1 //===---- MachO_arm64.cpp - JIT linker implementation for MachO/arm64 -----===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // MachO/arm64 jit-link implementation. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #include "llvm/ExecutionEngine/JITLink/MachO_arm64.h" 14 15 #include "BasicGOTAndStubsBuilder.h" 16 #include "MachOLinkGraphBuilder.h" 17 18 #define DEBUG_TYPE "jitlink" 19 20 using namespace llvm; 21 using namespace llvm::jitlink; 22 using namespace llvm::jitlink::MachO_arm64_Edges; 23 24 namespace { 25 26 class MachOLinkGraphBuilder_arm64 : public MachOLinkGraphBuilder { 27 public: 28 MachOLinkGraphBuilder_arm64(const object::MachOObjectFile &Obj) 29 : MachOLinkGraphBuilder(Obj, Triple("arm64-apple-darwin")), 30 NumSymbols(Obj.getSymtabLoadCommand().nsyms) {} 31 32 private: 33 static Expected<MachOARM64RelocationKind> 34 getRelocationKind(const MachO::relocation_info &RI) { 35 switch (RI.r_type) { 36 case MachO::ARM64_RELOC_UNSIGNED: 37 if (!RI.r_pcrel) { 38 if (RI.r_length == 3) 39 return RI.r_extern ? Pointer64 : Pointer64Anon; 40 else if (RI.r_length == 2) 41 return Pointer32; 42 } 43 break; 44 case MachO::ARM64_RELOC_SUBTRACTOR: 45 // SUBTRACTOR must be non-pc-rel, extern, with length 2 or 3. 46 // Initially represent SUBTRACTOR relocations with 'Delta<W>'. 47 // They may be turned into NegDelta<W> by parsePairRelocation. 48 if (!RI.r_pcrel && RI.r_extern) { 49 if (RI.r_length == 2) 50 return Delta32; 51 else if (RI.r_length == 3) 52 return Delta64; 53 } 54 break; 55 case MachO::ARM64_RELOC_BRANCH26: 56 if (RI.r_pcrel && RI.r_extern && RI.r_length == 2) 57 return Branch26; 58 break; 59 case MachO::ARM64_RELOC_PAGE21: 60 if (RI.r_pcrel && RI.r_extern && RI.r_length == 2) 61 return Page21; 62 break; 63 case MachO::ARM64_RELOC_PAGEOFF12: 64 if (!RI.r_pcrel && RI.r_extern && RI.r_length == 2) 65 return PageOffset12; 66 break; 67 case MachO::ARM64_RELOC_GOT_LOAD_PAGE21: 68 if (RI.r_pcrel && RI.r_extern && RI.r_length == 2) 69 return GOTPage21; 70 break; 71 case MachO::ARM64_RELOC_GOT_LOAD_PAGEOFF12: 72 if (!RI.r_pcrel && RI.r_extern && RI.r_length == 2) 73 return GOTPageOffset12; 74 break; 75 case MachO::ARM64_RELOC_POINTER_TO_GOT: 76 if (RI.r_pcrel && RI.r_extern && RI.r_length == 2) 77 return PointerToGOT; 78 break; 79 case MachO::ARM64_RELOC_ADDEND: 80 if (!RI.r_pcrel && !RI.r_extern && RI.r_length == 2) 81 return PairedAddend; 82 break; 83 } 84 85 return make_error<JITLinkError>( 86 "Unsupported arm64 relocation: address=" + 87 formatv("{0:x8}", RI.r_address) + 88 ", symbolnum=" + formatv("{0:x6}", RI.r_symbolnum) + 89 ", kind=" + formatv("{0:x1}", RI.r_type) + 90 ", pc_rel=" + (RI.r_pcrel ? "true" : "false") + 91 ", extern=" + (RI.r_extern ? "true" : "false") + 92 ", length=" + formatv("{0:d}", RI.r_length)); 93 } 94 95 using PairRelocInfo = 96 std::tuple<MachOARM64RelocationKind, Symbol *, uint64_t>; 97 98 // Parses paired SUBTRACTOR/UNSIGNED relocations and, on success, 99 // returns the edge kind and addend to be used. 100 Expected<PairRelocInfo> 101 parsePairRelocation(Block &BlockToFix, Edge::Kind SubtractorKind, 102 