diff options
Diffstat (limited to 'contrib/llvm/lib/Bitcode/Reader/MetadataLoader.cpp')
-rw-r--r-- | contrib/llvm/lib/Bitcode/Reader/MetadataLoader.cpp | 1850 |
1 files changed, 1850 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Bitcode/Reader/MetadataLoader.cpp b/contrib/llvm/lib/Bitcode/Reader/MetadataLoader.cpp new file mode 100644 index 0000000..b89f5be --- /dev/null +++ b/contrib/llvm/lib/Bitcode/Reader/MetadataLoader.cpp @@ -0,0 +1,1850 @@ +//===- MetadataLoader.cpp - Internal BitcodeReader implementation ---------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "MetadataLoader.h" +#include "ValueList.h" + +#include "llvm/ADT/APFloat.h" +#include "llvm/ADT/APInt.h" +#include "llvm/ADT/ArrayRef.h" +#include "llvm/ADT/DenseMap.h" +#include "llvm/ADT/DenseSet.h" +#include "llvm/ADT/None.h" +#include "llvm/ADT/STLExtras.h" +#include "llvm/ADT/SmallString.h" +#include "llvm/ADT/SmallVector.h" +#include "llvm/ADT/Statistic.h" +#include "llvm/ADT/StringRef.h" +#include "llvm/ADT/Triple.h" +#include "llvm/ADT/Twine.h" +#include "llvm/Bitcode/BitcodeReader.h" +#include "llvm/Bitcode/BitstreamReader.h" +#include "llvm/Bitcode/LLVMBitCodes.h" +#include "llvm/IR/Argument.h" +#include "llvm/IR/Attributes.h" +#include "llvm/IR/AutoUpgrade.h" +#include "llvm/IR/BasicBlock.h" +#include "llvm/IR/CallSite.h" +#include "llvm/IR/CallingConv.h" +#include "llvm/IR/Comdat.h" +#include "llvm/IR/Constant.h" +#include "llvm/IR/Constants.h" +#include "llvm/IR/DebugInfo.h" +#include "llvm/IR/DebugInfoMetadata.h" +#include "llvm/IR/DebugLoc.h" +#include "llvm/IR/DerivedTypes.h" +#include "llvm/IR/DiagnosticInfo.h" +#include "llvm/IR/DiagnosticPrinter.h" +#include "llvm/IR/Function.h" +#include "llvm/IR/GVMaterializer.h" +#include "llvm/IR/GlobalAlias.h" +#include "llvm/IR/GlobalIFunc.h" +#include "llvm/IR/GlobalIndirectSymbol.h" +#include "llvm/IR/GlobalObject.h" +#include "llvm/IR/GlobalValue.h" +#include "llvm/IR/GlobalVariable.h" +#include "llvm/IR/InlineAsm.h" +#include "llvm/IR/InstrTypes.h" +#include "llvm/IR/Instruction.h" +#include "llvm/IR/Instructions.h" +#include "llvm/IR/Intrinsics.h" +#include "llvm/IR/LLVMContext.h" +#include "llvm/IR/Module.h" +#include "llvm/IR/ModuleSummaryIndex.h" +#include "llvm/IR/OperandTraits.h" +#include "llvm/IR/Operator.h" +#include "llvm/IR/TrackingMDRef.h" +#include "llvm/IR/Type.h" +#include "llvm/IR/ValueHandle.h" +#include "llvm/Support/AtomicOrdering.h" +#include "llvm/Support/Casting.h" +#include "llvm/Support/CommandLine.h" +#include "llvm/Support/Compiler.h" +#include "llvm/Support/Debug.h" +#include "llvm/Support/Error.h" +#include "llvm/Support/ErrorHandling.h" +#include "llvm/Support/ManagedStatic.h" +#include "llvm/Support/MemoryBuffer.h" +#include "llvm/Support/raw_ostream.h" +#include <algorithm> +#include <cassert> +#include <cstddef> +#include <cstdint> +#include <deque> +#include <limits> +#include <map> +#include <memory> +#include <string> +#include <system_error> +#include <tuple> +#include <utility> +#include <vector> + +using namespace llvm; + +#define DEBUG_TYPE "bitcode-reader" + +STATISTIC(NumMDStringLoaded, "Number of MDStrings loaded"); +STATISTIC(NumMDNodeTemporary, "Number of MDNode::Temporary created"); +STATISTIC(NumMDRecordLoaded, "Number of Metadata records loaded"); + +/// Flag whether we need to import full type definitions for ThinLTO. +/// Currently needed for Darwin and LLDB. +static cl::opt<bool> ImportFullTypeDefinitions( + "import-full-type-definitions", cl::init(false), cl::Hidden, + cl::desc("Import full type definitions for ThinLTO.")); + +static cl::opt<bool> DisableLazyLoading( + "disable-ondemand-mds-loading", cl::init(false), cl::Hidden, + cl::desc("Force disable the lazy-loading on-demand of metadata when " + "loading bitcode for importing.")); + +namespace { + +static int64_t unrotateSign(uint64_t U) { return U & 1 ? ~(U >> 1) : U >> 1; } + +class BitcodeReaderMetadataList { + /// Array of metadata references. + /// + /// Don't use std::vector here. Some versions of libc++ copy (instead of + /// move) on resize, and TrackingMDRef is very expensive to copy. + SmallVector<TrackingMDRef, 1> MetadataPtrs; + + /// The set of indices in MetadataPtrs above of forward references that were + /// generated. + SmallDenseSet<unsigned, 1> ForwardReference; + + /// The set of indices in MetadataPtrs above of Metadata that need to be + /// resolved. + SmallDenseSet<unsigned, 1> UnresolvedNodes; + + /// Structures for resolving old type refs. + struct { + SmallDenseMap<MDString *, TempMDTuple, 1> Unknown; + SmallDenseMap<MDString *, DICompositeType *, 1> Final; + SmallDenseMap<MDString *, DICompositeType *, 1> FwdDecls; + SmallVector<std::pair<TrackingMDRef, TempMDTuple>, 1> Arrays; + } OldTypeRefs; + + LLVMContext &Context; + +public: + BitcodeReaderMetadataList(LLVMContext &C) : Context(C) {} + + // vector compatibility methods + unsigned size() const { return MetadataPtrs.size(); } + void resize(unsigned N) { MetadataPtrs.resize(N); } + void push_back(Metadata *MD) { MetadataPtrs.emplace_back(MD); } + void clear() { MetadataPtrs.clear(); } + Metadata *back() const { return MetadataPtrs.back(); } + void pop_back() { MetadataPtrs.pop_back(); } + bool empty() const { return MetadataPtrs.empty(); } + + Metadata *operator[](unsigned i) const { + assert(i < MetadataPtrs.size()); + return MetadataPtrs[i]; + } + + Metadata *lookup(unsigned I) const { + if (I < MetadataPtrs.size()) + return MetadataPtrs[I]; + return nullptr; + } + + void shrinkTo(unsigned N) { + assert(N <= size() && "Invalid shrinkTo request!"); + assert(ForwardReference.empty() && "Unexpected forward refs"); + assert(UnresolvedNodes.empty() && "Unexpected unresolved node"); + MetadataPtrs.resize(N); + } + + /// Return the given metadata, creating a replaceable forward reference if + /// necessary. + Metadata *getMetadataFwdRef(unsigned Idx); + + /// Return the the given metadata only if it is fully resolved. + /// + /// Gives the same result as \a lookup(), unless \a MDNode::isResolved() + /// would give \c false. + Metadata *getMetadataIfResolved(unsigned Idx); + + MDNode *getMDNodeFwdRefOrNull(unsigned Idx); + void assignValue(Metadata *MD, unsigned Idx); + void tryToResolveCycles(); + bool hasFwdRefs() const { return !ForwardReference.empty(); } + int getNextFwdRef() { + assert(hasFwdRefs()); + return *ForwardReference.begin(); + } + + /// Upgrade a type that had an MDString reference. + void addTypeRef(MDString &UUID, DICompositeType &CT); + + /// Upgrade a type that had an MDString reference. + Metadata *upgradeTypeRef(Metadata *MaybeUUID); + + /// Upgrade a type ref array that may have MDString references. + Metadata *upgradeTypeRefArray(Metadata *MaybeTuple); + +private: + Metadata *resolveTypeRefArray(Metadata *MaybeTuple); +}; + +void BitcodeReaderMetadataList::assignValue(Metadata *MD, unsigned Idx) { + if (auto *MDN = dyn_cast<MDNode>(MD)) + if (!MDN->isResolved()) + UnresolvedNodes.insert(Idx); + + if (Idx == size()) { + push_back(MD); + return; + } + + if (Idx >= size()) + resize(Idx + 1); + + TrackingMDRef &OldMD = MetadataPtrs[Idx]; + if (!OldMD) { + OldMD.reset(MD); + return; + } + + // If there was a forward reference to this value, replace it. + TempMDTuple PrevMD(cast<MDTuple>(OldMD.get())); + PrevMD->replaceAllUsesWith(MD); + ForwardReference.erase(Idx); +} + +Metadata *BitcodeReaderMetadataList::getMetadataFwdRef(unsigned Idx) { + if (Idx >= size()) + resize(Idx + 1); + + if (Metadata *MD = MetadataPtrs[Idx]) + return MD; + + // Track forward refs to be resolved later. + ForwardReference.insert(Idx); + + // Create and return a placeholder, which will later be RAUW'd. + ++NumMDNodeTemporary; + Metadata *MD = MDNode::getTemporary(Context, None).release(); + MetadataPtrs[Idx].reset(MD); + return MD; +} + +Metadata *BitcodeReaderMetadataList::getMetadataIfResolved(unsigned Idx) { + Metadata *MD = lookup(Idx); + if (auto *N = dyn_cast_or_null<MDNode>(MD)) + if (!N->isResolved()) + return nullptr; + return MD; +} + +MDNode *BitcodeReaderMetadataList::getMDNodeFwdRefOrNull(unsigned Idx) { + return dyn_cast_or_null<MDNode>(getMetadataFwdRef(Idx)); +} + +void BitcodeReaderMetadataList::tryToResolveCycles() { + if (!ForwardReference.empty()) + // Still forward references... can't resolve cycles. + return; + + // Give up on finding a full definition for any forward decls that remain. + for (const auto &Ref : OldTypeRefs.FwdDecls) + OldTypeRefs.Final.insert(Ref); + OldTypeRefs.FwdDecls.clear(); + + // Upgrade from old type ref arrays. In strange cases, this could add to + // OldTypeRefs.Unknown. + for (const auto &Array : OldTypeRefs.Arrays) + Array.second->replaceAllUsesWith(resolveTypeRefArray(Array.first.get())); + OldTypeRefs.Arrays.clear(); + + // Replace old string-based type refs with the resolved node, if possible. + // If we haven't seen the node, leave it to the verifier to complain about + // the invalid string reference. + for (const auto &Ref : OldTypeRefs.Unknown) { + if (DICompositeType *CT = OldTypeRefs.Final.lookup(Ref.first)) + Ref.second->replaceAllUsesWith(CT); + else + Ref.second->replaceAllUsesWith(Ref.first); + } + OldTypeRefs.Unknown.clear(); + + if (UnresolvedNodes.empty()) + // Nothing to do. + return; + + // Resolve any cycles. + for (unsigned I : UnresolvedNodes) { + auto &MD = MetadataPtrs[I]; + auto *N = dyn_cast_or_null<MDNode>(MD); + if (!N) + continue; + + assert(!N->isTemporary() && "Unexpected forward reference"); + N->resolveCycles(); + } + + // Make sure we return early again until there's another unresolved ref. + UnresolvedNodes.clear(); +} + +void BitcodeReaderMetadataList::addTypeRef(MDString &UUID, + DICompositeType &CT) { + assert(CT.getRawIdentifier() == &UUID && "Mismatched UUID"); + if (CT.isForwardDecl()) + OldTypeRefs.FwdDecls.insert(std::make_pair(&UUID, &CT)); + else + OldTypeRefs.Final.insert(std::make_pair(&UUID, &CT)); +} + +Metadata *BitcodeReaderMetadataList::upgradeTypeRef(Metadata *MaybeUUID) { + auto *UUID = dyn_cast_or_null<MDString>(MaybeUUID); + if (LLVM_LIKELY(!UUID)) + return MaybeUUID; + + if (auto *CT = OldTypeRefs.Final.lookup(UUID)) + return CT; + + auto &Ref = OldTypeRefs.Unknown[UUID]; + if (!Ref) + Ref = MDNode::getTemporary(Context, None); + return Ref.get(); +} + +Metadata *BitcodeReaderMetadataList::upgradeTypeRefArray(Metadata *MaybeTuple) { + auto *Tuple = dyn_cast_or_null<MDTuple>(MaybeTuple); + if (!Tuple || Tuple->isDistinct()) + return MaybeTuple; + + // Look through the array immediately if possible. + if (!Tuple->isTemporary()) + return resolveTypeRefArray(Tuple); + + // Create and return a placeholder to use for now. Eventually + // resolveTypeRefArrays() will be resolve this forward reference. + OldTypeRefs.Arrays.emplace_back( + std::piecewise_construct, std::forward_as_tuple(Tuple), + std::forward_as_tuple(MDTuple::getTemporary(Context, None))); + return OldTypeRefs.Arrays.back().second.get(); +} + +Metadata *BitcodeReaderMetadataList::resolveTypeRefArray(Metadata *MaybeTuple) { + auto *Tuple = dyn_cast_or_null<MDTuple>(MaybeTuple); + if (!Tuple || Tuple->isDistinct()) + return MaybeTuple; + + // Look through the DITypeRefArray, upgrading each DITypeRef. + SmallVector<Metadata *, 32> Ops; + Ops.reserve(Tuple->getNumOperands()); + for (Metadata *MD : Tuple->operands()) + Ops.push_back(upgradeTypeRef(MD)); + + return MDTuple::get(Context, Ops); +} + +namespace { + +class PlaceholderQueue { + // Placeholders would thrash around when moved, so store in a std::deque + // instead of some sort of vector. + std::deque<DistinctMDOperandPlaceholder> PHs; + +public: + bool empty() { return PHs.empty(); } + DistinctMDOperandPlaceholder &getPlaceholderOp(unsigned ID); + void flush(BitcodeReaderMetadataList &MetadataList); + + /// Return the list of temporaries nodes in the queue, these need to be + /// loaded before we can flush the queue. + void getTemporaries(BitcodeReaderMetadataList &MetadataList, + DenseSet<unsigned> &Temporaries) { + for (auto &PH : PHs) { + auto ID = PH.getID(); + auto *MD = MetadataList.lookup(ID); + if (!MD) { + Temporaries.insert(ID); + continue; + } + auto *N = dyn_cast_or_null<MDNode>(MD); + if (N && N->isTemporary()) + Temporaries.insert(ID); + } + } +}; + +} // end anonymous namespace + +DistinctMDOperandPlaceholder &PlaceholderQueue::getPlaceholderOp(unsigned ID) { + PHs.emplace_back(ID); + return PHs.back(); +} + +void PlaceholderQueue::flush(BitcodeReaderMetadataList &MetadataList) { + while (!PHs.empty()) { + auto *MD = MetadataList.lookup(PHs.front().getID()); + assert(MD && "Flushing placeholder on unassigned MD"); +#ifndef NDEBUG + if (auto *MDN = dyn_cast<MDNode>(MD)) + assert(MDN->isResolved() && + "Flushing Placeholder while cycles aren't resolved"); +#endif + PHs.front().replaceUseWith(MD); + PHs.pop_front(); + } +} + +} // anonynous namespace + +class MetadataLoader::MetadataLoaderImpl { + BitcodeReaderMetadataList MetadataList; + BitcodeReaderValueList &ValueList; + BitstreamCursor &Stream; + LLVMContext &Context; + Module &TheModule; + std::function<Type *(unsigned)> getTypeByID; + + /// Cursor associated with the lazy-loading of Metadata. This is the easy way + /// to keep around the right "context" (Abbrev list) to be able to jump in + /// the middle of the metadata block and load any record. + BitstreamCursor IndexCursor; + + /// Index that keeps track of MDString values. + std::vector<StringRef> MDStringRef; + + /// On-demand loading of a single MDString. Requires the index above to be + /// populated. + MDString *lazyLoadOneMDString(unsigned Idx); + + /// Index that keeps track of where to find a metadata record in the stream. + std::vector<uint64_t> GlobalMetadataBitPosIndex; + + /// Populate the index above to enable lazily loading of metadata, and load + /// the named metadata as well as the transitively referenced global + /// Metadata. + Expected<bool> lazyLoadModuleMetadataBlock(); + + /// On-demand loading of a single metadata. Requires the index above to be + /// populated. + void lazyLoadOneMetadata(unsigned Idx, PlaceholderQueue &Placeholders); + + // Keep mapping of seens pair of old-style CU <-> SP, and update pointers to + // point from SP to CU after a block is completly parsed. + std::vector<std::pair<DICompileUnit *, Metadata *>> CUSubprograms; + + /// Functions that need to be matched with subprograms when upgrading old + /// metadata. + SmallDenseMap<Function *, DISubprogram *, 16> FunctionsWithSPs; + + // Map the bitcode's custom MDKind ID to the Module's MDKind ID. + DenseMap<unsigned, unsigned> MDKindMap; + + bool StripTBAA = false; + bool HasSeenOldLoopTags = false; + bool NeedUpgradeToDIGlobalVariableExpression = false; + + /// True if metadata is being parsed for a module being ThinLTO