APValue.h revision f0f353b36f173ea282209070fcdbbedab84c19db 
1//===--- APValue.h - Union class for APFloat/APSInt/Complex -----*- 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 the APValue class.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_CLANG_AST_APVALUE_H
15#define LLVM_CLANG_AST_APVALUE_H
16
17#include "clang/Basic/LLVM.h"
18#include "llvm/ADT/APFloat.h"
19#include "llvm/ADT/APSInt.h"
20#include "llvm/ADT/PointerIntPair.h"
21#include "llvm/ADT/PointerUnion.h"
22
23namespace clang {
24  class AddrLabelExpr;
25  class ASTContext;
26  class CharUnits;
27  class DiagnosticBuilder;
28  class Expr;
29  class FieldDecl;
30  class Decl;
31  class ValueDecl;
32  class CXXRecordDecl;
33  class QualType;
34
35/// APValue - This class implements a discriminated union of [uninitialized]
36/// [APSInt] [APFloat], [Complex APSInt] [Complex APFloat], [Expr + Offset],
37/// [Vector: N * APValue], [Array: N * APValue]
38class APValue {
39  typedef llvm::APSInt APSInt;
40  typedef llvm::APFloat APFloat;
41public:
42  enum ValueKind {
43    Uninitialized,
44    Int,
45    Float,
46    ComplexInt,
47    ComplexFloat,
48    LValue,
49    Vector,
50    Array,
51    Struct,
52    Union,
53    MemberPointer,
54    AddrLabelDiff
55  };
56  typedef llvm::PointerUnion<const ValueDecl *, const Expr *> LValueBase;
57  typedef llvm::PointerIntPair<const Decl *, 1, bool> BaseOrMemberType;
58  union LValuePathEntry {
59    /// BaseOrMember - The FieldDecl or CXXRecordDecl indicating the next item
60    /// in the path. An opaque value of type BaseOrMemberType.
61    void *BaseOrMember;
62    /// ArrayIndex - The array index of the next item in the path.
63    uint64_t ArrayIndex;
64  };
65  struct NoLValuePath {};
66  struct UninitArray {};
67  struct UninitStruct {};
68private:
69  ValueKind Kind;
70
71  struct ComplexAPSInt {
72    APSInt Real, Imag;
73    ComplexAPSInt() : Real(1), Imag(1) {}
74  };
75  struct ComplexAPFloat {
76    APFloat Real, Imag;
77    ComplexAPFloat() : Real(0.0), Imag(0.0) {}
78  };
79  struct LV;
80  struct Vec {
81    APValue *Elts;
82    unsigned NumElts;
83    Vec() : Elts(0), NumElts(0) {}
84    ~Vec() { delete[] Elts; }
85  };
86  struct Arr {
87    APValue *Elts;
88    unsigned NumElts, ArrSize;
89    Arr(unsigned NumElts, unsigned ArrSize);
90    ~Arr();
91  };
92  struct StructData {
93    APValue *Elts;
94    unsigned NumBases;
95    unsigned NumFields;
96    StructData(unsigned NumBases, unsigned NumFields);
97    ~StructData();
98  };
99  struct UnionData {
100    const FieldDecl *Field;
101    APValue *Value;
102    UnionData();
103    ~UnionData();
104  };
105  struct AddrLabelDiffData {
106    const AddrLabelExpr* LHSExpr;
107    const AddrLabelExpr* RHSExpr;
108  };
109  struct MemberPointerData;
