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 "llvm/ADT/IntervalMap.h"
17 #include "llvm/ADT/STLExtras.h"
18 #include "llvm/ADT/StringRef.h"
19 #include "llvm/ADT/Triple.h"
20 #include "llvm/MC/MCStreamer.h"
21 #include "llvm/Object/ELFObjectFile.h"
22 #include "llvm/Object/ObjectFile.h"
23 #include "llvm/Support/ELF.h"
24 #include "llvm/Support/Endian.h"
25 #include "llvm/Support/MemoryBuffer.h"
26 #include "llvm/Support/TargetRegistry.h"
29 using namespace llvm::object;
31 #define DEBUG_TYPE "dyld"
33 static inline std::error_code check(std::error_code Err) {
35 report_fatal_error(Err.message());
42 template <class ELFT> class DyldELFObject : public ELFObjectFile<ELFT> {
43 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT)
45 typedef Elf_Shdr_Impl<ELFT> Elf_Shdr;
46 typedef Elf_Sym_Impl<ELFT> Elf_Sym;
47 typedef Elf_Rel_Impl<ELFT, false> Elf_Rel;
48 typedef Elf_Rel_Impl<ELFT, true> Elf_Rela;
50 typedef Elf_Ehdr_Impl<ELFT> Elf_Ehdr;
52 typedef typename ELFDataTypeTypedefHelper<ELFT>::value_type addr_type;
55 DyldELFObject(MemoryBufferRef Wrapper, std::error_code &ec);
57 void updateSectionAddress(const SectionRef &Sec, uint64_t Addr);
59 void updateSymbolAddress(const SymbolRef &SymRef, uint64_t Addr);
61 // Methods for type inquiry through isa, cast and dyn_cast
62 static inline bool classof(const Binary *v) {
63 return (isa<ELFObjectFile<ELFT>>(v) &&
64 classof(cast<ELFObjectFile<ELFT>>(v)));
66 static inline bool classof(const ELFObjectFile<ELFT> *v) {
67 return v->isDyldType();
73 // The MemoryBuffer passed into this constructor is just a wrapper around the
74 // actual memory. Ultimately, the Binary parent class will take ownership of
75 // this MemoryBuffer object but not the underlying memory.
77 DyldELFObject<ELFT>::DyldELFObject(MemoryBufferRef Wrapper, std::error_code &EC)
78 : ELFObjectFile<ELFT>(Wrapper, EC) {
79 this->isDyldELFObject = true;
83 void DyldELFObject<ELFT>::updateSectionAddress(const SectionRef &Sec,
85 DataRefImpl ShdrRef = Sec.getRawDataRefImpl();
87 const_cast<Elf_Shdr *>(reinterpret_cast<const Elf_Shdr *>(ShdrRef.p));
89 // This assumes the address passed in matches the target address bitness
90 // The template-based type cast handles everything else.
91 shdr->sh_addr = static_cast<addr_type>(Addr);
95 void DyldELFObject<ELFT>::updateSymbolAddress(const SymbolRef &SymRef,
98 Elf_Sym *sym = const_cast<Elf_Sym *>(
99 ELFObjectFile<ELFT>::getSymbol(SymRef.getRawDataRefImpl()));
101 // This assumes the address passed in matches the target address bitness
102 // The template-based type cast handles everything else.
103 sym->st_value = static_cast<addr_type>(Addr);
106 class LoadedELFObjectInfo final
107 : public RuntimeDyld::LoadedObjectInfoHelper<LoadedELFObjectInfo> {
109 LoadedELFObjectInfo(RuntimeDyldImpl &RTDyld, ObjSectionToIDMap ObjSecToIDMap)
110 : LoadedObjectInfoHelper(RTDyld, std::move(ObjSecToIDMap)) {}
112 OwningBinary<ObjectFile>
113 getObjectForDebug(const ObjectFile &Obj) const override;
116 template <typename ELFT>
117 std::unique_ptr<DyldELFObject<ELFT>>
118 createRTDyldELFObject(MemoryBufferRef Buffer,
119 const ObjectFile &SourceObject,
120 const LoadedELFObjectInfo &L,
121 std::error_code &ec) {
122 typedef typename ELFFile<ELFT>::Elf_Shdr Elf_Shdr;
123 typedef typename ELFDataTypeTypedefHelper<ELFT>::value_type addr_type;
125 std::unique_ptr<DyldELFObject<ELFT>> Obj =
126 llvm::make_unique<DyldELFObject<ELFT>>(Buffer, ec);
128 // Iterate over all sections in the object.
129 auto SI = SourceObject.section_begin();
130 for (const auto &Sec : Obj->sections()) {
131 StringRef SectionName;
132 Sec.getName(SectionName);
133 if (SectionName != "") {
134 DataRefImpl ShdrRef = Sec.getRawDataRefImpl();
135 Elf_Shdr *shdr = const_cast<Elf_Shdr *>(
136 reinterpret_cast<const Elf_Shdr *>(ShdrRef.p));
138 if (uint64_t SecLoadAddr = L.getSectionLoadAddress(*SI)) {
139 // This assumes that the address passed in matches the target address
140 // bitness. The template-based type cast handles everything else.
141 shdr->sh_addr = static_cast<addr_type>(SecLoadAddr);
150 OwningBinary<ObjectFile> createELFDebugObject(const ObjectFile &Obj,
151 const LoadedELFObjectInfo &L) {
152 assert(Obj.isELF() && "Not an ELF object file.");
154 std::unique_ptr<MemoryBuffer> Buffer =
155 MemoryBuffer::getMemBufferCopy(Obj.getData(), Obj.getFileName());
159 std::unique_ptr<ObjectFile> DebugObj;
160 if (Obj.getBytesInAddress() == 4 && Obj.isLittleEndian()) {
161 typedef ELFType<support::little, false> ELF32LE;
162 DebugObj = createRTDyldELFObject<ELF32LE>(Buffer->getMemBufferRef(), Obj, L,
164 } else if (Obj.getBytesInAddress() == 4 && !Obj.isLittleEndian()) {
165 typedef ELFType<support::big, false> ELF32BE;
166 DebugObj = createRTDyldELFObject<ELF32BE>(Buffer->getMemBufferRef(), Obj, L,
168 } else if (Obj.getBytesInAddress() == 8 && !Obj.isLittleEndian()) {
169 typedef ELFType<support::big, true> ELF64BE;
170 DebugObj = createRTDyldELFObject<ELF64BE>(Buffer->getMemBufferRef(), Obj, L,
172 } else if (Obj.getBytesInAddress() == 8 && Obj.isLittleEndian()) {
173 typedef ELFType<support::little, true> ELF64LE;
174 DebugObj = createRTDyldELFObject<ELF64LE>(Buffer->getMemBufferRef(), Obj, L,
177 llvm_unreachable("Unexpected ELF format");
179 assert(!ec && "Could not construct copy ELF object file");
181 return OwningBinary<ObjectFile>(std::move(DebugObj), std::move(Buffer));
184 OwningBinary<ObjectFile>
185 LoadedELFObjectInfo::getObjectForDebug(const ObjectFile &Obj) const {
186 return createELFDebugObject(Obj, *this);
189 } // anonymous namespace
193 RuntimeDyldELF::RuntimeDyldELF(RuntimeDyld::MemoryManager &MemMgr,
194 RuntimeDyld::SymbolResolver &Resolver)
195 : RuntimeDyldImpl(MemMgr, Resolver), GOTSectionID(0), CurrentGOTIndex(0) {}
196 RuntimeDyldELF::~RuntimeDyldELF() {}
198 void RuntimeDyldELF::registerEHFrames() {
199 for (int i = 0, e = UnregisteredEHFrameSections.size(); i != e; ++i) {
200 SID EHFrameSID = UnregisteredEHFrameSections[i];
201 uint8_t *EHFrameAddr = Sections[EHFrameSID].getAddress();
202 uint64_t EHFrameLoadAddr = Sections[EHFrameSID].getLoadAddress();
203 size_t EHFrameSize = Sections[EHFrameSID].getSize();
204 MemMgr.registerEHFrames(EHFrameAddr, EHFrameLoadAddr, EHFrameSize);
205 RegisteredEHFrameSections.push_back(EHFrameSID);
207 UnregisteredEHFrameSections.clear();
210 void RuntimeDyldELF::deregisterEHFrames() {
211 for (int i = 0, e = RegisteredEHFrameSections.size(); i != e; ++i) {
212 SID EHFrameSID = RegisteredEHFrameSections[i];
213 uint8_t *EHFrameAddr = Sections[EHFrameSID].getAddress();
214 uint64_t EHFrameLoadAddr = Sections[EHFrameSID].getLoadAddress();
215 size_t EHFrameSize = Sections[EHFrameSID].getSize();
216 MemMgr.deregisterEHFrames(EHFrameAddr, EHFrameLoadAddr, EHFrameSize);
218 RegisteredEHFrameSections.clear();
221 std::unique_ptr<RuntimeDyld::LoadedObjectInfo>
222 RuntimeDyldELF::loadObject(const object::ObjectFile &O) {
223 return llvm::make_unique<LoadedELFObjectInfo>(*this, loadObjectImpl(O));
226 void RuntimeDyldELF::resolveX86_64Relocation(const SectionEntry &Section,
227 uint64_t Offset, uint64_t Value,
228 uint32_t Type, int64_t Addend,
229 uint64_t SymOffset) {
232 llvm_unreachable("Relocation type not implemented yet!");
234 case ELF::R_X86_64_64: {
235 support::ulittle64_t::ref(Section.getAddressWithOffset(Offset)) =
237 DEBUG(dbgs() << "Writing " << format("%p", (Value + Addend)) << " at "
238 << format("%p\n", Section.getAddressWithOffset(Offset)));
241 case ELF::R_X86_64_32:
242 case ELF::R_X86_64_32S: {
244 assert((Type == ELF::R_X86_64_32 && (Value <= UINT32_MAX)) ||
245 (Type == ELF::R_X86_64_32S &&
246 ((int64_t)Value <= INT32_MAX && (int64_t)Value >= INT32_MIN)));
