1//===--- APValue.cpp - Union class for APFloat/APSInt/Complex -------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9//  This file implements the APValue class.
10//
11//===----------------------------------------------------------------------===//
12
13#include "clang/AST/APValue.h"
14#include "clang/AST/ASTContext.h"
15#include "clang/AST/CharUnits.h"
16#include "clang/AST/DeclCXX.h"
17#include "clang/AST/Expr.h"
18#include "clang/AST/Type.h"
19#include "llvm/Support/ErrorHandling.h"
20#include "llvm/Support/raw_ostream.h"
21using namespace clang;
22
23/// The identity of a type_info object depends on the canonical unqualified
24/// type only.
25TypeInfoLValue::TypeInfoLValue(const Type *T)
26    : T(T->getCanonicalTypeUnqualified().getTypePtr()) {}
27
28void TypeInfoLValue::print(llvm::raw_ostream &Out,
29                           const PrintingPolicy &Policy) const {
30  Out << "typeid(";
31  QualType(getType(), 0).print(Out, Policy);
32  Out << ")";
33}
34
35static_assert(
36    1 << llvm::PointerLikeTypeTraits<TypeInfoLValue>::NumLowBitsAvailable <=
37        alignof(Type),
38    "Type is insufficiently aligned");
39
40APValue::LValueBase::LValueBase(const ValueDecl *P, unsigned I, unsigned V)
41    : Ptr(P), Local{I, V} {}
42APValue::LValueBase::LValueBase(const Expr *P, unsigned I, unsigned V)
43    : Ptr(P), Local{I, V} {}
44
45APValue::LValueBase APValue::LValueBase::getDynamicAlloc(DynamicAllocLValue LV,
46                                                         QualType Type) {
47  LValueBase Base;
48  Base.Ptr = LV;
49  Base.DynamicAllocType = Type.getAsOpaquePtr();
50  return Base;
51}
52
53APValue::LValueBase APValue::LValueBase::getTypeInfo(TypeInfoLValue LV,
54                                                     QualType TypeInfo) {
55  LValueBase Base;
56  Base.Ptr = LV;
57  Base.TypeInfoType = TypeInfo.getAsOpaquePtr();
58  return Base;
59}
60
61unsigned APValue::LValueBase::getCallIndex() const {
62  return (is<TypeInfoLValue>() || is<DynamicAllocLValue>()) ? 0
63                                                            : Local.CallIndex;
64}
65
66unsigned APValue::LValueBase::getVersion() const {
67  return (is<TypeInfoLValue>() || is<DynamicAllocLValue>()) ? 0 : Local.Version;
68}
69
70QualType APValue::LValueBase::getTypeInfoType() const {
71  assert(is<TypeInfoLValue>() && "not a type_info lvalue");
72  return QualType::getFromOpaquePtr(TypeInfoType);
73}
74
75QualType APValue::LValueBase::getDynamicAllocType() const {
76  assert(is<DynamicAllocLValue>() && "not a dynamic allocation lvalue");
77  return QualType::getFromOpaquePtr(DynamicAllocType);
78}
79
80namespace clang {
81bool operator==(const APValue::LValueBase &LHS,
82                const APValue::LValueBase &RHS) {
83  if (LHS.Ptr != RHS.Ptr)
84    return false;
85  if (LHS.is<TypeInfoLValue>())
86    return true;
87  return LHS.Local.CallIndex == RHS.Local.CallIndex &&
88         LHS.Local.Version == RHS.Local.Version;
89}
90}
91
92namespace {
93  struct LVBase {
94    APValue::LValueBase Base;
95    CharUnits Offset;
96    unsigned PathLength;
97    bool IsNullPtr : 1;
98    bool IsOnePastTheEnd : 1;
99  };
100}
101
102void *APValue::LValueBase::getOpaqueValue() const {
103  return Ptr.getOpaqueValue();
104}
105
106bool APValue::LValueBase::isNull() const {
107  return Ptr.isNull();
108}
109
110APValue::LValueBase::operator bool () const {