110
111  enum {
112    MaxSize = (sizeof(ComplexAPSInt) > sizeof(ComplexAPFloat) ?
113               sizeof(ComplexAPSInt) : sizeof(ComplexAPFloat))
114  };
115
116  union {
117    void *Aligner;
118    char Data[MaxSize];
119  };
120
121public:
122  APValue() : Kind(Uninitialized) {}
123  explicit APValue(const APSInt &I) : Kind(Uninitialized) {
124    MakeInt(); setInt(I);
125  }
126  explicit APValue(const APFloat &F) : Kind(Uninitialized) {
127    MakeFloat(); setFloat(F);
128  }
129  explicit APValue(const APValue *E, unsigned N) : Kind(Uninitialized) {
130    MakeVector(); setVector(E, N);
131  }
132  APValue(const APSInt &R, const APSInt &I) : Kind(Uninitialized) {
133    MakeComplexInt(); setComplexInt(R, I);
134  }
135  APValue(const APFloat &R, const APFloat &I) : Kind(Uninitialized) {
136    MakeComplexFloat(); setComplexFloat(R, I);
137  }
138  APValue(const APValue &RHS);
139  APValue(LValueBase B, const CharUnits &O, NoLValuePath N, unsigned CallIndex)
140      : Kind(Uninitialized) {
141    MakeLValue(); setLValue(B, O, N, CallIndex);
142  }
143  APValue(LValueBase B, const CharUnits &O, ArrayRef<LValuePathEntry> Path,
144          bool OnePastTheEnd, unsigned CallIndex)
145      : Kind(Uninitialized) {
146    MakeLValue(); setLValue(B, O, Path, OnePastTheEnd, CallIndex);
147  }
148  APValue(UninitArray, unsigned InitElts, unsigned Size) : Kind(Uninitialized) {
149    MakeArray(InitElts, Size);
150  }
151  APValue(UninitStruct, unsigned B, unsigned M) : Kind(Uninitialized) {
152    MakeStruct(B, M);
153  }
154  explicit APValue(const FieldDecl *D, const APValue &V = APValue())
155      : Kind(Uninitialized) {
156    MakeUnion(); setUnion(D, V);
157  }
158  APValue(const ValueDecl *Member, bool IsDerivedMember,
159          ArrayRef<const CXXRecordDecl*> Path) : Kind(Uninitialized) {
160    MakeMemberPointer(Member, IsDerivedMember, Path);
161  }
162  APValue(const AddrLabelExpr* LHSExpr, const AddrLabelExpr* RHSExpr)
163      : Kind(Uninitialized) {
164    MakeAddrLabelDiff(); setAddrLabelDiff(LHSExpr, RHSExpr);
165  }
166
167  ~APValue() {
168    MakeUninit();
169  }
170
171  /// \brief Returns whether the object performed allocations.
172  ///
173  /// If APValues are constructed via placement new, \c needsCleanup()
174  /// indicates whether the destructor must be called in order to correctly
175  /// free all allocated memory.
176  bool needsCleanup() const;
177
178  /// \brief Swaps the contents of this and the given APValue.
179  void swap(APValue &RHS);
180
181  ValueKind getKind() const { return Kind; }
182  bool isUninit() const { return Kind == Uninitialized; }
183  bool isInt() const { return Kind == Int; }
184  bool isFloat() const { return Kind == Float; }
185  bool isComplexInt() const { return Kind == ComplexInt; }
186  bool isComplexFloat() const { return Kind == ComplexFloat; }
187  bool isLValue() const { return Kind == LValue; }
188  bool isVector() const { return Kind == Vector; }
189  bool isArray() const { return Kind == Array; }
190  bool isStruct() const { return Kind == Struct; }
191  bool isUnion() const { return Kind == Union; }
192  bool isMemberPointer() const { return Kind == MemberPointer; }
193  bool isAddrLabelDiff() const { return Kind == AddrLabelDiff; }
194
195  void dump() const;
196  void dump(raw_ostream &OS) const;
197
198  void printPretty(raw_ostream &OS, ASTContext &Ctx, QualType Ty) const;
199  std::string getAsString(ASTContext &Ctx, QualType Ty) const;
200
201  APSInt &getInt() {
202    assert(isInt() && "Invalid accessor");
203    return *(APSInt*)(char*)Data;
204  }
205  const APSInt &getInt() const {
206    return const_cast<APValue*>(this)->getInt();
207  }
208
209  APFloat &getFloat() {
210    assert(isFloat() && "Invalid accessor");
211    return *(APFloat*)(char*)Data;
212  }
213  const APFloat &getFloat() const {
214    return const_cast<APValue*>(this)->getFloat();
215  }
216
217  APSInt &getComplexIntReal() {
218    assert(isComplexInt() && "Invalid accessor");
219    return ((ComplexAPSInt*)(char*)Data)->Real;
220  }
221  const APSInt &getComplexIntReal() const {
222    return const_cast<APValue*>(this)->getComplexIntReal();
223  }
224
