ProgramPoint.h revision e8063ae53bd241de10ba1053054d06867a5c56ab 
1//==- ProgramPoint.h - Program Points for Path-Sensitive Analysis --*- 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 interface ProgramPoint, which identifies a
11//  distinct location in a function.
12//
13//===----------------------------------------------------------------------===//
14
15#ifndef LLVM_CLANG_ANALYSIS_PROGRAM_POINT
16#define LLVM_CLANG_ANALYSIS_PROGRAM_POINT
17
18#include "clang/AST/CFG.h"
19#include "llvm/Support/DataTypes.h"
20#include "llvm/ADT/DenseMap.h"
21#include "llvm/ADT/FoldingSet.h"
22#include <cassert>
23#include <utility>
24
25namespace clang {
26
27class ProgramPoint {
28public:
29  enum Kind { BlockEdgeKind = 0x0,
30              BlockEntranceKind = 0x1,
31              BlockExitKind = 0x2,
32              // Keep the following four together and in this order.
33              PostStmtKind = 0x3,
34              PostLocationChecksSucceedKind = 0x4,
35              PostOutOfBoundsCheckFailedKind = 0x5,
36              PostNullCheckFailedKind = 0x6,
37              PostUndefLocationCheckFailedKind = 0x7,
38              PostLoadKind = 0x8,
39              PostStoreKind = 0x9,
40              PostPurgeDeadSymbolsKind = 0x10,
41              PostStmtCustomKind = 0x11,
42              MinPostStmtKind = PostStmtKind,
43              MaxPostStmtKind = PostStmtCustomKind };
44
45private:
46  enum { TwoPointers = 0x1, Custom = 0x2, Mask = 0x3 };
47
48  std::pair<uintptr_t,uintptr_t> Data;
49  const void *Tag;
50
51protected:
52  ProgramPoint(const void* P, Kind k, const void *tag = 0)
53    : Data(reinterpret_cast<uintptr_t>(P),
54           (uintptr_t) k), Tag(tag) {}
55
56  ProgramPoint(const void* P1, const void* P2, const void *tag = 0)
57    : Data(reinterpret_cast<uintptr_t>(P1) | TwoPointers,
58           reinterpret_cast<uintptr_t>(P2)), Tag(tag) {}
59
60  ProgramPoint(const void* P1, const void* P2, bool)
61    : Data(reinterpret_cast<uintptr_t>(P1) | Custom,
62           reinterpret_cast<uintptr_t>(P2)), Tag(0) {}
63
64protected:
65  void* getData1NoMask() const {
66    Kind k = getKind(); k = k;
67    assert(k == BlockEntranceKind || k == BlockExitKind);
68    return reinterpret_cast<void*>(Data.first);
69  }
70
71  void* getData1() const {
72    Kind k = getKind(); k = k;
73    assert(k == BlockEdgeKind ||(k >= MinPostStmtKind && k <= MaxPostStmtKind));
74    return reinterpret_cast<void*>(Data.first & ~Mask);
75  }
76
77  void* getData2() const {
78    Kind k = getKind(); k = k;
79    assert(k == BlockEdgeKind || k == PostStmtCustomKind);
80    return reinterpret_cast<void*>(Data.second);
81  }
82
83  const void *getTag() const { return Tag; }
84
85public:
86  Kind getKind() const {
87    switch (Data.first & Mask) {
88      case TwoPointers: return BlockEdgeKind;
89      case Custom: return PostStmtCustomKind;
90      default: return (Kind) Data.second;
91    }
92  }
93
94  // For use with DenseMap.  This hash is probably slow.
