| //===---- MachO_arm64.cpp - JIT linker implementation for MachO/arm64 -----===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // MachO/arm64 jit-link implementation. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "llvm/ExecutionEngine/JITLink/MachO_arm64.h" |
| |
| #include "MachOLinkGraphBuilder.h" |
| #include "PerGraphGOTAndPLTStubsBuilder.h" |
| |
| #define DEBUG_TYPE "jitlink" |
| |
| using namespace llvm; |
| using namespace llvm::jitlink; |
| using namespace llvm::jitlink::MachO_arm64_Edges; |
| |
| namespace { |
| |
| class MachOLinkGraphBuilder_arm64 : public MachOLinkGraphBuilder { |
| public: |
| MachOLinkGraphBuilder_arm64(const object::MachOObjectFile &Obj) |
| : MachOLinkGraphBuilder(Obj, Triple("arm64-apple-darwin"), |
| getMachOARM64RelocationKindName), |
| NumSymbols(Obj.getSymtabLoadCommand().nsyms) {} |
| |
| private: |
| static Expected<MachOARM64RelocationKind> |
| getRelocationKind(const MachO::relocation_info &RI) { |
| switch (RI.r_type) { |
| case MachO::ARM64_RELOC_UNSIGNED: |
| if (!RI.r_pcrel) { |
| if (RI.r_length == 3) |
| return RI.r_extern ? Pointer64 : Pointer64Anon; |
| else if (RI.r_length == 2) |
| return Pointer32; |
| } |
| break; |
| case MachO::ARM64_RELOC_SUBTRACTOR: |
| // SUBTRACTOR must be non-pc-rel, extern, with length 2 or 3. |
| // Initially represent SUBTRACTOR relocations with 'Delta<W>'. |
| // They may be turned into NegDelta<W> by parsePairRelocation. |
| if (!RI.r_pcrel && RI.r_extern) { |
| if (RI.r_length == 2) |
| return Delta32; |
| else if (RI.r_length == 3) |
| return Delta64; |
| } |
| break; |
| case MachO::ARM64_RELOC_BRANCH26: |
| if (RI.r_pcrel && RI.r_extern && RI.r_length == 2) |
| return Branch26; |
| break; |
| case MachO::ARM64_RELOC_PAGE21: |
| if (RI.r_pcrel && RI.r_extern && RI.r_length == 2) |
| return Page21; |
| break; |
| case MachO::ARM64_RELOC_PAGEOFF12: |
| if (!RI.r_pcrel && RI.r_extern && RI.r_length == 2) |
| return PageOffset12; |
| break; |
| case MachO::ARM64_RELOC_GOT_LOAD_PAGE21: |
| if (RI.r_pcrel && RI.r_extern && RI.r_length == 2) |
| return GOTPage21; |
| break; |
| case MachO::ARM64_RELOC_GOT_LOAD_PAGEOFF12: |
| if (!RI.r_pcrel && RI.r_extern && RI.r_length == 2) |
| return GOTPageOffset12; |
| break; |
| case MachO::ARM64_RELOC_POINTER_TO_GOT: |
| if (RI.r_pcrel && RI.r_extern && RI.r_length == 2) |
| return PointerToGOT; |
| break; |
| case MachO::ARM64_RELOC_ADDEND: |
| if (!RI.r_pcrel && !RI.r_extern && RI.r_length == 2) |
| return PairedAddend; |
| break; |
| } |
| |
| return make_error<JITLinkError>( |
| "Unsupported arm64 relocation: address=" + |
| formatv("{0:x8}", RI.r_address) + |
| ", symbolnum=" + formatv("{0:x6}", RI.r_symbolnum) + |
| ", kind=" + formatv("{0:x1}", RI.r_type) + |
| ", pc_rel=" + (RI.r_pcrel ? "true" : "false") + |
| ", extern=" + (RI.r_extern ? "true" : "false") + |
| ", length=" + formatv("{0:d}", RI.r_length)); |
| } |
| |
| using PairRelocInfo = |
| std::tuple<MachOARM64RelocationKind, Symbol *, uint64_t>; |
| |
| // Parses paired SUBTRACTOR/UNSIGNED relocations and, on success, |
