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      1 //===--- llvm/Analysis/DebugInfo.h - Debug Information Helpers --*- C++ -*-===//
      2 //
      3 //                     The LLVM Compiler Infrastructure
      4 //
      5 // This file is distributed under the University of Illinois Open Source
      6 // License. See LICENSE.TXT for details.
      7 //
      8 //===----------------------------------------------------------------------===//
      9 //
     10 // This file defines a bunch of datatypes that are useful for creating and
     11 // walking debug info in LLVM IR form. They essentially provide wrappers around
     12 // the information in the global variables that's needed when constructing the
     13 // DWARF information.
     14 //
     15 //===----------------------------------------------------------------------===//
     16 
     17 #ifndef LLVM_DEBUGINFO_H
     18 #define LLVM_DEBUGINFO_H
     19 
     20 #include "llvm/ADT/SmallPtrSet.h"
     21 #include "llvm/ADT/SmallVector.h"
     22 #include "llvm/ADT/StringRef.h"
     23 #include "llvm/Support/Dwarf.h"
     24 
     25 namespace llvm {
     26   class BasicBlock;
     27   class Constant;
     28   class Function;
     29   class GlobalVariable;
     30   class Module;
     31   class Type;
     32   class Value;
     33   class DbgDeclareInst;
     34   class DbgValueInst;
     35   class Instruction;
     36   class MDNode;
     37   class NamedMDNode;
     38   class LLVMContext;
     39   class raw_ostream;
     40 
     41   class DIFile;
     42   class DISubprogram;
     43   class DILexicalBlock;
     44   class DILexicalBlockFile;
     45   class DIVariable;
     46   class DIType;
     47   class DIObjCProperty;
     48 
     49   /// DIDescriptor - A thin wraper around MDNode to access encoded debug info.
     50   /// This should not be stored in a container, because the underlying MDNode
     51   /// may change in certain situations.
     52   class DIDescriptor {
     53   public:
     54     enum {
     55       FlagPrivate            = 1 << 0,
     56       FlagProtected          = 1 << 1,
     57       FlagFwdDecl            = 1 << 2,
     58       FlagAppleBlock         = 1 << 3,
     59       FlagBlockByrefStruct   = 1 << 4,
     60       FlagVirtual            = 1 << 5,
     61       FlagArtificial         = 1 << 6,
     62       FlagExplicit           = 1 << 7,
     63       FlagPrototyped         = 1 << 8,
     64       FlagObjcClassComplete  = 1 << 9,
     65       FlagObjectPointer      = 1 << 10,
     66       FlagVector             = 1 << 11,
     67       FlagStaticMember       = 1 << 12,
     68       FlagIndirectVariable   = 1 << 13
     69     };
     70   protected:
     71     const MDNode *DbgNode;
     72 
     73     StringRef getStringField(unsigned Elt) const;
     74     unsigned getUnsignedField(unsigned Elt) const {
     75       return (unsigned)getUInt64Field(Elt);
     76     }
     77     uint64_t getUInt64Field(unsigned Elt) const;
     78     int64_t getInt64Field(unsigned Elt) const;
     79     DIDescriptor getDescriptorField(unsigned Elt) const;
     80 
     81     template <typename DescTy>
     82     DescTy getFieldAs(unsigned Elt) const {
     83       return DescTy(getDescriptorField(Elt));
     84     }
     85 
     86     GlobalVariable *getGlobalVariableField(unsigned Elt) const;
     87     Constant *getConstantField(unsigned Elt) const;
     88     Function *getFunctionField(unsigned Elt) const;
     89     void replaceFunctionField(unsigned Elt, Function *F);
     90 
     91   public:
     92     explicit DIDescriptor(const MDNode *N = 0) : DbgNode(N) {}
     93 
     94     bool Verify() const;
     95 
     96     operator MDNode *() const { return const_cast<MDNode*>(DbgNode); }
     97     MDNode *operator ->() const { return const_cast<MDNode*>(DbgNode); }
     98 
     99     // An explicit operator bool so that we can do testing of DI values
    100     // easily.
    101     // FIXME: This operator bool isn't actually protecting anything at the
    102     // moment due to the conversion operator above making DIDescriptor nodes
    103     // implicitly convertable to bool.