111  return static_cast<bool>(Ptr);
112}
113
114clang::APValue::LValueBase
115llvm::DenseMapInfo<clang::APValue::LValueBase>::getEmptyKey() {
116  return clang::APValue::LValueBase(
117      DenseMapInfo<const ValueDecl*>::getEmptyKey());
118}
119
120clang::APValue::LValueBase
121llvm::DenseMapInfo<clang::APValue::LValueBase>::getTombstoneKey() {
122  return clang::APValue::LValueBase(
123      DenseMapInfo<const ValueDecl*>::getTombstoneKey());
124}
125
126namespace clang {
127llvm::hash_code hash_value(const APValue::LValueBase &Base) {
128  if (Base.is<TypeInfoLValue>() || Base.is<DynamicAllocLValue>())
129    return llvm::hash_value(Base.getOpaqueValue());
130  return llvm::hash_combine(Base.getOpaqueValue(), Base.getCallIndex(),
131                            Base.getVersion());
132}
133}
134
135unsigned llvm::DenseMapInfo<clang::APValue::LValueBase>::getHashValue(
136    const clang::APValue::LValueBase &Base) {
137  return hash_value(Base);
138}
139
140bool llvm::DenseMapInfo<clang::APValue::LValueBase>::isEqual(
141    const clang::APValue::LValueBase &LHS,
142    const clang::APValue::LValueBase &RHS) {
143  return LHS == RHS;
144}
145
146struct APValue::LV : LVBase {
147  static const unsigned InlinePathSpace =
148      (DataSize - sizeof(LVBase)) / sizeof(LValuePathEntry);
149
150  /// Path - The sequence of base classes, fields and array indices to follow to
151  /// walk from Base to the subobject. When performing GCC-style folding, there
152  /// may not be such a path.
153  union {
154    LValuePathEntry Path[InlinePathSpace];
155    LValuePathEntry *PathPtr;
156  };
157
158  LV() { PathLength = (unsigned)-1; }
159  ~LV() { resizePath(0); }
160
161  void resizePath(unsigned Length) {
162    if (Length == PathLength)
163      return;
164    if (hasPathPtr())
165      delete [] PathPtr;
166    PathLength = Length;
167    if (hasPathPtr())
168      PathPtr = new LValuePathEntry[Length];
169  }
170
171  bool hasPath() const { return PathLength != (unsigned)-1; }
172  bool hasPathPtr() const { return hasPath() && PathLength > InlinePathSpace; }
173
174  LValuePathEntry *getPath() { return hasPathPtr() ? PathPtr : Path; }
175  const LValuePathEntry *getPath() const {
176    return hasPathPtr() ? PathPtr : Path;
177  }
178};
179
180namespace {
181  struct MemberPointerBase {
182    llvm::PointerIntPair<const ValueDecl*, 1, bool> MemberAndIsDerivedMember;
183    unsigned PathLength;
184  };
185}
186
187struct APValue::MemberPointerData : MemberPointerBase {
188  static const unsigned InlinePathSpace =
189      (DataSize - sizeof(MemberPointerBase)) / sizeof(const CXXRecordDecl*);
190  typedef const CXXRecordDecl *PathElem;
191  union {
192    PathElem Path[InlinePathSpace];
193    PathElem *PathPtr;
194  };
195
196  MemberPointerData() { PathLength = 0; }
197  ~MemberPointerData() { resizePath(0); }
198
199  void resizePath(unsigned Length) {
200    if (Length == PathLength)
201      return;
202    if (hasPathPtr())
203      delete [] PathPtr;
204    PathLength = Length;
205    if (hasPathPtr())
206      PathPtr = new PathElem[Length];
207  }
208
209  bool hasPathPtr() const { return PathLength > InlinePathSpace; }
210
211  PathElem *getPath() { return hasPathPtr() ? PathPtr : Path; }
212  const PathElem *getPath() const {
213    return hasPathPtr() ? PathPtr : Path;
214  }
215};
216
217// FIXME: Reduce the malloc traffic here.
