DwarfCompileUnit.h

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//===-- llvm/CodeGen/DwarfCompileUnit.h - Dwarf Compile Unit ---*- C++ -*--===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains support for writing dwarf compile unit.
//
//===----------------------------------------------------------------------===//

#ifndef CODEGEN_ASMPRINTER_DWARFCOMPILEUNIT_H
#define CODEGEN_ASMPRINTER_DWARFCOMPILEUNIT_H

#include "DIE.h"
#include "DwarfDebug.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/Optional.h"
#include "llvm/ADT/OwningPtr.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/DebugInfo.h"
#include "llvm/MC/MCExpr.h"

namespace llvm {

class MachineLocation;
class MachineOperand;
class ConstantInt;
class ConstantFP;
class DbgVariable;

//===----------------------------------------------------------------------===//
/// CompileUnit - This dwarf writer support class manages information associated
/// with a source file.
class CompileUnit {
  /// UniqueID - a numeric ID unique among all CUs in the module
  ///
  unsigned UniqueID;

  /// Node - MDNode for the compile unit.
  DICompileUnit Node;

  /// CUDie - Compile unit debug information entry.
  ///
  const OwningPtr<DIE> CUDie;

  /// Asm - Target of Dwarf emission.
  AsmPrinter *Asm;

  // Holders for some common dwarf information.
  DwarfDebug *DD;
  DwarfUnits *DU;

  /// IndexTyDie - An anonymous type for index type.  Owned by CUDie.
  DIE *IndexTyDie;

  /// MDNodeToDieMap - Tracks the mapping of unit level debug information
  /// variables to debug information entries.
  DenseMap<const MDNode *, DIE *> MDNodeToDieMap;

  /// MDNodeToDIEEntryMap - Tracks the mapping of unit level debug information
  /// descriptors to debug information entries using a DIEEntry proxy.
  DenseMap<const MDNode *, DIEEntry *> MDNodeToDIEEntryMap;

  /// GlobalNames - A map of globally visible named entities for this unit.
  ///
  StringMap<DIE *> GlobalNames;

  /// GlobalTypes - A map of globally visible types for this unit.
  ///
  StringMap<DIE *> GlobalTypes;

  /// AccelNames - A map of names for the name accelerator table.
  ///
  StringMap<std::vector<DIE *> > AccelNames;
  StringMap<std::vector<DIE *> > AccelObjC;
  StringMap<std::vector<DIE *> > AccelNamespace;
  StringMap<std::vector<std::pair<DIE *, unsigned> > > AccelTypes;

  /// DIEBlocks - A list of all the DIEBlocks in use.
  std::vector<DIEBlock *> DIEBlocks;

  /// ContainingTypeMap - This map is used to keep track of subprogram DIEs that
  /// need DW_AT_containing_type attribute. This attribute points to a DIE that
  /// corresponds to the MDNode mapped with the subprogram DIE.
  DenseMap<DIE *, const MDNode *> ContainingTypeMap;

  // DIEValueAllocator - All DIEValues are allocated through this allocator.
  BumpPtrAllocator DIEValueAllocator;

  // DIEIntegerOne - A preallocated DIEValue because 1 is used frequently.
  DIEInteger *DIEIntegerOne;

public:
  CompileUnit(unsigned UID, DIE *D, DICompileUnit CU, AsmPrinter *A,
              DwarfDebug *DW, DwarfUnits *DWU);
  ~CompileUnit();

  // Accessors.
  unsigned getUniqueID() const { return UniqueID; }
  uint16_t getLanguage() const { return Node.getLanguage(); }
  DICompileUnit getNode() const { return Node; }
  DIE *getCUDie() const { return CUDie.get(); }
  const StringMap<DIE *> &getGlobalNames() const { return GlobalNames; }
  const StringMap<DIE *> &getGlobalTypes() const { return GlobalTypes; }

  const StringMap<std::vector<DIE *> > &getAccelNames() const {
    return AccelNames;
  }
  const StringMap<std::vector<DIE *> > &getAccelObjC() const {
    return AccelObjC;
  }
  const StringMap<std::vector<DIE *> > &getAccelNamespace() const {
    return AccelNamespace;
  }
  const StringMap<std::vector<std::pair<DIE *, unsigned> > > &
  getAccelTypes() const {
    return AccelTypes;
  }

  unsigned getDebugInfoOffset() const { return DebugInfoOffset; }
  void setDebugInfoOffset(unsigned DbgInfoOff) { DebugInfoOffset = DbgInfoOff; }

