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();
74 // The MemoryBuffer passed into this constructor is just a wrapper around the
75 // actual memory. Ultimately, the Binary parent class will take ownership of
76 // this MemoryBuffer object but not the underlying memory.
78 DyldELFObject<ELFT>::DyldELFObject(MemoryBufferRef Wrapper, std::error_code &EC)
79 : ELFObjectFile<ELFT>(Wrapper, EC) {
80 this->isDyldELFObject = true;
84 void DyldELFObject<ELFT>::updateSectionAddress(const SectionRef &Sec,
86 DataRefImpl ShdrRef = Sec.getRawDataRefImpl();
88 const_cast<Elf_Shdr *>(reinterpret_cast<const Elf_Shdr *>(ShdrRef.p));
90 // This assumes the address passed in matches the target address bitness
91 // The template-based type cast handles everything else.
92 shdr->sh_addr = static_cast<addr_type>(Addr);
96 void DyldELFObject<ELFT>::updateSymbolAddress(const SymbolRef &SymRef,
99 Elf_Sym *sym = const_cast<Elf_Sym *>(
100 ELFObjectFile<ELFT>::getSymbol(SymRef.getRawDataRefImpl()));
102 // This assumes the address passed in matches the target address bitness
103 // The template-based type cast handles everything else.
104 sym->st_value = static_cast<addr_type>(Addr);
107 class LoadedELFObjectInfo
108 : public RuntimeDyld::LoadedObjectInfoHelper<LoadedELFObjectInfo> {
110 LoadedELFObjectInfo(RuntimeDyldImpl &RTDyld, unsigned BeginIdx,
112 : LoadedObjectInfoHelper(RTDyld, BeginIdx, EndIdx) {}
114 OwningBinary<ObjectFile>
115 getObjectForDebug(const ObjectFile &Obj) const override;
118 template <typename ELFT>
119 std::unique_ptr<DyldELFObject<ELFT>>
120 createRTDyldELFObject(MemoryBufferRef Buffer,
121 const LoadedELFObjectInfo &L,
122 std::error_code &ec) {
123 typedef typename ELFFile<ELFT>::Elf_Shdr Elf_Shdr;
124 typedef typename ELFDataTypeTypedefHelper<ELFT>::value_type addr_type;
126 std::unique_ptr<DyldELFObject<ELFT>> Obj =
127 llvm::make_unique<DyldELFObject<ELFT>>(Buffer, ec);
129 // Iterate over all sections in the object.
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(SectionName)) {
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);
149 OwningBinary<ObjectFile> createELFDebugObject(const ObjectFile &Obj,
150 const LoadedELFObjectInfo &L) {
151 assert(Obj.isELF() && "Not an ELF object file.");
153 std::unique_ptr<MemoryBuffer> Buffer =
154 MemoryBuffer::getMemBufferCopy(Obj.getData(), Obj.getFileName());
158 std::unique_ptr<ObjectFile> DebugObj;
159 if (Obj.getBytesInAddress() == 4 && Obj.isLittleEndian()) {
160 typedef ELFType<support::little, false> ELF32LE;
161 DebugObj = createRTDyldELFObject<ELF32LE>(Buffer->getMemBufferRef(), L, ec);
162 } else if (Obj.getBytesInAddress() == 4 && !Obj.isLittleEndian()) {
163 typedef ELFType<support::big, false> ELF32BE;
164 DebugObj = createRTDyldELFObject<ELF32BE>(Buffer->getMemBufferRef(), L, ec);
165 } else if (Obj.getBytesInAddress() == 8 && !Obj.isLittleEndian()) {
166 typedef ELFType<support::big, true> ELF64BE;
167 DebugObj = createRTDyldELFObject<ELF64BE>(Buffer->getMemBufferRef(), L, ec);
168 } else if (Obj.getBytesInAddress() == 8 && Obj.isLittleEndian()) {
169 typedef ELFType<support::little, true> ELF64LE;
170 DebugObj = createRTDyldELFObject<ELF64LE>(Buffer->getMemBufferRef(), L, ec);
172 llvm_unreachable("Unexpected ELF format");
174 assert(!ec && "Could not construct copy ELF object file");
176 return OwningBinary<ObjectFile>(std::move(DebugObj), std::move(Buffer));
179 OwningBinary<ObjectFile>
180 LoadedELFObjectInfo::getObjectForDebug(const ObjectFile &Obj) const {
181 return createELFDebugObject(Obj, *this);
188 RuntimeDyldELF::RuntimeDyldELF(RuntimeDyld::MemoryManager &MemMgr,
189 RuntimeDyld::SymbolResolver &Resolver)
190 : RuntimeDyldImpl(MemMgr, Resolver), GOTSectionID(0), CurrentGOTIndex(0) {}
191 RuntimeDyldELF::~RuntimeDyldELF() {}
193 void RuntimeDyldELF::registerEHFrames() {
194 for (int i = 0, e = UnregisteredEHFrameSections.size(); i != e; ++i) {
195 SID EHFrameSID = UnregisteredEHFrameSections[i];
196 uint8_t *EHFrameAddr = Sections[EHFrameSID].Address;
197 uint64_t EHFrameLoadAddr = Sections[EHFrameSID].LoadAddress;
198 size_t EHFrameSize = Sections[EHFrameSID].Size;
199 MemMgr.registerEHFrames(EHFrameAddr, EHFrameLoadAddr, EHFrameSize);
200 RegisteredEHFrameSections.push_back(EHFrameSID);
202 UnregisteredEHFrameSections.clear();
205 void RuntimeDyldELF::deregisterEHFrames() {
206 for (int i = 0, e = RegisteredEHFrameSections.size(); i != e; ++i) {
207 SID EHFrameSID = RegisteredEHFrameSections[i];
208 uint8_t *EHFrameAddr = Sections[EHFrameSID].Address;
209 uint64_t EHFrameLoadAddr = Sections[EHFrameSID].LoadAddress;
210 size_t EHFrameSize = Sections[EHFrameSID].Size;
211 MemMgr.deregisterEHFrames(EHFrameAddr, EHFrameLoadAddr, EHFrameSize);
213 RegisteredEHFrameSections.clear();
216 std::unique_ptr<RuntimeDyld::LoadedObjectInfo>
217 RuntimeDyldELF::loadObject(const object::ObjectFile &O) {
218 unsigned SectionStartIdx, SectionEndIdx;
219 std::tie(SectionStartIdx, SectionEndIdx) = loadObjectImpl(O);
220 return llvm::make_unique<LoadedELFObjectInfo>(*this, SectionStartIdx,
224 void RuntimeDyldELF::resolveX86_64Relocation(const SectionEntry &Section,
225 uint64_t Offset, uint64_t Value,
226 uint32_t Type, int64_t Addend,
227 uint64_t SymOffset) {
230 llvm_unreachable("Relocation type not implemented yet!");
232 case ELF::R_X86_64_64: {
233 support::ulittle64_t::ref(Section.Address + Offset) = Value + Addend;
234 DEBUG(dbgs() << "Writing " << format("%p", (Value + Addend)) << " at "
235 << format("%p\n", Section.Address + Offset));
238 case ELF::R_X86_64_32:
239 case ELF::R_X86_64_32S: {
241 assert((Type == ELF::R_X86_64_32 && (Value <= UINT32_MAX)) ||
242 (Type == ELF::R_X86_64_32S &&
243 ((int64_t)Value <= INT32_MAX && (int64_t)Value >= INT32_MIN)));
244 uint32_t TruncatedAddr = (Value & 0xFFFFFFFF);
245 support::ulittle32_t::ref(Section.Address + Offset) = TruncatedAddr;
246 DEBUG(dbgs() << "Writing " << format("%p", TruncatedAddr) << " at "
247 << format("%p\n", Section.Address + Offset));
250 case ELF::R_X86_64_PC32: {
251 uint64_t FinalAddress = Section.LoadAddress + Offset;
252 int64_t RealOffset = Value + Addend - FinalAddress;
253 assert(isInt<32>(RealOffset));
254 int32_t TruncOffset = (RealOffset & 0xFFFFFFFF);
255 support::ulittle32_t::ref(Section.Address + Offset) = TruncOffset;
258 case ELF::R_X86_64_PC64: {
259 uint64_t FinalAddress = Section.LoadAddress + Offset;
260 int64_t RealOffset = Value + Addend - FinalAddress;
261 support::ulittle64_t::ref(Section.Address + Offset) = RealOffset;
267 void RuntimeDyldELF::resolveX86Relocation(const SectionEntry &Section,
268 uint64_t Offset, uint32_t Value,
269 uint32_t Type, int32_t Addend) {
271 case ELF::R_386_32: {
272 support::ulittle32_t::ref(Section.Address + Offset) = Value + Addend;
275 case ELF::R_386_PC32: {
276 uint32_t FinalAddress = ((Section.LoadAddress + Offset) & 0xFFFFFFFF);
277 uint32_t RealOffset = Value + Addend - FinalAddress;
278 support::ulittle32_t::ref(Section.Address + Offset) = RealOffset;
282 // There are other relocation types, but it appears these are the
283 // only ones currently used by the LLVM ELF object writer
284 llvm_unreachable("Relocation type not implemented yet!");
289 void RuntimeDyldELF::resolveAArch64Relocation(const SectionEntry &Section,
290 uint64_t Offset, uint64_t Value,
291 uint32_t Type, int64_t Addend) {
292 uint32_t *TargetPtr = reinterpret_cast<uint32_t *>(Section.Address + Offset);
293 uint64_t FinalAddress = Section.LoadAddress + Offset;
295 DEBUG(dbgs() << "resolveAArch64Relocation, LocalAddress: 0x"
296 << format("%llx", Section.Address + Offset)
297 << " FinalAddress: 0x" << format("%llx", FinalAddress)
298 << " Value: 0x" << format("%llx", Value) << " Type: 0x"
299 << format("%x", Type) << " Addend: 0x" << format("%llx", Addend)
304 llvm_unreachable("Relocation type not implemented yet!");
306 case ELF::R_AARCH64_ABS64: {
307 uint64_t *TargetPtr =
308 reinterpret_cast<uint64_t *>(Section.Address + Offset);
309 *TargetPtr = Value + Addend;
312 case ELF::R_AARCH64_PREL32: {
313 uint64_t Result = Value + Addend - FinalAddress;
314 assert(static_cast<int64_t>(Result) >= INT32_MIN &&
315 static_cast<int64_t>(Result) <= UINT32_MAX);
316 *TargetPtr = static_cast<uint32_t>(Result & 0xffffffffU);
319 case ELF::R_AARCH64_CALL26: // fallthrough
320 case ELF::R_AARCH64_JUMP26: {
321 // Operation: S+A-P. Set Call or B immediate value to bits fff_fffc of the
323 uint64_t BranchImm = Value + Addend - FinalAddress;
325 // "Check that -2^27 <= result < 2^27".
