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 (Arch == Triple::UnknownArch ||
523 !StringRef(Triple::getArchTypePrefix(Arch)).equals("mips")) {
524 IsMipsO32ABI = false;
525 IsMipsN64ABI = false;
529 Obj.getPlatformFlags(AbiVariant);
530 IsMipsO32ABI = AbiVariant & ELF::EF_MIPS_ABI_O32;
531 IsMipsN64ABI = Obj.getFileFormatName().equals("ELF64-mips");
532 if (AbiVariant & ELF::EF_MIPS_ABI2)
533 llvm_unreachable("Mips N32 ABI is not supported yet");
536 void RuntimeDyldELF::resolveMIPS64Relocation(const SectionEntry &Section,
537 uint64_t Offset, uint64_t Value,
538 uint32_t Type, int64_t Addend,
541 uint32_t r_type = Type & 0xff;
542 uint32_t r_type2 = (Type >> 8) & 0xff;
543 uint32_t r_type3 = (Type >> 16) & 0xff;
545 // RelType is used to keep information for which relocation type we are
546 // applying relocation.
547 uint32_t RelType = r_type;
548 int64_t CalculatedValue = evaluateMIPS64Relocation(Section, Offset, Value,
550 SymOffset, SectionID);
551 if (r_type2 != ELF::R_MIPS_NONE) {
553 CalculatedValue = evaluateMIPS64Relocation(Section, Offset, 0, RelType,
554 CalculatedValue, SymOffset,
557 if (r_type3 != ELF::R_MIPS_NONE) {
559 CalculatedValue = evaluateMIPS64Relocation(Section, Offset, 0, RelType,
560 CalculatedValue, SymOffset,
563 applyMIPS64Relocation(Section.Address + Offset, CalculatedValue, RelType);
567 RuntimeDyldELF::evaluateMIPS64Relocation(const SectionEntry &Section,
568 uint64_t Offset, uint64_t Value,
569 uint32_t Type, int64_t Addend,
570 uint64_t SymOffset, SID SectionID) {
572 DEBUG(dbgs() << "evaluateMIPS64Relocation, LocalAddress: 0x"
573 << format("%llx", Section.Address + Offset)
574 << " FinalAddress: 0x"
575 << format("%llx", Section.LoadAddress + Offset)
576 << " Value: 0x" << format("%llx", Value) << " Type: 0x"
577 << format("%x", Type) << " Addend: 0x" << format("%llx", Addend)
578 << " SymOffset: " << format("%x", SymOffset)
583 llvm_unreachable("Not implemented relocation type!");
585 case ELF::R_MIPS_JALR:
586 case ELF::R_MIPS_NONE:
590 return Value + Addend;
592 return ((Value + Addend) >> 2) & 0x3ffffff;
593 case ELF::R_MIPS_GPREL16: {
594 uint64_t GOTAddr = getSectionLoadAddress(SectionToGOTMap[SectionID]);
595 return Value + Addend - (GOTAddr + 0x7ff0);
597 case ELF::R_MIPS_SUB:
598 return Value - Addend;
599 case ELF::R_MIPS_HI16:
600 // Get the higher 16-bits. Also add 1 if bit 15 is 1.
601 return ((Value + Addend + 0x8000) >> 16) & 0xffff;
602 case ELF::R_MIPS_LO16:
603 return (Value + Addend) & 0xffff;
604 case ELF::R_MIPS_CALL16:
605 case ELF::R_MIPS_GOT_DISP:
606 case ELF::R_MIPS_GOT_PAGE: {
607 uint8_t *LocalGOTAddr =
608 getSectionAddress(SectionToGOTMap[SectionID]) + SymOffset;
609 uint64_t GOTEntry = readBytesUnaligned(LocalGOTAddr, 8);
612 if (Type == ELF::R_MIPS_GOT_PAGE)
613 Value = (Value + 0x8000) & ~0xffff;
616 assert(GOTEntry == Value &&
617 "GOT entry has two different addresses.");
619 writeBytesUnaligned(Value, LocalGOTAddr, 8);
621 return (SymOffset - 0x7ff0) & 0xffff;
623 case ELF::R_MIPS_GOT_OFST: {
624 int64_t page = (Value + Addend + 0x8000) & ~0xffff;
625 return (Value + Addend - page) & 0xffff;
627 case ELF::R_MIPS_GPREL32: {
628 uint64_t GOTAddr = getSectionLoadAddress(SectionToGOTMap[SectionID]);
629 return Value + Addend - (GOTAddr + 0x7ff0);
631 case ELF::R_MIPS_PC16: {
632 uint64_t FinalAddress = (Section.LoadAddress + Offset);
633 return ((Value + Addend - FinalAddress) >> 2) & 0xffff;
635 case ELF::R_MIPS_PC32: {
636 uint64_t FinalAddress = (Section.LoadAddress + Offset);
637 return Value + Addend - FinalAddress;
639 case ELF::R_MIPS_PC18_S3: {
640 uint64_t FinalAddress = (Section.LoadAddress + Offset);
641 return ((Value + Addend - ((FinalAddress | 7) ^ 7)) >> 3) & 0x3ffff;
643 case ELF::R_MIPS_PC19_S2: {
644 uint64_t FinalAddress = (Section.LoadAddress + Offset);
645 return ((Value + Addend - FinalAddress) >> 2) & 0x7ffff;
647 case ELF::R_MIPS_PC21_S2: {
648 uint64_t FinalAddress = (Section.LoadAddress + Offset);
649 return ((Value + Addend - FinalAddress) >> 2) & 0x1fffff;
651 case ELF::R_MIPS_PC26_S2: {
652 uint64_t FinalAddress = (Section.LoadAddress + Offset);
653 return ((Value + Addend - FinalAddress) >> 2) & 0x3ffffff;
655 case ELF::R_MIPS_PCHI16: {
656 uint64_t FinalAddress = (Section.LoadAddress + Offset);
657 return ((Value + Addend - FinalAddress + 0x8000) >> 16) & 0xffff;
659 case ELF::R_MIPS_PCLO16: {
660 uint64_t FinalAddress = (Section.LoadAddress + Offset);
661 return (Value + Addend - FinalAddress) & 0xffff;
667 void RuntimeDyldELF::applyMIPS64Relocation(uint8_t *TargetPtr,
668 int64_t CalculatedValue,
670 uint32_t Insn = readBytesUnaligned(TargetPtr, 4);
676 case ELF::R_MIPS_GPREL32:
677 case ELF::R_MIPS_PC32:
678 writeBytesUnaligned(CalculatedValue & 0xffffffff, TargetPtr, 4);
681 case ELF::R_MIPS_SUB:
682 writeBytesUnaligned(CalculatedValue, TargetPtr, 8);
685 case ELF::R_MIPS_PC26_S2:
686 Insn = (Insn & 0xfc000000) | CalculatedValue;
687 writeBytesUnaligned(Insn, TargetPtr, 4);
689 case ELF::R_MIPS_GPREL16:
690 Insn = (Insn & 0xffff0000) | (CalculatedValue & 0xffff);
691 writeBytesUnaligned(Insn, TargetPtr, 4);
693 case ELF::R_MIPS_HI16:
694 case ELF::R_MIPS_LO16:
695 case ELF::R_MIPS_PCHI16:
696 case ELF::R_MIPS_PCLO16:
697 case ELF::R_MIPS_PC16:
698 case ELF::R_MIPS_CALL16:
699 case ELF::R_MIPS_GOT_DISP:
700 case ELF::R_MIPS_GOT_PAGE:
701 case ELF::R_MIPS_GOT_OFST:
702 Insn = (Insn & 0xffff0000) | CalculatedValue;
703 writeBytesUnaligned(Insn, TargetPtr, 4);
705 case ELF::R_MIPS_PC18_S3:
706 Insn = (Insn & 0xfffc0000) | CalculatedValue;
707 writeBytesUnaligned(Insn, TargetPtr, 4);
709 case ELF::R_MIPS_PC19_S2:
710 Insn = (Insn & 0xfff80000) | CalculatedValue;
711 writeBytesUnaligned(Insn, TargetPtr, 4);
713 case ELF::R_MIPS_PC21_S2:
714 Insn = (Insn & 0xffe00000) | CalculatedValue;
715 writeBytesUnaligned(Insn, TargetPtr, 4);
720 // Return the .TOC. section and offset.
