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 "llvm/ADT/IntervalMap.h"
16 #include "llvm/ADT/STLExtras.h"
17 #include "llvm/ADT/StringRef.h"
18 #include "llvm/ADT/Triple.h"
19 #include "llvm/MC/MCStreamer.h"
20 #include "llvm/Object/ELFObjectFile.h"
21 #include "llvm/Object/ObjectFile.h"
22 #include "llvm/Support/ELF.h"
23 #include "llvm/Support/Endian.h"
24 #include "llvm/Support/MemoryBuffer.h"
25 #include "llvm/Support/TargetRegistry.h"
28 using namespace llvm::object;
30 #define DEBUG_TYPE "dyld"
32 static inline std::error_code check(std::error_code Err) {
34 report_fatal_error(Err.message());
41 template <class ELFT> class DyldELFObject : public ELFObjectFile<ELFT> {
42 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT)
44 typedef Elf_Shdr_Impl<ELFT> Elf_Shdr;
45 typedef Elf_Sym_Impl<ELFT> Elf_Sym;
46 typedef Elf_Rel_Impl<ELFT, false> Elf_Rel;
47 typedef Elf_Rel_Impl<ELFT, true> Elf_Rela;
49 typedef Elf_Ehdr_Impl<ELFT> Elf_Ehdr;
51 typedef typename ELFDataTypeTypedefHelper<ELFT>::value_type addr_type;
54 DyldELFObject(MemoryBufferRef Wrapper, std::error_code &ec);
56 void updateSectionAddress(const SectionRef &Sec, uint64_t Addr);
58 void updateSymbolAddress(const SymbolRef &SymRef, uint64_t Addr);
60 // Methods for type inquiry through isa, cast and dyn_cast
61 static inline bool classof(const Binary *v) {
62 return (isa<ELFObjectFile<ELFT>>(v) &&
63 classof(cast<ELFObjectFile<ELFT>>(v)));
65 static inline bool classof(const ELFObjectFile<ELFT> *v) {
66 return v->isDyldType();
73 // The MemoryBuffer passed into this constructor is just a wrapper around the
74 // actual memory. Ultimately, the Binary parent class will take ownership of
75 // this MemoryBuffer object but not the underlying memory.
77 DyldELFObject<ELFT>::DyldELFObject(MemoryBufferRef Wrapper, std::error_code &EC)
78 : ELFObjectFile<ELFT>(Wrapper, EC) {
79 this->isDyldELFObject = true;
83 void DyldELFObject<ELFT>::updateSectionAddress(const SectionRef &Sec,
85 DataRefImpl ShdrRef = Sec.getRawDataRefImpl();
87 const_cast<Elf_Shdr *>(reinterpret_cast<const Elf_Shdr *>(ShdrRef.p));
89 // This assumes the address passed in matches the target address bitness
90 // The template-based type cast handles everything else.
91 shdr->sh_addr = static_cast<addr_type>(Addr);
95 void DyldELFObject<ELFT>::updateSymbolAddress(const SymbolRef &SymRef,
98 Elf_Sym *sym = const_cast<Elf_Sym *>(
99 ELFObjectFile<ELFT>::getSymbol(SymRef.getRawDataRefImpl()));
101 // This assumes the address passed in matches the target address bitness
102 // The template-based type cast handles everything else.
103 sym->st_value = static_cast<addr_type>(Addr);
106 class LoadedELFObjectInfo : public RuntimeDyld::LoadedObjectInfo {
108 LoadedELFObjectInfo(RuntimeDyldImpl &RTDyld, unsigned BeginIdx,
110 : RuntimeDyld::LoadedObjectInfo(RTDyld, BeginIdx, EndIdx) {}
112 OwningBinary<ObjectFile>
113 getObjectForDebug(const ObjectFile &Obj) const override;
116 template <typename ELFT>
117 std::unique_ptr<DyldELFObject<ELFT>>
118 createRTDyldELFObject(MemoryBufferRef Buffer,
119 const LoadedELFObjectInfo &L,
120 std::error_code &ec) {
121 typedef typename ELFFile<ELFT>::Elf_Shdr Elf_Shdr;
122 typedef typename ELFDataTypeTypedefHelper<ELFT>::value_type addr_type;
124 std::unique_ptr<DyldELFObject<ELFT>> Obj =
125 llvm::make_unique<DyldELFObject<ELFT>>(Buffer, ec);
127 // Iterate over all sections in the object.
128 for (const auto &Sec : Obj->sections()) {
129 StringRef SectionName;
130 Sec.getName(SectionName);
131 if (SectionName != "") {
132 DataRefImpl ShdrRef = Sec.getRawDataRefImpl();
133 Elf_Shdr *shdr = const_cast<Elf_Shdr *>(
134 reinterpret_cast<const Elf_Shdr *>(ShdrRef.p));
136 if (uint64_t SecLoadAddr = L.getSectionLoadAddress(SectionName)) {
137 // This assumes that the address passed in matches the target address
138 // bitness. The template-based type cast handles everything else.
139 shdr->sh_addr = static_cast<addr_type>(SecLoadAddr);
147 OwningBinary<ObjectFile> createELFDebugObject(const ObjectFile &Obj,
148 const LoadedELFObjectInfo &L) {
149 assert(Obj.isELF() && "Not an ELF object file.");
151 std::unique_ptr<MemoryBuffer> Buffer =
152 MemoryBuffer::getMemBufferCopy(Obj.getData(), Obj.getFileName());
156 std::unique_ptr<ObjectFile> DebugObj;
157 if (Obj.getBytesInAddress() == 4 && Obj.isLittleEndian()) {
158 typedef ELFType<support::little, 2, false> ELF32LE;
159 DebugObj = createRTDyldELFObject<ELF32LE>(Buffer->getMemBufferRef(), L, ec);
160 } else if (Obj.getBytesInAddress() == 4 && !Obj.isLittleEndian()) {
161 typedef ELFType<support::big, 2, false> ELF32BE;
162 DebugObj = createRTDyldELFObject<ELF32BE>(Buffer->getMemBufferRef(), L, ec);
163 } else if (Obj.getBytesInAddress() == 8 && !Obj.isLittleEndian()) {
164 typedef ELFType<support::big, 2, true> ELF64BE;
165 DebugObj = createRTDyldELFObject<ELF64BE>(Buffer->getMemBufferRef(), L, ec);
166 } else if (Obj.getBytesInAddress() == 8 && Obj.isLittleEndian()) {
167 typedef ELFType<support::little, 2, true> ELF64LE;
168 DebugObj = createRTDyldELFObject<ELF64LE>(Buffer->getMemBufferRef(), L, ec);
170 llvm_unreachable("Unexpected ELF format");
172 assert(!ec && "Could not construct copy ELF object file");
174 return OwningBinary<ObjectFile>(std::move(DebugObj), std::move(Buffer));
177 OwningBinary<ObjectFile>
178 LoadedELFObjectInfo::getObjectForDebug(const ObjectFile &Obj) const {
179 return createELFDebugObject(Obj, *this);
186 RuntimeDyldELF::RuntimeDyldELF(RTDyldMemoryManager *mm) : RuntimeDyldImpl(mm) {}
187 RuntimeDyldELF::~RuntimeDyldELF() {}
189 void RuntimeDyldELF::registerEHFrames() {
192 for (int i = 0, e = UnregisteredEHFrameSections.size(); i != e; ++i) {
193 SID EHFrameSID = UnregisteredEHFrameSections[i];
194 uint8_t *EHFrameAddr = Sections[EHFrameSID].Address;
195 uint64_t EHFrameLoadAddr = Sections[EHFrameSID].LoadAddress;
196 size_t EHFrameSize = Sections[EHFrameSID].Size;
197 MemMgr->registerEHFrames(EHFrameAddr, EHFrameLoadAddr, EHFrameSize);
198 RegisteredEHFrameSections.push_back(EHFrameSID);
200 UnregisteredEHFrameSections.clear();
203 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_GOTPCREL: {
251 // findGOTEntry returns the 'G + GOT' part of the relocation calculation
252 // based on the load/target address of the GOT (not the current/local addr).