326 assert(isInt<28>(BranchImm));
328 // AArch64 code is emitted with .rela relocations. The data already in any
329 // bits affected by the relocation on entry is garbage.
330 *TargetPtr &= 0xfc000000U;
331 // Immediate goes in bits 25:0 of B and BL.
332 *TargetPtr |= static_cast<uint32_t>(BranchImm & 0xffffffcU) >> 2;
335 case ELF::R_AARCH64_MOVW_UABS_G3: {
336 uint64_t Result = Value + Addend;
338 // AArch64 code is emitted with .rela relocations. The data already in any
339 // bits affected by the relocation on entry is garbage.
340 *TargetPtr &= 0xffe0001fU;
341 // Immediate goes in bits 20:5 of MOVZ/MOVK instruction
342 *TargetPtr |= Result >> (48 - 5);
343 // Shift must be "lsl #48", in bits 22:21
344 assert((*TargetPtr >> 21 & 0x3) == 3 && "invalid shift for relocation");
347 case ELF::R_AARCH64_MOVW_UABS_G2_NC: {
348 uint64_t Result = Value + Addend;
350 // AArch64 code is emitted with .rela relocations. The data already in any
351 // bits affected by the relocation on entry is garbage.
352 *TargetPtr &= 0xffe0001fU;
353 // Immediate goes in bits 20:5 of MOVZ/MOVK instruction
354 *TargetPtr |= ((Result & 0xffff00000000ULL) >> (32 - 5));
355 // Shift must be "lsl #32", in bits 22:21
356 assert((*TargetPtr >> 21 & 0x3) == 2 && "invalid shift for relocation");
359 case ELF::R_AARCH64_MOVW_UABS_G1_NC: {
360 uint64_t Result = Value + Addend;
362 // AArch64 code is emitted with .rela relocations. The data already in any
363 // bits affected by the relocation on entry is garbage.
364 *TargetPtr &= 0xffe0001fU;
365 // Immediate goes in bits 20:5 of MOVZ/MOVK instruction
366 *TargetPtr |= ((Result & 0xffff0000U) >> (16 - 5));
367 // Shift must be "lsl #16", in bits 22:2
368 assert((*TargetPtr >> 21 & 0x3) == 1 && "invalid shift for relocation");
371 case ELF::R_AARCH64_MOVW_UABS_G0_NC: {
372 uint64_t Result = Value + Addend;
374 // AArch64 code is emitted with .rela relocations. The data already in any
375 // bits affected by the relocation on entry is garbage.
376 *TargetPtr &= 0xffe0001fU;
377 // Immediate goes in bits 20:5 of MOVZ/MOVK instruction
378 *TargetPtr |= ((Result & 0xffffU) << 5);
379 // Shift must be "lsl #0", in bits 22:21.
380 assert((*TargetPtr >> 21 & 0x3) == 0 && "invalid shift for relocation");
383 case ELF::R_AARCH64_ADR_PREL_PG_HI21: {
384 // Operation: Page(S+A) - Page(P)
386 ((Value + Addend) & ~0xfffULL) - (FinalAddress & ~0xfffULL);
388 // Check that -2^32 <= X < 2^32
389 assert(isInt<33>(Result) && "overflow check failed for relocation");
391 // AArch64 code is emitted with .rela relocations. The data already in any
392 // bits affected by the relocation on entry is garbage.
393 *TargetPtr &= 0x9f00001fU;
394 // Immediate goes in bits 30:29 + 5:23 of ADRP instruction, taken
395 // from bits 32:12 of X.
396 *TargetPtr |= ((Result & 0x3000U) << (29 - 12));
397 *TargetPtr |= ((Result & 0x1ffffc000ULL) >> (14 - 5));
400 case ELF::R_AARCH64_LDST32_ABS_LO12_NC: {
402 uint64_t Result = Value + Addend;
404 // AArch64 code is emitted with .rela relocations. The data already in any
405 // bits affected by the relocation on entry is garbage.
406 *TargetPtr &= 0xffc003ffU;
407 // Immediate goes in bits 21:10 of LD/ST instruction, taken
408 // from bits 11:2 of X
409 *TargetPtr |= ((Result & 0xffc) << (10 - 2));
412 case ELF::R_AARCH64_LDST64_ABS_LO12_NC: {
414 uint64_t Result = Value + Addend;
416 // AArch64 code is emitted with .rela relocations. The data already in any
417 // bits affected by the relocation on entry is garbage.
418 *TargetPtr &= 0xffc003ffU;
419 // Immediate goes in bits 21:10 of LD/ST instruction, taken
420 // from bits 11:3 of X
421 *TargetPtr |= ((Result & 0xff8) << (10 - 3));
427 void RuntimeDyldELF::resolveARMRelocation(const SectionEntry &Section,
428 uint64_t Offset, uint32_t Value,
429 uint32_t Type, int32_t Addend) {
430 // TODO: Add Thumb relocations.
431 uint32_t *TargetPtr = (uint32_t *)(Section.Address + Offset);
432 uint32_t FinalAddress = ((Section.LoadAddress + Offset) & 0xFFFFFFFF);
435 DEBUG(dbgs() << "resolveARMRelocation, LocalAddress: "
436 << Section.Address + Offset
437 << " FinalAddress: " << format("%p", FinalAddress) << " Value: "
438 << format("%x", Value) << " Type: " << format("%x", Type)
439 << " Addend: " << format("%x", Addend) << "\n");
443 llvm_unreachable("Not implemented relocation type!");
445 case ELF::R_ARM_NONE:
447 case ELF::R_ARM_PREL31:
448 case ELF::R_ARM_TARGET1:
449 case ELF::R_ARM_ABS32:
452 // Write first 16 bit of 32 bit value to the mov instruction.
453 // Last 4 bit should be shifted.
454 case ELF::R_ARM_MOVW_ABS_NC:
455 case ELF::R_ARM_MOVT_ABS:
456 if (Type == ELF::R_ARM_MOVW_ABS_NC)
457 Value = Value & 0xFFFF;
458 else if (Type == ELF::R_ARM_MOVT_ABS)
459 Value = (Value >> 16) & 0xFFFF;
460 *TargetPtr &= ~0x000F0FFF;
461 *TargetPtr |= Value & 0xFFF;
462 *TargetPtr |= ((Value >> 12) & 0xF) << 16;
464 // Write 24 bit relative value to the branch instruction.
465 case ELF::R_ARM_PC24: // Fall through.
466 case ELF::R_ARM_CALL: // Fall through.
