path: root/lib/CodeGen/AsmPrinter/DwarfDebug.h

//===-- llvm/CodeGen/DwarfDebug.h - Dwarf Debug Framework ------*- 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 debug info into asm files.
//
//===----------------------------------------------------------------------===//

#ifndef CODEGEN_ASMPRINTER_DWARFDEBUG_H__
#define CODEGEN_ASMPRINTER_DWARFDEBUG_H__

#include "llvm/CodeGen/AsmPrinter.h"
#include "DIE.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/FoldingSet.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/UniqueVector.h"
#include "llvm/Support/Allocator.h"

namespace llvm {

class CompileUnit;
class DbgConcreteScope;
class DbgScope;
class DbgVariable;
class MachineFrameInfo;
class MachineLocation;
class MachineModuleInfo;
class MCAsmInfo;
class DIEAbbrev;
class DIE;
class DIEBlock;
class DIEEntry;

class DIEnumerator;
class DIDescriptor;
class DIVariable;
class DIGlobal;
class DIGlobalVariable;
class DISubprogram;
class DIBasicType;
class DIDerivedType;
class DIType;
class DINameSpace;
class DISubrange;
class DICompositeType;

//===----------------------------------------------------------------------===//
/// SrcLineInfo - This class is used to record source line correspondence.
///
class SrcLineInfo {
  unsigned Line;                     // Source line number.
  unsigned Column;                   // Source column.
  unsigned SourceID;                 // Source ID number.
  MCSymbol *Label;                   // Label in code ID number.
public:
  SrcLineInfo(unsigned L, unsigned C, unsigned S, MCSymbol *label)
    : Line(L), Column(C), SourceID(S), Label(label) {}

  // Accessors
  unsigned getLine() const { return Line; }
  unsigned getColumn() const { return Column; }
  unsigned getSourceID() const { return SourceID; }
  MCSymbol *getLabel() const { return Label; }
};

class DwarfDebug {
  /// Asm - Target of Dwarf emission.
  AsmPrinter *Asm;

  /// MMI - Collected machine module information.
  MachineModuleInfo *MMI;

  //===--------------------------------------------------------------------===//
  // Attributes used to construct specific Dwarf sections.
  //

  /// ModuleCU - All DIEs are inserted in ModuleCU.
  CompileUnit *ModuleCU;

  /// AbbreviationsSet - Used to uniquely define abbreviations.
  ///
  FoldingSet<DIEAbbrev> AbbreviationsSet;

  /// Abbreviations - A list of all the unique abbreviations in use.
  ///
  std::vector<DIEAbbrev *> Abbreviations;

  /// DirectoryIdMap - Directory name to directory id map.
  ///
  StringMap<unsigned> DirectoryIdMap;

  /// DirectoryNames - A list of directory names.
  SmallVector<std::string, 8> DirectoryNames;

  /// SourceFileIdMap - Source file name to source file id map.
  ///
  StringMap<unsigned> SourceFileIdMap;

  /// SourceFileNames - A list of source file names.
  SmallVector<std::string, 8> SourceFileNames;

  /// SourceIdMap - Source id map, i.e. pair of directory id and source file
  /// id mapped to a unique id.
  DenseMap<std::pair<unsigned, unsigned>, unsigned> SourceIdMap;

  /// SourceIds - Reverse map from source id to directory id + file id pair.
  ///
  SmallVector<std::pair<unsigned, unsigned>, 8> SourceIds;

  /// Lines - List of source line correspondence.
  std::vector<SrcLineInfo> Lines;

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

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

  /// StringPool - A String->Symbol mapping of strings used by indirect
  /// references.
  StringMap<std::pair<MCSymbol*, unsigned> > StringPool;
  unsigned NextStringPoolNumber;
  
  MCSymbol *getStringPoolEntry(StringRef Str);

  /// SectionMap - Provides a unique id per text section.
  ///
  UniqueVector<const MCSection*> SectionMap;

  /// SectionSourceLines - Tracks line numbers per text section.
  ///
  std::vector<std::vector<SrcLineInfo> > SectionSourceLines;

  // CurrentFnDbgScope - Top level scope for the current function.
  //
  DbgScope *CurrentFnDbgScope;
  
  /// DbgScopeMap - Tracks the scopes in the current function.  Owns the
  /// contained DbgScope*s.
  ///
  DenseMap<MDNode *, DbgScope *> DbgScopeMap;