imported. + bool IsImporting = false; + + Error parseOneMetadata(SmallVectorImpl<uint64_t> &Record, unsigned Code, + PlaceholderQueue &Placeholders, StringRef Blob, + unsigned &NextMetadataNo); + Error parseMetadataStrings(ArrayRef<uint64_t> Record, StringRef Blob, + std::function<void(StringRef)> CallBack); + Error parseGlobalObjectAttachment(GlobalObject &GO, + ArrayRef<uint64_t> Record); + Error parseMetadataKindRecord(SmallVectorImpl<uint64_t> &Record); + + void resolveForwardRefsAndPlaceholders(PlaceholderQueue &Placeholders); + + /// Upgrade old-style CU <-> SP pointers to point from SP to CU. + void upgradeCUSubprograms() { + for (auto CU_SP : CUSubprograms) + if (auto *SPs = dyn_cast_or_null<MDTuple>(CU_SP.second)) + for (auto &Op : SPs->operands()) + if (auto *SP = dyn_cast_or_null<MDNode>(Op)) + SP->replaceOperandWith(7, CU_SP.first); + CUSubprograms.clear(); + } + + /// Upgrade old-style bare DIGlobalVariables to DIGlobalVariableExpressions. + void upgradeCUVariables() { + if (!NeedUpgradeToDIGlobalVariableExpression) + return; + + // Upgrade list of variables attached to the CUs. + if (NamedMDNode *CUNodes = TheModule.getNamedMetadata("llvm.dbg.cu")) + for (unsigned I = 0, E = CUNodes->getNumOperands(); I != E; ++I) { + auto *CU = cast<DICompileUnit>(CUNodes->getOperand(I)); + if (auto *GVs = dyn_cast_or_null<MDTuple>(CU->getRawGlobalVariables())) + for (unsigned I = 0; I < GVs->getNumOperands(); I++) + if (auto *GV = + dyn_cast_or_null<DIGlobalVariable>(GVs->getOperand(I))) { + auto *DGVE = + DIGlobalVariableExpression::getDistinct(Context, GV, nullptr); + GVs->replaceOperandWith(I, DGVE); + } + } + + // Upgrade variables attached to globals. + for (auto &GV : TheModule.globals()) { + SmallVector<MDNode *, 1> MDs, NewMDs; + GV.getMetadata(LLVMContext::MD_dbg, MDs); + GV.eraseMetadata(LLVMContext::MD_dbg); + for (auto *MD : MDs) + if (auto *DGV = dyn_cast_or_null<DIGlobalVariable>(MD)) { + auto *DGVE = + DIGlobalVariableExpression::getDistinct(Context, DGV, nullptr); + GV.addMetadata(LLVMContext::MD_dbg, *DGVE); + } else + GV.addMetadata(LLVMContext::MD_dbg, *MD); + } + } + + void upgradeDebugInfo() { + upgradeCUSubprograms(); + upgradeCUVariables(); + } + +public: + MetadataLoaderImpl(BitstreamCursor &Stream, Module &TheModule, + BitcodeReaderValueList &ValueList, + std::function<Type *(unsigned)> getTypeByID, + bool IsImporting) + : MetadataList(TheModule.getContext()), ValueList(ValueList), + Stream(Stream), Context(TheModule.getContext()), TheModule(TheModule), + getTypeByID(getTypeByID), IsImporting(IsImporting) {} + + Error parseMetadata(bool ModuleLevel); + + bool hasFwdRefs() const { return MetadataList.hasFwdRefs(); } + + Metadata *getMetadataFwdRefOrLoad(unsigned ID) { + if (ID < MDStringRef.size()) + return lazyLoadOneMDString(ID); + if (auto *MD = MetadataList.lookup(ID)) + return MD; + // If lazy-loading is enabled, we try recursively to load the operand + // instead of creating a temporary. + if (ID < (MDStringRef.size() + GlobalMetadataBitPosIndex.size())) { + PlaceholderQueue Placeholders; + lazyLoadOneMetadata(ID, Placeholders); + resolveForwardRefsAndPlaceholders(Placeholders); + return MetadataList.lookup(ID); + } + return MetadataList.getMetadataFwdRef(ID); + } + + MDNode *getMDNodeFwdRefOrNull(unsigned Idx) { + return MetadataList.getMDNodeFwdRefOrNull(Idx); + } + + DISubprogram *lookupSubprogramForFunction(Function *F) { + return FunctionsWithSPs.lookup(F); + } + + bool hasSeenOldLoopTags() { return HasSeenOldLoopTags; } + + Error parseMetadataAttachment( + Function &F, const SmallVectorImpl<Instruction *> &InstructionList); + + Error parseMetadataKinds(); + + void setStripTBAA(bool Value) { StripTBAA = Value; } + bool isStrippingTBAA() { return StripTBAA; } + + unsigned size() const { return MetadataList.size(); } + void shrinkTo(unsigned N) { MetadataList.shrinkTo(N); } +}; + +Error error(const Twine &Message) { + return make_error<StringError>( + Message, make_error_code(BitcodeError::CorruptedBitcode)); +} + +Expected<bool> +MetadataLoader::MetadataLoaderImpl::lazyLoadModuleMetadataBlock() { + IndexCursor = Stream; + SmallVector<uint64_t, 64> Record; + // Get the abbrevs, and preload record positions to make them lazy-loadable. + while (true) { + BitstreamEntry Entry = IndexCursor.advanceSkippingSubblocks( + BitstreamCursor::AF_DontPopBlockAtEnd); + switch (Entry.Kind) { + case BitstreamEntry::SubBlock: // Handled for us already. + case BitstreamEntry::Error: + return error("Malformed block"); + case BitstreamEntry::EndBlock: { + return true; + } + case BitstreamEntry::Record: { + // The interesting case. + ++NumMDRecordLoaded; + uint64_t CurrentPos = IndexCursor.GetCurrentBitNo(); + auto Code = IndexCursor.skipRecord(Entry.ID); + switch (Code) { + case bitc::METADATA_STRINGS: { + // Rewind and parse the strings. + IndexCursor.JumpToBit(CurrentPos); + StringRef Blob; + Record.clear(); + IndexCursor.readRecord(Entry.ID, Record, &Blob); + unsigned NumStrings = Record[0]; + MDStringRef.reserve(NumStrings); + auto IndexNextMDString = [&](StringRef Str) { + MDStringRef.push_back(Str); + }; + if (auto Err = parseMetadataStrings(Record, Blob, IndexNextMDString)) + return std::move(Err); + break; + } + case bitc::METADATA_INDEX_OFFSET: { + // This is the offset to the index, when we see this we skip all the + // records and load only an index to these. + IndexCursor.JumpToBit(CurrentPos); + Record.clear(); + IndexCursor.readRecord(Entry.ID, Record); + if (Record.size() != 2) + return error("Invalid record"); + auto Offset = Record[0] + (Record[1] << 32); + auto BeginPos = IndexCursor.GetCurrentBitNo(); + IndexCursor.JumpToBit(BeginPos + Offset); + Entry = IndexCursor.advanceSkippingSubblocks( + BitstreamCursor::AF_DontPopBlockAtEnd); + assert(Entry.Kind == BitstreamEntry::Record && + "Corrupted bitcode: Expected `Record` when trying to find the " + "Metadata index"); + Record.clear(); + auto Code = IndexCursor.readRecord(Entry.ID, Record); + (void)Code; + assert(Code == bitc::METADATA_INDEX && "Corrupted bitcode: Expected " + "`METADATA_INDEX` when trying " + "to find the Metadata index"); + + // Delta unpack + auto CurrentValue = BeginPos; + GlobalMetadataBitPosIndex.reserve(Record.size()); + for (auto &Elt : Record) { + CurrentValue += Elt; + GlobalMetadataBitPosIndex.push_back(CurrentValue); + } + break; + } + case bitc::METADATA_INDEX: + // We don't expect to get there, the Index is loaded when we encounter + // the offset. + return error("Corrupted Metadata block"); + case bitc::METADATA_NAME: { + // Named metadata need to be materialized now and aren't deferred. + IndexCursor.JumpToBit(CurrentPos); + Record.clear(); + unsigned Code = IndexCursor.readRecord(Entry.ID, Record); + assert(Code == bitc::METADATA_NAME); + + // Read name of the named metadata. + SmallString<8> Name(Record.begin(), Record.end()); + Code = IndexCursor.ReadCode(); + + // Named Metadata comes in two parts, we expect the name to be followed + // by the node + Record.clear(); + unsigned NextBitCode = IndexCursor.readRecord(Code, Record); + assert(NextBitCode == bitc::METADATA_NAMED_NODE); + (void)NextBitCode; + + // Read named metadata elements. + unsigned Size = Record.size(); + NamedMDNode *NMD = TheModule.getOrInsertNamedMetadata(Name); + for (unsigned i = 0; i != Size; ++i) { + // FIXME: We could use a placeholder here, however