    104     LLVM_EXPLICIT operator bool() const { return DbgNode != 0; }
    105 
    106     bool operator==(DIDescriptor Other) const {
    107       return DbgNode == Other.DbgNode;
    108     }
    109     bool operator!=(DIDescriptor Other) const {
    110       return !operator==(Other);
    111     }
    112 
    113     unsigned getTag() const {
    114       return getUnsignedField(0) & ~LLVMDebugVersionMask;
    115     }
    116 
    117     bool isDerivedType() const;
    118     bool isCompositeType() const;
    119     bool isBasicType() const;
    120     bool isVariable() const;
    121     bool isSubprogram() const;
    122     bool isGlobalVariable() const;
    123     bool isScope() const;
    124     bool isFile() const;
    125     bool isCompileUnit() const;
    126     bool isNameSpace() const;
    127     bool isLexicalBlockFile() const;
    128     bool isLexicalBlock() const;
    129     bool isSubrange() const;
    130     bool isEnumerator() const;
    131     bool isType() const;
    132     bool isUnspecifiedParameter() const;
    133     bool isTemplateTypeParameter() const;
    134     bool isTemplateValueParameter() const;
    135     bool isObjCProperty() const;
    136     bool isImportedEntity() const;
    137 
    138     /// print - print descriptor.
    139     void print(raw_ostream &OS) const;
    140 
    141     /// dump - print descriptor to dbgs() with a newline.
    142     void dump() const;
    143   };
    144 
    145   /// DISubrange - This is used to represent ranges, for array bounds.
    146   class DISubrange : public DIDescriptor {
    147     friend class DIDescriptor;
    148     void printInternal(raw_ostream &OS) const;
    149   public:
    150     explicit DISubrange(const MDNode *N = 0) : DIDescriptor(N) {}
    151 
    152     int64_t getLo() const { return getInt64Field(1); }
    153     int64_t  getCount() const { return getInt64Field(2); }
    154     bool Verify() const;
    155   };
    156 
    157   /// DIArray - This descriptor holds an array of descriptors.
    158   class DIArray : public DIDescriptor {
    159   public:
    160     explicit DIArray(const MDNode *N = 0) : DIDescriptor(N) {}
    161 
    162     unsigned getNumElements() const;
    163     DIDescriptor getElement(unsigned Idx) const {
    164       return getDescriptorField(Idx);
    165     }
    166   };
    167 
    168   /// DIEnumerator - A wrapper for an enumerator (e.g. X and Y in 'enum {X,Y}').
    169   /// FIXME: it seems strange that this doesn't have either a reference to the
    170   /// type/precision or a file/line pair for location info.
    171   class DIEnumerator : public DIDescriptor {
    172     friend class DIDescriptor;
    173     void printInternal(raw_ostream &OS) const;
    174   public:
    175     explicit DIEnumerator(const MDNode *N = 0) : DIDescriptor(N) {}
    176 
    177     StringRef getName() const        { return getStringField(1); }
    178     int64_t getEnumValue() const      { return getInt64Field(2); }
    179     bool Verify() const;
    180   };
    181 
    182   /// DIScope - A base class for various scopes.
    183   class DIScope : public DIDescriptor {
    184   protected:
    185     friend class DIDescriptor;
    186     void printInternal(raw_ostream &OS) const;
    187   public:
    188     explicit DIScope(const MDNode *N = 0) : DIDescriptor (N) {}
    189 
    190     /// Gets the parent scope for this scope node or returns a
    191     /// default constructed scope.
    192     DIScope getContext() const;
    193     StringRef getFilename() const;
    194     StringRef getDirectory() const;
    195   };
    196 
    197   /// DIType - This is a wrapper for a type.
    198   /// FIXME: Types should be factored much better so that CV qualifiers and
    199   /// others do not require a huge and empty descriptor full of zeros.
    200   class DIType : public DIScope {
    201   protected:
    202     friend class DIDescriptor;
    203     void printInternal(raw_ostream &OS) const;
    204 
    205   public:
    206     DIType(const MDNode *N = 0) : DIScope(N) {}
    207 
    208     /// Verify - Verify that a type descriptor is well formed.
    209     bool Verify() const;
    210 
    211     DIScope getContext() const          { return getFieldAs<DIScope>(2); }
    212     StringRef getName() const           { return getStringField(3);     }
    213     unsigned getLineNumber() const      { return getUnsignedField(4); }
    214     uint64_t getSizeInBits() const      { return getUInt64Field(5); }
    215     uint64_t getAlignInBits() const     { return getUInt64Field(6); }
    216     // FIXME: Offset is only used for DW_TAG_member nodes.  Making every type
    217     // carry this is just plain insane.
