Add logic for invalidating array region to CFRefCount.cpp. When invalidating

array region, set its default value to conjured symbol. When retrieving its
element, create new region value symbol for the element.

Also fix some 80 columns violations.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@71548 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/Analysis/PathSensitive/MemRegion.h

@@ -217,6 +217,7 @@ public:
   }
 
   bool isDeclared() const { return codekind == Declared; }
+  bool isSymbolic() const { return codekind == Symbolic; }
 
   const FunctionDecl* getDecl() const {
     assert(codekind == Declared);

include/clang/Analysis/PathSensitive/SVals.h

@@ -90,6 +90,9 @@ public:
   
   bool isZeroConstant() const;
 
+  /// hasConjuredSymbol - If this SVal wraps a conjured symbol, return true;
+  bool hasConjuredSymbol() const;
+
   /// getAsFunctionDecl - If this SVal is a MemRegionVal and wraps a
   /// CodeTextRegion wrapping a FunctionDecl, return that FunctionDecl. 
   /// Otherwise return 0.

include/clang/Analysis/PathSensitive/Store.h

@@ -161,6 +161,11 @@ public:
     return St;
   }
 
+  virtual const GRState* setDefaultValue(const GRState* St,
+                                         const MemRegion* R, SVal V) {
+    return St;
+  }
+
   virtual void print(Store store, std::ostream& Out,
                      const char* nl, const char *sep) = 0;
       

lib/Analysis/CFRefCount.cpp

@@ -1721,7 +1721,7 @@ private:
 
   void ProcessNonLeakError(ExplodedNodeSet<GRState>& Dst,
                            GRStmtNodeBuilder<GRState>& Builder,
-                           Expr* NodeExpr, Expr* ErrorExpr,                        
+                           Expr* NodeExpr, Expr* ErrorExpr,
                            ExplodedNode<GRState>* Pred,
                            const GRState* St,
                            RefVal::Kind hasErr, SymbolRef Sym);
@@ -1767,7 +1767,7 @@ public:
                    Expr* Ex,
                    Expr* Receiver,
                    const RetainSummary& Summ,
-                   ExprIterator arg_beg, ExprIterator arg_end,                             
+                   ExprIterator arg_beg, ExprIterator arg_end,
                    ExplodedNode<GRState>* Pred);
     
   virtual void EvalCall(ExplodedNodeSet<GRState>& Dst,
@@ -1995,7 +1995,7 @@ namespace {
 
     CFRefReport(CFRefBug& D, const CFRefCount &tf,
                 ExplodedNode<GRState> *n, SymbolRef sym, const char* endText)
-      : RangedBugReport(D, D.getDescription(), endText, n), Sym(sym), TF(tf) {}    
+      : RangedBugReport(D, D.getDescription(), endText, n), Sym(sym), TF(tf) {}
     
     virtual ~CFRefReport() {}
     
@@ -2302,7 +2302,7 @@ PathDiagnosticPiece* CFRefReport::VisitNode(const ExplodedNode<GRState>* N,
             if (PrevV.getAutoreleaseCount() == CurrV.getAutoreleaseCount())
               return 0;
             
-            assert(PrevV.getAutoreleaseCount() < CurrV.getAutoreleaseCount());            
+            assert(PrevV.getAutoreleaseCount() < CurrV.getAutoreleaseCount());
             os << "Object sent -autorelease message";
             break;
           }
@@ -2623,8 +2623,10 @@ void CFRefCount::EvalSummary(ExplodedNodeSet<GRState>& Dst,
                              ExplodedNode<GRState>* Pred) {
   
   // Get the state.
-  GRStateRef state(Builder.GetState(Pred), Eng.getStateManager());
-  ASTContext& Ctx = Eng.getStateManager().getContext();
+  GRStateManager& StateMgr = Eng.getStateManager();
+  GRStateRef state(Builder.GetState(Pred), StateMgr);
+  ASTContext& Ctx = StateMgr.getContext();
+  ValueManager &ValMgr = Eng.getValueManager();
 
