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Diffstat (limited to 'contrib/llvm/lib/Bitcode/Reader/BitcodeReader.h')
-rw-r--r-- | contrib/llvm/lib/Bitcode/Reader/BitcodeReader.h | 363 |
1 files changed, 363 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Bitcode/Reader/BitcodeReader.h b/contrib/llvm/lib/Bitcode/Reader/BitcodeReader.h new file mode 100644 index 0000000..7f7eb70 --- /dev/null +++ b/contrib/llvm/lib/Bitcode/Reader/BitcodeReader.h @@ -0,0 +1,363 @@ +//===- BitcodeReader.h - Internal BitcodeReader impl ------------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This header defines the BitcodeReader class. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_LIB_BITCODE_READER_BITCODEREADER_H +#define LLVM_LIB_BITCODE_READER_BITCODEREADER_H + +#include "llvm/ADT/DenseMap.h" +#include "llvm/Bitcode/BitstreamReader.h" +#include "llvm/Bitcode/LLVMBitCodes.h" +#include "llvm/IR/Attributes.h" +#include "llvm/IR/GVMaterializer.h" +#include "llvm/IR/Metadata.h" +#include "llvm/IR/OperandTraits.h" +#include "llvm/IR/TrackingMDRef.h" +#include "llvm/IR/Type.h" +#include "llvm/IR/ValueHandle.h" +#include <deque> +#include <system_error> +#include <vector> + +namespace llvm { + class Comdat; + class MemoryBuffer; + class LLVMContext; + +//===----------------------------------------------------------------------===// +// BitcodeReaderValueList Class +//===----------------------------------------------------------------------===// + +class BitcodeReaderValueList { + std::vector<WeakVH> ValuePtrs; + + /// ResolveConstants - As we resolve forward-referenced constants, we add + /// information about them to this vector. This allows us to resolve them in + /// bulk instead of resolving each reference at a time. See the code in + /// ResolveConstantForwardRefs for more information about this. + /// + /// The key of this vector is the placeholder constant, the value is the slot + /// number that holds the resolved value. + typedef std::vector<std::pair<Constant*, unsigned> > ResolveConstantsTy; + ResolveConstantsTy ResolveConstants; + LLVMContext &Context; +public: + BitcodeReaderValueList(LLVMContext &C) : Context(C) {} + ~BitcodeReaderValueList() { + assert(ResolveConstants.empty() && "Constants not resolved?"); + } + + // vector compatibility methods + unsigned size() const { return ValuePtrs.size(); } + void resize(unsigned N) { ValuePtrs.resize(N); } + void push_back(Value *V) { + ValuePtrs.push_back(V); + } + + void clear() { + assert(ResolveConstants.empty() && "Constants not resolved?"); + ValuePtrs.clear(); + } + + Value *operator[](unsigned i) const { + assert(i < ValuePtrs.size()); + return ValuePtrs[i]; + } + + Value *back() const { return ValuePtrs.back(); } + void pop_back() { ValuePtrs.pop_back(); } + bool empty() const { return ValuePtrs.empty(); } + void shrinkTo(unsigned N) { + assert(N <= size() && "Invalid shrinkTo request!"); + ValuePtrs.resize(N); + } + + Constant *getConstantFwdRef(unsigned Idx, Type *Ty); + Value *getValueFwdRef(unsigned Idx, Type *Ty); + + void AssignValue(Value *V, unsigned Idx); + + /// ResolveConstantForwardRefs - Once all constants are read, this method bulk + /// resolves any forward references. + void ResolveConstantForwardRefs(); +}; + + +//===----------------------------------------------------------------------===// +// BitcodeReaderMDValueList Class +//===----------------------------------------------------------------------===// + +class BitcodeReaderMDValueList { + unsigned NumFwdRefs; + bool AnyFwdRefs; + std::vector<TrackingMDRef> MDValuePtrs; + + LLVMContext &Context; +public: + BitcodeReaderMDValueList(LLVMContext &C) + : NumFwdRefs(0), AnyFwdRefs(false), Context(C) {} + + // vector compatibility methods + unsigned size() const { return MDValuePtrs.size(); } + void resize(unsigned N) { MDValuePtrs.resize(N); } + void push_back(Metadata *MD) { MDValuePtrs.emplace_back(MD); } + void clear() { MDValuePtrs.clear(); } + Metadata *back() const { return MDValuePtrs.back(); } + void pop_back() { MDValuePtrs.pop_back(); } + bool empty() const { return MDValuePtrs.empty(); } + + Metadata *operator[](unsigned i) const { + assert(i < MDValuePtrs.size()); + return MDValuePtrs[i]; + } + + void shrinkTo(unsigned N) { + assert(N <= size() && "Invalid shrinkTo request!"); + MDValuePtrs.resize(N); + } + + Metadata *getValueFwdRef(unsigned Idx); + void AssignValue(Metadata *MD, unsigned