text: //===-- Bitcode/Writer/ValueEnumerator.h - Number values --------*- C++ -*-===//
  //
  //                     The LLVM Compiler Infrastructure
  //
  // This file is distributed under the University of Illinois Open Source
  // License. See LICENSE.TXT for details.
  //
  //===----------------------------------------------------------------------===//
  //
  // This class gives values and types Unique ID's.
  //
  //===----------------------------------------------------------------------===//
  
  #ifndef LLVM_LIB_BITCODE_WRITER_VALUEENUMERATOR_H
  #define LLVM_LIB_BITCODE_WRITER_VALUEENUMERATOR_H
  
  #include "llvm/ADT/DenseMap.h"
  #include "llvm/ADT/SmallVector.h"
  #include "llvm/ADT/UniqueVector.h"
  #include "llvm/IR/Attributes.h"
  #include "llvm/IR/Metadata.h"
  #include "llvm/IR/Type.h"
  #include "llvm/IR/UseListOrder.h"
  #include <vector>
  
  namespace llvm {
  
  class Type;
  class Value;
  class Instruction;
  class BasicBlock;
  class Comdat;
  class Function;
  class Module;
  class Metadata;
  class LocalAsMetadata;
  class MDNode;
  class NamedMDNode;
  class AttributeSet;
  class ValueSymbolTable;
  class MDSymbolTable;
  class raw_ostream;
  
  class ValueEnumerator {
  public:
    typedef std::vector<Type*> TypeList;
  
    // For each value, we remember its Value* and occurrence frequency.
    typedef std::vector<std::pair<const Value*, unsigned> > ValueList;
  
    UseListOrderStack UseListOrders;
  
  private:
    typedef DenseMap<Type*, unsigned> TypeMapType;
    TypeMapType TypeMap;
    TypeList Types;
  
    typedef DenseMap<const Value*, unsigned> ValueMapType;
    ValueMapType ValueMap;
    ValueList Values;
  
    typedef UniqueVector<const Comdat *> ComdatSetType;
    ComdatSetType Comdats;
  
    std::vector<const Metadata *> MDs;
    SmallVector<const LocalAsMetadata *, 8> FunctionLocalMDs;
    typedef DenseMap<const Metadata *, unsigned> MetadataMapType;
    MetadataMapType MetadataMap;
    bool HasMDString;
    bool HasDILocation;
    bool HasGenericDINode;
    bool ShouldPreserveUseListOrder;
  
    typedef DenseMap<AttributeSet, unsigned> AttributeGroupMapType;
    AttributeGroupMapType AttributeGroupMap;
    std::vector<AttributeSet> AttributeGroups;
  
    typedef DenseMap<AttributeSet, unsigned> AttributeMapType;
    AttributeMapType AttributeMap;
    std::vector<AttributeSet> Attribute;
  
    /// GlobalBasicBlockIDs - This map memoizes the basic block ID's referenced by
    /// the "getGlobalBasicBlockID" method.
    mutable DenseMap<const BasicBlock*, unsigned> GlobalBasicBlockIDs;
  
    typedef DenseMap<const Instruction*, unsigned> InstructionMapType;
    InstructionMapType InstructionMap;
    unsigned InstructionCount;
  
    /// BasicBlocks - This contains all the basic blocks for the currently
    /// incorporated function.  Their reverse mapping is stored in ValueMap.
    std::vector<const BasicBlock*> BasicBlocks;
  
    /// When a function is incorporated, this is the size of the Values list
    /// before incorporation.
    unsigned NumModuleValues;
  
    /// When a function is incorporated, this is the size of the Metadatas list
    /// before incorporation.
    unsigned NumModuleMDs;
  
    unsigned FirstFuncConstantID;
    unsigned FirstInstID;
  