95  unsigned getHashValue() const {
96    llvm::FoldingSetNodeID ID;
97    ID.AddPointer(reinterpret_cast<void*>(Data.first));
98    ID.AddPointer(reinterpret_cast<void*>(Data.second));
99    ID.AddPointer(Tag);
100    return ID.ComputeHash();
101  }
102
103  static bool classof(const ProgramPoint*) { return true; }
104
105  bool operator==(const ProgramPoint & RHS) const {
106    return Data == RHS.Data && Tag == RHS.Tag;
107  }
108
109  bool operator!=(const ProgramPoint& RHS) const {
110    return Data != RHS.Data || Tag != RHS.Tag;
111  }
112
113  bool operator<(const ProgramPoint& RHS) const {
114    return Data < RHS.Data && Tag < RHS.Tag;
115  }
116
117  void Profile(llvm::FoldingSetNodeID& ID) const {
118    ID.AddPointer(reinterpret_cast<void*>(Data.first));
119    if (getKind() != PostStmtCustomKind)
120      ID.AddPointer(reinterpret_cast<void*>(Data.second));
121    else {
122      const std::pair<const void*, const void*> *P =
123        reinterpret_cast<std::pair<const void*, const void*>*>(Data.second);
124      ID.AddPointer(P->first);
125      ID.AddPointer(P->second);
126    }
127    ID.AddPointer(Tag);
128  }
129};
130
131class BlockEntrance : public ProgramPoint {
132public:
133  BlockEntrance(const CFGBlock* B) : ProgramPoint(B, BlockEntranceKind) {}
134
135  CFGBlock* getBlock() const {
136    return reinterpret_cast<CFGBlock*>(getData1NoMask());
137  }
138
139  Stmt* getFirstStmt() const {
140    CFGBlock* B = getBlock();
141    return B->empty() ? NULL : B->front();
142  }
143
144  static bool classof(const ProgramPoint* Location) {
145    return Location->getKind() == BlockEntranceKind;
146  }
147};
148
149class BlockExit : public ProgramPoint {
150public:
151  BlockExit(const CFGBlock* B) : ProgramPoint(B, BlockExitKind) {}
152
153  CFGBlock* getBlock() const {
154    return reinterpret_cast<CFGBlock*>(getData1NoMask());
155  }
156
157  Stmt* getLastStmt() const {
158    CFGBlock* B = getBlock();
159    return B->empty() ? NULL : B->back();
160  }
161
162  Stmt* getTerminator() const {
163    return getBlock()->getTerminator();
164  }
165
166  static bool classof(const ProgramPoint* Location) {
167    return Location->getKind() == BlockExitKind;
168  }
169};
170
171class PostStmt : public ProgramPoint {
172protected:
173  PostStmt(const Stmt* S, Kind k,const void *tag = 0)
174    : ProgramPoint(S, k, tag) {}
175
176  PostStmt(const Stmt* S, const void* data) : ProgramPoint(S, data, true) {}
177
178public:
179  PostStmt(const Stmt* S) : ProgramPoint(S, PostStmtKind) {}
180
181  Stmt* getStmt() const { return (Stmt*) getData1(); }
182
183  static bool classof(const ProgramPoint* Location) {
184    unsigned k = Location->getKind();
185    return k >= MinPostStmtKind && k <= MaxPostStmtKind;
186  }
187};
188
189class PostLocationChecksSucceed : public PostStmt {
190public:
191  PostLocationChecksSucceed(const Stmt* S, const void *tag = 0)
192    : PostStmt(S, PostLocationChecksSucceedKind, tag) {}
193
194  static bool classof(const ProgramPoint* Location) {
195    return Location->getKind() == PostLocationChecksSucceedKind;
196  }
197};
198
199class PostStmtCustom : public PostStmt {
200public:
201  PostStmtCustom(const Stmt* S,
202                 const std::pair<const void*, const void*>* TaggedData)
203    : PostStmt(S, TaggedData) {
204    assert(getKind() == PostStmtCustomKind);
205  }
206
207  const std::pair<const void*, const void*>& getTaggedPair() const {
208    return *reinterpret_cast<std::pair<const void*, const void*>*>(getData2());