| // returns the edge kind and addend to be used. |
| Expected<PairRelocInfo> |
| parsePairRelocation(Block &BlockToFix, Edge::Kind SubtractorKind, |
| const MachO::relocation_info &SubRI, |
| JITTargetAddress FixupAddress, const char *FixupContent, |
| object::relocation_iterator &UnsignedRelItr, |
| object::relocation_iterator &RelEnd) { |
| using namespace support; |
| |
| assert(((SubtractorKind == Delta32 && SubRI.r_length == 2) || |
| (SubtractorKind == Delta64 && SubRI.r_length == 3)) && |
| "Subtractor kind should match length"); |
| assert(SubRI.r_extern && "SUBTRACTOR reloc symbol should be extern"); |
| assert(!SubRI.r_pcrel && "SUBTRACTOR reloc should not be PCRel"); |
| |
| if (UnsignedRelItr == RelEnd) |
| return make_error<JITLinkError>("arm64 SUBTRACTOR without paired " |
| "UNSIGNED relocation"); |
| |
| auto UnsignedRI = getRelocationInfo(UnsignedRelItr); |
| |
| if (SubRI.r_address != UnsignedRI.r_address) |
| return make_error<JITLinkError>("arm64 SUBTRACTOR and paired UNSIGNED " |
| "point to different addresses"); |
| |
| if (SubRI.r_length != UnsignedRI.r_length) |
| return make_error<JITLinkError>("length of arm64 SUBTRACTOR and paired " |
| "UNSIGNED reloc must match"); |
| |
| Symbol *FromSymbol; |
| if (auto FromSymbolOrErr = findSymbolByIndex(SubRI.r_symbolnum)) |
| FromSymbol = FromSymbolOrErr->GraphSymbol; |
| else |
| return FromSymbolOrErr.takeError(); |
| |
| // Read the current fixup value. |
| uint64_t FixupValue = 0; |
| if (SubRI.r_length == 3) |
| FixupValue = *(const little64_t *)FixupContent; |
| else |
| FixupValue = *(const little32_t *)FixupContent; |
| |
| // Find 'ToSymbol' using symbol number or address, depending on whether the |
| // paired UNSIGNED relocation is extern. |
| Symbol *ToSymbol = nullptr; |
| if (UnsignedRI.r_extern) { |
| // Find target symbol by symbol index. |
| if (auto ToSymbolOrErr = findSymbolByIndex(UnsignedRI.r_symbolnum)) |
| ToSymbol = ToSymbolOrErr->GraphSymbol; |
| else |
| return ToSymbolOrErr.takeError(); |
| } else { |
| auto ToSymbolSec = findSectionByIndex(UnsignedRI.r_symbolnum - 1); |
| if (!ToSymbolSec) |
| return ToSymbolSec.takeError(); |
| ToSymbol = getSymbolByAddress(ToSymbolSec->Address); |
| assert(ToSymbol && "No symbol for section"); |
| FixupValue -= ToSymbol->getAddress(); |
| } |
| |
| MachOARM64RelocationKind DeltaKind; |
| Symbol *TargetSymbol; |
| uint64_t Addend; |
| if (&BlockToFix == &FromSymbol->getAddressable()) { |
| TargetSymbol = ToSymbol; |
| DeltaKind = (SubRI.r_length == 3) ? Delta64 : Delta32; |
| Addend = FixupValue + (FixupAddress - FromSymbol->getAddress()); |
| // FIXME: handle extern 'from'. |
| } else if (&BlockToFix == &ToSymbol->getAddressable()) { |
| TargetSymbol = &*FromSymbol; |
| DeltaKind = (SubRI.r_length == 3) ? NegDelta64 : NegDelta32; |
| Addend = FixupValue - (FixupAddress - ToSymbol->getAddress()); |
| } else { |
| // BlockToFix was neither FromSymbol nor ToSymbol. |
| return make_error<JITLinkError>("SUBTRACTOR relocation must fix up " |
| "either 'A' or 'B' (or a symbol in one " |