247 uint32_t TruncatedAddr = (Value & 0xFFFFFFFF);
248 support::ulittle32_t::ref(Section.getAddressWithOffset(Offset)) =
250 DEBUG(dbgs() << "Writing " << format("%p", TruncatedAddr) << " at "
251 << format("%p\n", Section.getAddressWithOffset(Offset)));
254 case ELF::R_X86_64_PC8: {
255 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
256 int64_t RealOffset = Value + Addend - FinalAddress;
257 assert(isInt<8>(RealOffset));
258 int8_t TruncOffset = (RealOffset & 0xFF);
259 Section.getAddress()[Offset] = TruncOffset;
262 case ELF::R_X86_64_PC32: {
263 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
264 int64_t RealOffset = Value + Addend - FinalAddress;
265 assert(isInt<32>(RealOffset));
266 int32_t TruncOffset = (RealOffset & 0xFFFFFFFF);
267 support::ulittle32_t::ref(Section.getAddressWithOffset(Offset)) =
271 case ELF::R_X86_64_PC64: {
272 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
273 int64_t RealOffset = Value + Addend - FinalAddress;
274 support::ulittle64_t::ref(Section.getAddressWithOffset(Offset)) =
281 void RuntimeDyldELF::resolveX86Relocation(const SectionEntry &Section,
282 uint64_t Offset, uint32_t Value,
283 uint32_t Type, int32_t Addend) {
285 case ELF::R_386_32: {
286 support::ulittle32_t::ref(Section.getAddressWithOffset(Offset)) =
290 case ELF::R_386_PC32: {
291 uint32_t FinalAddress =
292 Section.getLoadAddressWithOffset(Offset) & 0xFFFFFFFF;
293 uint32_t RealOffset = Value + Addend - FinalAddress;
294 support::ulittle32_t::ref(Section.getAddressWithOffset(Offset)) =
299 // There are other relocation types, but it appears these are the
300 // only ones currently used by the LLVM ELF object writer
301 llvm_unreachable("Relocation type not implemented yet!");
306 void RuntimeDyldELF::resolveAArch64Relocation(const SectionEntry &Section,
307 uint64_t Offset, uint64_t Value,
308 uint32_t Type, int64_t Addend) {
309 uint32_t *TargetPtr =
310 reinterpret_cast<uint32_t *>(Section.getAddressWithOffset(Offset));
311 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
313 DEBUG(dbgs() << "resolveAArch64Relocation, LocalAddress: 0x"
314 << format("%llx", Section.getAddressWithOffset(Offset))
315 << " FinalAddress: 0x" << format("%llx", FinalAddress)
316 << " Value: 0x" << format("%llx", Value) << " Type: 0x"
317 << format("%x", Type) << " Addend: 0x" << format("%llx", Addend)
322 llvm_unreachable("Relocation type not implemented yet!");
324 case ELF::R_AARCH64_ABS64: {
325 uint64_t *TargetPtr =
326 reinterpret_cast<uint64_t *>(Section.getAddressWithOffset(Offset));
327 *TargetPtr = Value + Addend;
330 case ELF::R_AARCH64_PREL32: {
331 uint64_t Result = Value + Addend - FinalAddress;
332 assert(static_cast<int64_t>(Result) >= INT32_MIN &&
333 static_cast<int64_t>(Result) <= UINT32_MAX);
334 *TargetPtr = static_cast<uint32_t>(Result & 0xffffffffU);
337 case ELF::R_AARCH64_CALL26: // fallthrough
338 case ELF::R_AARCH64_JUMP26: {
339 // Operation: S+A-P. Set Call or B immediate value to bits fff_fffc of the
341 uint64_t BranchImm = Value + Addend - FinalAddress;
343 // "Check that -2^27 <= result < 2^27".
344 assert(isInt<28>(BranchImm));
346 // AArch64 code is emitted with .rela relocations. The data already in any
347 // bits affected by the relocation on entry is garbage.
348 *TargetPtr &= 0xfc000000U;
349 // Immediate goes in bits 25:0 of B and BL.
350 *TargetPtr |= static_cast<uint32_t>(BranchImm & 0xffffffcU) >> 2;
353 case ELF::R_AARCH64_MOVW_UABS_G3: {
354 uint64_t Result = Value + Addend;
356 // AArch64 code is emitted with .rela relocations. The data already in any
357 // bits affected by the relocation on entry is garbage.
358 *TargetPtr &= 0xffe0001fU;
359 // Immediate goes in bits 20:5 of MOVZ/MOVK instruction
360 *TargetPtr |= Result >> (48 - 5);
361 // Shift must be "lsl #48", in bits 22:21
362 assert((*TargetPtr >> 21 & 0x3) == 3 && "invalid shift for relocation");
365 case ELF::R_AARCH64_MOVW_UABS_G2_NC: {
366 uint64_t Result = Value + Addend;
368 // AArch64 code is emitted with .rela relocations. The data already in any
369 // bits affected by the relocation on entry is garbage.
370 *TargetPtr &= 0xffe0001fU;
371 // Immediate goes in bits 20:5 of MOVZ/MOVK instruction
372 *TargetPtr |= ((Result & 0xffff00000000ULL) >> (32 - 5));
373 // Shift must be "lsl #32", in bits 22:21
374 assert((*TargetPtr >> 21 & 0x3) == 2 && "invalid shift for relocation");
377 case ELF::R_AARCH64_MOVW_UABS_G1_NC: {
378 uint64_t Result = Value + Addend;
380 // AArch64 code is emitted with .rela relocations. The data already in any
381 // bits affected by the relocation on entry is garbage.
382 *TargetPtr &= 0xffe0001fU;
383 // Immediate goes in bits 20:5 of MOVZ/MOVK instruction
384 *TargetPtr |= ((Result & 0xffff0000U) >> (16 - 5));
385 // Shift must be "lsl #16", in bits 22:2
386 assert((*TargetPtr >> 21 & 0x3) == 1 && "invalid shift for relocation");
389 case ELF::R_AARCH64_MOVW_UABS_G0_NC: {
390 uint64_t Result = Value + Addend;
392 // AArch64 code is emitted with .rela relocations. The data already in any
393 // bits affected by the relocation on entry is garbage.
394 *TargetPtr &= 0xffe0001fU;
395 // Immediate goes in bits 20:5 of MOVZ/MOVK instruction
396 *TargetPtr |= ((Result & 0xffffU) << 5);
397 // Shift must be "lsl #0", in bits 22:21.
398 assert((*TargetPtr >> 21 & 0x3) == 0 && "invalid shift for relocation");
401 case ELF::R_AARCH64_ADR_PREL_PG_HI21: {
402 // Operation: Page(S+A) - Page(P)
404 ((Value + Addend) & ~0xfffULL) - (FinalAddress & ~0xfffULL);
406 // Check that -2^32 <= X < 2^32
407 assert(isInt<33>(Result) && "overflow check failed for relocation");
409 // AArch64 code is emitted with .rela relocations. The data already in any
410 // bits affected by the relocation on entry is garbage.
411 *TargetPtr &= 0x9f00001fU;
412 // Immediate goes in bits 30:29 + 5:23 of ADRP instruction, taken
413 // from bits 32:12 of X.
414 *TargetPtr |= ((Result & 0x3000U) << (29 - 12));
415 *TargetPtr |= ((Result & 0x1ffffc000ULL) >> (14 - 5));
418 case ELF::R_AARCH64_LDST32_ABS_LO12_NC: {
420 uint64_t Result = Value + Addend;
422 // AArch64 code is emitted with .rela relocations. The data already in any
423 // bits affected by the relocation on entry is garbage.
424 *TargetPtr &= 0xffc003ffU;
425 // Immediate goes in bits 21:10 of LD/ST instruction, taken
426 // from bits 11:2 of X
427 *TargetPtr |= ((Result & 0xffc) << (10 - 2));
430 case ELF::R_AARCH64_LDST64_ABS_LO12_NC: {
432 uint64_t Result = Value + Addend;
434 // AArch64 code is emitted with .rela relocations. The data already in any
435 // bits affected by the relocation on entry is garbage.
436 *TargetPtr &= 0xffc003ffU;
437 // Immediate goes in bits 21:10 of LD/ST instruction, taken
438 // from bits 11:3 of X
439 *TargetPtr |= ((Result & 0xff8) << (10 - 3));
445 void RuntimeDyldELF::resolveARMRelocation(const SectionEntry &Section,
446 uint64_t Offset, uint32_t Value,
447 uint32_t Type, int32_t Addend) {
448 // TODO: Add Thumb relocations.
449 uint32_t *TargetPtr =
450 reinterpret_cast<uint32_t *>(Section.getAddressWithOffset(Offset));
451 uint32_t FinalAddress = Section.getLoadAddressWithOffset(Offset) & 0xFFFFFFFF;
454 DEBUG(dbgs() << "resolveARMRelocation, LocalAddress: "
455 << Section.getAddressWithOffset(Offset)
456 << " FinalAddress: " << format("%p", FinalAddress) << " Value: "
457 << format("%x", Value) << " Type: " << format("%x", Type)
458 << " Addend: " << format("%x", Addend) << "\n");
462 llvm_unreachable("Not implemented relocation type!");
464 case ELF::R_ARM_NONE:
466 case ELF::R_ARM_PREL31:
467 case ELF::R_ARM_TARGET1:
468 case ELF::R_ARM_ABS32:
471 // Write first 16 bit of 32 bit value to the mov instruction.