253 uint64_t GOTAddr = findGOTEntry(Value, SymOffset);
254 uint64_t FinalAddress = Section.LoadAddress + Offset;
255 // The processRelocationRef method combines the symbol offset and the addend
256 // and in most cases that's what we want. For this relocation type, we need
257 // the raw addend, so we subtract the symbol offset to get it.
258 int64_t RealOffset = GOTAddr + Addend - SymOffset - FinalAddress;
259 assert(RealOffset <= INT32_MAX && RealOffset >= INT32_MIN);
260 int32_t TruncOffset = (RealOffset & 0xFFFFFFFF);
261 support::ulittle32_t::ref(Section.Address + Offset) = TruncOffset;
264 case ELF::R_X86_64_PC32: {
265 // Get the placeholder value from the generated object since
266 // a previous relocation attempt may have overwritten the loaded version
267 support::ulittle32_t::ref Placeholder(
268 (void *)(Section.ObjAddress + Offset));
269 uint64_t FinalAddress = Section.LoadAddress + Offset;
270 int64_t RealOffset = Placeholder + Value + Addend - FinalAddress;
271 assert(RealOffset <= INT32_MAX && RealOffset >= INT32_MIN);
272 int32_t TruncOffset = (RealOffset & 0xFFFFFFFF);
273 support::ulittle32_t::ref(Section.Address + Offset) = TruncOffset;
276 case ELF::R_X86_64_PC64: {
277 // Get the placeholder value from the generated object since
278 // a previous relocation attempt may have overwritten the loaded version
279 support::ulittle64_t::ref Placeholder(
280 (void *)(Section.ObjAddress + Offset));
281 uint64_t FinalAddress = Section.LoadAddress + Offset;
282 support::ulittle64_t::ref(Section.Address + Offset) =
283 Placeholder + Value + Addend - FinalAddress;
289 void RuntimeDyldELF::resolveX86Relocation(const SectionEntry &Section,
290 uint64_t Offset, uint32_t Value,
291 uint32_t Type, int32_t Addend) {
293 case ELF::R_386_32: {
294 // Get the placeholder value from the generated object since
295 // a previous relocation attempt may have overwritten the loaded version
296 support::ulittle32_t::ref Placeholder(
297 (void *)(Section.ObjAddress + Offset));
298 support::ulittle32_t::ref(Section.Address + Offset) =
299 Placeholder + Value + Addend;
302 case ELF::R_386_PC32: {
303 // Get the placeholder value from the generated object since
304 // a previous relocation attempt may have overwritten the loaded version
305 support::ulittle32_t::ref Placeholder(
306 (void *)(Section.ObjAddress + Offset));
307 uint32_t FinalAddress = ((Section.LoadAddress + Offset) & 0xFFFFFFFF);
308 uint32_t RealOffset = Placeholder + Value + Addend - FinalAddress;
309 support::ulittle32_t::ref(Section.Address + Offset) = RealOffset;
313 // There are other relocation types, but it appears these are the
314 // only ones currently used by the LLVM ELF object writer
315 llvm_unreachable("Relocation type not implemented yet!");
320 void RuntimeDyldELF::resolveAArch64Relocation(const SectionEntry &Section,
321 uint64_t Offset, uint64_t Value,
322 uint32_t Type, int64_t Addend) {
323 uint32_t *TargetPtr = reinterpret_cast<uint32_t *>(Section.Address + Offset);
324 uint64_t FinalAddress = Section.LoadAddress + Offset;
326 DEBUG(dbgs() << "resolveAArch64Relocation, LocalAddress: 0x"
327 << format("%llx", Section.Address + Offset)
328 << " FinalAddress: 0x" << format("%llx", FinalAddress)
329 << " Value: 0x" << format("%llx", Value) << " Type: 0x"
330 << format("%x", Type) << " Addend: 0x" << format("%llx", Addend)
335 llvm_unreachable("Relocation type not implemented yet!");
337 case ELF::R_AARCH64_ABS64: {
338 uint64_t *TargetPtr =
339 reinterpret_cast<uint64_t *>(Section.Address + Offset);
340 *TargetPtr = Value + Addend;
343 case ELF::R_AARCH64_PREL32: {
344 uint64_t Result = Value + Addend - FinalAddress;
345 assert(static_cast<int64_t>(Result) >= INT32_MIN &&
346 static_cast<int64_t>(Result) <= UINT32_MAX);
347 *TargetPtr = static_cast<uint32_t>(Result & 0xffffffffU);
350 case ELF::R_AARCH64_CALL26: // fallthrough
351 case ELF::R_AARCH64_JUMP26: {
352 // Operation: S+A-P. Set Call or B immediate value to bits fff_fffc of the
354 uint64_t BranchImm = Value + Addend - FinalAddress;
356 // "Check that -2^27 <= result < 2^27".
357 assert(-(1LL << 27) <= static_cast<int64_t>(BranchImm) &&
358 static_cast<int64_t>(BranchImm) < (1LL << 27));
360 // AArch64 code is emitted with .rela relocations. The data already in any
361 // bits affected by the relocation on entry is garbage.
362 *TargetPtr &= 0xfc000000U;
363 // Immediate goes in bits 25:0 of B and BL.
364 *TargetPtr |= static_cast<uint32_t>(BranchImm & 0xffffffcU) >> 2;
367 case ELF::R_AARCH64_MOVW_UABS_G3: {
368 uint64_t Result = Value + Addend;
370 // AArch64 code is emitted with .rela relocations. The data already in any
371 // bits affected by the relocation on entry is garbage.
372 *TargetPtr &= 0xffe0001fU;
373 // Immediate goes in bits 20:5 of MOVZ/MOVK instruction
374 *TargetPtr |= Result >> (48 - 5);
375 // Shift must be "lsl #48", in bits 22:21
376 assert((*TargetPtr >> 21 & 0x3) == 3 && "invalid shift for relocation");
379 case ELF::R_AARCH64_MOVW_UABS_G2_NC: {
380 uint64_t Result = Value + Addend;
382 // AArch64 code is emitted with .rela relocations. The data already in any
383 // bits affected by the relocation on entry is garbage.
384 *TargetPtr &= 0xffe0001fU;
385 // Immediate goes in bits 20:5 of MOVZ/MOVK instruction
386 *TargetPtr |= ((Result & 0xffff00000000ULL) >> (32 - 5));
387 // Shift must be "lsl #32", in bits 22:21
388 assert((*TargetPtr >> 21 & 0x3) == 2 && "invalid shift for relocation");
391 case ELF::R_AARCH64_MOVW_UABS_G1_NC: {
392 uint64_t Result = Value + Addend;
394 // AArch64 code is emitted with .rela relocations. The data already in any
395 // bits affected by the relocation on entry is garbage.
396 *TargetPtr &= 0xffe0001fU;
397 // Immediate goes in bits 20:5 of MOVZ/MOVK instruction
398 *TargetPtr |= ((Result & 0xffff0000U) >> (16 - 5));
399 // Shift must be "lsl #16", in bits 22:2
400 assert((*TargetPtr >> 21 & 0x3) == 1 && "invalid shift for relocation");
403 case ELF::R_AARCH64_MOVW_UABS_G0_NC: {
404 uint64_t Result = Value + Addend;
406 // AArch64 code is emitted with .rela relocations. The data already in any
407 // bits affected by the relocation on entry is garbage.
408 *TargetPtr &= 0xffe0001fU;
409 // Immediate goes in bits 20:5 of MOVZ/MOVK instruction
410 *TargetPtr |= ((Result & 0xffffU) << 5);
411 // Shift must be "lsl #0", in bits 22:21.