const MachO::relocation_info &SubRI, 103 JITTargetAddress FixupAddress, const char *FixupContent, 104 object::relocation_iterator &UnsignedRelItr, 105 object::relocation_iterator &RelEnd) { 106 using namespace support; 107 108 assert(((SubtractorKind == Delta32 && SubRI.r_length == 2) || 109 (SubtractorKind == Delta64 && SubRI.r_length == 3)) && 110 "Subtractor kind should match length"); 111 assert(SubRI.r_extern && "SUBTRACTOR reloc symbol should be extern"); 112 assert(!SubRI.r_pcrel && "SUBTRACTOR reloc should not be PCRel"); 113 114 if (UnsignedRelItr == RelEnd) 115 return make_error<JITLinkError>("arm64 SUBTRACTOR without paired " 116 "UNSIGNED relocation"); 117 118 auto UnsignedRI = getRelocationInfo(UnsignedRelItr); 119 120 if (SubRI.r_address != UnsignedRI.r_address) 121 return make_error<JITLinkError>("arm64 SUBTRACTOR and paired UNSIGNED " 122 "point to different addresses"); 123 124 if (SubRI.r_length != UnsignedRI.r_length) 125 return make_error<JITLinkError>("length of arm64 SUBTRACTOR and paired " 126 "UNSIGNED reloc must match"); 127 128 Symbol *FromSymbol; 129 if (auto FromSymbolOrErr = findSymbolByIndex(SubRI.r_symbolnum)) 130 FromSymbol = FromSymbolOrErr->GraphSymbol; 131 else 132 return FromSymbolOrErr.takeError(); 133 134 // Read the current fixup value. 135 uint64_t FixupValue = 0; 136 if (SubRI.r_length == 3) 137 FixupValue = *(const little64_t *)FixupContent; 138 else 139 FixupValue = *(const little32_t *)FixupContent; 140 141 // Find 'ToSymbol' using symbol number or address, depending on whether the 142 // paired UNSIGNED relocation is extern. 143 Symbol *ToSymbol = nullptr; 144 if (UnsignedRI.r_extern) { 145 // Find target symbol by symbol index. 146 if (auto ToSymbolOrErr = findSymbolByIndex(UnsignedRI.r_symbolnum)) 147 ToSymbol = ToSymbolOrErr->GraphSymbol; 148 else 149 return ToSymbolOrErr.takeError(); 150 } else { 151 auto ToSymbolSec = findSectionByIndex(UnsignedRI.r_symbolnum - 1); 152 if (!ToSymbolSec) 153 return ToSymbolSec.takeError(); 154 ToSymbol = getSymbolByAddress(ToSymbolSec->Address); 155 assert(ToSymbol && "No symbol for section"); 156 FixupValue -= ToSymbol->getAddress(); 157 } 158 159 MachOARM64RelocationKind DeltaKind; 160 Symbol *TargetSymbol; 161 uint64_t Addend; 162 if (&BlockToFix == &FromSymbol->getAddressable()) { 163 TargetSymbol = ToSymbol; 164 DeltaKind = (SubRI.r_length == 3) ? Delta64 : Delta32; 165 Addend = FixupValue + (FixupAddress - FromSymbol->getAddress()); 166 // FIXME: handle extern 'from'. 167 } else if (&BlockToFix == &ToSymbol->getAddressable()) { 168 TargetSymbol = &*FromSymbol; 169 DeltaKind = (SubRI.r_length == 3) ? NegDelta64 : NegDelta32; 170 Addend = FixupValue - (FixupAddress - ToSymbol->getAddress()); 171 } else { 172 // BlockToFix was neither FromSymbol nor ToSymbol. 173 return make_error<JITLinkError>("SUBTRACTOR relocation must fix up " 174 "either 'A' or 'B' (or a symbol in one " 175 "of their alt-entry groups)"); 176 } 177 178 return PairRelocInfo(DeltaKind, TargetSymbol, Addend); 179 } 180 181 Error addRelocations() override { 182 using namespace support; 183 auto &Obj = getObject(); 184 185 LLVM_DEBUG(dbgs() << "Processing relocations:\n"); 186 187 for (auto &S : Obj.sections()) { 188 189 JITTargetAddress SectionAddress = S.getAddress(); 190 191 // Skip relocations virtual sections. 