472 // Last 4 bit should be shifted.
473 case ELF::R_ARM_MOVW_ABS_NC:
474 case ELF::R_ARM_MOVT_ABS:
475 if (Type == ELF::R_ARM_MOVW_ABS_NC)
476 Value = Value & 0xFFFF;
477 else if (Type == ELF::R_ARM_MOVT_ABS)
478 Value = (Value >> 16) & 0xFFFF;
479 *TargetPtr &= ~0x000F0FFF;
480 *TargetPtr |= Value & 0xFFF;
481 *TargetPtr |= ((Value >> 12) & 0xF) << 16;
483 // Write 24 bit relative value to the branch instruction.
484 case ELF::R_ARM_PC24: // Fall through.
485 case ELF::R_ARM_CALL: // Fall through.
486 case ELF::R_ARM_JUMP24:
487 int32_t RelValue = static_cast<int32_t>(Value - FinalAddress - 8);
488 RelValue = (RelValue & 0x03FFFFFC) >> 2;
489 assert((*TargetPtr & 0xFFFFFF) == 0xFFFFFE);
490 *TargetPtr &= 0xFF000000;
491 *TargetPtr |= RelValue;
496 void RuntimeDyldELF::resolveMIPSRelocation(const SectionEntry &Section,
497 uint64_t Offset, uint32_t Value,
498 uint32_t Type, int32_t Addend) {
499 uint8_t *TargetPtr = Section.getAddressWithOffset(Offset);
502 DEBUG(dbgs() << "resolveMIPSRelocation, LocalAddress: "
503 << Section.getAddressWithOffset(Offset) << " FinalAddress: "
504 << format("%p", Section.getLoadAddressWithOffset(Offset))
505 << " Value: " << format("%x", Value)
506 << " Type: " << format("%x", Type)
507 << " Addend: " << format("%x", Addend) << "\n");
509 uint32_t Insn = readBytesUnaligned(TargetPtr, 4);
513 llvm_unreachable("Not implemented relocation type!");
516 writeBytesUnaligned(Value, TargetPtr, 4);
520 Insn |= (Value & 0x0fffffff) >> 2;
521 writeBytesUnaligned(Insn, TargetPtr, 4);
523 case ELF::R_MIPS_HI16:
524 // Get the higher 16-bits. Also add 1 if bit 15 is 1.
526 Insn |= ((Value + 0x8000) >> 16) & 0xffff;
527 writeBytesUnaligned(Insn, TargetPtr, 4);
529 case ELF::R_MIPS_LO16:
531 Insn |= Value & 0xffff;
532 writeBytesUnaligned(Insn, TargetPtr, 4);
534 case ELF::R_MIPS_PC32: {
535 uint32_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
536 writeBytesUnaligned(Value - FinalAddress, (uint8_t *)TargetPtr, 4);
539 case ELF::R_MIPS_PC16: {
540 uint32_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
542 Insn |= ((Value - FinalAddress) >> 2) & 0xffff;
543 writeBytesUnaligned(Insn, TargetPtr, 4);
546 case ELF::R_MIPS_PC19_S2: {
547 uint32_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
549 Insn |= ((Value - (FinalAddress & ~0x3)) >> 2) & 0x7ffff;
550 writeBytesUnaligned(Insn, TargetPtr, 4);
553 case ELF::R_MIPS_PC21_S2: {
554 uint32_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
556 Insn |= ((Value - FinalAddress) >> 2) & 0x1fffff;
557 writeBytesUnaligned(Insn, TargetPtr, 4);
560 case ELF::R_MIPS_PC26_S2: {
561 uint32_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
563 Insn |= ((Value - FinalAddress) >> 2) & 0x3ffffff;
564 writeBytesUnaligned(Insn, TargetPtr, 4);
567 case ELF::R_MIPS_PCHI16: {
568 uint32_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
570 Insn |= ((Value - FinalAddress + 0x8000) >> 16) & 0xffff;
571 writeBytesUnaligned(Insn, TargetPtr, 4);
574 case ELF::R_MIPS_PCLO16: {
575 uint32_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
577 Insn |= (Value - FinalAddress) & 0xffff;
578 writeBytesUnaligned(Insn, TargetPtr, 4);
584 void RuntimeDyldELF::setMipsABI(const ObjectFile &Obj) {
585 if (Arch == Triple::UnknownArch ||
586 !StringRef(Triple::getArchTypePrefix(Arch)).equals("mips")) {
587 IsMipsO32ABI = false;
588 IsMipsN64ABI = false;
592 Obj.getPlatformFlags(AbiVariant);
593 IsMipsO32ABI = AbiVariant & ELF::EF_MIPS_ABI_O32;
594 IsMipsN64ABI = Obj.getFileFormatName().equals("ELF64-mips");
595 if (AbiVariant & ELF::EF_MIPS_ABI2)
596 llvm_unreachable("Mips N32 ABI is not supported yet");
599 void RuntimeDyldELF::resolveMIPS64Relocation(const SectionEntry &Section,
600 uint64_t Offset, uint64_t Value,
601 uint32_t Type, int64_t Addend,
604 uint32_t r_type = Type & 0xff;
605 uint32_t r_type2 = (Type >> 8) & 0xff;
606 uint32_t r_type3 = (Type >> 16) & 0xff;
608 // RelType is used to keep information for which relocation type we are
609 // applying relocation.
610 uint32_t RelType = r_type;
611 int64_t CalculatedValue = evaluateMIPS64Relocation(Section, Offset, Value,
613 SymOffset, SectionID);
614 if (r_type2 != ELF::R_MIPS_NONE) {
616 CalculatedValue = evaluateMIPS64Relocation(Section, Offset, 0, RelType,
617 CalculatedValue, SymOffset,
620 if (r_type3 != ELF::R_MIPS_NONE) {
622 CalculatedValue = evaluateMIPS64Relocation(Section, Offset, 0, RelType,
623 CalculatedValue, SymOffset,
626 applyMIPS64Relocation(Section.getAddressWithOffset(Offset), CalculatedValue,
631 RuntimeDyldELF::evaluateMIPS64Relocation(const SectionEntry &Section,
632 uint64_t Offset, uint64_t Value,
633 uint32_t Type, int64_t Addend,
634 uint64_t SymOffset, SID SectionID) {
636 DEBUG(dbgs() << "evaluateMIPS64Relocation, LocalAddress: 0x"
637 << format("%llx", Section.getAddressWithOffset(Offset))
638 << " FinalAddress: 0x"
639 << format("%llx", Section.getLoadAddressWithOffset(Offset))
640 << " Value: 0x" << format("%llx", Value) << " Type: 0x"
641 << format("%x", Type) << " Addend: 0x" << format("%llx", Addend)
642 << " SymOffset: " << format("%x", SymOffset) << "\n");
646 llvm_unreachable("Not implemented relocation type!");
648 case ELF::R_MIPS_JALR:
649 case ELF::R_MIPS_NONE:
653 return Value + Addend;
655 return ((Value + Addend) >> 2) & 0x3ffffff;
656 case ELF::R_MIPS_GPREL16: {
657 uint64_t GOTAddr = getSectionLoadAddress(SectionToGOTMap[SectionID]);
658 return Value + Addend - (GOTAddr + 0x7ff0);
660 case ELF::R_MIPS_SUB:
661 return Value - Addend;
662 case ELF::R_MIPS_HI16:
663 // Get the higher 16-bits. Also add 1 if bit 15 is 1.
