external/bsd/llvm/dist/clang/lib/AST/APValue.cpp

   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       (DataSize - 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       (DataSize - 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(nullptr), 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.buffer)->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.buffer)->~APSInt();
 192   else if (Kind == Float)
 193     ((APFloat*)(char*)Data.buffer)->~APFloat();
 194   else if (Kind == Vector)
 195     ((Vec*)(char*)Data.buffer)->~Vec();
 196   else if (Kind == ComplexInt)
 197     ((ComplexAPSInt*)(char*)Data.buffer)->~ComplexAPSInt();
 198   else if (Kind == ComplexFloat)
 199     ((ComplexAPFloat*)(char*)Data.buffer)->~ComplexAPFloat();
 200   else if (Kind == LValue)
 201     ((LV*)(char*)Data.buffer)->~LV();
 202   else if (Kind == Array)
 203     ((Arr*)(char*)Data.buffer)->~Arr();
 204   else if (Kind == Struct)
 205     ((StructData*)(char*)Data.buffer)->~StructData();
 206   else if (Kind == Union)
 207     ((UnionData*)(char*)Data.buffer)->~UnionData();
 208   else if (Kind == MemberPointer)
 209     ((MemberPointerData*)(char*)Data.buffer)->~MemberPointerData();
 210   else if (Kind == AddrLabelDiff)
 211     ((AddrLabelDiffData*)(char*)Data.buffer)->~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.buffer)->hasPathPtr();
 243   case MemberPointer:
 244     return reinterpret_cast<const MemberPointerData *>(Data.buffer)
 245         ->hasPathPtr();
 246   }
 247   llvm_unreachable("Unknown APValue kind!");
 248 }
 249
 250 void APValue::swap(APValue &RHS) {
 251   std::swap(Kind, RHS.Kind);
 252   char TmpData[DataSize];
 253   memcpy(TmpData, Data.buffer, DataSize);
 254   memcpy(Data.buffer, RHS.Data.buffer, DataSize);
 255   memcpy(RHS.Data.buffer, TmpData, DataSize);
 256 }
 257
 258 void APValue::dump() const {
 259   dump(llvm::errs());
 260   llvm::errs() << '\n';
 261 }
 262
 263 static double GetApproxValue(const llvm::APFloat &F) {
 264   llvm::APFloat V = F;
 265   bool ignored;
 266   V.convert(llvm::APFloat::IEEEdouble, llvm::APFloat::rmNearestTiesToEven,
 267             &ignored);
 268   return V.convertToDouble();
 269 }
 270
 271 void APValue::dump(raw_ostream &OS) const {
 272   switch (getKind()) {
 273   case Uninitialized:
 274     OS << "Uninitialized";
 275     return;
 276   case Int:
 277     OS << "Int: " << getInt();
 278     return;
 279   case Float:
 280     OS << "Float: " << GetApproxValue(getFloat());
 281     return;
 282   case Vector:
 283     OS << "Vector: ";
 284     getVectorElt(0).dump(OS);
 285     for (unsigned i = 1; i != getVectorLength(); ++i) {
 286       OS << ", ";
 287       getVectorElt(i).dump(OS);
 288     }
 289     return;
 290   case ComplexInt:
 291     OS << "ComplexInt: " << getComplexIntReal() << ", " << getComplexIntImag();
 292     return;
 293   case ComplexFloat:
 294     OS << "ComplexFloat: " << GetApproxValue(getComplexFloatReal())
 295        << ", " << GetApproxValue(getComplexFloatImag());
 296     return;
 297   case LValue:
 298     OS << "LValue: <todo>";
 299     return;
 300   case Array:
 301     OS << "Array: ";
 302     for (unsigned I = 0, N = getArrayInitializedElts(); I != N; ++I) {
 303       getArrayInitializedElt(I).dump(OS);
 304       if (I != getArraySize() - 1) OS << ", ";
 305     }
 306     if (hasArrayFiller()) {
 307       OS << getArraySize() - getArrayInitializedElts() << " x ";
 308       getArrayFiller().dump(OS);
 309     }
 310     return;
 311   case Struct:
 312     OS << "Struct ";
 313     if (unsigned N = getStructNumBases()) {
 314       OS << " bases: ";
 315       getStructBase(0).dump(OS);
 316       for (unsigned I = 1; I != N; ++I) {
 317         OS << ", ";
 318         getStructBase(I).dump(OS);
 319       }
 320     }
 321     if (unsigned N = getStructNumFields()) {
 322       OS << " fields: ";
 323       getStructField(0).dump(OS);