225  APSInt &getComplexIntImag() {
226    assert(isComplexInt() && "Invalid accessor");
227    return ((ComplexAPSInt*)(char*)Data)->Imag;
228  }
229  const APSInt &getComplexIntImag() const {
230    return const_cast<APValue*>(this)->getComplexIntImag();
231  }
232
233  APFloat &getComplexFloatReal() {
234    assert(isComplexFloat() && "Invalid accessor");
235    return ((ComplexAPFloat*)(char*)Data)->Real;
236  }
237  const APFloat &getComplexFloatReal() const {
238    return const_cast<APValue*>(this)->getComplexFloatReal();
239  }
240
241  APFloat &getComplexFloatImag() {
242    assert(isComplexFloat() && "Invalid accessor");
243    return ((ComplexAPFloat*)(char*)Data)->Imag;
244  }
245  const APFloat &getComplexFloatImag() const {
246    return const_cast<APValue*>(this)->getComplexFloatImag();
247  }
248
249  const LValueBase getLValueBase() const;
250  CharUnits &getLValueOffset();
251  const CharUnits &getLValueOffset() const {
252    return const_cast<APValue*>(this)->getLValueOffset();
253  }
254  bool isLValueOnePastTheEnd() const;
255  bool hasLValuePath() const;
256  ArrayRef<LValuePathEntry> getLValuePath() const;
257  unsigned getLValueCallIndex() const;
258
259  APValue &getVectorElt(unsigned I) {
260    assert(isVector() && "Invalid accessor");
261    assert(I < getVectorLength() && "Index out of range");
262    return ((Vec*)(char*)Data)->Elts[I];
263  }
264  const APValue &getVectorElt(unsigned I) const {
265    return const_cast<APValue*>(this)->getVectorElt(I);
266  }
267  unsigned getVectorLength() const {
268    assert(isVector() && "Invalid accessor");
269    return ((const Vec*)(const void *)Data)->NumElts;
270  }
271
272  APValue &getArrayInitializedElt(unsigned I) {
273    assert(isArray() && "Invalid accessor");
274    assert(I < getArrayInitializedElts() && "Index out of range");
275    return ((Arr*)(char*)Data)->Elts[I];
276  }
277  const APValue &getArrayInitializedElt(unsigned I) const {
278    return const_cast<APValue*>(this)->getArrayInitializedElt(I);
279  }
280  bool hasArrayFiller() const {
281    return getArrayInitializedElts() != getArraySize();
282  }
283  APValue &getArrayFiller() {
284    assert(isArray() && "Invalid accessor");
285    assert(hasArrayFiller() && "No array filler");
286    return ((Arr*)(char*)Data)->Elts[getArrayInitializedElts()];
287  }
288  const APValue &getArrayFiller() const {
289    return const_cast<APValue*>(this)->getArrayFiller();
290  }
291  unsigned getArrayInitializedElts() const {
292    assert(isArray() && "Invalid accessor");
293    return ((const Arr*)(const void *)Data)->NumElts;
294  }
295  unsigned getArraySize() const {
296    assert(isArray() && "Invalid accessor");
297    return ((const Arr*)(const void *)Data)->ArrSize;
298  }
299
300  unsigned getStructNumBases() const {
301    assert(isStruct() && "Invalid accessor");
302    return ((const StructData*)(const char*)Data)->NumBases;
303  }
304  unsigned getStructNumFields() const {
305    assert(isStruct() && "Invalid accessor");
306    return ((const StructData*)(const char*)Data)->NumFields;
307  }
308  APValue &getStructBase(unsigned i) {
309    assert(isStruct() && "Invalid accessor");
310    return ((StructData*)(char*)Data)->Elts[i];
311  }
312  APValue &getStructField(unsigned i) {
313    assert(isStruct() && "Invalid accessor");
314    return ((StructData*)(char*)Data)->Elts[getStructNumBases() + i];
315  }
316  const APValue &getStructBase(unsigned i) const {
317    return const_cast<APValue*>(this)->getStructBase(i);
318  }
319  const APValue &getStructField(unsigned i) const {
320    return const_cast<APValue*>(this)->getStructField(i);
321  }
322
323  const FieldDecl *getUnionField() const {
324    assert(isUnion() && "Invalid accessor");
325    return ((const UnionData*)(const char*)Data)->Field;
326  }
327  APValue &getUnionValue() {
328    assert(isUnion() && "Invalid accessor");
329    return *((UnionData*)(char*)Data)->Value;
330  }
331  const APValue &getUnionValue() const {
332    return const_cast<APValue*>(this)->getUnionValue();
333  }
334
335  const ValueDecl *getMemberPointerDecl() const;
336  bool isMemberPointerToDerivedMember() const;
