AnalysisContext.h revision 26c9cb55cb96643c0759c08d037c16c309864087 
1//=== AnalysisContext.h - Analysis context for Path Sens 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 AnalysisContext, a class that manages the analysis context
11// data for path sensitive analysis.
12//
13//===----------------------------------------------------------------------===//
14
15#ifndef LLVM_CLANG_ANALYSIS_ANALYSISCONTEXT_H
16#define LLVM_CLANG_ANALYSIS_ANALYSISCONTEXT_H
17
18#include "clang/AST/Decl.h"
19#include "clang/AST/Expr.h"
20#include "llvm/ADT/OwningPtr.h"
21#include "llvm/ADT/FoldingSet.h"
22#include "llvm/ADT/PointerUnion.h"
23#include "llvm/ADT/DenseMap.h"
24#include "llvm/Support/Allocator.h"
25
26namespace clang {
27
28class Decl;
29class Stmt;
30class CFG;
31class CFGBlock;
32class LiveVariables;
33class ParentMap;
34class PseudoConstantAnalysis;
35class ImplicitParamDecl;
36class LocationContextManager;
37class StackFrameContext;
38
39namespace idx { class TranslationUnit; }
40
41/// AnalysisContext contains the context data for the function or method under
42/// analysis.
43class AnalysisContext {
44  const Decl *D;
45
46  // TranslationUnit is NULL if we don't have multiple translation units.
47  idx::TranslationUnit *TU;
48
49  // AnalysisContext owns the following data.
50  CFG *cfg, *completeCFG;
51  bool builtCFG, builtCompleteCFG;
52  LiveVariables *liveness;
53  LiveVariables *relaxedLiveness;
54  ParentMap *PM;
55  PseudoConstantAnalysis *PCA;
56  llvm::DenseMap<const BlockDecl*,void*> *ReferencedBlockVars;
57  llvm::BumpPtrAllocator A;
58  bool UseUnoptimizedCFG;
59  bool AddEHEdges;
60  bool AddImplicitDtors;
61  bool AddInitializers;
62public:
63  AnalysisContext(const Decl *d, idx::TranslationUnit *tu,
64                  bool useUnoptimizedCFG = false,
65                  bool addehedges = false,
66                  bool addImplicitDtors = false,
67                  bool addInitializers = false)
68    : D(d), TU(tu), cfg(0), completeCFG(0),
69      builtCFG(false), builtCompleteCFG(false),
70      liveness(0), relaxedLiveness(0), PM(0), PCA(0),
71      ReferencedBlockVars(0), UseUnoptimizedCFG(useUnoptimizedCFG),
72      AddEHEdges(addehedges), AddImplicitDtors(addImplicitDtors),
73      AddInitializers(addInitializers) {}
74
75  ~AnalysisContext();
76
77  ASTContext &getASTContext() { return D->getASTContext(); }
78  const Decl *getDecl() const { return D; }
79
80  idx::TranslationUnit *getTranslationUnit() const { return TU; }
81
82  /// getAddEHEdges - Return true iff we are adding exceptional edges from
83  /// callExprs.  If this is false, then try/catch statements and blocks
84  /// reachable from them can appear to be dead in the CFG, analysis passes must
85  /// cope with that.
86  bool getAddEHEdges() const { return AddEHEdges; }
87
88  bool getUseUnoptimizedCFG() const { return UseUnoptimizedCFG; }
89  bool getAddImplicitDtors() const { return AddImplicitDtors; }
90  bool getAddInitializers() const { return AddInitializers; }
91
92  Stmt *getBody();
93  CFG *getCFG();
94
95  /// Return a version of the CFG without any edges pruned.
96  CFG *getUnoptimizedCFG();
97
98  ParentMap &getParentMap();
99  PseudoConstantAnalysis *getPseudoConstantAnalysis();
100  LiveVariables *getLiveVariables();
101  LiveVariables *getRelaxedLiveVariables();
102
103  typedef const VarDecl * const * referenced_decls_iterator;
104
105  std::pair<referenced_decls_iterator, referenced_decls_iterator>
106    getReferencedBlockVars(const BlockDecl *BD);
107
108  /// Return the ImplicitParamDecl* associated with 'self' if this
109  /// AnalysisContext wraps an ObjCMethodDecl.  Returns NULL otherwise.
110  const ImplicitParamDecl *getSelfDecl() const;
111};
112
113class AnalysisContextManager {
114  typedef llvm::DenseMap<const Decl*, AnalysisContext*> ContextMap;
115  ContextMap Contexts;
116  bool UseUnoptimizedCFG;
117  bool AddImplicitDtors;
118  bool AddInitializers;
119public:
120  AnalysisContextManager(bool useUnoptimizedCFG = false,
121      bool addImplicitDtors = false, bool addInitializers = false)
122    : UseUnoptimizedCFG(useUnoptimizedCFG), AddImplicitDtors(addImplicitDtors),
123      AddInitializers(addInitializers) {}
124
125  ~AnalysisContextManager();
126
127  AnalysisContext *getContext(const Decl *D, idx::TranslationUnit *TU = 0);
128
129  bool getUseUnoptimizedCFG() const { return UseUnoptimizedCFG; }
130  bool getAddImplicitDtors() const { return AddImplicitDtors; }
131  bool getAddInitializers() const { return AddInitializers; }
132
133  // Discard all previously created AnalysisContexts.
134  void clear();
135};
136
137class LocationContext : public llvm::FoldingSetNode {
138public:
139  enum ContextKind { StackFrame, Scope, Block };
140
141private:
142  ContextKind Kind;
143
144  // AnalysisContext can't be const since some methods may modify its member.