| "of their alt-entry groups)"); |
| } |
| |
| return PairRelocInfo(DeltaKind, TargetSymbol, Addend); |
| } |
| |
| Error addRelocations() override { |
| using namespace support; |
| auto &Obj = getObject(); |
| |
| LLVM_DEBUG(dbgs() << "Processing relocations:\n"); |
| |
| for (auto &S : Obj.sections()) { |
| |
| JITTargetAddress SectionAddress = S.getAddress(); |
| |
| // Skip relocations virtual sections. |
| if (S.isVirtual()) { |
| if (S.relocation_begin() != S.relocation_end()) |
| return make_error<JITLinkError>("Virtual section contains " |
| "relocations"); |
| continue; |
| } |
| |
| // Skip relocations for debug symbols. |
| { |
| auto &NSec = |
| getSectionByIndex(Obj.getSectionIndex(S.getRawDataRefImpl())); |
| if (!NSec.GraphSection) { |
| LLVM_DEBUG({ |
| dbgs() << " Skipping relocations for MachO section " |
| << NSec.SegName << "/" << NSec.SectName |
| << " which has no associated graph section\n"; |
| }); |
| continue; |
| } |
| } |
| |
| for (auto RelItr = S.relocation_begin(), RelEnd = S.relocation_end(); |
| RelItr != RelEnd; ++RelItr) { |
| |
| MachO::relocation_info RI = getRelocationInfo(RelItr); |
| |
| // Sanity check the relocation kind. |
| auto Kind = getRelocationKind(RI); |
| if (!Kind) |
| return Kind.takeError(); |
| |
| // Find the address of the value to fix up. |
| JITTargetAddress FixupAddress = SectionAddress + (uint32_t)RI.r_address; |
| |
| LLVM_DEBUG({ |
| auto &NSec = |
| getSectionByIndex(Obj.getSectionIndex(S.getRawDataRefImpl())); |
| dbgs() << " " << NSec.SectName << " + " |
| << formatv("{0:x8}", RI.r_address) << ":\n"; |
| }); |
| |
| // Find the block that the fixup points to. |
| Block *BlockToFix = nullptr; |
| { |
| auto SymbolToFixOrErr = findSymbolByAddress(FixupAddress); |
| if (!SymbolToFixOrErr) |
| return SymbolToFixOrErr.takeError(); |
| BlockToFix = &SymbolToFixOrErr->getBlock(); |
| } |
| |
| if (FixupAddress + static_cast<JITTargetAddress>(1ULL << RI.r_length) > |
| BlockToFix->getAddress() + BlockToFix->getContent().size()) |
| return make_error<JITLinkError>( |
| "Relocation content extends past end of fixup block"); |
| |
| // Get a pointer to the fixup content. |
| const char *FixupContent = BlockToFix->getContent().data() + |
| (FixupAddress - BlockToFix->getAddress()); |
| |
| // The target symbol and addend will be populated by the switch below. |
| Symbol *TargetSymbol = nullptr; |
| uint64_t Addend = 0; |
| |
| if (*Kind == PairedAddend) { |
| // If this is an Addend relocation then process it and move to the |
| // paired reloc. |
| |
| Addend = SignExtend64(RI.r_symbolnum, 24); |
| |
| if (RelItr == RelEnd) |
| return make_error<JITLinkError>("Unpaired Addend reloc at " + |
| formatv("{0:x16}", FixupAddress)); |
| ++RelItr; |
| RI = getRelocationInfo(RelItr); |
| |
| Kind = getRelocationKind(RI); |
| if (!Kind) |
| return Kind.takeError(); |
| |
| if (*Kind != Branch26 && *Kind != Page21 && *Kind != PageOffset12) |
| return make_error<JITLinkError>( |
| "Invalid relocation pair: Addend + " + |
| StringRef(getMachOARM64RelocationKindName(*Kind))); |
