1 //== AnalysisContext.cpp - Analysis context for Path Sens analysis -*- C++ -*-//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines AnalysisContext, a class that manages the analysis context
11 // data for path sensitive analysis.
13 //===----------------------------------------------------------------------===//
15 #include "clang/AST/Decl.h"
16 #include "clang/AST/DeclObjC.h"
17 #include "clang/AST/DeclTemplate.h"
18 #include "clang/AST/ParentMap.h"
19 #include "clang/AST/StmtVisitor.h"
20 #include "clang/Analysis/Analyses/LiveVariables.h"
21 #include "clang/Analysis/Analyses/PseudoConstantAnalysis.h"
22 #include "clang/Analysis/Analyses/CFGReachabilityAnalysis.h"
23 #include "clang/Analysis/AnalysisContext.h"
24 #include "clang/Analysis/CFG.h"
25 #include "clang/Analysis/CFGStmtMap.h"
26 #include "clang/Analysis/Support/BumpVector.h"
27 #include "clang/Analysis/Support/SaveAndRestore.h"
28 #include "llvm/ADT/SmallSet.h"
29 #include "llvm/Support/ErrorHandling.h"
31 using namespace clang;
33 typedef llvm::DenseMap<const void *, ManagedAnalysis *> ManagedAnalysisMap;
35 AnalysisContext::AnalysisContext(const Decl *d,
36 idx::TranslationUnit *tu,
37 const CFG::BuildOptions &buildOptions)
39 cfgBuildOptions(buildOptions),
42 builtCompleteCFG(false),
43 ReferencedBlockVars(0),
46 cfgBuildOptions.forcedBlkExprs = &forcedBlkExprs;
49 AnalysisContext::AnalysisContext(const Decl *d,
50 idx::TranslationUnit *tu)
54 builtCompleteCFG(false),
55 ReferencedBlockVars(0),
58 cfgBuildOptions.forcedBlkExprs = &forcedBlkExprs;
61 AnalysisContextManager::AnalysisContextManager(bool useUnoptimizedCFG,
62 bool addImplicitDtors,
63 bool addInitializers) {
64 cfgBuildOptions.PruneTriviallyFalseEdges = !useUnoptimizedCFG;
65 cfgBuildOptions.AddImplicitDtors = addImplicitDtors;
66 cfgBuildOptions.AddInitializers = addInitializers;
69 void AnalysisContextManager::clear() {
70 for (ContextMap::iterator I = Contexts.begin(), E = Contexts.end(); I!=E; ++I)
75 Stmt *AnalysisContext::getBody() const {
76 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
78 else if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D))
80 else if (const BlockDecl *BD = dyn_cast<BlockDecl>(D))
82 else if (const FunctionTemplateDecl *FunTmpl
83 = dyn_cast_or_null<FunctionTemplateDecl>(D))
84 return FunTmpl->getTemplatedDecl()->getBody();
86 llvm_unreachable("unknown code decl");
89 const ImplicitParamDecl *AnalysisContext::getSelfDecl() const {
90 if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D))
91 return MD->getSelfDecl();
96 void AnalysisContext::registerForcedBlockExpression(const Stmt *stmt) {
98 forcedBlkExprs = new CFG::BuildOptions::ForcedBlkExprs();
99 // Default construct an entry for 'stmt'.
100 if (const Expr *e = dyn_cast<Expr>(stmt))
101 stmt = e->IgnoreParens();
102 (void) (*forcedBlkExprs)[stmt];
106 AnalysisContext::getBlockForRegisteredExpression(const Stmt *stmt) {
107 assert(forcedBlkExprs);
108 if (const Expr *e = dyn_cast<Expr>(stmt))
109 stmt = e->IgnoreParens();
110 CFG::BuildOptions::ForcedBlkExprs::const_iterator itr =
111 forcedBlkExprs->find(stmt);
112 assert(itr != forcedBlkExprs->end());
116 CFG *AnalysisContext::getCFG() {
117 if (!cfgBuildOptions.PruneTriviallyFalseEdges)
118 return getUnoptimizedCFG();
121 cfg.reset(CFG::buildCFG(D, getBody(),
122 &D->getASTContext(), cfgBuildOptions));
123 // Even when the cfg is not successfully built, we don't
124 // want to try building it again.
130 CFG *AnalysisContext::getUnoptimizedCFG() {
131 if (!builtCompleteCFG) {
132 SaveAndRestore<bool> NotPrune(cfgBuildOptions.PruneTriviallyFalseEdges,
134 completeCFG.reset(CFG::buildCFG(D, getBody(), &D->getASTContext(),
136 // Even when the cfg is not successfully built, we don't
137 // want to try building it again.