192 if (S.isVirtual()) { 193 if (S.relocation_begin() != S.relocation_end()) 194 return make_error<JITLinkError>("Virtual section contains " 195 "relocations"); 196 continue; 197 } 198 199 // Skip relocations for debug symbols. 200 { 201 auto &NSec = 202 getSectionByIndex(Obj.getSectionIndex(S.getRawDataRefImpl())); 203 if (!NSec.GraphSection) { 204 LLVM_DEBUG({ 205 dbgs() << " Skipping relocations for MachO section " 206 << NSec.SegName << "/" << NSec.SectName 207 << " which has no associated graph section\n"; 208 }); 209 continue; 210 } 211 } 212 213 for (auto RelItr = S.relocation_begin(), RelEnd = S.relocation_end(); 214 RelItr != RelEnd; ++RelItr) { 215 216 MachO::relocation_info RI = getRelocationInfo(RelItr); 217 218 // Sanity check the relocation kind. 219 auto Kind = getRelocationKind(RI); 220 if (!Kind) 221 return Kind.takeError(); 222 223 // Find the address of the value to fix up. 224 JITTargetAddress FixupAddress = SectionAddress + (uint32_t)RI.r_address; 225 226 LLVM_DEBUG({ 227 auto &NSec = 228 getSectionByIndex(Obj.getSectionIndex(S.getRawDataRefImpl())); 229 dbgs() << " " << NSec.SectName << " + " 230 << formatv("{0:x8}", RI.r_address) << ":\n"; 231 }); 232 233 // Find the block that the fixup points to. 234 Block *BlockToFix = nullptr; 235 { 236 auto SymbolToFixOrErr = findSymbolByAddress(FixupAddress); 237 if (!SymbolToFixOrErr) 238 return SymbolToFixOrErr.takeError(); 239 BlockToFix = &SymbolToFixOrErr->getBlock(); 240 } 241 242 if (FixupAddress + static_cast<JITTargetAddress>(1ULL << RI.r_length) > 243 BlockToFix->getAddress() + BlockToFix->getContent().size()) 244 return make_error<JITLinkError>( 245 "Relocation content extends past end of fixup block"); 246 247 // Get a pointer to the fixup content. 248 const char *FixupContent = BlockToFix->getContent().data() + 249 (FixupAddress - BlockToFix->getAddress()); 250 251 // The target symbol and addend will be populated by the switch below. 252 Symbol *TargetSymbol = nullptr; 253 uint64_t Addend = 0; 254 255 if (*Kind == PairedAddend) { 256 // If this is an Addend relocation then process it and move to the 257 // paired reloc. 258 259 Addend = SignExtend64(RI.r_symbolnum, 24); 260 261 if (RelItr == RelEnd) 262 return make_error<JITLinkError>("Unpaired Addend reloc at " + 263 formatv("{0:x16}", FixupAddress)); 264 ++RelItr; 265 RI = getRelocationInfo(RelItr); 266 267 Kind = getRelocationKind(RI); 268 if (!Kind) 269 return Kind.takeError(); 270 271 if (*Kind != Branch26 && *Kind != Page21 && *Kind != PageOffset12) 272 return make_error<JITLinkError>( 273 "Invalid relocation pair: Addend + " + 274 getMachOARM64RelocationKindName(*Kind)); 275 276 LLVM_DEBUG({ 277 dbgs() << " Addend: value = " << formatv("{0:x6}", Addend) 278 << ", pair is " << getMachOARM64RelocationKindName(*Kind) 279 << "\n"; 280 }); 281 282 // Find the address of the value to fix up. 283 JITTargetAddress