| |
| LLVM_DEBUG({ |
| dbgs() << " Addend: value = " << formatv("{0:x6}", Addend) |
| << ", pair is " << getMachOARM64RelocationKindName(*Kind) |
| << "\n"; |
| }); |
| |
| // Find the address of the value to fix up. |
| JITTargetAddress PairedFixupAddress = |
| SectionAddress + (uint32_t)RI.r_address; |
| if (PairedFixupAddress != FixupAddress) |
| return make_error<JITLinkError>("Paired relocation points at " |
| "different target"); |
| } |
| |
| switch (*Kind) { |
| case Branch26: { |
| if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum)) |
| TargetSymbol = TargetSymbolOrErr->GraphSymbol; |
| else |
| return TargetSymbolOrErr.takeError(); |
| uint32_t Instr = *(const ulittle32_t *)FixupContent; |
| if ((Instr & 0x7fffffff) != 0x14000000) |
| return make_error<JITLinkError>("BRANCH26 target is not a B or BL " |
| "instruction with a zero addend"); |
| break; |
| } |
| case Pointer32: |
| if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum)) |
| TargetSymbol = TargetSymbolOrErr->GraphSymbol; |
| else |
| return TargetSymbolOrErr.takeError(); |
| Addend = *(const ulittle32_t *)FixupContent; |
| break; |
| case Pointer64: |
| if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum)) |
| TargetSymbol = TargetSymbolOrErr->GraphSymbol; |
| else |
| return TargetSymbolOrErr.takeError(); |
| Addend = *(const ulittle64_t *)FixupContent; |
| break; |
| case Pointer64Anon: { |
| JITTargetAddress TargetAddress = *(const ulittle64_t *)FixupContent; |
| if (auto TargetSymbolOrErr = findSymbolByAddress(TargetAddress)) |
| TargetSymbol = &*TargetSymbolOrErr; |
| else |
| return TargetSymbolOrErr.takeError(); |
| Addend = TargetAddress - TargetSymbol->getAddress(); |
| break; |
| } |
| case Page21: |
| case GOTPage21: { |
| if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum)) |
| TargetSymbol = TargetSymbolOrErr->GraphSymbol; |
| else |
| return TargetSymbolOrErr.takeError(); |
| uint32_t Instr = *(const ulittle32_t *)FixupContent; |
| if ((Instr & 0xffffffe0) != 0x90000000) |
| return make_error<JITLinkError>("PAGE21/GOTPAGE21 target is not an " |
| "ADRP instruction with a zero " |
| "addend"); |
| break; |
| } |
| case PageOffset12: { |
| if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum)) |
| TargetSymbol = TargetSymbolOrErr->GraphSymbol; |
| else |
| return TargetSymbolOrErr.takeError(); |
| uint32_t Instr = *(const ulittle32_t *)FixupContent; |
| uint32_t EncodedAddend = (Instr & 0x003FFC00) >> 10; |
| if (EncodedAddend != 0) |
| return make_error<JITLinkError>("GOTPAGEOFF12 target has non-zero " |
| "encoded addend"); |
| break; |
| } |
| case GOTPageOffset12: { |
| if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum)) |
| TargetSymbol = TargetSymbolOrErr->GraphSymbol; |
| else |
| return TargetSymbolOrErr.takeError(); |
| uint32_t Instr = *(const ulittle32_t *)FixupContent; |
| if ((Instr & 0xfffffc00) != 0xf9400000) |
| return make_error<JITLinkError>("GOTPAGEOFF12 target is not an LDR " |
| "immediate instruction with a zero " |
| "addend"); |
| break; |
| } |
| case PointerToGOT: |