218
219APValue::Arr::Arr(unsigned NumElts, unsigned Size) :
220  Elts(new APValue[NumElts + (NumElts != Size ? 1 : 0)]),
221  NumElts(NumElts), ArrSize(Size) {}
222APValue::Arr::~Arr() { delete [] Elts; }
223
224APValue::StructData::StructData(unsigned NumBases, unsigned NumFields) :
225  Elts(new APValue[NumBases+NumFields]),
226  NumBases(NumBases), NumFields(NumFields) {}
227APValue::StructData::~StructData() {
228  delete [] Elts;
229}
230
231APValue::UnionData::UnionData() : Field(nullptr), Value(new APValue) {}
232APValue::UnionData::~UnionData () {
233  delete Value;
234}
235
236APValue::APValue(const APValue &RHS) : Kind(None) {
237  switch (RHS.getKind()) {
238  case None:
239  case Indeterminate:
240    Kind = RHS.getKind();
241    break;
242  case Int:
243    MakeInt();
244    setInt(RHS.getInt());
245    break;
246  case Float:
247    MakeFloat();
248    setFloat(RHS.getFloat());
249    break;
250  case FixedPoint: {
251    APFixedPoint FXCopy = RHS.getFixedPoint();
252    MakeFixedPoint(std::move(FXCopy));
253    break;
254  }
255  case Vector:
256    MakeVector();
257    setVector(((const Vec *)(const char *)RHS.Data.buffer)->Elts,
258              RHS.getVectorLength());
259    break;
260  case ComplexInt:
261    MakeComplexInt();
262    setComplexInt(RHS.getComplexIntReal(), RHS.getComplexIntImag());
263    break;
264  case ComplexFloat:
265    MakeComplexFloat();
266    setComplexFloat(RHS.getComplexFloatReal(), RHS.getComplexFloatImag());
267    break;
268  case LValue:
269    MakeLValue();
270    if (RHS.hasLValuePath())
271      setLValue(RHS.getLValueBase(), RHS.getLValueOffset(), RHS.getLValuePath(),
272                RHS.isLValueOnePastTheEnd(), RHS.isNullPointer());
273    else
274      setLValue(RHS.getLValueBase(), RHS.getLValueOffset(), NoLValuePath(),
275                RHS.isNullPointer());
276    break;
277  case Array:
278    MakeArray(RHS.getArrayInitializedElts(), RHS.getArraySize());
279    for (unsigned I = 0, N = RHS.getArrayInitializedElts(); I != N; ++I)
280      getArrayInitializedElt(I) = RHS.getArrayInitializedElt(I);
281    if (RHS.hasArrayFiller())
282      getArrayFiller() = RHS.getArrayFiller();
283    break;
284  case Struct:
285    MakeStruct(RHS.getStructNumBases(), RHS.getStructNumFields());
286    for (unsigned I = 0, N = RHS.getStructNumBases(); I != N; ++I)
287      getStructBase(I) = RHS.getStructBase(I);
288    for (unsigned I = 0, N = RHS.getStructNumFields(); I != N; ++I)
289      getStructField(I) = RHS.getStructField(I);
290    break;
291  case Union:
292    MakeUnion();
293    setUnion(RHS.getUnionField(), RHS.getUnionValue());
294    break;
295  case MemberPointer:
296    MakeMemberPointer(RHS.getMemberPointerDecl(),
297                      RHS.isMemberPointerToDerivedMember(),
298                      RHS.getMemberPointerPath());
299    break;
300  case AddrLabelDiff:
301    MakeAddrLabelDiff();
302    setAddrLabelDiff(RHS.getAddrLabelDiffLHS(), RHS.getAddrLabelDiffRHS());
303    break;
304  }
305}
306
307void APValue::DestroyDataAndMakeUninit() {
308  if (Kind == Int)
309    ((APSInt*)(char*)Data.buffer)->~APSInt();
310  else if (Kind == Float)
311    ((APFloat*)(char*)Data.buffer)->~APFloat();
312  else if (Kind == FixedPoint)
313    ((APFixedPoint *)(char *)Data.buffer)->~APFixedPoint();
314  else if (Kind == Vector)
315    ((Vec*)(char*)Data.buffer)->~Vec();
316  else if (Kind == ComplexInt)
317    ((ComplexAPSInt*)(char*)Data.buffer)->~ComplexAPSInt();