    ValueEnumerator(const ValueEnumerator &) = delete;
    void operator=(const ValueEnumerator &) = delete;
  public:
    ValueEnumerator(const Module &M, bool ShouldPreserveUseListOrder);
  
    void dump() const;
    void print(raw_ostream &OS, const ValueMapType &Map, const char *Name) const;
    void print(raw_ostream &OS, const MetadataMapType &Map,
               const char *Name) const;
  
    unsigned getValueID(const Value *V) const;
    unsigned getMetadataID(const Metadata *MD) const {
      auto ID = getMetadataOrNullID(MD);
      assert(ID != 0 && "Metadata not in slotcalculator!");
      return ID - 1;
    }
    unsigned getMetadataOrNullID(const Metadata *MD) const {
      return MetadataMap.lookup(MD);
    }
    unsigned numMDs() const { return MDs.size(); }
  
    bool hasMDString() const { return HasMDString; }
    bool hasDILocation() const { return HasDILocation; }
    bool hasGenericDINode() const { return HasGenericDINode; }
  
    bool shouldPreserveUseListOrder() const { return ShouldPreserveUseListOrder; }
  
    unsigned getTypeID(Type *T) const {
      TypeMapType::const_iterator I = TypeMap.find(T);
      assert(I != TypeMap.end() && "Type not in ValueEnumerator!");
      return I->second-1;
    }
  
    unsigned getInstructionID(const Instruction *I) const;
    void setInstructionID(const Instruction *I);
  
    unsigned getAttributeID(AttributeSet PAL) const {
      if (PAL.isEmpty()) return 0;  // Null maps to zero.
      AttributeMapType::const_iterator I = AttributeMap.find(PAL);
      assert(I != AttributeMap.end() && "Attribute not in ValueEnumerator!");
      return I->second;
    }
  
    unsigned getAttributeGroupID(AttributeSet PAL) const {
      if (PAL.isEmpty()) return 0;  // Null maps to zero.
      AttributeGroupMapType::const_iterator I = AttributeGroupMap.find(PAL);
      assert(I != AttributeGroupMap.end() && "Attribute not in ValueEnumerator!");
      return I->second;
    }
  
    /// getFunctionConstantRange - Return the range of values that corresponds to
    /// function-local constants.
    void getFunctionConstantRange(unsigned &Start, unsigned &End) const {
      Start = FirstFuncConstantID;
      End = FirstInstID;
    }
  
    const ValueList &getValues() const { return Values; }
    const std::vector<const Metadata *> &getMDs() const { return MDs; }
    const SmallVectorImpl<const LocalAsMetadata *> &getFunctionLocalMDs() const {
      return FunctionLocalMDs;
    }
    const TypeList &getTypes() const { return Types; }
    const std::vector<const BasicBlock*> &getBasicBlocks() const {
      return BasicBlocks;
    }
    const std::vector<AttributeSet> &getAttributes() const {
      return Attribute;
    }
    const std::vector<AttributeSet> &getAttributeGroups() const {
      return AttributeGroups;
    }
  
    const ComdatSetType &getComdats() const { return Comdats; }
    unsigned getComdatID(const Comdat *C) const;
  
    /// getGlobalBasicBlockID - This returns the function-specific ID for the
    /// specified basic block.  This is relatively expensive information, so it
    /// should only be used by rare constructs such as address-of-label.
    unsigned getGlobalBasicBlockID(const BasicBlock *BB) const;
  
    /// incorporateFunction/purgeFunction - If you'd like to deal with a function,
    /// use these two methods to get its data into the ValueEnumerator!
    ///
    void incorporateFunction(const Function &F);
    void purgeFunction();
    uint64_t computeBitsRequiredForTypeIndicies() const;
  
  private:
    void OptimizeConstants(unsigned CstStart, unsigned CstEnd);
  
    void EnumerateMDNodeOperands(const MDNode *N);
    void EnumerateMetadata(const Metadata *MD);
    void EnumerateFunctionLocalMetadata(const LocalAsMetadata *Local);
    void EnumerateNamedMDNode(const NamedMDNode *NMD);
    void EnumerateValue(const Value *V);
    void EnumerateType(Type *T);
    void EnumerateOperandType(const Value *V);
    void EnumerateAttributes(AttributeSet PAL);
  
    void EnumerateValueSymbolTable(const ValueSymbolTable &ST);
    void EnumerateNamedMetadata(const Module &M);
  };
  
  } // End llvm namespace
  
  #endif
  