| if (auto TargetSymbolOrErr = findSymbolByIndex(RI.r_symbolnum)) |
| TargetSymbol = TargetSymbolOrErr->GraphSymbol; |
| else |
| return TargetSymbolOrErr.takeError(); |
| break; |
| case Delta32: |
| case Delta64: { |
| // We use Delta32/Delta64 to represent SUBTRACTOR relocations. |
| // parsePairRelocation handles the paired reloc, and returns the |
| // edge kind to be used (either Delta32/Delta64, or |
| // NegDelta32/NegDelta64, depending on the direction of the |
| // subtraction) along with the addend. |
| auto PairInfo = |
| parsePairRelocation(*BlockToFix, *Kind, RI, FixupAddress, |
| FixupContent, ++RelItr, RelEnd); |
| if (!PairInfo) |
| return PairInfo.takeError(); |
| std::tie(*Kind, TargetSymbol, Addend) = *PairInfo; |
| assert(TargetSymbol && "No target symbol from parsePairRelocation?"); |
| break; |
| } |
| default: |
| llvm_unreachable("Special relocation kind should not appear in " |
| "mach-o file"); |
| } |
| |
| LLVM_DEBUG({ |
| dbgs() << " "; |
| Edge GE(*Kind, FixupAddress - BlockToFix->getAddress(), *TargetSymbol, |
| Addend); |
| printEdge(dbgs(), *BlockToFix, GE, |
| getMachOARM64RelocationKindName(*Kind)); |
| dbgs() << "\n"; |
| }); |
| BlockToFix->addEdge(*Kind, FixupAddress - BlockToFix->getAddress(), |
| *TargetSymbol, Addend); |
| } |
| } |
| return Error::success(); |
| } |
| |
| unsigned NumSymbols = 0; |
| }; |
| |
| class PerGraphGOTAndPLTStubsBuilder_MachO_arm64 |
| : public PerGraphGOTAndPLTStubsBuilder< |
| PerGraphGOTAndPLTStubsBuilder_MachO_arm64> { |
| public: |
| using PerGraphGOTAndPLTStubsBuilder< |
| PerGraphGOTAndPLTStubsBuilder_MachO_arm64>::PerGraphGOTAndPLTStubsBuilder; |
| |
| bool isGOTEdgeToFix(Edge &E) const { |
| return (E.getKind() == GOTPage21 || E.getKind() == GOTPageOffset12 || |
| E.getKind() == PointerToGOT) && |
| E.getTarget().isExternal(); |
| } |
| |
| Symbol &createGOTEntry(Symbol &Target) { |
| auto &GOTEntryBlock = G.createContentBlock( |
| getGOTSection(), getGOTEntryBlockContent(), 0, 8, 0); |
| GOTEntryBlock.addEdge(Pointer64, 0, Target, 0); |
| return G.addAnonymousSymbol(GOTEntryBlock, 0, 8, false, false); |
| } |
| |
| void fixGOTEdge(Edge &E, Symbol &GOTEntry) { |
| if (E.getKind() == GOTPage21 || E.getKind() == GOTPageOffset12) { |
| // Update the target, but leave the edge addend as-is. |
| E.setTarget(GOTEntry); |
| } else if (E.getKind() == PointerToGOT) { |
| E.setTarget(GOTEntry); |
| E.setKind(Delta32); |
| } else |
| llvm_unreachable("Not a GOT edge?"); |
| } |
| |
| bool isExternalBranchEdge(Edge &E) { |
| return E.getKind() == Branch26 && !E.getTarget().isDefined(); |
| } |
| |
| Symbol &createPLTStub(Symbol &Target) { |
| auto &StubContentBlock = |
| G.createContentBlock(getStubsSection(), getStubBlockContent(), 0, 1, 0); |
| // Re-use GOT entries for stub targets. |
| auto &GOTEntrySymbol = getGOTEntry(Target); |
| StubContentBlock.addEdge(LDRLiteral19, 0, GOTEntrySymbol, 0); |
| return G.addAnonymousSymbol(StubContentBlock, 0, 8, true, false); |
| } |
| |
| void fixPLTEdge(Edge &E, Symbol &Stub) { |