318  else if (Kind == ComplexFloat)
319    ((ComplexAPFloat*)(char*)Data.buffer)->~ComplexAPFloat();
320  else if (Kind == LValue)
321    ((LV*)(char*)Data.buffer)->~LV();
322  else if (Kind == Array)
323    ((Arr*)(char*)Data.buffer)->~Arr();
324  else if (Kind == Struct)
325    ((StructData*)(char*)Data.buffer)->~StructData();
326  else if (Kind == Union)
327    ((UnionData*)(char*)Data.buffer)->~UnionData();
328  else if (Kind == MemberPointer)
329    ((MemberPointerData*)(char*)Data.buffer)->~MemberPointerData();
330  else if (Kind == AddrLabelDiff)
331    ((AddrLabelDiffData*)(char*)Data.buffer)->~AddrLabelDiffData();
332  Kind = None;
333}
334
335bool APValue::needsCleanup() const {
336  switch (getKind()) {
337  case None:
338  case Indeterminate:
339  case AddrLabelDiff:
340    return false;
341  case Struct:
342  case Union:
343  case Array:
344  case Vector:
345    return true;
346  case Int:
347    return getInt().needsCleanup();
348  case Float:
349    return getFloat().needsCleanup();
350  case FixedPoint:
351    return getFixedPoint().getValue().needsCleanup();
352  case ComplexFloat:
353    assert(getComplexFloatImag().needsCleanup() ==
354               getComplexFloatReal().needsCleanup() &&
355           "In _Complex float types, real and imaginary values always have the "
356           "same size.");
357    return getComplexFloatReal().needsCleanup();
358  case ComplexInt:
359    assert(getComplexIntImag().needsCleanup() ==
360               getComplexIntReal().needsCleanup() &&
361           "In _Complex int types, real and imaginary values must have the "
362           "same size.");
363    return getComplexIntReal().needsCleanup();
364  case LValue:
365    return reinterpret_cast<const LV *>(Data.buffer)->hasPathPtr();
366  case MemberPointer:
367    return reinterpret_cast<const MemberPointerData *>(Data.buffer)
368        ->hasPathPtr();
369  }
370  llvm_unreachable("Unknown APValue kind!");
371}
372
373void APValue::swap(APValue &RHS) {
374  std::swap(Kind, RHS.Kind);
375  char TmpData[DataSize];
376  memcpy(TmpData, Data.buffer, DataSize);
377  memcpy(Data.buffer, RHS.Data.buffer, DataSize);
378  memcpy(RHS.Data.buffer, TmpData, DataSize);
379}
380
381LLVM_DUMP_METHOD void APValue::dump() const {
382  dump(llvm::errs());
383  llvm::errs() << '\n';
384}
385
386static double GetApproxValue(const llvm::APFloat &F) {
387  llvm::APFloat V = F;
388  bool ignored;
389  V.convert(llvm::APFloat::IEEEdouble(), llvm::APFloat::rmNearestTiesToEven,
390            &ignored);
391  return V.convertToDouble();
392}
393
394void APValue::dump(raw_ostream &OS) const {
395  switch (getKind()) {
396  case None:
397    OS << "None";
398    return;
399  case Indeterminate:
400    OS << "Indeterminate";
401    return;
402  case Int:
403    OS << "Int: " << getInt();
404    return;
405  case Float:
406    OS << "Float: " << GetApproxValue(getFloat());
407    return;
408  case FixedPoint:
409    OS << "FixedPoint : " << getFixedPoint();
410    return;
411  case Vector:
412    OS << "Vector: ";
413    getVectorElt(0).dump(OS);
414    for (unsigned i = 1; i != getVectorLength(); ++i) {
415      OS << ", ";
416      getVectorElt(i).dump(OS);
417    }
418    return;
419  case ComplexInt:
420    OS << "ComplexInt: " << getComplexIntReal() << ", " << getComplexIntImag();
421    return;
422  case ComplexFloat:
423    OS << "ComplexFloat: " << GetApproxValue(getComplexFloatReal())