412 assert((*TargetPtr >> 21 & 0x3) == 0 && "invalid shift for relocation");
415 case ELF::R_AARCH64_ADR_PREL_PG_HI21: {
416 // Operation: Page(S+A) - Page(P)
418 ((Value + Addend) & ~0xfffULL) - (FinalAddress & ~0xfffULL);
420 // Check that -2^32 <= X < 2^32
421 assert(static_cast<int64_t>(Result) >= (-1LL << 32) &&
422 static_cast<int64_t>(Result) < (1LL << 32) &&
423 "overflow check failed for relocation");
425 // AArch64 code is emitted with .rela relocations. The data already in any
426 // bits affected by the relocation on entry is garbage.
427 *TargetPtr &= 0x9f00001fU;
428 // Immediate goes in bits 30:29 + 5:23 of ADRP instruction, taken
429 // from bits 32:12 of X.
430 *TargetPtr |= ((Result & 0x3000U) << (29 - 12));
431 *TargetPtr |= ((Result & 0x1ffffc000ULL) >> (14 - 5));
434 case ELF::R_AARCH64_LDST32_ABS_LO12_NC: {
436 uint64_t Result = Value + Addend;
438 // AArch64 code is emitted with .rela relocations. The data already in any
439 // bits affected by the relocation on entry is garbage.
440 *TargetPtr &= 0xffc003ffU;
441 // Immediate goes in bits 21:10 of LD/ST instruction, taken
442 // from bits 11:2 of X
443 *TargetPtr |= ((Result & 0xffc) << (10 - 2));
446 case ELF::R_AARCH64_LDST64_ABS_LO12_NC: {
448 uint64_t Result = Value + Addend;
450 // AArch64 code is emitted with .rela relocations. The data already in any
451 // bits affected by the relocation on entry is garbage.
452 *TargetPtr &= 0xffc003ffU;
453 // Immediate goes in bits 21:10 of LD/ST instruction, taken
454 // from bits 11:3 of X
455 *TargetPtr |= ((Result & 0xff8) << (10 - 3));
461 void RuntimeDyldELF::resolveARMRelocation(const SectionEntry &Section,
462 uint64_t Offset, uint32_t Value,
463 uint32_t Type, int32_t Addend) {
464 // TODO: Add Thumb relocations.
465 uint32_t *Placeholder =
466 reinterpret_cast<uint32_t *>(Section.ObjAddress + Offset);
467 uint32_t *TargetPtr = (uint32_t *)(Section.Address + Offset);
468 uint32_t FinalAddress = ((Section.LoadAddress + Offset) & 0xFFFFFFFF);
471 DEBUG(dbgs() << "resolveARMRelocation, LocalAddress: "
472 << Section.Address + Offset
473 << " FinalAddress: " << format("%p", FinalAddress) << " Value: "
474 << format("%x", Value) << " Type: " << format("%x", Type)
475 << " Addend: " << format("%x", Addend) << "\n");
479 llvm_unreachable("Not implemented relocation type!");
481 case ELF::R_ARM_NONE:
483 // Write a 32bit value to relocation address, taking into account the
484 // implicit addend encoded in the target.
485 case ELF::R_ARM_PREL31:
486 case ELF::R_ARM_TARGET1:
487 case ELF::R_ARM_ABS32:
488 *TargetPtr = *Placeholder + Value;
490 // Write first 16 bit of 32 bit value to the mov instruction.
491 // Last 4 bit should be shifted.
492 case ELF::R_ARM_MOVW_ABS_NC:
493 // We are not expecting any other addend in the relocation address.
494 // Using 0x000F0FFF because MOVW has its 16 bit immediate split into 2
495 // non-contiguous fields.
496 assert((*Placeholder & 0x000F0FFF) == 0);
497 Value = Value & 0xFFFF;
498 *TargetPtr = *Placeholder | (Value & 0xFFF);
499 *TargetPtr |= ((Value >> 12) & 0xF) << 16;
501 // Write last 16 bit of 32 bit value to the mov instruction.
502 // Last 4 bit should be shifted.
503 case ELF::R_ARM_MOVT_ABS:
504 // We are not expecting any other addend in the relocation address.
505 // Use 0x000F0FFF for the same reason as R_ARM_MOVW_ABS_NC.
506 assert((*Placeholder & 0x000F0FFF) == 0);
508 Value = (Value >> 16) & 0xFFFF;
509 *TargetPtr = *Placeholder | (Value & 0xFFF);
510 *TargetPtr |= ((Value >> 12) & 0xF) << 16;
512 // Write 24 bit relative value to the branch instruction.
513 case ELF::R_ARM_PC24: // Fall through.
514 case ELF::R_ARM_CALL: // Fall through.
515 case ELF::R_ARM_JUMP24: {
516 int32_t RelValue = static_cast<int32_t>(Value - FinalAddress - 8);
517 RelValue = (RelValue & 0x03FFFFFC) >> 2;
518 assert((*TargetPtr & 0xFFFFFF) == 0xFFFFFE);
519 *TargetPtr &= 0xFF000000;
520 *TargetPtr |= RelValue;
523 case ELF::R_ARM_PRIVATE_0:
524 // This relocation is reserved by the ARM ELF ABI for internal use. We
525 // appropriate it here to act as an R_ARM_ABS32 without any addend for use
526 // in the stubs created during JIT (which can't put an addend into the
527 // original object file).
533 void RuntimeDyldELF::resolveMIPSRelocation(const SectionEntry &Section,
534 uint64_t Offset, uint32_t Value,
535 uint32_t Type, int32_t Addend) {
536 uint32_t *Placeholder =
537 reinterpret_cast<uint32_t *>(Section.ObjAddress + Offset);
538 uint32_t *TargetPtr = (uint32_t *)(Section.Address + Offset);
541 DEBUG(dbgs() << "resolveMipselocation, LocalAddress: "
542 << Section.Address + Offset << " FinalAddress: "
543 << format("%p", Section.LoadAddress + Offset) << " Value: "
544 << format("%x", Value) << " Type: " << format("%x", Type)
545 << " Addend: " << format("%x", Addend) << "\n");
549 llvm_unreachable("Not implemented relocation type!");
552 *TargetPtr = Value + (*Placeholder);
555 *TargetPtr = ((*Placeholder) & 0xfc000000) | ((Value & 0x0fffffff) >> 2);
557 case ELF::R_MIPS_HI16:
558 // Get the higher 16-bits. Also add 1 if bit 15 is 1.
559 Value += ((*Placeholder) & 0x0000ffff) << 16;
561 ((*Placeholder) & 0xffff0000) | (((Value + 0x8000) >> 16) & 0xffff);
563 case ELF::R_MIPS_LO16:
564 Value += ((*Placeholder) & 0x0000ffff);
565 *TargetPtr = ((*Placeholder) & 0xffff0000) | (Value & 0xffff);
567 case ELF::R_MIPS_UNUSED1:
568 // Similar to ELF::R_ARM_PRIVATE_0, R_MIPS_UNUSED1 and R_MIPS_UNUSED2
569 // are used for internal JIT purpose. These relocations are similar to
570 // R_MIPS_HI16 and R_MIPS_LO16, but they do not take any addend into
573 ((*TargetPtr) & 0xffff0000) | (((Value + 0x8000) >> 16) & 0xffff);
575 case ELF::R_MIPS_UNUSED2:
576 *TargetPtr = ((*TargetPtr) & 0xffff0000) | (Value & 0xffff);
581 // Return the .TOC. section and offset.
582 void RuntimeDyldELF::findPPC64TOCSection(const ObjectFile &Obj,
583 ObjSectionToIDMap &LocalSections,
584 RelocationValueRef &Rel) {
585 // Set a default SectionID in case we do not find a TOC section below.
586 // This may happen for references to TOC base base (sym@toc, .odp
587 // relocation) without a .toc directive. In this case just use the
588 // first section (which is usually the .odp) since the code won't
589 // reference the .toc base directly.
