path: root/include/llvm/Analysis/DebugInfo.h

//===--- llvm/Analysis/DebugInfo.h - Debug Information Helpers --*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines a bunch of datatypes that are useful for creating and
// walking debug info in LLVM IR form. They essentially provide wrappers around
// the information in the global variables that's needed when constructing the
// DWARF information.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_ANALYSIS_DEBUGINFO_H
#define LLVM_ANALYSIS_DEBUGINFO_H

#include "llvm/Target/TargetMachine.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/Support/Dwarf.h"

namespace llvm {
  class BasicBlock;
  class Constant;
  class Function;
  class GlobalVariable;
  class Module;
  class Type;
  class Value;
  struct DbgStopPointInst;
  struct DbgDeclareInst;
  struct DbgFuncStartInst;
  struct DbgRegionStartInst;
  struct DbgRegionEndInst;
  class DebugLoc;
  struct DebugLocTracker;
  class Instruction;
  class LLVMContext;

  class DIDescriptor {
  protected:    
    GlobalVariable *DbgGV;

    /// DIDescriptor constructor.  If the specified GV is non-null, this checks
    /// to make sure that the tag in the descriptor matches 'RequiredTag'.  If
    /// not, the debug info is corrupt and we ignore it.
    DIDescriptor(GlobalVariable *GV, unsigned RequiredTag);

    const std::string &getStringField(unsigned Elt, std::string &Result) const;
    unsigned getUnsignedField(unsigned Elt) const {
      return (unsigned)getUInt64Field(Elt);
    }
    uint64_t getUInt64Field(unsigned Elt) const;
    DIDescriptor getDescriptorField(unsigned Elt) const;

    template <typename DescTy>
    DescTy getFieldAs(unsigned Elt) const {
      return DescTy(getDescriptorField(Elt).getGV());
    }

    GlobalVariable *getGlobalVariableField(unsigned Elt) const;

  public:
    explicit DIDescriptor() : DbgGV(0) {}
    explicit DIDescriptor(GlobalVariable *GV) : DbgGV(GV) {}

    bool isNull() const { return DbgGV == 0; }

    GlobalVariable *getGV() const { return DbgGV; }

    unsigned getVersion() const {
      return getUnsignedField(0) & LLVMDebugVersionMask;
    }

    unsigned getTag() const {
      return getUnsignedField(0) & ~LLVMDebugVersionMask;
    }

    /// ValidDebugInfo - Return true if V represents valid debug info value.
    static bool ValidDebugInfo(Value *V, CodeGenOpt::Level OptLevel);

    /// dump - print descriptor.
    void dump() const;
  };

  /// DISubrange - This is used to represent ranges, for array bounds.
  class DISubrange : public DIDescriptor {
  public:
    explicit DISubrange(GlobalVariable *GV = 0)
      : DIDescriptor(GV, dwarf::DW_TAG_subrange_type) {}

    int64_t getLo() const { return (int64_t)getUInt64Field(1); }
    int64_t getHi() const { return (int64_t)getUInt64Field(2); }
  };

  /// DIArray - This descriptor holds an array of descriptors.
  class DIArray : public DIDescriptor {
  public:
    explicit DIArray(GlobalVariable *GV = 0) : DIDescriptor(GV) {}

    unsigned getNumElements() const;
    DIDescriptor getElement(unsigned Idx) const {
      return getDescriptorField(Idx);
    }
  };

  /// DICompileUnit - A wrapper for a compile unit.
  class DICompileUnit : public DIDescriptor {
  public:
    explicit DICompileUnit(GlobalVariable *GV = 0)
      : DIDescriptor(GV, dwarf::DW_TAG_compile_unit) {}

    unsigned getLanguage() const     { return getUnsignedField(2); }
    const std::string &getFilename(std::string &F) const {
      return getStringField(3, F);
    }
    const std::string &getDirectory(std::string &F) const {
      return getStringField(4, F);
    }
    const std::string &getProducer(std::string &F) const {
      return getStringField(5, F);
    }
    
    /// isMain - Each input file is encoded as a separate compile unit in LLVM
    /// debugging information output. However, many target specific tool chains
    /// prefer to encode only one compile unit in an object file. In this 
    /// situation, the LLVM code generator will include  debugging information
    /// entities in the compile unit that is marked as main compile unit. The 
    /// code generator accepts maximum one main compile unit per module. If a
    /// module does not contain any main compile unit then the code generator 
    /// will emit multiple compile units in the output object file.

    bool isMain() const                { return getUnsignedField(6); }
    bool isOptimized() const           { return getUnsignedField(7); }
    const std::string &getFlags(std::string &F) const {
      return getStringField(8, F);
    }
    unsigned getRunTimeVersion() const { return getUnsignedField(9); }

    /// Verify - Verify that a compile unit is well formed.
    bool Verify() const;

    /// dump - print compile unit.
    void dump() const;
  };

  /// DIEnumerator - A wrapper for an enumerator (e.g. X and Y in 'enum {X,Y}').
  /// FIXME: it seems strange that this doesn't have either a reference to the
  /// type/precision or a file/line pair for location info.
  class DIEnumerator : public DIDescriptor {
  public:
    explicit DIEnumerator(GlobalVariable *GV = 0)
      : DIDescriptor(GV, dwarf::DW_TAG_enumerator) {}

    const std::string &getName(std::string &F) const {
      return getStringField(1, F);
    }
    uint64_t getEnumValue() const { return getUInt64Field(2); }
  };

  /// DIType - This is a wrapper for a type.
  /// FIXME: Types should be factored much better so that CV qualifiers and
  /// others do not require a huge and empty descriptor full of zeros.
  class DIType : public DIDescriptor {
  public:
    enum {
      FlagPrivate   = 1 << 0,
      FlagProtected = 1 << 1,
      FlagFwdDecl   = 1 << 2
    };

  protected:
    DIType(GlobalVariable *GV, unsigned Tag) : DIDescriptor(GV, Tag) {}
    // This ctor is used when the Tag has already been validated by a derived
    // ctor.
    DIType(GlobalVariable *GV, bool, bool) : DIDescriptor(GV) {}

  public:
    /// isDerivedType - Return true if the specified tag is legal for
    /// DIDerivedType.
    static bool isDerivedType(unsigned TAG);

    /// isCompositeType - Return true if the specified tag is legal for
    /// DICompositeType.
    static bool isCompositeType(unsigned TAG);

    /// isBasicType - Return true if the specified tag is legal for
    /// DIBasicType.
    static bool isBasicType(unsigned TAG) {
      return TAG == dwarf::DW_TAG_base_type;
    }

    /// Verify - Verify that a type descriptor is well formed.
    bool Verify() const;
  public:
    explicit DIType(GlobalVariable *GV);
    explicit DIType() {}
    virtual ~DIType() {}

    DIDescriptor getContext() const     { return getDescriptorField(1); }
    const std::string &getName(std::string &F) const {
      return getStringField(2, F);
    }
    DICompileUnit getCompileUnit() const{ return getFieldAs<DICompileUnit>(3); }