  /// hasContent - Return true if this compile unit has something to write out.
  ///
  bool hasContent() const { return !CUDie->getChildren().empty(); }

  /// getParentContextString - Get a string containing the language specific
  /// context for a global name.
  std::string getParentContextString(DIScope Context) const;

  /// addGlobalName - Add a new global entity to the compile unit.
  ///
  void addGlobalName(StringRef Name, DIE *Die, DIScope Context);

  /// addGlobalType - Add a new global type to the compile unit.
  ///
  void addGlobalType(DIType Ty);

  /// addPubTypes - Add a set of types from the subprogram to the global types.
  void addPubTypes(DISubprogram SP);

  /// addAccelName - Add a new name to the name accelerator table.
  void addAccelName(StringRef Name, DIE *Die);

  /// addAccelObjC - Add a new name to the ObjC accelerator table.
  void addAccelObjC(StringRef Name, DIE *Die);

  /// addAccelNamespace - Add a new name to the namespace accelerator table.
  void addAccelNamespace(StringRef Name, DIE *Die);

  /// addAccelType - Add a new type to the type accelerator table.
  void addAccelType(StringRef Name, std::pair<DIE *, unsigned> Die);

  /// getDIE - Returns the debug information entry map slot for the
  /// specified debug variable. We delegate the request to DwarfDebug
  /// when the MDNode can be part of the type system, since DIEs for
  /// the type system can be shared across CUs and the mappings are
  /// kept in DwarfDebug.
  DIE *getDIE(DIDescriptor D) const;

  DIEBlock *getDIEBlock() { return new (DIEValueAllocator) DIEBlock(); }

  /// insertDIE - Insert DIE into the map. We delegate the request to DwarfDebug
  /// when the MDNode can be part of the type system, since DIEs for
  /// the type system can be shared across CUs and the mappings are
  /// kept in DwarfDebug.
  void insertDIE(DIDescriptor Desc, DIE *D);

  /// addDie - Adds or interns the DIE to the compile unit.
  ///
  void addDie(DIE *Buffer) { CUDie->addChild(Buffer); }

  /// addFlag - Add a flag that is true to the DIE.
  void addFlag(DIE *Die, dwarf::Attribute Attribute);

  /// addUInt - Add an unsigned integer attribute data and value.
  ///
  void addUInt(DIE *Die, dwarf::Attribute Attribute, Optional<dwarf::Form> Form,
               uint64_t Integer);

  void addUInt(DIEBlock *Block, dwarf::Form Form, uint64_t Integer);

  /// addSInt - Add an signed integer attribute data and value.
  ///
  void addSInt(DIE *Die, dwarf::Attribute Attribute, Optional<dwarf::Form> Form,
               int64_t Integer);

  void addSInt(DIEBlock *Die, Optional<dwarf::Form> Form, int64_t Integer);

  /// addString - Add a string attribute data and value.
  ///
  void addString(DIE *Die, dwarf::Attribute Attribute, const StringRef Str);

  /// addLocalString - Add a string attribute data and value.
  ///
  void addLocalString(DIE *Die, dwarf::Attribute Attribute, const StringRef Str);

  /// addExpr - Add a Dwarf expression attribute data and value.
  ///
  void addExpr(DIEBlock *Die, dwarf::Form Form, const MCExpr *Expr);

  /// addLabel - Add a Dwarf label attribute data and value.
  ///
  void addLabel(DIE *Die, dwarf::Attribute Attribute, dwarf::Form Form,
                const MCSymbol *Label);

  void addLabel(DIEBlock *Die, dwarf::Form Form, const MCSymbol *Label);

  /// addLabelAddress - Add a dwarf label attribute data and value using
  /// either DW_FORM_addr or DW_FORM_GNU_addr_index.
  ///
  void addLabelAddress(DIE *Die, dwarf::Attribute Attribute, MCSymbol *Label);

  /// addOpAddress - Add a dwarf op address data and value using the
  /// form given and an op of either DW_FORM_addr or DW_FORM_GNU_addr_index.
  ///
  void addOpAddress(DIEBlock *Die, const MCSymbol *Label);

