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      1 //===--- APValue.cpp - Union class for APFloat/APSInt/Complex -------------===//
      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 implements the APValue class.
     11 //
     12 //===----------------------------------------------------------------------===//
     13 
     14 #include "clang/AST/APValue.h"
     15 #include "clang/AST/ASTContext.h"
     16 #include "clang/AST/CharUnits.h"
     17 #include "clang/AST/DeclCXX.h"
     18 #include "clang/AST/Expr.h"
     19 #include "clang/AST/Type.h"
     20 #include "clang/Basic/Diagnostic.h"
     21 #include "llvm/ADT/SmallString.h"
     22 #include "llvm/Support/ErrorHandling.h"
     23 #include "llvm/Support/raw_ostream.h"
     24 using namespace clang;
     25 
     26 namespace {
     27   struct LVBase {
     28     llvm::PointerIntPair<APValue::LValueBase, 1, bool> BaseAndIsOnePastTheEnd;
     29     CharUnits Offset;
     30     unsigned PathLength;
     31     unsigned CallIndex;
     32   };
     33 }
     34 
     35 struct APValue::LV : LVBase {
     36   static const unsigned InlinePathSpace =
     37       (MaxSize - sizeof(LVBase)) / sizeof(LValuePathEntry);
     38 
     39   /// Path - The sequence of base classes, fields and array indices to follow to
     40   /// walk from Base to the subobject. When performing GCC-style folding, there
     41   /// may not be such a path.
     42   union {
     43     LValuePathEntry Path[InlinePathSpace];
     44     LValuePathEntry *PathPtr;
     45   };
     46 
     47   LV() { PathLength = (unsigned)-1; }
     48   ~LV() { resizePath(0); }
     49 
     50   void resizePath(unsigned Length) {
     51     if (Length == PathLength)
     52       return;
     53     if (hasPathPtr())
     54       delete [] PathPtr;
     55     PathLength = Length;
     56     if (hasPathPtr())
     57       PathPtr = new LValuePathEntry[Length];
     58   }
     59 
     60   bool hasPath() const { return PathLength != (unsigned)-1; }
     61   bool hasPathPtr() const { return hasPath() && PathLength > InlinePathSpace; }
     62 
     63   LValuePathEntry *getPath() { return hasPathPtr() ? PathPtr : Path; }
     64   const LValuePathEntry *getPath() const {
     65     return hasPathPtr() ? PathPtr : Path;
     66   }
     67 };
     68 
     69 namespace {
     70   struct MemberPointerBase {
     71     llvm::PointerIntPair<const ValueDecl*, 1, bool> MemberAndIsDerivedMember;
     72     unsigned PathLength;
     73   };
     74 }
     75 
     76 struct APValue::MemberPointerData : MemberPointerBase {
     77   static const unsigned InlinePathSpace =
     78       (MaxSize - sizeof(MemberPointerBase)) / sizeof(const CXXRecordDecl*);
     79   typedef const CXXRecordDecl *PathElem;
     80   union {
     81     PathElem Path[InlinePathSpace];
     82     PathElem *PathPtr;
     83   };
     84 
     85   MemberPointerData() { PathLength = 0; }
     86   ~MemberPointerData() { resizePath(0); }
     87 
     88   void resizePath(unsigned Length) {
     89     if (Length == PathLength)
     90       return;
     91     if (hasPathPtr())
     92       delete [] PathPtr;
     93     PathLength = Length;
     94     if (hasPathPtr())
     95       PathPtr = new PathElem[Length];
     96   }
     97 
     98   bool hasPathPtr() const { return PathLength > InlinePathSpace; }
     99 
    100   PathElem *getPath() { return hasPathPtr() ? PathPtr : Path; }
    101   const PathElem *getPath() const {
    102     return hasPathPtr() ? PathPtr : Path;
    103   }
    104 };
    105 
    106 // FIXME: Reduce the malloc traffic here.