424       << ", " << GetApproxValue(getComplexFloatImag());
425    return;
426  case LValue:
427    OS << "LValue: <todo>";
428    return;
429  case Array:
430    OS << "Array: ";
431    for (unsigned I = 0, N = getArrayInitializedElts(); I != N; ++I) {
432      getArrayInitializedElt(I).dump(OS);
433      if (I != getArraySize() - 1) OS << ", ";
434    }
435    if (hasArrayFiller()) {
436      OS << getArraySize() - getArrayInitializedElts() << " x ";
437      getArrayFiller().dump(OS);
438    }
439    return;
440  case Struct:
441    OS << "Struct ";
442    if (unsigned N = getStructNumBases()) {
443      OS << " bases: ";
444      getStructBase(0).dump(OS);
445      for (unsigned I = 1; I != N; ++I) {
446        OS << ", ";
447        getStructBase(I).dump(OS);
448      }
449    }
450    if (unsigned N = getStructNumFields()) {
451      OS << " fields: ";
452      getStructField(0).dump(OS);
453      for (unsigned I = 1; I != N; ++I) {
454        OS << ", ";
455        getStructField(I).dump(OS);
456      }
457    }
458    return;
459  case Union:
460    OS << "Union: ";
461    getUnionValue().dump(OS);
462    return;
463  case MemberPointer:
464    OS << "MemberPointer: <todo>";
465    return;
466  case AddrLabelDiff:
467    OS << "AddrLabelDiff: <todo>";
468    return;
469  }
470  llvm_unreachable("Unknown APValue kind!");
471}
472
473void APValue::printPretty(raw_ostream &Out, const ASTContext &Ctx,
474                          QualType Ty) const {
475  switch (getKind()) {
476  case APValue::None:
477    Out << "<out of lifetime>";
478    return;
479  case APValue::Indeterminate:
480    Out << "<uninitialized>";
481    return;
482  case APValue::Int:
483    if (Ty->isBooleanType())
484      Out << (getInt().getBoolValue() ? "true" : "false");
485    else
486      Out << getInt();
487    return;
488  case APValue::Float:
489    Out << GetApproxValue(getFloat());
490    return;
491  case APValue::FixedPoint:
492    Out << getFixedPoint();
493    return;
494  case APValue::Vector: {
495    Out << '{';
496    QualType ElemTy = Ty->castAs<VectorType>()->getElementType();
497    getVectorElt(0).printPretty(Out, Ctx, ElemTy);
498    for (unsigned i = 1; i != getVectorLength(); ++i) {
499      Out << ", ";
500      getVectorElt(i).printPretty(Out, Ctx, ElemTy);
501    }
502    Out << '}';
503    return;
504  }
505  case APValue::ComplexInt:
506    Out << getComplexIntReal() << "+" << getComplexIntImag() << "i";
507    return;
508  case APValue::ComplexFloat:
509    Out << GetApproxValue(getComplexFloatReal()) << "+"
510        << GetApproxValue(getComplexFloatImag()) << "i";
511    return;
512  case APValue::LValue: {
513    bool IsReference = Ty->isReferenceType();
514    QualType InnerTy
515      = IsReference ? Ty.getNonReferenceType() : Ty->getPointeeType();
516    if (InnerTy.isNull())
517      InnerTy = Ty;
518
519    LValueBase Base = getLValueBase();
520    if (!Base) {
521      if (isNullPointer()) {
522        Out << (Ctx.getLangOpts().CPlusPlus11 ? "nullptr" : "0");
523      } else if (IsReference) {
524        Out << "*(" << InnerTy.stream(Ctx.getPrintingPolicy()) << "*)"
525            << getLValueOffset().getQuantity();
526      } else {
527        Out << "(" << Ty.stream(Ctx.getPrintingPolicy()) << ")"
528            << getLValueOffset().getQuantity();
529      }
530      return;
531    }
532
533    if (!hasLValuePath()) {
534      // No lvalue path: just print the offset.