    218     uint64_t getOffsetInBits() const    { return getUInt64Field(7); }
    219     unsigned getFlags() const           { return getUnsignedField(8); }
    220     bool isPrivate() const {
    221       return (getFlags() & FlagPrivate) != 0;
    222     }
    223     bool isProtected() const {
    224       return (getFlags() & FlagProtected) != 0;
    225     }
    226     bool isForwardDecl() const {
    227       return (getFlags() & FlagFwdDecl) != 0;
    228     }
    229     // isAppleBlock - Return true if this is the Apple Blocks extension.
    230     bool isAppleBlockExtension() const {
    231       return (getFlags() & FlagAppleBlock) != 0;
    232     }
    233     bool isBlockByrefStruct() const {
    234       return (getFlags() & FlagBlockByrefStruct) != 0;
    235     }
    236     bool isVirtual() const {
    237       return (getFlags() & FlagVirtual) != 0;
    238     }
    239     bool isArtificial() const {
    240       return (getFlags() & FlagArtificial) != 0;
    241     }
    242     bool isObjectPointer() const {
    243       return (getFlags() & FlagObjectPointer) != 0;
    244     }
    245     bool isObjcClassComplete() const {
    246       return (getFlags() & FlagObjcClassComplete) != 0;
    247     }
    248     bool isVector() const {
    249       return (getFlags() & FlagVector) != 0;
    250     }
    251     bool isStaticMember() const {
    252       return (getFlags() & FlagStaticMember) != 0;
    253     }
    254     bool isValid() const {
    255       return DbgNode && isType();
    256     }
    257 
    258     /// isUnsignedDIType - Return true if type encoding is unsigned.
    259     bool isUnsignedDIType();
    260 
    261     /// replaceAllUsesWith - Replace all uses of debug info referenced by
    262     /// this descriptor.
    263     void replaceAllUsesWith(DIDescriptor &D);
    264     void replaceAllUsesWith(MDNode *D);
    265   };
    266 
    267   /// DIBasicType - A basic type, like 'int' or 'float'.
    268   class DIBasicType : public DIType {
    269   public:
    270     explicit DIBasicType(const MDNode *N = 0) : DIType(N) {}
    271 
    272     unsigned getEncoding() const { return getUnsignedField(9); }
    273 
    274     /// Verify - Verify that a basic type descriptor is well formed.
    275     bool Verify() const;
    276   };
    277 
    278   /// DIDerivedType - A simple derived type, like a const qualified type,
    279   /// a typedef, a pointer or reference, et cetera.  Or, a data member of
    280   /// a class/struct/union.
    281   class DIDerivedType : public DIType {
    282     friend class DIDescriptor;
    283     void printInternal(raw_ostream &OS) const;
    284 
    285   public:
    286     explicit DIDerivedType(const MDNode *N = 0) : DIType(N) {}
    287 
    288     DIType getTypeDerivedFrom() const { return getFieldAs<DIType>(9); }
    289 
    290     /// getOriginalTypeSize - If this type is derived from a base type then
    291     /// return base type size.
    292     uint64_t getOriginalTypeSize() const;
    293 
    294     /// getObjCProperty - Return property node, if this ivar is
    295     /// associated with one.
    296     MDNode *getObjCProperty() const;
    297 
    298     DIType getClassType() const {
    299       assert(getTag() == dwarf::DW_TAG_ptr_to_member_type);
    300       return getFieldAs<DIType>(10);
    301     }
    302 
    303     Constant *getConstant() const {
    304       assert((getTag() == dwarf::DW_TAG_member) && isStaticMember());
    305       return getConstantField(10);
    306     }
    307 
    308     /// Verify - Verify that a derived type descriptor is well formed.
    309     bool Verify() const;
    310   };
    311 
    312   /// DICompositeType - This descriptor holds a type that can refer to multiple
    313   /// other types, like a function or struct.
    314   /// DICompositeType is derived from DIDerivedType because some
    315   /// composite types (such as enums) can be derived from basic types
    316   // FIXME: Make this derive from DIType directly & just store the
    317   // base type in a single DIType field.