467 case ELF::R_ARM_JUMP24:
468 int32_t RelValue = static_cast<int32_t>(Value - FinalAddress - 8);
469 RelValue = (RelValue & 0x03FFFFFC) >> 2;
470 assert((*TargetPtr & 0xFFFFFF) == 0xFFFFFE);
471 *TargetPtr &= 0xFF000000;
472 *TargetPtr |= RelValue;
477 void RuntimeDyldELF::resolveMIPSRelocation(const SectionEntry &Section,
478 uint64_t Offset, uint32_t Value,
479 uint32_t Type, int32_t Addend) {
480 uint8_t *TargetPtr = Section.Address + Offset;
483 DEBUG(dbgs() << "resolveMIPSRelocation, LocalAddress: "
484 << Section.Address + Offset << " FinalAddress: "
485 << format("%p", Section.LoadAddress + Offset) << " Value: "
486 << format("%x", Value) << " Type: " << format("%x", Type)
487 << " Addend: " << format("%x", Addend) << "\n");
489 uint32_t Insn = readBytesUnaligned(TargetPtr, 4);
493 llvm_unreachable("Not implemented relocation type!");
496 writeBytesUnaligned(Value, TargetPtr, 4);
500 Insn |= (Value & 0x0fffffff) >> 2;
501 writeBytesUnaligned(Insn, TargetPtr, 4);
503 case ELF::R_MIPS_HI16:
504 // Get the higher 16-bits. Also add 1 if bit 15 is 1.
506 Insn |= ((Value + 0x8000) >> 16) & 0xffff;
507 writeBytesUnaligned(Insn, TargetPtr, 4);
509 case ELF::R_MIPS_LO16:
511 Insn |= Value & 0xffff;
512 writeBytesUnaligned(Insn, TargetPtr, 4);
514 case ELF::R_MIPS_PC32:
515 uint32_t FinalAddress = (Section.LoadAddress + Offset);
516 writeBytesUnaligned(Value + Addend - FinalAddress, (uint8_t *)TargetPtr, 4);
521 void RuntimeDyldELF::setMipsABI(const ObjectFile &Obj) {
522 if (!StringRef(Triple::getArchTypePrefix(Arch)).equals("mips")) {
523 IsMipsO32ABI = false;
524 IsMipsN64ABI = false;
528 Obj.getPlatformFlags(AbiVariant);
529 IsMipsO32ABI = AbiVariant & ELF::EF_MIPS_ABI_O32;
530 IsMipsN64ABI = Obj.getFileFormatName().equals("ELF64-mips");
531 if (AbiVariant & ELF::EF_MIPS_ABI2)
532 llvm_unreachable("Mips N32 ABI is not supported yet");
535 void RuntimeDyldELF::resolveMIPS64Relocation(const SectionEntry &Section,
536 uint64_t Offset, uint64_t Value,
537 uint32_t Type, int64_t Addend,
540 uint32_t r_type = Type & 0xff;
541 uint32_t r_type2 = (Type >> 8) & 0xff;
542 uint32_t r_type3 = (Type >> 16) & 0xff;
544 // RelType is used to keep information for which relocation type we are
545 // applying relocation.
546 uint32_t RelType = r_type;
547 int64_t CalculatedValue = evaluateMIPS64Relocation(Section, Offset, Value,
549 SymOffset, SectionID);
550 if (r_type2 != ELF::R_MIPS_NONE) {
552 CalculatedValue = evaluateMIPS64Relocation(Section, Offset, 0, RelType,
553 CalculatedValue, SymOffset,
556 if (r_type3 != ELF::R_MIPS_NONE) {
558 CalculatedValue = evaluateMIPS64Relocation(Section, Offset, 0, RelType,
559 CalculatedValue, SymOffset,
562 applyMIPS64Relocation(Section.Address + Offset, CalculatedValue, RelType);
566 RuntimeDyldELF::evaluateMIPS64Relocation(const SectionEntry &Section,
567 uint64_t Offset, uint64_t Value,
568 uint32_t Type, int64_t Addend,
569 uint64_t SymOffset, SID SectionID) {
571 DEBUG(dbgs() << "evaluateMIPS64Relocation, LocalAddress: 0x"
572 << format("%llx", Section.Address + Offset)
573 << " FinalAddress: 0x"
574 << format("%llx", Section.LoadAddress + Offset)
575 << " Value: 0x" << format("%llx", Value) << " Type: 0x"
576 << format("%x", Type) << " Addend: 0x" << format("%llx", Addend)
577 << " SymOffset: " << format("%x", SymOffset)
582 llvm_unreachable("Not implemented relocation type!");
584 case ELF::R_MIPS_JALR:
585 case ELF::R_MIPS_NONE:
589 return Value + Addend;
591 return ((Value + Addend) >> 2) & 0x3ffffff;
592 case ELF::R_MIPS_GPREL16: {
593 uint64_t GOTAddr = getSectionLoadAddress(SectionToGOTMap[SectionID]);
594 return Value + Addend - (GOTAddr + 0x7ff0);
596 case ELF::R_MIPS_SUB:
597 return Value - Addend;
598 case ELF::R_MIPS_HI16:
599 // Get the higher 16-bits. Also add 1 if bit 15 is 1.
600 return ((Value + Addend + 0x8000) >> 16) & 0xffff;
601 case ELF::R_MIPS_LO16:
602 return (Value + Addend) & 0xffff;
603 case ELF::R_MIPS_CALL16:
604 case ELF::R_MIPS_GOT_DISP:
605 case ELF::R_MIPS_GOT_PAGE: {
606 uint8_t *LocalGOTAddr =
607 getSectionAddress(SectionToGOTMap[SectionID]) + SymOffset;
608 uint64_t GOTEntry = readBytesUnaligned(LocalGOTAddr, 8);
611 if (Type == ELF::R_MIPS_GOT_PAGE)
612 Value = (Value + 0x8000) & ~0xffff;
615 assert(GOTEntry == Value &&
616 "GOT entry has two different addresses.");
618 writeBytesUnaligned(Value, LocalGOTAddr, 8);
620 return (SymOffset - 0x7ff0) & 0xffff;
622 case ELF::R_MIPS_GOT_OFST: {
623 int64_t page = (Value + Addend + 0x8000) & ~0xffff;
624 return (Value + Addend - page) & 0xffff;
626 case ELF::R_MIPS_GPREL32: {
627 uint64_t GOTAddr = getSectionLoadAddress(SectionToGOTMap[SectionID]);
628 return Value + Addend - (GOTAddr + 0x7ff0);
630 case ELF::R_MIPS_PC16: {
631 uint64_t FinalAddress = (Section.LoadAddress + Offset);
632 return ((Value + Addend - FinalAddress - 4) >> 2) & 0xffff;
634 case ELF::R_MIPS_PC18_S3: {
635 uint64_t FinalAddress = (Section.LoadAddress + Offset);
636 return ((Value + Addend - ((FinalAddress | 7) ^ 7)) >> 3) & 0x3ffff;
638 case ELF::R_MIPS_PC19_S2: {
639 uint64_t FinalAddress = (Section.LoadAddress + Offset);
640 return ((Value + Addend - FinalAddress) >> 2) & 0x7ffff;
642 case ELF::R_MIPS_PC21_S2: {
643 uint64_t FinalAddress = (Section.LoadAddress + Offset);
644 return ((Value + Addend - FinalAddress) >> 2) & 0x1fffff;
646 case ELF::R_MIPS_PC26_S2: {
647 uint64_t FinalAddress = (Section.LoadAddress + Offset);
648 return ((Value + Addend - FinalAddress) >> 2) & 0x3ffffff;
650 case ELF::R_MIPS_PCHI16: {
651 uint64_t FinalAddress = (Section.LoadAddress + Offset);
652 return ((Value + Addend - FinalAddress + 0x8000) >> 16) & 0xffff;
654 case ELF::R_MIPS_PCLO16: {
655 uint64_t FinalAddress = (Section.LoadAddress + Offset);
656 return (Value + Addend - FinalAddress) & 0xffff;
662 void RuntimeDyldELF::applyMIPS64Relocation(uint8_t *TargetPtr,
663 int64_t CalculatedValue,
665 uint32_t Insn = readBytesUnaligned(TargetPtr, 4);
671 case ELF::R_MIPS_GPREL32:
672 writeBytesUnaligned(CalculatedValue & 0xffffffff, TargetPtr, 4);
675 case ELF::R_MIPS_SUB:
676 writeBytesUnaligned(CalculatedValue, TargetPtr, 8);
679 case ELF::R_MIPS_PC26_S2:
680 Insn = (Insn & 0xfc000000) | CalculatedValue;
681 writeBytesUnaligned(Insn, TargetPtr, 4);
683 case ELF::R_MIPS_GPREL16:
684 Insn = (Insn & 0xffff0000) | (CalculatedValue & 0xffff);
685 writeBytesUnaligned(Insn, TargetPtr, 4);
687 case ELF::R_MIPS_HI16:
688 case ELF::R_MIPS_LO16:
689 case ELF::R_MIPS_PCHI16:
690 case ELF::R_MIPS_PCLO16:
691 case ELF::R_MIPS_PC16:
692 case ELF::R_MIPS_CALL16:
693 case ELF::R_MIPS_GOT_DISP:
694 case ELF::R_MIPS_GOT_PAGE:
695 case ELF::R_MIPS_GOT_OFST:
696 Insn = (Insn & 0xffff0000) | CalculatedValue;
697 writeBytesUnaligned(Insn, TargetPtr, 4);
699 case ELF::R_MIPS_PC18_S3:
700 Insn = (Insn & 0xfffc0000) | CalculatedValue;
701 writeBytesUnaligned(Insn, TargetPtr, 4);
703 case ELF::R_MIPS_PC19_S2:
704 Insn = (Insn & 0xfff80000) | CalculatedValue;
705 writeBytesUnaligned(Insn, TargetPtr, 4);
707 case ELF::R_MIPS_PC21_S2:
708 Insn = (Insn & 0xffe00000) | CalculatedValue;
709 writeBytesUnaligned(Insn, TargetPtr, 4);
714 // Return the .TOC. section and offset.