138 builtCompleteCFG = true;
140 return completeCFG.get();
143 CFGStmtMap *AnalysisContext::getCFGStmtMap() {
145 return cfgStmtMap.get();
147 if (CFG *c = getCFG()) {
148 cfgStmtMap.reset(CFGStmtMap::Build(c, &getParentMap()));
149 return cfgStmtMap.get();
155 CFGReverseBlockReachabilityAnalysis *AnalysisContext::getCFGReachablityAnalysis() {
159 if (CFG *c = getCFG()) {
160 CFA.reset(new CFGReverseBlockReachabilityAnalysis(*c));
167 void AnalysisContext::dumpCFG() {
168 getCFG()->dump(getASTContext().getLangOptions());
171 ParentMap &AnalysisContext::getParentMap() {
173 PM.reset(new ParentMap(getBody()));
177 PseudoConstantAnalysis *AnalysisContext::getPseudoConstantAnalysis() {
179 PCA.reset(new PseudoConstantAnalysis(getBody()));
183 AnalysisContext *AnalysisContextManager::getContext(const Decl *D,
184 idx::TranslationUnit *TU) {
185 AnalysisContext *&AC = Contexts[D];
187 AC = new AnalysisContext(D, TU, cfgBuildOptions);
191 //===----------------------------------------------------------------------===//
192 // FoldingSet profiling.
193 //===----------------------------------------------------------------------===//
195 void LocationContext::ProfileCommon(llvm::FoldingSetNodeID &ID,
197 AnalysisContext *ctx,
198 const LocationContext *parent,
202 ID.AddPointer(parent);
206 void StackFrameContext::Profile(llvm::FoldingSetNodeID &ID) {
207 Profile(ID, getAnalysisContext(), getParent(), CallSite, Block, Index);
210 void ScopeContext::Profile(llvm::FoldingSetNodeID &ID) {
211 Profile(ID, getAnalysisContext(), getParent(), Enter);
214 void BlockInvocationContext::Profile(llvm::FoldingSetNodeID &ID) {
215 Profile(ID, getAnalysisContext(), getParent(), BD);
218 //===----------------------------------------------------------------------===//
219 // LocationContext creation.
220 //===----------------------------------------------------------------------===//
222 template <typename LOC, typename DATA>
224 LocationContextManager::getLocationContext(AnalysisContext *ctx,
225 const LocationContext *parent,
227 llvm::FoldingSetNodeID ID;
228 LOC::Profile(ID, ctx, parent, d);
231 LOC *L = cast_or_null<LOC>(Contexts.FindNodeOrInsertPos(ID, InsertPos));
234 L = new LOC(ctx, parent, d);
235 Contexts.InsertNode(L, InsertPos);
240 const StackFrameContext*
241 LocationContextManager::getStackFrame(AnalysisContext *ctx,
242 const LocationContext *parent,
244 const CFGBlock *blk, unsigned idx) {
245 llvm::FoldingSetNodeID ID;
246 StackFrameContext::Profile(ID, ctx, parent, s, blk, idx);
248 StackFrameContext *L =
249 cast_or_null<StackFrameContext>(Contexts.FindNodeOrInsertPos(ID, InsertPos));
251 L = new StackFrameContext(ctx, parent, s, blk, idx);
252 Contexts.InsertNode(L, InsertPos);
258 LocationContextManager::getScope(AnalysisContext *ctx,
259 const LocationContext *parent,
261 return getLocationContext<ScopeContext, Stmt>(ctx, parent, s);
264 //===----------------------------------------------------------------------===//
265 // LocationContext methods.
266 //===----------------------------------------------------------------------===//
268 const StackFrameContext *LocationContext::getCurrentStackFrame() const {
269 const LocationContext *LC = this;
271 if (const StackFrameContext *SFC = dyn_cast<StackFrameContext>(LC))
273 LC = LC->getParent();
278 const StackFrameContext *
279 LocationContext::getStackFrameForDeclContext(const DeclContext *DC) const {
280 const LocationContext *LC = this;
282 if (const StackFrameContext *SFC = dyn_cast<StackFrameContext>(LC)) {
283 if (cast<DeclContext>(SFC->getDecl()) == DC)
286 LC = LC->getParent();
291 bool LocationContext::isParentOf(const LocationContext *LC) const {
293 const LocationContext *Parent = LC->getParent();
303 //===----------------------------------------------------------------------===//
304 // Lazily generated map to query the external variables referenced by a Block.