  /// ConcreteScopes - Tracks the concrete scopees in the current function.
  /// These scopes are also included in DbgScopeMap.
  DenseMap<MDNode *, DbgScope *> ConcreteScopes;

  /// AbstractScopes - Tracks the abstract scopes a module. These scopes are
  /// not included DbgScopeMap.  AbstractScopes owns its DbgScope*s.
  DenseMap<MDNode *, DbgScope *> AbstractScopes;

  /// AbstractScopesList - Tracks abstract scopes constructed while processing
  /// a function. This list is cleared during endFunction().
  SmallVector<DbgScope *, 4>AbstractScopesList;

  /// AbstractVariables - Collection on abstract variables.  Owned by the
  /// DbgScopes in AbstractScopes.
  DenseMap<MDNode *, DbgVariable *> AbstractVariables;

  /// DbgValueStartMap - Tracks starting scope of variable DIEs.
  /// If the scope of an object begins sometime after the low pc value for the 
  /// scope most closely enclosing the object, the object entry may have a 
  /// DW_AT_start_scope attribute.
  DenseMap<const MachineInstr *, DbgVariable *> DbgValueStartMap;

  /// InliendSubprogramDIEs - Collection of subprgram DIEs that are marked
  /// (at the end of the module) as DW_AT_inline.
  SmallPtrSet<DIE *, 4> InlinedSubprogramDIEs;

  /// 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 *, MDNode *> ContainingTypeMap;

  typedef SmallVector<DbgScope *, 2> ScopeVector;
  SmallPtrSet<const MachineInstr *, 8> InsnsBeginScopeSet;
  SmallPtrSet<const MachineInstr *, 8> InsnsEndScopeSet;

  /// InlineInfo - Keep track of inlined functions and their location.  This
  /// information is used to populate debug_inlined section.
  typedef std::pair<MCSymbol*, DIE *> InlineInfoLabels;
  DenseMap<MDNode*, SmallVector<InlineInfoLabels, 4> > InlineInfo;
  SmallVector<MDNode *, 4> InlinedSPNodes;

  /// InsnBeforeLabelMap - Maps instruction with label emitted before 
  /// instruction.
  DenseMap<const MachineInstr *, MCSymbol *> InsnBeforeLabelMap;

  /// InsnAfterLabelMap - Maps instruction with label emitted after
  /// instruction.
  DenseMap<const MachineInstr *, MCSymbol *> InsnAfterLabelMap;

  /// Previous instruction's location information. This is used to determine
  /// label location to indicate scope boundries in dwarf debug info.
  DebugLoc PrevInstLoc;

  struct FunctionDebugFrameInfo {
    unsigned Number;
    std::vector<MachineMove> Moves;

    FunctionDebugFrameInfo(unsigned Num, const std::vector<MachineMove> &M)
      : Number(Num), Moves(M) {}
  };

  std::vector<FunctionDebugFrameInfo> DebugFrames;

  // Section Symbols: these are assembler temporary labels that are emitted at
  // the beginning of each supported dwarf section.  These are used to form
  // section offsets and are created by EmitSectionLabels.
  MCSymbol *DwarfFrameSectionSym, *DwarfInfoSectionSym, *DwarfAbbrevSectionSym;
  MCSymbol *DwarfStrSectionSym, *TextSectionSym;
  
private:
  
  /// getSourceDirectoryAndFileIds - Return the directory and file ids that
  /// maps to the source id. Source id starts at 1.
  std::pair<unsigned, unsigned>
  getSourceDirectoryAndFileIds(unsigned SId) const {
    return SourceIds[SId-1];
  }

  /// getNumSourceDirectories - Return the number of source directories in the
  /// debug info.
  unsigned getNumSourceDirectories() const {
    return DirectoryNames.size();
  }

  /// getSourceDirectoryName - Return the name of the directory corresponding
  /// to the id.
  const std::string &getSourceDirectoryName(unsigned Id) const {
    return DirectoryNames[Id - 1];
  }

  /// getSourceFileName - Return the name of the source file corresponding
  /// to the id.
  const std::string &getSourceFileName(unsigned Id) const {
    return SourceFileNames[Id - 1];
  }

  /// getNumSourceIds - Return the number of unique source ids.
  unsigned getNumSourceIds() const {
    return SourceIds.size();
  }

  /// assignAbbrevNumber - Define a unique number for the abbreviation.
  ///
  void assignAbbrevNumber(DIEAbbrev &Abbrev);

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

  /// addUInt - Add an unsigned integer attribute data and value.
  ///
  void addUInt(DIE *Die, unsigned Attribute,