PairedFixupAddress = 284 SectionAddress + (uint32_t)RI.r_address; 285 if (PairedFixupAddress != FixupAddress) 286 return make_error<JITLinkError>("Paired relocation points at " 287 "different target"); 288 } 289 290 switch (*Kind) { 291 case Branch26: { 292 if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum)) 293 TargetSymbol = TargetSymbolOrErr->GraphSymbol; 294 else 295 return TargetSymbolOrErr.takeError(); 296 uint32_t Instr = *(const ulittle32_t *)FixupContent; 297 if ((Instr & 0x7fffffff) != 0x14000000) 298 return make_error<JITLinkError>("BRANCH26 target is not a B or BL " 299 "instruction with a zero addend"); 300 break; 301 } 302 case Pointer32: 303 if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum)) 304 TargetSymbol = TargetSymbolOrErr->GraphSymbol; 305 else 306 return TargetSymbolOrErr.takeError(); 307 Addend = *(const ulittle32_t *)FixupContent; 308 break; 309 case Pointer64: 310 if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum)) 311 TargetSymbol = TargetSymbolOrErr->GraphSymbol; 312 else 313 return TargetSymbolOrErr.takeError(); 314 Addend = *(const ulittle64_t *)FixupContent; 315 break; 316 case Pointer64Anon: { 317 JITTargetAddress TargetAddress = *(const ulittle64_t *)FixupContent; 318 if (auto TargetSymbolOrErr = findSymbolByAddress(TargetAddress)) 319 TargetSymbol = &*TargetSymbolOrErr; 320 else 321 return TargetSymbolOrErr.takeError(); 322 Addend = TargetAddress - TargetSymbol->getAddress(); 323 break; 324 } 325 case Page21: 326 case GOTPage21: { 327 if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum)) 328 TargetSymbol = TargetSymbolOrErr->GraphSymbol; 329 else 330 return TargetSymbolOrErr.takeError(); 331 uint32_t Instr = *(const ulittle32_t *)FixupContent; 332 if ((Instr & 0xffffffe0) != 0x90000000) 333 return make_error<JITLinkError>("PAGE21/GOTPAGE21 target is not an " 334 "ADRP instruction with a zero " 335 "addend"); 336 break; 337 } 338 case PageOffset12: { 339 if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum)) 340 TargetSymbol = TargetSymbolOrErr->GraphSymbol; 341 else 342 return TargetSymbolOrErr.takeError(); 343 uint32_t Instr = *(const ulittle32_t *)FixupContent; 344 uint32_t EncodedAddend = (Instr & 0x003FFC00) >> 10; 345 if (EncodedAddend != 0) 346 return make_error<JITLinkError>("GOTPAGEOFF12 target has non-zero " 347 "encoded addend"); 348 break; 349 } 350 case GOTPageOffset12: { 351 if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum)) 352 TargetSymbol = TargetSymbolOrErr->GraphSymbol; 353 else 354 return TargetSymbolOrErr.takeError(); 355 uint32_t Instr = *(const ulittle32_t *)FixupContent; 356 if ((Instr & 0xfffffc00) != 0xf9400000) 357 return make_error<JITLinkError>("GOTPAGEOFF12 target is not an LDR " 358 "immediate instruction with a zero " 359 "addend"); 360 break; 361 } 362 case PointerToGOT: 363 if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum)) 364 TargetSymbol = TargetSymbolOrErr->GraphSymbol; 365 else 366 return TargetSymbolOrErr.takeError(); 367 break; 368 case Delta32: 369 case Delta64: { 370 // We use Delta32/Delta64 to represent SUBTRACTOR relocations. 