721 void RuntimeDyldELF::findPPC64TOCSection(const ELFObjectFileBase &Obj,
722 ObjSectionToIDMap &LocalSections,
723 RelocationValueRef &Rel) {
724 // Set a default SectionID in case we do not find a TOC section below.
725 // This may happen for references to TOC base base (sym@toc, .odp
726 // relocation) without a .toc directive. In this case just use the
727 // first section (which is usually the .odp) since the code won't
728 // reference the .toc base directly.
729 Rel.SymbolName = NULL;
732 // The TOC consists of sections .got, .toc, .tocbss, .plt in that
733 // order. The TOC starts where the first of these sections starts.
734 for (auto &Section: Obj.sections()) {
735 StringRef SectionName;
736 check(Section.getName(SectionName));
738 if (SectionName == ".got"
739 || SectionName == ".toc"
740 || SectionName == ".tocbss"
741 || SectionName == ".plt") {
742 Rel.SectionID = findOrEmitSection(Obj, Section, false, LocalSections);
747 // Per the ppc64-elf-linux ABI, The TOC base is TOC value plus 0x8000
748 // thus permitting a full 64 Kbytes segment.
752 // Returns the sections and offset associated with the ODP entry referenced
754 void RuntimeDyldELF::findOPDEntrySection(const ELFObjectFileBase &Obj,
755 ObjSectionToIDMap &LocalSections,
756 RelocationValueRef &Rel) {
757 // Get the ELF symbol value (st_value) to compare with Relocation offset in
759 for (section_iterator si = Obj.section_begin(), se = Obj.section_end();
761 section_iterator RelSecI = si->getRelocatedSection();
762 if (RelSecI == Obj.section_end())
765 StringRef RelSectionName;
766 check(RelSecI->getName(RelSectionName));
767 if (RelSectionName != ".opd")
770 for (relocation_iterator i = si->relocation_begin(),
771 e = si->relocation_end();
773 // The R_PPC64_ADDR64 relocation indicates the first field
776 check(i->getType(TypeFunc));
777 if (TypeFunc != ELF::R_PPC64_ADDR64) {
782 uint64_t TargetSymbolOffset = i->getOffset();
783 symbol_iterator TargetSymbol = i->getSymbol();
784 ErrorOr<int64_t> AddendOrErr =
785 Obj.getRelocationAddend(i->getRawDataRefImpl());
786 Check(AddendOrErr.getError());
787 int64_t Addend = *AddendOrErr;
793 // Just check if following relocation is a R_PPC64_TOC
795 check(i->getType(TypeTOC));
796 if (TypeTOC != ELF::R_PPC64_TOC)
799 // Finally compares the Symbol value and the target symbol offset
800 // to check if this .opd entry refers to the symbol the relocation
802 if (Rel.Addend != (int64_t)TargetSymbolOffset)
805 section_iterator tsi(Obj.section_end());
806 check(TargetSymbol->getSection(tsi));
807 bool IsCode = tsi->isText();
808 Rel.SectionID = findOrEmitSection(Obj, (*tsi), IsCode, LocalSections);
809 Rel.Addend = (intptr_t)Addend;
813 llvm_unreachable("Attempting to get address of ODP entry!");
816 // Relocation masks following the #lo(value), #hi(value), #ha(value),
817 // #higher(value), #highera(value), #highest(value), and #highesta(value)
818 // macros defined in section 4.5.1. Relocation Types of the PPC-elf64abi
821 static inline uint16_t applyPPClo(uint64_t value) { return value & 0xffff; }
823 static inline uint16_t applyPPChi(uint64_t value) {
824 return (value >> 16) & 0xffff;
827 static inline uint16_t applyPPCha (uint64_t value) {
828 return ((value + 0x8000) >> 16) & 0xffff;
831 static inline uint16_t applyPPChigher(uint64_t value) {
832 return (value >> 32) & 0xffff;
835 static inline uint16_t applyPPChighera (uint64_t value) {
836 return ((value + 0x8000) >> 32) & 0xffff;
839 static inline uint16_t applyPPChighest(uint64_t value) {
840 return (value >> 48) & 0xffff;
843 static inline uint16_t applyPPChighesta (uint64_t value) {
844 return ((value + 0x8000) >> 48) & 0xffff;
847 void RuntimeDyldELF::resolvePPC64Relocation(const SectionEntry &Section,
848 uint64_t Offset, uint64_t Value,
849 uint32_t Type, int64_t Addend) {
850 uint8_t *LocalAddress = Section.Address + Offset;
853 llvm_unreachable("Relocation type not implemented yet!");
855 case ELF::R_PPC64_ADDR16:
856 writeInt16BE(LocalAddress, applyPPClo(Value + Addend));
858 case ELF::R_PPC64_ADDR16_DS:
859 writeInt16BE(LocalAddress, applyPPClo(Value + Addend) & ~3);
861 case ELF::R_PPC64_ADDR16_LO:
862 writeInt16BE(LocalAddress, applyPPClo(Value + Addend));
864 case ELF::R_PPC64_ADDR16_LO_DS:
865 writeInt16BE(LocalAddress, applyPPClo(Value + Addend) & ~3);
867 case ELF::R_PPC64_ADDR16_HI:
868 writeInt16BE(LocalAddress, applyPPChi(Value + Addend));
870 case ELF::R_PPC64_ADDR16_HA:
871 writeInt16BE(LocalAddress, applyPPCha(Value + Addend));
873 case ELF::R_PPC64_ADDR16_HIGHER:
874 writeInt16BE(LocalAddress, applyPPChigher(Value + Addend));
876 case ELF::R_PPC64_ADDR16_HIGHERA:
877 writeInt16BE(LocalAddress, applyPPChighera(Value + Addend));
879 case ELF::R_PPC64_ADDR16_HIGHEST:
880 writeInt16BE(LocalAddress, applyPPChighest(Value + Addend));
882 case ELF::R_PPC64_ADDR16_HIGHESTA:
883 writeInt16BE(LocalAddress, applyPPChighesta(Value + Addend));
885 case ELF::R_PPC64_ADDR14: {
886 assert(((Value + Addend) & 3) == 0);
887 // Preserve the AA/LK bits in the branch instruction
888 uint8_t aalk = *(LocalAddress + 3);
889 writeInt16BE(LocalAddress + 2, (aalk & 3) | ((Value + Addend) & 0xfffc));
891 case ELF::R_PPC64_REL16_LO: {
892 uint64_t FinalAddress = (Section.LoadAddress + Offset);
893 uint64_t Delta = Value - FinalAddress + Addend;
894 writeInt16BE(LocalAddress, applyPPClo(Delta));
896 case ELF::R_PPC64_REL16_HI: {
897 uint64_t FinalAddress = (Section.LoadAddress + Offset);
898 uint64_t Delta = Value - FinalAddress + Addend;
899 writeInt16BE(LocalAddress, applyPPChi(Delta));
901 case ELF::R_PPC64_REL16_HA: {
902 uint64_t FinalAddress = (Section.LoadAddress + Offset);
903 uint64_t Delta = Value - FinalAddress + Addend;
904 writeInt16BE(LocalAddress, applyPPCha(Delta));
906 case ELF::R_PPC64_ADDR32: {
907 int32_t Result = static_cast<int32_t>(Value + Addend);
908 if (SignExtend32<32>(Result) != Result)
909 llvm_unreachable("Relocation R_PPC64_ADDR32 overflow");
910 writeInt32BE(LocalAddress, Result);
912 case ELF::R_PPC64_REL24: {
913 uint64_t FinalAddress = (Section.LoadAddress + Offset);
914 int32_t delta = static_cast<int32_t>(Value - FinalAddress + Addend);
915 if (SignExtend32<24>(delta) != delta)
916 llvm_unreachable("Relocation R_PPC64_REL24 overflow");
917 // Generates a 'bl <address>' instruction
918 writeInt32BE(LocalAddress, 0x48000001 | (delta & 0x03FFFFFC));
920 case ELF::R_PPC64_REL32: {
921 uint64_t FinalAddress = (Section.LoadAddress + Offset);
922 int32_t delta = static_cast<int32_t>(Value - FinalAddress + Addend);
923 if (SignExtend32<32>(delta) != delta)
924 llvm_unreachable("Relocation R_PPC64_REL32 overflow");
925 writeInt32BE(LocalAddress, delta);
927 case ELF::R_PPC64_REL64: {
928 uint64_t FinalAddress = (Section.LoadAddress + Offset);
929 uint64_t Delta = Value - FinalAddress + Addend;
930 writeInt64BE(LocalAddress, Delta);
932 case ELF::R_PPC64_ADDR64:
933 writeInt64BE(LocalAddress, Value + Addend);
938 void RuntimeDyldELF::resolveSystemZRelocation(const SectionEntry &Section,
939 uint64_t Offset, uint64_t Value,
940 uint32_t Type, int64_t Addend) {
941 uint8_t *LocalAddress = Section.Address + Offset;
944 llvm_unreachable("Relocation type not implemented yet!");
946 case ELF::R_390_PC16DBL:
947 case ELF::R_390_PLT16DBL: {
948 int64_t Delta = (Value + Addend) - (Section.LoadAddress + Offset);
949 assert(int16_t(Delta / 2) * 2 == Delta && "R_390_PC16DBL overflow");
950 writeInt16BE(LocalAddress, Delta / 2);
953 case ELF::R_390_PC32DBL:
954 case ELF::R_390_PLT32DBL: {
955 int64_t Delta = (Value + Addend) - (Section.LoadAddress + Offset);
956 assert(int32_t(Delta / 2) * 2 == Delta && "R_390_PC32DBL overflow");
957 writeInt32BE(LocalAddress, Delta / 2);
960 case ELF::R_390_PC32: {
961 int64_t Delta = (Value + Addend) - (Section.LoadAddress + Offset);
962 assert(int32_t(Delta) == Delta && "R_390_PC32 overflow");
963 writeInt32BE(LocalAddress, Delta);
967 writeInt64BE(LocalAddress, Value + Addend);
972 // The target location for the relocation is described by RE.SectionID and
973 // RE.Offset. RE.SectionID can be used to find the SectionEntry. Each
974 // SectionEntry has three members describing its location.
975 // SectionEntry::Address is the address at which the section has been loaded
976 // into memory in the current (host) process. SectionEntry::LoadAddress is the
977 // address that the section will have in the target process.
978 // SectionEntry::ObjAddress is the address of the bits for this section in the
979 // original emitted object image (also in the current address space).
981 // Relocations will be applied as if the section were loaded at
982 // SectionEntry::LoadAddress, but they will be applied at an address based
983 // on SectionEntry::Address. SectionEntry::ObjAddress will be used to refer to
984 // Target memory contents if they are required for value calculations.
986 // The Value parameter here is the load address of the symbol for the
987 // relocation to be applied. For relocations which refer to symbols in the
988 // current object Value will be the LoadAddress of the section in which
989 // the symbol resides (RE.Addend provides additional information about the
990 // symbol location). For external symbols, Value will be the address of the
991 // symbol in the target address space.