 324       for (unsigned I = 1; I != N; ++I) {
 325         OS << ", ";
 326         getStructField(I).dump(OS);
 327       }
 328     }
 329     return;
 330   case Union:
 331     OS << "Union: ";
 332     getUnionValue().dump(OS);
 333     return;
 334   case MemberPointer:
 335     OS << "MemberPointer: <todo>";
 336     return;
 337   case AddrLabelDiff:
 338     OS << "AddrLabelDiff: <todo>";
 339     return;
 340   }
 341   llvm_unreachable("Unknown APValue kind!");
 342 }
 343
 344 void APValue::printPretty(raw_ostream &Out, ASTContext &Ctx, QualType Ty) const{
 345   switch (getKind()) {
 346   case APValue::Uninitialized:
 347     Out << "<uninitialized>";
 348     return;
 349   case APValue::Int:
 350     if (Ty->isBooleanType())
 351       Out << (getInt().getBoolValue() ? "true" : "false");
 352     else
 353       Out << getInt();
 354     return;
 355   case APValue::Float:
 356     Out << GetApproxValue(getFloat());
 357     return;
 358   case APValue::Vector: {
 359     Out << '{';
 360     QualType ElemTy = Ty->getAs<VectorType>()->getElementType();
 361     getVectorElt(0).printPretty(Out, Ctx, ElemTy);
 362     for (unsigned i = 1; i != getVectorLength(); ++i) {
 363       Out << ", ";
 364       getVectorElt(i).printPretty(Out, Ctx, ElemTy);
 365     }
 366     Out << '}';
 367     return;
 368   }
 369   case APValue::ComplexInt:
 370     Out << getComplexIntReal() << "+" << getComplexIntImag() << "i";
 371     return;
 372   case APValue::ComplexFloat:
 373     Out << GetApproxValue(getComplexFloatReal()) << "+"
 374         << GetApproxValue(getComplexFloatImag()) << "i";
 375     return;
 376   case APValue::LValue: {
 377     LValueBase Base = getLValueBase();
 378     if (!Base) {
 379       Out << "0";
 380       return;
 381     }
 382
 383     bool IsReference = Ty->isReferenceType();
 384     QualType InnerTy
 385       = IsReference ? Ty.getNonReferenceType() : Ty->getPointeeType();
 386     if (InnerTy.isNull())
 387       InnerTy = Ty;
 388
 389     if (!hasLValuePath()) {
 390       // No lvalue path: just print the offset.
 391       CharUnits O = getLValueOffset();
 392       CharUnits S = Ctx.getTypeSizeInChars(InnerTy);
 393       if (!O.isZero()) {
 394         if (IsReference)
 395           Out << "*(";
 396         if (O % S) {
 397           Out << "(char*)";
 398           S = CharUnits::One();
 399         }
 400         Out << '&';
 401       } else if (!IsReference)
 402         Out << '&';
 403
 404       if (const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>())
 405         Out << *VD;
 406       else {
 407         assert(Base.get<const Expr *>() != nullptr &&
 408                "Expecting non-null Expr");
 409         Base.get<const Expr*>()->printPretty(Out, nullptr,
 410                                              Ctx.getPrintingPolicy());
 411       }
 412
 413       if (!O.isZero()) {
 414         Out << " + " << (O / S);
 415         if (IsReference)
 416           Out << ')';
 417       }
 418       return;
 419     }
 420
 421     // We have an lvalue path. Print it out nicely.
 422     if (!IsReference)
 423       Out << '&';
 424     else if (isLValueOnePastTheEnd())
 425       Out << "*(&";
 426
 427     QualType ElemTy;
 428     if (const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>()) {
 429       Out << *VD;
 430       ElemTy = VD->getType();
 431     } else {
 432       const Expr *E = Base.get<const Expr*>();
 433       assert(E != nullptr && "Expecting non-null Expr");
 434       E->printPretty(Out, nullptr, Ctx.getPrintingPolicy());
 435       ElemTy = E->getType();
 436     }
 437
 438     ArrayRef<LValuePathEntry> Path = getLValuePath();
 439     const CXXRecordDecl *CastToBase = nullptr;
 440     for (unsigned I = 0, N = Path.size(); I != N; ++I) {
 441       if (ElemTy->getAs<RecordType>()) {
 442         // The lvalue refers to a class type, so the next path entry is a base
 443         // or member.