  /// addDelta - Add a label delta attribute data and value.
  ///
  void addDelta(DIE *Die, dwarf::Attribute Attribute, dwarf::Form Form, const MCSymbol *Hi,
                const MCSymbol *Lo);

  /// addDIEEntry - Add a DIE attribute data and value.
  ///
  void addDIEEntry(DIE *Die, dwarf::Attribute Attribute, DIE *Entry);

  /// addDIEEntry - Add a DIE attribute data and value.
  ///
  void addDIEEntry(DIE *Die, dwarf::Attribute Attribute, DIEEntry *Entry);

  /// addBlock - Add block data.
  ///
  void addBlock(DIE *Die, dwarf::Attribute Attribute, DIEBlock *Block);

  /// addSourceLine - Add location information to specified debug information
  /// entry.
  void addSourceLine(DIE *Die, DIVariable V);
  void addSourceLine(DIE *Die, DIGlobalVariable G);
  void addSourceLine(DIE *Die, DISubprogram SP);
  void addSourceLine(DIE *Die, DIType Ty);
  void addSourceLine(DIE *Die, DINameSpace NS);
  void addSourceLine(DIE *Die, DIObjCProperty Ty);

  /// addAddress - Add an address attribute to a die based on the location
  /// provided.
  void addAddress(DIE *Die, dwarf::Attribute Attribute, const MachineLocation &Location,
                  bool Indirect = false);

  /// addConstantValue - Add constant value entry in variable DIE.
  void addConstantValue(DIE *Die, const MachineOperand &MO, DIType Ty);
  void addConstantValue(DIE *Die, const ConstantInt *CI, bool Unsigned);
  void addConstantValue(DIE *Die, const APInt &Val, bool Unsigned);

  /// addConstantFPValue - Add constant value entry in variable DIE.
  void addConstantFPValue(DIE *Die, const MachineOperand &MO);
  void addConstantFPValue(DIE *Die, const ConstantFP *CFP);

  /// addTemplateParams - Add template parameters in buffer.
  void addTemplateParams(DIE &Buffer, DIArray TParams);

  /// addRegisterOp - Add register operand.
  void addRegisterOp(DIEBlock *TheDie, unsigned Reg);

  /// addRegisterOffset - Add register offset.
  void addRegisterOffset(DIEBlock *TheDie, unsigned Reg, int64_t Offset);

  /// addComplexAddress - Start with the address based on the location provided,
  /// and generate the DWARF information necessary to find the actual variable
  /// (navigating the extra location information encoded in the type) based on
  /// the starting location.  Add the DWARF information to the die.
  ///
  void addComplexAddress(const DbgVariable &DV, DIE *Die, dwarf::Attribute Attribute,
                         const MachineLocation &Location);

  // FIXME: Should be reformulated in terms of addComplexAddress.
  /// addBlockByrefAddress - Start with the address based on the location
  /// provided, and generate the DWARF information necessary to find the
  /// actual Block variable (navigating the Block struct) based on the
  /// starting location.  Add the DWARF information to the die.  Obsolete,
  /// please use addComplexAddress instead.
  ///
  void addBlockByrefAddress(const DbgVariable &DV, DIE *Die, dwarf::Attribute Attribute,
                            const MachineLocation &Location);

  /// addVariableAddress - Add DW_AT_location attribute for a
  /// DbgVariable based on provided MachineLocation.
  void addVariableAddress(const DbgVariable &DV, DIE *Die,
                          MachineLocation Location);

  /// addType - Add a new type attribute to the specified entity. This takes
  /// and attribute parameter because DW_AT_friend attributes are also
  /// type references.
  void addType(DIE *Entity, DIType Ty, dwarf::Attribute Attribute = dwarf::DW_AT_type);

  /// getOrCreateNameSpace - Create a DIE for DINameSpace.
  DIE *getOrCreateNameSpace(DINameSpace NS);

  /// getOrCreateSubprogramDIE - Create new DIE using SP.
  DIE *getOrCreateSubprogramDIE(DISubprogram SP);

  /// getOrCreateTypeDIE - Find existing DIE or create new DIE for the
  /// given DIType.
  DIE *getOrCreateTypeDIE(const MDNode *N);

  /// getOrCreateContextDIE - Get context owner's DIE.
  DIE *getOrCreateContextDIE(DIScope Context);