590 Rel.SymbolName = NULL;
593 // The TOC consists of sections .got, .toc, .tocbss, .plt in that
594 // order. The TOC starts where the first of these sections starts.
595 for (section_iterator si = Obj.section_begin(), se = Obj.section_end();
598 StringRef SectionName;
599 check(si->getName(SectionName));
601 if (SectionName == ".got"
602 || SectionName == ".toc"
603 || SectionName == ".tocbss"
604 || SectionName == ".plt") {
605 Rel.SectionID = findOrEmitSection(Obj, *si, false, LocalSections);
610 // Per the ppc64-elf-linux ABI, The TOC base is TOC value plus 0x8000
611 // thus permitting a full 64 Kbytes segment.
615 // Returns the sections and offset associated with the ODP entry referenced
617 void RuntimeDyldELF::findOPDEntrySection(const ObjectFile &Obj,
618 ObjSectionToIDMap &LocalSections,
619 RelocationValueRef &Rel) {
620 // Get the ELF symbol value (st_value) to compare with Relocation offset in
622 for (section_iterator si = Obj.section_begin(), se = Obj.section_end();
624 section_iterator RelSecI = si->getRelocatedSection();
625 if (RelSecI == Obj.section_end())
628 StringRef RelSectionName;
629 check(RelSecI->getName(RelSectionName));
630 if (RelSectionName != ".opd")
633 for (relocation_iterator i = si->relocation_begin(),
634 e = si->relocation_end();
636 // The R_PPC64_ADDR64 relocation indicates the first field
639 check(i->getType(TypeFunc));
640 if (TypeFunc != ELF::R_PPC64_ADDR64) {
645 uint64_t TargetSymbolOffset;
646 symbol_iterator TargetSymbol = i->getSymbol();
647 check(i->getOffset(TargetSymbolOffset));
649 check(getELFRelocationAddend(*i, Addend));
655 // Just check if following relocation is a R_PPC64_TOC
657 check(i->getType(TypeTOC));
658 if (TypeTOC != ELF::R_PPC64_TOC)
661 // Finally compares the Symbol value and the target symbol offset
662 // to check if this .opd entry refers to the symbol the relocation
664 if (Rel.Addend != (int64_t)TargetSymbolOffset)
667 section_iterator tsi(Obj.section_end());
668 check(TargetSymbol->getSection(tsi));
669 bool IsCode = tsi->isText();
670 Rel.SectionID = findOrEmitSection(Obj, (*tsi), IsCode, LocalSections);
671 Rel.Addend = (intptr_t)Addend;
675 llvm_unreachable("Attempting to get address of ODP entry!");
678 // Relocation masks following the #lo(value), #hi(value), #ha(value),
679 // #higher(value), #highera(value), #highest(value), and #highesta(value)
680 // macros defined in section 4.5.1. Relocation Types of the PPC-elf64abi
683 static inline uint16_t applyPPClo(uint64_t value) { return value & 0xffff; }
685 static inline uint16_t applyPPChi(uint64_t value) {
686 return (value >> 16) & 0xffff;
689 static inline uint16_t applyPPCha (uint64_t value) {
690 return ((value + 0x8000) >> 16) & 0xffff;
693 static inline uint16_t applyPPChigher(uint64_t value) {
694 return (value >> 32) & 0xffff;
697 static inline uint16_t applyPPChighera (uint64_t value) {
698 return ((value + 0x8000) >> 32) & 0xffff;
701 static inline uint16_t applyPPChighest(uint64_t value) {
702 return (value >> 48) & 0xffff;
705 static inline uint16_t applyPPChighesta (uint64_t value) {
706 return ((value + 0x8000) >> 48) & 0xffff;
709 void RuntimeDyldELF::resolvePPC64Relocation(const SectionEntry &Section,
710 uint64_t Offset, uint64_t Value,
711 uint32_t Type, int64_t Addend) {
712 uint8_t *LocalAddress = Section.Address + Offset;
715 llvm_unreachable("Relocation type not implemented yet!");
717 case ELF::R_PPC64_ADDR16:
718 writeInt16BE(LocalAddress, applyPPClo(Value + Addend));
720 case ELF::R_PPC64_ADDR16_DS:
721 writeInt16BE(LocalAddress, applyPPClo(Value + Addend) & ~3);
723 case ELF::R_PPC64_ADDR16_LO:
724 writeInt16BE(LocalAddress, applyPPClo(Value + Addend));
726 case ELF::R_PPC64_ADDR16_LO_DS:
727 writeInt16BE(LocalAddress, applyPPClo(Value + Addend) & ~3);
729 case ELF::R_PPC64_ADDR16_HI:
730 writeInt16BE(LocalAddress, applyPPChi(Value + Addend));
732 case ELF::R_PPC64_ADDR16_HA:
733 writeInt16BE(LocalAddress, applyPPCha(Value + Addend));
735 case ELF::R_PPC64_ADDR16_HIGHER:
736 writeInt16BE(LocalAddress, applyPPChigher(Value + Addend));
738 case ELF::R_PPC64_ADDR16_HIGHERA:
739 writeInt16BE(LocalAddress, applyPPChighera(Value + Addend));
741 case ELF::R_PPC64_ADDR16_HIGHEST:
742 writeInt16BE(LocalAddress, applyPPChighest(Value + Addend));
744 case ELF::R_PPC64_ADDR16_HIGHESTA:
745 writeInt16BE(LocalAddress, applyPPChighesta(Value + Addend));
747 case ELF::R_PPC64_ADDR14: {
748 assert(((Value + Addend) & 3) == 0);
749 // Preserve the AA/LK bits in the branch instruction
750 uint8_t aalk = *(LocalAddress + 3);
751 writeInt16BE(LocalAddress + 2, (aalk & 3) | ((Value + Addend) & 0xfffc));
753 case ELF::R_PPC64_REL16_LO: {
754 uint64_t FinalAddress = (Section.LoadAddress + Offset);
755 uint64_t Delta = Value - FinalAddress + Addend;
756 writeInt16BE(LocalAddress, applyPPClo(Delta));
758 case ELF::R_PPC64_REL16_HI: {
759 uint64_t FinalAddress = (Section.LoadAddress + Offset);
760 uint64_t Delta = Value - FinalAddress + Addend;
761 writeInt16BE(LocalAddress, applyPPChi(Delta));
763 case ELF::R_PPC64_REL16_HA: {
764 uint64_t FinalAddress = (Section.LoadAddress + Offset);
765 uint64_t Delta = Value - FinalAddress + Addend;
766 writeInt16BE(LocalAddress, applyPPCha(Delta));
768 case ELF::R_PPC64_ADDR32: {
769 int32_t Result = static_cast<int32_t>(Value + Addend);
770 if (SignExtend32<32>(Result) != Result)
771 llvm_unreachable("Relocation R_PPC64_ADDR32 overflow");
772 writeInt32BE(LocalAddress, Result);
774 case ELF::R_PPC64_REL24: {
775 uint64_t FinalAddress = (Section.LoadAddress + Offset);
776 int32_t delta = static_cast<int32_t>(Value - FinalAddress + Addend);
777 if (SignExtend32<24>(delta) != delta)
778 llvm_unreachable("Relocation R_PPC64_REL24 overflow");
779 // Generates a 'bl <address>' instruction
780 writeInt32BE(LocalAddress, 0x48000001 | (delta & 0x03FFFFFC));
782 case ELF::R_PPC64_REL32: {
783 uint64_t FinalAddress = (Section.LoadAddress + Offset);
784 int32_t delta = static_cast<int32_t>(Value - FinalAddress + Addend);
785 if (SignExtend32<32>(delta) != delta)
786 llvm_unreachable("Relocation R_PPC64_REL32 overflow");
787 writeInt32BE(LocalAddress, delta);
789 case ELF::R_PPC64_REL64: {
790 uint64_t FinalAddress = (Section.LoadAddress + Offset);
791 uint64_t Delta = Value - FinalAddress + Addend;
792 writeInt64BE(LocalAddress, Delta);
794 case ELF::R_PPC64_ADDR64:
795 writeInt64BE(LocalAddress, Value + Addend);
800 void RuntimeDyldELF::resolveSystemZRelocation(const SectionEntry &Section,
801 uint64_t Offset, uint64_t Value,
802 uint32_t Type, int64_t Addend) {
803 uint8_t *LocalAddress = Section.Address + Offset;
806 llvm_unreachable("Relocation type not implemented yet!");
808 case ELF::R_390_PC16DBL:
809 case ELF::R_390_PLT16DBL: {
810 int64_t Delta = (Value + Addend) - (Section.LoadAddress + Offset);
811 assert(int16_t(Delta / 2) * 2 == Delta && "R_390_PC16DBL overflow");
812 writeInt16BE(LocalAddress, Delta / 2);
815 case ELF::R_390_PC32DBL:
816 case ELF::R_390_PLT32DBL: {
817 int64_t Delta = (Value + Addend) - (Section.LoadAddress + Offset);
818 assert(int32_t(Delta / 2) * 2 == Delta && "R_390_PC32DBL overflow");
819 writeInt32BE(LocalAddress, Delta / 2);
822 case ELF::R_390_PC32: {
823 int64_t Delta = (Value + Addend) - (Section.LoadAddress + Offset);
824 assert(int32_t(Delta) == Delta && "R_390_PC32 overflow");
825 writeInt32BE(LocalAddress, Delta);
829 writeInt64BE(LocalAddress, Value + Addend);
834 // The target location for the relocation is described by RE.SectionID and
835 // RE.Offset. RE.SectionID can be used to find the SectionEntry. Each
836 // SectionEntry has three members describing its location.