715 void RuntimeDyldELF::findPPC64TOCSection(const ObjectFile &Obj,
716 ObjSectionToIDMap &LocalSections,
717 RelocationValueRef &Rel) {
718 // Set a default SectionID in case we do not find a TOC section below.
719 // This may happen for references to TOC base base (sym@toc, .odp
720 // relocation) without a .toc directive. In this case just use the
721 // first section (which is usually the .odp) since the code won't
722 // reference the .toc base directly.
723 Rel.SymbolName = NULL;
726 // The TOC consists of sections .got, .toc, .tocbss, .plt in that
727 // order. The TOC starts where the first of these sections starts.
728 for (auto &Section: Obj.sections()) {
729 StringRef SectionName;
730 check(Section.getName(SectionName));
732 if (SectionName == ".got"
733 || SectionName == ".toc"
734 || SectionName == ".tocbss"
735 || SectionName == ".plt") {
736 Rel.SectionID = findOrEmitSection(Obj, Section, false, LocalSections);
741 // Per the ppc64-elf-linux ABI, The TOC base is TOC value plus 0x8000
742 // thus permitting a full 64 Kbytes segment.
746 // Returns the sections and offset associated with the ODP entry referenced
748 void RuntimeDyldELF::findOPDEntrySection(const ObjectFile &Obj,
749 ObjSectionToIDMap &LocalSections,
750 RelocationValueRef &Rel) {
751 // Get the ELF symbol value (st_value) to compare with Relocation offset in
753 for (section_iterator si = Obj.section_begin(), se = Obj.section_end();
755 section_iterator RelSecI = si->getRelocatedSection();
756 if (RelSecI == Obj.section_end())
759 StringRef RelSectionName;
760 check(RelSecI->getName(RelSectionName));
761 if (RelSectionName != ".opd")
764 for (relocation_iterator i = si->relocation_begin(),
765 e = si->relocation_end();
767 // The R_PPC64_ADDR64 relocation indicates the first field
770 check(i->getType(TypeFunc));
771 if (TypeFunc != ELF::R_PPC64_ADDR64) {
776 uint64_t TargetSymbolOffset;
777 symbol_iterator TargetSymbol = i->getSymbol();
778 check(i->getOffset(TargetSymbolOffset));
780 check(getELFRelocationAddend(*i, Addend));
786 // Just check if following relocation is a R_PPC64_TOC
788 check(i->getType(TypeTOC));
789 if (TypeTOC != ELF::R_PPC64_TOC)
792 // Finally compares the Symbol value and the target symbol offset
793 // to check if this .opd entry refers to the symbol the relocation
795 if (Rel.Addend != (int64_t)TargetSymbolOffset)
798 section_iterator tsi(Obj.section_end());
799 check(TargetSymbol->getSection(tsi));
800 bool IsCode = tsi->isText();
801 Rel.SectionID = findOrEmitSection(Obj, (*tsi), IsCode, LocalSections);
802 Rel.Addend = (intptr_t)Addend;
806 llvm_unreachable("Attempting to get address of ODP entry!");
809 // Relocation masks following the #lo(value), #hi(value), #ha(value),
810 // #higher(value), #highera(value), #highest(value), and #highesta(value)
811 // macros defined in section 4.5.1. Relocation Types of the PPC-elf64abi
814 static inline uint16_t applyPPClo(uint64_t value) { return value & 0xffff; }
816 static inline uint16_t applyPPChi(uint64_t value) {
817 return (value >> 16) & 0xffff;
820 static inline uint16_t applyPPCha (uint64_t value) {
821 return ((value + 0x8000) >> 16) & 0xffff;
824 static inline uint16_t applyPPChigher(uint64_t value) {
825 return (value >> 32) & 0xffff;
828 static inline uint16_t applyPPChighera (uint64_t value) {
829 return ((value + 0x8000) >> 32) & 0xffff;
832 static inline uint16_t applyPPChighest(uint64_t value) {
833 return (value >> 48) & 0xffff;
836 static inline uint16_t applyPPChighesta (uint64_t value) {
837 return ((value + 0x8000) >> 48) & 0xffff;
840 void RuntimeDyldELF::resolvePPC64Relocation(const SectionEntry &Section,
841 uint64_t Offset, uint64_t Value,
842 uint32_t Type, int64_t Addend) {
843 uint8_t *LocalAddress = Section.Address + Offset;
846 llvm_unreachable("Relocation type not implemented yet!");
848 case ELF::R_PPC64_ADDR16:
849 writeInt16BE(LocalAddress, applyPPClo(Value + Addend));
851 case ELF::R_PPC64_ADDR16_DS:
852 writeInt16BE(LocalAddress, applyPPClo(Value + Addend) & ~3);
854 case ELF::R_PPC64_ADDR16_LO:
855 writeInt16BE(LocalAddress, applyPPClo(Value + Addend));
857 case ELF::R_PPC64_ADDR16_LO_DS:
858 writeInt16BE(LocalAddress, applyPPClo(Value + Addend) & ~3);
860 case ELF::R_PPC64_ADDR16_HI:
861 writeInt16BE(LocalAddress, applyPPChi(Value + Addend));
863 case ELF::R_PPC64_ADDR16_HA:
864 writeInt16BE(LocalAddress, applyPPCha(Value + Addend));
866 case ELF::R_PPC64_ADDR16_HIGHER:
867 writeInt16BE(LocalAddress, applyPPChigher(Value + Addend));
869 case ELF::R_PPC64_ADDR16_HIGHERA:
870 writeInt16BE(LocalAddress, applyPPChighera(Value + Addend));
872 case ELF::R_PPC64_ADDR16_HIGHEST:
873 writeInt16BE(LocalAddress, applyPPChighest(Value + Addend));
875 case ELF::R_PPC64_ADDR16_HIGHESTA:
876 writeInt16BE(LocalAddress, applyPPChighesta(Value + Addend));
878 case ELF::R_PPC64_ADDR14: {
879 assert(((Value + Addend) & 3) == 0);
880 // Preserve the AA/LK bits in the branch instruction
881 uint8_t aalk = *(LocalAddress + 3);
882 writeInt16BE(LocalAddress + 2, (aalk & 3) | ((Value + Addend) & 0xfffc));
884 case ELF::R_PPC64_REL16_LO: {
885 uint64_t FinalAddress = (Section.LoadAddress + Offset);
886 uint64_t Delta = Value - FinalAddress + Addend;
887 writeInt16BE(LocalAddress, applyPPClo(Delta));
889 case ELF::R_PPC64_REL16_HI: {
890 uint64_t FinalAddress = (Section.LoadAddress + Offset);
891 uint64_t Delta = Value - FinalAddress + Addend;
892 writeInt16BE(LocalAddress, applyPPChi(Delta));
894 case ELF::R_PPC64_REL16_HA: {
895 uint64_t FinalAddress = (Section.LoadAddress + Offset);
896 uint64_t Delta = Value - FinalAddress + Addend;
897 writeInt16BE(LocalAddress, applyPPCha(Delta));
899 case ELF::R_PPC64_ADDR32: {
900 int32_t Result = static_cast<int32_t>(Value + Addend);
901 if (SignExtend32<32>(Result) != Result)
902 llvm_unreachable("Relocation R_PPC64_ADDR32 overflow");
903 writeInt32BE(LocalAddress, Result);
905 case ELF::R_PPC64_REL24: {
906 uint64_t FinalAddress = (Section.LoadAddress + Offset);
907 int32_t delta = static_cast<int32_t>(Value - FinalAddress + Addend);
908 if (SignExtend32<24>(delta) != delta)
909 llvm_unreachable("Relocation R_PPC64_REL24 overflow");
910 // Generates a 'bl <address>' instruction
911 writeInt32BE(LocalAddress, 0x48000001 | (delta & 0x03FFFFFC));
913 case ELF::R_PPC64_REL32: {
914 uint64_t FinalAddress = (Section.LoadAddress + Offset);
915 int32_t delta = static_cast<int32_t>(Value - FinalAddress + Addend);
916 if (SignExtend32<32>(delta) != delta)
917 llvm_unreachable("Relocation R_PPC64_REL32 overflow");
918 writeInt32BE(LocalAddress, delta);
920 case ELF::R_PPC64_REL64: {
921 uint64_t FinalAddress = (Section.LoadAddress + Offset);
922 uint64_t Delta = Value - FinalAddress + Addend;
923 writeInt64BE(LocalAddress, Delta);
925 case ELF::R_PPC64_ADDR64:
926 writeInt64BE(LocalAddress, Value + Addend);
931 void RuntimeDyldELF::resolveSystemZRelocation(const SectionEntry &Section,
932 uint64_t Offset, uint64_t Value,
933 uint32_t Type, int64_t Addend) {
934 uint8_t *LocalAddress = Section.Address + Offset;
937 llvm_unreachable("Relocation type not implemented yet!");
939 case ELF::R_390_PC16DBL:
940 case ELF::R_390_PLT16DBL: {
941 int64_t Delta = (Value + Addend) - (Section.LoadAddress + Offset);
942 assert(int16_t(Delta / 2) * 2 == Delta && "R_390_PC16DBL overflow");
943 writeInt16BE(LocalAddress, Delta / 2);
946 case ELF::R_390_PC32DBL:
947 case ELF::R_390_PLT32DBL: {
948 int64_t Delta = (Value + Addend) - (Section.LoadAddress + Offset);
949 assert(int32_t(Delta / 2) * 2 == Delta && "R_390_PC32DBL overflow");
950 writeInt32BE(LocalAddress, Delta / 2);
953 case ELF::R_390_PC32: {
954 int64_t Delta = (Value + Addend) - (Section.LoadAddress + Offset);
955 assert(int32_t(Delta) == Delta && "R_390_PC32 overflow");
956 writeInt32BE(LocalAddress, Delta);
960 writeInt64BE(LocalAddress, Value + Addend);
965 // The target location for the relocation is described by RE.SectionID and
966 // RE.Offset. RE.SectionID can be used to find the SectionEntry. Each
967 // SectionEntry has three members describing its location.