209  }
210
211  const void* getTag() const { return getTaggedPair().first; }
212
213  const void* getTaggedData() const { return getTaggedPair().second; }
214
215  static bool classof(const ProgramPoint* Location) {
216    return Location->getKind() == PostStmtCustomKind;
217  }
218};
219
220class PostOutOfBoundsCheckFailed : public PostStmt {
221public:
222  PostOutOfBoundsCheckFailed(const Stmt* S)
223  : PostStmt(S, PostOutOfBoundsCheckFailedKind) {}
224
225  static bool classof(const ProgramPoint* Location) {
226    return Location->getKind() == PostOutOfBoundsCheckFailedKind;
227  }
228};
229
230class PostUndefLocationCheckFailed : public PostStmt {
231public:
232  PostUndefLocationCheckFailed(const Stmt* S)
233  : PostStmt(S, PostUndefLocationCheckFailedKind) {}
234
235  static bool classof(const ProgramPoint* Location) {
236    return Location->getKind() == PostUndefLocationCheckFailedKind;
237  }
238};
239
240class PostNullCheckFailed : public PostStmt {
241public:
242  PostNullCheckFailed(const Stmt* S)
243  : PostStmt(S, PostNullCheckFailedKind) {}
244
245  static bool classof(const ProgramPoint* Location) {
246    return Location->getKind() == PostNullCheckFailedKind;
247  }
248};
249
250class PostLoad : public PostStmt {
251public:
252  PostLoad(const Stmt* S, const void *tag = 0)
253    : PostStmt(S, PostLoadKind, tag) {}
254
255  static bool classof(const ProgramPoint* Location) {
256    return Location->getKind() == PostLoadKind;
257  }
258};
259
260class PostStore : public PostStmt {
261public:
262  PostStore(const Stmt* S, const void *tag = 0)
263    : PostStmt(S, PostStoreKind, tag) {}
264
265  static bool classof(const ProgramPoint* Location) {
266    return Location->getKind() == PostStoreKind;
267  }
268};
269
270class PostPurgeDeadSymbols : public PostStmt {
271public:
272  PostPurgeDeadSymbols(const Stmt* S) : PostStmt(S, PostPurgeDeadSymbolsKind) {}
273
274  static bool classof(const ProgramPoint* Location) {
275    return Location->getKind() == PostPurgeDeadSymbolsKind;
276  }
277};
278
279class BlockEdge : public ProgramPoint {
280public:
281  BlockEdge(const CFGBlock* B1, const CFGBlock* B2)
282    : ProgramPoint(B1, B2) {}
283
284  CFGBlock* getSrc() const {
285    return static_cast<CFGBlock*>(getData1());
286  }
287
288  CFGBlock* getDst() const {
289    return static_cast<CFGBlock*>(getData2());
290  }
291
292  static bool classof(const ProgramPoint* Location) {
293    return Location->getKind() == BlockEdgeKind;
294  }
295};
296
297
298} // end namespace clang
299
300
301namespace llvm { // Traits specialization for DenseMap
302
303template <> struct DenseMapInfo<clang::ProgramPoint> {
304
305static inline clang::ProgramPoint getEmptyKey() {
306  uintptr_t x =
307   reinterpret_cast<uintptr_t>(DenseMapInfo<void*>::getEmptyKey()) & ~0x7;
308  return clang::BlockEntrance(reinterpret_cast<clang::CFGBlock*>(x));
309}
310
311static inline clang::ProgramPoint getTombstoneKey() {
312  uintptr_t x =
313   reinterpret_cast<uintptr_t>(DenseMapInfo<void*>::getTombstoneKey()) & ~0x7;
314  return clang::BlockEntrance(reinterpret_cast<clang::CFGBlock*>(x));
315}
316
317static unsigned getHashValue(const clang::ProgramPoint& Loc) {
318  return Loc.getHashValue();
319}
320
321static bool isEqual(const clang::ProgramPoint& L,
322                    const clang::ProgramPoint& R) {
323  return L == R;
324}
325
326static bool isPod() {
327  return true;
328}
329};
330} // end namespace llvm
331
332#endif
333