535      CharUnits O = getLValueOffset();
536      CharUnits S = Ctx.getTypeSizeInChars(InnerTy);
537      if (!O.isZero()) {
538        if (IsReference)
539          Out << "*(";
540        if (O % S) {
541          Out << "(char*)";
542          S = CharUnits::One();
543        }
544        Out << '&';
545      } else if (!IsReference) {
546        Out << '&';
547      }
548
549      if (const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>())
550        Out << *VD;
551      else if (TypeInfoLValue TI = Base.dyn_cast<TypeInfoLValue>()) {
552        TI.print(Out, Ctx.getPrintingPolicy());
553      } else if (DynamicAllocLValue DA = Base.dyn_cast<DynamicAllocLValue>()) {
554        Out << "{*new "
555            << Base.getDynamicAllocType().stream(Ctx.getPrintingPolicy()) << "#"
556            << DA.getIndex() << "}";
557      } else {
558        assert(Base.get<const Expr *>() != nullptr &&
559               "Expecting non-null Expr");
560        Base.get<const Expr*>()->printPretty(Out, nullptr,
561                                             Ctx.getPrintingPolicy());
562      }
563
564      if (!O.isZero()) {
565        Out << " + " << (O / S);
566        if (IsReference)
567          Out << ')';
568      }
569      return;
570    }
571
572    // We have an lvalue path. Print it out nicely.
573    if (!IsReference)
574      Out << '&';
575    else if (isLValueOnePastTheEnd())
576      Out << "*(&";
577
578    QualType ElemTy;
579    if (const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>()) {
580      Out << *VD;
581      ElemTy = VD->getType();
582    } else if (TypeInfoLValue TI = Base.dyn_cast<TypeInfoLValue>()) {
583      TI.print(Out, Ctx.getPrintingPolicy());
584      ElemTy = Base.getTypeInfoType();
585    } else if (DynamicAllocLValue DA = Base.dyn_cast<DynamicAllocLValue>()) {
586      Out << "{*new "
587          << Base.getDynamicAllocType().stream(Ctx.getPrintingPolicy()) << "#"
588          << DA.getIndex() << "}";
589      ElemTy = Base.getDynamicAllocType();
590    } else {
591      const Expr *E = Base.get<const Expr*>();
592      assert(E != nullptr && "Expecting non-null Expr");
593      E->printPretty(Out, nullptr, Ctx.getPrintingPolicy());
594      // FIXME: This is wrong if E is a MaterializeTemporaryExpr with an lvalue
595      // adjustment.
596      ElemTy = E->getType();
597    }
598
599    ArrayRef<LValuePathEntry> Path = getLValuePath();
600    const CXXRecordDecl *CastToBase = nullptr;
601    for (unsigned I = 0, N = Path.size(); I != N; ++I) {
602      if (ElemTy->getAs<RecordType>()) {
603        // The lvalue refers to a class type, so the next path entry is a base
604        // or member.
605        const Decl *BaseOrMember = Path[I].getAsBaseOrMember().getPointer();
606        if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(BaseOrMember)) {
607          CastToBase = RD;
608          ElemTy = Ctx.getRecordType(RD);
609        } else {
610          const ValueDecl *VD = cast<ValueDecl>(BaseOrMember);
611          Out << ".";
612          if (CastToBase)
613            Out << *CastToBase << "::";
614          Out << *VD;
615          ElemTy = VD->getType();
616        }
617      } else {
618        // The lvalue must refer to an array.
619        Out << '[' << Path[I].getAsArrayIndex() << ']';
620        ElemTy = Ctx.getAsArrayType(ElemTy)->getElementType();
621      }
622    }
623
624    // Handle formatting of one-past-the-end lvalues.
625    if (isLValueOnePastTheEnd()) {
626      // FIXME: If CastToBase is non-0, we should prefix the output with
627      // "(CastToBase*)".
628      Out << " + 1";
629      if (IsReference)
630        Out << ')';
631    }
632    return;
633  }
634  case APValue::Array: {
635    const ArrayType *AT = Ctx.getAsArrayType(Ty);
636    QualType ElemTy = AT->getElementType();
637    Out << '{';
638    if (unsigned N = getArrayInitializedElts()) {
639      getArrayInitializedElt(0).printPretty(Out, Ctx, ElemTy);
640      for (unsigned I = 1; I != N; ++I) {
641        Out << ", ";
642        if (I == 10) {
643          // Avoid printing out the entire contents of large arrays.