837 // SectionEntry::Address is the address at which the section has been loaded
838 // into memory in the current (host) process. SectionEntry::LoadAddress is the
839 // address that the section will have in the target process.
840 // SectionEntry::ObjAddress is the address of the bits for this section in the
841 // original emitted object image (also in the current address space).
843 // Relocations will be applied as if the section were loaded at
844 // SectionEntry::LoadAddress, but they will be applied at an address based
845 // on SectionEntry::Address. SectionEntry::ObjAddress will be used to refer to
846 // Target memory contents if they are required for value calculations.
848 // The Value parameter here is the load address of the symbol for the
849 // relocation to be applied. For relocations which refer to symbols in the
850 // current object Value will be the LoadAddress of the section in which
851 // the symbol resides (RE.Addend provides additional information about the
852 // symbol location). For external symbols, Value will be the address of the
853 // symbol in the target address space.
854 void RuntimeDyldELF::resolveRelocation(const RelocationEntry &RE,
856 const SectionEntry &Section = Sections[RE.SectionID];
857 return resolveRelocation(Section, RE.Offset, Value, RE.RelType, RE.Addend,
861 void RuntimeDyldELF::resolveRelocation(const SectionEntry &Section,
862 uint64_t Offset, uint64_t Value,
863 uint32_t Type, int64_t Addend,
864 uint64_t SymOffset) {
867 resolveX86_64Relocation(Section, Offset, Value, Type, Addend, SymOffset);
870 resolveX86Relocation(Section, Offset, (uint32_t)(Value & 0xffffffffL), Type,
871 (uint32_t)(Addend & 0xffffffffL));
873 case Triple::aarch64:
874 case Triple::aarch64_be:
875 resolveAArch64Relocation(Section, Offset, Value, Type, Addend);
877 case Triple::arm: // Fall through.
880 case Triple::thumbeb:
881 resolveARMRelocation(Section, Offset, (uint32_t)(Value & 0xffffffffL), Type,
882 (uint32_t)(Addend & 0xffffffffL));
884 case Triple::mips: // Fall through.
886 resolveMIPSRelocation(Section, Offset, (uint32_t)(Value & 0xffffffffL),
887 Type, (uint32_t)(Addend & 0xffffffffL));
889 case Triple::ppc64: // Fall through.
890 case Triple::ppc64le:
891 resolvePPC64Relocation(Section, Offset, Value, Type, Addend);
893 case Triple::systemz:
894 resolveSystemZRelocation(Section, Offset, Value, Type, Addend);
897 llvm_unreachable("Unsupported CPU type!");
901 relocation_iterator RuntimeDyldELF::processRelocationRef(
902 unsigned SectionID, relocation_iterator RelI,
903 const ObjectFile &Obj,
904 ObjSectionToIDMap &ObjSectionToID,
907 Check(RelI->getType(RelType));
909 Check(getELFRelocationAddend(*RelI, Addend));
910 symbol_iterator Symbol = RelI->getSymbol();
912 // Obtain the symbol name which is referenced in the relocation
913 StringRef TargetName;
914 if (Symbol != Obj.symbol_end())
915 Symbol->getName(TargetName);
916 DEBUG(dbgs() << "\t\tRelType: " << RelType << " Addend: " << Addend
917 << " TargetName: " << TargetName << "\n");
918 RelocationValueRef Value;
919 // First search for the symbol in the local symbol table
920 SymbolRef::Type SymType = SymbolRef::ST_Unknown;
922 // Search for the symbol in the global symbol table
923 SymbolTableMap::const_iterator gsi = GlobalSymbolTable.end();
924 if (Symbol != Obj.symbol_end()) {
925 gsi = GlobalSymbolTable.find(TargetName.data());
926 Symbol->getType(SymType);
928 if (gsi != GlobalSymbolTable.end()) {
929 Value.SectionID = gsi->second.first;
930 Value.Offset = gsi->second.second;
931 Value.Addend = gsi->second.second + Addend;
934 case SymbolRef::ST_Debug: {
935 // TODO: Now ELF SymbolRef::ST_Debug = STT_SECTION, it's not obviously
936 // and can be changed by another developers. Maybe best way is add
937 // a new symbol type ST_Section to SymbolRef and use it.
938 section_iterator si(Obj.section_end());
939 Symbol->getSection(si);
940 if (si == Obj.section_end())
941 llvm_unreachable("Symbol section not found, bad object file format!");
942 DEBUG(dbgs() << "\t\tThis is section symbol\n");
943 bool isCode = si->isText();
944 Value.SectionID = findOrEmitSection(Obj, (*si), isCode, ObjSectionToID);
945 Value.Addend = Addend;
948 case SymbolRef::ST_Data:
949 case SymbolRef::ST_Unknown: {
950 Value.SymbolName = TargetName.data();
951 Value.Addend = Addend;
953 // Absolute relocations will have a zero symbol ID (STN_UNDEF), which
954 // will manifest here as a NULL symbol name.
955 // We can set this as a valid (but empty) symbol name, and rely
956 // on addRelocationForSymbol to handle this.
957 if (!Value.SymbolName)
958 Value.SymbolName = "";
962 llvm_unreachable("Unresolved symbol type!");
968 Check(RelI->getOffset(Offset));
970 DEBUG(dbgs() << "\t\tSectionID: " << SectionID << " Offset: " << Offset
972 if ((Arch == Triple::aarch64 || Arch == Triple::aarch64_be) &&
973 (RelType == ELF::R_AARCH64_CALL26 || RelType == ELF::R_AARCH64_JUMP26)) {
974 // This is an AArch64 branch relocation, need to use a stub function.
975 DEBUG(dbgs() << "\t\tThis is an AArch64 branch relocation.");
976 SectionEntry &Section = Sections[SectionID];
978 // Look for an existing stub.
979 StubMap::const_iterator i = Stubs.find(Value);
980 if (i != Stubs.end()) {
981 resolveRelocation(Section, Offset, (uint64_t)Section.Address + i->second,
983 DEBUG(dbgs() << " Stub function found\n");
985 // Create a new stub function.