    107 
    108 APValue::Arr::Arr(unsigned NumElts, unsigned Size) :
    109   Elts(new APValue[NumElts + (NumElts != Size ? 1 : 0)]),
    110   NumElts(NumElts), ArrSize(Size) {}
    111 APValue::Arr::~Arr() { delete [] Elts; }
    112 
    113 APValue::StructData::StructData(unsigned NumBases, unsigned NumFields) :
    114   Elts(new APValue[NumBases+NumFields]),
    115   NumBases(NumBases), NumFields(NumFields) {}
    116 APValue::StructData::~StructData() {
    117   delete [] Elts;
    118 }
    119 
    120 APValue::UnionData::UnionData() : Field(0), Value(new APValue) {}
    121 APValue::UnionData::~UnionData () {
    122   delete Value;
    123 }
    124 
    125 APValue::APValue(const APValue &RHS) : Kind(Uninitialized) {
    126   switch (RHS.getKind()) {
    127   case Uninitialized:
    128     break;
    129   case Int:
    130     MakeInt();
    131     setInt(RHS.getInt());
    132     break;
    133   case Float:
    134     MakeFloat();
    135     setFloat(RHS.getFloat());
    136     break;
    137   case Vector:
    138     MakeVector();
    139     setVector(((const Vec *)(const char *)RHS.Data)->Elts,
    140               RHS.getVectorLength());
    141     break;
    142   case ComplexInt:
    143     MakeComplexInt();
    144     setComplexInt(RHS.getComplexIntReal(), RHS.getComplexIntImag());
    145     break;
    146   case ComplexFloat:
    147     MakeComplexFloat();
    148     setComplexFloat(RHS.getComplexFloatReal(), RHS.getComplexFloatImag());
    149     break;
    150   case LValue:
    151     MakeLValue();
    152     if (RHS.hasLValuePath())
    153       setLValue(RHS.getLValueBase(), RHS.getLValueOffset(), RHS.getLValuePath(),
    154                 RHS.isLValueOnePastTheEnd(), RHS.getLValueCallIndex());
    155     else
    156       setLValue(RHS.getLValueBase(), RHS.getLValueOffset(), NoLValuePath(),
    157                 RHS.getLValueCallIndex());
    158     break;
    159   case Array:
    160     MakeArray(RHS.getArrayInitializedElts(), RHS.getArraySize());
    161     for (unsigned I = 0, N = RHS.getArrayInitializedElts(); I != N; ++I)
    162       getArrayInitializedElt(I) = RHS.getArrayInitializedElt(I);
    163     if (RHS.hasArrayFiller())
    164       getArrayFiller() = RHS.getArrayFiller();
    165     break;
    166   case Struct:
    167     MakeStruct(RHS.getStructNumBases(), RHS.getStructNumFields());
    168     for (unsigned I = 0, N = RHS.getStructNumBases(); I != N; ++I)
    169       getStructBase(I) = RHS.getStructBase(I);
    170     for (unsigned I = 0, N = RHS.getStructNumFields(); I != N; ++I)
    171       getStructField(I) = RHS.getStructField(I);
    172     break;
    173   case Union:
    174     MakeUnion();
    175     setUnion(RHS.getUnionField(), RHS.getUnionValue());
    176     break;
    177   case MemberPointer:
    178     MakeMemberPointer(RHS.getMemberPointerDecl(),
    179                       RHS.isMemberPointerToDerivedMember(),
    180                       RHS.getMemberPointerPath());
    181     break;
    182   case AddrLabelDiff:
    183     MakeAddrLabelDiff();
    184     setAddrLabelDiff(RHS.getAddrLabelDiffLHS(), RHS.getAddrLabelDiffRHS());
    185     break;
    186   }
    187 }
    188 
    189 void APValue::DestroyDataAndMakeUninit() {
    190   if (Kind == Int)
    191     ((APSInt*)(char*)Data)->~APSInt();
    192   else if (Kind == Float)
    193     ((APFloat*)(char*)Data)->~APFloat();
    194   else if (Kind == Vector)
    195     ((Vec*)(char*)Data)->~Vec();
    196   else if (Kind == ComplexInt)
    197     ((ComplexAPSInt*)(char*)Data)->~ComplexAPSInt();
    198   else if (Kind == ComplexFloat)
    199     ((ComplexAPFloat*)(char*)Data)->~ComplexAPFloat();
    200   else if (Kind == LValue)
    201     ((LV*)(char*)Data)->~LV();
    202   else if (Kind == Array)
    203     ((Arr*)(char*)Data)->~Arr();
    204   else if (Kind == Struct)
    205     ((StructData*)(char*)Data)->~StructData();
    206   else if (Kind == Union)
    207     ((UnionData*)(char*)Data)->~UnionData();
    208   else if (Kind == MemberPointer)
    209     ((MemberPointerData*)(char*)Data)->~MemberPointerData();
    210   else if (Kind == AddrLabelDiff)
    211     ((AddrLabelDiffData*)(char*)Data)->~AddrLabelDiffData();
    212   Kind = Uninitialized;
    213 }