968 // SectionEntry::Address is the address at which the section has been loaded
969 // into memory in the current (host) process. SectionEntry::LoadAddress is the
970 // address that the section will have in the target process.
971 // SectionEntry::ObjAddress is the address of the bits for this section in the
972 // original emitted object image (also in the current address space).
974 // Relocations will be applied as if the section were loaded at
975 // SectionEntry::LoadAddress, but they will be applied at an address based
976 // on SectionEntry::Address. SectionEntry::ObjAddress will be used to refer to
977 // Target memory contents if they are required for value calculations.
979 // The Value parameter here is the load address of the symbol for the
980 // relocation to be applied. For relocations which refer to symbols in the
981 // current object Value will be the LoadAddress of the section in which
982 // the symbol resides (RE.Addend provides additional information about the
983 // symbol location). For external symbols, Value will be the address of the
984 // symbol in the target address space.
985 void RuntimeDyldELF::resolveRelocation(const RelocationEntry &RE,
987 const SectionEntry &Section = Sections[RE.SectionID];
988 return resolveRelocation(Section, RE.Offset, Value, RE.RelType, RE.Addend,
989 RE.SymOffset, RE.SectionID);
992 void RuntimeDyldELF::resolveRelocation(const SectionEntry &Section,
993 uint64_t Offset, uint64_t Value,
994 uint32_t Type, int64_t Addend,
995 uint64_t SymOffset, SID SectionID) {
998 resolveX86_64Relocation(Section, Offset, Value, Type, Addend, SymOffset);
1001 resolveX86Relocation(Section, Offset, (uint32_t)(Value & 0xffffffffL), Type,
1002 (uint32_t)(Addend & 0xffffffffL));
1004 case Triple::aarch64:
1005 case Triple::aarch64_be:
1006 resolveAArch64Relocation(Section, Offset, Value, Type, Addend);
1008 case Triple::arm: // Fall through.
1011 case Triple::thumbeb:
1012 resolveARMRelocation(Section, Offset, (uint32_t)(Value & 0xffffffffL), Type,
1013 (uint32_t)(Addend & 0xffffffffL));
1015 case Triple::mips: // Fall through.
1016 case Triple::mipsel:
1017 case Triple::mips64:
1018 case Triple::mips64el:
1020 resolveMIPSRelocation(Section, Offset, (uint32_t)(Value & 0xffffffffL),
1021 Type, (uint32_t)(Addend & 0xffffffffL));
1022 else if (IsMipsN64ABI)
1023 resolveMIPS64Relocation(Section, Offset, Value, Type, Addend, SymOffset,
1026 llvm_unreachable("Mips ABI not handled");
1028 case Triple::ppc64: // Fall through.
1029 case Triple::ppc64le:
1030 resolvePPC64Relocation(Section, Offset, Value, Type, Addend);
1032 case Triple::systemz:
1033 resolveSystemZRelocation(Section, Offset, Value, Type, Addend);
1036 llvm_unreachable("Unsupported CPU type!");
1040 void *RuntimeDyldELF::computePlaceholderAddress(unsigned SectionID, uint64_t Offset) const {
1041 return (void*)(Sections[SectionID].ObjAddress + Offset);
1044 void RuntimeDyldELF::processSimpleRelocation(unsigned SectionID, uint64_t Offset, unsigned RelType, RelocationValueRef Value) {
1045 RelocationEntry RE(SectionID, Offset, RelType, Value.Addend, Value.Offset);
1046 if (Value.SymbolName)
1047 addRelocationForSymbol(RE, Value.SymbolName);
1049 addRelocationForSection(RE, Value.SectionID);
1052 relocation_iterator RuntimeDyldELF::processRelocationRef(
1053 unsigned SectionID, relocation_iterator RelI,
1054 const ObjectFile &Obj,
1055 ObjSectionToIDMap &ObjSectionToID,
1058 Check(RelI->getType(RelType));
1060 Check(getELFRelocationAddend(*RelI, Addend));
1061 symbol_iterator Symbol = RelI->getSymbol();
1063 // Obtain the symbol name which is referenced in the relocation
1064 StringRef TargetName;
1065 if (Symbol != Obj.symbol_end())
1066 Symbol->getName(TargetName);
1067 DEBUG(dbgs() << "\t\tRelType: " << RelType << " Addend: " << Addend
1068 << " TargetName: " << TargetName << "\n");
1069 RelocationValueRef Value;
1070 // First search for the symbol in the local symbol table
1071 SymbolRef::Type SymType = SymbolRef::ST_Unknown;
1073 // Search for the symbol in the global symbol table
1074 RTDyldSymbolTable::const_iterator gsi = GlobalSymbolTable.end();
1075 if (Symbol != Obj.symbol_end()) {
1076 gsi = GlobalSymbolTable.find(TargetName.data());
1077 Symbol->getType(SymType);
1079 if (gsi != GlobalSymbolTable.end()) {
1080 const auto &SymInfo = gsi->second;
1081 Value.SectionID = SymInfo.getSectionID();
1082 Value.Offset = SymInfo.getOffset();
1083 Value.Addend = SymInfo.getOffset() + Addend;
1086 case SymbolRef::ST_Debug: {
1087 // TODO: Now ELF SymbolRef::ST_Debug = STT_SECTION, it's not obviously
1088 // and can be changed by another developers. Maybe best way is add
1089 // a new symbol type ST_Section to SymbolRef and use it.
1090 section_iterator si(Obj.section_end());
1091 Symbol->getSection(si);
1092 if (si == Obj.section_end())
1093 llvm_unreachable("Symbol section not found, bad object file format!");
1094 DEBUG(dbgs() << "\t\tThis is section symbol\n");
1095 bool isCode = si->isText();
1096 Value.SectionID = findOrEmitSection(Obj, (*si), isCode, ObjSectionToID);
1097 Value.Addend = Addend;
1100 case SymbolRef::ST_Data:
1101 case SymbolRef::ST_Unknown: {
1102 Value.SymbolName = TargetName.data();
1103 Value.Addend = Addend;
1105 // Absolute relocations will have a zero symbol ID (STN_UNDEF), which
1106 // will manifest here as a NULL symbol name.
1107 // We can set this as a valid (but empty) symbol name, and rely
1108 // on addRelocationForSymbol to handle this.