NamedMDNode are + // taking MDNode as operand and not using the Metadata infrastructure. + // It is acknowledged by 'TODO: Inherit from Metadata' in the + // NamedMDNode class definition. + MDNode *MD = MetadataList.getMDNodeFwdRefOrNull(Record[i]); + assert(MD && "Invalid record"); + NMD->addOperand(MD); + } + break; + } + case bitc::METADATA_GLOBAL_DECL_ATTACHMENT: { + // FIXME: we need to do this early because we don't materialize global + // value explicitly. + IndexCursor.JumpToBit(CurrentPos); + Record.clear(); + IndexCursor.readRecord(Entry.ID, Record); + if (Record.size() % 2 == 0) + return error("Invalid record"); + unsigned ValueID = Record[0]; + if (ValueID >= ValueList.size()) + return error("Invalid record"); + if (auto *GO = dyn_cast<GlobalObject>(ValueList[ValueID])) + if (Error Err = parseGlobalObjectAttachment( + *GO, ArrayRef<uint64_t>(Record).slice(1))) + return std::move(Err); + break; + } + case bitc::METADATA_KIND: + case bitc::METADATA_STRING_OLD: + case bitc::METADATA_OLD_FN_NODE: + case bitc::METADATA_OLD_NODE: + case bitc::METADATA_VALUE: + case bitc::METADATA_DISTINCT_NODE: + case bitc::METADATA_NODE: + case bitc::METADATA_LOCATION: + case bitc::METADATA_GENERIC_DEBUG: + case bitc::METADATA_SUBRANGE: + case bitc::METADATA_ENUMERATOR: + case bitc::METADATA_BASIC_TYPE: + case bitc::METADATA_DERIVED_TYPE: + case bitc::METADATA_COMPOSITE_TYPE: + case bitc::METADATA_SUBROUTINE_TYPE: + case bitc::METADATA_MODULE: + case bitc::METADATA_FILE: + case bitc::METADATA_COMPILE_UNIT: + case bitc::METADATA_SUBPROGRAM: + case bitc::METADATA_LEXICAL_BLOCK: + case bitc::METADATA_LEXICAL_BLOCK_FILE: + case bitc::METADATA_NAMESPACE: + case bitc::METADATA_MACRO: + case bitc::METADATA_MACRO_FILE: + case bitc::METADATA_TEMPLATE_TYPE: + case bitc::METADATA_TEMPLATE_VALUE: + case bitc::METADATA_GLOBAL_VAR: + case bitc::METADATA_LOCAL_VAR: + case bitc::METADATA_EXPRESSION: + case bitc::METADATA_OBJC_PROPERTY: + case bitc::METADATA_IMPORTED_ENTITY: + case bitc::METADATA_GLOBAL_VAR_EXPR: + // We don't expect to see any of these, if we see one, give up on + // lazy-loading and fallback. + MDStringRef.clear(); + GlobalMetadataBitPosIndex.clear(); + return false; + } + break; + } + } + } +} + +/// Parse a METADATA_BLOCK. If ModuleLevel is true then we are parsing +/// module level metadata. +Error MetadataLoader::MetadataLoaderImpl::parseMetadata(bool ModuleLevel) { + if (!ModuleLevel && MetadataList.hasFwdRefs()) + return error("Invalid metadata: fwd refs into function blocks"); + + // Record the entry position so that we can jump back here and efficiently + // skip the whole block in case we lazy-load. + auto EntryPos = Stream.GetCurrentBitNo(); + + if (Stream.EnterSubBlock(bitc::METADATA_BLOCK_ID)) + return error("Invalid record"); + + SmallVector<uint64_t, 64> Record; + PlaceholderQueue Placeholders; + + // We lazy-load module-level metadata: we build an index for each record, and + // then load individual record as needed, starting with the named metadata. + if (ModuleLevel && IsImporting && MetadataList.empty() && + !DisableLazyLoading) { + auto SuccessOrErr = lazyLoadModuleMetadataBlock(); + if (!SuccessOrErr) + return SuccessOrErr.takeError(); + if (SuccessOrErr.get()) { + // An index was successfully created and we will be able to load metadata + // on-demand. + MetadataList.resize(MDStringRef.size() + + GlobalMetadataBitPosIndex.size()); + + // Reading the named metadata created forward references and/or + // placeholders, that we flush here. + resolveForwardRefsAndPlaceholders(Placeholders); + upgradeDebugInfo(); + // Return at the beginning of the block, since it is easy to skip it + // entirely from there. + Stream.ReadBlockEnd(); // Pop the abbrev block context. + Stream.JumpToBit(EntryPos); + if (Stream.SkipBlock()) + return error("Invalid record"); + return Error::success(); + } + // Couldn't load an index, fallback to loading all the block "old-style". + } + + unsigned NextMetadataNo = MetadataList.size(); + + // Read all the records. + while (true) { + BitstreamEntry Entry = Stream.advanceSkippingSubblocks(); + + switch (Entry.Kind) { + case BitstreamEntry::SubBlock: // Handled for us already. + case BitstreamEntry::Error: + return error("Malformed block"); + case BitstreamEntry::EndBlock: + resolveForwardRefsAndPlaceholders(Placeholders); + upgradeDebugInfo(); + return Error::success(); + case BitstreamEntry::Record: + // The interesting case. + break; + } + + // Read a record. + Record.clear(); + StringRef Blob; + ++NumMDRecordLoaded; + unsigned Code = Stream.readRecord(Entry.ID, Record, &Blob); + if (Error Err = + parseOneMetadata(Record, Code, Placeholders, Blob, NextMetadataNo)) + return Err; + } +} + +MDString *MetadataLoader::MetadataLoaderImpl::lazyLoadOneMDString(unsigned ID) { + ++NumMDStringLoaded; + if (Metadata *MD = MetadataList.lookup(ID)) + return cast<MDString>(MD); + auto MDS = MDString::get(Context, MDStringRef[ID]); + MetadataList.assignValue(MDS, ID); + return MDS; +} + +void MetadataLoader::MetadataLoaderImpl::lazyLoadOneMetadata( + unsigned ID, PlaceholderQueue &Placeholders) { + assert(ID < (MDStringRef.size()) + GlobalMetadataBitPosIndex.size()); + assert(ID >= MDStringRef.size() && "Unexpected lazy-loading of MDString"); + // Lookup first if the metadata hasn't already been loaded. + if (auto *MD = MetadataList.lookup(ID)) { + auto *N = dyn_cast_or_null<MDNode>(MD); + if (!N->isTemporary()) + return; + } + SmallVector<uint64_t, 64> Record; + StringRef Blob; + IndexCursor.JumpToBit(GlobalMetadataBitPosIndex[ID - MDStringRef.size()]); + auto Entry = IndexCursor.advanceSkippingSubblocks(); + ++NumMDRecordLoaded; + unsigned Code = IndexCursor.readRecord(Entry.ID, Record, &Blob); + if (Error Err = parseOneMetadata(Record, Code, Placeholders, Blob, ID)) + report_fatal_error("Can't lazyload MD"); +} + +/// Ensure that all forward-references and placeholders are resolved. +/// Iteratively lazy-loading metadata on-demand if needed. +void MetadataLoader::MetadataLoaderImpl::resolveForwardRefsAndPlaceholders( + PlaceholderQueue &Placeholders) { + DenseSet<unsigned> Temporaries; + while (1) { + // Populate Temporaries with the placeholders that haven't been loaded yet. + Placeholders.getTemporaries(MetadataList, Temporaries); + + // If we don't have any temporary, or FwdReference, we're done! + if (Temporaries.empty() && !MetadataList.hasFwdRefs()) + break; + + // First, load all the temporaries. This can add new placeholders or + // forward references. + for (auto ID : Temporaries) + lazyLoadOneMetadata(ID, Placeholders); + Temporaries.clear(); + + // Second, load the forward-references. This can also add new placeholders + // or forward references. + while (MetadataList.hasFwdRefs()) + lazyLoadOneMetadata(MetadataList.getNextFwdRef(), Placeholders); + } + // At this point we don't have any forward reference remaining, or temporary + // that haven't been loaded. We can safely drop RAUW support and mark cycles + // as resolved. + MetadataList.tryToResolveCycles(); + + // Finally, everything is in place, we can replace the placeholders operands + // with the final node they refer to. + Placeholders.flush(MetadataList); +} + +Error MetadataLoader::MetadataLoaderImpl::parseOneMetadata( + SmallVectorImpl<uint64_t> &Record, unsigned Code, + PlaceholderQueue &Placeholders, StringRef Blob, unsigned &NextMetadataNo) { + + bool IsDistinct = false; + auto getMD = [&](unsigned ID) -> Metadata * { + if (ID < MDStringRef.size()) + return lazyLoadOneMDString(ID); + if (!IsDistinct) { + if (auto *MD = MetadataList.lookup(ID)) + return MD; + // If lazy-loading is enabled, we try recursively to load the operand + // instead of creating a temporary. + if (ID < (MDStringRef.size() + GlobalMetadataBitPosIndex.size())) { + // Create a temporary for the node that is referencing the operand we + // will lazy-load. It is needed before recursing in case there are + // uniquing cycles. + MetadataList.getMetadataFwdRef(NextMetadataNo); + lazyLoadOneMetadata(ID, Placeholders); + return MetadataList.lookup(ID); + } + // Return a temporary. + return MetadataList.getMetadataFwdRef(ID); + } + if (auto *MD = MetadataList.getMetadataIfResolved(ID)) + return MD; + return &Placeholders.getPlaceholderOp(ID); + }; + auto getMDOrNull = [&](unsigned ID) -> Metadata * { + if (ID) + return getMD(ID - 1); + return nullptr; + }; + auto getMDOrNullWithoutPlaceholders = [&](unsigned ID) -> Metadata * { + if (ID) + return MetadataList.getMetadataFwdRef(ID - 1); + return nullptr; + }; + auto getMDString = [&](unsigned ID) -> MDString * { + // This requires that the ID is not really a forward reference. In + // particular, the MDString must already have been resolved. + auto MDS = getMDOrNull(ID); + return cast_or_null<MDString>(MDS); + }; + + // Support for old type refs. + auto getDITypeRefOrNull = [&](unsigned ID) { + return MetadataList.upgradeTypeRef(getMDOrNull(ID)); + }; + +#define GET_OR_DISTINCT(CLASS, ARGS) \ + (IsDistinct ? CLASS::getDistinct ARGS : CLASS::get ARGS) + + switch (Code) { + default: // Default behavior: ignore. + break; + case bitc::METADATA_NAME: { + // Read name of the named metadata. + SmallString<8> Name(Record.begin(), Record.end()); + Record.clear(); + Code = Stream.ReadCode(); + + ++NumMDRecordLoaded; + unsigned NextBitCode = Stream.readRecord(Code, Record); + if (NextBitCode != bitc::METADATA_NAMED_NODE) + return error("METADATA_NAME not followed by METADATA_NAMED_NODE"); + + // Read named metadata elements. + unsigned Size = Record.size(); + NamedMDNode *NMD = TheModule.getOrInsertNamedMetadata(Name); + for (unsigned i = 0; i != Size; ++i) { + MDNode *MD = MetadataList.getMDNodeFwdRefOrNull(Record[i]); + if (!MD) + return error("Invalid record"); + NMD->addOperand(MD); + } + break; + } + case bitc::METADATA_OLD_FN_NODE: { + // FIXME: Remove in 4.0. + // This is a LocalAsMetadata record, the only type of function-local + // metadata. + if (Record.size() % 2 == 1) + return error("Invalid record"); + + // If this isn't a LocalAsMetadata record, we're dropping it. This used + // to be legal, but there's no upgrade path. + auto dropRecord = [&] { + MetadataList.assignValue(MDNode::get(Context, None), NextMetadataNo); + NextMetadataNo++; + }; + if (Record.size() != 2) { + dropRecord(); + break; + } + + Type *Ty = getTypeByID(Record[0]); + if (Ty->isMetadataTy() || Ty->isVoidTy()) { + dropRecord(); + break; + } + + MetadataList.assignValue( + LocalAsMetadata::get(ValueList.getValueFwdRef(Record[1], Ty)), + NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_OLD_NODE: { + // FIXME: Remove in 4.0. + if (Record.size() % 2 == 1) + return error("Invalid record"); + + unsigned Size = Record.size(); + SmallVector<Metadata *, 8> Elts; + for (unsigned i = 0; i != Size; i += 2) { + Type *Ty = getTypeByID(Record[i]); + if (!Ty) + return error("Invalid record"); + if (Ty->isMetadataTy()) + Elts.push_back(getMD(Record[i + 1])); + else if (!Ty->isVoidTy()) { + auto *MD = + ValueAsMetadata::get(ValueList.getValueFwdRef(Record[i + 1], Ty)); + assert(isa<ConstantAsMetadata>(MD) && + "Expected non-function-local metadata"); + Elts.push_back(MD); + } else + Elts.push_back(nullptr); + } + MetadataList.assignValue(MDNode::get(Context, Elts), NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_VALUE: { + if (Record.size() != 2) + return error("Invalid record"); + + Type *Ty = getTypeByID(Record[0]); + if (Ty->isMetadataTy() || Ty->isVoidTy()) + return error("Invalid record"); + + MetadataList.assignValue( + ValueAsMetadata::get(ValueList.getValueFwdRef(Record[1], Ty)), + NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_DISTINCT_NODE: + IsDistinct = true; + LLVM_FALLTHROUGH; + case bitc::METADATA_NODE: { + SmallVector<Metadata *, 8> Elts; + Elts.reserve(Record.size()); + for (unsigned ID : Record) + Elts.push_back(getMDOrNull(ID)); + MetadataList.assignValue(IsDistinct ? MDNode::getDistinct(Context, Elts) + : MDNode::get(Context, Elts), + NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_LOCATION: { + if (Record.size() != 5) + return error("Invalid record"); + + IsDistinct = Record[0]; + unsigned Line = Record[1]; + unsigned Column = Record[2]; + Metadata *Scope = getMD(Record[3]); + Metadata *InlinedAt = getMDOrNull(Record[4]); + MetadataList.assignValue( + GET_OR_DISTINCT(DILocation, (Context, Line, Column, Scope, InlinedAt)), + NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_GENERIC_DEBUG: { + if (Record.size() < 4) + return error("Invalid record"); + + IsDistinct = Record[0]; + unsigned Tag = Record[1]; + unsigned Version = Record[2]; + + if (Tag >= 1u << 16 || Version != 0) + return error("Invalid record"); + + auto *Header = getMDString(Record[3]); + SmallVector<Metadata *, 8> DwarfOps; + for (unsigned I = 4, E = Record.size(); I != E; ++I) + DwarfOps.push_back(getMDOrNull(Record[I])); + MetadataList.assignValue( + GET_OR_DISTINCT(GenericDINode, (Context, Tag, Header, DwarfOps)), + NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_SUBRANGE: { + if (Record.size() != 3) + return error("Invalid record"); + + IsDistinct = Record[0]; + MetadataList.assignValue( + GET_OR_DISTINCT(DISubrange, + (Context, Record[1], unrotateSign(Record[2]))), + NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_ENUMERATOR: { + if (Record.size() != 3) + return error("Invalid record"); + + IsDistinct = Record[0]; + MetadataList.assignValue( + GET_OR_DISTINCT(DIEnumerator, (Context, unrotateSign(Record[1]), + getMDString(Record[2]))), + NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_BASIC_TYPE: { + if (Record.size() != 6) + return error("Invalid record"); + + IsDistinct = Record[0]; + MetadataList.assignValue( + GET_OR_DISTINCT(DIBasicType, + (Context, Record[1], getMDString(Record[2]), Record[3], + Record[4], Record[5])), + NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_DERIVED_TYPE: { + if (Record.size() != 12) + return error("Invalid record"); + + IsDistinct = Record[0]; + DINode::DIFlags Flags = static_cast<DINode::DIFlags>(Record[10]); + MetadataList.assignValue( + GET_OR_DISTINCT(DIDerivedType, + (Context, Record[1], getMDString(Record[2]), + getMDOrNull(Record[3]), Record[4], + getDITypeRefOrNull(Record[5]), + getDITypeRefOrNull(Record[6]), Record[7], Record[8], + Record[9], Flags, getDITypeRefOrNull(Record[11]))), + NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_COMPOSITE_TYPE: { + if (Record.size() != 16) + return error("Invalid record"); + + // If we have a UUID and this is not a forward declaration, lookup the + // mapping. + IsDistinct = Record[0] & 0x1; + bool IsNotUsedInTypeRef = Record[0] >= 2; + unsigned Tag = Record[1]; + MDString *Name = getMDString(Record[2]); + Metadata *File = getMDOrNull(Record[3]); + unsigned Line = Record[4]; + Metadata *Scope = getDITypeRefOrNull(Record[5]); + Metadata *BaseType = nullptr; + uint64_t SizeInBits = Record[7]; + if (Record[8] > (uint64_t)std::numeric_limits<uint32_t>::max()) + return error("Alignment value is too large"); + uint32_t AlignInBits = Record[8]; + uint64_t OffsetInBits = 0; + DINode::DIFlags Flags = static_cast<DINode::DIFlags>(Record[10]); + Metadata *Elements = nullptr; + unsigned RuntimeLang = Record[12]; + Metadata *VTableHolder = nullptr; + Metadata *TemplateParams = nullptr; + auto *Identifier = getMDString(Record[15]); + // If this module is being parsed so that it can be ThinLTO imported + // into another module, composite types only need to be imported + // as type declarations (unless full type definitions requested). + // Create type declarations up front to save memory. Also, buildODRType + // handles the case where this is type ODRed with a definition needed + // by the importing module, in which case the existing definition is + // used. + if (IsImporting && !ImportFullTypeDefinitions && Identifier && + (Tag == dwarf::DW_TAG_enumeration_type || + Tag == dwarf::DW_TAG_class_type || + Tag == dwarf::DW_TAG_structure_type || + Tag == dwarf::DW_TAG_union_type)) { + Flags = Flags | DINode::FlagFwdDecl; + } else { + BaseType = getDITypeRefOrNull(Record[6]); + OffsetInBits = Record[9]; + Elements = getMDOrNull(Record[11]); + VTableHolder = getDITypeRefOrNull(Record[13]); + TemplateParams = getMDOrNull(Record[14]); + } + DICompositeType *CT = nullptr; + if (Identifier) + CT = DICompositeType::buildODRType( + Context, *Identifier, Tag, Name, File, Line, Scope, BaseType, + SizeInBits, AlignInBits, OffsetInBits, Flags, Elements, RuntimeLang, + VTableHolder, TemplateParams); + + // Create a node if we didn't get a lazy ODR type. + if (!CT) + CT = GET_OR_DISTINCT(DICompositeType, + (Context, Tag, Name, File, Line, Scope, BaseType, + SizeInBits, AlignInBits, OffsetInBits, Flags, + Elements, RuntimeLang, VTableHolder, TemplateParams, + Identifier)); + if (!IsNotUsedInTypeRef && Identifier) + MetadataList.addTypeRef(*Identifier, *cast<DICompositeType>(CT)); + + MetadataList.assignValue(CT, NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_SUBROUTINE_TYPE: { + if (Record.size() < 3 || Record.size() > 4) + return error("Invalid record"); + bool IsOldTypeRefArray = Record[0] < 2; + unsigned CC = (Record.size() > 3) ? Record[3] : 0; + + IsDistinct = Record[0] & 0x1; + DINode::DIFlags Flags = static_cast<DINode::DIFlags>(Record[1]); + Metadata *Types = getMDOrNull(Record[2]); + if (LLVM_UNLIKELY(IsOldTypeRefArray)) + Types = MetadataList.upgradeTypeRefArray(Types); + + MetadataList.assignValue( + GET_OR_DISTINCT(DISubroutineType, (Context, Flags, CC, Types)), + NextMetadataNo); + NextMetadataNo++; + break; + } + + case bitc::METADATA_MODULE: { + if (Record.size() != 6) + return error("Invalid record"); + + IsDistinct = Record[0]; + MetadataList.assignValue( + GET_OR_DISTINCT(DIModule, + (Context, getMDOrNull(Record[1]), + getMDString(Record[2]), getMDString(Record[3]), + getMDString(Record[4]), getMDString(Record[5]))), + NextMetadataNo); + NextMetadataNo++; + break; + } + + case bitc::METADATA_FILE: { + if (Record.size() != 3 && Record.size() != 5) + return error("Invalid record"); + + IsDistinct = Record[0]; + MetadataList.assignValue( + GET_OR_DISTINCT( + DIFile, + (Context, getMDString(Record[1]), getMDString(Record[2]), + Record.size() == 3 ? DIFile::CSK_None + : static_cast<DIFile::ChecksumKind>(Record[3]), + Record.size() == 3 ? nullptr : getMDString(Record[4]))), + NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_COMPILE_UNIT: { + if (Record.size() < 14 || Record.size() > 17) + return error("Invalid record"); + + // Ignore Record[0], which indicates whether this compile unit is + // distinct. It's always distinct. + IsDistinct = true; + auto *CU = DICompileUnit::getDistinct( + Context, Record[1], getMDOrNull(Record[2]), getMDString(Record[3]), + Record[4], getMDString(Record[5]), Record[6], getMDString(Record[7]), + Record[8], getMDOrNull(Record[9]), getMDOrNull(Record[10]), + getMDOrNull(Record[12]), getMDOrNull(Record[13]), + Record.size() <= 15 ? nullptr : getMDOrNull(Record[15]), + Record.size() <= 14 ? 0 : Record[14], + Record.size() <= 16 ? true : Record[16]); + + MetadataList.assignValue(CU, NextMetadataNo); + NextMetadataNo++; + + // Move the Upgrade the list of subprograms. + if (Metadata *SPs = getMDOrNullWithoutPlaceholders(Record[11])) + CUSubprograms.push_back({CU, SPs}); + break; + } + case bitc::METADATA_SUBPROGRAM: { + if (Record.size() < 18 || Record.size() > 20) + return error("Invalid record"); + + IsDistinct = + (Record[0] & 1) || Record[8]; // All definitions should be distinct. + // Version 1 has a Function as Record[15]. + // Version 2 has removed Record[15]. + // Version 3 has the Unit as Record[15]. + // Version 4 added thisAdjustment. + bool HasUnit = Record[0] >= 2; + if (HasUnit && Record.size() < 19) + return error("Invalid record"); + Metadata *CUorFn = getMDOrNull(Record[15]); + unsigned Offset = Record.size() >= 19 ? 1 : 0; + bool HasFn = Offset && !HasUnit; + bool HasThisAdj = Record.size() >= 20; + DISubprogram *SP = GET_OR_DISTINCT( + DISubprogram, (Context, + getDITypeRefOrNull(Record[1]), // scope + getMDString(Record[2]), // name + getMDString(Record[3]), // linkageName + getMDOrNull(Record[4]), // file + Record[5], // line + getMDOrNull(Record[6]), // type + Record[7], // isLocal + Record[8], // isDefinition + Record[9], // scopeLine + getDITypeRefOrNull(Record[10]), // containingType + Record[11], // virtuality + Record[12], // virtualIndex + HasThisAdj ? Record[19] : 0, // thisAdjustment + static_cast<DINode::DIFlags>(Record[13] // flags + ), + Record[14], // isOptimized + HasUnit ? CUorFn : nullptr, // unit + getMDOrNull(Record[15 + Offset]), // templateParams + getMDOrNull(Record[16 + Offset]), // declaration + getMDOrNull(Record[17 + Offset]) // variables + )); + MetadataList.assignValue(SP, NextMetadataNo); + NextMetadataNo++; + + // Upgrade sp->function mapping to function->sp mapping. + if (HasFn) { + if (auto *CMD = dyn_cast_or_null<ConstantAsMetadata>(CUorFn)) + if (auto *F = dyn_cast<Function>(CMD->getValue())) { + if (F->isMaterializable()) + // Defer until materialized; unmaterialized functions may not have + // metadata. + FunctionsWithSPs[F] = SP; + else if (!F->empty()) + F->setSubprogram(SP); + } + } + break; + } + case bitc::METADATA_LEXICAL_BLOCK: { + if (Record.size() != 5) + return error("Invalid record"); + + IsDistinct = Record[0]; + MetadataList.assignValue( + GET_OR_DISTINCT(DILexicalBlock, + (Context, getMDOrNull(Record[1]), + getMDOrNull(Record[2]), Record[3], Record[4])), + NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_LEXICAL_BLOCK_FILE: { + if (Record.size() != 4) + return error("Invalid record"); + + IsDistinct = Record[0]; + MetadataList.assignValue( + GET_OR_DISTINCT(DILexicalBlockFile, + (Context, getMDOrNull(Record[1]), + getMDOrNull(Record[2]), Record[3])), + NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_NAMESPACE: { + if (Record.size() != 5) + return error("Invalid record"); + + IsDistinct = Record[0] & 1; + bool ExportSymbols = Record[0] & 2; + MetadataList.assignValue( + GET_OR_DISTINCT(DINamespace, + (Context, getMDOrNull(Record[1]), + getMDOrNull(Record[2]), getMDString(Record[3]), + Record[4], ExportSymbols)), + NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_MACRO: { + if (Record.size() != 5) + return error("Invalid record"); + + IsDistinct = Record[0]; + MetadataList.assignValue( + GET_OR_DISTINCT(DIMacro, + (Context, Record[1], Record[2], getMDString(Record[3]), + getMDString(Record[4]))), + NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_MACRO_FILE: { + if (Record.size() != 5) + return error("Invalid record"); + + IsDistinct = Record[0]; + MetadataList.assignValue( + GET_OR_DISTINCT(DIMacroFile, + (Context, Record[1], Record[2], getMDOrNull(Record[3]), + getMDOrNull(Record[4]))), + NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_TEMPLATE_TYPE: { + if (Record.size() != 3) + return error("Invalid record"); + + IsDistinct = Record[0]; + MetadataList.assignValue(GET_OR_DISTINCT(DITemplateTypeParameter, + (Context, getMDString(Record[1]), + getDITypeRefOrNull(Record[2]))), + NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_TEMPLATE_VALUE: { + if (Record.size() != 5) + return error("Invalid record"); + + IsDistinct = Record[0]; + MetadataList.assignValue( + GET_OR_DISTINCT(DITemplateValueParameter, + (Context, Record[1], getMDString(Record[2]), + getDITypeRefOrNull(Record[3]), + getMDOrNull(Record[4]))), + NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_GLOBAL_VAR: { + if (Record.size() < 11 || Record.size() > 12) + return error("Invalid record"); + + IsDistinct = Record[0] & 1; + unsigned Version = Record[0] >> 1; + + if (Version == 1) { + MetadataList.assignValue( + GET_OR_DISTINCT(DIGlobalVariable, + (Context, getMDOrNull(Record[1]), + getMDString(Record[2]), getMDString(Record[3]), + getMDOrNull(Record[4]), Record[5], + getDITypeRefOrNull(Record[6]), Record[7], Record[8], + getMDOrNull(Record[10]), Record[11])), + NextMetadataNo); + NextMetadataNo++; + } else if (Version == 0) { + // Upgrade old metadata, which stored a global variable reference or a + // ConstantInt here. + Metadata *Expr = getMDOrNull(Record[9]); + uint32_t AlignInBits = 0; + if (Record.size() > 11) { + if (Record[11] > (uint64_t)std::numeric_limits<uint32_t>::max()) + return error("Alignment value is too large"); + AlignInBits = Record[11]; + } + GlobalVariable *Attach = nullptr; + if (auto *CMD = dyn_cast_or_null<ConstantAsMetadata>(Expr)) { + if (auto *GV = dyn_cast<GlobalVariable>(CMD->getValue())) { + Attach = GV; + Expr = nullptr; + } else if (auto *CI = dyn_cast<ConstantInt>(CMD->getValue())) { + Expr = DIExpression::get(Context, + {dwarf::DW_OP_constu, CI->getZExtValue(), + dwarf::DW_OP_stack_value}); + } else { + Expr = nullptr; + } + } + DIGlobalVariable *DGV = GET_OR_DISTINCT( + DIGlobalVariable, + (Context, getMDOrNull(Record[1]), getMDString(Record[2]), + getMDString(Record[3]), getMDOrNull(Record[4]), Record[5], + getDITypeRefOrNull(Record[6]), Record[7], Record[8], + getMDOrNull(Record[10]), AlignInBits)); + + DIGlobalVariableExpression *DGVE = nullptr; + if (Attach || Expr) + DGVE = DIGlobalVariableExpression::getDistinct(Context, DGV, Expr); + else + NeedUpgradeToDIGlobalVariableExpression = true; + if (Attach) + Attach->addDebugInfo(DGVE); + + auto *MDNode = Expr ? cast<Metadata>(DGVE) : cast<Metadata>(DGV); + MetadataList.assignValue(MDNode, NextMetadataNo); + NextMetadataNo++; + } else + return error("Invalid record"); + + break; + } + case bitc::METADATA_LOCAL_VAR: { + // 10th field is for the obseleted 'inlinedAt:' field. + if (Record.size() < 8 || Record.size() > 10) + return error("Invalid record"); + + IsDistinct = Record[0] & 1; + bool HasAlignment = Record[0] & 2; + // 2nd field used to be an artificial tag, either DW_TAG_auto_variable or + // DW_TAG_arg_variable, if we have alignment flag encoded it means, that + // this is newer version of record which doesn't have artifical tag. + bool HasTag = !HasAlignment && Record.size() > 8; + DINode::DIFlags Flags = static_cast<DINode::DIFlags>(Record[7 + HasTag]); + uint32_t AlignInBits = 0; + if (HasAlignment) { + if (Record[8 + HasTag] > (uint64_t)std::numeric_limits<uint32_t>::max()) + return error("Alignment value is too large"); + AlignInBits = Record[8 + HasTag]; + } + MetadataList.assignValue( + GET_OR_DISTINCT(DILocalVariable, + (Context, getMDOrNull(Record[1 + HasTag]), + getMDString(Record[2 + HasTag]), + getMDOrNull(Record[3 + HasTag]), Record[4 + HasTag], + getDITypeRefOrNull(Record[5 + HasTag]), + Record[6 + HasTag], Flags, AlignInBits)), + NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_EXPRESSION: { + if (Record.size() < 1) + return error("Invalid record"); + + IsDistinct = Record[0] & 1; + bool HasOpFragment = Record[0] & 2; + auto Elts = MutableArrayRef<uint64_t>(Record).slice(1); + if (!HasOpFragment) + if (unsigned N = Elts.size()) + if (N >= 3 && Elts[N - 3] == dwarf::DW_OP_bit_piece) + Elts[N - 3] = dwarf::DW_OP_LLVM_fragment; + + MetadataList.assignValue( + GET_OR_DISTINCT(DIExpression, (Context, makeArrayRef(Record).slice(1))), + NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_GLOBAL_VAR_EXPR: { + if (Record.size() != 3) + return error("Invalid record"); + + IsDistinct = Record[0]; + MetadataList.assignValue(GET_OR_DISTINCT(DIGlobalVariableExpression, + (Context, getMDOrNull(Record[1]), + getMDOrNull(Record[2]))), + NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_OBJC_PROPERTY: { + if (Record.size() != 8) + return error("Invalid record"); + + IsDistinct = Record[0]; + MetadataList.assignValue( + GET_OR_DISTINCT(DIObjCProperty, + (Context, getMDString(Record[1]), + getMDOrNull(Record[2]), Record[3], + getMDString(Record[4]), getMDString(Record[5]), + Record[6], getDITypeRefOrNull(Record[7]))), + NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_IMPORTED_ENTITY: { + if (Record.size() != 6) + return error("Invalid record"); + + IsDistinct = Record[0]; + MetadataList.assignValue( + GET_OR_DISTINCT(DIImportedEntity, + (Context, Record[1], getMDOrNull(Record[2]), + getDITypeRefOrNull(Record[3]), Record[4], + getMDString(Record[5]))), + NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_STRING_OLD: { + std::string String(Record.begin(), Record.end()); + + // Test for upgrading !llvm.loop. + HasSeenOldLoopTags |= mayBeOldLoopAttachmentTag(String); + ++NumMDStringLoaded; + Metadata *MD = MDString::get(Context, String); + MetadataList.assignValue(MD, NextMetadataNo); + NextMetadataNo++; + break; + } + case bitc::METADATA_STRINGS: { + auto CreateNextMDString = [&](StringRef Str) { + ++NumMDStringLoaded; + MetadataList.assignValue(MDString::get(Context, Str), NextMetadataNo); + NextMetadataNo++; + }; + if (Error Err = parseMetadataStrings(Record, Blob, CreateNextMDString)) + return Err; + break; + } + case bitc::METADATA_GLOBAL_DECL_ATTACHMENT: { + if (Record.size() % 2 == 0) + return error("Invalid record"); + unsigned ValueID = Record[0]; + if (ValueID >= ValueList.size()) + return error("Invalid record"); + if (auto *GO = dyn_cast<GlobalObject>(ValueList[ValueID])) + if (Error Err = parseGlobalObjectAttachment( + *GO, ArrayRef<uint64_t>(Record).slice(1))) + return Err; + break; + } + case bitc::METADATA_KIND: { + // Support older bitcode files that had METADATA_KIND records in a + // block with METADATA_BLOCK_ID. + if (Error Err = parseMetadataKindRecord(Record)) + return Err; + break; + } + } + return Error::success(); +#undef GET_OR_DISTINCT +} + +Error MetadataLoader::MetadataLoaderImpl::parseMetadataStrings( + ArrayRef<uint64_t> Record, StringRef