 444         const Decl *BaseOrMember =
 445         BaseOrMemberType::getFromOpaqueValue(Path[I].BaseOrMember).getPointer();
 446         if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(BaseOrMember)) {
 447           CastToBase = RD;
 448           ElemTy = Ctx.getRecordType(RD);
 449         } else {
 450           const ValueDecl *VD = cast<ValueDecl>(BaseOrMember);
 451           Out << ".";
 452           if (CastToBase)
 453             Out << *CastToBase << "::";
 454           Out << *VD;
 455           ElemTy = VD->getType();
 456         }
 457       } else {
 458         // The lvalue must refer to an array.
 459         Out << '[' << Path[I].ArrayIndex << ']';
 460         ElemTy = Ctx.getAsArrayType(ElemTy)->getElementType();
 461       }
 462     }
 463
 464     // Handle formatting of one-past-the-end lvalues.
 465     if (isLValueOnePastTheEnd()) {
 466       // FIXME: If CastToBase is non-0, we should prefix the output with
 467       // "(CastToBase*)".
 468       Out << " + 1";
 469       if (IsReference)
 470         Out << ')';
 471     }
 472     return;
 473   }
 474   case APValue::Array: {
 475     const ArrayType *AT = Ctx.getAsArrayType(Ty);
 476     QualType ElemTy = AT->getElementType();
 477     Out << '{';
 478     if (unsigned N = getArrayInitializedElts()) {
 479       getArrayInitializedElt(0).printPretty(Out, Ctx, ElemTy);
 480       for (unsigned I = 1; I != N; ++I) {
 481         Out << ", ";
 482         if (I == 10) {
 483           // Avoid printing out the entire contents of large arrays.
 484           Out << "...";
 485           break;
 486         }
 487         getArrayInitializedElt(I).printPretty(Out, Ctx, ElemTy);
 488       }
 489     }
 490     Out << '}';
 491     return;
 492   }
 493   case APValue::Struct: {
 494     Out << '{';
 495     const RecordDecl *RD = Ty->getAs<RecordType>()->getDecl();
 496     bool First = true;
 497     if (unsigned N = getStructNumBases()) {
 498       const CXXRecordDecl *CD = cast<CXXRecordDecl>(RD);
 499       CXXRecordDecl::base_class_const_iterator BI = CD->bases_begin();
 500       for (unsigned I = 0; I != N; ++I, ++BI) {
 501         assert(BI != CD->bases_end());
 502         if (!First)
 503           Out << ", ";
 504         getStructBase(I).printPretty(Out, Ctx, BI->getType());
 505         First = false;
 506       }
 507     }
 508     for (const auto *FI : RD->fields()) {
 509       if (!First)
 510         Out << ", ";
 511       if (FI->isUnnamedBitfield()) continue;
 512       getStructField(FI->getFieldIndex()).
 513         printPretty(Out, Ctx, FI->getType());
 514       First = false;
 515     }
 516     Out << '}';
 517     return;
 518   }
 519   case APValue::Union:
 520     Out << '{';
 521     if (const FieldDecl *FD = getUnionField()) {
 522       Out << "." << *FD << " = ";
 523       getUnionValue().printPretty(Out, Ctx, FD->getType());
 524     }
 525     Out << '}';
 526     return;
 527   case APValue::MemberPointer:
 528     // FIXME: This is not enough to unambiguously identify the member in a
 529     // multiple-inheritance scenario.
 530     if (const ValueDecl *VD = getMemberPointerDecl()) {
 531       Out << '&' << *cast<CXXRecordDecl>(VD->getDeclContext()) << "::" << *VD;
 532       return;
 533     }
 534     Out << "0";
 535     return;
 536   case APValue::AddrLabelDiff:
 537     Out << "&&" << getAddrLabelDiffLHS()->getLabel()->getName();
 538     Out << " - ";
 539     Out << "&&" << getAddrLabelDiffRHS()->getLabel()->getName();
 540     return;
 541   }
 542   llvm_unreachable("Unknown APValue kind!");
 543 }
 544
 545 std::string APValue::getAsString(ASTContext &Ctx, QualType Ty) const {
 546   std::string Result;
 547   llvm::raw_string_ostream Out(Result);
 548   printPretty(Out, Ctx, Ty);
 549   Out.flush();
 550   return Result;
 551 }
 552
 553 const APValue::LValueBase APValue::getLValueBase() const {
 554   assert(isLValue() && "Invalid accessor");