337  ArrayRef<const CXXRecordDecl*> getMemberPointerPath() const;
338
339  const AddrLabelExpr* getAddrLabelDiffLHS() const {
340    assert(isAddrLabelDiff() && "Invalid accessor");
341    return ((const AddrLabelDiffData*)(const char*)Data)->LHSExpr;
342  }
343  const AddrLabelExpr* getAddrLabelDiffRHS() const {
344    assert(isAddrLabelDiff() && "Invalid accessor");
345    return ((const AddrLabelDiffData*)(const char*)Data)->RHSExpr;
346  }
347
348  void setInt(const APSInt &I) {
349    assert(isInt() && "Invalid accessor");
350    *(APSInt*)(char*)Data = I;
351  }
352  void setFloat(const APFloat &F) {
353    assert(isFloat() && "Invalid accessor");
354    *(APFloat*)(char*)Data = F;
355  }
356  void setVector(const APValue *E, unsigned N) {
357    assert(isVector() && "Invalid accessor");
358    ((Vec*)(char*)Data)->Elts = new APValue[N];
359    ((Vec*)(char*)Data)->NumElts = N;
360    for (unsigned i = 0; i != N; ++i)
361      ((Vec*)(char*)Data)->Elts[i] = E[i];
362  }
363  void setComplexInt(const APSInt &R, const APSInt &I) {
364    assert(R.getBitWidth() == I.getBitWidth() &&
365           "Invalid complex int (type mismatch).");
366    assert(isComplexInt() && "Invalid accessor");
367    ((ComplexAPSInt*)(char*)Data)->Real = R;
368    ((ComplexAPSInt*)(char*)Data)->Imag = I;
369  }
370  void setComplexFloat(const APFloat &R, const APFloat &I) {
371    assert(&R.getSemantics() == &I.getSemantics() &&
372           "Invalid complex float (type mismatch).");
373    assert(isComplexFloat() && "Invalid accessor");
374    ((ComplexAPFloat*)(char*)Data)->Real = R;
375    ((ComplexAPFloat*)(char*)Data)->Imag = I;
376  }
377  void setLValue(LValueBase B, const CharUnits &O, NoLValuePath,
378                 unsigned CallIndex);
379  void setLValue(LValueBase B, const CharUnits &O,
380                 ArrayRef<LValuePathEntry> Path, bool OnePastTheEnd,
381                 unsigned CallIndex);
382  void setUnion(const FieldDecl *Field, const APValue &Value) {
383    assert(isUnion() && "Invalid accessor");
384    ((UnionData*)(char*)Data)->Field = Field;
385    *((UnionData*)(char*)Data)->Value = Value;
386  }
387  void setAddrLabelDiff(const AddrLabelExpr* LHSExpr,
388                        const AddrLabelExpr* RHSExpr) {
389    ((AddrLabelDiffData*)(char*)Data)->LHSExpr = LHSExpr;
390    ((AddrLabelDiffData*)(char*)Data)->RHSExpr = RHSExpr;
391  }
392
393  /// Assign by swapping from a copy of the RHS.
394  APValue &operator=(APValue RHS) {
395    swap(RHS);
396    return *this;
397  }
398
399private:
400  void DestroyDataAndMakeUninit();
401  void MakeUninit() {
402    if (Kind != Uninitialized)
403      DestroyDataAndMakeUninit();
404  }
405  void MakeInt() {
406    assert(isUninit() && "Bad state change");
407    new ((void*)Data) APSInt(1);
408    Kind = Int;
409  }
410  void MakeFloat() {
411    assert(isUninit() && "Bad state change");
412    new ((void*)(char*)Data) APFloat(0.0);
413    Kind = Float;
414  }
415  void MakeVector() {
416    assert(isUninit() && "Bad state change");
417    new ((void*)(char*)Data) Vec();
418    Kind = Vector;
419  }
420  void MakeComplexInt() {
421    assert(isUninit() && "Bad state change");
422    new ((void*)(char*)Data) ComplexAPSInt();
423    Kind = ComplexInt;
424  }
425  void MakeComplexFloat() {
426    assert(isUninit() && "Bad state change");
427    new ((void*)(char*)Data) ComplexAPFloat();
428    Kind = ComplexFloat;
429  }
430  void MakeLValue();
431  void MakeArray(unsigned InitElts, unsigned Size);
432  void MakeStruct(unsigned B, unsigned M) {
433    assert(isUninit() && "Bad state change");
434    new ((void*)(char*)Data) StructData(B, M);
435    Kind = Struct;
436  }
437  void MakeUnion() {
438    assert(isUninit() && "Bad state change");
439    new ((void*)(char*)Data) UnionData();
440    Kind = Union;
441  }
442  void MakeMemberPointer(const ValueDecl *Member, bool IsDerivedMember,
443                         ArrayRef<const CXXRecordDecl*> Path);
444  void MakeAddrLabelDiff() {
445    assert(isUninit() && "Bad state change");
446    new ((void*)(char*)Data) AddrLabelDiffData();
447    Kind = AddrLabelDiff;
448  }
449};
450
451} // end namespace clang.
452
453#endif
454