992 void RuntimeDyldELF::resolveRelocation(const RelocationEntry &RE,
994 const SectionEntry &Section = Sections[RE.SectionID];
995 return resolveRelocation(Section, RE.Offset, Value, RE.RelType, RE.Addend,
996 RE.SymOffset, RE.SectionID);
999 void RuntimeDyldELF::resolveRelocation(const SectionEntry &Section,
1000 uint64_t Offset, uint64_t Value,
1001 uint32_t Type, int64_t Addend,
1002 uint64_t SymOffset, SID SectionID) {
1004 case Triple::x86_64:
1005 resolveX86_64Relocation(Section, Offset, Value, Type, Addend, SymOffset);
1008 resolveX86Relocation(Section, Offset, (uint32_t)(Value & 0xffffffffL), Type,
1009 (uint32_t)(Addend & 0xffffffffL));
1011 case Triple::aarch64:
1012 case Triple::aarch64_be:
1013 resolveAArch64Relocation(Section, Offset, Value, Type, Addend);
1015 case Triple::arm: // Fall through.
1018 case Triple::thumbeb:
1019 resolveARMRelocation(Section, Offset, (uint32_t)(Value & 0xffffffffL), Type,
1020 (uint32_t)(Addend & 0xffffffffL));
1022 case Triple::mips: // Fall through.
1023 case Triple::mipsel:
1024 case Triple::mips64:
1025 case Triple::mips64el:
1027 resolveMIPSRelocation(Section, Offset, (uint32_t)(Value & 0xffffffffL),
1028 Type, (uint32_t)(Addend & 0xffffffffL));
1029 else if (IsMipsN64ABI)
1030 resolveMIPS64Relocation(Section, Offset, Value, Type, Addend, SymOffset,
1033 llvm_unreachable("Mips ABI not handled");
1035 case Triple::ppc64: // Fall through.
1036 case Triple::ppc64le:
1037 resolvePPC64Relocation(Section, Offset, Value, Type, Addend);
1039 case Triple::systemz:
1040 resolveSystemZRelocation(Section, Offset, Value, Type, Addend);
1043 llvm_unreachable("Unsupported CPU type!");
1047 void *RuntimeDyldELF::computePlaceholderAddress(unsigned SectionID, uint64_t Offset) const {
1048 return (void*)(Sections[SectionID].ObjAddress + Offset);
1051 void RuntimeDyldELF::processSimpleRelocation(unsigned SectionID, uint64_t Offset, unsigned RelType, RelocationValueRef Value) {
1052 RelocationEntry RE(SectionID, Offset, RelType, Value.Addend, Value.Offset);
1053 if (Value.SymbolName)
1054 addRelocationForSymbol(RE, Value.SymbolName);
1056 addRelocationForSection(RE, Value.SectionID);
1059 relocation_iterator RuntimeDyldELF::processRelocationRef(
1060 unsigned SectionID, relocation_iterator RelI, const ObjectFile &O,
1061 ObjSectionToIDMap &ObjSectionToID, StubMap &Stubs) {
1062 const auto &Obj = cast<ELFObjectFileBase>(O);
1064 Check(RelI->getType(RelType));
1066 if (Obj.hasRelocationAddend(RelI->getRawDataRefImpl()))
1067 Addend = *Obj.getRelocationAddend(RelI->getRawDataRefImpl());
1068 elf_symbol_iterator Symbol = RelI->getSymbol();
1070 // Obtain the symbol name which is referenced in the relocation
1071 StringRef TargetName;
1072 if (Symbol != Obj.symbol_end())
1073 Symbol->getName(TargetName);
1074 DEBUG(dbgs() << "\t\tRelType: " << RelType << " Addend: " << Addend
1075 << " TargetName: " << TargetName << "\n");
1076 RelocationValueRef Value;
1077 // First search for the symbol in the local symbol table
1078 SymbolRef::Type SymType = SymbolRef::ST_Unknown;
1080 // Search for the symbol in the global symbol table
1081 RTDyldSymbolTable::const_iterator gsi = GlobalSymbolTable.end();
1082 if (Symbol != Obj.symbol_end()) {
1083 gsi = GlobalSymbolTable.find(TargetName.data());
1084 SymType = Symbol->getType();
1086 if (gsi != GlobalSymbolTable.end()) {
1087 const auto &SymInfo = gsi->second;
1088 Value.SectionID = SymInfo.getSectionID();
1089 Value.Offset = SymInfo.getOffset();
1090 Value.Addend = SymInfo.getOffset() + Addend;
1093 case SymbolRef::ST_Debug: {
1094 // TODO: Now ELF SymbolRef::ST_Debug = STT_SECTION, it's not obviously
1095 // and can be changed by another developers. Maybe best way is add
1096 // a new symbol type ST_Section to SymbolRef and use it.
1097 section_iterator si(Obj.section_end());
1098 Symbol->getSection(si);
1099 if (si == Obj.section_end())
1100 llvm_unreachable("Symbol section not found, bad object file format!");
1101 DEBUG(dbgs() << "\t\tThis is section symbol\n");
1102 bool isCode = si->isText();
1103 Value.SectionID = findOrEmitSection(Obj, (*si), isCode, ObjSectionToID);
1104 Value.Addend = Addend;
1107 case SymbolRef::ST_Data:
1108 case SymbolRef::ST_Unknown: {
1109 Value.SymbolName = TargetName.data();
1110 Value.Addend = Addend;
1112 // Absolute relocations will have a zero symbol ID (STN_UNDEF), which
1113 // will manifest here as a NULL symbol name.
1114 // We can set this as a valid (but empty) symbol name, and rely
1115 // on addRelocationForSymbol to handle this.
1116 if (!Value.SymbolName)
1117 Value.SymbolName = "";
1121 llvm_unreachable("Unresolved symbol type!");
1126 uint64_t Offset = RelI->getOffset();
1128 DEBUG(dbgs() << "\t\tSectionID: " << SectionID << " Offset: " << Offset
1130 if ((Arch == Triple::aarch64 || Arch == Triple::aarch64_be) &&
1131 (RelType == ELF::R_AARCH64_CALL26 || RelType == ELF::R_AARCH64_JUMP26)) {
1132 // This is an AArch64 branch relocation, need to use a stub function.
1133 DEBUG(dbgs() << "\t\tThis is an AArch64 branch relocation.");
1134 SectionEntry &Section = Sections[SectionID];
1136 // Look for an existing stub.
1137 StubMap::const_iterator i = Stubs.find(Value);
1138 if (i != Stubs.end()) {
1139 resolveRelocation(Section, Offset, (uint64_t)Section.Address + i->second,
1141 DEBUG(dbgs() << " Stub function found\n");
1143 // Create a new stub function.