1109 if (!Value.SymbolName)
1110 Value.SymbolName = "";
1114 llvm_unreachable("Unresolved symbol type!");
1120 Check(RelI->getOffset(Offset));
1122 DEBUG(dbgs() << "\t\tSectionID: " << SectionID << " Offset: " << Offset
1124 if ((Arch == Triple::aarch64 || Arch == Triple::aarch64_be) &&
1125 (RelType == ELF::R_AARCH64_CALL26 || RelType == ELF::R_AARCH64_JUMP26)) {
1126 // This is an AArch64 branch relocation, need to use a stub function.
1127 DEBUG(dbgs() << "\t\tThis is an AArch64 branch relocation.");
1128 SectionEntry &Section = Sections[SectionID];
1130 // Look for an existing stub.
1131 StubMap::const_iterator i = Stubs.find(Value);
1132 if (i != Stubs.end()) {
1133 resolveRelocation(Section, Offset, (uint64_t)Section.Address + i->second,
1135 DEBUG(dbgs() << " Stub function found\n");
1137 // Create a new stub function.
1138 DEBUG(dbgs() << " Create a new stub function\n");
1139 Stubs[Value] = Section.StubOffset;
1140 uint8_t *StubTargetAddr =
1141 createStubFunction(Section.Address + Section.StubOffset);
1143 RelocationEntry REmovz_g3(SectionID, StubTargetAddr - Section.Address,
1144 ELF::R_AARCH64_MOVW_UABS_G3, Value.Addend);
1145 RelocationEntry REmovk_g2(SectionID, StubTargetAddr - Section.Address + 4,
1146 ELF::R_AARCH64_MOVW_UABS_G2_NC, Value.Addend);
1147 RelocationEntry REmovk_g1(SectionID, StubTargetAddr - Section.Address + 8,
1148 ELF::R_AARCH64_MOVW_UABS_G1_NC, Value.Addend);
1149 RelocationEntry REmovk_g0(SectionID,
1150 StubTargetAddr - Section.Address + 12,
1151 ELF::R_AARCH64_MOVW_UABS_G0_NC, Value.Addend);
1153 if (Value.SymbolName) {
1154 addRelocationForSymbol(REmovz_g3, Value.SymbolName);
1155 addRelocationForSymbol(REmovk_g2, Value.SymbolName);
1156 addRelocationForSymbol(REmovk_g1, Value.SymbolName);
1157 addRelocationForSymbol(REmovk_g0, Value.SymbolName);
1159 addRelocationForSection(REmovz_g3, Value.SectionID);
1160 addRelocationForSection(REmovk_g2, Value.SectionID);
1161 addRelocationForSection(REmovk_g1, Value.SectionID);
1162 addRelocationForSection(REmovk_g0, Value.SectionID);
1164 resolveRelocation(Section, Offset,
1165 (uint64_t)Section.Address + Section.StubOffset, RelType,
1167 Section.StubOffset += getMaxStubSize();
1169 } else if (Arch == Triple::arm) {
1170 if (RelType == ELF::R_ARM_PC24 || RelType == ELF::R_ARM_CALL ||
1171 RelType == ELF::R_ARM_JUMP24) {
1172 // This is an ARM branch relocation, need to use a stub function.
1173 DEBUG(dbgs() << "\t\tThis is an ARM branch relocation.");
1174 SectionEntry &Section = Sections[SectionID];
1176 // Look for an existing stub.
1177 StubMap::const_iterator i = Stubs.find(Value);
1178 if (i != Stubs.end()) {
1179 resolveRelocation(Section, Offset, (uint64_t)Section.Address + i->second,
1181 DEBUG(dbgs() << " Stub function found\n");
1183 // Create a new stub function.
1184 DEBUG(dbgs() << " Create a new stub function\n");
1185 Stubs[Value] = Section.StubOffset;
1186 uint8_t *StubTargetAddr =
1187 createStubFunction(Section.Address + Section.StubOffset);
1188 RelocationEntry RE(SectionID, StubTargetAddr - Section.Address,
1189 ELF::R_ARM_ABS32, Value.Addend);
1190 if (Value.SymbolName)
1191 addRelocationForSymbol(RE, Value.SymbolName);
1193 addRelocationForSection(RE, Value.SectionID);
1195 resolveRelocation(Section, Offset,
1196 (uint64_t)Section.Address + Section.StubOffset, RelType,
1198 Section.StubOffset += getMaxStubSize();
1201 uint32_t *Placeholder =
1202 reinterpret_cast<uint32_t*>(computePlaceholderAddress(SectionID, Offset));
1203 if (RelType == ELF::R_ARM_PREL31 || RelType == ELF::R_ARM_TARGET1 ||
1204 RelType == ELF::R_ARM_ABS32) {
1205 Value.Addend += *Placeholder;
1206 } else if (RelType == ELF::R_ARM_MOVW_ABS_NC || RelType == ELF::R_ARM_MOVT_ABS) {
1207 // See ELF for ARM documentation
1208 Value.Addend += (int16_t)((*Placeholder & 0xFFF) | (((*Placeholder >> 16) & 0xF) << 12));
1210 processSimpleRelocation(SectionID, Offset, RelType, Value);
1212 } else if (IsMipsO32ABI) {
1213 uint8_t *Placeholder = reinterpret_cast<uint8_t *>(
1214 computePlaceholderAddress(SectionID, Offset));
1215 uint32_t Opcode = readBytesUnaligned(Placeholder, 4);
1216 if (RelType == ELF::R_MIPS_26) {
1217 // This is an Mips branch relocation, need to use a stub function.
1218 DEBUG(dbgs() << "\t\tThis is a Mips branch relocation.");
1219 SectionEntry &Section = Sections[SectionID];
1221 // Extract the addend from the instruction.
1222 // We shift up by two since the Value will be down shifted again
1223 // when applying the relocation.
1224 uint32_t Addend = (Opcode & 0x03ffffff) << 2;
1226 Value.Addend += Addend;
1228 // Look up for existing stub.
1229 StubMap::const_iterator i = Stubs.find(Value);
1230 if (i != Stubs.end()) {
1231 RelocationEntry RE(SectionID, Offset, RelType, i->second);
1232 addRelocationForSection(RE, SectionID);
1233 DEBUG(dbgs() << " Stub function found\n");
1235 // Create a new stub function.
1236 DEBUG(dbgs() << " Create a new stub function\n");
1237 Stubs[Value] = Section.StubOffset;
1238 uint8_t *StubTargetAddr =
1239 createStubFunction(Section.Address + Section.StubOffset);
1241 // Creating Hi and Lo relocations for the filled stub instructions.
1242 RelocationEntry REHi(SectionID, StubTargetAddr - Section.Address,
1243 ELF::R_MIPS_HI16, Value.Addend);
1244 RelocationEntry RELo(SectionID, StubTargetAddr - Section.Address + 4,
1245 ELF::R_MIPS_LO16, Value.Addend);
1247 if (Value.SymbolName) {
1248 addRelocationForSymbol(REHi, Value.SymbolName);
1249 addRelocationForSymbol(RELo, Value.SymbolName);
1252 addRelocationForSection(REHi, Value.SectionID);
1253 addRelocationForSection(RELo, Value.SectionID);
1256 RelocationEntry RE(SectionID, Offset, RelType, Section.StubOffset);
1257 addRelocationForSection(RE, SectionID);
1258 Section.StubOffset += getMaxStubSize();
1261 if (RelType == ELF::R_MIPS_HI16)
1262 Value.Addend += (Opcode & 0x0000ffff) << 16;
1263 else if (RelType == ELF::R_MIPS_LO16)
1264 Value.Addend += (Opcode & 0x0000ffff);
1265 else if (RelType == ELF::R_MIPS_32)
1266 Value.Addend += Opcode;
1267 processSimpleRelocation(SectionID, Offset, RelType, Value);
1269 } else if (IsMipsN64ABI) {
1270 uint32_t r_type = RelType & 0xff;
1271 RelocationEntry RE(SectionID, Offset, RelType, Value.Addend);
1272 if (r_type == ELF::R_MIPS_CALL16 || r_type == ELF::R_MIPS_GOT_PAGE
1273 || r_type == ELF::R_MIPS_GOT_DISP) {
1274 StringMap<uint64_t>::iterator i = GOTSymbolOffsets.find(TargetName);
1275 if (i != GOTSymbolOffsets.end())
1276 RE.SymOffset = i->second;
1278 RE.SymOffset = allocateGOTEntries(SectionID, 1);
1279 GOTSymbolOffsets[TargetName] = RE.SymOffset;
1282 if (Value.SymbolName)
1283 addRelocationForSymbol(RE, Value.SymbolName);
1285 addRelocationForSection(RE, Value.SectionID);
1286 } else if (Arch == Triple::ppc64 || Arch == Triple::ppc64le) {
1287 if (RelType == ELF::R_PPC64_REL24) {
1288 // Determine ABI variant in use for this object.