    318   class DICompositeType : public DIDerivedType {
    319     friend class DIDescriptor;
    320     void printInternal(raw_ostream &OS) const;
    321   public:
    322     explicit DICompositeType(const MDNode *N = 0) : DIDerivedType(N) {}
    323 
    324     DIArray getTypeArray() const { return getFieldAs<DIArray>(10); }
    325     void setTypeArray(DIArray Elements, DIArray TParams = DIArray());
    326     unsigned getRunTimeLang() const { return getUnsignedField(11); }
    327     DICompositeType getContainingType() const {
    328       return getFieldAs<DICompositeType>(12);
    329     }
    330     void setContainingType(DICompositeType ContainingType);
    331     DIArray getTemplateParams() const { return getFieldAs<DIArray>(13); }
    332 
    333     /// Verify - Verify that a composite type descriptor is well formed.
    334     bool Verify() const;
    335   };
    336 
    337   /// DIFile - This is a wrapper for a file.
    338   class DIFile : public DIScope {
    339     friend class DIDescriptor;
    340   public:
    341     explicit DIFile(const MDNode *N = 0) : DIScope(N) {}
    342     MDNode *getFileNode() const;
    343     bool Verify() const;
    344   };
    345 
    346   /// DICompileUnit - A wrapper for a compile unit.
    347   class DICompileUnit : public DIScope {
    348     friend class DIDescriptor;
    349     void printInternal(raw_ostream &OS) const;
    350   public:
    351     explicit DICompileUnit(const MDNode *N = 0) : DIScope(N) {}
    352 
    353     unsigned getLanguage() const { return getUnsignedField(2); }
    354     StringRef getProducer() const { return getStringField(3); }
    355 
    356     bool isOptimized() const { return getUnsignedField(4) != 0; }
    357     StringRef getFlags() const { return getStringField(5); }
    358     unsigned getRunTimeVersion() const { return getUnsignedField(6); }
    359 
    360     DIArray getEnumTypes() const;
    361     DIArray getRetainedTypes() const;
    362     DIArray getSubprograms() const;
    363     DIArray getGlobalVariables() const;
    364     DIArray getImportedEntities() const;
    365 
    366     StringRef getSplitDebugFilename() const { return getStringField(12); }
    367 
    368     /// Verify - Verify that a compile unit is well formed.
    369     bool Verify() const;
    370   };
    371 
    372   /// DISubprogram - This is a wrapper for a subprogram (e.g. a function).
    373   class DISubprogram : public DIScope {
    374     friend class DIDescriptor;
    375     void printInternal(raw_ostream &OS) const;
    376   public:
    377     explicit DISubprogram(const MDNode *N = 0) : DIScope(N) {}
    378 
    379     DIScope getContext() const          { return getFieldAs<DIScope>(2); }
    380     StringRef getName() const         { return getStringField(3); }
    381     StringRef getDisplayName() const  { return getStringField(4); }
    382     StringRef getLinkageName() const  { return getStringField(5); }
    383     unsigned getLineNumber() const      { return getUnsignedField(6); }
    384     DICompositeType getType() const { return getFieldAs<DICompositeType>(7); }
    385 
    386     /// isLocalToUnit - Return true if this subprogram is local to the current
    387     /// compile unit, like 'static' in C.
    388     unsigned isLocalToUnit() const     { return getUnsignedField(8); }
    389     unsigned isDefinition() const      { return getUnsignedField(9); }
    390 
    391     unsigned getVirtuality() const { return getUnsignedField(10); }
    392     unsigned getVirtualIndex() const { return getUnsignedField(11); }
    393 
    394     DICompositeType getContainingType() const {
    395       return getFieldAs<DICompositeType>(12);
    396     }
    397 
    398     unsigned getFlags() const {
    399       return getUnsignedField(13);
    400     }
    401 
    402     unsigned isArtificial() const    {
    403       return (getUnsignedField(13) & FlagArtificial) != 0;
    404     }
    405     /// isPrivate - Return true if this subprogram has "private"
    406     /// access specifier.
    407     bool isPrivate() const    {
    408       return (getUnsignedField(13) & FlagPrivate) != 0;
    409     }
    410     /// isProtected - Return true if this subprogram has "protected"
    411     /// access specifier.
    412     bool isProtected() const    {
    413       return (getUnsignedField(13) & FlagProtected) != 0;
    414     }
    415     /// isExplicit - Return true if this subprogram is marked as explicit.
    416     bool isExplicit() const    {
    417       return (getUnsignedField(13) & FlagExplicit) != 0;
    418     }
    419     /// isPrototyped - Return true if this subprogram is prototyped.