    214 
    215 bool APValue::needsCleanup() const {
    216   switch (getKind()) {
    217   case Uninitialized:
    218   case AddrLabelDiff:
    219     return false;
    220   case Struct:
    221   case Union:
    222   case Array:
    223   case Vector:
    224     return true;
    225   case Int:
    226     return getInt().needsCleanup();
    227   case Float:
    228     return getFloat().needsCleanup();
    229   case ComplexFloat:
    230     assert(getComplexFloatImag().needsCleanup() ==
    231                getComplexFloatReal().needsCleanup() &&
    232            "In _Complex float types, real and imaginary values always have the "
    233            "same size.");
    234     return getComplexFloatReal().needsCleanup();
    235   case ComplexInt:
    236     assert(getComplexIntImag().needsCleanup() ==
    237                getComplexIntReal().needsCleanup() &&
    238            "In _Complex int types, real and imaginary values must have the "
    239            "same size.");
    240     return getComplexIntReal().needsCleanup();
    241   case LValue:
    242     return reinterpret_cast<const LV *>(Data)->hasPathPtr();
    243   case MemberPointer:
    244     return reinterpret_cast<const MemberPointerData *>(Data)->hasPathPtr();
    245   }
    246   llvm_unreachable("Unknown APValue kind!");
    247 }
    248 
    249 void APValue::swap(APValue &RHS) {
    250   std::swap(Kind, RHS.Kind);
    251   char TmpData[MaxSize];
    252   memcpy(TmpData, Data, MaxSize);
    253   memcpy(Data, RHS.Data, MaxSize);
    254   memcpy(RHS.Data, TmpData, MaxSize);
    255 }
    256 
    257 void APValue::dump() const {
    258   dump(llvm::errs());
    259   llvm::errs() << '\n';
    260 }
    261 
    262 static double GetApproxValue(const llvm::APFloat &F) {
    263   llvm::APFloat V = F;
    264   bool ignored;
    265   V.convert(llvm::APFloat::IEEEdouble, llvm::APFloat::rmNearestTiesToEven,
    266             &ignored);
    267   return V.convertToDouble();
    268 }
    269 
    270 void APValue::dump(raw_ostream &OS) const {
    271   switch (getKind()) {
    272   case Uninitialized:
    273     OS << "Uninitialized";
    274     return;
    275   case Int:
    276     OS << "Int: " << getInt();
    277     return;
    278   case Float:
    279     OS << "Float: " << GetApproxValue(getFloat());
    280     return;
    281   case Vector:
    282     OS << "Vector: ";
    283     getVectorElt(0).dump(OS);
    284     for (unsigned i = 1; i != getVectorLength(); ++i) {
    285       OS << ", ";
    286       getVectorElt(i).dump(OS);
    287     }
    288     return;
    289   case ComplexInt:
    290     OS << "ComplexInt: " << getComplexIntReal() << ", " << getComplexIntImag();
    291     return;
    292   case ComplexFloat:
    293     OS << "ComplexFloat: " << GetApproxValue(getComplexFloatReal())
    294        << ", " << GetApproxValue(getComplexFloatImag());
    295     return;
    296   case LValue:
    297     OS << "LValue: <todo>";
    298     return;
    299   case Array:
    300     OS << "Array: ";
    301     for (unsigned I = 0, N = getArrayInitializedElts(); I != N; ++I) {
    302       getArrayInitializedElt(I).dump(OS);
    303       if (I != getArraySize() - 1) OS << ", ";
    304     }
    305     if (hasArrayFiller()) {
    306       OS << getArraySize() - getArrayInitializedElts() << " x ";
    307       getArrayFiller().dump(OS);
    308     }
    309     return;
    310   case Struct:
    311     OS << "Struct ";
    312     if (unsigned N = getStructNumBases()) {
    313       OS << " bases: ";
    314       getStructBase(0).dump(OS);
    315       for (unsigned I = 1; I != N; ++I) {
    316         OS << ", ";
    317         getStructBase(I).dump(OS);
    318       }
    319     }
    320     if (unsigned N = getStructNumFields()) {
    321       OS << " fields: ";
    322       getStructField(0).dump(OS);
    323       for (unsigned I = 1; I != N; ++I) {
    324         OS << ", ";
    325         getStructField(I).dump(OS);
    326       }
    327     }
    328     return;
    329   case Union:
    330     OS << "Union: ";
    331     getUnionValue().dump(OS);
    332     return;
    333   case MemberPointer:
    334     OS << "MemberPointer: <todo>";
    335     return;
    336   case AddrLabelDiff:
