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 #include "llvm/ExecutionEngine/JITLink/DWARFRecordSectionSplitter.h" 15 16 #include "MachOLinkGraphBuilder.h" 17 #include "PerGraphGOTAndPLTStubsBuilder.h" 18 19 #define DEBUG_TYPE "jitlink" 20 21 using namespace llvm; 22 using namespace llvm::jitlink; 23 using namespace llvm::jitlink::MachO_arm64_Edges; 24 25 namespace { 26 27 class MachOLinkGraphBuilder_arm64 : public MachOLinkGraphBuilder { 28 public: 29 MachOLinkGraphBuilder_arm64(const object::MachOObjectFile &Obj) 30 : MachOLinkGraphBuilder(Obj, Triple("arm64-apple-darwin"), 31 getMachOARM64RelocationKindName), 32 NumSymbols(Obj.getSymtabLoadCommand().nsyms) {} 33 34 private: 35 static Expected<MachOARM64RelocationKind> 36 getRelocationKind(const MachO::relocation_info &RI) { 37 switch (RI.r_type) { 38 case MachO::ARM64_RELOC_UNSIGNED: 39 if (!RI.r_pcrel) { 40 if (RI.r_length == 3) 41 return RI.r_extern ? Pointer64 : Pointer64Anon; 42 else if (RI.r_length == 2) 43 return Pointer32; 44 } 45 break; 46 case MachO::ARM64_RELOC_SUBTRACTOR: 47 // SUBTRACTOR must be non-pc-rel, extern, with length 2 or 3. 48 // Initially represent SUBTRACTOR relocations with 'Delta<W>'. 49 // They may be turned into NegDelta<W> by parsePairRelocation. 50 if (!RI.r_pcrel && RI.r_extern) { 51 if (RI.r_length == 2) 52 return Delta32; 53 else if (RI.r_length == 3) 54 return Delta64; 55 } 56 break; 57 case MachO::ARM64_RELOC_BRANCH26: 58 if (RI.r_pcrel && RI.r_extern && RI.r_length == 2) 59 return Branch26; 60 break; 61 case MachO::ARM64_RELOC_PAGE21: 62 if (RI.r_pcrel && RI.r_extern && RI.r_length == 2) 63 return Page21; 64 break; 65 case MachO::ARM64_RELOC_PAGEOFF12: 66 if (!RI.r_pcrel && RI.r_extern && RI.r_length == 2) 67 return PageOffset12; 68 break; 69 case MachO::ARM64_RELOC_GOT_LOAD_PAGE21: 70 if (RI.r_pcrel && RI.r_extern && RI.r_length == 2) 71 return GOTPage21; 72 break; 73 case MachO::ARM64_RELOC_GOT_LOAD_PAGEOFF12: 74 if (!RI.r_pcrel && RI.r_extern && RI.r_length == 2) 75 return GOTPageOffset12; 76 break; 77 case MachO::ARM64_RELOC_POINTER_TO_GOT: 78 if (RI.r_pcrel && RI.r_extern && RI.r_length == 2) 79 return PointerToGOT; 80 break; 81 case MachO::ARM64_RELOC_ADDEND: 82 if (!RI.r_pcrel && !RI.r_extern && RI.r_length == 2) 83 return PairedAddend; 84 break; 85 case MachO::ARM64_RELOC_TLVP_LOAD_PAGE21: 86 if (RI.r_pcrel && RI.r_extern && RI.r_length == 2) 87 return TLVPage21; 88 break; 89 case MachO::ARM64_RELOC_TLVP_LOAD_PAGEOFF12: 90 if (!RI.r_pcrel && RI.r_extern && RI.r_length == 2) 91 return TLVPageOffset12; 92 break; 93 } 94 95 return make_error<JITLinkError>( 96 "Unsupported arm64 relocation: address=" + 97 formatv("{0:x8}", RI.r_address) + 98 ", symbolnum=" + formatv("{0:x6}", RI.r_symbolnum) + 99 ", kind=" + formatv("{0:x1}", RI.r_type) + 100 ", pc_rel=" + (RI.r_pcrel ? "true" : "false") + 101 ", extern=" + (RI.r_extern ? "true" : "false") + 102 ", length=" + formatv("{0:d}", RI.r_length)); 103 } 104 105 using PairRelocInfo = 106 std::tuple<MachOARM64RelocationKind, Symbol *, uint64_t>; 107 108 // Parses paired SUBTRACTOR/UNSIGNED relocations and, on success, 109 // returns the edge kind and addend to be used. 110 Expected<PairRelocInfo> 111 