644          Out << "...";
645          break;
646        }
647        getArrayInitializedElt(I).printPretty(Out, Ctx, ElemTy);
648      }
649    }
650    Out << '}';
651    return;
652  }
653  case APValue::Struct: {
654    Out << '{';
655    const RecordDecl *RD = Ty->castAs<RecordType>()->getDecl();
656    bool First = true;
657    if (unsigned N = getStructNumBases()) {
658      const CXXRecordDecl *CD = cast<CXXRecordDecl>(RD);
659      CXXRecordDecl::base_class_const_iterator BI = CD->bases_begin();
660      for (unsigned I = 0; I != N; ++I, ++BI) {
661        assert(BI != CD->bases_end());
662        if (!First)
663          Out << ", ";
664        getStructBase(I).printPretty(Out, Ctx, BI->getType());
665        First = false;
666      }
667    }
668    for (const auto *FI : RD->fields()) {
669      if (!First)
670        Out << ", ";
671      if (FI->isUnnamedBitfield()) continue;
672      getStructField(FI->getFieldIndex()).
673        printPretty(Out, Ctx, FI->getType());
674      First = false;
675    }
676    Out << '}';
677    return;
678  }
679  case APValue::Union:
680    Out << '{';
681    if (const FieldDecl *FD = getUnionField()) {
682      Out << "." << *FD << " = ";
683      getUnionValue().printPretty(Out, Ctx, FD->getType());
684    }
685    Out << '}';
686    return;
687  case APValue::MemberPointer:
688    // FIXME: This is not enough to unambiguously identify the member in a
689    // multiple-inheritance scenario.
690    if (const ValueDecl *VD = getMemberPointerDecl()) {
691      Out << '&' << *cast<CXXRecordDecl>(VD->getDeclContext()) << "::" << *VD;
692      return;
693    }
694    Out << "0";
695    return;
696  case APValue::AddrLabelDiff:
697    Out << "&&" << getAddrLabelDiffLHS()->getLabel()->getName();
698    Out << " - ";
699    Out << "&&" << getAddrLabelDiffRHS()->getLabel()->getName();
700    return;
701  }
702  llvm_unreachable("Unknown APValue kind!");
703}
704
705std::string APValue::getAsString(const ASTContext &Ctx, QualType Ty) const {
706  std::string Result;
707  llvm::raw_string_ostream Out(Result);
708  printPretty(Out, Ctx, Ty);
709  Out.flush();
710  return Result;
711}
712
713bool APValue::toIntegralConstant(APSInt &Result, QualType SrcTy,
714                                 const ASTContext &Ctx) const {
715  if (isInt()) {
716    Result = getInt();
717    return true;
718  }
719
720  if (isLValue() && isNullPointer()) {
721    Result = Ctx.MakeIntValue(Ctx.getTargetNullPointerValue(SrcTy), SrcTy);
722    return true;
723  }
724
725  if (isLValue() && !getLValueBase()) {
726    Result = Ctx.MakeIntValue(getLValueOffset().getQuantity(), SrcTy);
727    return true;
728  }
729
730  return false;
731}
732
733const APValue::LValueBase APValue::getLValueBase() const {
734  assert(isLValue() && "Invalid accessor");
735  return ((const LV*)(const void*)Data.buffer)->Base;
736}
737
738bool APValue::isLValueOnePastTheEnd() const {
739  assert(isLValue() && "Invalid accessor");
740  return ((const LV*)(const void*)Data.buffer)->IsOnePastTheEnd;
741}
742
743CharUnits &APValue::getLValueOffset() {
744  assert(isLValue() && "Invalid accessor");
745  return ((LV*)(void*)Data.buffer)->Offset;
746}
747
748bool APValue::hasLValuePath() const {
749  assert(isLValue() && "Invalid accessor");
750  return ((const LV*)(const char*)Data.buffer)->hasPath();
751}
752
753ArrayRef<APValue::LValuePathEntry> APValue::getLValuePath() const {