1144 DEBUG(dbgs() << " Create a new stub function\n");
1145 Stubs[Value] = Section.StubOffset;
1146 uint8_t *StubTargetAddr =
1147 createStubFunction(Section.Address + Section.StubOffset);
1149 RelocationEntry REmovz_g3(SectionID, StubTargetAddr - Section.Address,
1150 ELF::R_AARCH64_MOVW_UABS_G3, Value.Addend);
1151 RelocationEntry REmovk_g2(SectionID, StubTargetAddr - Section.Address + 4,
1152 ELF::R_AARCH64_MOVW_UABS_G2_NC, Value.Addend);
1153 RelocationEntry REmovk_g1(SectionID, StubTargetAddr - Section.Address + 8,
1154 ELF::R_AARCH64_MOVW_UABS_G1_NC, Value.Addend);
1155 RelocationEntry REmovk_g0(SectionID,
1156 StubTargetAddr - Section.Address + 12,
1157 ELF::R_AARCH64_MOVW_UABS_G0_NC, Value.Addend);
1159 if (Value.SymbolName) {
1160 addRelocationForSymbol(REmovz_g3, Value.SymbolName);
1161 addRelocationForSymbol(REmovk_g2, Value.SymbolName);
1162 addRelocationForSymbol(REmovk_g1, Value.SymbolName);
1163 addRelocationForSymbol(REmovk_g0, Value.SymbolName);
1165 addRelocationForSection(REmovz_g3, Value.SectionID);
1166 addRelocationForSection(REmovk_g2, Value.SectionID);
1167 addRelocationForSection(REmovk_g1, Value.SectionID);
1168 addRelocationForSection(REmovk_g0, Value.SectionID);
1170 resolveRelocation(Section, Offset,
1171 (uint64_t)Section.Address + Section.StubOffset, RelType,
1173 Section.StubOffset += getMaxStubSize();
1175 } else if (Arch == Triple::arm) {
1176 if (RelType == ELF::R_ARM_PC24 || RelType == ELF::R_ARM_CALL ||
1177 RelType == ELF::R_ARM_JUMP24) {
1178 // This is an ARM branch relocation, need to use a stub function.
1179 DEBUG(dbgs() << "\t\tThis is an ARM branch relocation.");
1180 SectionEntry &Section = Sections[SectionID];
1182 // Look for an existing stub.
1183 StubMap::const_iterator i = Stubs.find(Value);
1184 if (i != Stubs.end()) {
1185 resolveRelocation(Section, Offset, (uint64_t)Section.Address + i->second,
1187 DEBUG(dbgs() << " Stub function found\n");
1189 // Create a new stub function.
1190 DEBUG(dbgs() << " Create a new stub function\n");
1191 Stubs[Value] = Section.StubOffset;
1192 uint8_t *StubTargetAddr =
1193 createStubFunction(Section.Address + Section.StubOffset);
1194 RelocationEntry RE(SectionID, StubTargetAddr - Section.Address,
1195 ELF::R_ARM_ABS32, Value.Addend);
1196 if (Value.SymbolName)
1197 addRelocationForSymbol(RE, Value.SymbolName);
1199 addRelocationForSection(RE, Value.SectionID);
1201 resolveRelocation(Section, Offset,
1202 (uint64_t)Section.Address + Section.StubOffset, RelType,
1204 Section.StubOffset += getMaxStubSize();
1207 uint32_t *Placeholder =
1208 reinterpret_cast<uint32_t*>(computePlaceholderAddress(SectionID, Offset));
1209 if (RelType == ELF::R_ARM_PREL31 || RelType == ELF::R_ARM_TARGET1 ||
1210 RelType == ELF::R_ARM_ABS32) {
1211 Value.Addend += *Placeholder;
1212 } else if (RelType == ELF::R_ARM_MOVW_ABS_NC || RelType == ELF::R_ARM_MOVT_ABS) {
1213 // See ELF for ARM documentation
1214 Value.Addend += (int16_t)((*Placeholder & 0xFFF) | (((*Placeholder >> 16) & 0xF) << 12));
1216 processSimpleRelocation(SectionID, Offset, RelType, Value);
1218 } else if (IsMipsO32ABI) {
1219 uint8_t *Placeholder = reinterpret_cast<uint8_t *>(
1220 computePlaceholderAddress(SectionID, Offset));
1221 uint32_t Opcode = readBytesUnaligned(Placeholder, 4);
1222 if (RelType == ELF::R_MIPS_26) {
1223 // This is an Mips branch relocation, need to use a stub function.
1224 DEBUG(dbgs() << "\t\tThis is a Mips branch relocation.");
1225 SectionEntry &Section = Sections[SectionID];
1227 // Extract the addend from the instruction.
1228 // We shift up by two since the Value will be down shifted again
1229 // when applying the relocation.
1230 uint32_t Addend = (Opcode & 0x03ffffff) << 2;
1232 Value.Addend += Addend;
1234 // Look up for existing stub.
1235 StubMap::const_iterator i = Stubs.find(Value);
1236 if (i != Stubs.end()) {
1237 RelocationEntry RE(SectionID, Offset, RelType, i->second);
1238 addRelocationForSection(RE, SectionID);
1239 DEBUG(dbgs() << " Stub function found\n");
1241 // Create a new stub function.
1242 DEBUG(dbgs() << " Create a new stub function\n");
1243 Stubs[Value] = Section.StubOffset;
1244 uint8_t *StubTargetAddr =
1245 createStubFunction(Section.Address + Section.StubOffset);
1247 // Creating Hi and Lo relocations for the filled stub instructions.