| assert(E.getKind() == Branch26 && "Not a Branch32 edge?"); |
| assert(E.getAddend() == 0 && "Branch32 edge has non-zero addend?"); |
| E.setTarget(Stub); |
| } |
| |
| private: |
| Section &getGOTSection() { |
| if (!GOTSection) |
| GOTSection = &G.createSection("$__GOT", sys::Memory::MF_READ); |
| return *GOTSection; |
| } |
| |
| Section &getStubsSection() { |
| if (!StubsSection) { |
| auto StubsProt = static_cast<sys::Memory::ProtectionFlags>( |
| sys::Memory::MF_READ | sys::Memory::MF_EXEC); |
| StubsSection = &G.createSection("$__STUBS", StubsProt); |
| } |
| return *StubsSection; |
| } |
| |
| ArrayRef<char> getGOTEntryBlockContent() { |
| return {reinterpret_cast<const char *>(NullGOTEntryContent), |
| sizeof(NullGOTEntryContent)}; |
| } |
| |
| ArrayRef<char> getStubBlockContent() { |
| return {reinterpret_cast<const char *>(StubContent), sizeof(StubContent)}; |
| } |
| |
| static const uint8_t NullGOTEntryContent[8]; |
| static const uint8_t StubContent[8]; |
| Section *GOTSection = nullptr; |
| Section *StubsSection = nullptr; |
| }; |
| |
| const uint8_t |
| PerGraphGOTAndPLTStubsBuilder_MachO_arm64::NullGOTEntryContent[8] = { |
| 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}; |
| const uint8_t PerGraphGOTAndPLTStubsBuilder_MachO_arm64::StubContent[8] = { |
| 0x10, 0x00, 0x00, 0x58, // LDR x16, <literal> |
| 0x00, 0x02, 0x1f, 0xd6 // BR x16 |
| }; |
| |
| } // namespace |
| |
| namespace llvm { |
| namespace jitlink { |
| |
| class MachOJITLinker_arm64 : public JITLinker<MachOJITLinker_arm64> { |
| friend class JITLinker<MachOJITLinker_arm64>; |
| |
| public: |
| MachOJITLinker_arm64(std::unique_ptr<JITLinkContext> Ctx, |
| std::unique_ptr<LinkGraph> G, |
| PassConfiguration PassConfig) |
| : JITLinker(std::move(Ctx), std::move(G), std::move(PassConfig)) {} |
| |
| private: |
| |
| static unsigned getPageOffset12Shift(uint32_t Instr) { |
| constexpr uint32_t LoadStoreImm12Mask = 0x3b000000; |
| constexpr uint32_t Vec128Mask = 0x04800000; |
| |
| if ((Instr & LoadStoreImm12Mask) == 0x39000000) { |
| uint32_t ImplicitShift = Instr >> 30; |
| if (ImplicitShift == 0) |
| if ((Instr & Vec128Mask) == Vec128Mask) |
| ImplicitShift = 4; |
| |
| return ImplicitShift; |
| } |
| |
| return 0; |
| } |
| |
| Error applyFixup(LinkGraph &G, Block &B, const Edge &E, |
| char *BlockWorkingMem) const { |
| using namespace support; |
| |
| char *FixupPtr = BlockWorkingMem + E.getOffset(); |
| JITTargetAddress FixupAddress = B.getAddress() + E.getOffset(); |
| |
| switch (E.getKind()) { |
| case Branch26: { |
| assert((FixupAddress & 0x3) == 0 && "Branch-inst is not 32-bit aligned"); |
| |
| int64_t Value = E.getTarget().getAddress() - FixupAddress + E.getAddend(); |
| |
| if (static_cast<uint64_t>(Value) & 0x3) |
| return make_error<JITLinkError>("Branch26 target is not 32-bit " |
| "aligned"); |
| |
| if (Value < -(1 << 27) || Value > ((1 << 27) - 1)) |
| return makeTargetOutOfRangeError(G, B, E); |
| |
| uint32_t RawInstr = *(little32_t *)FixupPtr; |
| assert((RawInstr & 0x7fffffff) == 0x14000000 && |