   // Evaluate the effect of the arguments.
   RefVal::Kind hasErr = (RefVal::Kind) 0;
@@ -2680,7 +2682,7 @@ void CFRefCount::EvalSummary(ExplodedNodeSet<GRState>& Dst,
             // with an interface to StoreManager so that this logic can be
             // approriately delegated to the respective StoreManagers while
             // still allowing us to do checker-specific logic (e.g.,
-            // invalidating reference counts), probably via callbacks.            
+            // invalidating reference counts), probably via callbacks.
             if (ER->getElementType()->isIntegralType()) {
               const MemRegion *superReg = ER->getSuperRegion();
               if (isa<VarRegion>(superReg) || isa<FieldRegion>(superReg) ||
@@ -2730,15 +2732,21 @@ void CFRefCount::EvalSummary(ExplodedNodeSet<GRState>& Dst,
                 QualType FT = FD->getType();
                 
                 if (Loc::IsLocType(FT) || 
-                    (FT->isIntegerType() && FT->isScalarType())) {                  
+                    (FT->isIntegerType() && FT->isScalarType())) {
                   const FieldRegion* FR = MRMgr.getFieldRegion(FD, R);
-                  ValueManager &ValMgr = Eng.getValueManager();
+
                   SVal V = ValMgr.getConjuredSymbolVal(*I, FT, Count);
                   state = state.BindLoc(Loc::MakeVal(FR), V);
                 }                
               }
-            }
-            else {
+            } else if (const ArrayType *AT = Ctx.getAsArrayType(T)) {
+              // Set the default value of the array to conjured symbol.
+              StoreManager& StoreMgr = Eng.getStateManager().getStoreManager();
+              SVal V = ValMgr.getConjuredSymbolVal(*I, AT->getElementType(),
+                                                   Count);
+              state = GRStateRef(StoreMgr.setDefaultValue(state, R, V), 
+                                 StateMgr);
+            } else {
               // Just blast away other values.
               state = state.BindLoc(*MR, UnknownVal());
             }

lib/Analysis/RegionStore.cpp

@@ -276,7 +276,7 @@ public:
   void iterBindings(Store store, BindingsHandler& f) {
     // FIXME: Implement.
   }
-
+  const GRState* setDefaultValue(const GRState* St, const MemRegion* R, SVal V);
 private:
   const GRState* BindArray(const GRState* St, const TypedRegion* R, SVal V);
 
@@ -759,8 +759,13 @@ SVal RegionStoreManager::Retrieve(const GRState* St, Loc L, QualType T) {
     const MemRegion* SuperR = cast<SubRegion>(R)->getSuperRegion();
     GRStateTrait<RegionDefaultValue>::lookup_type D = 
       state.get<RegionDefaultValue>(SuperR);
-    if (D)
-      return *D;
+    if (D) {
+      // If the default value is symbolic, we need to create a new symbol.
+      if (D->hasConjuredSymbol())
+        return ValMgr.getRegionValueSymbolVal(R);
+      else
+        return *D;
+    }
   }
   
   if (const ObjCIvarRegion *IVR = dyn_cast<ObjCIvarRegion>(R)) {
@@ -1274,3 +1279,9 @@ const GRState* RegionStoreManager::setCastType(const GRState* St,
   GRStateRef state(St, StateMgr);
   return state.set<RegionCasts>(R, T);
 }
+
+const GRState* RegionStoreManager::setDefaultValue(const GRState* St,
+                                                   const MemRegion* R, SVal V) {
+  GRStateRef state(St, StateMgr);
+  return state.set<RegionDefaultValue>(R, V);
+}

lib/Analysis/SVals.cpp

@@ -30,6 +30,31 @@ using llvm::APSInt;
 // Utility methods.
 //===----------------------------------------------------------------------===//
 
+bool SVal::hasConjuredSymbol() const {
+  if (const nonloc::SymbolVal* SV = dyn_cast<nonloc::SymbolVal>(this)) {
+    SymbolRef sym = SV->getSymbol();
+    if (isa<SymbolConjured>(sym))
+      return true;
+  }
+
+  if (const loc::MemRegionVal *RV = dyn_cast<loc::MemRegionVal>(this)) {
+    const MemRegion *R = RV->getRegion();
+    if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(R)) {
+      SymbolRef sym = SR->getSymbol();
+      if (isa<SymbolConjured>(sym))
+        return true;
+    } else if (const CodeTextRegion *CTR = dyn_cast<CodeTextRegion>(R)) {
+      if (CTR->isSymbolic()) {
+        SymbolRef sym = CTR->getSymbol();
+        if (isa<SymbolConjured>(sym))
+          return true;
+      }
+    }
+  }
+
+  return false;
+}
+
 const FunctionDecl* SVal::getAsFunctionDecl() const {
   if (const loc::MemRegionVal* X = dyn_cast<loc::MemRegionVal>(this)) {
     const MemRegion* R = X->getRegion();

test/Analysis/array-struct.c

@@ -132,3 +132,13 @@ static struct s3 opt;
 void f14() {
   struct s3 my_opt = opt;
 }
+
+void bar(int*);
+
+// Test if the array is correctly invalidated.
+void f15() {
+  int a[10];
+  bar(a);
+  if (a[1]) // no-warning
+    1;
+}