664 return ((Value + Addend + 0x8000) >> 16) & 0xffff;
665 case ELF::R_MIPS_LO16:
666 return (Value + Addend) & 0xffff;
667 case ELF::R_MIPS_CALL16:
668 case ELF::R_MIPS_GOT_DISP:
669 case ELF::R_MIPS_GOT_PAGE: {
670 uint8_t *LocalGOTAddr =
671 getSectionAddress(SectionToGOTMap[SectionID]) + SymOffset;
672 uint64_t GOTEntry = readBytesUnaligned(LocalGOTAddr, 8);
675 if (Type == ELF::R_MIPS_GOT_PAGE)
676 Value = (Value + 0x8000) & ~0xffff;
679 assert(GOTEntry == Value &&
680 "GOT entry has two different addresses.");
682 writeBytesUnaligned(Value, LocalGOTAddr, 8);
684 return (SymOffset - 0x7ff0) & 0xffff;
686 case ELF::R_MIPS_GOT_OFST: {
687 int64_t page = (Value + Addend + 0x8000) & ~0xffff;
688 return (Value + Addend - page) & 0xffff;
690 case ELF::R_MIPS_GPREL32: {
691 uint64_t GOTAddr = getSectionLoadAddress(SectionToGOTMap[SectionID]);
692 return Value + Addend - (GOTAddr + 0x7ff0);
694 case ELF::R_MIPS_PC16: {
695 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
696 return ((Value + Addend - FinalAddress) >> 2) & 0xffff;
698 case ELF::R_MIPS_PC32: {
699 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
700 return Value + Addend - FinalAddress;
702 case ELF::R_MIPS_PC18_S3: {
703 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
704 return ((Value + Addend - (FinalAddress & ~0x7)) >> 3) & 0x3ffff;
706 case ELF::R_MIPS_PC19_S2: {
707 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
708 return ((Value + Addend - (FinalAddress & ~0x3)) >> 2) & 0x7ffff;
710 case ELF::R_MIPS_PC21_S2: {
711 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
712 return ((Value + Addend - FinalAddress) >> 2) & 0x1fffff;
714 case ELF::R_MIPS_PC26_S2: {
715 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
716 return ((Value + Addend - FinalAddress) >> 2) & 0x3ffffff;
718 case ELF::R_MIPS_PCHI16: {
719 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
720 return ((Value + Addend - FinalAddress + 0x8000) >> 16) & 0xffff;
722 case ELF::R_MIPS_PCLO16: {
723 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
724 return (Value + Addend - FinalAddress) & 0xffff;
730 void RuntimeDyldELF::applyMIPS64Relocation(uint8_t *TargetPtr,
731 int64_t CalculatedValue,
733 uint32_t Insn = readBytesUnaligned(TargetPtr, 4);
739 case ELF::R_MIPS_GPREL32:
740 case ELF::R_MIPS_PC32:
741 writeBytesUnaligned(CalculatedValue & 0xffffffff, TargetPtr, 4);
744 case ELF::R_MIPS_SUB:
745 writeBytesUnaligned(CalculatedValue, TargetPtr, 8);
748 case ELF::R_MIPS_PC26_S2:
749 Insn = (Insn & 0xfc000000) | CalculatedValue;
750 writeBytesUnaligned(Insn, TargetPtr, 4);
752 case ELF::R_MIPS_GPREL16:
753 Insn = (Insn & 0xffff0000) | (CalculatedValue & 0xffff);
754 writeBytesUnaligned(Insn, TargetPtr, 4);
756 case ELF::R_MIPS_HI16:
757 case ELF::R_MIPS_LO16:
758 case ELF::R_MIPS_PCHI16:
759 case ELF::R_MIPS_PCLO16:
760 case ELF::R_MIPS_PC16:
761 case ELF::R_MIPS_CALL16:
762 case ELF::R_MIPS_GOT_DISP:
763 case ELF::R_MIPS_GOT_PAGE:
764 case ELF::R_MIPS_GOT_OFST:
765 Insn = (Insn & 0xffff0000) | CalculatedValue;
766 writeBytesUnaligned(Insn, TargetPtr, 4);
768 case ELF::R_MIPS_PC18_S3:
769 Insn = (Insn & 0xfffc0000) | CalculatedValue;
770 writeBytesUnaligned(Insn, TargetPtr, 4);
772 case ELF::R_MIPS_PC19_S2:
773 Insn = (Insn & 0xfff80000) | CalculatedValue;
774 writeBytesUnaligned(Insn, TargetPtr, 4);
776 case ELF::R_MIPS_PC21_S2:
777 Insn = (Insn & 0xffe00000) | CalculatedValue;
778 writeBytesUnaligned(Insn, TargetPtr, 4);
783 // Return the .TOC. section and offset.
784 void RuntimeDyldELF::findPPC64TOCSection(const ELFObjectFileBase &Obj,
785 ObjSectionToIDMap &LocalSections,
786 RelocationValueRef &Rel) {
787 // Set a default SectionID in case we do not find a TOC section below.
788 // This may happen for references to TOC base base (sym@toc, .odp
789 // relocation) without a .toc directive. In this case just use the
790 // first section (which is usually the .odp) since the code won't
791 // reference the .toc base directly.
792 Rel.SymbolName = nullptr;
795 // The TOC consists of sections .got, .toc, .tocbss, .plt in that
796 // order. The TOC starts where the first of these sections starts.
797 for (auto &Section: Obj.sections()) {
798 StringRef SectionName;
799 check(Section.getName(SectionName));
801 if (SectionName == ".got"
802 || SectionName == ".toc"
803 || SectionName == ".tocbss"
804 || SectionName == ".plt") {
805 Rel.SectionID = findOrEmitSection(Obj, Section, false, LocalSections);
810 // Per the ppc64-elf-linux ABI, The TOC base is TOC value plus 0x8000
811 // thus permitting a full 64 Kbytes segment.
815 // Returns the sections and offset associated with the ODP entry referenced
817 void RuntimeDyldELF::findOPDEntrySection(const ELFObjectFileBase &Obj,
818 ObjSectionToIDMap &LocalSections,
819 RelocationValueRef &Rel) {
820 // Get the ELF symbol value (st_value) to compare with Relocation offset in
822 for (section_iterator si = Obj.section_begin(), se = Obj.section_end();
824 section_iterator RelSecI = si->getRelocatedSection();
825 if (RelSecI == Obj.section_end())
828 StringRef RelSectionName;
829 check(RelSecI->getName(RelSectionName));
830 if (RelSectionName != ".opd")
833 for (elf_relocation_iterator i = si->relocation_begin(),
834 e = si->relocation_end();
836 // The R_PPC64_ADDR64 relocation indicates the first field
838 uint64_t TypeFunc = i->getType();
839 if (TypeFunc != ELF::R_PPC64_ADDR64) {
844 uint64_t TargetSymbolOffset = i->getOffset();
845 symbol_iterator TargetSymbol = i->getSymbol();
846 ErrorOr<int64_t> AddendOrErr = i->getAddend();
847 Check(AddendOrErr.getError());
848 int64_t Addend = *AddendOrErr;
854 // Just check if following relocation is a R_PPC64_TOC
855 uint64_t TypeTOC = i->getType();
856 if (TypeTOC != ELF::R_PPC64_TOC)
859 // Finally compares the Symbol value and the target symbol offset
860 // to check if this .opd entry refers to the symbol the relocation
862 if (Rel.Addend != (int64_t)TargetSymbolOffset)
865 ErrorOr<section_iterator> TSIOrErr = TargetSymbol->getSection();
866 check(TSIOrErr.getError());
867 section_iterator tsi = *TSIOrErr;
868 bool IsCode = tsi->isText();
869 Rel.SectionID = findOrEmitSection(Obj, (*tsi), IsCode, LocalSections);
870 Rel.Addend = (intptr_t)Addend;
874 llvm_unreachable("Attempting to get address of ODP entry!");
877 // Relocation masks following the #lo(value), #hi(value), #ha(value),
878 // #higher(value), #highera(value), #highest(value), and #highesta(value)
879 // macros defined in section 4.5.1. Relocation Types of the PPC-elf64abi
882 static inline uint16_t applyPPClo(uint64_t value) { return value & 0xffff; }
884 static inline uint16_t applyPPChi(uint64_t value) {
885 return (value >> 16) & 0xffff;
888 static inline uint16_t applyPPCha (uint64_t value) {
889 return ((value + 0x8000) >> 16) & 0xffff;
892 static inline uint16_t applyPPChigher(uint64_t value) {
893 return (value >> 32) & 0xffff;
896 static inline uint16_t applyPPChighera (uint64_t value) {
897 return ((value + 0x8000) >> 32) & 0xffff;
900 static inline uint16_t applyPPChighest(uint64_t value) {
901 return (value >> 48) & 0xffff;
904 static inline uint16_t applyPPChighesta (uint64_t value) {
905 return ((value + 0x8000) >> 48) & 0xffff;
908 void RuntimeDyldELF::resolvePPC32Relocation(const SectionEntry &Section,
909 uint64_t Offset, uint64_t Value,
910 uint32_t Type, int64_t Addend) {
911 uint8_t *LocalAddress = Section.getAddressWithOffset(Offset);
914 llvm_unreachable("Relocation type not implemented yet!");
916 case ELF::R_PPC_ADDR16_LO:
917 writeInt16BE(LocalAddress, applyPPClo(Value + Addend));
919 case ELF::R_PPC_ADDR16_HI:
920 writeInt16BE(LocalAddress, applyPPChi(Value + Addend));
922 case ELF::R_PPC_ADDR16_HA:
923 writeInt16BE(LocalAddress, applyPPCha(Value + Addend));
928 void RuntimeDyldELF::resolvePPC64Relocation(const SectionEntry &Section,
929 uint64_t Offset, uint64_t Value,
930 uint32_t Type, int64_t Addend) {
931 uint8_t *LocalAddress = Section.getAddressWithOffset(Offset);
934 llvm_unreachable("Relocation type not implemented yet!");
936 case ELF::R_PPC64_ADDR16:
937 writeInt16BE(LocalAddress, applyPPClo(Value + Addend));
939 case ELF::R_PPC64_ADDR16_DS:
940 writeInt16BE(LocalAddress, applyPPClo(Value + Addend) & ~3);
942 case ELF::R_PPC64_ADDR16_LO:
943 writeInt16BE(LocalAddress, applyPPClo(Value + Addend));
945 case ELF::R_PPC64_ADDR16_LO_DS:
946 writeInt16BE(LocalAddress, applyPPClo(Value + Addend) & ~3);
948 case ELF::R_PPC64_ADDR16_HI:
949 writeInt16BE(LocalAddress, applyPPChi(Value + Addend));
951 case ELF::R_PPC64_ADDR16_HA:
952 writeInt16BE(LocalAddress, applyPPCha(Value + Addend));
954 case ELF::R_PPC64_ADDR16_HIGHER:
955 writeInt16BE(LocalAddress, applyPPChigher(Value + Addend));
957 case ELF::R_PPC64_ADDR16_HIGHERA:
958 writeInt16BE(LocalAddress, applyPPChighera(Value + Addend));
960 case ELF::R_PPC64_ADDR16_HIGHEST:
961 writeInt16BE(LocalAddress, applyPPChighest(Value + Addend));
963 case ELF::R_PPC64_ADDR16_HIGHESTA:
964 writeInt16BE(LocalAddress, applyPPChighesta(Value + Addend));
966 case ELF::R_PPC64_ADDR14: {
967 assert(((Value + Addend) & 3) == 0);
968 // Preserve the AA/LK bits in the branch instruction
969 uint8_t aalk = *(LocalAddress + 3);
970 writeInt16BE(LocalAddress + 2, (aalk & 3) | ((Value + Addend) & 0xfffc));
972 case ELF::R_PPC64_REL16_LO: {
973 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
974 uint64_t Delta = Value - FinalAddress + Addend;
975 writeInt16BE(LocalAddress, applyPPClo(Delta));
977 case ELF::R_PPC64_REL16_HI: {
978 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
979 uint64_t Delta = Value - FinalAddress + Addend;
980 writeInt16BE(LocalAddress, applyPPChi(Delta));
982 case ELF::R_PPC64_REL16_HA: {
983 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
984 uint64_t Delta = Value - FinalAddress + Addend;
985 writeInt16BE(LocalAddress, applyPPCha(Delta));
987 case ELF::R_PPC64_ADDR32: {
988 int32_t Result = static_cast<int32_t>(Value + Addend);
989 if (SignExtend32<32>(Result) != Result)
990 llvm_unreachable("Relocation R_PPC64_ADDR32 overflow");
991 writeInt32BE(LocalAddress, Result);
993 case ELF::R_PPC64_REL24: {
994 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
995 int32_t delta = static_cast<int32_t>(Value - FinalAddress + Addend);
996 if (SignExtend32<26>(delta) != delta)
997 llvm_unreachable("Relocation R_PPC64_REL24 overflow");
998 // Generates a 'bl <address>' instruction
999 writeInt32BE(LocalAddress, 0x48000001 | (delta & 0x03FFFFFC));
1001 case ELF::R_PPC64_REL32: {
1002 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
1003 int32_t delta = static_cast<int32_t>(Value - FinalAddress + Addend);
1004 if (SignExtend32<32>(delta) != delta)
1005 llvm_unreachable("Relocation R_PPC64_REL32 overflow");
1006 writeInt32BE(LocalAddress, delta);
1008 case ELF::R_PPC64_REL64: {
1009 uint64_t FinalAddress = Section.getLoadAddressWithOffset(Offset);
1010 uint64_t Delta = Value - FinalAddress + Addend;
1011 writeInt64BE(LocalAddress, Delta);
1013 case ELF::R_PPC64_ADDR64:
1014 writeInt64BE(LocalAddress, Value + Addend);
1019 void RuntimeDyldELF::resolveSystemZRelocation(const SectionEntry &Section,
1020 uint64_t Offset, uint64_t Value,
1021 uint32_t Type, int64_t Addend) {
1022 uint8_t *LocalAddress = Section.getAddressWithOffset(Offset);
1025 llvm_unreachable("Relocation type not implemented yet!");
1027 case ELF::R_390_PC16DBL:
1028 case ELF::R_390_PLT16DBL: {
1029 int64_t Delta = (Value + Addend) - Section.getLoadAddressWithOffset(Offset);
1030 assert(int16_t(Delta / 2) * 2 == Delta && "R_390_PC16DBL overflow");
1031 writeInt16BE(LocalAddress, Delta / 2);
1034 case ELF::R_390_PC32DBL:
1035 case ELF::R_390_PLT32DBL: {
1036 int64_t Delta = (Value + Addend) - Section.getLoadAddressWithOffset(Offset);
1037 assert(int32_t(Delta / 2) * 2 == Delta && "R_390_PC32DBL overflow");
1038 writeInt32BE(LocalAddress, Delta / 2);
1041 case ELF::R_390_PC32: {
1042 int64_t Delta = (Value + Addend) - Section.getLoadAddressWithOffset(Offset);
1043 assert(int32_t(Delta) == Delta && "R_390_PC32 overflow");
1044 writeInt32BE(LocalAddress, Delta);
1048 writeInt64BE(LocalAddress, Value + Addend);
1053 // The target location for the relocation is described by RE.SectionID and
1054 // RE.Offset. RE.SectionID can be used to find the SectionEntry. Each
1055 // SectionEntry has three members describing its location.
1056 // SectionEntry::Address is the address at which the section has been loaded
1057 // into memory in the current (host) process. SectionEntry::LoadAddress is the
1058 // address that the section will have in the target process.
1059 // SectionEntry::ObjAddress is the address of the bits for this section in the
1060 // original emitted object image (also in the current address space).
1062 // Relocations will be applied as if the section were loaded at
1063 // SectionEntry::LoadAddress, but they will be applied at an address based
1064 // on SectionEntry::Address. SectionEntry::ObjAddress will be used to refer to
1065 // Target memory contents if they are required for value calculations.
1067 // The Value parameter here is the load address of the symbol for the
1068 // relocation to be applied. For relocations which refer to symbols in the
1069 // current object Value will be the LoadAddress of the section in which
1070 // the symbol resides (RE.Addend provides additional information about the
1071 // symbol location). For external symbols, Value will be the address of the
1072 // symbol in the target address space.
1073 void RuntimeDyldELF::resolveRelocation(const RelocationEntry &RE,
1075 const SectionEntry &Section = Sections[RE.SectionID];
1076 return resolveRelocation(Section, RE.Offset, Value, RE.RelType, RE.Addend,
1077 RE.SymOffset, RE.SectionID);
1080 void RuntimeDyldELF::resolveRelocation(const SectionEntry &Section,
1081 uint64_t Offset, uint64_t Value,
1082 uint32_t Type, int64_t Addend,
1083 uint64_t SymOffset, SID SectionID) {
1085 case Triple::x86_64:
1086 resolveX86_64Relocation(Section, Offset, Value, Type, Addend, SymOffset);
1089 resolveX86Relocation(Section, Offset, (uint32_t)(Value & 0xffffffffL), Type,
1090 (uint32_t)(Addend & 0xffffffffL));
1092 case Triple::aarch64:
1093 case Triple::aarch64_be:
1094 resolveAArch64Relocation(Section, Offset, Value, Type, Addend);
1096 case Triple::arm: // Fall through.
1099 case Triple::thumbeb:
1100 resolveARMRelocation(Section, Offset, (uint32_t)(Value & 0xffffffffL), Type,
1101 (uint32_t)(Addend & 0xffffffffL));
1103 case Triple::mips: // Fall through.
1104 case Triple::mipsel:
1105 case Triple::mips64:
1106 case Triple::mips64el:
1108 resolveMIPSRelocation(Section, Offset, (uint32_t)(Value & 0xffffffffL),
1109 Type, (uint32_t)(Addend & 0xffffffffL));
1110 else if (IsMipsN64ABI)
1111 resolveMIPS64Relocation(Section, Offset, Value, Type, Addend, SymOffset,
1114 llvm_unreachable("Mips ABI not handled");
1117 resolvePPC32Relocation(Section, Offset, Value, Type, Addend);
1119 case Triple::ppc64: // Fall through.
1120 case Triple::ppc64le:
1121 resolvePPC64Relocation(Section, Offset, Value, Type, Addend);
1123 case Triple::systemz:
1124 resolveSystemZRelocation(Section, Offset, Value, Type, Addend);
1127 llvm_unreachable("Unsupported CPU type!");
1131 void *RuntimeDyldELF::computePlaceholderAddress(unsigned SectionID, uint64_t Offset) const {
1132 return (void *)(Sections[SectionID].getObjAddress() + Offset);
1135 void RuntimeDyldELF::processSimpleRelocation(unsigned SectionID, uint64_t Offset, unsigned RelType, RelocationValueRef Value) {
1136 RelocationEntry RE(SectionID, Offset, RelType, Value.Addend, Value.Offset);
1137 if (Value.SymbolName)
1138 addRelocationForSymbol(RE, Value.SymbolName);
1140 addRelocationForSection(RE, Value.SectionID);
1143 uint32_t RuntimeDyldELF::getMatchingLoRelocation(uint32_t RelType,
1144 bool IsLocal) const {
1146 case ELF::R_MICROMIPS_GOT16:
1148 return ELF::R_MICROMIPS_LO16;
1150 case ELF::R_MICROMIPS_HI16:
1151 return ELF::R_MICROMIPS_LO16;
1152 case ELF::R_MIPS_GOT16:
1154 return ELF::R_MIPS_LO16;
1156 case ELF::R_MIPS_HI16:
1157 return ELF::R_MIPS_LO16;
1158 case ELF::R_MIPS_PCHI16:
1159 return ELF::R_MIPS_PCLO16;
1163 return ELF::R_MIPS_NONE;
1166 relocation_iterator RuntimeDyldELF::processRelocationRef(
1167 unsigned SectionID, relocation_iterator RelI, const ObjectFile &O,
1168 ObjSectionToIDMap &ObjSectionToID, StubMap &Stubs) {
1169 const auto &Obj = cast<ELFObjectFileBase>(O);
1170 uint64_t RelType = RelI->getType();
1171 ErrorOr<int64_t> AddendOrErr = ELFRelocationRef(*RelI).getAddend();
1172 int64_t Addend = AddendOrErr ? *AddendOrErr : 0;
1173 elf_symbol_iterator Symbol = RelI->getSymbol();
1175 // Obtain the symbol name which is referenced in the relocation
1176 StringRef TargetName;
1177 if (Symbol != Obj.symbol_end()) {
1178 ErrorOr<StringRef> TargetNameOrErr = Symbol->getName();
1179 if (std::error_code EC = TargetNameOrErr.getError())
1180 report_fatal_error(EC.message());
1181 TargetName = *TargetNameOrErr;
1183 DEBUG(dbgs() << "\t\tRelType: " << RelType << " Addend: " << Addend
1184 << " TargetName: " << TargetName << "\n");
1185 RelocationValueRef Value;
1186 // First search for the symbol in the local symbol table
1187 SymbolRef::Type SymType = SymbolRef::ST_Unknown;
1189 // Search for the symbol in the global symbol table
1190 RTDyldSymbolTable::const_iterator gsi = GlobalSymbolTable.end();
1191 if (Symbol != Obj.symbol_end()) {
1192 gsi = GlobalSymbolTable.find(TargetName.data());
1193 SymType = Symbol->getType();
1195 if (gsi != GlobalSymbolTable.end()) {
1196 const auto &SymInfo = gsi->second;
1197 Value.SectionID = SymInfo.getSectionID();
1198 Value.Offset = SymInfo.getOffset();
1199 Value.Addend = SymInfo.getOffset() + Addend;
1202 case SymbolRef::ST_Debug: {
1203 // TODO: Now ELF SymbolRef::ST_Debug = STT_SECTION, it's not obviously
1204 // and can be changed by another developers. Maybe best way is add
1205 // a new symbol type ST_Section to SymbolRef and use it.