| "RawInstr isn't a B or BR immediate instruction"); |
| uint32_t Imm = (static_cast<uint32_t>(Value) & ((1 << 28) - 1)) >> 2; |
| uint32_t FixedInstr = RawInstr | Imm; |
| *(little32_t *)FixupPtr = FixedInstr; |
| break; |
| } |
| case Pointer32: { |
| uint64_t Value = E.getTarget().getAddress() + E.getAddend(); |
| if (Value > std::numeric_limits<uint32_t>::max()) |
| return makeTargetOutOfRangeError(G, B, E); |
| *(ulittle32_t *)FixupPtr = Value; |
| break; |
| } |
| case Pointer64: |
| case Pointer64Anon: { |
| uint64_t Value = E.getTarget().getAddress() + E.getAddend(); |
| *(ulittle64_t *)FixupPtr = Value; |
| break; |
| } |
| case Page21: |
| case GOTPage21: { |
| assert((E.getKind() != GOTPage21 || E.getAddend() == 0) && |
| "GOTPAGE21 with non-zero addend"); |
| uint64_t TargetPage = |
| (E.getTarget().getAddress() + E.getAddend()) & |
| ~static_cast<uint64_t>(4096 - 1); |
| uint64_t PCPage = FixupAddress & ~static_cast<uint64_t>(4096 - 1); |
| |
| int64_t PageDelta = TargetPage - PCPage; |
| if (PageDelta < -(1 << 30) || PageDelta > ((1 << 30) - 1)) |
| return makeTargetOutOfRangeError(G, B, E); |
| |
| uint32_t RawInstr = *(ulittle32_t *)FixupPtr; |
| assert((RawInstr & 0xffffffe0) == 0x90000000 && |
| "RawInstr isn't an ADRP instruction"); |
| uint32_t ImmLo = (static_cast<uint64_t>(PageDelta) >> 12) & 0x3; |
| uint32_t ImmHi = (static_cast<uint64_t>(PageDelta) >> 14) & 0x7ffff; |
| uint32_t FixedInstr = RawInstr | (ImmLo << 29) | (ImmHi << 5); |
| *(ulittle32_t *)FixupPtr = FixedInstr; |
| break; |
| } |
| case PageOffset12: { |
| uint64_t TargetOffset = |
| (E.getTarget().getAddress() + E.getAddend()) & 0xfff; |
| |
| uint32_t RawInstr = *(ulittle32_t *)FixupPtr; |
| unsigned ImmShift = getPageOffset12Shift(RawInstr); |
| |
| if (TargetOffset & ((1 << ImmShift) - 1)) |
| return make_error<JITLinkError>("PAGEOFF12 target is not aligned"); |
| |
| uint32_t EncodedImm = (TargetOffset >> ImmShift) << 10; |
| uint32_t FixedInstr = RawInstr | EncodedImm; |
| *(ulittle32_t *)FixupPtr = FixedInstr; |
| break; |
| } |
| case GOTPageOffset12: { |
| assert(E.getAddend() == 0 && "GOTPAGEOF12 with non-zero addend"); |
| |
| uint32_t RawInstr = *(ulittle32_t *)FixupPtr; |
| assert((RawInstr & 0xfffffc00) == 0xf9400000 && |
| "RawInstr isn't a 64-bit LDR immediate"); |
| |
| uint32_t TargetOffset = E.getTarget().getAddress() & 0xfff; |
| assert((TargetOffset & 0x7) == 0 && "GOT entry is not 8-byte aligned"); |
| uint32_t EncodedImm = (TargetOffset >> 3) << 10; |
| uint32_t FixedInstr = RawInstr | EncodedImm; |
| *(ulittle32_t *)FixupPtr = FixedInstr; |
| break; |
| } |
| case LDRLiteral19: { |
| assert((FixupAddress & 0x3) == 0 && "LDR is not 32-bit aligned"); |
| assert(E.getAddend() == 0 && "LDRLiteral19 with non-zero addend"); |
| uint32_t RawInstr = *(ulittle32_t *)FixupPtr; |
| assert(RawInstr == 0x58000010 && "RawInstr isn't a 64-bit LDR literal"); |
| int64_t Delta = E.getTarget().getAddress() - FixupAddress; |
| if (Delta & 0x3) |
| return make_error<JITLinkError>("LDR literal target is not 32-bit " |
| "aligned"); |
