diff options
| -rw-r--r-- | lib/Analysis/CheckDeadStores.cpp | 42 | ||||
| -rw-r--r-- | lib/Analysis/LiveVariables.cpp | 18 |
2 files changed, 38 insertions, 22 deletions
diff --git a/lib/Analysis/CheckDeadStores.cpp b/lib/Analysis/CheckDeadStores.cpp index f75a96471a..69433d6396 100644 --- a/lib/Analysis/CheckDeadStores.cpp +++ b/lib/Analysis/CheckDeadStores.cpp @@ -17,9 +17,11 @@ #include "clang/Analysis/Visitors/CFGRecStmtVisitor.h" #include "clang/Analysis/PathSensitive/BugReporter.h" #include "clang/Analysis/PathSensitive/GRExprEngine.h" +#include "clang/Analysis/Visitors/CFGRecStmtDeclVisitor.h" #include "clang/Basic/Diagnostic.h" #include "clang/AST/ASTContext.h" #include "clang/AST/ParentMap.h" +#include "llvm/ADT/SmallPtrSet.h" #include "llvm/Support/Compiler.h" using namespace clang; @@ -30,16 +32,20 @@ class VISIBILITY_HIDDEN DeadStoreObs : public LiveVariables::ObserverTy { ASTContext &Ctx; BugReporter& BR; ParentMap& Parents; + llvm::SmallPtrSet<VarDecl*, 20> Escaped; enum DeadStoreKind { Standard, Enclosing, DeadIncrement, DeadInit }; public: - DeadStoreObs(ASTContext &ctx, BugReporter& br, ParentMap& parents) - : Ctx(ctx), BR(br), Parents(parents) {} + DeadStoreObs(ASTContext &ctx, BugReporter& br, ParentMap& parents, + llvm::SmallPtrSet<VarDecl*, 20> &escaped) + : Ctx(ctx), BR(br), Parents(parents), Escaped(escaped) {} virtual ~DeadStoreObs() {} void Report(VarDecl* V, DeadStoreKind dsk, SourceLocation L, SourceRange R) { + if (Escaped.count(V)) + return; std::string name = V->getNameAsString(); @@ -219,7 +225,35 @@ public: // Driver function to invoke the Dead-Stores checker on a CFG. //===----------------------------------------------------------------------===// -void clang::CheckDeadStores(LiveVariables& L, BugReporter& BR) { - DeadStoreObs A(BR.getContext(), BR, BR.getParentMap()); +namespace { +class VISIBILITY_HIDDEN FindEscaped : public CFGRecStmtDeclVisitor<FindEscaped>{ + CFG *cfg; +public: + FindEscaped(CFG *c) : cfg(c) {} + + CFG& getCFG() { return *cfg; } + + llvm::SmallPtrSet<VarDecl*, 20> Escaped; + + void VisitUnaryOperator(UnaryOperator* U) { + // Check for '&'. Any VarDecl whose value has its address-taken we + // treat as escaped. + Expr* E = U->getSubExpr()->IgnoreParenCasts(); + if (U->getOpcode() == UnaryOperator::AddrOf) + if (DeclRefExpr* DR = dyn_cast<DeclRefExpr>(E)) + if (VarDecl* VD = dyn_cast<VarDecl>(DR->getDecl())) { + Escaped.insert(VD); + return; + } + Visit(E); + } +}; +} // end anonymous namespace + + +void clang::CheckDeadStores(LiveVariables& L, BugReporter& BR) { + FindEscaped FS(BR.getCFG()); + FS.getCFG().VisitBlockStmts(FS); + DeadStoreObs A(BR.getContext(), BR, BR.getParentMap(), FS.Escaped); L.runOnAllBlocks(*BR.getCFG(), &A); } diff --git a/lib/Analysis/LiveVariables.cpp b/lib/Analysis/LiveVariables.cpp index b8b0aaca18..b0eb37b065 100644 --- a/lib/Analysis/LiveVariables.cpp +++ b/lib/Analysis/LiveVariables.cpp @@ -74,28 +74,10 @@ public: AlwaysLive.push_back(VD); } - void VisitUnaryOperator(UnaryOperator* U) { - // Check for '&'. Any VarDecl whose value has its address-taken we - // treat as always being live (flow-insensitive). - - Expr* E = U->getSubExpr()->IgnoreParenCasts(); - - if (U->getOpcode() == UnaryOperator::AddrOf) - if (DeclRefExpr* DR = dyn_cast<DeclRefExpr>(E)) - if (VarDecl* VD = dyn_cast<VarDecl>(DR->getDecl())) { - AD.Register(VD); - AlwaysLive.push_back(VD); - return; - } - - Visit(E); - } - CFG& getCFG() { return AD.getCFG(); } }; } // end anonymous namespace - LiveVariables::LiveVariables(ASTContext& Ctx, CFG& cfg) { // Register all referenced VarDecls. getAnalysisData().setCFG(cfg); |