1248 RelocationEntry REHi(SectionID, StubTargetAddr - Section.Address,
1249 ELF::R_MIPS_HI16, Value.Addend);
1250 RelocationEntry RELo(SectionID, StubTargetAddr - Section.Address + 4,
1251 ELF::R_MIPS_LO16, Value.Addend);
1253 if (Value.SymbolName) {
1254 addRelocationForSymbol(REHi, Value.SymbolName);
1255 addRelocationForSymbol(RELo, Value.SymbolName);
1258 addRelocationForSection(REHi, Value.SectionID);
1259 addRelocationForSection(RELo, Value.SectionID);
1262 RelocationEntry RE(SectionID, Offset, RelType, Section.StubOffset);
1263 addRelocationForSection(RE, SectionID);
1264 Section.StubOffset += getMaxStubSize();
1267 if (RelType == ELF::R_MIPS_HI16)
1268 Value.Addend += (Opcode & 0x0000ffff) << 16;
1269 else if (RelType == ELF::R_MIPS_LO16)
1270 Value.Addend += (Opcode & 0x0000ffff);
1271 else if (RelType == ELF::R_MIPS_32)
1272 Value.Addend += Opcode;
1273 processSimpleRelocation(SectionID, Offset, RelType, Value);
1275 } else if (IsMipsN64ABI) {
1276 uint32_t r_type = RelType & 0xff;
1277 RelocationEntry RE(SectionID, Offset, RelType, Value.Addend);
1278 if (r_type == ELF::R_MIPS_CALL16 || r_type == ELF::R_MIPS_GOT_PAGE
1279 || r_type == ELF::R_MIPS_GOT_DISP) {
1280 StringMap<uint64_t>::iterator i = GOTSymbolOffsets.find(TargetName);
1281 if (i != GOTSymbolOffsets.end())
1282 RE.SymOffset = i->second;
1284 RE.SymOffset = allocateGOTEntries(SectionID, 1);
1285 GOTSymbolOffsets[TargetName] = RE.SymOffset;
1288 if (Value.SymbolName)
1289 addRelocationForSymbol(RE, Value.SymbolName);
1291 addRelocationForSection(RE, Value.SectionID);
1292 } else if (Arch == Triple::ppc64 || Arch == Triple::ppc64le) {
1293 if (RelType == ELF::R_PPC64_REL24) {
1294 // Determine ABI variant in use for this object.
1295 unsigned AbiVariant;
1296 Obj.getPlatformFlags(AbiVariant);
1297 AbiVariant &= ELF::EF_PPC64_ABI;
1298 // A PPC branch relocation will need a stub function if the target is
1299 // an external symbol (Symbol::ST_Unknown) or if the target address
1300 // is not within the signed 24-bits branch address.
1301 SectionEntry &Section = Sections[SectionID];
1302 uint8_t *Target = Section.Address + Offset;
1303 bool RangeOverflow = false;
1304 if (SymType != SymbolRef::ST_Unknown) {
1305 if (AbiVariant != 2) {
1306 // In the ELFv1 ABI, a function call may point to the .opd entry,
1307 // so the final symbol value is calculated based on the relocation
1308 // values in the .opd section.
1309 findOPDEntrySection(Obj, ObjSectionToID, Value);
1311 // In the ELFv2 ABI, a function symbol may provide a local entry
1312 // point, which must be used for direct calls.
1313 uint8_t SymOther = Symbol->getOther();
1314 Value.Addend += ELF::decodePPC64LocalEntryOffset(SymOther);
1316 uint8_t *RelocTarget = Sections[Value.SectionID].Address + Value.Addend;
1317 int32_t delta = static_cast<int32_t>(Target - RelocTarget);
1318 // If it is within 24-bits branch range, just set the branch target
1319 if (SignExtend32<24>(delta) == delta) {
1320 RelocationEntry RE(SectionID, Offset, RelType, Value.Addend);
1321 if (Value.SymbolName)
1322 addRelocationForSymbol(RE, Value.SymbolName);
1324 addRelocationForSection(RE, Value.SectionID);
1326 RangeOverflow = true;
1329 if (SymType == SymbolRef::ST_Unknown || RangeOverflow) {
1330 // It is an external symbol (SymbolRef::ST_Unknown) or within a range
1331 // larger than 24-bits.
1332 StubMap::const_iterator i = Stubs.find(Value);
1333 if (i != Stubs.end()) {
1334 // Symbol function stub already created, just relocate to it
1335 resolveRelocation(Section, Offset,
1336 (uint64_t)Section.Address + i->second, RelType, 0);
1337 DEBUG(dbgs() << " Stub function found\n");
1339 // Create a new stub function.
1340 DEBUG(dbgs() << " Create a new stub function\n");
1341 Stubs[Value] = Section.StubOffset;
1342 uint8_t *StubTargetAddr =
1343 createStubFunction(Section.Address + Section.StubOffset,
1345 RelocationEntry RE(SectionID, StubTargetAddr - Section.Address,
1346 ELF::R_PPC64_ADDR64, Value.Addend);
1348 // Generates the 64-bits address loads as exemplified in section
1349 // 4.5.1 in PPC64 ELF ABI. Note that the relocations need to
1350 // apply to the low part of the instructions, so we have to update
1351 // the offset according to the target endianness.
1352 uint64_t StubRelocOffset = StubTargetAddr - Section.Address;
1353 if (!IsTargetLittleEndian)
1354 StubRelocOffset += 2;
1356 RelocationEntry REhst(SectionID, StubRelocOffset + 0,
1357 ELF::R_PPC64_ADDR16_HIGHEST, Value.Addend);
1358 RelocationEntry REhr(SectionID, StubRelocOffset + 4,
1359 ELF::R_PPC64_ADDR16_HIGHER, Value.Addend);
1360 RelocationEntry REh(SectionID, StubRelocOffset + 12,
1361 ELF::R_PPC64_ADDR16_HI, Value.Addend);
1362 RelocationEntry REl(SectionID, StubRelocOffset + 16,
1363 ELF::R_PPC64_ADDR16_LO, Value.Addend);
1365 if (Value.SymbolName) {
1366 addRelocationForSymbol(REhst, Value.SymbolName);
1367 addRelocationForSymbol(REhr, Value.SymbolName);
1368 addRelocationForSymbol(REh, Value.SymbolName);
1369 addRelocationForSymbol(REl, Value.SymbolName);
1371 addRelocationForSection(REhst, Value.SectionID);
1372 addRelocationForSection(REhr, Value.SectionID);
1373 addRelocationForSection(REh, Value.SectionID);
1374 addRelocationForSection(REl, Value.SectionID);
1377 resolveRelocation(Section, Offset,
1378 (uint64_t)Section.Address + Section.StubOffset,
1380 Section.StubOffset += getMaxStubSize();
1382 if (SymType == SymbolRef::ST_Unknown) {
1383 // Restore the TOC for external calls
1384 if (AbiVariant == 2)
1385 writeInt32BE(Target + 4, 0xE8410018); // ld r2,28(r1)
1387 writeInt32BE(Target + 4, 0xE8410028); // ld r2,40(r1)
1390 } else if (RelType == ELF::R_PPC64_TOC16 ||
1391 RelType == ELF::R_PPC64_TOC16_DS ||
1392 RelType == ELF::R_PPC64_TOC16_LO ||
1393 RelType == ELF::R_PPC64_TOC16_LO_DS ||
1394 RelType == ELF::R_PPC64_TOC16_HI ||
1395 RelType == ELF::R_PPC64_TOC16_HA) {
1396 // These relocations are supposed to subtract the TOC address from
1397 // the final value. This does not fit cleanly into the RuntimeDyld
1398 // scheme, since there may be *two* sections involved in determining
1399 // the relocation value (the section of the symbol refered to by the
1400 // relocation, and the TOC section associated with the current module).