1289 unsigned AbiVariant;
1290 Obj.getPlatformFlags(AbiVariant);
1291 AbiVariant &= ELF::EF_PPC64_ABI;
1292 // A PPC branch relocation will need a stub function if the target is
1293 // an external symbol (Symbol::ST_Unknown) or if the target address
1294 // is not within the signed 24-bits branch address.
1295 SectionEntry &Section = Sections[SectionID];
1296 uint8_t *Target = Section.Address + Offset;
1297 bool RangeOverflow = false;
1298 if (SymType != SymbolRef::ST_Unknown) {
1299 if (AbiVariant != 2) {
1300 // In the ELFv1 ABI, a function call may point to the .opd entry,
1301 // so the final symbol value is calculated based on the relocation
1302 // values in the .opd section.
1303 findOPDEntrySection(Obj, ObjSectionToID, Value);
1305 // In the ELFv2 ABI, a function symbol may provide a local entry
1306 // point, which must be used for direct calls.
1308 Symbol->getOther(SymOther);
1309 Value.Addend += ELF::decodePPC64LocalEntryOffset(SymOther);
1311 uint8_t *RelocTarget = Sections[Value.SectionID].Address + Value.Addend;
1312 int32_t delta = static_cast<int32_t>(Target - RelocTarget);
1313 // If it is within 24-bits branch range, just set the branch target
1314 if (SignExtend32<24>(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 (uint64_t)Section.Address + i->second, RelType, 0);
1332 DEBUG(dbgs() << " Stub function found\n");
1334 // Create a new stub function.
1335 DEBUG(dbgs() << " Create a new stub function\n");
1336 Stubs[Value] = Section.StubOffset;
1337 uint8_t *StubTargetAddr =
1338 createStubFunction(Section.Address + Section.StubOffset,
1340 RelocationEntry RE(SectionID, StubTargetAddr - Section.Address,
1341 ELF::R_PPC64_ADDR64, Value.Addend);
1343 // Generates the 64-bits address loads as exemplified in section
1344 // 4.5.1 in PPC64 ELF ABI. Note that the relocations need to
1345 // apply to the low part of the instructions, so we have to update
1346 // the offset according to the target endianness.
1347 uint64_t StubRelocOffset = StubTargetAddr - Section.Address;
1348 if (!IsTargetLittleEndian)
1349 StubRelocOffset += 2;
1351 RelocationEntry REhst(SectionID, StubRelocOffset + 0,
1352 ELF::R_PPC64_ADDR16_HIGHEST, Value.Addend);
1353 RelocationEntry REhr(SectionID, StubRelocOffset + 4,
1354 ELF::R_PPC64_ADDR16_HIGHER, Value.Addend);
1355 RelocationEntry REh(SectionID, StubRelocOffset + 12,
1356 ELF::R_PPC64_ADDR16_HI, Value.Addend);
1357 RelocationEntry REl(SectionID, StubRelocOffset + 16,
1358 ELF::R_PPC64_ADDR16_LO, Value.Addend);
1360 if (Value.SymbolName) {
1361 addRelocationForSymbol(REhst, Value.SymbolName);
1362 addRelocationForSymbol(REhr, Value.SymbolName);
1363 addRelocationForSymbol(REh, Value.SymbolName);
1364 addRelocationForSymbol(REl, Value.SymbolName);
1366 addRelocationForSection(REhst, Value.SectionID);
1367 addRelocationForSection(REhr, Value.SectionID);
1368 addRelocationForSection(REh, Value.SectionID);
1369 addRelocationForSection(REl, Value.SectionID);
1372 resolveRelocation(Section, Offset,
1373 (uint64_t)Section.Address + Section.StubOffset,
1375 Section.StubOffset += getMaxStubSize();
1377 if (SymType == SymbolRef::ST_Unknown) {
1378 // Restore the TOC for external calls
1379 if (AbiVariant == 2)
1380 writeInt32BE(Target + 4, 0xE8410018); // ld r2,28(r1)
1382 writeInt32BE(Target + 4, 0xE8410028); // ld r2,40(r1)
1385 } else if (RelType == ELF::R_PPC64_TOC16 ||
1386 RelType == ELF::R_PPC64_TOC16_DS ||
1387 RelType == ELF::R_PPC64_TOC16_LO ||
1388 RelType == ELF::R_PPC64_TOC16_LO_DS ||
1389 RelType == ELF::R_PPC64_TOC16_HI ||
1390 RelType == ELF::R_PPC64_TOC16_HA) {
1391 // These relocations are supposed to subtract the TOC address from
1392 // the final value. This does not fit cleanly into the RuntimeDyld
1393 // scheme, since there may be *two* sections involved in determining
1394 // the relocation value (the section of the symbol refered to by the
1395 // relocation, and the TOC section associated with the current module).
1397 // Fortunately, these relocations are currently only ever generated
1398 // refering to symbols that themselves reside in the TOC, which means
1399 // that the two sections are actually the same. Thus they cancel out
1400 // and we can immediately resolve the relocation right now.
1402 case ELF::R_PPC64_TOC16: RelType = ELF::R_PPC64_ADDR16; break;
1403 case ELF::R_PPC64_TOC16_DS: RelType = ELF::R_PPC64_ADDR16_DS; break;
1404 case ELF::R_PPC64_TOC16_LO: RelType = ELF::R_PPC64_ADDR16_LO; break;
1405 case ELF::R_PPC64_TOC16_LO_DS: RelType = ELF::R_PPC64_ADDR16_LO_DS; break;
1406 case ELF::R_PPC64_TOC16_HI: RelType = ELF::R_PPC64_ADDR16_HI; break;
1407 case ELF::R_PPC64_TOC16_HA: RelType = ELF::R_PPC64_ADDR16_HA; break;
1408 default: llvm_unreachable("Wrong relocation type.");
1411 RelocationValueRef TOCValue;
1412 findPPC64TOCSection(Obj, ObjSectionToID, TOCValue);
1413 if (Value.SymbolName || Value.SectionID != TOCValue.SectionID)
1414 llvm_unreachable("Unsupported TOC relocation.");
1415 Value.Addend -= TOCValue.Addend;
1416 resolveRelocation(Sections[SectionID], Offset, Value.Addend, RelType, 0);
1418 // There are two ways to refer to the TOC address directly: either
1419 // via a ELF::R_PPC64_TOC relocation (where both symbol and addend are
1420 // ignored), or via any relocation that refers to the magic ".TOC."
1421 // symbols (in which case the addend is respected).
1422 if (RelType == ELF::R_PPC64_TOC) {
1423 RelType = ELF::R_PPC64_ADDR64;
1424 findPPC64TOCSection(Obj, ObjSectionToID, Value);
1425 } else if (TargetName == ".TOC.") {
1426 findPPC64TOCSection(Obj, ObjSectionToID, Value);
1427 Value.Addend += Addend;
1430 RelocationEntry RE(SectionID, Offset, RelType, Value.Addend);
1432 if (Value.SymbolName)
1433 addRelocationForSymbol(RE, Value.SymbolName);
1435 addRelocationForSection(RE, Value.SectionID);
1437 } else if (Arch == Triple::systemz &&
1438 (RelType == ELF::R_390_PLT32DBL || RelType == ELF::R_390_GOTENT)) {
1439 // Create function stubs for both PLT and GOT references, regardless of
1440 // whether the GOT reference is to data or code. The stub contains the
1441 // full address of the symbol, as needed by GOT references, and the
1442 // executable part only adds an overhead of 8 bytes.
1444 // We could try to conserve space by allocating the code and data
1445 // parts of the stub separately. However, as things stand, we allocate
1446 // a stub for every relocation, so using a GOT in JIT code should be
1447 // no less space efficient than using an explicit constant pool.
1448 DEBUG(dbgs() << "\t\tThis is a SystemZ indirect relocation.");
1449 SectionEntry &Section = Sections[SectionID];
1451 // Look for an existing stub.
1452 StubMap::const_iterator i = Stubs.find(Value);
1453 uintptr_t StubAddress;
1454 if (i != Stubs.end()) {
1455 StubAddress = uintptr_t(Section.Address) + i->second;
1456 DEBUG(dbgs() << " Stub function found\n");
1458 // Create a new stub function.