1206 section_iterator si = *Symbol->getSection();
1207 if (si == Obj.section_end())
1208 llvm_unreachable("Symbol section not found, bad object file format!");
1209 DEBUG(dbgs() << "\t\tThis is section symbol\n");
1210 bool isCode = si->isText();
1211 Value.SectionID = findOrEmitSection(Obj, (*si), isCode, ObjSectionToID);
1212 Value.Addend = Addend;
1215 case SymbolRef::ST_Data:
1216 case SymbolRef::ST_Unknown: {
1217 Value.SymbolName = TargetName.data();
1218 Value.Addend = Addend;
1220 // Absolute relocations will have a zero symbol ID (STN_UNDEF), which
1221 // will manifest here as a NULL symbol name.
1222 // We can set this as a valid (but empty) symbol name, and rely
1223 // on addRelocationForSymbol to handle this.
1224 if (!Value.SymbolName)
1225 Value.SymbolName = "";
1229 llvm_unreachable("Unresolved symbol type!");
1234 uint64_t Offset = RelI->getOffset();
1236 DEBUG(dbgs() << "\t\tSectionID: " << SectionID << " Offset: " << Offset
1238 if ((Arch == Triple::aarch64 || Arch == Triple::aarch64_be) &&
1239 (RelType == ELF::R_AARCH64_CALL26 || RelType == ELF::R_AARCH64_JUMP26)) {
1240 // This is an AArch64 branch relocation, need to use a stub function.
1241 DEBUG(dbgs() << "\t\tThis is an AArch64 branch relocation.");
1242 SectionEntry &Section = Sections[SectionID];
1244 // Look for an existing stub.
1245 StubMap::const_iterator i = Stubs.find(Value);
1246 if (i != Stubs.end()) {
1247 resolveRelocation(Section, Offset,
1248 (uint64_t)Section.getAddressWithOffset(i->second),
1250 DEBUG(dbgs() << " Stub function found\n");
1252 // Create a new stub function.
1253 DEBUG(dbgs() << " Create a new stub function\n");
1254 Stubs[Value] = Section.getStubOffset();
1255 uint8_t *StubTargetAddr = createStubFunction(
1256 Section.getAddressWithOffset(Section.getStubOffset()));
1258 RelocationEntry REmovz_g3(SectionID,
1259 StubTargetAddr - Section.getAddress(),
1260 ELF::R_AARCH64_MOVW_UABS_G3, Value.Addend);
1261 RelocationEntry REmovk_g2(SectionID, StubTargetAddr -
1262 Section.getAddressWithOffset(4),
1263 ELF::R_AARCH64_MOVW_UABS_G2_NC, Value.Addend);
1264 RelocationEntry REmovk_g1(SectionID, StubTargetAddr -
1265 Section.getAddressWithOffset(8),
1266 ELF::R_AARCH64_MOVW_UABS_G1_NC, Value.Addend);
1267 RelocationEntry REmovk_g0(SectionID, StubTargetAddr -
1268 Section.getAddressWithOffset(12),
1269 ELF::R_AARCH64_MOVW_UABS_G0_NC, Value.Addend);
1271 if (Value.SymbolName) {
1272 addRelocationForSymbol(REmovz_g3, Value.SymbolName);
1273 addRelocationForSymbol(REmovk_g2, Value.SymbolName);
1274 addRelocationForSymbol(REmovk_g1, Value.SymbolName);
1275 addRelocationForSymbol(REmovk_g0, Value.SymbolName);
1277 addRelocationForSection(REmovz_g3, Value.SectionID);
1278 addRelocationForSection(REmovk_g2, Value.SectionID);
1279 addRelocationForSection(REmovk_g1, Value.SectionID);
1280 addRelocationForSection(REmovk_g0, Value.SectionID);
1282 resolveRelocation(Section, Offset,
1283 reinterpret_cast<uint64_t>(Section.getAddressWithOffset(
1284 Section.getStubOffset())),
1286 Section.advanceStubOffset(getMaxStubSize());
1288 } else if (Arch == Triple::arm) {
1289 if (RelType == ELF::R_ARM_PC24 || RelType == ELF::R_ARM_CALL ||
1290 RelType == ELF::R_ARM_JUMP24) {
1291 // This is an ARM branch relocation, need to use a stub function.
1292 DEBUG(dbgs() << "\t\tThis is an ARM branch relocation.");
1293 SectionEntry &Section = Sections[SectionID];
1295 // Look for an existing stub.
1296 StubMap::const_iterator i = Stubs.find(Value);
1297 if (i != Stubs.end()) {
1300 reinterpret_cast<uint64_t>(Section.getAddressWithOffset(i->second)),
1302 DEBUG(dbgs() << " Stub function found\n");
1304 // Create a new stub function.
1305 DEBUG(dbgs() << " Create a new stub function\n");
1306 Stubs[Value] = Section.getStubOffset();
1307 uint8_t *StubTargetAddr = createStubFunction(
1308 Section.getAddressWithOffset(Section.getStubOffset()));
1309 RelocationEntry RE(SectionID, StubTargetAddr - Section.getAddress(),
1310 ELF::R_ARM_ABS32, Value.Addend);
1311 if (Value.SymbolName)
1312 addRelocationForSymbol(RE, Value.SymbolName);
1314 addRelocationForSection(RE, Value.SectionID);
1316 resolveRelocation(Section, Offset, reinterpret_cast<uint64_t>(
1317 Section.getAddressWithOffset(
1318 Section.getStubOffset())),
1320 Section.advanceStubOffset(getMaxStubSize());
1323 uint32_t *Placeholder =
1324 reinterpret_cast<uint32_t*>(computePlaceholderAddress(SectionID, Offset));
1325 if (RelType == ELF::R_ARM_PREL31 || RelType == ELF::R_ARM_TARGET1 ||
1326 RelType == ELF::R_ARM_ABS32) {
1327 Value.Addend += *Placeholder;
1328 } else if (RelType == ELF::R_ARM_MOVW_ABS_NC || RelType == ELF::R_ARM_MOVT_ABS) {
1329 // See ELF for ARM documentation
1330 Value.Addend += (int16_t)((*Placeholder & 0xFFF) | (((*Placeholder >> 16) & 0xF) << 12));
1332 processSimpleRelocation(SectionID, Offset, RelType, Value);
1334 } else if (IsMipsO32ABI) {
1335 uint8_t *Placeholder = reinterpret_cast<uint8_t *>(
1336 computePlaceholderAddress(SectionID, Offset));
1337 uint32_t Opcode = readBytesUnaligned(Placeholder, 4);
1338 if (RelType == ELF::R_MIPS_26) {
1339 // This is an Mips branch relocation, need to use a stub function.
1340 DEBUG(dbgs() << "\t\tThis is a Mips branch relocation.");
1341 SectionEntry &Section = Sections[SectionID];
1343 // Extract the addend from the instruction.
1344 // We shift up by two since the Value will be down shifted again
1345 // when applying the relocation.
1346 uint32_t Addend = (Opcode & 0x03ffffff) << 2;
1348 Value.Addend += Addend;
1350 // Look up for existing stub.
1351 StubMap::const_iterator i = Stubs.find(Value);
1352 if (i != Stubs.end()) {
1353 RelocationEntry RE(SectionID, Offset, RelType, i->second);
1354 addRelocationForSection(RE, SectionID);
1355 DEBUG(dbgs() << " Stub function found\n");
1357 // Create a new stub function.
1358 DEBUG(dbgs() << " Create a new stub function\n");
1359 Stubs[Value] = Section.getStubOffset();
1360 uint8_t *StubTargetAddr = createStubFunction(
1361 Section.getAddressWithOffset(Section.getStubOffset()));
1363 // Creating Hi and Lo relocations for the filled stub instructions.