1402 // Fortunately, these relocations are currently only ever generated
1403 // refering to symbols that themselves reside in the TOC, which means
1404 // that the two sections are actually the same. Thus they cancel out
1405 // and we can immediately resolve the relocation right now.
1407 case ELF::R_PPC64_TOC16: RelType = ELF::R_PPC64_ADDR16; break;
1408 case ELF::R_PPC64_TOC16_DS: RelType = ELF::R_PPC64_ADDR16_DS; break;
1409 case ELF::R_PPC64_TOC16_LO: RelType = ELF::R_PPC64_ADDR16_LO; break;
1410 case ELF::R_PPC64_TOC16_LO_DS: RelType = ELF::R_PPC64_ADDR16_LO_DS; break;
1411 case ELF::R_PPC64_TOC16_HI: RelType = ELF::R_PPC64_ADDR16_HI; break;
1412 case ELF::R_PPC64_TOC16_HA: RelType = ELF::R_PPC64_ADDR16_HA; break;
1413 default: llvm_unreachable("Wrong relocation type.");
1416 RelocationValueRef TOCValue;
1417 findPPC64TOCSection(Obj, ObjSectionToID, TOCValue);
1418 if (Value.SymbolName || Value.SectionID != TOCValue.SectionID)
1419 llvm_unreachable("Unsupported TOC relocation.");
1420 Value.Addend -= TOCValue.Addend;
1421 resolveRelocation(Sections[SectionID], Offset, Value.Addend, RelType, 0);
1423 // There are two ways to refer to the TOC address directly: either
1424 // via a ELF::R_PPC64_TOC relocation (where both symbol and addend are
1425 // ignored), or via any relocation that refers to the magic ".TOC."
1426 // symbols (in which case the addend is respected).
1427 if (RelType == ELF::R_PPC64_TOC) {
1428 RelType = ELF::R_PPC64_ADDR64;
1429 findPPC64TOCSection(Obj, ObjSectionToID, Value);
1430 } else if (TargetName == ".TOC.") {
1431 findPPC64TOCSection(Obj, ObjSectionToID, Value);
1432 Value.Addend += Addend;
1435 RelocationEntry RE(SectionID, Offset, RelType, Value.Addend);
1437 if (Value.SymbolName)
1438 addRelocationForSymbol(RE, Value.SymbolName);
1440 addRelocationForSection(RE, Value.SectionID);
1442 } else if (Arch == Triple::systemz &&
1443 (RelType == ELF::R_390_PLT32DBL || RelType == ELF::R_390_GOTENT)) {
1444 // Create function stubs for both PLT and GOT references, regardless of
1445 // whether the GOT reference is to data or code. The stub contains the
1446 // full address of the symbol, as needed by GOT references, and the
1447 // executable part only adds an overhead of 8 bytes.
1449 // We could try to conserve space by allocating the code and data
1450 // parts of the stub separately. However, as things stand, we allocate
1451 // a stub for every relocation, so using a GOT in JIT code should be
1452 // no less space efficient than using an explicit constant pool.
1453 DEBUG(dbgs() << "\t\tThis is a SystemZ indirect relocation.");
1454 SectionEntry &Section = Sections[SectionID];
1456 // Look for an existing stub.
1457 StubMap::const_iterator i = Stubs.find(Value);
1458 uintptr_t StubAddress;
1459 if (i != Stubs.end()) {
1460 StubAddress = uintptr_t(Section.Address) + i->second;
1461 DEBUG(dbgs() << " Stub function found\n");
1463 // Create a new stub function.
1464 DEBUG(dbgs() << " Create a new stub function\n");
1466 uintptr_t BaseAddress = uintptr_t(Section.Address);
1467 uintptr_t StubAlignment = getStubAlignment();
1468 StubAddress = (BaseAddress + Section.StubOffset + StubAlignment - 1) &
1470 unsigned StubOffset = StubAddress - BaseAddress;
1472 Stubs[Value] = StubOffset;
1473 createStubFunction((uint8_t *)StubAddress);
1474 RelocationEntry RE(SectionID, StubOffset + 8, ELF::R_390_64,
1476 if (Value.SymbolName)
1477 addRelocationForSymbol(RE, Value.SymbolName);
1479 addRelocationForSection(RE, Value.SectionID);
1480 Section.StubOffset = StubOffset + getMaxStubSize();
1483 if (RelType == ELF::R_390_GOTENT)
1484 resolveRelocation(Section, Offset, StubAddress + 8, ELF::R_390_PC32DBL,
1487 resolveRelocation(Section, Offset, StubAddress, RelType, Addend);
1488 } else if (Arch == Triple::x86_64) {
1489 if (RelType == ELF::R_X86_64_PLT32) {
1490 // The way the PLT relocations normally work is that the linker allocates
1492 // PLT and this relocation makes a PC-relative call into the PLT. The PLT
1493 // entry will then jump to an address provided by the GOT. On first call,
1495 // GOT address will point back into PLT code that resolves the symbol. After
1496 // the first call, the GOT entry points to the actual function.
1498 // For local functions we're ignoring all of that here and just replacing
1499 // the PLT32 relocation type with PC32, which will translate the relocation
1500 // into a PC-relative call directly to the function. For external symbols we
1501 // can't be sure the function will be within 2^32 bytes of the call site, so
1502 // we need to create a stub, which calls into the GOT. This case is
1503 // equivalent to the usual PLT implementation except that we use the stub
1504 // mechanism in RuntimeDyld (which puts stubs at the end of the section)
1505 // rather than allocating a PLT section.
1506 if (Value.SymbolName) {
1507 // This is a call to an external function.
1508 // Look for an existing stub.
1509 SectionEntry &Section = Sections[SectionID];
1510 StubMap::const_iterator i = Stubs.find(Value);
1511 uintptr_t StubAddress;
1512 if (i != Stubs.end()) {
1513 StubAddress = uintptr_t(Section.Address) + i->second;
1514 DEBUG(dbgs() << " Stub function found\n");
1516 // Create a new stub function (equivalent to a PLT entry).