parsePairRelocation(Block &BlockToFix, Edge::Kind SubtractorKind, 112 const MachO::relocation_info &SubRI, 113 orc::ExecutorAddr FixupAddress, const char *FixupContent, 114 object::relocation_iterator &UnsignedRelItr, 115 object::relocation_iterator &RelEnd) { 116 using namespace support; 117 118 assert(((SubtractorKind == Delta32 && SubRI.r_length == 2) || 119 (SubtractorKind == Delta64 && SubRI.r_length == 3)) && 120 "Subtractor kind should match length"); 121 assert(SubRI.r_extern && "SUBTRACTOR reloc symbol should be extern"); 122 assert(!SubRI.r_pcrel && "SUBTRACTOR reloc should not be PCRel"); 123 124 if (UnsignedRelItr == RelEnd) 125 return make_error<JITLinkError>("arm64 SUBTRACTOR without paired " 126 "UNSIGNED relocation"); 127 128 auto UnsignedRI = getRelocationInfo(UnsignedRelItr); 129 130 if (SubRI.r_address != UnsignedRI.r_address) 131 return make_error<JITLinkError>("arm64 SUBTRACTOR and paired UNSIGNED " 132 "point to different addresses"); 133 134 if (SubRI.r_length != UnsignedRI.r_length) 135 return make_error<JITLinkError>("length of arm64 SUBTRACTOR and paired " 136 "UNSIGNED reloc must match"); 137 138 Symbol *FromSymbol; 139 if (auto FromSymbolOrErr = findSymbolByIndex(SubRI.r_symbolnum)) 140 FromSymbol = FromSymbolOrErr->GraphSymbol; 141 else 142 return FromSymbolOrErr.takeError(); 143 144 // Read the current fixup value. 145 uint64_t FixupValue = 0; 146 if (SubRI.r_length == 3) 147 FixupValue = *(const little64_t *)FixupContent; 148 else 149 FixupValue = *(const little32_t *)FixupContent; 150 151 // Find 'ToSymbol' using symbol number or address, depending on whether the 152 // paired UNSIGNED relocation is extern. 153 Symbol *ToSymbol = nullptr; 154 if (UnsignedRI.r_extern) { 155 // Find target symbol by symbol index. 156 if (auto ToSymbolOrErr = findSymbolByIndex(UnsignedRI.r_symbolnum)) 157 ToSymbol = ToSymbolOrErr->GraphSymbol; 158 else 159 return ToSymbolOrErr.takeError(); 160 } else { 161 auto ToSymbolSec = findSectionByIndex(UnsignedRI.r_symbolnum - 1); 162 if (!ToSymbolSec) 163 return ToSymbolSec.takeError(); 164 ToSymbol = getSymbolByAddress(*ToSymbolSec, ToSymbolSec->Address); 165 assert(ToSymbol && "No symbol for section"); 166 FixupValue -= ToSymbol->getAddress().getValue(); 167 } 168 169 MachOARM64RelocationKind DeltaKind; 170 Symbol *TargetSymbol; 171 uint64_t Addend; 172 if (&BlockToFix == &FromSymbol->getAddressable()) { 173 TargetSymbol = ToSymbol; 174 DeltaKind = (SubRI.r_length == 3) ? Delta64 : Delta32; 175 Addend = FixupValue + (FixupAddress - FromSymbol->getAddress()); 176 // FIXME: handle extern 'from'. 177 } else if (&BlockToFix == &ToSymbol->getAddressable()) { 178 TargetSymbol = &*FromSymbol; 179 DeltaKind = (SubRI.r_length == 3) ? NegDelta64 : NegDelta32; 180 Addend = FixupValue - (FixupAddress - ToSymbol->getAddress()); 181 } else { 182 // BlockToFix was neither FromSymbol nor ToSymbol. 183 return make_error<JITLinkError>("SUBTRACTOR relocation must fix up " 184 "either 'A' or 'B' (or a symbol in one " 185 "of their alt-entry groups)"); 186 } 187 188 return PairRelocInfo(DeltaKind, TargetSymbol, Addend); 189 } 190 191 Error addRelocations() override { 192 using namespace support; 193 auto &Obj = getObject(); 194 195 LLVM_DEBUG(dbgs() << "Processing relocations:\n"); 196 197 for (auto &S : Obj.sections()) { 198 199 orc::ExecutorAddr SectionAddress(S.getAddress()); 200 201 // Skip relocations virtual sections. 