Idx); + void tryToResolveCycles(); +}; + +class BitcodeReader : public GVMaterializer { + LLVMContext &Context; + DiagnosticHandlerFunction DiagnosticHandler; + Module *TheModule; + std::unique_ptr<MemoryBuffer> Buffer; + std::unique_ptr<BitstreamReader> StreamFile; + BitstreamCursor Stream; + DataStreamer *LazyStreamer; + uint64_t NextUnreadBit; + bool SeenValueSymbolTable; + + std::vector<Type*> TypeList; + BitcodeReaderValueList ValueList; + BitcodeReaderMDValueList MDValueList; + std::vector<Comdat *> ComdatList; + SmallVector<Instruction *, 64> InstructionList; + + std::vector<std::pair<GlobalVariable*, unsigned> > GlobalInits; + std::vector<std::pair<GlobalAlias*, unsigned> > AliasInits; + std::vector<std::pair<Function*, unsigned> > FunctionPrefixes; + std::vector<std::pair<Function*, unsigned> > FunctionPrologues; + + SmallVector<Instruction*, 64> InstsWithTBAATag; + + /// MAttributes - The set of attributes by index. Index zero in the + /// file is for null, and is thus not represented here. As such all indices + /// are off by one. + std::vector<AttributeSet> MAttributes; + + /// \brief The set of attribute groups. + std::map<unsigned, AttributeSet> MAttributeGroups; + + /// FunctionBBs - While parsing a function body, this is a list of the basic + /// blocks for the function. + std::vector<BasicBlock*> FunctionBBs; + + // When reading the module header, this list is populated with functions that + // have bodies later in the file. + std::vector<Function*> FunctionsWithBodies; + + // When intrinsic functions are encountered which require upgrading they are + // stored here with their replacement function. + typedef std::vector<std::pair<Function*, Function*> > UpgradedIntrinsicMap; + UpgradedIntrinsicMap UpgradedIntrinsics; + + // Map the bitcode's custom MDKind ID to the Module's MDKind ID. + DenseMap<unsigned, unsigned> MDKindMap; + + // Several operations happen after the module header has been read, but + // before function bodies are processed. This keeps track of whether + // we've done this yet. + bool SeenFirstFunctionBody; + + /// DeferredFunctionInfo - When function bodies are initially scanned, this + /// map contains info about where to find deferred function body in the + /// stream. + DenseMap<Function*, uint64_t> DeferredFunctionInfo; + + /// These are basic blocks forward-referenced by block addresses. They are + /// inserted lazily into functions when they're loaded. The basic block ID is + /// its index into the vector. + DenseMap<Function *, std::vector<BasicBlock *>> BasicBlockFwdRefs; + std::deque<Function *> BasicBlockFwdRefQueue; + + /// UseRelativeIDs - Indicates that we are using a new encoding for + /// instruction operands where most operands in the current + /// FUNCTION_BLOCK are encoded relative to the instruction number, + /// for a more compact encoding. Some instruction operands are not + /// relative to the instruction ID: basic block numbers, and types. + /// Once the old style function blocks have been phased out, we would + /// not need this flag. + bool UseRelativeIDs; + + /// True if all functions will be materialized, negating the need to process + /// (e.g.) blockaddress forward references. + bool WillMaterializeAllForwardRefs; + + /// Functions that have block addresses taken. This is usually empty. + SmallPtrSet<const Function *, 4> BlockAddressesTaken; + +public: + std::error_code Error(BitcodeError E, const Twine &Message); + std::error_code Error(BitcodeError E); + std::error_code Error(const Twine &Message); + + explicit BitcodeReader(MemoryBuffer *buffer, LLVMContext &C, + DiagnosticHandlerFunction DiagnosticHandler); + explicit BitcodeReader(DataStreamer *streamer, LLVMContext &C, + DiagnosticHandlerFunction DiagnosticHandler); + ~BitcodeReader() { FreeState(); } + + std::error_code materializeForwardReferencedFunctions(); + + void FreeState(); + + void releaseBuffer(); + + bool isDematerializable(const GlobalValue *GV) const override; + std::error_code materialize(GlobalValue *GV) override; + std::error_code MaterializeModule(Module *M) override; + std::vector<StructType *> getIdentifiedStructTypes() const override; + void Dematerialize(GlobalValue *GV) override; + + /// @brief Main interface to parsing a bitcode buffer. + /// @returns true if an error occurred. + std::error_code ParseBitcodeInto(Module *M); + + /// @brief Cheap mechanism to just extract module triple + /// @returns