 555   return ((const LV*)(const void*)Data.buffer)->BaseAndIsOnePastTheEnd.getPointer();
 556 }
 557
 558 bool APValue::isLValueOnePastTheEnd() const {
 559   assert(isLValue() && "Invalid accessor");
 560   return ((const LV*)(const void*)Data.buffer)->BaseAndIsOnePastTheEnd.getInt();
 561 }
 562
 563 CharUnits &APValue::getLValueOffset() {
 564   assert(isLValue() && "Invalid accessor");
 565   return ((LV*)(void*)Data.buffer)->Offset;
 566 }
 567
 568 bool APValue::hasLValuePath() const {
 569   assert(isLValue() && "Invalid accessor");
 570   return ((const LV*)(const char*)Data.buffer)->hasPath();
 571 }
 572
 573 ArrayRef<APValue::LValuePathEntry> APValue::getLValuePath() const {
 574   assert(isLValue() && hasLValuePath() && "Invalid accessor");
 575   const LV &LVal = *((const LV*)(const char*)Data.buffer);
 576   return llvm::makeArrayRef(LVal.getPath(), LVal.PathLength);
 577 }
 578
 579 unsigned APValue::getLValueCallIndex() const {
 580   assert(isLValue() && "Invalid accessor");
 581   return ((const LV*)(const char*)Data.buffer)->CallIndex;
 582 }
 583
 584 void APValue::setLValue(LValueBase B, const CharUnits &O, NoLValuePath,
 585                         unsigned CallIndex) {
 586   assert(isLValue() && "Invalid accessor");
 587   LV &LVal = *((LV*)(char*)Data.buffer);
 588   LVal.BaseAndIsOnePastTheEnd.setPointer(B);
 589   LVal.BaseAndIsOnePastTheEnd.setInt(false);
 590   LVal.Offset = O;
 591   LVal.CallIndex = CallIndex;
 592   LVal.resizePath((unsigned)-1);
 593 }
 594
 595 void APValue::setLValue(LValueBase B, const CharUnits &O,
 596                         ArrayRef<LValuePathEntry> Path, bool IsOnePastTheEnd,
 597                         unsigned CallIndex) {
 598   assert(isLValue() && "Invalid accessor");
 599   LV &LVal = *((LV*)(char*)Data.buffer);
 600   LVal.BaseAndIsOnePastTheEnd.setPointer(B);
 601   LVal.BaseAndIsOnePastTheEnd.setInt(IsOnePastTheEnd);
 602   LVal.Offset = O;
 603   LVal.CallIndex = CallIndex;
 604   LVal.resizePath(Path.size());
 605   memcpy(LVal.getPath(), Path.data(), Path.size() * sizeof(LValuePathEntry));
 606 }
 607
 608 const ValueDecl *APValue::getMemberPointerDecl() const {
 609   assert(isMemberPointer() && "Invalid accessor");
 610   const MemberPointerData &MPD =
 611       *((const MemberPointerData *)(const char *)Data.buffer);
 612   return MPD.MemberAndIsDerivedMember.getPointer();
 613 }
 614
 615 bool APValue::isMemberPointerToDerivedMember() const {
 616   assert(isMemberPointer() && "Invalid accessor");
 617   const MemberPointerData &MPD =
 618       *((const MemberPointerData *)(const char *)Data.buffer);
 619   return MPD.MemberAndIsDerivedMember.getInt();
 620 }
 621
 622 ArrayRef<const CXXRecordDecl*> APValue::getMemberPointerPath() const {
 623   assert(isMemberPointer() && "Invalid accessor");
 624   const MemberPointerData &MPD =
 625       *((const MemberPointerData *)(const char *)Data.buffer);
 626   return llvm::makeArrayRef(MPD.getPath(), MPD.PathLength);
 627 }
 628
 629 void APValue::MakeLValue() {
 630   assert(isUninit() && "Bad state change");
 631   static_assert(sizeof(LV) <= DataSize, "LV too big");
 632   new ((void*)(char*)Data.buffer) LV();
 633   Kind = LValue;
 634 }
 635
 636 void APValue::MakeArray(unsigned InitElts, unsigned Size) {
 637   assert(isUninit() && "Bad state change");
 638   new ((void*)(char*)Data.buffer) Arr(InitElts, Size);
 639   Kind = Array;
 640 }
 641
 642 void APValue::MakeMemberPointer(const ValueDecl *Member, bool IsDerivedMember,
 643                                 ArrayRef<const CXXRecordDecl*> Path) {
 644   assert(isUninit() && "Bad state change");
 645   MemberPointerData *MPD = new ((void*)(char*)Data.buffer) MemberPointerData;
 646   Kind = MemberPointer;
 647   MPD->MemberAndIsDerivedMember.setPointer(Member);
 648   MPD->MemberAndIsDerivedMember.setInt(IsDerivedMember);
 649   MPD->resizePath(Path.size());
 650   memcpy(MPD->getPath(), Path.data(), Path.size()*sizeof(const CXXRecordDecl*));
 651 }