[cfe-commits] r91952 - in /cfe/trunk: include/clang/Analysis/PathSensitive/GRExprEngine.h lib/Analysis/GRExprEngine.cpp test/Analysis/misc-ps-region-store.cpp

[Ted Kremenek]

Author: kremenek
Date: Tue Dec 22 18:26:16 2009
New Revision: 91952

URL: http://llvm.org/viewvc/llvm-project?rev=91952&view=rev
Log:
Add basic support for analyzing CastExprs as lvalues.

Modified:
    cfe/trunk/include/clang/Analysis/PathSensitive/GRExprEngine.h
    cfe/trunk/lib/Analysis/GRExprEngine.cpp
    cfe/trunk/test/Analysis/misc-ps-region-store.cpp

Modified: cfe/trunk/include/clang/Analysis/PathSensitive/GRExprEngine.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Analysis/PathSensitive/GRExprEngine.h?rev=91952&r1=91951&r2=91952&view=diff

==============================================================================
--- cfe/trunk/include/clang/Analysis/PathSensitive/GRExprEngine.h (original)
+++ cfe/trunk/include/clang/Analysis/PathSensitive/GRExprEngine.h Tue Dec 22 18:26:16 2009
@@ -269,7 +269,7 @@
 
   /// VisitCast - Transfer function logic for all casts (implicit and explicit).
   void VisitCast(Expr* CastE, Expr* Ex, ExplodedNode* Pred,
-                 ExplodedNodeSet& Dst);
+                 ExplodedNodeSet& Dst, bool asLValue);
 
   /// VisitCompoundLiteralExpr - Transfer function logic for compound literals.
   void VisitCompoundLiteralExpr(CompoundLiteralExpr* CL, ExplodedNode* Pred,

Modified: cfe/trunk/lib/Analysis/GRExprEngine.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Analysis/GRExprEngine.cpp?rev=91952&r1=91951&r2=91952&view=diff

==============================================================================
--- cfe/trunk/lib/Analysis/GRExprEngine.cpp (original)
+++ cfe/trunk/lib/Analysis/GRExprEngine.cpp Tue Dec 22 18:26:16 2009
@@ -658,7 +658,7 @@
     case Stmt::ImplicitCastExprClass:
     case Stmt::CStyleCastExprClass: {
       CastExpr* C = cast<CastExpr>(S);
-      VisitCast(C, C->getSubExpr(), Pred, Dst);
+      VisitCast(C, C->getSubExpr(), Pred, Dst, false);
       break;
     }
 
@@ -753,6 +753,13 @@
   }
 
   switch (Ex->getStmtClass()) {
+    // C++ stuff we don't support yet.
+    case Stmt::CXXMemberCallExprClass: {
+      SaveAndRestore<bool> OldSink(Builder->BuildSinks);
+      Builder->BuildSinks = true;
+      MakeNode(Dst, Ex, Pred, GetState(Pred));
+      break;
+    }
 
     case Stmt::ArraySubscriptExprClass:
       VisitArraySubscriptExpr(cast<ArraySubscriptExpr>(Ex), Pred, Dst, true);
@@ -783,6 +790,14 @@
       VisitDeclRefExpr(cast<DeclRefExpr>(Ex), Pred, Dst, true);
       return;
       
+    case Stmt::ImplicitCastExprClass:
+    case Stmt::CStyleCastExprClass: {
+      CastExpr *C = cast<CastExpr>(Ex);
+      QualType T = Ex->getType();
+      VisitCast(C, C->getSubExpr(), Pred, Dst, true);
+      break;
+    }
+      
     case Stmt::MemberExprClass:
       VisitMemberExpr(cast<MemberExpr>(Ex), Pred, Dst, true);
       return;
@@ -2080,7 +2095,7 @@
 //===----------------------------------------------------------------------===//
 
 void GRExprEngine::VisitCast(Expr* CastE, Expr* Ex, ExplodedNode* Pred, 
-                             ExplodedNodeSet& Dst){
+                             ExplodedNodeSet& Dst, bool asLValue){
   ExplodedNodeSet S1;
   QualType T = CastE->getType();
   QualType ExTy = Ex->getType();
@@ -2088,7 +2103,8 @@
   if (const ExplicitCastExpr *ExCast=dyn_cast_or_null<ExplicitCastExpr>(CastE))
     T = ExCast->getTypeAsWritten();
 
-  if (ExTy->isArrayType() || ExTy->isFunctionType() || T->isReferenceType())
+  if (ExTy->isArrayType() || ExTy->isFunctionType() || T->isReferenceType() ||
+      asLValue)
     VisitLValue(Ex, Pred, S1);
   else
     Visit(Ex, Pred, S1);
@@ -2098,10 +2114,18 @@
 
   // Check for casting to "void".
   if (T->isVoidType()) {
+    assert(!asLValue);
     for (ExplodedNodeSet::iterator I = S2.begin(), E = S2.end(); I != E; ++I)
       Dst.Add(*I);
     return;
   }
+  
+  // If we are evaluating the cast in an lvalue context, we implicitly want
+  // the cast to evaluate to a location.
+  if (asLValue) {
+    ASTContext &Ctx = getContext();
+    T = Ctx.getPointerType(Ctx.getCanonicalType(T));
+  }
 
   for (ExplodedNodeSet::iterator I = S2.begin(), E = S2.end(); I != E; ++I) {
     ExplodedNode* N = *I;

Modified: cfe/trunk/test/Analysis/misc-ps-region-store.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Analysis/misc-ps-region-store.cpp?rev=91952&r1=91951&r2=91952&view=diff

==============================================================================
--- cfe/trunk/test/Analysis/misc-ps-region-store.cpp (original)
+++ cfe/trunk/test/Analysis/misc-ps-region-store.cpp Tue Dec 22 18:26:16 2009
@@ -12,3 +12,14 @@
   return test1_aux();
 }
 
+// Test passing a value as a reference.  The 'const' in test2_aux() adds
+// an ImplicitCastExpr, which is evaluated as an lvalue.
+int test2_aux(const int &n);
+int test2(int n) {
+  return test2_aux(n);
+}
+
+int test2_b_aux(const short &n);
+int test2_b(int n) {
+  return test2_b_aux(n);
+}