1364 RelocationEntry REHi(SectionID, StubTargetAddr - Section.getAddress(),
1365 ELF::R_MIPS_HI16, Value.Addend);
1366 RelocationEntry RELo(SectionID,
1367 StubTargetAddr - Section.getAddressWithOffset(4),
1368 ELF::R_MIPS_LO16, Value.Addend);
1370 if (Value.SymbolName) {
1371 addRelocationForSymbol(REHi, Value.SymbolName);
1372 addRelocationForSymbol(RELo, Value.SymbolName);
1375 addRelocationForSection(REHi, Value.SectionID);
1376 addRelocationForSection(RELo, Value.SectionID);
1379 RelocationEntry RE(SectionID, Offset, RelType, Section.getStubOffset());
1380 addRelocationForSection(RE, SectionID);
1381 Section.advanceStubOffset(getMaxStubSize());
1383 } else if (RelType == ELF::R_MIPS_HI16 || RelType == ELF::R_MIPS_PCHI16) {
1384 int64_t Addend = (Opcode & 0x0000ffff) << 16;
1385 RelocationEntry RE(SectionID, Offset, RelType, Addend);
1386 PendingRelocs.push_back(std::make_pair(Value, RE));
1387 } else if (RelType == ELF::R_MIPS_LO16 || RelType == ELF::R_MIPS_PCLO16) {
1388 int64_t Addend = Value.Addend + SignExtend32<16>(Opcode & 0x0000ffff);
1389 for (auto I = PendingRelocs.begin(); I != PendingRelocs.end();) {
1390 const RelocationValueRef &MatchingValue = I->first;
1391 RelocationEntry &Reloc = I->second;
1392 if (MatchingValue == Value &&
1393 RelType == getMatchingLoRelocation(Reloc.RelType) &&
1394 SectionID == Reloc.SectionID) {
1395 Reloc.Addend += Addend;
1396 if (Value.SymbolName)
1397 addRelocationForSymbol(Reloc, Value.SymbolName);
1399 addRelocationForSection(Reloc, Value.SectionID);
1400 I = PendingRelocs.erase(I);
1404 RelocationEntry RE(SectionID, Offset, RelType, Addend);
1405 if (Value.SymbolName)
1406 addRelocationForSymbol(RE, Value.SymbolName);
1408 addRelocationForSection(RE, Value.SectionID);
1410 if (RelType == ELF::R_MIPS_32)
1411 Value.Addend += Opcode;
1412 else if (RelType == ELF::R_MIPS_PC16)
1413 Value.Addend += SignExtend32<18>((Opcode & 0x0000ffff) << 2);
1414 else if (RelType == ELF::R_MIPS_PC19_S2)
1415 Value.Addend += SignExtend32<21>((Opcode & 0x0007ffff) << 2);
1416 else if (RelType == ELF::R_MIPS_PC21_S2)
1417 Value.Addend += SignExtend32<23>((Opcode & 0x001fffff) << 2);
1418 else if (RelType == ELF::R_MIPS_PC26_S2)
1419 Value.Addend += SignExtend32<28>((Opcode & 0x03ffffff) << 2);
1420 processSimpleRelocation(SectionID, Offset, RelType, Value);
1422 } else if (IsMipsN64ABI) {
1423 uint32_t r_type = RelType & 0xff;
1424 RelocationEntry RE(SectionID, Offset, RelType, Value.Addend);
1425 if (r_type == ELF::R_MIPS_CALL16 || r_type == ELF::R_MIPS_GOT_PAGE
1426 || r_type == ELF::R_MIPS_GOT_DISP) {
1427 StringMap<uint64_t>::iterator i = GOTSymbolOffsets.find(TargetName);
1428 if (i != GOTSymbolOffsets.end())
1429 RE.SymOffset = i->second;
1431 RE.SymOffset = allocateGOTEntries(SectionID, 1);
1432 GOTSymbolOffsets[TargetName] = RE.SymOffset;
1435 if (Value.SymbolName)
1436 addRelocationForSymbol(RE, Value.SymbolName);
1438 addRelocationForSection(RE, Value.SectionID);
1439 } else if (Arch == Triple::ppc64 || Arch == Triple::ppc64le) {
1440 if (RelType == ELF::R_PPC64_REL24) {
1441 // Determine ABI variant in use for this object.
1442 unsigned AbiVariant;
1443 Obj.getPlatformFlags(AbiVariant);
1444 AbiVariant &= ELF::EF_PPC64_ABI;
1445 // A PPC branch relocation will need a stub function if the target is
1446 // an external symbol (Symbol::ST_Unknown) or if the target address
1447 // is not within the signed 24-bits branch address.
1448 SectionEntry &Section = Sections[SectionID];
1449 uint8_t *Target = Section.getAddressWithOffset(Offset);
1450 bool RangeOverflow = false;
1451 if (SymType != SymbolRef::ST_Unknown) {
1452 if (AbiVariant != 2) {
1453 // In the ELFv1 ABI, a function call may point to the .opd entry,
1454 // so the final symbol value is calculated based on the relocation
1455 // values in the .opd section.
1456 findOPDEntrySection(Obj, ObjSectionToID, Value);
1458 // In the ELFv2 ABI, a function symbol may provide a local entry
1459 // point, which must be used for direct calls.
1460 uint8_t SymOther = Symbol->getOther();
1461 Value.Addend += ELF::decodePPC64LocalEntryOffset(SymOther);
1463 uint8_t *RelocTarget =
1464 Sections[Value.SectionID].getAddressWithOffset(Value.Addend);
1465 int32_t delta = static_cast<int32_t>(Target - RelocTarget);
1466 // If it is within 26-bits branch range, just set the branch target
1467 if (SignExtend32<26>(delta) == delta) {
1468 RelocationEntry RE(SectionID, Offset, RelType, Value.Addend);
1469 if (Value.SymbolName)
1470 addRelocationForSymbol(RE, Value.SymbolName);
1472 addRelocationForSection(RE, Value.SectionID);
1474 RangeOverflow = true;
1477 if (SymType == SymbolRef::ST_Unknown || RangeOverflow) {
1478 // It is an external symbol (SymbolRef::ST_Unknown) or within a range
1479 // larger than 24-bits.
1480 StubMap::const_iterator i = Stubs.find(Value);
1481 if (i != Stubs.end()) {
1482 // Symbol function stub already created, just relocate to it
1483 resolveRelocation(Section, Offset,
1484 reinterpret_cast<uint64_t>(
1485 Section.getAddressWithOffset(i->second)),
1487 DEBUG(dbgs() << " Stub function found\n");
1489 // Create a new stub function.
1490 DEBUG(dbgs() << " Create a new stub function\n");
1491 Stubs[Value] = Section.getStubOffset();
1492 uint8_t *StubTargetAddr = createStubFunction(
1493 Section.getAddressWithOffset(Section.getStubOffset()),
1495 RelocationEntry RE(SectionID, StubTargetAddr - Section.getAddress(),
1496 ELF::R_PPC64_ADDR64, Value.Addend);
1498 // Generates the 64-bits address loads as exemplified in section
1499 // 4.5.1 in PPC64 ELF ABI. Note that the relocations need to
1500 // apply to the low part of the instructions, so we have to update
1501 // the offset according to the target endianness.
1502 uint64_t StubRelocOffset = StubTargetAddr - Section.getAddress();
1503 if (!IsTargetLittleEndian)
1504 StubRelocOffset += 2;
1506 RelocationEntry REhst(SectionID, StubRelocOffset + 0,
1507 ELF::R_PPC64_ADDR16_HIGHEST, Value.Addend);
1508 RelocationEntry REhr(SectionID, StubRelocOffset + 4,
1509 ELF::R_PPC64_ADDR16_HIGHER, Value.Addend);
1510 RelocationEntry REh(SectionID, StubRelocOffset + 12,
1511 ELF::R_PPC64_ADDR16_HI, Value.Addend);
1512 RelocationEntry REl(SectionID, StubRelocOffset + 16,
1513 ELF::R_PPC64_ADDR16_LO, Value.Addend);
1515 if (Value.SymbolName) {
1516 addRelocationForSymbol(REhst, Value.SymbolName);
1517 addRelocationForSymbol(REhr, Value.SymbolName);
1518 addRelocationForSymbol(REh, Value.SymbolName);
1519 addRelocationForSymbol(REl, Value.SymbolName);
1521 addRelocationForSection(REhst, Value.SectionID);
1522 addRelocationForSection(REhr, Value.SectionID);
1523 addRelocationForSection(REh, Value.SectionID);
1524 addRelocationForSection(REl, Value.SectionID);
1527 resolveRelocation(Section, Offset, reinterpret_cast<uint64_t>(
1528 Section.getAddressWithOffset(
1529 Section.getStubOffset())),
1531 Section.advanceStubOffset(getMaxStubSize());
1533 if (SymType == SymbolRef::ST_Unknown) {
1534 // Restore the TOC for external calls
1535 if (AbiVariant == 2)
1536 writeInt32BE(Target + 4, 0xE8410018); // ld r2,28(r1)
1538 writeInt32BE(Target + 4, 0xE8410028); // ld r2,40(r1)
1541 } else if (RelType == ELF::R_PPC64_TOC16 ||
1542 RelType == ELF::R_PPC64_TOC16_DS ||
1543 RelType == ELF::R_PPC64_TOC16_LO ||
1544 RelType == ELF::R_PPC64_TOC16_LO_DS ||
1545 RelType == ELF::R_PPC64_TOC16_HI ||
1546 RelType == ELF::R_PPC64_TOC16_HA) {
1547 // These relocations are supposed to subtract the TOC address from
1548 // the final value. This does not fit cleanly into the RuntimeDyld
1549 // scheme, since there may be *two* sections involved in determining
1550 // the relocation value (the section of the symbol referred to by the
1551 // relocation, and the TOC section associated with the current module).
1553 // Fortunately, these relocations are currently only ever generated
1554 // referring to symbols that themselves reside in the TOC, which means
1555 // that the two sections are actually the same. Thus they cancel out
1556 // and we can immediately resolve the relocation right now.
1558 case ELF::R_PPC64_TOC16: RelType = ELF::R_PPC64_ADDR16; break;
1559 case ELF::R_PPC64_TOC16_DS: RelType = ELF::R_PPC64_ADDR16_DS; break;
1560 case ELF::R_PPC64_TOC16_LO: RelType = ELF::R_PPC64_ADDR16_LO; break;
1561 case ELF::R_PPC64_TOC16_LO_DS: RelType = ELF::R_PPC64_ADDR16_LO_DS; break;
1562 case ELF::R_PPC64_TOC16_HI: RelType = ELF::R_PPC64_ADDR16_HI; break;
1563 case ELF::R_PPC64_TOC16_HA: RelType = ELF::R_PPC64_ADDR16_HA; break;
1564 default: llvm_unreachable("Wrong relocation type.");
1567 RelocationValueRef TOCValue;
1568 findPPC64TOCSection(Obj, ObjSectionToID, TOCValue);
1569 if (Value.SymbolName || Value.SectionID != TOCValue.SectionID)
1570 llvm_unreachable("Unsupported TOC relocation.");
1571 Value.Addend -= TOCValue.Addend;
1572 resolveRelocation(Sections[SectionID], Offset, Value.Addend, RelType, 0);
1574 // There are two ways to refer to the TOC address directly: either
1575 // via a ELF::R_PPC64_TOC relocation (where both symbol and addend are
1576 // ignored), or via any relocation that refers to the magic ".TOC."