true if an error occurred. + ErrorOr<std::string> parseTriple(); + + static uint64_t decodeSignRotatedValue(uint64_t V); + +private: + std::vector<StructType *> IdentifiedStructTypes; + StructType *createIdentifiedStructType(LLVMContext &Context, StringRef Name); + StructType *createIdentifiedStructType(LLVMContext &Context); + + Type *getTypeByID(unsigned ID); + Value *getFnValueByID(unsigned ID, Type *Ty) { + if (Ty && Ty->isMetadataTy()) + return MetadataAsValue::get(Ty->getContext(), getFnMetadataByID(ID)); + return ValueList.getValueFwdRef(ID, Ty); + } + Metadata *getFnMetadataByID(unsigned ID) { + return MDValueList.getValueFwdRef(ID); + } + BasicBlock *getBasicBlock(unsigned ID) const { + if (ID >= FunctionBBs.size()) return nullptr; // Invalid ID + return FunctionBBs[ID]; + } + AttributeSet getAttributes(unsigned i) const { + if (i-1 < MAttributes.size()) + return MAttributes[i-1]; + return AttributeSet(); + } + + /// getValueTypePair - Read a value/type pair out of the specified record from + /// slot 'Slot'. Increment Slot past the number of slots used in the record. + /// Return true on failure. + bool getValueTypePair(SmallVectorImpl<uint64_t> &Record, unsigned &Slot, + unsigned InstNum, Value *&ResVal) { + if (Slot == Record.size()) return true; + unsigned ValNo = (unsigned)Record[Slot++]; + // Adjust the ValNo, if it was encoded relative to the InstNum. + if (UseRelativeIDs) + ValNo = InstNum - ValNo; + if (ValNo < InstNum) { + // If this is not a forward reference, just return the value we already + // have. + ResVal = getFnValueByID(ValNo, nullptr); + return ResVal == nullptr; + } else if (Slot == Record.size()) { + return true; + } + + unsigned TypeNo = (unsigned)Record[Slot++]; + ResVal = getFnValueByID(ValNo, getTypeByID(TypeNo)); + return ResVal == nullptr; + } + + /// popValue - Read a value out of the specified record from slot 'Slot'. + /// Increment Slot past the number of slots used by the value in the record. + /// Return true if there is an error. + bool popValue(SmallVectorImpl<uint64_t> &Record, unsigned &Slot, + unsigned InstNum, Type *Ty, Value *&ResVal) { + if (getValue(Record, Slot, InstNum, Ty, ResVal)) + return true; + // All values currently take a single record slot. + ++Slot; + return false; + } + + /// getValue -- Like popValue, but does not increment the Slot number. + bool getValue(SmallVectorImpl<uint64_t> &Record, unsigned Slot, + unsigned InstNum, Type *Ty, Value *&ResVal) { + ResVal = getValue(Record, Slot, InstNum, Ty); + return ResVal == nullptr; + } + + /// getValue -- Version of getValue that returns ResVal directly, + /// or 0 if there is an error. + Value *getValue(SmallVectorImpl<uint64_t> &Record, unsigned Slot, + unsigned InstNum, Type *Ty) { + if (Slot == Record.size()) return nullptr; + unsigned ValNo = (unsigned)Record[Slot]; + // Adjust the ValNo, if it was encoded relative to the InstNum. + if (UseRelativeIDs) + ValNo = InstNum - ValNo; + return getFnValueByID(ValNo, Ty); + } + + /// getValueSigned -- Like getValue, but decodes signed VBRs. + Value *getValueSigned(SmallVectorImpl<uint64_t> &Record, unsigned Slot, + unsigned InstNum, Type *Ty) { + if (Slot == Record.size()) return nullptr; + unsigned ValNo = (unsigned)decodeSignRotatedValue(Record[Slot]); + // Adjust the ValNo, if it was encoded relative to the InstNum. + if (UseRelativeIDs) + ValNo = InstNum - ValNo; + return getFnValueByID(ValNo, Ty); + } + + std::error_code ParseAttrKind(uint64_t Code, Attribute::AttrKind *Kind); + std::error_code ParseModule(bool Resume); + std::error_code ParseAttributeBlock(); + std::error_code ParseAttributeGroupBlock(); + std::error_code ParseTypeTable(); + std::error_code ParseTypeTableBody(); + + std::error_code ParseValueSymbolTable(); + std::error_code ParseConstants(); + std::error_code RememberAndSkipFunctionBody(); + std::error_code ParseFunctionBody(Function *F); + std::error_code GlobalCleanup(); + std::error_code ResolveGlobalAndAliasInits(); + std::error_code ParseMetadata(); + std::error_code ParseMetadataAttachment(); + ErrorOr<std::string> parseModuleTriple(); + std::error_code ParseUseLists(); + std::error_code InitStream(); + std::error_code InitStreamFromBuffer(); + std::error_code InitLazyStream(); + std::error_code FindFunctionInStream( + Function *F, + DenseMap<Function *, uint64_t>::iterator DeferredFunctionInfoIterator); +}; + +} // End llvm namespace + +#endif |