1517 DEBUG(dbgs() << " Create a new stub function\n");
1519 uintptr_t BaseAddress = uintptr_t(Section.Address);
1520 uintptr_t StubAlignment = getStubAlignment();
1521 StubAddress = (BaseAddress + Section.StubOffset + StubAlignment - 1) &
1523 unsigned StubOffset = StubAddress - BaseAddress;
1524 Stubs[Value] = StubOffset;
1525 createStubFunction((uint8_t *)StubAddress);
1527 // Bump our stub offset counter
1528 Section.StubOffset = StubOffset + getMaxStubSize();
1530 // Allocate a GOT Entry
1531 uint64_t GOTOffset = allocateGOTEntries(SectionID, 1);
1533 // The load of the GOT address has an addend of -4
1534 resolveGOTOffsetRelocation(SectionID, StubOffset + 2, GOTOffset - 4);
1536 // Fill in the value of the symbol we're targeting into the GOT
1537 addRelocationForSymbol(computeGOTOffsetRE(SectionID,GOTOffset,0,ELF::R_X86_64_64),
1541 // Make the target call a call into the stub table.
1542 resolveRelocation(Section, Offset, StubAddress, ELF::R_X86_64_PC32,
1545 RelocationEntry RE(SectionID, Offset, ELF::R_X86_64_PC32, Value.Addend,
1547 addRelocationForSection(RE, Value.SectionID);
1549 } else if (RelType == ELF::R_X86_64_GOTPCREL) {
1550 uint64_t GOTOffset = allocateGOTEntries(SectionID, 1);
1551 resolveGOTOffsetRelocation(SectionID, Offset, GOTOffset + Addend);
1553 // Fill in the value of the symbol we're targeting into the GOT
1554 RelocationEntry RE = computeGOTOffsetRE(SectionID, GOTOffset, Value.Offset, ELF::R_X86_64_64);
1555 if (Value.SymbolName)
1556 addRelocationForSymbol(RE, Value.SymbolName);
1558 addRelocationForSection(RE, Value.SectionID);
1559 } else if (RelType == ELF::R_X86_64_PC32) {
1560 Value.Addend += support::ulittle32_t::ref(computePlaceholderAddress(SectionID, Offset));
1561 processSimpleRelocation(SectionID, Offset, RelType, Value);
1562 } else if (RelType == ELF::R_X86_64_PC64) {
1563 Value.Addend += support::ulittle64_t::ref(computePlaceholderAddress(SectionID, Offset));
1564 processSimpleRelocation(SectionID, Offset, RelType, Value);
1566 processSimpleRelocation(SectionID, Offset, RelType, Value);
1569 if (Arch == Triple::x86) {
1570 Value.Addend += support::ulittle32_t::ref(computePlaceholderAddress(SectionID, Offset));
1572 processSimpleRelocation(SectionID, Offset, RelType, Value);
1577 size_t RuntimeDyldELF::getGOTEntrySize() {
1578 // We don't use the GOT in all of these cases, but it's essentially free
1579 // to put them all here.
1582 case Triple::x86_64:
1583 case Triple::aarch64:
1584 case Triple::aarch64_be:
1586 case Triple::ppc64le:
1587 case Triple::systemz:
1588 Result = sizeof(uint64_t);
1593 Result = sizeof(uint32_t);
1596 case Triple::mipsel:
1597 case Triple::mips64:
1598 case Triple::mips64el:
1600 Result = sizeof(uint32_t);
1601 else if (IsMipsN64ABI)
1602 Result = sizeof(uint64_t);
1604 llvm_unreachable("Mips ABI not handled");
1607 llvm_unreachable("Unsupported CPU type!");
1612 uint64_t RuntimeDyldELF::allocateGOTEntries(unsigned SectionID, unsigned no)
1614 (void)SectionID; // The GOT Section is the same for all section in the object file
1615 if (GOTSectionID == 0) {
1616 GOTSectionID = Sections.size();
1617 // Reserve a section id. We'll allocate the section later
1618 // once we know the total size
1619 Sections.push_back(SectionEntry(".got", 0, 0, 0));
1621 uint64_t StartOffset = CurrentGOTIndex * getGOTEntrySize();
1622 CurrentGOTIndex += no;
1626 void RuntimeDyldELF::resolveGOTOffsetRelocation(unsigned SectionID, uint64_t Offset, uint64_t GOTOffset)
1628 // Fill in the relative address of the GOT Entry into the stub
1629 RelocationEntry GOTRE(SectionID, Offset, ELF::R_X86_64_PC32, GOTOffset);
1630 addRelocationForSection(GOTRE, GOTSectionID);
1633 RelocationEntry RuntimeDyldELF::computeGOTOffsetRE(unsigned SectionID, uint64_t GOTOffset, uint64_t SymbolOffset,
1636 (void)SectionID; // The GOT Section is the same for all section in the object file
1637 return RelocationEntry(GOTSectionID, GOTOffset, Type, SymbolOffset);
1640 void RuntimeDyldELF::finalizeLoad(const ObjectFile &Obj,
1641 ObjSectionToIDMap &SectionMap) {
1642 // If necessary, allocate the global offset table
1643 if (GOTSectionID != 0) {
1644 // Allocate memory for the section
1645 size_t TotalSize = CurrentGOTIndex * getGOTEntrySize();
1646 uint8_t *Addr = MemMgr.allocateDataSection(TotalSize, getGOTEntrySize(),
1647 GOTSectionID, ".got", false);
1649 report_fatal_error("Unable to allocate memory for GOT!");
1651 Sections[GOTSectionID] = SectionEntry(".got", Addr, TotalSize, 0);
1654 Checker->registerSection(Obj.getFileName(), GOTSectionID);
1656 // For now, initialize all GOT entries to zero. We'll fill them in as
1657 // needed when GOT-based relocations are applied.
1658 memset(Addr, 0, TotalSize);
1660 // To correctly resolve Mips GOT relocations, we need a mapping from
1661 // object's sections to GOTs.
1662 for (section_iterator SI = Obj.section_begin(), SE = Obj.section_end();
1664 if (SI->relocation_begin() != SI->relocation_end()) {
1665 section_iterator RelocatedSection = SI->getRelocatedSection();
1666 ObjSectionToIDMap::iterator i = SectionMap.find(*RelocatedSection);
1667 assert (i != SectionMap.end());
1668 SectionToGOTMap[i->second] = GOTSectionID;
1671 GOTSymbolOffsets.clear();
1675 // Look for and record the EH frame section.
1676 ObjSectionToIDMap::iterator i, e;
1677 for (i = SectionMap.begin(), e = SectionMap.end(); i != e; ++i) {
1678 const SectionRef &Section = i->first;
1680 Section.getName(Name);
1681 if (Name == ".eh_frame") {
1682 UnregisteredEHFrameSections.push_back(i->second);
1688 CurrentGOTIndex = 0;
1691 bool RuntimeDyldELF::isCompatibleFile(const object::ObjectFile &Obj) const {