202 if (S.isVirtual()) { 203 if (S.relocation_begin() != S.relocation_end()) 204 return make_error<JITLinkError>("Virtual section contains " 205 "relocations"); 206 continue; 207 } 208 209 auto NSec = 210 findSectionByIndex(Obj.getSectionIndex(S.getRawDataRefImpl())); 211 if (!NSec) 212 return NSec.takeError(); 213 214 // Skip relocations for MachO sections without corresponding graph 215 // sections. 216 { 217 if (!NSec->GraphSection) { 218 LLVM_DEBUG({ 219 dbgs() << " Skipping relocations for MachO section " 220 << NSec->SegName << "/" << NSec->SectName 221 << " which has no associated graph section\n"; 222 }); 223 continue; 224 } 225 } 226 227 for (auto RelItr = S.relocation_begin(), RelEnd = S.relocation_end(); 228 RelItr != RelEnd; ++RelItr) { 229 230 MachO::relocation_info RI = getRelocationInfo(RelItr); 231 232 // Validate the relocation kind. 233 auto Kind = getRelocationKind(RI); 234 if (!Kind) 235 return Kind.takeError(); 236 237 // Find the address of the value to fix up. 238 orc::ExecutorAddr FixupAddress = 239 SectionAddress + (uint32_t)RI.r_address; 240 LLVM_DEBUG({ 241 dbgs() << " " << NSec->SectName << " + " 242 << formatv("{0:x8}", RI.r_address) << ":\n"; 243 }); 244 245 // Find the block that the fixup points to. 246 Block *BlockToFix = nullptr; 247 { 248 auto SymbolToFixOrErr = findSymbolByAddress(*NSec, FixupAddress); 249 if (!SymbolToFixOrErr) 250 return SymbolToFixOrErr.takeError(); 251 BlockToFix = &SymbolToFixOrErr->getBlock(); 252 } 253 254 if (FixupAddress + orc::ExecutorAddrDiff(1ULL << RI.r_length) > 255 BlockToFix->getAddress() + BlockToFix->getContent().size()) 256 return make_error<JITLinkError>( 257 "Relocation content extends past end of fixup block"); 258 259 // Get a pointer to the fixup content. 260 const char *FixupContent = BlockToFix->getContent().data() + 261 (FixupAddress - BlockToFix->getAddress()); 262 263 // The target symbol and addend will be populated by the switch below. 264 Symbol *TargetSymbol = nullptr; 265 uint64_t Addend = 0; 266 267 if (*Kind == PairedAddend) { 268 // If this is an Addend relocation then process it and move to the 269 // paired reloc. 270 271 Addend = SignExtend64(RI.r_symbolnum, 24); 272 273 if (RelItr == RelEnd) 274 return make_error<JITLinkError>("Unpaired Addend reloc at " + 275 formatv("{0:x16}", FixupAddress)); 276 ++RelItr; 277 RI = getRelocationInfo(RelItr); 278 279 Kind = getRelocationKind(RI); 280 if (!Kind) 281 return Kind.takeError(); 282 283 if (*Kind != Branch26 && *Kind != Page21 && *Kind != PageOffset12) 284 return make_error<JITLinkError>( 285 "Invalid relocation pair: Addend + " + 286 StringRef(getMachOARM64RelocationKindName(*Kind))); 287 288 LLVM_DEBUG({ 289 dbgs() << " Addend: value = " << formatv("{0:x6}", Addend) 290 << ", pair is " << getMachOARM64RelocationKindName(*Kind) 291 << "\n"; 292 }); 293 294 // Find the address of the value to fix up. 295 orc::ExecutorAddr PairedFixupAddress = 296 SectionAddress + (uint32_t)RI.r_address; 297 if (PairedFixupAddress != FixupAddress) 298 return make_error<JITLinkError>("Paired relocation points at " 299 "different target"); 300 } 301 302 switch (*Kind) { 303 case Branch26: { 304 if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum)) 305 TargetSymbol = TargetSymbolOrErr->GraphSymbol; 306 else 307 return TargetSymbolOrErr.takeError(); 308 uint32_t Instr = *(const ulittle32_t *)FixupContent; 309 if ((Instr & 0x7fffffff) != 0x14000000) 310 return make_error<JITLinkError>("BRANCH26 target is not a B or BL " 311 "instruction with a zero addend"); 312 break; 313 } 314 case Pointer32: 315 if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum)) 316 TargetSymbol = TargetSymbolOrErr->GraphSymbol; 317 else 318 return TargetSymbolOrErr.takeError(); 319 Addend = *(const ulittle32_t *)FixupContent; 320 break; 321 case Pointer64: 322 if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum)) 323 TargetSymbol = TargetSymbolOrErr->GraphSymbol; 324 else 325 return TargetSymbolOrErr.takeError(); 326 Addend = *(const ulittle64_t *)FixupContent; 327 break; 328 case Pointer64Anon: { 329 orc::ExecutorAddr TargetAddress(*(const ulittle64_t *)FixupContent); 330 auto TargetNSec = findSectionByIndex(RI.r_symbolnum - 1); 331 if (!TargetNSec) 332 return TargetNSec.takeError(); 333 if (auto TargetSymbolOrErr = 334 findSymbolByAddress(*TargetNSec, TargetAddress)) 335 TargetSymbol = &*TargetSymbolOrErr; 336 else 337 return TargetSymbolOrErr.takeError(); 338 Addend = TargetAddress - TargetSymbol->getAddress(); 339 break; 340 } 341 case Page21: 342 case TLVPage21: 343 case GOTPage21: { 344 if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum)) 345 TargetSymbol = TargetSymbolOrErr->GraphSymbol; 346 else 347 return TargetSymbolOrErr.takeError(); 348 uint32_t Instr = *(const ulittle32_t *)FixupContent; 349 if ((Instr & 0xffffffe0) != 0x90000000) 350 return make_error<JITLinkError>("PAGE21/GOTPAGE21 target is not an " 351 "ADRP instruction with a zero " 352 "addend"); 353 break; 354 } 355 case PageOffset12: { 356 if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum)) 357 TargetSymbol = TargetSymbolOrErr->GraphSymbol; 358 else 359 return TargetSymbolOrErr.takeError(); 360 uint32_t Instr = *(const ulittle32_t *)FixupContent; 361 uint32_t EncodedAddend = (Instr & 0x003FFC00) >> 10; 362 if (EncodedAddend != 0) 363 return make_error<JITLinkError>("GOTPAGEOFF12 target has non-zero " 364 "encoded addend"); 365 break; 366 } 367 case TLVPageOffset12: 368 case GOTPageOffset12: { 369 if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum)) 370 TargetSymbol = TargetSymbolOrErr->GraphSymbol; 371 else 372 return TargetSymbolOrErr.takeError(); 373 uint32_t Instr = *(const ulittle32_t *)FixupContent; 374 if ((Instr & 0xfffffc00) != 0xf9400000) 375 return make_error<JITLinkError>("GOTPAGEOFF12 target is not an LDR " 376 "immediate instruction with a zero " 377 "addend"); 378 break; 379 } 380 case PointerToGOT: 381 if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum)) 382 TargetSymbol = TargetSymbolOrErr->GraphSymbol; 383 else 384 return TargetSymbolOrErr.takeError(); 385 break; 386 case Delta32: 387 case Delta64: { 388 // We use Delta32/Delta64 to represent SUBTRACTOR relocations. 