| if (Delta < -(1 << 20) || Delta > ((1 << 20) - 1)) |
| return makeTargetOutOfRangeError(G, B, E); |
| |
| uint32_t EncodedImm = (static_cast<uint32_t>(Delta) >> 2) << 5; |
| uint32_t FixedInstr = RawInstr | EncodedImm; |
| *(ulittle32_t *)FixupPtr = FixedInstr; |
| break; |
| } |
| case Delta32: |
| case Delta64: |
| case NegDelta32: |
| case NegDelta64: { |
| int64_t Value; |
| if (E.getKind() == Delta32 || E.getKind() == Delta64) |
| Value = E.getTarget().getAddress() - FixupAddress + E.getAddend(); |
| else |
| Value = FixupAddress - E.getTarget().getAddress() + E.getAddend(); |
| |
| if (E.getKind() == Delta32 || E.getKind() == NegDelta32) { |
| if (Value < std::numeric_limits<int32_t>::min() || |
| Value > std::numeric_limits<int32_t>::max()) |
| return makeTargetOutOfRangeError(G, B, E); |
| *(little32_t *)FixupPtr = Value; |
| } else |
| *(little64_t *)FixupPtr = Value; |
| break; |
| } |
| default: |
| llvm_unreachable("Unrecognized edge kind"); |
| } |
| |
| return Error::success(); |
| } |
| |
| uint64_t NullValue = 0; |
| }; |
| |
| Expected<std::unique_ptr<LinkGraph>> |
| createLinkGraphFromMachOObject_arm64(MemoryBufferRef ObjectBuffer) { |
| auto MachOObj = object::ObjectFile::createMachOObjectFile(ObjectBuffer); |
| if (!MachOObj) |
| return MachOObj.takeError(); |
| return MachOLinkGraphBuilder_arm64(**MachOObj).buildGraph(); |
| } |
| |
| void link_MachO_arm64(std::unique_ptr<LinkGraph> G, |
| std::unique_ptr<JITLinkContext> Ctx) { |
| |
| PassConfiguration Config; |
| |
| if (Ctx->shouldAddDefaultTargetPasses(G->getTargetTriple())) { |
| // Add a mark-live pass. |
| if (auto MarkLive = Ctx->getMarkLivePass(G->getTargetTriple())) |
| Config.PrePrunePasses.push_back(std::move(MarkLive)); |
| else |
| Config.PrePrunePasses.push_back(markAllSymbolsLive); |
| |
| // Add an in-place GOT/Stubs pass. |
| Config.PostPrunePasses.push_back( |
| PerGraphGOTAndPLTStubsBuilder_MachO_arm64::asPass); |
| } |
| |
| if (auto Err = Ctx->modifyPassConfig(*G, Config)) |
| return Ctx->notifyFailed(std::move(Err)); |
| |
| // Construct a JITLinker and run the link function. |
| MachOJITLinker_arm64::link(std::move(Ctx), std::move(G), std::move(Config)); |
| } |
| |
| const char *getMachOARM64RelocationKindName(Edge::Kind R) { |
| switch (R) { |
| case Branch26: |
| return "Branch26"; |
| case Pointer64: |
| return "Pointer64"; |
| case Pointer64Anon: |
| return "Pointer64Anon"; |
| case Page21: |
| return "Page21"; |
| case PageOffset12: |
| return "PageOffset12"; |
| case GOTPage21: |
| return "GOTPage21"; |
| case GOTPageOffset12: |
| return "GOTPageOffset12"; |
| case PointerToGOT: |
| return "PointerToGOT"; |
| case PairedAddend: |
| return "PairedAddend"; |
| case LDRLiteral19: |
| return "LDRLiteral19"; |
| case Delta32: |
| return "Delta32"; |
| case Delta64: |
| return "Delta64"; |
| case NegDelta32: |
| return "NegDelta32"; |
| case NegDelta64: |
| return "NegDelta64"; |
| default: |
| return getGenericEdgeKindName(static_cast<Edge::Kind>(R)); |
| } |
| } |
| |
| } // end namespace jitlink |
| } // end namespace llvm |