    420     bool isPrototyped() const    {
    421       return (getUnsignedField(13) & FlagPrototyped) != 0;
    422     }
    423 
    424     unsigned isOptimized() const;
    425 
    426     /// Verify - Verify that a subprogram descriptor is well formed.
    427     bool Verify() const;
    428 
    429     /// describes - Return true if this subprogram provides debugging
    430     /// information for the function F.
    431     bool describes(const Function *F);
    432 
    433     Function *getFunction() const { return getFunctionField(15); }
    434     void replaceFunction(Function *F) { replaceFunctionField(15, F); }
    435     DIArray getTemplateParams() const { return getFieldAs<DIArray>(16); }
    436     DISubprogram getFunctionDeclaration() const {
    437       return getFieldAs<DISubprogram>(17);
    438     }
    439     MDNode *getVariablesNodes() const;
    440     DIArray getVariables() const;
    441 
    442     /// getScopeLineNumber - Get the beginning of the scope of the
    443     /// function, not necessarily where the name of the program
    444     /// starts.
    445     unsigned getScopeLineNumber() const { return getUnsignedField(19); }
    446   };
    447 
    448   /// DILexicalBlock - This is a wrapper for a lexical block.
    449   class DILexicalBlock : public DIScope {
    450   public:
    451     explicit DILexicalBlock(const MDNode *N = 0) : DIScope(N) {}
    452     DIScope getContext() const       { return getFieldAs<DIScope>(2);      }
    453     unsigned getLineNumber() const   { return getUnsignedField(3);         }
    454     unsigned getColumnNumber() const { return getUnsignedField(4);         }
    455     bool Verify() const;
    456   };
    457 
    458   /// DILexicalBlockFile - This is a wrapper for a lexical block with
    459   /// a filename change.
    460   class DILexicalBlockFile : public DIScope {
    461   public:
    462     explicit DILexicalBlockFile(const MDNode *N = 0) : DIScope(N) {}
    463     DIScope getContext() const {
    464       if (getScope().isSubprogram())
    465         return getScope();
    466       return getScope().getContext();
    467     }
    468     unsigned getLineNumber() const { return getScope().getLineNumber(); }
    469     unsigned getColumnNumber() const { return getScope().getColumnNumber(); }
    470     DILexicalBlock getScope() const { return getFieldAs<DILexicalBlock>(2); }
    471     bool Verify() const;
    472   };
    473 
    474   /// DINameSpace - A wrapper for a C++ style name space.
    475   class DINameSpace : public DIScope {
    476     friend class DIDescriptor;
    477     void printInternal(raw_ostream &OS) const;
    478   public:
    479     explicit DINameSpace(const MDNode *N = 0) : DIScope(N) {}
    480     DIScope getContext() const     { return getFieldAs<DIScope>(2);      }
    481     StringRef getName() const      { return getStringField(3);           }
    482     unsigned getLineNumber() const { return getUnsignedField(4);         }
    483     bool Verify() const;
    484   };
    485 
    486   /// DITemplateTypeParameter - This is a wrapper for template type parameter.
    487   class DITemplateTypeParameter : public DIDescriptor {
    488   public:
    489     explicit DITemplateTypeParameter(const MDNode *N = 0) : DIDescriptor(N) {}
    490 
    491     DIScope getContext() const       { return getFieldAs<DIScope>(1); }
    492     StringRef getName() const        { return getStringField(2); }
    493     DIType getType() const           { return getFieldAs<DIType>(3); }
    494     StringRef getFilename() const    {
    495       return getFieldAs<DIFile>(4).getFilename();
    496     }
    497     StringRef getDirectory() const   {
    498       return getFieldAs<DIFile>(4).getDirectory();
    499     }
    500     unsigned getLineNumber() const   { return getUnsignedField(5); }
    501     unsigned getColumnNumber() const { return getUnsignedField(6); }
    502     bool Verify() const;
    503   };
    504 
    505   /// DITemplateValueParameter - This is a wrapper for template value parameter.