389 // parsePairRelocation handles the paired reloc, and returns the 390 // edge kind to be used (either Delta32/Delta64, or 391 // NegDelta32/NegDelta64, depending on the direction of the 392 // subtraction) along with the addend. 393 auto PairInfo = 394 parsePairRelocation(*BlockToFix, *Kind, RI, FixupAddress, 395 FixupContent, ++RelItr, RelEnd); 396 if (!PairInfo) 397 return PairInfo.takeError(); 398 std::tie(*Kind, TargetSymbol, Addend) = *PairInfo; 399 assert(TargetSymbol && "No target symbol from parsePairRelocation?"); 400 break; 401 } 402 default: 403 llvm_unreachable("Special relocation kind should not appear in " 404 "mach-o file"); 405 } 406 407 LLVM_DEBUG({ 408 dbgs() << " "; 409 Edge GE(*Kind, FixupAddress - BlockToFix->getAddress(), *TargetSymbol, 410 Addend); 411 printEdge(dbgs(), *BlockToFix, GE, 412 getMachOARM64RelocationKindName(*Kind)); 413 dbgs() << "\n"; 414 }); 415 BlockToFix->addEdge(*Kind, FixupAddress - BlockToFix->getAddress(), 416 *TargetSymbol, Addend); 417 } 418 } 419 return Error::success(); 420 } 421 422 unsigned NumSymbols = 0; 423 }; 424 425 class PerGraphGOTAndPLTStubsBuilder_MachO_arm64 426 : public PerGraphGOTAndPLTStubsBuilder< 427 PerGraphGOTAndPLTStubsBuilder_MachO_arm64> { 428 public: 429 using PerGraphGOTAndPLTStubsBuilder< 430 PerGraphGOTAndPLTStubsBuilder_MachO_arm64>::PerGraphGOTAndPLTStubsBuilder; 431 432 bool isGOTEdgeToFix(Edge &E) const { 433 return E.getKind() == GOTPage21 || E.getKind() == GOTPageOffset12 || 434 E.getKind() == TLVPage21 || E.getKind() == TLVPageOffset12 || 435 E.getKind() == PointerToGOT; 436 } 437 438 Symbol &createGOTEntry(Symbol &Target) { 439 auto &GOTEntryBlock = G.createContentBlock( 440 getGOTSection(), getGOTEntryBlockContent(), orc::ExecutorAddr(), 8, 0); 441 GOTEntryBlock.addEdge(Pointer64, 0, Target, 0); 442 return G.addAnonymousSymbol(GOTEntryBlock, 0, 8, false, false); 443 } 444 445 void fixGOTEdge(Edge &E, Symbol &GOTEntry) { 446 if (E.getKind() == GOTPage21 || E.getKind() == GOTPageOffset12 || 447 E.getKind() == TLVPage21 || E.getKind() == TLVPageOffset12) { 448 // Update the target, but leave the edge addend as-is. 449 E.setTarget(GOTEntry); 450 } else if (E.getKind() == PointerToGOT) { 451 E.setTarget(GOTEntry); 452 E.setKind(Delta32); 453 } else 454 llvm_unreachable("Not a GOT edge?"); 455 } 456 457 bool isExternalBranchEdge(Edge &E) { 458 return E.getKind() == Branch26 && !E.getTarget().isDefined(); 459 } 460 461 Symbol &createPLTStub(Symbol &Target) { 462 auto &StubContentBlock = G.createContentBlock( 463 getStubsSection(), getStubBlockContent(), orc::ExecutorAddr(), 1, 0); 464 // Re-use GOT entries for stub targets. 465 auto &GOTEntrySymbol = getGOTEntry(Target); 466 StubContentBlock.addEdge(LDRLiteral19, 0, GOTEntrySymbol, 0); 467 return G.addAnonymousSymbol(StubContentBlock, 0, 8, true, false); 468 } 469 470 void fixPLTEdge(Edge &E, Symbol &Stub) { 471 assert(E.getKind() == Branch26 && "Not a Branch32 edge?"); 472 assert(E.getAddend() == 0 && "Branch32 edge has non-zero addend?"); 473 E.setTarget(Stub); 474 } 475 476 private: 477 Section &getGOTSection() { 478 if (!GOTSection) 479 GOTSection = &G.createSection("$__GOT", MemProt::Read | MemProt::Exec); 480 return *GOTSection; 481 } 482 483 Section &getStubsSection() { 484 if (!StubsSection) 485 StubsSection = 486 &G.createSection("$__STUBS", MemProt::Read | MemProt::Exec); 487 return *StubsSection; 488 } 489 490 ArrayRef<char> getGOTEntryBlockContent() { 491 return {reinterpret_cast<const char *>(NullGOTEntryContent), 492 sizeof(NullGOTEntryContent)}; 493 } 494 495 ArrayRef<char> getStubBlockContent() { 496 return {reinterpret_cast<const char *>(StubContent), sizeof(StubContent)}; 497 } 498 499 static const uint8_t NullGOTEntryContent[8]; 500 static const uint8_t StubContent[8]; 501 Section *GOTSection = nullptr; 502 Section *StubsSection = nullptr; 503 }; 504 505 const uint8_t 506 PerGraphGOTAndPLTStubsBuilder_MachO_arm64::NullGOTEntryContent[8] = { 507 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}; 508 const uint8_t PerGraphGOTAndPLTStubsBuilder_MachO_arm64::StubContent[8] = { 509 0x10, 0x00, 0x00, 0x58, // LDR x16, <literal> 510 0x00, 0x02, 0x1f, 0xd6 // BR x16 511 }; 512 513 } // namespace 514 515 namespace llvm { 516 namespace jitlink { 517 518 class MachOJITLinker_arm64 : public JITLinker<MachOJITLinker_arm64> { 519 friend class JITLinker<MachOJITLinker_arm64>; 520 521 public: 522 MachOJITLinker_arm64(std::unique_ptr<JITLinkContext> Ctx, 523 std::unique_ptr<LinkGraph> G, 524 PassConfiguration PassConfig) 525 : JITLinker(std::move(Ctx), std::move(G), std::move(PassConfig)) {} 526 527 private: 528 529 static unsigned getPageOffset12Shift(uint32_t Instr) { 530 constexpr uint32_t LoadStoreImm12Mask = 0x3b000000; 531 constexpr uint32_t Vec128Mask = 0x04800000; 532 533 if ((Instr & LoadStoreImm12Mask) == 0x39000000) { 534 uint32_t ImplicitShift = Instr >> 30; 535 if (ImplicitShift == 0) 536 if ((Instr & Vec128Mask) == Vec128Mask) 537 ImplicitShift = 4; 538 539 return ImplicitShift; 540 } 541 542 return 0; 543 } 544 545 Error applyFixup(LinkGraph &G, Block &B, const Edge &E) const { 546 using namespace support; 547 548 char *BlockWorkingMem = B.getAlreadyMutableContent().data(); 549 char *FixupPtr = BlockWorkingMem + E.getOffset(); 550 orc::ExecutorAddr FixupAddress = B.getAddress() + E.getOffset(); 551 552 switch (E.getKind()) { 553 case Branch26: { 554 assert((FixupAddress.getValue() & 0x3) == 0 && 555 "Branch-inst is not 32-bit aligned"); 556 557 int64_t Value = E.getTarget().getAddress() - FixupAddress + E.getAddend(); 558 559 if (static_cast<uint64_t>(Value) & 0x3) 560 return make_error<JITLinkError>("Branch26 target is not 32-bit " 561 "aligned"); 562 563 if (Value < -(1 << 27) || Value > ((1 << 27) - 1)) 564 return makeTargetOutOfRangeError(G, B, E); 565 566 uint32_t RawInstr = *(little32_t *)FixupPtr; 567 assert((RawInstr & 0x7fffffff) == 0x14000000 && 568 "RawInstr isn't a B or BR immediate instruction"); 569 uint32_t Imm = (static_cast<uint32_t>(Value) & ((1 << 28) - 1)) >> 2; 570 uint32_t FixedInstr = RawInstr | Imm; 571 *(little32_t *)FixupPtr = FixedInstr; 572 break; 573 } 574 case Pointer32: { 575 uint64_t Value = E.getTarget().getAddress().getValue() + E.getAddend(); 576 if (Value > std::numeric_limits<uint32_t>::max()) 577 return makeTargetOutOfRangeError(G, B, E); 578 *(ulittle32_t *)FixupPtr = Value; 579 break; 580 } 581 case Pointer64: 