371 // parsePairRelocation handles the paired reloc, and returns the 372 // edge kind to be used (either Delta32/Delta64, or 373 // NegDelta32/NegDelta64, depending on the direction of the 374 // subtraction) along with the addend. 375 auto PairInfo = 376 parsePairRelocation(*BlockToFix, *Kind, RI, FixupAddress, 377 FixupContent, ++RelItr, RelEnd); 378 if (!PairInfo) 379 return PairInfo.takeError(); 380 std::tie(*Kind, TargetSymbol, Addend) = *PairInfo; 381 assert(TargetSymbol && "No target symbol from parsePairRelocation?"); 382 break; 383 } 384 default: 385 llvm_unreachable("Special relocation kind should not appear in " 386 "mach-o file"); 387 } 388 389 LLVM_DEBUG({ 390 dbgs() << " "; 391 Edge GE(*Kind, FixupAddress - BlockToFix->getAddress(), *TargetSymbol, 392 Addend); 393 printEdge(dbgs(), *BlockToFix, GE, 394 getMachOARM64RelocationKindName(*Kind)); 395 dbgs() << "\n"; 396 }); 397 BlockToFix->addEdge(*Kind, FixupAddress - BlockToFix->getAddress(), 398 *TargetSymbol, Addend); 399 } 400 } 401 return Error::success(); 402 } 403 404 unsigned NumSymbols = 0; 405 }; 406 407 class MachO_arm64_GOTAndStubsBuilder 408 : public BasicGOTAndStubsBuilder<MachO_arm64_GOTAndStubsBuilder> { 409 public: 410 MachO_arm64_GOTAndStubsBuilder(LinkGraph &G) 411 : BasicGOTAndStubsBuilder<MachO_arm64_GOTAndStubsBuilder>(G) {} 412 413 bool isGOTEdge(Edge &E) const { 414 return E.getKind() == GOTPage21 || E.getKind() == GOTPageOffset12 || 415 E.getKind() == PointerToGOT; 416 } 417 418 Symbol &createGOTEntry(Symbol &Target) { 419 auto &GOTEntryBlock = G.createContentBlock( 420 getGOTSection(), getGOTEntryBlockContent(), 0, 8, 0); 421 GOTEntryBlock.addEdge(Pointer64, 0, Target, 0); 422 return G.addAnonymousSymbol(GOTEntryBlock, 0, 8, false, false); 423 } 424 425 void fixGOTEdge(Edge &E, Symbol &GOTEntry) { 426 if (E.getKind() == GOTPage21 || E.getKind() == GOTPageOffset12) { 427 // Update the target, but leave the edge addend as-is. 428 E.setTarget(GOTEntry); 429 } else if (E.getKind() == PointerToGOT) { 430 E.setTarget(GOTEntry); 431 E.setKind(Delta32); 432 } else 433 llvm_unreachable("Not a GOT edge?"); 434 } 435 436 bool isExternalBranchEdge(Edge &E) { 437 return E.getKind() == Branch26 && !E.getTarget().isDefined(); 438 } 439 440 Symbol &createStub(Symbol &Target) { 441 auto &StubContentBlock = 442 G.createContentBlock(getStubsSection(), getStubBlockContent(), 0, 1, 0); 443 // Re-use GOT entries for stub targets. 444 auto &GOTEntrySymbol = getGOTEntrySymbol(Target); 445 StubContentBlock.addEdge(LDRLiteral19, 0, GOTEntrySymbol, 0); 446 return G.addAnonymousSymbol(StubContentBlock, 0, 8, true, false); 447 } 448 449 void fixExternalBranchEdge(Edge &E, Symbol &Stub) { 450 assert(E.getKind() == Branch26 && "Not a Branch32 edge?"); 451 assert(E.getAddend() == 0 && "Branch32 edge has non-zero addend?"); 452 E.setTarget(Stub); 453 } 454 455 private: 456 Section &getGOTSection() { 457 if (!GOTSection) 458 GOTSection = &G.createSection("$__GOT", sys::Memory::MF_READ); 459 return *GOTSection; 460 } 461 462 Section &getStubsSection() { 463 if (!StubsSection) { 464 