    337     OS << "AddrLabelDiff: <todo>";
    338     return;
    339   }
    340   llvm_unreachable("Unknown APValue kind!");
    341 }
    342 
    343 void APValue::printPretty(raw_ostream &Out, ASTContext &Ctx, QualType Ty) const{
    344   switch (getKind()) {
    345   case APValue::Uninitialized:
    346     Out << "<uninitialized>";
    347     return;
    348   case APValue::Int:
    349     if (Ty->isBooleanType())
    350       Out << (getInt().getBoolValue() ? "true" : "false");
    351     else
    352       Out << getInt();
    353     return;
    354   case APValue::Float:
    355     Out << GetApproxValue(getFloat());
    356     return;
    357   case APValue::Vector: {
    358     Out << '{';
    359     QualType ElemTy = Ty->getAs<VectorType>()->getElementType();
    360     getVectorElt(0).printPretty(Out, Ctx, ElemTy);
    361     for (unsigned i = 1; i != getVectorLength(); ++i) {
    362       Out << ", ";
    363       getVectorElt(i).printPretty(Out, Ctx, ElemTy);
    364     }
    365     Out << '}';
    366     return;
    367   }
    368   case APValue::ComplexInt:
    369     Out << getComplexIntReal() << "+" << getComplexIntImag() << "i";
    370     return;
    371   case APValue::ComplexFloat:
    372     Out << GetApproxValue(getComplexFloatReal()) << "+"
    373         << GetApproxValue(getComplexFloatImag()) << "i";
    374     return;
    375   case APValue::LValue: {
    376     LValueBase Base = getLValueBase();
    377     if (!Base) {
    378       Out << "0";
    379       return;
    380     }
    381 
    382     bool IsReference = Ty->isReferenceType();
    383     QualType InnerTy
    384       = IsReference ? Ty.getNonReferenceType() : Ty->getPointeeType();
    385     if (InnerTy.isNull())
    386       InnerTy = Ty;
    387 
    388     if (!hasLValuePath()) {
    389       // No lvalue path: just print the offset.
    390       CharUnits O = getLValueOffset();
    391       CharUnits S = Ctx.getTypeSizeInChars(InnerTy);
    392       if (!O.isZero()) {
    393         if (IsReference)
    394           Out << "*(";
    395         if (O % S) {
    396           Out << "(char*)";
    397           S = CharUnits::One();
    398         }
    399         Out << '&';
    400       } else if (!IsReference)
    401         Out << '&';
    402 
    403       if (const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>())
    404         Out << *VD;
    405       else
    406         Base.get<const Expr*>()->printPretty(Out, 0, Ctx.getPrintingPolicy());
    407       if (!O.isZero()) {
    408         Out << " + " << (O / S);
    409         if (IsReference)
    410           Out << ')';
    411       }
    412       return;
    413     }
    414 
    415     // We have an lvalue path. Print it out nicely.
    416     if (!IsReference)
    417       Out << '&';
    418     else if (isLValueOnePastTheEnd())
    419       Out << "*(&";
    420 
    421     QualType ElemTy;
    422     if (const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>()) {
    423       Out << *VD;
    424       ElemTy = VD->getType();
    425     } else {
    426       const Expr *E = Base.get<const Expr*>();
    427       E->printPretty(Out, 0, Ctx.getPrintingPolicy());
    428       ElemTy = E->getType();
    429     }
    430 
    431     ArrayRef<LValuePathEntry> Path = getLValuePath();
    432     const CXXRecordDecl *CastToBase = 0;
    433     for (unsigned I = 0, N = Path.size(); I != N; ++I) {
    434       if (ElemTy->getAs<RecordType>()) {
    435         // The lvalue refers to a class type, so the next path entry is a base
    436         // or member.
    437         const Decl *BaseOrMember =
    438         BaseOrMemberType::getFromOpaqueValue(Path[I].BaseOrMember).getPointer();
    439         if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(BaseOrMember)) {
    440           CastToBase = RD;
    441           ElemTy = Ctx.getRecordType(RD);
    442         } else {
    443           const ValueDecl *VD = cast<ValueDecl>(BaseOrMember);
    444           Out << ".";
    445           if (CastToBase)
    446             Out << *CastToBase << "::";
    447           Out << *VD;
    448           ElemTy = VD->getType();
    449         }
    450       } else {
    451         // The lvalue must refer to an array.
