::aarch64_be:
1595 case Triple::ppc64le:
1596 case Triple::systemz:
1597 Result = sizeof(uint64_t);
1602 Result = sizeof(uint32_t);
1605 case Triple::mipsel:
1606 case Triple::mips64:
1607 case Triple::mips64el:
1608 if (IsMipsO32ABI || IsMipsN32ABI)
1609 Result = sizeof(uint32_t);
1610 else if (IsMipsN64ABI)
1611 Result = sizeof(uint64_t);
1613 llvm_unreachable("Mips ABI not handled");
1616 llvm_unreachable("Unsupported CPU type!");
1621 uint64_t RuntimeDyldELF::allocateGOTEntries(unsigned no) {
1622 if (GOTSectionID == 0) {
1623 GOTSectionID = Sections.size();
1624 // Reserve a section id. We'll allocate the section later
1625 // once we know the total size
1626 Sections.push_back(SectionEntry(".got", nullptr, 0, 0, 0));
1628 uint64_t StartOffset = CurrentGOTIndex * getGOTEntrySize();
1629 CurrentGOTIndex += no;
1633 uint64_t RuntimeDyldELF::findOrAllocGOTEntry(const RelocationValueRef &Value,
1634 unsigned GOTRelType) {
1635 auto E = GOTOffsetMap.insert({Value, 0});
1637 uint64_t GOTOffset = allocateGOTEntries(1);
1639 // Create relocation for newly created GOT entry
1640 RelocationEntry RE =
1641 computeGOTOffsetRE(GOTOffset, Value.Offset, GOTRelType);
1642 if (Value.SymbolName)
1643 addRelocationForSymbol(RE, Value.SymbolName);
1645 addRelocationForSection(RE, Value.SectionID);
1647 E.first->second = GOTOffset;
1650 return E.first->second;
1653 void RuntimeDyldELF::resolveGOTOffsetRelocation(unsigned SectionID,
1657 // Fill in the relative address of the GOT Entry into the stub
1658 RelocationEntry GOTRE(SectionID, Offset, Type, GOTOffset);
1659 addRelocationForSection(GOTRE, GOTSectionID);
1662 RelocationEntry RuntimeDyldELF::computeGOTOffsetRE(uint64_t GOTOffset,
1663 uint64_t SymbolOffset,
1665 return RelocationEntry(GOTSectionID, GOTOffset, Type, SymbolOffset);
1668 Error RuntimeDyldELF::finalizeLoad(const ObjectFile &Obj,
1669 ObjSectionToIDMap &SectionMap) {
1671 if (!PendingRelocs.empty())
1672 return make_error<RuntimeDyldError>("Can't find matching LO16 reloc");
1674 // If necessary, allocate the global offset table
1675 if (GOTSectionID != 0) {
1676 // Allocate memory for the section
1677 size_t TotalSize = CurrentGOTIndex * getGOTEntrySize();
1678 uint8_t *Addr = MemMgr.allocateDataSection(TotalSize, getGOTEntrySize(),
1679 GOTSectionID, ".got", false);
1681 return make_error<RuntimeDyldError>("Unable to allocate memory for GOT!");
1683 Sections[GOTSectionID] =
1684 SectionEntry(".got", Addr, TotalSize, TotalSize, 0);
1687 Checker->registerSection(Obj.getFileName(), GOTSectionID);
1689 // For now, initialize all GOT entries to zero. We'll fill them in as
1690 // needed when GOT-based relocations are applied.
1691 memset(Addr, 0, TotalSize);
1692 if (IsMipsN32ABI || IsMipsN64ABI) {
1693 // To correctly resolve Mips GOT relocations, we need a mapping from
1694 // object's sections to GOTs.
1695 for (section_iterator SI = Obj.section_begin(), SE = Obj.section_end();
1697 if (SI->relocation_begin() != SI->relocation_end()) {
1698 section_iterator RelocatedSection = SI->getRelocatedSection();
1699 ObjSectionToIDMap::iterator i = SectionMap.find(*RelocatedSection);
1700 assert (i != SectionMap.end());
1701 SectionToGOTMap[i->second] = GOTSectionID;
1704 GOTSymbolOffsets.clear();
1708 // Look for and record the EH frame section.
1709 ObjSectionToIDMap::iterator i, e;
1710 for (i = SectionMap.begin(), e = SectionMap.end(); i != e; ++i) {
1711 const SectionRef &Section = i->first;
1713 Section.getName(Name);
1714 if (Name == ".eh_frame") {
1715 UnregisteredEHFrameSections.push_back(i->second);
1721 CurrentGOTIndex = 0;
1723 return Error::success();
1726 bool RuntimeDyldELF::isCompatibleFile(const object::ObjectFile &Obj) const {
1730 bool RuntimeDyldELF::relocationNeedsGot(const RelocationRef &R) const {
1731 unsigned RelTy = R.getType();
1732 if (Arch == Triple::aarch64 || Arch == Triple::aarch64_be)
1733 return RelTy == ELF::R_AARCH64_ADR_GOT_PAGE ||
1734 RelTy == ELF::R_AARCH64_LD64_GOT_LO12_NC;
1736 if (Arch == Triple::x86_64)
1737 return RelTy == ELF::R_X86_64_GOTPCREL ||
1738 RelTy == ELF::R_X86_64_GOTPCRELX ||
1739 RelTy == ELF::R_X86_64_REX_GOTPCRELX;
1743 bool RuntimeDyldELF::relocationNeedsStub(const RelocationRef &R) const {
1744 if (Arch != Triple::x86_64)
1745 return true; // Conservative answer
1747 switch (R.getType()) {
1749 return true; // Conservative answer
1752 case ELF::R_X86_64_GOTPCREL:
1753 case ELF::R_X86_64_GOTPCRELX:
1754 case ELF::R_X86_64_REX_GOTPCRELX:
1755 case ELF::R_X86_64_PC32:
1756 case ELF::R_X86_64_PC64:
1757 case ELF::R_X86_64_64:
1758 // We know that these reloation types won't need a stub function. This list
1759 // can be extended as needed.