754  assert(isLValue() && hasLValuePath() && "Invalid accessor");
755  const LV &LVal = *((const LV*)(const char*)Data.buffer);
756  return llvm::makeArrayRef(LVal.getPath(), LVal.PathLength);
757}
758
759unsigned APValue::getLValueCallIndex() const {
760  assert(isLValue() && "Invalid accessor");
761  return ((const LV*)(const char*)Data.buffer)->Base.getCallIndex();
762}
763
764unsigned APValue::getLValueVersion() const {
765  assert(isLValue() && "Invalid accessor");
766  return ((const LV*)(const char*)Data.buffer)->Base.getVersion();
767}
768
769bool APValue::isNullPointer() const {
770  assert(isLValue() && "Invalid usage");
771  return ((const LV*)(const char*)Data.buffer)->IsNullPtr;
772}
773
774void APValue::setLValue(LValueBase B, const CharUnits &O, NoLValuePath,
775                        bool IsNullPtr) {
776  assert(isLValue() && "Invalid accessor");
777  LV &LVal = *((LV*)(char*)Data.buffer);
778  LVal.Base = B;
779  LVal.IsOnePastTheEnd = false;
780  LVal.Offset = O;
781  LVal.resizePath((unsigned)-1);
782  LVal.IsNullPtr = IsNullPtr;
783}
784
785void APValue::setLValue(LValueBase B, const CharUnits &O,
786                        ArrayRef<LValuePathEntry> Path, bool IsOnePastTheEnd,
787                        bool IsNullPtr) {
788  assert(isLValue() && "Invalid accessor");
789  LV &LVal = *((LV*)(char*)Data.buffer);
790  LVal.Base = B;
791  LVal.IsOnePastTheEnd = IsOnePastTheEnd;
792  LVal.Offset = O;
793  LVal.resizePath(Path.size());
794  memcpy(LVal.getPath(), Path.data(), Path.size() * sizeof(LValuePathEntry));
795  LVal.IsNullPtr = IsNullPtr;
796}
797
798const ValueDecl *APValue::getMemberPointerDecl() const {
799  assert(isMemberPointer() && "Invalid accessor");
800  const MemberPointerData &MPD =
801      *((const MemberPointerData *)(const char *)Data.buffer);
802  return MPD.MemberAndIsDerivedMember.getPointer();
803}
804
805bool APValue::isMemberPointerToDerivedMember() const {
806  assert(isMemberPointer() && "Invalid accessor");
807  const MemberPointerData &MPD =
808      *((const MemberPointerData *)(const char *)Data.buffer);
809  return MPD.MemberAndIsDerivedMember.getInt();
810}
811
812ArrayRef<const CXXRecordDecl*> APValue::getMemberPointerPath() const {
813  assert(isMemberPointer() && "Invalid accessor");
814  const MemberPointerData &MPD =
815      *((const MemberPointerData *)(const char *)Data.buffer);
816  return llvm::makeArrayRef(MPD.getPath(), MPD.PathLength);
817}
818
819void APValue::MakeLValue() {
820  assert(isAbsent() && "Bad state change");
821  static_assert(sizeof(LV) <= DataSize, "LV too big");
822  new ((void*)(char*)Data.buffer) LV();
823  Kind = LValue;
824}
825
826void APValue::MakeArray(unsigned InitElts, unsigned Size) {
827  assert(isAbsent() && "Bad state change");
828  new ((void*)(char*)Data.buffer) Arr(InitElts, Size);
829  Kind = Array;
830}
831
832void APValue::MakeMemberPointer(const ValueDecl *Member, bool IsDerivedMember,
833                                ArrayRef<const CXXRecordDecl*> Path) {
834  assert(isAbsent() && "Bad state change");
835  MemberPointerData *MPD = new ((void*)(char*)Data.buffer) MemberPointerData;
836  Kind = MemberPointer;
837  MPD->MemberAndIsDerivedMember.setPointer(Member);
838  MPD->MemberAndIsDerivedMember.setInt(IsDerivedMember);
839  MPD->resizePath(Path.size());
840  memcpy(MPD->getPath(), Path.data(), Path.size()*sizeof(const CXXRecordDecl*));
841}
842