Blob, + std::function<void(StringRef)> CallBack) { + // All the MDStrings in the block are emitted together in a single + // record. The strings are concatenated and stored in a blob along with + // their sizes. + if (Record.size() != 2) + return error("Invalid record: metadata strings layout"); + + unsigned NumStrings = Record[0]; + unsigned StringsOffset = Record[1]; + if (!NumStrings) + return error("Invalid record: metadata strings with no strings"); + if (StringsOffset > Blob.size()) + return error("Invalid record: metadata strings corrupt offset"); + + StringRef Lengths = Blob.slice(0, StringsOffset); + SimpleBitstreamCursor R(Lengths); + + StringRef Strings = Blob.drop_front(StringsOffset); + do { + if (R.AtEndOfStream()) + return error("Invalid record: metadata strings bad length"); + + unsigned Size = R.ReadVBR(6); + if (Strings.size() < Size) + return error("Invalid record: metadata strings truncated chars"); + + CallBack(Strings.slice(0, Size)); + Strings = Strings.drop_front(Size); + } while (--NumStrings); + + return Error::success(); +} + +Error MetadataLoader::MetadataLoaderImpl::parseGlobalObjectAttachment( + GlobalObject &GO, ArrayRef<uint64_t> Record) { + assert(Record.size() % 2 == 0); + for (unsigned I = 0, E = Record.size(); I != E; I += 2) { + auto K = MDKindMap.find(Record[I]); + if (K == MDKindMap.end()) + return error("Invalid ID"); + MDNode *MD = MetadataList.getMDNodeFwdRefOrNull(Record[I + 1]); + if (!MD) + return error("Invalid metadata attachment"); + GO.addMetadata(K->second, *MD); + } + return Error::success(); +} + +/// Parse metadata attachments. +Error MetadataLoader::MetadataLoaderImpl::parseMetadataAttachment( + Function &F, const SmallVectorImpl<Instruction *> &InstructionList) { + if (Stream.EnterSubBlock(bitc::METADATA_ATTACHMENT_ID)) + return error("Invalid record"); + + SmallVector<uint64_t, 64> Record; + PlaceholderQueue Placeholders; + + while (true) { + BitstreamEntry Entry = Stream.advanceSkippingSubblocks(); + + switch (Entry.Kind) { + case BitstreamEntry::SubBlock: // Handled for us already. + case BitstreamEntry::Error: + return error("Malformed block"); + case BitstreamEntry::EndBlock: + resolveForwardRefsAndPlaceholders(Placeholders); + return Error::success(); + case BitstreamEntry::Record: + // The interesting case. + break; + } + + // Read a metadata attachment record. + Record.clear(); + ++NumMDRecordLoaded; + switch (Stream.readRecord(Entry.ID, Record)) { + default: // Default behavior: ignore. + break; + case bitc::METADATA_ATTACHMENT: { + unsigned RecordLength = Record.size(); + if (Record.empty()) + return error("Invalid record"); + if (RecordLength % 2 == 0) { + // A function attachment. + if (Error Err = parseGlobalObjectAttachment(F, Record)) + return Err; + continue; + } + + // An instruction attachment. + Instruction *Inst = InstructionList[Record[0]]; + for (unsigned i = 1; i != RecordLength; i = i + 2) { + unsigned Kind = Record[i]; + DenseMap<unsigned, unsigned>::iterator I = MDKindMap.find(Kind); + if (I == MDKindMap.end()) + return error("Invalid ID"); + if (I->second == LLVMContext::MD_tbaa && StripTBAA) + continue; + + auto Idx = Record[i + 1]; + if (Idx < (MDStringRef.size() + GlobalMetadataBitPosIndex.size()) && + !MetadataList.lookup(Idx)) { + // Load the attachment if it is in the lazy-loadable range and hasn't + // been loaded yet. + lazyLoadOneMetadata(Idx, Placeholders); + resolveForwardRefsAndPlaceholders(Placeholders); + } + + Metadata *Node = MetadataList.getMetadataFwdRef(Idx); + if (isa<LocalAsMetadata>(Node)) + // Drop the attachment. This used to be legal, but there's no + // upgrade path. + break; + MDNode *MD = dyn_cast_or_null<MDNode>(Node); + if (!MD) + return error("Invalid metadata attachment"); + + if (HasSeenOldLoopTags && I->second == LLVMContext::MD_loop) + MD = upgradeInstructionLoopAttachment(*MD); + + if (I->second == LLVMContext::MD_tbaa) { + assert(!MD->isTemporary() && "should load MDs before attachments"); + MD = UpgradeTBAANode(*MD); + } + Inst->setMetadata(I->second, MD); + } + break; + } + } + } +} + +/// Parse a single METADATA_KIND record, inserting result in MDKindMap. +Error MetadataLoader::MetadataLoaderImpl::parseMetadataKindRecord( + SmallVectorImpl<uint64_t> &Record) { + if (Record.size() < 2) + return error("Invalid record"); + + unsigned Kind = Record[0]; + SmallString<8> Name(Record.begin() + 1, Record.end()); + + unsigned NewKind = TheModule.getMDKindID(Name.str()); + if (!MDKindMap.insert(std::make_pair(Kind, NewKind)).second) + return error("Conflicting METADATA_KIND records"); + return Error::success(); +} + +/// Parse the metadata kinds out of the METADATA_KIND_BLOCK. +Error MetadataLoader::MetadataLoaderImpl::parseMetadataKinds() { + if (Stream.EnterSubBlock(bitc::METADATA_KIND_BLOCK_ID)) + return error("Invalid record"); + + SmallVector<uint64_t, 64> Record; + + // Read all the records. + while (true) { + BitstreamEntry Entry = Stream.advanceSkippingSubblocks(); + + switch (Entry.Kind) { + case BitstreamEntry::SubBlock: // Handled for us already. + case BitstreamEntry::Error: + return error("Malformed block"); + case BitstreamEntry::EndBlock: + return Error::success(); + case BitstreamEntry::Record: + // The interesting case. + break; + } + + // Read a record. + Record.clear(); + ++NumMDRecordLoaded; + unsigned Code = Stream.readRecord(Entry.ID, Record); + switch (Code) { + default: // Default behavior: ignore. + break; + case bitc::METADATA_KIND: { + if (Error Err = parseMetadataKindRecord(Record)) + return Err; + break; + } + } + } +} + +MetadataLoader &MetadataLoader::operator=(MetadataLoader &&RHS) { + Pimpl = std::move(RHS.Pimpl); + return *this; +} +MetadataLoader::MetadataLoader(MetadataLoader &&RHS) + : Pimpl(std::move(RHS.Pimpl)) {} + +MetadataLoader::~MetadataLoader() = default; +MetadataLoader::MetadataLoader(BitstreamCursor &Stream, Module &TheModule, + BitcodeReaderValueList &ValueList, + bool IsImporting, + std::function<Type *(unsigned)> getTypeByID) + : Pimpl(llvm::make_unique<MetadataLoaderImpl>(Stream, TheModule, ValueList, + getTypeByID, IsImporting)) {} + +Error MetadataLoader::parseMetadata(bool ModuleLevel) { + return Pimpl->parseMetadata(ModuleLevel); +} + +bool MetadataLoader::hasFwdRefs() const { return Pimpl->hasFwdRefs(); } + +/// Return the given metadata, creating a replaceable forward reference if +/// necessary. +Metadata *MetadataLoader::getMetadataFwdRefOrLoad(unsigned Idx) { + return Pimpl->getMetadataFwdRefOrLoad(Idx); +} + +MDNode *MetadataLoader::getMDNodeFwdRefOrNull(unsigned Idx) { + return Pimpl->getMDNodeFwdRefOrNull(Idx); +} + +DISubprogram *MetadataLoader::lookupSubprogramForFunction(Function *F) { + return Pimpl->lookupSubprogramForFunction(F); +} + +Error MetadataLoader::parseMetadataAttachment( + Function &F, const SmallVectorImpl<Instruction *> &InstructionList) { + return Pimpl->parseMetadataAttachment(F, InstructionList); +} + +Error MetadataLoader::parseMetadataKinds() { + return Pimpl->parseMetadataKinds(); +} + +void MetadataLoader::setStripTBAA(bool StripTBAA) { + return Pimpl->setStripTBAA(StripTBAA); +} + +bool MetadataLoader::isStrippingTBAA() { return Pimpl->isStrippingTBAA(); } + +unsigned MetadataLoader::size() const { return Pimpl->size(); } +void MetadataLoader::shrinkTo(unsigned N) { return Pimpl->shrinkTo(N); } |