305 //===----------------------------------------------------------------------===//
308 class FindBlockDeclRefExprsVals : public StmtVisitor<FindBlockDeclRefExprsVals>{
309 BumpVector<const VarDecl*> &BEVals;
310 BumpVectorContext &BC;
311 llvm::DenseMap<const VarDecl*, unsigned> Visited;
312 llvm::SmallSet<const DeclContext*, 4> IgnoredContexts;
314 FindBlockDeclRefExprsVals(BumpVector<const VarDecl*> &bevals,
315 BumpVectorContext &bc)
316 : BEVals(bevals), BC(bc) {}
318 bool IsTrackedDecl(const VarDecl *VD) {
319 const DeclContext *DC = VD->getDeclContext();
320 return IgnoredContexts.count(DC) == 0;
323 void VisitStmt(Stmt *S) {
324 for (Stmt::child_range I = S->children(); I; ++I)
325 if (Stmt *child = *I)
329 void VisitDeclRefExpr(const DeclRefExpr *DR) {
330 // Non-local variables are also directly modified.
331 if (const VarDecl *VD = dyn_cast<VarDecl>(DR->getDecl()))
332 if (!VD->hasLocalStorage()) {
333 unsigned &flag = Visited[VD];
336 BEVals.push_back(VD, BC);
341 void VisitBlockDeclRefExpr(BlockDeclRefExpr *DR) {
342 if (const VarDecl *VD = dyn_cast<VarDecl>(DR->getDecl())) {
343 unsigned &flag = Visited[VD];
346 if (IsTrackedDecl(VD))
347 BEVals.push_back(VD, BC);
352 void VisitBlockExpr(BlockExpr *BR) {
353 // Blocks containing blocks can transitively capture more variables.
354 IgnoredContexts.insert(BR->getBlockDecl());
355 Visit(BR->getBlockDecl()->getBody());
358 } // end anonymous namespace
360 typedef BumpVector<const VarDecl*> DeclVec;
362 static DeclVec* LazyInitializeReferencedDecls(const BlockDecl *BD,
364 llvm::BumpPtrAllocator &A) {
366 return (DeclVec*) Vec;
368 BumpVectorContext BC(A);
369 DeclVec *BV = (DeclVec*) A.Allocate<DeclVec>();
370 new (BV) DeclVec(BC, 10);
372 // Find the referenced variables.
373 FindBlockDeclRefExprsVals F(*BV, BC);
374 F.Visit(BD->getBody());
380 std::pair<AnalysisContext::referenced_decls_iterator,
381 AnalysisContext::referenced_decls_iterator>
382 AnalysisContext::getReferencedBlockVars(const BlockDecl *BD) {
383 if (!ReferencedBlockVars)
384 ReferencedBlockVars = new llvm::DenseMap<const BlockDecl*,void*>();
386 DeclVec *V = LazyInitializeReferencedDecls(BD, (*ReferencedBlockVars)[BD], A);
387 return std::make_pair(V->begin(), V->end());
390 ManagedAnalysis *&AnalysisContext::getAnalysisImpl(const void *tag) {
391 if (!ManagedAnalyses)
392 ManagedAnalyses = new ManagedAnalysisMap();
393 ManagedAnalysisMap *M = (ManagedAnalysisMap*) ManagedAnalyses;
397 //===----------------------------------------------------------------------===//
399 //===----------------------------------------------------------------------===//
401 ManagedAnalysis::~ManagedAnalysis() {}
403 AnalysisContext::~AnalysisContext() {
404 delete forcedBlkExprs;
405 delete ReferencedBlockVars;
406 // Release the managed analyses.
407 if (ManagedAnalyses) {
408 ManagedAnalysisMap *M = (ManagedAnalysisMap*) ManagedAnalyses;
409 for (ManagedAnalysisMap::iterator I = M->begin(), E = M->end(); I!=E; ++I)
415 AnalysisContextManager::~AnalysisContextManager() {
416 for (ContextMap::iterator I = Contexts.begin(), E = Contexts.end(); I!=E; ++I)
420 LocationContext::~LocationContext() {}
422 LocationContextManager::~LocationContextManager() {
426 void LocationContextManager::clear() {
427 for (llvm::FoldingSet<LocationContext>::iterator I = Contexts.begin(),
428 E = Contexts.end(); I != E; ) {
429 LocationContext *LC = &*I;