986 DEBUG(dbgs() << " Create a new stub function\n");
987 Stubs[Value] = Section.StubOffset;
988 uint8_t *StubTargetAddr =
989 createStubFunction(Section.Address + Section.StubOffset);
991 RelocationEntry REmovz_g3(SectionID, StubTargetAddr - Section.Address,
992 ELF::R_AARCH64_MOVW_UABS_G3, Value.Addend);
993 RelocationEntry REmovk_g2(SectionID, StubTargetAddr - Section.Address + 4,
994 ELF::R_AARCH64_MOVW_UABS_G2_NC, Value.Addend);
995 RelocationEntry REmovk_g1(SectionID, StubTargetAddr - Section.Address + 8,
996 ELF::R_AARCH64_MOVW_UABS_G1_NC, Value.Addend);
997 RelocationEntry REmovk_g0(SectionID,
998 StubTargetAddr - Section.Address + 12,
999 ELF::R_AARCH64_MOVW_UABS_G0_NC, Value.Addend);
1001 if (Value.SymbolName) {
1002 addRelocationForSymbol(REmovz_g3, Value.SymbolName);
1003 addRelocationForSymbol(REmovk_g2, Value.SymbolName);
1004 addRelocationForSymbol(REmovk_g1, Value.SymbolName);
1005 addRelocationForSymbol(REmovk_g0, Value.SymbolName);
1007 addRelocationForSection(REmovz_g3, Value.SectionID);
1008 addRelocationForSection(REmovk_g2, Value.SectionID);
1009 addRelocationForSection(REmovk_g1, Value.SectionID);
1010 addRelocationForSection(REmovk_g0, Value.SectionID);
1012 resolveRelocation(Section, Offset,
1013 (uint64_t)Section.Address + Section.StubOffset, RelType,
1015 Section.StubOffset += getMaxStubSize();
1017 } else if (Arch == Triple::arm &&
1018 (RelType == ELF::R_ARM_PC24 || RelType == ELF::R_ARM_CALL ||
1019 RelType == ELF::R_ARM_JUMP24)) {
1020 // This is an ARM branch relocation, need to use a stub function.
1021 DEBUG(dbgs() << "\t\tThis is an ARM branch relocation.");
1022 SectionEntry &Section = Sections[SectionID];
1024 // Look for an existing stub.
1025 StubMap::const_iterator i = Stubs.find(Value);
1026 if (i != Stubs.end()) {
1027 resolveRelocation(Section, Offset, (uint64_t)Section.Address + i->second,
1029 DEBUG(dbgs() << " Stub function found\n");
1031 // Create a new stub function.
1032 DEBUG(dbgs() << " Create a new stub function\n");
1033 Stubs[Value] = Section.StubOffset;
1034 uint8_t *StubTargetAddr =
1035 createStubFunction(Section.Address + Section.StubOffset);
1036 RelocationEntry RE(SectionID, StubTargetAddr - Section.Address,
1037 ELF::R_ARM_PRIVATE_0, Value.Addend);
1038 if (Value.SymbolName)
1039 addRelocationForSymbol(RE, Value.SymbolName);
1041 addRelocationForSection(RE, Value.SectionID);
1043 resolveRelocation(Section, Offset,
1044 (uint64_t)Section.Address + Section.StubOffset, RelType,
1046 Section.StubOffset += getMaxStubSize();
1048 } else if ((Arch == Triple::mipsel || Arch == Triple::mips) &&
1049 RelType == ELF::R_MIPS_26) {
1050 // This is an Mips branch relocation, need to use a stub function.
1051 DEBUG(dbgs() << "\t\tThis is a Mips branch relocation.");
1052 SectionEntry &Section = Sections[SectionID];
1053 uint8_t *Target = Section.Address + Offset;
1054 uint32_t *TargetAddress = (uint32_t *)Target;
1056 // Extract the addend from the instruction.
1057 uint32_t Addend = ((*TargetAddress) & 0x03ffffff) << 2;
1059 Value.Addend += Addend;
1061 // Look up for existing stub.
1062 StubMap::const_iterator i = Stubs.find(Value);
1063 if (i != Stubs.end()) {
1064 RelocationEntry RE(SectionID, Offset, RelType, i->second);
1065 addRelocationForSection(RE, SectionID);
1066 DEBUG(dbgs() << " Stub function found\n");
1068 // Create a new stub function.
1069 DEBUG(dbgs() << " Create a new stub function\n");
1070 Stubs[Value] = Section.StubOffset;
1071 uint8_t *StubTargetAddr =
1072 createStubFunction(Section.Address + Section.StubOffset);
1074 // Creating Hi and Lo relocations for the filled stub instructions.
1075 RelocationEntry REHi(SectionID, StubTargetAddr - Section.Address,
1076 ELF::R_MIPS_UNUSED1, Value.Addend);
1077 RelocationEntry RELo(SectionID, StubTargetAddr - Section.Address + 4,
1078 ELF::R_MIPS_UNUSED2, Value.Addend);
1080 if (Value.SymbolName) {
1081 addRelocationForSymbol(REHi, Value.SymbolName);
1082 addRelocationForSymbol(RELo, Value.SymbolName);
1084 addRelocationForSection(REHi, Value.SectionID);
1085 addRelocationForSection(RELo, Value.SectionID);
1088 RelocationEntry RE(SectionID, Offset, RelType, Section.StubOffset);
1089 addRelocationForSection(RE, SectionID);
1090 Section.StubOffset += getMaxStubSize();
1092 } else if (Arch == Triple::ppc64 || Arch == Triple::ppc64le) {
1093 if (RelType == ELF::R_PPC64_REL24) {
1094 // Determine ABI variant in use for this object.
1095 unsigned AbiVariant;
1096 Obj.getPlatformFlags(AbiVariant);
1097 AbiVariant &= ELF::EF_PPC64_ABI;
1098 // A PPC branch relocation will need a stub function if the target is
1099 // an external symbol (Symbol::ST_Unknown) or if the target address
1100 // is not within the signed 24-bits branch address.
1101 SectionEntry &Section = Sections[SectionID];
1102 uint8_t *Target = Section.Address + Offset;
1103 bool RangeOverflow = false;
1104 if (SymType != SymbolRef::ST_Unknown) {
1105 if (AbiVariant != 2) {
1106 // In the ELFv1 ABI, a function call may point to the .opd entry,
1107 // so the final symbol value is calculated based on the relocation
1108 // values in the .opd section.
1109 findOPDEntrySection(Obj, ObjSectionToID, Value);
1111 // In the ELFv2 ABI, a function symbol may provide a local entry
1112 // point, which must be used for direct calls.
1114 Symbol->getOther(SymOther);
1115 Value.Addend += ELF::decodePPC64LocalEntryOffset(SymOther);
1117 uint8_t *RelocTarget = Sections[Value.SectionID].Address + Value.Addend;
1118 int32_t delta = static_cast<int32_t>(Target - RelocTarget);
1119 // If it is within 24-bits branch range, just set the branch target
1120 if (SignExtend32<24>(delta) == delta) {
1121 RelocationEntry RE(SectionID, Offset, RelType, Value.Addend);
1122 if (Value.SymbolName)
1123 addRelocationForSymbol(RE, Value.SymbolName);
1125 addRelocationForSection(RE, Value.SectionID);
1127 RangeOverflow = true;
1130 if (SymType == SymbolRef::ST_Unknown || RangeOverflow == true) {
1131 // It is an external symbol (SymbolRef::ST_Unknown) or within a range
1132 // larger than 24-bits.
1133 StubMap::const_iterator i = Stubs.find(Value);
1134 if (i != Stubs.end()) {
1135 // Symbol function stub already created, just relocate to it
1136 resolveRelocation(Section, Offset,
1137 (uint64_t)Section.Address + i->second, RelType, 0);
1138 DEBUG(dbgs() << " Stub function found\n");
1140 // Create a new stub function.