145  AnalysisContext *Ctx;
146
147  const LocationContext *Parent;
148
149protected:
150  LocationContext(ContextKind k, AnalysisContext *ctx,
151                  const LocationContext *parent)
152    : Kind(k), Ctx(ctx), Parent(parent) {}
153
154public:
155  virtual ~LocationContext();
156
157  ContextKind getKind() const { return Kind; }
158
159  AnalysisContext *getAnalysisContext() const { return Ctx; }
160
161  idx::TranslationUnit *getTranslationUnit() const {
162    return Ctx->getTranslationUnit();
163  }
164
165  const LocationContext *getParent() const { return Parent; }
166
167  bool isParentOf(const LocationContext *LC) const;
168
169  const Decl *getDecl() const { return getAnalysisContext()->getDecl(); }
170
171  CFG *getCFG() const { return getAnalysisContext()->getCFG(); }
172
173  LiveVariables *getLiveVariables() const {
174    return getAnalysisContext()->getLiveVariables();
175  }
176
177  ParentMap &getParentMap() const {
178    return getAnalysisContext()->getParentMap();
179  }
180
181  const ImplicitParamDecl *getSelfDecl() const {
182    return Ctx->getSelfDecl();
183  }
184
185  const StackFrameContext *getCurrentStackFrame() const;
186  const StackFrameContext *
187    getStackFrameForDeclContext(const DeclContext *DC) const;
188
189  virtual void Profile(llvm::FoldingSetNodeID &ID) = 0;
190
191  static bool classof(const LocationContext*) { return true; }
192
193public:
194  static void ProfileCommon(llvm::FoldingSetNodeID &ID,
195                            ContextKind ck,
196                            AnalysisContext *ctx,
197                            const LocationContext *parent,
198                            const void* data);
199};
200
201class StackFrameContext : public LocationContext {
202  // The callsite where this stack frame is established.
203  const Stmt *CallSite;
204
205  // The parent block of the callsite.
206  const CFGBlock *Block;
207
208  // The index of the callsite in the CFGBlock.
209  unsigned Index;
210
211  friend class LocationContextManager;
212  StackFrameContext(AnalysisContext *ctx, const LocationContext *parent,
213                    const Stmt *s, const CFGBlock *blk,
214                    unsigned idx)
215    : LocationContext(StackFrame, ctx, parent), CallSite(s),
216      Block(blk), Index(idx) {}
217
218public:
219  ~StackFrameContext() {}
220
221  const Stmt *getCallSite() const { return CallSite; }
222
223  const CFGBlock *getCallSiteBlock() const { return Block; }
224
225  unsigned getIndex() const { return Index; }
226
227  void Profile(llvm::FoldingSetNodeID &ID);
228
229  static void Profile(llvm::FoldingSetNodeID &ID, AnalysisContext *ctx,
230                      const LocationContext *parent, const Stmt *s,
231                      const CFGBlock *blk, unsigned idx) {
232    ProfileCommon(ID, StackFrame, ctx, parent, s);
233    ID.AddPointer(blk);
234    ID.AddInteger(idx);
235  }
236
237  static bool classof(const LocationContext* Ctx) {
238    return Ctx->getKind() == StackFrame;
239  }
240};
241
242class ScopeContext : public LocationContext {
243  const Stmt *Enter;
244
245  friend class LocationContextManager;
246  ScopeContext(AnalysisContext *ctx, const LocationContext *parent,
247               const Stmt *s)
248    : LocationContext(Scope, ctx, parent), Enter(s) {}
249
250public:
251  ~ScopeContext() {}
252
253  void Profile(llvm::FoldingSetNodeID &ID);
254
255  static void Profile(llvm::FoldingSetNodeID &ID, AnalysisContext *ctx,
256                      const LocationContext *parent, const Stmt *s) {
257    ProfileCommon(ID, Scope, ctx, parent, s);
258  }
259
260  static bool classof(const LocationContext* Ctx) {
261    return Ctx->getKind() == Scope;
262  }
263};
264
265class BlockInvocationContext : public LocationContext {
266  // FIXME: Add back context-sensivity (we don't want libAnalysis to know
267  //  about MemRegion).
268  const BlockDecl *BD;
269
270  friend class LocationContextManager;
271
272  BlockInvocationContext(AnalysisContext *ctx, const LocationContext *parent,
273                         const BlockDecl *bd)
274    : LocationContext(Block, ctx, parent), BD(bd) {}
275
276public:
277  ~BlockInvocationContext() {}
278
279  const BlockDecl *getBlockDecl() const { return BD; }
280
281  void Profile(llvm::FoldingSetNodeID &ID);
282
283  static void Profile(llvm::FoldingSetNodeID &ID, AnalysisContext *ctx,
284                      const LocationContext *parent, const BlockDecl *bd) {
285    ProfileCommon(ID, Block, ctx, parent, bd);
286  }
287
288  static bool classof(const LocationContext* Ctx) {
289    return Ctx->getKind() == Block;
290  }
291};
292
293class LocationContextManager {
294  llvm::FoldingSet<LocationContext> Contexts;
295public:
296  ~LocationContextManager();
297
298  const StackFrameContext *getStackFrame(AnalysisContext *ctx,
299                                         const LocationContext *parent,
300                                         const Stmt *s,
301                                         const CFGBlock *blk, unsigned idx);
302
303  const ScopeContext *getScope(AnalysisContext *ctx,
304                               const LocationContext *parent,
305                               const Stmt *s);
306
307  /// Discard all previously created LocationContext objects.
308  void clear();
309private:
310  template <typename LOC, typename DATA>
311  const LOC *getLocationContext(AnalysisContext *ctx,
312                                const LocationContext *parent,
313                                const DATA *d);
314};
315
316} // end clang namespace
317#endif
318