    452         Out << '[' << Path[I].ArrayIndex << ']';
    453         ElemTy = Ctx.getAsArrayType(ElemTy)->getElementType();
    454       }
    455     }
    456 
    457     // Handle formatting of one-past-the-end lvalues.
    458     if (isLValueOnePastTheEnd()) {
    459       // FIXME: If CastToBase is non-0, we should prefix the output with
    460       // "(CastToBase*)".
    461       Out << " + 1";
    462       if (IsReference)
    463         Out << ')';
    464     }
    465     return;
    466   }
    467   case APValue::Array: {
    468     const ArrayType *AT = Ctx.getAsArrayType(Ty);
    469     QualType ElemTy = AT->getElementType();
    470     Out << '{';
    471     if (unsigned N = getArrayInitializedElts()) {
    472       getArrayInitializedElt(0).printPretty(Out, Ctx, ElemTy);
    473       for (unsigned I = 1; I != N; ++I) {
    474         Out << ", ";
    475         if (I == 10) {
    476           // Avoid printing out the entire contents of large arrays.
    477           Out << "...";
    478           break;
    479         }
    480         getArrayInitializedElt(I).printPretty(Out, Ctx, ElemTy);
    481       }
    482     }
    483     Out << '}';
    484     return;
    485   }
    486   case APValue::Struct: {
    487     Out << '{';
    488     const RecordDecl *RD = Ty->getAs<RecordType>()->getDecl();
    489     bool First = true;
    490     if (unsigned N = getStructNumBases()) {
    491       const CXXRecordDecl *CD = cast<CXXRecordDecl>(RD);
    492       CXXRecordDecl::base_class_const_iterator BI = CD->bases_begin();
    493       for (unsigned I = 0; I != N; ++I, ++BI) {
    494         assert(BI != CD->bases_end());
    495         if (!First)
    496           Out << ", ";
    497         getStructBase(I).printPretty(Out, Ctx, BI->getType());
    498         First = false;
    499       }
    500     }
    501     for (RecordDecl::field_iterator FI = RD->field_begin();
    502          FI != RD->field_end(); ++FI) {
    503       if (!First)
    504         Out << ", ";
    505       if (FI->isUnnamedBitfield()) continue;
    506       getStructField(FI->getFieldIndex()).
    507         printPretty(Out, Ctx, FI->getType());
    508       First = false;
    509     }
    510     Out << '}';
    511     return;
    512   }
    513   case APValue::Union:
    514     Out << '{';
    515     if (const FieldDecl *FD = getUnionField()) {
    516       Out << "." << *FD << " = ";
    517       getUnionValue().printPretty(Out, Ctx, FD->getType());
    518     }
    519     Out << '}';
    520     return;
    521   case APValue::MemberPointer:
    522     // FIXME: This is not enough to unambiguously identify the member in a
    523     // multiple-inheritance scenario.
    524     if (const ValueDecl *VD = getMemberPointerDecl()) {
    525       Out << '&' << *cast<CXXRecordDecl>(VD->getDeclContext()) << "::" << *VD;
    526       return;
    527     }
    528     Out << "0";
    529     return;
    530   case APValue::AddrLabelDiff:
    531     Out << "&&" << getAddrLabelDiffLHS()->getLabel()->getName();
    532     Out << " - ";
    533     Out << "&&" << getAddrLabelDiffRHS()->getLabel()->getName();
    534     return;
    535   }
    536   llvm_unreachable("Unknown APValue kind!");
    537 }
    538 
    539 std::string APValue::getAsString(ASTContext &Ctx, QualType Ty) const {
    540   std::string Result;
    541   llvm::raw_string_ostream Out(Result);
    542   printPretty(Out, Ctx, Ty);
    543   Out.flush();
    544   return Result;
    545 }
    546 
    547 const APValue::LValueBase APValue::getLValueBase() const {
    548   assert(isLValue() && "Invalid accessor");
    549   return ((const LV*)(const void*)Data)->BaseAndIsOnePastTheEnd.getPointer();
    550 }
    551 
    552 bool APValue::isLValueOnePastTheEnd() const {
    553   assert(isLValue() && "Invalid accessor");