1459 DEBUG(dbgs() << " Create a new stub function\n");
1461 uintptr_t BaseAddress = uintptr_t(Section.Address);
1462 uintptr_t StubAlignment = getStubAlignment();
1463 StubAddress = (BaseAddress + Section.StubOffset + StubAlignment - 1) &
1465 unsigned StubOffset = StubAddress - BaseAddress;
1467 Stubs[Value] = StubOffset;
1468 createStubFunction((uint8_t *)StubAddress);
1469 RelocationEntry RE(SectionID, StubOffset + 8, ELF::R_390_64,
1471 if (Value.SymbolName)
1472 addRelocationForSymbol(RE, Value.SymbolName);
1474 addRelocationForSection(RE, Value.SectionID);
1475 Section.StubOffset = StubOffset + getMaxStubSize();
1478 if (RelType == ELF::R_390_GOTENT)
1479 resolveRelocation(Section, Offset, StubAddress + 8, ELF::R_390_PC32DBL,
1482 resolveRelocation(Section, Offset, StubAddress, RelType, Addend);
1483 } else if (Arch == Triple::x86_64) {
1484 if (RelType == ELF::R_X86_64_PLT32) {
1485 // The way the PLT relocations normally work is that the linker allocates
1487 // PLT and this relocation makes a PC-relative call into the PLT. The PLT
1488 // entry will then jump to an address provided by the GOT. On first call,
1490 // GOT address will point back into PLT code that resolves the symbol. After
1491 // the first call, the GOT entry points to the actual function.
1493 // For local functions we're ignoring all of that here and just replacing
1494 // the PLT32 relocation type with PC32, which will translate the relocation
1495 // into a PC-relative call directly to the function. For external symbols we
1496 // can't be sure the function will be within 2^32 bytes of the call site, so
1497 // we need to create a stub, which calls into the GOT. This case is
1498 // equivalent to the usual PLT implementation except that we use the stub
1499 // mechanism in RuntimeDyld (which puts stubs at the end of the section)
1500 // rather than allocating a PLT section.
1501 if (Value.SymbolName) {
1502 // This is a call to an external function.
1503 // Look for an existing stub.
1504 SectionEntry &Section = Sections[SectionID];
1505 StubMap::const_iterator i = Stubs.find(Value);
1506 uintptr_t StubAddress;
1507 if (i != Stubs.end()) {
1508 StubAddress = uintptr_t(Section.Address) + i->second;
1509 DEBUG(dbgs() << " Stub function found\n");
1511 // Create a new stub function (equivalent to a PLT entry).
1512 DEBUG(dbgs() << " Create a new stub function\n");
1514 uintptr_t BaseAddress = uintptr_t(Section.Address);
1515 uintptr_t StubAlignment = getStubAlignment();
1516 StubAddress = (BaseAddress + Section.StubOffset + StubAlignment - 1) &
1518 unsigned StubOffset = StubAddress - BaseAddress;
1519 Stubs[Value] = StubOffset;
1520 createStubFunction((uint8_t *)StubAddress);
1522 // Bump our stub offset counter
1523 Section.StubOffset = StubOffset + getMaxStubSize();
1525 // Allocate a GOT Entry
1526 uint64_t GOTOffset = allocateGOTEntries(SectionID, 1);
1528 // The load of the GOT address has an addend of -4
1529 resolveGOTOffsetRelocation(SectionID, StubOffset + 2, GOTOffset - 4);
1531 // Fill in the value of the symbol we're targeting into the GOT
1532 addRelocationForSymbol(computeGOTOffsetRE(SectionID,GOTOffset,0,ELF::R_X86_64_64),
1536 // Make the target call a call into the stub table.
1537 resolveRelocation(Section, Offset, StubAddress, ELF::R_X86_64_PC32,
1540 RelocationEntry RE(SectionID, Offset, ELF::R_X86_64_PC32, Value.Addend,
1542 addRelocationForSection(RE, Value.SectionID);
1544 } else if (RelType == ELF::R_X86_64_GOTPCREL) {
1545 uint64_t GOTOffset = allocateGOTEntries(SectionID, 1);
1546 resolveGOTOffsetRelocation(SectionID, Offset, GOTOffset + Addend);
1548 // Fill in the value of the symbol we're targeting into the GOT
1549 RelocationEntry RE = computeGOTOffsetRE(SectionID, GOTOffset, Value.Offset, ELF::R_X86_64_64);
1550 if (Value.SymbolName)
1551 addRelocationForSymbol(RE, Value.SymbolName);
1553 addRelocationForSection(RE, Value.SectionID);
1554 } else if (RelType == ELF::R_X86_64_PC32) {
1555 Value.Addend += support::ulittle32_t::ref(computePlaceholderAddress(SectionID, Offset));
1556 processSimpleRelocation(SectionID, Offset, RelType, Value);
1557 } else if (RelType == ELF::R_X86_64_PC64) {
1558 Value.Addend += support::ulittle64_t::ref(computePlaceholderAddress(SectionID, Offset));
1559 processSimpleRelocation(SectionID, Offset, RelType, Value);
1561 processSimpleRelocation(SectionID, Offset, RelType, Value);
1564 if (Arch == Triple::x86) {
1565 Value.Addend += support::ulittle32_t::ref(computePlaceholderAddress(SectionID, Offset));
1567 processSimpleRelocation(SectionID, Offset, RelType, Value);
1572 size_t RuntimeDyldELF::getGOTEntrySize() {
1573 // We don't use the GOT in all of these cases, but it's essentially free
1574 // to put them all here.
1577 case Triple::x86_64:
1578 case Triple::aarch64:
1579 case Triple::aarch64_be:
1581 case Triple::ppc64le:
1582 case Triple::systemz:
1583 Result = sizeof(uint64_t);
1588 Result = sizeof(uint32_t);
1591 case Triple::mipsel:
1592 case Triple::mips64:
1593 case Triple::mips64el:
1595 Result = sizeof(uint32_t);
1596 else if (IsMipsN64ABI)
1597 Result = sizeof(uint64_t);
1599 llvm_unreachable("Mips ABI not handled");
1602 llvm_unreachable("Unsupported CPU type!");
1607 uint64_t RuntimeDyldELF::allocateGOTEntries(unsigned SectionID, unsigned no)
1609 (void)SectionID; // The GOT Section is the same for all section in the object file
1610 if (GOTSectionID == 0) {
1611 GOTSectionID = Sections.size();
1612 // Reserve a section id. We'll allocate the section later
1613 // once we know the total size
1614 Sections.push_back(SectionEntry(".got", 0, 0, 0));
1616 uint64_t StartOffset = CurrentGOTIndex * getGOTEntrySize();
1617 CurrentGOTIndex += no;
1621 void RuntimeDyldELF::resolveGOTOffsetRelocation(unsigned SectionID, uint64_t Offset, uint64_t GOTOffset)
1623 // Fill in the relative address of the GOT Entry into the stub
1624 RelocationEntry GOTRE(SectionID, Offset, ELF::R_X86_64_PC32, GOTOffset);
1625 addRelocationForSection(GOTRE, GOTSectionID);
1628 RelocationEntry RuntimeDyldELF::computeGOTOffsetRE(unsigned SectionID, uint64_t GOTOffset, uint64_t SymbolOffset,
1631 (void)SectionID; // The GOT Section is the same for all section in the object file
1632 return RelocationEntry(GOTSectionID, GOTOffset, Type, SymbolOffset);
1635 void RuntimeDyldELF::finalizeLoad(const ObjectFile &Obj,
1636 ObjSectionToIDMap &SectionMap) {
1637 // If necessary, allocate the global offset table
1638 if (GOTSectionID != 0) {
1639 // Allocate memory for the section
1640 size_t TotalSize = CurrentGOTIndex * getGOTEntrySize();
1641 uint8_t *Addr = MemMgr.allocateDataSection(TotalSize, getGOTEntrySize(),
1642 GOTSectionID, ".got", false);
1644 report_fatal_error("Unable to allocate memory for GOT!");
1646 Sections[GOTSectionID] = SectionEntry(".got", Addr, TotalSize, 0);
1649 Checker->registerSection(Obj.getFileName(), GOTSectionID);
1651 // For now, initialize all GOT entries to zero. We'll fill them in as
1652 // needed when GOT-based relocations are applied.
1653 memset(Addr, 0, TotalSize);
1655 // To correctly resolve Mips GOT relocations, we need a mapping from
1656 // object's sections to GOTs.
1657 for (section_iterator SI = Obj.section_begin(), SE = Obj.section_end();
1659 if (SI->relocation_begin() != SI->relocation_end()) {
1660 section_iterator RelocatedSection = SI->getRelocatedSection();
1661 ObjSectionToIDMap::iterator i = SectionMap.find(*RelocatedSection);
1662 assert (i != SectionMap.end());
1663 SectionToGOTMap[i->second] = GOTSectionID;
1666 GOTSymbolOffsets.clear();
1670 // Look for and record the EH frame section.
1671 ObjSectionToIDMap::iterator i, e;
1672 for (i = SectionMap.begin(), e = SectionMap.end(); i != e; ++i) {
1673 const SectionRef &Section = i->first;
1675 Section.getName(Name);
1676 if (Name == ".eh_frame") {
1677 UnregisteredEHFrameSections.push_back(i->second);
1683 CurrentGOTIndex = 0;
1686 bool RuntimeDyldELF::isCompatibleFile(const object::ObjectFile &Obj) const {