1141 DEBUG(dbgs() << " Create a new stub function\n");
1142 Stubs[Value] = Section.StubOffset;
1143 uint8_t *StubTargetAddr =
1144 createStubFunction(Section.Address + Section.StubOffset,
1146 RelocationEntry RE(SectionID, StubTargetAddr - Section.Address,
1147 ELF::R_PPC64_ADDR64, Value.Addend);
1149 // Generates the 64-bits address loads as exemplified in section
1150 // 4.5.1 in PPC64 ELF ABI. Note that the relocations need to
1151 // apply to the low part of the instructions, so we have to update
1152 // the offset according to the target endianness.
1153 uint64_t StubRelocOffset = StubTargetAddr - Section.Address;
1154 if (!IsTargetLittleEndian)
1155 StubRelocOffset += 2;
1157 RelocationEntry REhst(SectionID, StubRelocOffset + 0,
1158 ELF::R_PPC64_ADDR16_HIGHEST, Value.Addend);
1159 RelocationEntry REhr(SectionID, StubRelocOffset + 4,
1160 ELF::R_PPC64_ADDR16_HIGHER, Value.Addend);
1161 RelocationEntry REh(SectionID, StubRelocOffset + 12,
1162 ELF::R_PPC64_ADDR16_HI, Value.Addend);
1163 RelocationEntry REl(SectionID, StubRelocOffset + 16,
1164 ELF::R_PPC64_ADDR16_LO, Value.Addend);
1166 if (Value.SymbolName) {
1167 addRelocationForSymbol(REhst, Value.SymbolName);
1168 addRelocationForSymbol(REhr, Value.SymbolName);
1169 addRelocationForSymbol(REh, Value.SymbolName);
1170 addRelocationForSymbol(REl, Value.SymbolName);
1172 addRelocationForSection(REhst, Value.SectionID);
1173 addRelocationForSection(REhr, Value.SectionID);
1174 addRelocationForSection(REh, Value.SectionID);
1175 addRelocationForSection(REl, Value.SectionID);
1178 resolveRelocation(Section, Offset,
1179 (uint64_t)Section.Address + Section.StubOffset,
1181 Section.StubOffset += getMaxStubSize();
1183 if (SymType == SymbolRef::ST_Unknown) {
1184 // Restore the TOC for external calls
1185 if (AbiVariant == 2)
1186 writeInt32BE(Target + 4, 0xE8410018); // ld r2,28(r1)
1188 writeInt32BE(Target + 4, 0xE8410028); // ld r2,40(r1)
1191 } else if (RelType == ELF::R_PPC64_TOC16 ||
1192 RelType == ELF::R_PPC64_TOC16_DS ||
1193 RelType == ELF::R_PPC64_TOC16_LO ||
1194 RelType == ELF::R_PPC64_TOC16_LO_DS ||
1195 RelType == ELF::R_PPC64_TOC16_HI ||
1196 RelType == ELF::R_PPC64_TOC16_HA) {
1197 // These relocations are supposed to subtract the TOC address from
1198 // the final value. This does not fit cleanly into the RuntimeDyld
1199 // scheme, since there may be *two* sections involved in determining
1200 // the relocation value (the section of the symbol refered to by the
1201 // relocation, and the TOC section associated with the current module).
1203 // Fortunately, these relocations are currently only ever generated
1204 // refering to symbols that themselves reside in the TOC, which means
1205 // that the two sections are actually the same. Thus they cancel out
1206 // and we can immediately resolve the relocation right now.
1208 case ELF::R_PPC64_TOC16: RelType = ELF::R_PPC64_ADDR16; break;
1209 case ELF::R_PPC64_TOC16_DS: RelType = ELF::R_PPC64_ADDR16_DS; break;
1210 case ELF::R_PPC64_TOC16_LO: RelType = ELF::R_PPC64_ADDR16_LO; break;
1211 case ELF::R_PPC64_TOC16_LO_DS: RelType = ELF::R_PPC64_ADDR16_LO_DS; break;
1212 case ELF::R_PPC64_TOC16_HI: RelType = ELF::R_PPC64_ADDR16_HI; break;
1213 case ELF::R_PPC64_TOC16_HA: RelType = ELF::R_PPC64_ADDR16_HA; break;
1214 default: llvm_unreachable("Wrong relocation type.");
1217 RelocationValueRef TOCValue;
1218 findPPC64TOCSection(Obj, ObjSectionToID, TOCValue);
1219 if (Value.SymbolName || Value.SectionID != TOCValue.SectionID)
1220 llvm_unreachable("Unsupported TOC relocation.");
1221 Value.Addend -= TOCValue.Addend;
1222 resolveRelocation(Sections[SectionID], Offset, Value.Addend, RelType, 0);
1224 // There are two ways to refer to the TOC address directly: either
1225 // via a ELF::R_PPC64_TOC relocation (where both symbol and addend are
1226 // ignored), or via any relocation that refers to the magic ".TOC."
1227 // symbols (in which case the addend is respected).
1228 if (RelType == ELF::R_PPC64_TOC) {
1229 RelType = ELF::R_PPC64_ADDR64;
1230 findPPC64TOCSection(Obj, ObjSectionToID, Value);
1231 } else if (TargetName == ".TOC.") {
1232 findPPC64TOCSection(Obj, ObjSectionToID, Value);
1233 Value.Addend += Addend;
1236 RelocationEntry RE(SectionID, Offset, RelType, Value.Addend);
1238 if (Value.SymbolName)
1239 addRelocationForSymbol(RE, Value.SymbolName);
1241 addRelocationForSection(RE, Value.SectionID);
1243 } else if (Arch == Triple::systemz &&
1244 (RelType == ELF::R_390_PLT32DBL || RelType == ELF::R_390_GOTENT)) {
1245 // Create function stubs for both PLT and GOT references, regardless of
1246 // whether the GOT reference is to data or code. The stub contains the
1247 // full address of the symbol, as needed by GOT references, and the
1248 // executable part only adds an overhead of 8 bytes.
1250 // We could try to conserve space by allocating the code and data
1251 // parts of the stub separately. However, as things stand, we allocate
1252 // a stub for every relocation, so using a GOT in JIT code should be
1253 // no less space efficient than using an explicit constant pool.
1254 DEBUG(dbgs() << "\t\tThis is a SystemZ indirect relocation.");
1255 SectionEntry &Section = Sections[SectionID];
1257 // Look for an existing stub.
1258 StubMap::const_iterator i = Stubs.find(Value);
1259 uintptr_t StubAddress;
1260 if (i != Stubs.end()) {
1261 StubAddress = uintptr_t(Section.Address) + i->second;
1262 DEBUG(dbgs() << " Stub function found\n");
1264 // Create a new stub function.
1265 DEBUG(dbgs() << " Create a new stub function\n");
1267 uintptr_t BaseAddress = uintptr_t(Section.Address);
1268 uintptr_t StubAlignment = getStubAlignment();
1269 StubAddress = (BaseAddress + Section.StubOffset + StubAlignment - 1) &
1271 unsigned StubOffset = StubAddress - BaseAddress;
1273 Stubs[Value] = StubOffset;
1274 createStubFunction((uint8_t *)StubAddress);
1275 RelocationEntry RE(SectionID, StubOffset + 8, ELF::R_390_64,
1277 if (Value.SymbolName)
1278 addRelocationForSymbol(RE, Value.SymbolName);
1280 addRelocationForSection(RE, Value.SectionID);
1281 Section.StubOffset = StubOffset + getMaxStubSize();
1284 if (RelType == ELF::R_390_GOTENT)
1285 resolveRelocation(Section, Offset, StubAddress + 8, ELF::R_390_PC32DBL,
1288 resolveRelocation(Section, Offset, StubAddress, RelType, Addend);
1289 } else if (Arch == Triple::x86_64 && RelType == ELF::R_X86_64_PLT32) {
1290 // The way the PLT relocations normally work is that the linker allocates
1292 // PLT and this relocation makes a PC-relative call into the PLT. The PLT
1293 // entry will then jump to an address provided by the GOT. On first call,
1295 // GOT address will point back into PLT code that resolves the symbol. After
1296 // the first call, the GOT entry points to the actual function.