    554   return ((const LV*)(const void*)Data)->BaseAndIsOnePastTheEnd.getInt();
    555 }
    556 
    557 CharUnits &APValue::getLValueOffset() {
    558   assert(isLValue() && "Invalid accessor");
    559   return ((LV*)(void*)Data)->Offset;
    560 }
    561 
    562 bool APValue::hasLValuePath() const {
    563   assert(isLValue() && "Invalid accessor");
    564   return ((const LV*)(const char*)Data)->hasPath();
    565 }
    566 
    567 ArrayRef<APValue::LValuePathEntry> APValue::getLValuePath() const {
    568   assert(isLValue() && hasLValuePath() && "Invalid accessor");
    569   const LV &LVal = *((const LV*)(const char*)Data);
    570   return ArrayRef<LValuePathEntry>(LVal.getPath(), LVal.PathLength);
    571 }
    572 
    573 unsigned APValue::getLValueCallIndex() const {
    574   assert(isLValue() && "Invalid accessor");
    575   return ((const LV*)(const char*)Data)->CallIndex;
    576 }
    577 
    578 void APValue::setLValue(LValueBase B, const CharUnits &O, NoLValuePath,
    579                         unsigned CallIndex) {
    580   assert(isLValue() && "Invalid accessor");
    581   LV &LVal = *((LV*)(char*)Data);
    582   LVal.BaseAndIsOnePastTheEnd.setPointer(B);
    583   LVal.BaseAndIsOnePastTheEnd.setInt(false);
    584   LVal.Offset = O;
    585   LVal.CallIndex = CallIndex;
    586   LVal.resizePath((unsigned)-1);
    587 }
    588 
    589 void APValue::setLValue(LValueBase B, const CharUnits &O,
    590                         ArrayRef<LValuePathEntry> Path, bool IsOnePastTheEnd,
    591                         unsigned CallIndex) {
    592   assert(isLValue() && "Invalid accessor");
    593   LV &LVal = *((LV*)(char*)Data);
    594   LVal.BaseAndIsOnePastTheEnd.setPointer(B);
    595   LVal.BaseAndIsOnePastTheEnd.setInt(IsOnePastTheEnd);
    596   LVal.Offset = O;
    597   LVal.CallIndex = CallIndex;
    598   LVal.resizePath(Path.size());
    599   memcpy(LVal.getPath(), Path.data(), Path.size() * sizeof(LValuePathEntry));
    600 }
    601 
    602 const ValueDecl *APValue::getMemberPointerDecl() const {
    603   assert(isMemberPointer() && "Invalid accessor");
    604   const MemberPointerData &MPD = *((const MemberPointerData*)(const char*)Data);
    605   return MPD.MemberAndIsDerivedMember.getPointer();
    606 }
    607 
    608 bool APValue::isMemberPointerToDerivedMember() const {
    609   assert(isMemberPointer() && "Invalid accessor");
    610   const MemberPointerData &MPD = *((const MemberPointerData*)(const char*)Data);
    611   return MPD.MemberAndIsDerivedMember.getInt();
    612 }
    613 
    614 ArrayRef<const CXXRecordDecl*> APValue::getMemberPointerPath() const {
    615   assert(isMemberPointer() && "Invalid accessor");
    616   const MemberPointerData &MPD = *((const MemberPointerData*)(const char*)Data);
    617   return ArrayRef<const CXXRecordDecl*>(MPD.getPath(), MPD.PathLength);
    618 }
    619 
    620 void APValue::MakeLValue() {
    621   assert(isUninit() && "Bad state change");
    622   assert(sizeof(LV) <= MaxSize && "LV too big");
    623   new ((void*)(char*)Data) LV();
    624   Kind = LValue;
    625 }
    626 
    627 void APValue::MakeArray(unsigned InitElts, unsigned Size) {
    628   assert(isUninit() && "Bad state change");
    629   new ((void*)(char*)Data) Arr(InitElts, Size);
    630   Kind = Array;
    631 }
    632 
    633 void APValue::MakeMemberPointer(const ValueDecl *Member, bool IsDerivedMember,
    634                                 ArrayRef<const CXXRecordDecl*> Path) {
    635   assert(isUninit() && "Bad state change");
    636   MemberPointerData *MPD = new ((void*)(char*)Data) MemberPointerData;
    637   Kind = MemberPointer;
    638   MPD->MemberAndIsDerivedMember.setPointer(Member);
    639   MPD->MemberAndIsDerivedMember.setInt(IsDerivedMember);
    640   MPD->resizePath(Path.size());
    641   memcpy(MPD->getPath(), Path.data(), Path.size()*sizeof(const CXXRecordDecl*));
    642 }
    643