auto StubsProt = static_cast<sys::Memory::ProtectionFlags>( 465 sys::Memory::MF_READ | sys::Memory::MF_EXEC); 466 StubsSection = &G.createSection("$__STUBS", StubsProt); 467 } 468 return *StubsSection; 469 } 470 471 StringRef getGOTEntryBlockContent() { 472 return StringRef(reinterpret_cast<const char *>(NullGOTEntryContent), 473 sizeof(NullGOTEntryContent)); 474 } 475 476 StringRef getStubBlockContent() { 477 return StringRef(reinterpret_cast<const char *>(StubContent), 478 sizeof(StubContent)); 479 } 480 481 static const uint8_t NullGOTEntryContent[8]; 482 static const uint8_t StubContent[8]; 483 Section *GOTSection = nullptr; 484 Section *StubsSection = nullptr; 485 }; 486 487 const uint8_t MachO_arm64_GOTAndStubsBuilder::NullGOTEntryContent[8] = { 488 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}; 489 const uint8_t MachO_arm64_GOTAndStubsBuilder::StubContent[8] = { 490 0x10, 0x00, 0x00, 0x58, // LDR x16, <literal> 491 0x00, 0x02, 0x1f, 0xd6 // BR x16 492 }; 493 494 } // namespace 495 496 namespace llvm { 497 namespace jitlink { 498 499 class MachOJITLinker_arm64 : public JITLinker<MachOJITLinker_arm64> { 500 friend class JITLinker<MachOJITLinker_arm64>; 501 502 public: 503 MachOJITLinker_arm64(std::unique_ptr<JITLinkContext> Ctx, 504 std::unique_ptr<LinkGraph> G, 505 PassConfiguration PassConfig) 506 : JITLinker(std::move(Ctx), std::move(G), std::move(PassConfig)) {} 507 508 private: 509 StringRef getEdgeKindName(Edge::Kind R) const override { 510 return getMachOARM64RelocationKindName(R); 511 } 512 513 static Error targetOutOfRangeError(const Block &B, const Edge &E) { 514 std::string ErrMsg; 515 { 516 raw_string_ostream ErrStream(ErrMsg); 517 ErrStream << "Relocation target out of range: "; 518 printEdge(ErrStream, B, E, getMachOARM64RelocationKindName(E.getKind())); 519 ErrStream << "\n"; 520 } 521 return make_error<JITLinkError>(std::move(ErrMsg)); 522 } 523 524 static unsigned getPageOffset12Shift(uint32_t Instr) { 525 constexpr uint32_t LoadStoreImm12Mask = 0x3b000000; 526 constexpr uint32_t Vec128Mask = 0x04800000; 527 528 if ((Instr & LoadStoreImm12Mask) == 0x39000000) { 529 uint32_t ImplicitShift = Instr >> 30; 530 if (ImplicitShift == 0) 531 if ((Instr & Vec128Mask) == Vec128Mask) 532 ImplicitShift = 4; 533 534 return ImplicitShift; 535 } 536 537 return 0; 538 } 539 540 Error applyFixup(Block &B, const Edge &E, char *BlockWorkingMem) const { 541 using namespace support; 542 543 char *FixupPtr = BlockWorkingMem + E.getOffset(); 544 JITTargetAddress FixupAddress = B.getAddress() + E.getOffset(); 545 546 switch (E.getKind()) { 547 case Branch26: { 548 assert((FixupAddress & 0x3) == 0 && "Branch-inst is not 32-bit aligned"); 549 550 int64_t Value = E.getTarget().getAddress() - FixupAddress + E.getAddend(); 551 552 if (static_cast<uint64_t>(Value) & 0x3) 553 return make_error<JITLinkError>("Branch26 target is not 32-bit " 554 "aligned"); 555 556 if (Value < -(1 << 27) || Value > ((1 << 27) - 1)) 557 return targetOutOfRangeError(B, E); 558 559 uint32_t RawInstr = *(little32_t *)FixupPtr; 560 assert((RawInstr & 0x7fffffff) == 0x14000000 && 561 "RawInstr isn't a B or BR immediate instruction"); 562 uint32_t Imm = (static_cast<uint32_t>(Value) & ((1 << 28) - 1)) >> 2; 563 uint32_t FixedInstr = RawInstr | Imm; 564 *(little32_t *)FixupPtr = FixedInstr; 565 break; 566 } 567 case Pointer32: { 568 uint64_t Value = E.getTarget().getAddress() + E.getAddend(); 569 if (Value > std::numeric_limits<uint32_t>::max()) 570 return targetOutOfRangeError(B, E); 571 *(ulittle32_t *)FixupPtr = Value; 572 break; 573 } 574 case Pointer64: 575 case Pointer64Anon: { 576 uint64_t Value = E.getTarget().getAddress() + E.getAddend(); 577 *(ulittle64_t *)FixupPtr = Value; 578 break; 579 } 580 case Page21: 581 case GOTPage21: { 582 assert((E.getKind() != GOTPage21 || E.getAddend() == 0) && 583 "GOTPAGE21 with non-zero addend"); 584 uint64_t TargetPage = 585 (E.getTarget().getAddress() + E.getAddend()) & 586 ~static_cast<uint64_t>(4096 - 1); 587 uint64_t PCPage = FixupAddress & ~static_cast<uint64_t>(4096 - 1); 588 589 int64_t PageDelta = TargetPage - PCPage; 590 if (PageDelta < -(1 << 30) || PageDelta > ((1 << 30) - 1)) 591 return targetOutOfRangeError(B, E); 592 593 uint32_t RawInstr = *(ulittle32_t *)FixupPtr; 594 assert((RawInstr & 0xffffffe0) == 0x90000000 && 595 "RawInstr isn't an ADRP instruction"); 596 uint32_t ImmLo = (static_cast<uint64_t>(PageDelta) >> 12) & 0x3; 597 uint32_t ImmHi = (static_cast<uint64_t>(PageDelta) >> 14) & 0x7ffff; 598 uint32_t FixedInstr = RawInstr | (ImmLo << 29) | (ImmHi << 5); 599 *(ulittle32_t *)FixupPtr = FixedInstr; 600 break; 601 } 602 case PageOffset12: { 603 uint64_t TargetOffset = 604 (E.getTarget().getAddress() + E.getAddend()) & 0xfff; 605 606 uint32_t RawInstr = *(ulittle32_t *)FixupPtr; 607 unsigned ImmShift = getPageOffset12Shift(RawInstr); 608 609 if (TargetOffset & ((1 << ImmShift) - 1)) 610 return make_error<JITLinkError>("PAGEOFF12 target is not aligned"); 611 612 uint32_t EncodedImm = (TargetOffset >> ImmShift) << 10; 613 uint32_t FixedInstr = RawInstr | EncodedImm; 614 *(ulittle32_t *)FixupPtr = FixedInstr; 615 break; 616 } 617 case GOTPageOffset12: { 618 assert(E.getAddend() == 0 && "GOTPAGEOF12 with non-zero addend"); 619 620 uint32_t RawInstr = *(ulittle32_t *)FixupPtr; 621 assert((RawInstr & 0xfffffc00) == 0xf9400000 && 622 "RawInstr isn't a 64-bit LDR immediate"); 623 624 uint32_t TargetOffset = E.getTarget().getAddress() & 0xfff; 625 assert((TargetOffset & 0x7) == 0 && "GOT entry is not 8-byte aligned"); 626 uint32_t EncodedImm = (TargetOffset >> 3) << 10; 627 uint32_t FixedInstr = RawInstr | EncodedImm; 628 *(ulittle32_t *)FixupPtr = FixedInstr; 629 break; 630 } 631 case LDRLiteral19: { 632 assert((FixupAddress & 0x3) == 0 && "LDR is not 32-bit aligned"); 633 assert(E.getAddend() == 0 && "LDRLiteral19 with non-zero addend"); 634 uint32_t RawInstr = *(ulittle32_t *)FixupPtr; 635 assert(RawInstr == 0x58000010 && "RawInstr isn't a 64-bit LDR literal"); 636 int64_t Delta = E.getTarget().getAddress() - FixupAddress; 637 if (Delta & 0x3) 638 return make_error<JITLinkError>("LDR literal target is not 32-bit " 639 "aligned"); 640 if (Delta < -(1 << 20) || Delta > ((1 << 20) - 1)) 641 return targetOutOfRangeError(B, E); 642 643 uint32_t EncodedImm = (static_cast<uint32_t>(Delta) >> 2) << 5; 644 uint32_t FixedInstr = RawInstr | EncodedImm; 645 *(ulittle32_t *)FixupPtr = FixedInstr; 646 break; 647 } 648 case Delta32: 649 case Delta64: 650 case NegDelta32: 651 case NegDelta64: { 652 int64_t Value; 653 if (E.getKind() == Delta32 || E.getKind() == Delta64) 654 Value = E.getTarget().getAddress() - FixupAddress + E.getAddend(); 655 else 656 Value = FixupAddress - E.getTarget().getAddress() + E.getAddend(); 657 658 if (E.getKind() == Delta32 || E.getKind() == NegDelta32) { 659 if (Value < std::numeric_limits<int32_t>::min() || 660 Value > std::numeric_limits<int32_t>::max()) 661 return targetOutOfRangeError(B, E); 662 *(little32_t *)FixupPtr = Value; 663 } else 664 *(little64_t *)FixupPtr = Value; 665 break; 666 } 667 default: 668 llvm_unreachable("Unrecognized edge kind"); 669 } 670 671 return Error::success(); 672 } 673 674 uint64_t NullValue = 0; 675 }; 676 677 Expected<std::unique_ptr<LinkGraph>> 678 createLinkGraphFromMachOObject_arm64(MemoryBufferRef ObjectBuffer) { 679 auto MachOObj = object::ObjectFile::createMachOObjectFile(ObjectBuffer); 680 if (!MachOObj) 681 return MachOObj.takeError(); 682 return MachOLinkGraphBuilder_arm64(**MachOObj).buildGraph(); 683 } 684 685 void link_MachO_arm64(std::unique_ptr<LinkGraph> G, 686 std::unique_ptr<JITLinkContext> Ctx) { 687 688 PassConfiguration Config; 689 690 if (Ctx->shouldAddDefaultTargetPasses(G->getTargetTriple())) { 691 // Add a mark-live pass. 692 if (auto MarkLive = Ctx->getMarkLivePass(G->getTargetTriple())) 693 Config.PrePrunePasses.push_back(std::move(MarkLive)); 694 else 695 Config.PrePrunePasses.push_back(markAllSymbolsLive); 696 697 // Add an in-place GOT/Stubs pass. 698 Config.PostPrunePasses.push_back([](LinkGraph &G) -> Error { 699 MachO_arm64_GOTAndStubsBuilder(G).run(); 700 return Error::success(); 701 }); 702 } 703 704 if (auto Err = Ctx->modifyPassConfig(G->getTargetTriple(), Config)) 705 return Ctx->notifyFailed(std::move(Err)); 706 707 // Construct a JITLinker and run the link function. 708 MachOJITLinker_arm64::link(std::move(Ctx), std::move(G), std::move(Config)); 709 } 710 711 StringRef getMachOARM64RelocationKindName(Edge::Kind R) { 712 switch (R) { 713 case Branch26: 714 return "Branch26"; 715 case Pointer64: 716 return "Pointer64"; 717 case Pointer64Anon: 718 return "Pointer64Anon"; 719 case Page21: 720 return "Page21"; 721 case PageOffset12: 722 return "PageOffset12"; 723 case GOTPage21: 724 return "GOTPage21"; 725 case GOTPageOffset12: 726 return "GOTPageOffset12"; 727 case PointerToGOT: 728 return "PointerToGOT"; 729 case PairedAddend: 730 return "PairedAddend"; 731 case LDRLiteral19: 732 return "LDRLiteral19"; 733 case Delta32: 734 return "Delta32"; 735 case Delta64: 736 return "Delta64"; 737 case NegDelta32: 738 return "NegDelta32"; 739 case NegDelta64: 740 return "NegDelta64"; 741 default: 742 return getGenericEdgeKindName(static_cast<Edge::Kind>(R)); 743 } 744 } 745 746 } // end namespace jitlink 747 } // end namespace llvm 748