    506   class DITemplateValueParameter : public DIDescriptor {
    507   public:
    508     explicit DITemplateValueParameter(const MDNode *N = 0) : DIDescriptor(N) {}
    509 
    510     DIScope getContext() const       { return getFieldAs<DIScope>(1); }
    511     StringRef getName() const        { return getStringField(2); }
    512     DIType getType() const           { return getFieldAs<DIType>(3); }
    513     Value *getValue() const;
    514     StringRef getFilename() const    {
    515       return getFieldAs<DIFile>(5).getFilename();
    516     }
    517     StringRef getDirectory() const   {
    518       return getFieldAs<DIFile>(5).getDirectory();
    519     }
    520     unsigned getLineNumber() const   { return getUnsignedField(6); }
    521     unsigned getColumnNumber() const { return getUnsignedField(7); }
    522     bool Verify() const;
    523   };
    524 
    525   /// DIGlobalVariable - This is a wrapper for a global variable.
    526   class DIGlobalVariable : public DIDescriptor {
    527     friend class DIDescriptor;
    528     void printInternal(raw_ostream &OS) const;
    529   public:
    530     explicit DIGlobalVariable(const MDNode *N = 0) : DIDescriptor(N) {}
    531 
    532     DIScope getContext() const          { return getFieldAs<DIScope>(2); }
    533     StringRef getName() const         { return getStringField(3); }
    534     StringRef getDisplayName() const  { return getStringField(4); }
    535     StringRef getLinkageName() const  { return getStringField(5); }
    536     StringRef getFilename() const {
    537       return getFieldAs<DIFile>(6).getFilename();
    538     }
    539     StringRef getDirectory() const {
    540       return getFieldAs<DIFile>(6).getDirectory();
    541 
    542     }
    543 
    544     unsigned getLineNumber() const      { return getUnsignedField(7); }
    545     DIType getType() const              { return getFieldAs<DIType>(8); }
    546     unsigned isLocalToUnit() const      { return getUnsignedField(9); }
    547     unsigned isDefinition() const       { return getUnsignedField(10); }
    548 
    549     GlobalVariable *getGlobal() const { return getGlobalVariableField(11); }
    550     Constant *getConstant() const   { return getConstantField(11); }
    551     DIDerivedType getStaticDataMemberDeclaration() const {
    552       return getFieldAs<DIDerivedType>(12);
    553     }
    554 
    555     /// Verify - Verify that a global variable descriptor is well formed.
    556     bool Verify() const;
    557   };
    558 
    559   /// DIVariable - This is a wrapper for a variable (e.g. parameter, local,
    560   /// global etc).
    561   class DIVariable : public DIDescriptor {
    562     friend class DIDescriptor;
    563     void printInternal(raw_ostream &OS) const;
    564   public:
    565     explicit DIVariable(const MDNode *N = 0) : DIDescriptor(N) {}
    566 
    567     DIScope getContext() const          { return getFieldAs<DIScope>(1); }
    568     StringRef getName() const           { return getStringField(2);     }
    569     DIFile getFile() const              { return getFieldAs<DIFile>(3); }
    570     unsigned getLineNumber() const      {
    571       return (getUnsignedField(4) << 8) >> 8;
    572     }
    573     unsigned getArgNumber() const       {
    574       unsigned L = getUnsignedField(4);
    575       return L >> 24;
    576     }
    577     DIType getType() const              { return getFieldAs<DIType>(5); }
    578 
    579     /// isArtificial - Return true if this variable is marked as "artificial".
    580     bool isArtificial() const    {
    581       return (getUnsignedField(6) & FlagArtificial) != 0;
    582     }
    583 
    584     bool isObjectPointer() const {
    585       return (getUnsignedField(6) & FlagObjectPointer) != 0;
    586     }
    587 
    588     /// \brief Return true if this variable is represented as a pointer.
    589     bool isIndirect() const {
    590       return (getUnsignedField(6) & FlagIndirectVariable) != 0;
    591     }
    592 
    593     /// getInlinedAt - If this variable is inlined then return inline location.
    594     MDNode *getInlinedAt() const;
    595 
    596     /// Verify - Verify that a variable descriptor is well formed.
    597     bool Verify() const;
    598 
    599     /// HasComplexAddr - Return true if the variable has a complex address.
    600     bool hasComplexAddress() const {
    601       return getNumAddrElements() > 0;
    602     }
    603 
    604     unsigned getNumAddrElements() const;
    605 
    606     uint64_t getAddrElement(unsigned Idx) const {
    607       return getUInt64Field(Idx+8);
    608     }
    609 
    610     /// isBlockByrefVariable - Return true if the variable was declared as
    611     /// a "__block" variable (Apple Blocks).