1298 // For local functions we're ignoring all of that here and just replacing
1299 // the PLT32 relocation type with PC32, which will translate the relocation
1300 // into a PC-relative call directly to the function. For external symbols we
1301 // can't be sure the function will be within 2^32 bytes of the call site, so
1302 // we need to create a stub, which calls into the GOT. This case is
1303 // equivalent to the usual PLT implementation except that we use the stub
1304 // mechanism in RuntimeDyld (which puts stubs at the end of the section)
1305 // rather than allocating a PLT section.
1306 if (Value.SymbolName) {
1307 // This is a call to an external function.
1308 // Look for an existing stub.
1309 SectionEntry &Section = Sections[SectionID];
1310 StubMap::const_iterator i = Stubs.find(Value);
1311 uintptr_t StubAddress;
1312 if (i != Stubs.end()) {
1313 StubAddress = uintptr_t(Section.Address) + i->second;
1314 DEBUG(dbgs() << " Stub function found\n");
1316 // Create a new stub function (equivalent to a PLT entry).
1317 DEBUG(dbgs() << " Create a new stub function\n");
1319 uintptr_t BaseAddress = uintptr_t(Section.Address);
1320 uintptr_t StubAlignment = getStubAlignment();
1321 StubAddress = (BaseAddress + Section.StubOffset + StubAlignment - 1) &
1323 unsigned StubOffset = StubAddress - BaseAddress;
1324 Stubs[Value] = StubOffset;
1325 createStubFunction((uint8_t *)StubAddress);
1327 // Create a GOT entry for the external function.
1328 GOTEntries.push_back(Value);
1330 // Make our stub function a relative call to the GOT entry.
1331 RelocationEntry RE(SectionID, StubOffset + 2, ELF::R_X86_64_GOTPCREL,
1333 addRelocationForSymbol(RE, Value.SymbolName);
1335 // Bump our stub offset counter
1336 Section.StubOffset = StubOffset + getMaxStubSize();
1339 // Make the target call a call into the stub table.
1340 resolveRelocation(Section, Offset, StubAddress, ELF::R_X86_64_PC32,
1343 RelocationEntry RE(SectionID, Offset, ELF::R_X86_64_PC32, Value.Addend,
1345 addRelocationForSection(RE, Value.SectionID);
1348 if (Arch == Triple::x86_64 && RelType == ELF::R_X86_64_GOTPCREL) {
1349 GOTEntries.push_back(Value);
1351 RelocationEntry RE(SectionID, Offset, RelType, Value.Addend, Value.Offset);
1352 if (Value.SymbolName)
1353 addRelocationForSymbol(RE, Value.SymbolName);
1355 addRelocationForSection(RE, Value.SectionID);
1360 void RuntimeDyldELF::updateGOTEntries(StringRef Name, uint64_t Addr) {
1362 SmallVectorImpl<std::pair<SID, GOTRelocations>>::iterator it;
1363 SmallVectorImpl<std::pair<SID, GOTRelocations>>::iterator end = GOTs.end();
1365 for (it = GOTs.begin(); it != end; ++it) {
1366 GOTRelocations &GOTEntries = it->second;
1367 for (int i = 0, e = GOTEntries.size(); i != e; ++i) {
1368 if (GOTEntries[i].SymbolName != nullptr &&
1369 GOTEntries[i].SymbolName == Name) {
1370 GOTEntries[i].Offset = Addr;
1376 size_t RuntimeDyldELF::getGOTEntrySize() {
1377 // We don't use the GOT in all of these cases, but it's essentially free
1378 // to put them all here.
1381 case Triple::x86_64:
1382 case Triple::aarch64:
1383 case Triple::aarch64_be:
1385 case Triple::ppc64le:
1386 case Triple::systemz:
1387 Result = sizeof(uint64_t);
1393 case Triple::mipsel:
1394 Result = sizeof(uint32_t);
1397 llvm_unreachable("Unsupported CPU type!");
1402 uint64_t RuntimeDyldELF::findGOTEntry(uint64_t LoadAddress, uint64_t Offset) {
1404 const size_t GOTEntrySize = getGOTEntrySize();
1406 SmallVectorImpl<std::pair<SID, GOTRelocations>>::const_iterator it;
1407 SmallVectorImpl<std::pair<SID, GOTRelocations>>::const_iterator end =
1411 for (it = GOTs.begin(); it != end; ++it) {
1412 SID GOTSectionID = it->first;
1413 const GOTRelocations &GOTEntries = it->second;
1415 // Find the matching entry in our vector.
1416 uint64_t SymbolOffset = 0;
1417 for (int i = 0, e = GOTEntries.size(); i != e; ++i) {
1418 if (!GOTEntries[i].SymbolName) {
1419 if (getSectionLoadAddress(GOTEntries[i].SectionID) == LoadAddress &&
1420 GOTEntries[i].Offset == Offset) {
1422 SymbolOffset = GOTEntries[i].Offset;
1426 // GOT entries for external symbols use the addend as the address when
1427 // the external symbol has been resolved.
1428 if (GOTEntries[i].Offset == LoadAddress) {
1430 // Don't use the Addend here. The relocation handler will use it.
1436 if (GOTIndex != -1) {
1437 if (GOTEntrySize == sizeof(uint64_t)) {
1438 uint64_t *LocalGOTAddr = (uint64_t *)getSectionAddress(GOTSectionID);
1439 // Fill in this entry with the address of the symbol being referenced.
1440 LocalGOTAddr[GOTIndex] = LoadAddress + SymbolOffset;
1442 uint32_t *LocalGOTAddr = (uint32_t *)getSectionAddress(GOTSectionID);
1443 // Fill in this entry with the address of the symbol being referenced.
1444 LocalGOTAddr[GOTIndex] = (uint32_t)(LoadAddress + SymbolOffset);
1447 // Calculate the load address of this entry
1448 return getSectionLoadAddress(GOTSectionID) + (GOTIndex * GOTEntrySize);
1452 assert(GOTIndex != -1 && "Unable to find requested GOT entry.");
1456 void RuntimeDyldELF::finalizeLoad(const ObjectFile &Obj,
1457 ObjSectionToIDMap &SectionMap) {
1458 // If necessary, allocate the global offset table
1460 // Allocate the GOT if necessary
1461 size_t numGOTEntries = GOTEntries.size();
1462 if (numGOTEntries != 0) {
1463 // Allocate memory for the section
1464 unsigned SectionID = Sections.size();
1465 size_t TotalSize = numGOTEntries * getGOTEntrySize();
1466 uint8_t *Addr = MemMgr->allocateDataSection(TotalSize, getGOTEntrySize(),
1467 SectionID, ".got", false);
1469 report_fatal_error("Unable to allocate memory for GOT!");
1471 GOTs.push_back(std::make_pair(SectionID, GOTEntries));
1472 Sections.push_back(SectionEntry(".got", Addr, TotalSize, 0));
1473 // For now, initialize all GOT entries to zero. We'll fill them in as
1474 // needed when GOT-based relocations are applied.
1475 memset(Addr, 0, TotalSize);
1478 report_fatal_error("Unable to allocate memory for GOT!");
1481 // Look for and record the EH frame section.
1482 ObjSectionToIDMap::iterator i, e;
1483 for (i = SectionMap.begin(), e = SectionMap.end(); i != e; ++i) {
1484 const SectionRef &Section = i->first;
1486 Section.getName(Name);
1487 if (Name == ".eh_frame") {
1488 UnregisteredEHFrameSections.push_back(i->second);
1494 bool RuntimeDyldELF::isCompatibleFile(const object::ObjectFile &Obj) const {