1577 // symbols (in which case the addend is respected).
1578 if (RelType == ELF::R_PPC64_TOC) {
1579 RelType = ELF::R_PPC64_ADDR64;
1580 findPPC64TOCSection(Obj, ObjSectionToID, Value);
1581 } else if (TargetName == ".TOC.") {
1582 findPPC64TOCSection(Obj, ObjSectionToID, Value);
1583 Value.Addend += Addend;
1586 RelocationEntry RE(SectionID, Offset, RelType, Value.Addend);
1588 if (Value.SymbolName)
1589 addRelocationForSymbol(RE, Value.SymbolName);
1591 addRelocationForSection(RE, Value.SectionID);
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.
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 DEBUG(dbgs() << "\t\tThis is a SystemZ indirect relocation.");
1605 SectionEntry &Section = Sections[SectionID];
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 DEBUG(dbgs() << " Stub function found\n");
1614 // Create a new stub function.
1615 DEBUG(dbgs() << " Create a new stub function\n");
1617 uintptr_t BaseAddress = uintptr_t(Section.getAddress());
1618 uintptr_t StubAlignment = getStubAlignment();
1620 (BaseAddress + Section.getStubOffset() + StubAlignment - 1) &
1622 unsigned StubOffset = StubAddress - BaseAddress;
1624 Stubs[Value] = StubOffset;
1625 createStubFunction((uint8_t *)StubAddress);
1626 RelocationEntry RE(SectionID, StubOffset + 8, ELF::R_390_64,
1628 if (Value.SymbolName)
1629 addRelocationForSymbol(RE, Value.SymbolName);
1631 addRelocationForSection(RE, Value.SectionID);
1632 Section.advanceStubOffset(getMaxStubSize());
1635 if (RelType == ELF::R_390_GOTENT)
1636 resolveRelocation(Section, Offset, StubAddress + 8, ELF::R_390_PC32DBL,
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
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,
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.
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 DEBUG(dbgs() << " Stub function found\n");
1668 // Create a new stub function (equivalent to a PLT entry).
1669 DEBUG(dbgs() << " Create a new stub function\n");
1671 uintptr_t BaseAddress = uintptr_t(Section.getAddress());
1672 uintptr_t StubAlignment = getStubAlignment();
1674 (BaseAddress + Section.getStubOffset() + StubAlignment - 1) &
1676 unsigned StubOffset = StubAddress - BaseAddress;
1677 Stubs[Value] = StubOffset;
1678 createStubFunction((uint8_t *)StubAddress);
1680 // Bump our stub offset counter
1681 Section.advanceStubOffset(getMaxStubSize());
1683 // Allocate a GOT Entry
1684 uint64_t GOTOffset = allocateGOTEntries(SectionID, 1);
1686 // The load of the GOT address has an addend of -4
1687 resolveGOTOffsetRelocation(SectionID, StubOffset + 2, GOTOffset - 4);
1689 // Fill in the value of the symbol we're targeting into the GOT
1690 addRelocationForSymbol(
1691 computeGOTOffsetRE(SectionID, GOTOffset, 0, ELF::R_X86_64_64),
1695 // Make the target call a call into the stub table.
1696 resolveRelocation(Section, Offset, StubAddress, ELF::R_X86_64_PC32,
1699 RelocationEntry RE(SectionID, Offset, ELF::R_X86_64_PC32, Value.Addend,
1701 addRelocationForSection(RE, Value.SectionID);
1703 } else if (RelType == ELF::R_X86_64_GOTPCREL) {
1704 uint64_t GOTOffset = allocateGOTEntries(SectionID, 1);
1705 resolveGOTOffsetRelocation(SectionID, Offset, GOTOffset + Addend);
1707 // Fill in the value of the symbol we're targeting into the GOT
1708 RelocationEntry RE = computeGOTOffsetRE(SectionID, GOTOffset, Value.Offset, ELF::R_X86_64_64);
1709 if (Value.SymbolName)
1710 addRelocationForSymbol(RE, Value.SymbolName);
1712 addRelocationForSection(RE, Value.SectionID);
1713 } else if (RelType == ELF::R_X86_64_PC32) {
1714 Value.Addend += support::ulittle32_t::ref(computePlaceholderAddress(SectionID, Offset));
1715 processSimpleRelocation(SectionID, Offset, RelType, Value);
1716 } else if (RelType == ELF::R_X86_64_PC64) {
1717 Value.Addend += support::ulittle64_t::ref(computePlaceholderAddress(SectionID, Offset));
1718 processSimpleRelocation(SectionID, Offset, RelType, Value);
1720 processSimpleRelocation(SectionID, Offset, RelType, Value);
1723 if (Arch == Triple::x86) {
1724 Value.Addend += support::ulittle32_t::ref(computePlaceholderAddress(SectionID, Offset));
1726 processSimpleRelocation(SectionID, Offset, RelType, Value);
1731 size_t RuntimeDyldELF::getGOTEntrySize() {
1732 // We don't use the GOT in all of these cases, but it's essentially free
1733 // to put them all here.
1736 case Triple::x86_64:
1737 case Triple::aarch64:
1738 case Triple::aarch64_be:
1740 case Triple::ppc64le:
1741 case Triple::systemz:
1742 Result = sizeof(uint64_t);
1747 Result = sizeof(uint32_t);
1750 case Triple::mipsel:
1751 case Triple::mips64:
1752 case Triple::mips64el:
1754 Result = sizeof(uint32_t);
1755 else if (IsMipsN64ABI)
1756 Result = sizeof(uint64_t);
1758 llvm_unreachable("Mips ABI not handled");
1761 llvm_unreachable("Unsupported CPU type!");
1766 uint64_t RuntimeDyldELF::allocateGOTEntries(unsigned SectionID, unsigned no)
1768 (void)SectionID; // The GOT Section is the same for all section in the object file
1769 if (GOTSectionID == 0) {
1770 GOTSectionID = Sections.size();
1771 // Reserve a section id. We'll allocate the section later
1772 // once we know the total size
1773 Sections.push_back(SectionEntry(".got", nullptr, 0, 0));
1775 uint64_t StartOffset = CurrentGOTIndex * getGOTEntrySize();
1776 CurrentGOTIndex += no;
1780 void RuntimeDyldELF::resolveGOTOffsetRelocation(unsigned SectionID, uint64_t Offset, uint64_t GOTOffset)
1782 // Fill in the relative address of the GOT Entry into the stub
1783 RelocationEntry GOTRE(SectionID, Offset, ELF::R_X86_64_PC32, GOTOffset);
1784 addRelocationForSection(GOTRE, GOTSectionID);
1787 RelocationEntry RuntimeDyldELF::computeGOTOffsetRE(unsigned SectionID, uint64_t GOTOffset, uint64_t SymbolOffset,
1790 (void)SectionID; // The GOT Section is the same for all section in the object file
1791 return RelocationEntry(GOTSectionID, GOTOffset, Type, SymbolOffset);
1794 void RuntimeDyldELF::finalizeLoad(const ObjectFile &Obj,
1795 ObjSectionToIDMap &SectionMap) {
1797 if (!PendingRelocs.empty())
1798 report_fatal_error("Can't find matching LO16 reloc");
1800 // If necessary, allocate the global offset table
1801 if (GOTSectionID != 0) {
1802 // Allocate memory for the section
1803 size_t TotalSize = CurrentGOTIndex * getGOTEntrySize();
1804 uint8_t *Addr = MemMgr.allocateDataSection(TotalSize, getGOTEntrySize(),
1805 GOTSectionID, ".got", false);
1807 report_fatal_error("Unable to allocate memory for GOT!");
1809 Sections[GOTSectionID] = SectionEntry(".got", Addr, TotalSize, 0);
1812 Checker->registerSection(Obj.getFileName(), GOTSectionID);
1814 // For now, initialize all GOT entries to zero. We'll fill them in as
1815 // needed when GOT-based relocations are applied.
1816 memset(Addr, 0, TotalSize);
1818 // To correctly resolve Mips GOT relocations, we need a mapping from
1819 // object's sections to GOTs.
1820 for (section_iterator SI = Obj.section_begin(), SE = Obj.section_end();
1822 if (SI->relocation_begin() != SI->relocation_end()) {
1823 section_iterator RelocatedSection = SI->getRelocatedSection();
1824 ObjSectionToIDMap::iterator i = SectionMap.find(*RelocatedSection);
1825 assert (i != SectionMap.end());
1826 SectionToGOTMap[i->second] = GOTSectionID;
1829 GOTSymbolOffsets.clear();
1833 // Look for and record the EH frame section.
1834 ObjSectionToIDMap::iterator i, e;
1835 for (i = SectionMap.begin(), e = SectionMap.end(); i != e; ++i) {
1836 const SectionRef &Section = i->first;
1838 Section.getName(Name);
1839 if (Name == ".eh_frame") {
1840 UnregisteredEHFrameSections.push_back(i->second);
1846 CurrentGOTIndex = 0;
1849 bool RuntimeDyldELF::isCompatibleFile(const object::ObjectFile &Obj) const {