582 case Pointer64Anon: { 583 uint64_t Value = E.getTarget().getAddress().getValue() + E.getAddend(); 584 *(ulittle64_t *)FixupPtr = Value; 585 break; 586 } 587 case Page21: 588 case TLVPage21: 589 case GOTPage21: { 590 assert((E.getKind() != GOTPage21 || E.getAddend() == 0) && 591 "GOTPAGE21 with non-zero addend"); 592 uint64_t TargetPage = 593 (E.getTarget().getAddress().getValue() + E.getAddend()) & 594 ~static_cast<uint64_t>(4096 - 1); 595 uint64_t PCPage = 596 FixupAddress.getValue() & ~static_cast<uint64_t>(4096 - 1); 597 598 int64_t PageDelta = TargetPage - PCPage; 599 if (PageDelta < -(1 << 30) || PageDelta > ((1 << 30) - 1)) 600 return makeTargetOutOfRangeError(G, B, E); 601 602 uint32_t RawInstr = *(ulittle32_t *)FixupPtr; 603 assert((RawInstr & 0xffffffe0) == 0x90000000 && 604 "RawInstr isn't an ADRP instruction"); 605 uint32_t ImmLo = (static_cast<uint64_t>(PageDelta) >> 12) & 0x3; 606 uint32_t ImmHi = (static_cast<uint64_t>(PageDelta) >> 14) & 0x7ffff; 607 uint32_t FixedInstr = RawInstr | (ImmLo << 29) | (ImmHi << 5); 608 *(ulittle32_t *)FixupPtr = FixedInstr; 609 break; 610 } 611 case PageOffset12: { 612 uint64_t TargetOffset = 613 (E.getTarget().getAddress() + E.getAddend()).getValue() & 0xfff; 614 615 uint32_t RawInstr = *(ulittle32_t *)FixupPtr; 616 unsigned ImmShift = getPageOffset12Shift(RawInstr); 617 618 if (TargetOffset & ((1 << ImmShift) - 1)) 619 return make_error<JITLinkError>("PAGEOFF12 target is not aligned"); 620 621 uint32_t EncodedImm = (TargetOffset >> ImmShift) << 10; 622 uint32_t FixedInstr = RawInstr | EncodedImm; 623 *(ulittle32_t *)FixupPtr = FixedInstr; 624 break; 625 } 626 case TLVPageOffset12: 627 case GOTPageOffset12: { 628 assert(E.getAddend() == 0 && "GOTPAGEOF12 with non-zero addend"); 629 630 uint32_t RawInstr = *(ulittle32_t *)FixupPtr; 631 assert((RawInstr & 0xfffffc00) == 0xf9400000 && 632 "RawInstr isn't a 64-bit LDR immediate"); 633 634 uint32_t TargetOffset = E.getTarget().getAddress().getValue() & 0xfff; 635 assert((TargetOffset & 0x7) == 0 && "GOT entry is not 8-byte aligned"); 636 uint32_t EncodedImm = (TargetOffset >> 3) << 10; 637 uint32_t FixedInstr = RawInstr | EncodedImm; 638 *(ulittle32_t *)FixupPtr = FixedInstr; 639 break; 640 } 641 case LDRLiteral19: { 642 assert((FixupAddress.getValue() & 0x3) == 0 && 643 "LDR is not 32-bit aligned"); 644 assert(E.getAddend() == 0 && "LDRLiteral19 with non-zero addend"); 645 uint32_t RawInstr = *(ulittle32_t *)FixupPtr; 646 assert(RawInstr == 0x58000010 && "RawInstr isn't a 64-bit LDR literal"); 647 int64_t Delta = E.getTarget().getAddress() - FixupAddress; 648 if (Delta & 0x3) 649 return make_error<JITLinkError>("LDR literal target is not 32-bit " 650 "aligned"); 651 if (Delta < -(1 << 20) || Delta > ((1 << 20) - 1)) 652 return makeTargetOutOfRangeError(G, B, E); 653 654 uint32_t EncodedImm = 655 ((static_cast<uint32_t>(Delta) >> 2) & 0x7ffff) << 5; 656 uint32_t FixedInstr = RawInstr | EncodedImm; 657 *(ulittle32_t *)FixupPtr = FixedInstr; 658 break; 659 } 660 case Delta32: 661 case Delta64: 662 case NegDelta32: 663 case NegDelta64: { 664 int64_t Value; 665 if (E.getKind() == Delta32 || E.getKind() == Delta64) 666 Value = E.getTarget().getAddress() - FixupAddress + E.getAddend(); 667 else 668 Value = FixupAddress - E.getTarget().getAddress() + E.getAddend(); 669 670 if (E.getKind() == Delta32 || E.getKind() == NegDelta32) { 671 if (Value < std::numeric_limits<int32_t>::min() || 672 Value > std::numeric_limits<int32_t>::max()) 673 return makeTargetOutOfRangeError(G, B, E); 674 *(little32_t *)FixupPtr = Value; 675 } else 676 *(little64_t *)FixupPtr = Value; 677 break; 678 } 679 default: 680 llvm_unreachable("Unrecognized edge kind"); 681 } 682 683 return Error::success(); 684 } 685 686 uint64_t NullValue = 0; 687 }; 688 689 Expected<std::unique_ptr<LinkGraph>> 690 createLinkGraphFromMachOObject_arm64(MemoryBufferRef ObjectBuffer) { 691 auto MachOObj = object::ObjectFile::createMachOObjectFile(ObjectBuffer); 692 if (!MachOObj) 693 return MachOObj.takeError(); 694 return MachOLinkGraphBuilder_arm64(**MachOObj).buildGraph(); 695 } 696 697 void link_MachO_arm64(std::unique_ptr<LinkGraph> G, 698 std::unique_ptr<JITLinkContext> Ctx) { 699 700 PassConfiguration Config; 701 702 if (Ctx->shouldAddDefaultTargetPasses(G->getTargetTriple())) { 703 // Add a mark-live pass. 704 if (auto MarkLive = Ctx->getMarkLivePass(G->getTargetTriple())) 705 Config.PrePrunePasses.push_back(std::move(MarkLive)); 706 else 707 Config.PrePrunePasses.push_back(markAllSymbolsLive); 708 709 // Add compact unwind splitter pass. 710 Config.PrePrunePasses.push_back( 711 CompactUnwindSplitter("__LD,__compact_unwind")); 712 713 // Add eh-frame passses. 714 // FIXME: Prune eh-frames for which compact-unwind is available once 715 // we support compact-unwind registration with libunwind. 716 Config.PrePrunePasses.push_back( 717 DWARFRecordSectionSplitter("__TEXT,__eh_frame")); 718 Config.PrePrunePasses.push_back( 719 EHFrameEdgeFixer("__TEXT,__eh_frame", 8, Delta64, Delta32, NegDelta32)); 720 721 // Add an in-place GOT/Stubs pass. 722 Config.PostPrunePasses.push_back( 723 PerGraphGOTAndPLTStubsBuilder_MachO_arm64::asPass); 724 } 725 726 if (auto Err = Ctx->modifyPassConfig(*G, Config)) 727 return Ctx->notifyFailed(std::move(Err)); 728 729 // Construct a JITLinker and run the link function. 730 MachOJITLinker_arm64::link(std::move(Ctx), std::move(G), std::move(Config)); 731 } 732 733 const char *getMachOARM64RelocationKindName(Edge::Kind R) { 734 switch (R) { 735 case Branch26: 736 return "Branch26"; 737 case Pointer64: 738 return "Pointer64"; 739 case Pointer64Anon: 740 return "Pointer64Anon"; 741 case Page21: 742 return "Page21"; 743 case PageOffset12: 744 return "PageOffset12"; 745 case GOTPage21: 746 return "GOTPage21"; 747 case GOTPageOffset12: 748 return "GOTPageOffset12"; 749 case TLVPage21: 750 return "TLVPage21"; 751 case TLVPageOffset12: 752 return "TLVPageOffset12"; 753 case PointerToGOT: 754 return "PointerToGOT"; 755 case PairedAddend: 756 return "PairedAddend"; 757 case LDRLiteral19: 758 return "LDRLiteral19"; 759 case Delta32: 760 return "Delta32"; 761 case Delta64: 762 return "Delta64"; 763 case NegDelta32: 764 return "NegDelta32"; 765 case NegDelta64: 766 return "NegDelta64"; 767 default: 768 return getGenericEdgeKindName(static_cast<Edge::Kind>(R)); 769 } 770 } 771 772 } // end namespace jitlink 773 } // end namespace llvm 774