  /// createGlobalVariableDIE - create global variable DIE.
  void createGlobalVariableDIE(DIGlobalVariable GV);

  /// constructContainingTypeDIEs - Construct DIEs for types that contain
  /// vtables.
  void constructContainingTypeDIEs();

  /// constructVariableDIE - Construct a DIE for the given DbgVariable.
  DIE *constructVariableDIE(DbgVariable &DV, bool isScopeAbstract);

  /// Create a DIE with the given Tag, add the DIE to its parent, and
  /// call insertDIE if MD is not null.
  DIE *createAndAddDIE(unsigned Tag, DIE &Parent, DIDescriptor N = DIDescriptor());

  /// Compute the size of a header for this unit, not including the initial
  /// length field.
  unsigned getHeaderSize() const {
    return sizeof(int16_t) + // DWARF version number
           sizeof(int32_t) + // Offset Into Abbrev. Section
           sizeof(int8_t);   // Pointer Size (in bytes)
  }

  /// Emit the header for this unit, not including the initial length field.
  void emitHeader(const MCSection *ASection, const MCSymbol *ASectionSym);

private:
  /// constructTypeDIE - Construct basic type die from DIBasicType.
  void constructTypeDIE(DIE &Buffer, DIBasicType BTy);

  /// constructTypeDIE - Construct derived type die from DIDerivedType.
  void constructTypeDIE(DIE &Buffer, DIDerivedType DTy);

  /// constructTypeDIE - Construct type DIE from DICompositeType.
  void constructTypeDIE(DIE &Buffer, DICompositeType CTy);

  /// constructSubrangeDIE - Construct subrange DIE from DISubrange.
  void constructSubrangeDIE(DIE &Buffer, DISubrange SR, DIE *IndexTy);

  /// constructArrayTypeDIE - Construct array type DIE from DICompositeType.
  void constructArrayTypeDIE(DIE &Buffer, DICompositeType CTy);

  /// constructEnumTypeDIE - Construct enum type DIE from DIEnumerator.
  void constructEnumTypeDIE(DIE &Buffer, DICompositeType CTy);

  /// constructMemberDIE - Construct member DIE from DIDerivedType.
  void constructMemberDIE(DIE &Buffer, DIDerivedType DT);

  /// constructTemplateTypeParameterDIE - Construct new DIE for the given
  /// DITemplateTypeParameter.
  void constructTemplateTypeParameterDIE(DIE &Buffer,
                                         DITemplateTypeParameter TP);

  /// constructTemplateValueParameterDIE - Construct new DIE for the given
  /// DITemplateValueParameter.
  void constructTemplateValueParameterDIE(DIE &Buffer,
                                          DITemplateValueParameter TVP);

  /// getOrCreateStaticMemberDIE - Create new static data member DIE.
  DIE *getOrCreateStaticMemberDIE(DIDerivedType DT);

  /// Offset of the CUDie from beginning of debug info section.
  unsigned DebugInfoOffset;

  /// getLowerBoundDefault - Return the default lower bound for an array. If the
  /// DWARF version doesn't handle the language, return -1.
  int64_t getDefaultLowerBound() const;

  /// getDIEEntry - Returns the debug information entry for the specified
  /// debug variable.
  DIEEntry *getDIEEntry(const MDNode *N) const {
    return MDNodeToDIEEntryMap.lookup(N);
  }

  /// insertDIEEntry - Insert debug information entry into the map.
  void insertDIEEntry(const MDNode *N, DIEEntry *E) {
    MDNodeToDIEEntryMap.insert(std::make_pair(N, E));
  }

  // getIndexTyDie - Get an anonymous type for index type.
  DIE *getIndexTyDie() { return IndexTyDie; }

  // setIndexTyDie - Set D as anonymous type for index which can be reused
  // later.
  void setIndexTyDie(DIE *D) { IndexTyDie = D; }

  /// createDIEEntry - Creates a new DIEEntry to be a proxy for a debug
  /// information entry.
  DIEEntry *createDIEEntry(DIE *Entry);

  /// resolve - Look in the DwarfDebug map for the MDNode that
  /// corresponds to the reference.
  template <typename T> T resolve(DIRef<T> Ref) const {
    return DD->resolve(Ref);
  }
};

} // end llvm namespace
#endif