Fix <rdar://problem/6611677>: Add basic transfer function support in the static

analyzer for array subscript expressions involving bases that are vectors. This
solution is probably a hack: it gets the lvalue of the vector instead of an
rvalue like all other types. This should be reviewed (big FIXME in
GRExprEngine).

llvm-svn: 65366

2 files changed, 18 insertions, 3 deletions

diff --git a/clang/lib/Analysis/GRExprEngine.cpp b/clang/lib/Analysis/GRExprEngine.cpp
index 60bef6eb718..d34e8a3ed3a 100644
--- a/clang/lib/Analysis/GRExprEngine.cpp
+++ b/clang/lib/Analysis/GRExprEngine.cpp
@@ -850,7 +850,16 @@ void GRExprEngine::VisitArraySubscriptExpr(ArraySubscriptExpr* A, NodeTy* Pred,
   Expr* Base = A->getBase()->IgnoreParens();
   Expr* Idx  = A->getIdx()->IgnoreParens();
   NodeSet Tmp;
-  Visit(Base, Pred, Tmp);   // Get Base's rvalue, which should be an LocVal.
+  
+  if (Base->getType()->isVectorType()) {
+    // For vector types get its lvalue.
+    // FIXME: This may not be correct.  Is the rvalue of a vector its location?
+    //  In fact, I think this is just a hack.  We need to get the right
+    // semantics.
+    VisitLValue(Base, Pred, Tmp);
+  }
+  else  
+    Visit(Base, Pred, Tmp);   // Get Base's rvalue, which should be an LocVal.
   
   for (NodeSet::iterator I1=Tmp.begin(), E1=Tmp.end(); I1!=E1; ++I1) {    
     NodeSet Tmp2;
diff --git a/clang/lib/Analysis/RegionStore.cpp b/clang/lib/Analysis/RegionStore.cpp
index e2a1d361822..c61094c20cd 100644
--- a/clang/lib/Analysis/RegionStore.cpp
+++ b/clang/lib/Analysis/RegionStore.cpp
@@ -591,9 +591,14 @@ SVal RegionStoreManager::Retrieve(const GRState* St, Loc L, QualType T) {
   //
   // Such funny addressing will occur due to layering of regions.
 
-  if (const TypedRegion* TR = dyn_cast<TypedRegion>(R))
-    if (TR->getRValueType(getContext())->isStructureType())
+  if (const TypedRegion* TR = dyn_cast<TypedRegion>(R)) {
+    QualType T =TR->getRValueType(getContext());
+    if (T->isStructureType())
       return RetrieveStruct(St, TR);
+    // FIXME: handle Vector types.
+    if (T->isVectorType())
+      return UnknownVal();
+  }
   
   RegionBindingsTy B = GetRegionBindings(St->getStore());
   RegionBindingsTy::data_type* V = B.lookup(R);
@@ -636,6 +641,7 @@ SVal RegionStoreManager::Retrieve(const GRState* St, Loc L, QualType T) {
       return loc::MemRegionVal(getSelfRegion(0));
   }
   
+
   if (MRMgr.onStack(R) || MRMgr.onHeap(R)) {
     // All stack variables are considered to have undefined values
     // upon creation.  All heap allocated blocks are considered to