    612     bool isBlockByrefVariable() const {
    613       return getType().isBlockByrefStruct();
    614     }
    615 
    616     /// isInlinedFnArgument - Return true if this variable provides debugging
    617     /// information for an inlined function arguments.
    618     bool isInlinedFnArgument(const Function *CurFn);
    619 
    620     void printExtendedName(raw_ostream &OS) const;
    621   };
    622 
    623   /// DILocation - This object holds location information. This object
    624   /// is not associated with any DWARF tag.
    625   class DILocation : public DIDescriptor {
    626   public:
    627     explicit DILocation(const MDNode *N) : DIDescriptor(N) { }
    628 
    629     unsigned getLineNumber() const     { return getUnsignedField(0); }
    630     unsigned getColumnNumber() const   { return getUnsignedField(1); }
    631     DIScope  getScope() const          { return getFieldAs<DIScope>(2); }
    632     DILocation getOrigLocation() const { return getFieldAs<DILocation>(3); }
    633     StringRef getFilename() const    { return getScope().getFilename(); }
    634     StringRef getDirectory() const   { return getScope().getDirectory(); }
    635     bool Verify() const;
    636   };
    637 
    638   class DIObjCProperty : public DIDescriptor {
    639     friend class DIDescriptor;
    640     void printInternal(raw_ostream &OS) const;
    641   public:
    642     explicit DIObjCProperty(const MDNode *N) : DIDescriptor(N) { }
    643 
    644     StringRef getObjCPropertyName() const { return getStringField(1); }
    645     DIFile getFile() const { return getFieldAs<DIFile>(2); }
    646     unsigned getLineNumber() const { return getUnsignedField(3); }
    647 
    648     StringRef getObjCPropertyGetterName() const {
    649       return getStringField(4);
    650     }
    651     StringRef getObjCPropertySetterName() const {
    652       return getStringField(5);
    653     }
    654     bool isReadOnlyObjCProperty() const {
    655       return (getUnsignedField(6) & dwarf::DW_APPLE_PROPERTY_readonly) != 0;
    656     }
    657     bool isReadWriteObjCProperty() const {
    658       return (getUnsignedField(6) & dwarf::DW_APPLE_PROPERTY_readwrite) != 0;
    659     }
    660     bool isAssignObjCProperty() const {
    661       return (getUnsignedField(6) & dwarf::DW_APPLE_PROPERTY_assign) != 0;
    662     }
    663     bool isRetainObjCProperty() const {
    664       return (getUnsignedField(6) & dwarf::DW_APPLE_PROPERTY_retain) != 0;
    665     }
    666     bool isCopyObjCProperty() const {
    667       return (getUnsignedField(6) & dwarf::DW_APPLE_PROPERTY_copy) != 0;
    668     }
    669     bool isNonAtomicObjCProperty() const {
    670       return (getUnsignedField(6) & dwarf::DW_APPLE_PROPERTY_nonatomic) != 0;
    671     }
    672 
    673     DIType getType() const { return getFieldAs<DIType>(7); }
    674 
    675     /// Verify - Verify that a derived type descriptor is well formed.
    676     bool Verify() const;
    677   };
    678 
    679   /// \brief An imported module (C++ using directive or similar).
    680   class DIImportedEntity : public DIDescriptor {
    681     friend class DIDescriptor;
    682     void printInternal(raw_ostream &OS) const;
    683   public:
    684     explicit DIImportedEntity(const MDNode *N) : DIDescriptor(N) { }
    685     DIScope getContext() const { return getFieldAs<DIScope>(1); }
    686     DIDescriptor getEntity() const { return getFieldAs<DIDescriptor>(2); }
    687     unsigned getLineNumber() const { return getUnsignedField(3); }
    688     StringRef getName() const { return getStringField(4); }
    689     bool Verify() const;
    690   };
    691 
    692   /// getDISubprogram - Find subprogram that is enclosing this scope.
    693   DISubprogram getDISubprogram(const MDNode *Scope);
    694 
    695   /// getDICompositeType - Find underlying composite type.
    696   DICompositeType getDICompositeType(DIType T);
    697 
    698   /// isSubprogramContext - Return true if Context is either a subprogram
    699   /// or another context nested inside a subprogram.
    700   bool isSubprogramContext(const MDNode *Context);
    701 
    702   /// getOrInsertFnSpecificMDNode - Return a NameMDNode that is suitable
    703   /// to hold function specific information.
    704   NamedMDNode *getOrInsertFnSpecificMDNode(Module &M, DISubprogram SP);
    705 
    706   /// getFnSpecificMDNode - Return a NameMDNode, if available, that is
    707   /// suitable to hold function specific information.
    708   NamedMDNode *getFnSpecificMDNode(const Module &M, DISubprogram SP);
    709 
    710   /// createInlinedVariable - Create a new inlined variable based on current
    711   /// variable.
    712   /// @param DV            Current Variable.
    713   /// @param InlinedScope  Location at current variable is inlined.
    714   DIVariable createInlinedVariable(MDNode *DV, MDNode *InlinedScope,
    715                                    LLVMContext &VMContext);
    716 
    717   /// cleanseInlinedVariable - Remove inlined scope from the variable.
    718   DIVariable cleanseInlinedVariable(MDNode *DV, LLVMContext &VMContext);
    719 
    720   /// DebugInfoFinder tries to list all debug info MDNodes used in a module. To
    721   /// list debug info MDNodes used by an instruction, DebugInfoFinder uses
    722   /// processDeclare, processValue and processLocation to handle DbgDeclareInst,
    723   /// DbgValueInst and DbgLoc attached to instructions. processModule will go
    724   /// through all DICompileUnits in llvm.dbg.cu and list debug info MDNodes
    725   /// used by the CUs.
    726   class DebugInfoFinder {
    727   public:
    728     /// processModule - Process entire module and collect debug info
    729     /// anchors.
    730     void processModule(const Module &M);
    731 
    732     /// processDeclare - Process DbgDeclareInst.
    733     void processDeclare(const DbgDeclareInst *DDI);
    734     /// Process DbgValueInst.
    735     void processValue(const DbgValueInst *DVI);
    736     /// processLocation - Process DILocation.
    737     void processLocation(DILocation Loc);
    738 
    739     /// Clear all lists.
    740     void reset();
    741   private:
    742     /// processType - Process DIType.
    743     void processType(DIType DT);
    744 
    745     /// processLexicalBlock - Process DILexicalBlock.
    746     void processLexicalBlock(DILexicalBlock LB);
    747 
    748     /// processSubprogram - Process DISubprogram.
    749     void processSubprogram(DISubprogram SP);
    750 
    751     void processScope(DIScope Scope);
    752 
    753     /// addCompileUnit - Add compile unit into CUs.
    754     bool addCompileUnit(DICompileUnit CU);
    755 
    756     /// addGlobalVariable - Add global variable into GVs.
    757     bool addGlobalVariable(DIGlobalVariable DIG);
    758 
    759     // addSubprogram - Add subprogram into SPs.
    760     bool addSubprogram(DISubprogram SP);
    761 
    762     /// addType - Add type into Tys.
    763     bool addType(DIType DT);
    764 
    765     bool addScope(DIScope Scope);
    766 
    767   public:
    768     typedef SmallVectorImpl<MDNode *>::const_iterator iterator;
    769     iterator compile_unit_begin()    const { return CUs.begin(); }
    770     iterator compile_unit_end()      const { return CUs.end(); }
    771     iterator subprogram_begin()      const { return SPs.begin(); }
    772     iterator subprogram_end()        const { return SPs.end(); }
    773     iterator global_variable_begin() const { return GVs.begin(); }
    774     iterator global_variable_end()   const { return GVs.end(); }
    775     iterator type_begin()            const { return TYs.begin(); }
    776     iterator type_end()              const { return TYs.end(); }
    777     iterator scope_begin()           const { return Scopes.begin(); }
    778     iterator scope_end()             const { return Scopes.end(); }
    779 
    780     unsigned compile_unit_count()    const { return CUs.size(); }
    781     unsigned global_variable_count() const { return GVs.size(); }
    782     unsigned subprogram_count()      const { return SPs.size(); }
    783     unsigned type_count()            const { return TYs.size(); }
    784     unsigned scope_count()           const { return Scopes.size(); }
    785 
    786   private:
    787     SmallVector<MDNode *, 8> CUs;  // Compile Units
    788     SmallVector<MDNode *, 8> SPs;  // Subprograms
    789     SmallVector<MDNode *, 8> GVs;  // Global Variables;
    790     SmallVector<MDNode *, 8> TYs;  // Types
    791     SmallVector<MDNode *, 8> Scopes; // Scopes
    792     SmallPtrSet<MDNode *, 64> NodesSeen;
    793   };
    794 } // end namespace llvm
    795 
    796 #endif
    797